libmdbx extracted back to the separate module, otherwise dbx_mdbx is marked as new on each rebuild

19 files changed, 1 insertions, 65415 deletions

diff --git a/plugins/Dbx_mdbx/src/libmdbx/CMakeLists.txt b/plugins/Dbx_mdbx/src/libmdbx/CMakeLists.txt
deleted file mode 100644
index 46afa66fca..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/CMakeLists.txt
+++ /dev/null
@@ -1,866 +0,0 @@
-##
-##  Copyright 2020-2021 Leonid Yuriev <leo@yuriev.ru>
-##  and other libmdbx authors: please see AUTHORS file.
-##  All rights reserved.
-##
-##  Redistribution and use in source and binary forms, with or without
-##  modification, are permitted only as authorized by the OpenLDAP
-##  Public License.
-##
-##  A copy of this license is available in the file LICENSE in the
-##  top-level directory of the distribution or, alternatively, at
-##  <http://www.OpenLDAP.org/license.html>.
-##
-
-##
-##  libmdbx = { Revised and extended descendant of Symas LMDB. }
-##  Please see README.md at https://github.com/erthink/libmdbx
-##
-##  Libmdbx is superior to LMDB in terms of features and reliability,
-##  not inferior in performance. libmdbx works on Linux, FreeBSD, MacOS X
-##  and other systems compliant with POSIX.1-2008, but also support Windows
-##  as a complementary platform.
-##
-##  The next version is under active non-public development and will be
-##  released as MithrilDB and libmithrildb for libraries & packages.
-##  Admittedly mythical Mithril is resembling silver but being stronger and
-##  lighter than steel. Therefore MithrilDB is rightly relevant name.
-##
-##  MithrilDB will be radically different from libmdbx by the new database
-##  format and API based on C++17, as well as the Apache 2.0 License.
-##  The goal of this revolution is to provide a clearer and robust API,
-##  add more features and new valuable properties of database.
-##
-##  The Future will (be) Positive. Всё будет хорошо.
-##
-
-cmake_minimum_required(VERSION 3.8.2)
-
-cmake_policy(PUSH)
-cmake_policy(VERSION 3.8.2)
-if(NOT CMAKE_VERSION VERSION_LESS 3.15)
-  cmake_policy(SET CMP0091 NEW)
-endif()
-if(NOT CMAKE_VERSION VERSION_LESS 3.13)
-  cmake_policy(SET CMP0077 NEW)
-endif()
-if(NOT CMAKE_VERSION VERSION_LESS 3.12)
-  cmake_policy(SET CMP0075 NEW)
-endif()
-if(NOT CMAKE_VERSION VERSION_LESS 3.9)
-  cmake_policy(SET CMP0069 NEW)
-  include(CheckIPOSupported)
-  check_ipo_supported(RESULT CMAKE_INTERPROCEDURAL_OPTIMIZATION_AVAILABLE)
-else()
-  set(CMAKE_INTERPROCEDURAL_OPTIMIZATION_AVAILABLE FALSE)
-endif()
-
-if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/.git" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/test/CMakeLists.txt" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/core.c" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/alloy.c" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/config.h.in" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/version.c.in" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/man1" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/mdbx_chk.c" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/src/mdbx.c++")
-  set(MDBX_AMALGAMATED_SOURCE FALSE)
-  find_program(GIT git)
-  if(NOT GIT)
-    message(SEND_ERROR "Git command-line tool not found")
-  endif()
-  set(MDBX_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/src")
-elseif(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/VERSION" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/mdbx.c" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/mdbx.c++" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/config.h.in" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/man1" AND
-    EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/mdbx_chk.c")
-  set(MDBX_AMALGAMATED_SOURCE TRUE)
-  set(MDBX_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
-else()
-  message(FATAL_ERROR "Please use libmdbx as a git-submodule or the amalgamated source code")
-endif()
-
-if(DEFINED PROJECT_NAME)
-  set(SUBPROJECT ON)
-  set(NOT_SUBPROJECT OFF)
-  if(NOT MDBX_AMALGAMATED_SOURCE AND NOT DEFINED BUILD_TESTING)
-    set(BUILD_TESTING OFF)
-  endif()
-  enable_language(C)
-else()
-  set(SUBPROJECT OFF)
-  set(NOT_SUBPROJECT ON)
-  project(libmdbx C)
-  if(NOT MDBX_AMALGAMATED_SOURCE AND NOT DEFINED BUILD_TESTING)
-    set(BUILD_TESTING ON)
-  endif()
-endif()
-
-if(MDBX_AMALGAMATED_SOURCE AND DEFINED MDBX_ENABLE_TESTS AND MDBX_ENABLE_TESTS)
-  message(WARNING "MDBX_ENABLE_TESTS=${MDBX_ENABLE_TESTS}: But amalgamated source code don't includes tests.")
-  set(MDBX_ENABLE_TESTS OFF)
-endif()
-
-# Try to find a C++ compiler unless sure that this is unnecessary.
-if (NOT CMAKE_CXX_COMPILER_LOADED)
-  include(CheckLanguage)
-  if(NOT DEFINED MDBX_BUILD_CXX OR MDBX_BUILD_CXX
-      OR (NOT MDBX_AMALGAMATED_SOURCE AND (NOT DEFINED MDBX_ENABLE_TESTS OR MDBX_ENABLE_TESTS)))
-    check_language(CXX)
-    if(CMAKE_CXX_COMPILER)
-      enable_language(CXX)
-    endif()
-  endif()
-else()
-  enable_language(CXX)
-endif()
-
-if(NOT CMAKE_BUILD_TYPE)
-  set(CMAKE_BUILD_TYPE MinSizeRel CACHE STRING
-    "Choose the type of build, options are: Debug Release RelWithDebInfo MinSizeRel."
-    FORCE)
-endif()
-
-if(NOT_SUBPROJECT AND (CMAKE_CROSSCOMPILING OR IOS))
-  set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
-endif()
-
-if(NOT "$ENV{TEAMCITY_PROCESS_FLOW_ID}" STREQUAL "")
-  set(CI TEAMCITY)
-  message(STATUS "TeamCity CI")
-elseif(NOT "$ENV{TRAVIS}" STREQUAL "")
-  set(CI TRAVIS)
-  message(STATUS "Travis CI")
-elseif(NOT "$ENV{CIRCLECI}" STREQUAL "")
-  set(CI CIRCLE)
-  message(STATUS "Circle CI")
-elseif(NOT "$ENV{APPVEYOR}" STREQUAL "")
-  set(CI APPVEYOR)
-  message(STATUS "AppVeyor CI")
-elseif(NOT "$ENV{CI}" STREQUAL "")
-  set(CI "$ENV{CI}")
-  message(STATUS "Other CI (${CI})")
-else()
-  message(STATUS "Assume No any CI environment")
-  unset(CI)
-endif()
-
-# output all mdbx-related targets in single directory
-if(NOT DEFINED MDBX_OUTPUT_DIR)
-  set(MDBX_OUTPUT_DIR ${CMAKE_CURRENT_BINARY_DIR})
-endif()
-set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${MDBX_OUTPUT_DIR})
-set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${MDBX_OUTPUT_DIR})
-set(CMAKE_PDB_OUTPUT_DIRECTORY ${MDBX_OUTPUT_DIR})
-set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${MDBX_OUTPUT_DIR})
-
-include(CheckFunctionExists)
-include(FindPackageMessage)
-include(GNUInstallDirs)
-
-if(CMAKE_C_COMPILER_ID STREQUAL "MSVC" AND MSVC_VERSION LESS 1900)
-  message(SEND_ERROR "MSVC compiler ${MSVC_VERSION} is too old for building MDBX."
-    " At least 'Microsoft Visual Studio 2015' is required.")
-endif()
-
-# Set default build type to Release. This is to ease a User's life.
-if(NOT CMAKE_BUILD_TYPE)
-  set(CMAKE_BUILD_TYPE Release CACHE STRING
-    "Choose the type of build, options are: Debug Release RelWithDebInfo MinSizeRel."
-    FORCE)
-endif()
-string(TOUPPER ${CMAKE_BUILD_TYPE} CMAKE_BUILD_TYPE_UPPERCASE)
-
-set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
-set(THREADS_PREFER_PTHREAD_FLAG TRUE)
-find_package(Threads REQUIRED)
-
-include(cmake/utils.cmake)
-include(cmake/compiler.cmake)
-include(cmake/profile.cmake)
-
-# Workaround for `-pthread` toolchain/cmake bug
-if(NOT APPLE AND NOT MSVC
-    AND CMAKE_USE_PTHREADS_INIT AND NOT CMAKE_THREAD_LIBS_INIT
-    AND (CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_CLANG))
-  check_compiler_flag("-pthread" CC_HAS_PTHREAD)
-  if(CC_HAS_PTHREAD AND NOT CMAKE_EXE_LINKER_FLAGS MATCHES "-pthread")
-    message(STATUS "Force add -pthread for linker flags to avoid troubles")
-    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -pthread")
-    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -pthread")
-    set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -pthread")
-  endif()
-endif()
-
-CHECK_FUNCTION_EXISTS(pow NOT_NEED_LIBM)
-if(NOT_NEED_LIBM)
-  set(LIB_MATH "")
-else()
-  set(CMAKE_REQUIRED_LIBRARIES m)
-  CHECK_FUNCTION_EXISTS(pow HAVE_LIBM)
-  if(HAVE_LIBM)
-    set(LIB_MATH m)
-  else()
-    message(FATAL_ERROR "No libm found for math support")
-  endif()
-endif()
-
-if(SUBPROJECT)
-  if(NOT DEFINED BUILD_SHARED_LIBS)
-    option(BUILD_SHARED_LIBS "Build shared libraries (DLLs)" OFF)
-  endif()
-  if(NOT DEFINED CMAKE_POSITION_INDEPENDENT_CODE)
-    option(CMAKE_POSITION_INDEPENDENT_CODE "Generate position independent (PIC)" ON)
-  endif()
-else()
-  option(BUILD_SHARED_LIBS "Build shared libraries (DLLs)" ON)
-  option(CMAKE_POSITION_INDEPENDENT_CODE "Generate position independent (PIC)" ON)
-  if (CC_HAS_ARCH_NATIVE)
-    option(BUILD_FOR_NATIVE_CPU "Generate code for the compiling machine CPU" OFF)
-  endif()
-
-  if(CMAKE_CONFIGURATION_TYPES OR NOT CMAKE_BUILD_TYPE_UPPERCASE STREQUAL "DEBUG")
-    set(INTERPROCEDURAL_OPTIMIZATION_DEFAULT ON)
-  else()
-    set(INTERPROCEDURAL_OPTIMIZATION_DEFAULT OFF)
-  endif()
-
-  if(CMAKE_INTERPROCEDURAL_OPTIMIZATION_AVAILABLE
-      OR GCC_LTO_AVAILABLE OR MSVC_LTO_AVAILABLE OR CLANG_LTO_AVAILABLE)
-    option(INTERPROCEDURAL_OPTIMIZATION "Enable interprocedural/LTO optimization" ${INTERPROCEDURAL_OPTIMIZATION_DEFAULT})
-  endif()
-
-  if(INTERPROCEDURAL_OPTIMIZATION)
-    if(GCC_LTO_AVAILABLE)
-      set(LTO_ENABLED TRUE)
-      set(CMAKE_AR ${CMAKE_GCC_AR} CACHE PATH "Path to ar program with LTO-plugin" FORCE)
-      set(CMAKE_NM ${CMAKE_GCC_NM} CACHE PATH "Path to nm program with LTO-plugin" FORCE)
-      set(CMAKE_RANLIB ${CMAKE_GCC_RANLIB} CACHE PATH "Path to ranlib program with LTO-plugin" FORCE)
-      message(STATUS "MDBX indulge Link-Time Optimization by GCC")
-    elseif(CLANG_LTO_AVAILABLE)
-      set(LTO_ENABLED TRUE)
-      set(CMAKE_AR ${CMAKE_CLANG_AR} CACHE PATH "Path to ar program with LTO-plugin" FORCE)
-      set(CMAKE_NM ${CMAKE_CLANG_NM} CACHE PATH "Path to nm program with LTO-plugin" FORCE)
-      set(CMAKE_RANLIB ${CMAKE_CLANG_RANLIB} CACHE PATH "Path to ranlib program with LTO-plugin" FORCE)
-      message(STATUS "MDBX indulge Link-Time Optimization by CLANG")
-    elseif(MSVC_LTO_AVAILABLE)
-      set(LTO_ENABLED TRUE)
-      message(STATUS "MDBX indulge Link-Time Optimization by MSVC")
-    elseif(CMAKE_INTERPROCEDURAL_OPTIMIZATION_AVAILABLE)
-      message(STATUS "MDBX indulge Interprocedural Optimization by CMake")
-      set(CMAKE_INTERPROCEDURAL_OPTIMIZATION TRUE)
-      set(LTO_ENABLED TRUE)
-    else()
-      message(WARNING "Unable to engage interprocedural/LTO optimization.")
-    endif()
-  else()
-    set(CMAKE_INTERPROCEDURAL_OPTIMIZATION FALSE)
-    set(LTO_ENABLED FALSE)
-  endif()
-
-  if(NOT MDBX_AMALGAMATED_SOURCE)
-    find_program(VALGRIND valgrind)
-    if(VALGRIND)
-      # LY: cmake is ugly and nasty.
-      #      - therefore memcheck-options should be defined before including ctest;
-      #      - otherwise ctest may ignore it.
-      set(MEMORYCHECK_SUPPRESSIONS_FILE
-        "${CMAKE_CURRENT_SOURCE_DIR}/test/valgrind_suppress.txt"
-        CACHE FILEPATH "Suppressions file for Valgrind" FORCE)
-      set(MEMORYCHECK_COMMAND_OPTIONS
-        "--trace-children=yes --leak-check=full --track-origins=yes --error-exitcode=42 --error-markers=@ --errors-for-leak-kinds=definite --fair-sched=yes --suppressions=${MEMORYCHECK_SUPPRESSIONS_FILE}"
-        CACHE STRING "Valgrind options" FORCE)
-      set(VALGRIND_COMMAND_OPTIONS "${MEMORYCHECK_COMMAND_OPTIONS}" CACHE STRING "Valgrind options" FORCE)
-    endif()
-
-    # Enable 'make tags' target.
-    find_program(CTAGS ctags)
-    if(CTAGS)
-      add_custom_target(tags COMMAND ${CTAGS} -R -f tags
-        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
-      add_custom_target(ctags DEPENDS tags)
-    endif(CTAGS)
-
-    if(UNIX)
-      find_program(CLANG_FORMAT
-        NAMES clang-format-12 clang-format-11 clang-format-10 clang-format)
-      if(CLANG_FORMAT)
-        execute_process(COMMAND ${CLANG_FORMAT} "--version" OUTPUT_VARIABLE clang_format_version_info)
-        string(REGEX MATCH "version ([0-9]+)\\.([0-9]+)\\.([0-9]+)(.*)?" clang_format_version_info CLANG_FORMAT_VERSION)
-        if(clang_format_version_info AND NOT CLANG_FORMAT_VERSION VERSION_LESS 10.0)
-          # Enable 'make reformat' target.
-          add_custom_target(reformat
-            VERBATIM
-            COMMAND
-            git ls-files |
-            grep -E \\.\(c|cxx|cc|cpp|h|hxx|hpp\)\(\\.in\)?\$ |
-            xargs ${CLANG_FORMAT} -i --style=file
-            WORKING_DIRECTORY ${CMAKE_SOURCE_DIR})
-        endif()
-      endif()
-    endif()
-
-    if(NOT "${PROJECT_BINARY_DIR}" STREQUAL "${PROJECT_SOURCE_DIR}")
-      add_custom_target(distclean)
-      add_custom_command(TARGET distclean
-        COMMAND ${CMAKE_COMMAND} -E remove_directory "${PROJECT_BINARY_DIR}"
-        COMMENT "Removing the build directory and its content")
-    elseif(IS_DIRECTORY .git AND GIT)
-      add_custom_target(distclean)
-      add_custom_command(TARGET distclean
-        WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
-        COMMAND ${GIT} submodule foreach --recursive git clean -f -X -d
-        COMMAND ${GIT} clean -f -X -d
-        COMMENT "Removing all build files from the source directory")
-    endif()
-  endif(NOT MDBX_AMALGAMATED_SOURCE)
-
-  setup_compile_flags()
-endif(SUBPROJECT)
-
-list(FIND CMAKE_C_COMPILE_FEATURES c_std_11 HAS_C11)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_11 HAS_CXX11)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_14 HAS_CXX14)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_17 HAS_CXX17)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_20 HAS_CXX20)
-if(NOT DEFINED MDBX_CXX_STANDARD)
-  if(DEFINED CMAKE_CXX_STANDARD)
-    set(MDBX_CXX_STANDARD ${CMAKE_CXX_STANDARD})
-  elseif(NOT HAS_CXX20 LESS 0)
-    set(MDBX_CXX_STANDARD 20)
-  elseif(NOT HAS_CXX17 LESS 0)
-    set(MDBX_CXX_STANDARD 17)
-  elseif(NOT HAS_CXX14 LESS 0)
-    set(MDBX_CXX_STANDARD 14)
-  elseif(NOT HAS_CXX11 LESS 0)
-    set(MDBX_CXX_STANDARD 11)
-  else()
-    set(MDBX_CXX_STANDARD 98)
-  endif()
-endif()
-if(NOT DEFINED MDBX_C_STANDARD)
-  # MSVC >= 19.28 (Microsoft Visual Studio 16.8) is mad!
-  #               It unable process Windows SDK headers in the C11 mode!
-  if(HAS_C11 LESS 0 OR (MSVC AND MSVC_VERSION GREATER 1927))
-    set(MDBX_C_STANDARD 99)
-  else()
-    set(MDBX_C_STANDARD 11)
-  endif()
-endif()
-
-if(${CMAKE_SYSTEM_NAME} STREQUAL "Windows" AND EXISTS "${MDBX_SOURCE_DIR}/ntdll.def")
-  if(MSVC)
-    if(NOT MSVC_LIB_EXE)
-      # Find lib.exe
-      get_filename_component(CL_NAME ${CMAKE_C_COMPILER} NAME)
-      string(REPLACE cl.exe lib.exe MSVC_LIB_EXE ${CL_NAME})
-      find_program(MSVC_LIB_EXE ${MSVC_LIB_EXE})
-    endif()
-    if(MSVC_LIB_EXE)
-      message(STATUS "Found MSVC's lib tool: ${MSVC_LIB_EXE}")
-      set(MDBX_NTDLL_EXTRA_IMPLIB "${CMAKE_CURRENT_BINARY_DIR}/mdbx_ntdll_extra.lib")
-      add_custom_command(OUTPUT "${MDBX_NTDLL_EXTRA_IMPLIB}"
-        COMMENT "Create extra-import-library for ntdll.dll"
-        MAIN_DEPENDENCY "${MDBX_SOURCE_DIR}/ntdll.def"
-        COMMAND ${MSVC_LIB_EXE} /def:"${MDBX_SOURCE_DIR}/ntdll.def" /out:"${MDBX_NTDLL_EXTRA_IMPLIB}" ${INITIAL_CMAKE_STATIC_LINKER_FLAGS})
-    else()
-      message(WARNING "MSVC's lib tool not found")
-    endif()
-  elseif(MINGW OR MINGW64)
-    if(NOT DLLTOOL)
-      # Find dlltool
-      get_filename_component(GCC_NAME ${CMAKE_C_COMPILER} NAME)
-      string(REPLACE gcc dlltool DLLTOOL_NAME ${GCC_NAME})
-      find_program(DLLTOOL NAMES ${DLLTOOL_NAME})
-    endif()
-    if(DLLTOOL)
-      message(STATUS "Found dlltool: ${DLLTOOL}")
-      set(MDBX_NTDLL_EXTRA_IMPLIB "${CMAKE_CURRENT_BINARY_DIR}/mdbx_ntdll_extra.a")
-      add_custom_command(OUTPUT "${MDBX_NTDLL_EXTRA_IMPLIB}"
-        COMMENT "Create extra-import-library for ntdll.dll"
-        MAIN_DEPENDENCY "${MDBX_SOURCE_DIR}/ntdll.def"
-        COMMAND ${DLLTOOL} -d "${MDBX_SOURCE_DIR}/ntdll.def" -l "${MDBX_NTDLL_EXTRA_IMPLIB}")
-    else()
-      message(WARNING "dlltool not found")
-    endif()
-  endif()
-
-  if(MDBX_NTDLL_EXTRA_IMPLIB)
-    # LY: Sometimes CMake requires a nightmarish magic for simple things.
-    # 1) create a target out of the library compilation result
-    add_custom_target(ntdll_extra_target DEPENDS "${MDBX_NTDLL_EXTRA_IMPLIB}")
-    # 2) create an library target out of the library compilation result
-    add_library(ntdll_extra STATIC IMPORTED GLOBAL)
-    add_dependencies(ntdll_extra ntdll_extra_target)
-    # 3) specify where the library is (and where to find the headers)
-    set_target_properties(ntdll_extra
-      PROPERTIES
-      IMPORTED_LOCATION "${MDBX_NTDLL_EXTRA_IMPLIB}")
-  endif()
-endif()
-
-################################################################################
-################################################################################
-#
-#           ####   #####    #####     #     ####   #    #   ####
-#          #    #  #    #     #       #    #    #  ##   #  #
-#          #    #  #    #     #       #    #    #  # #  #   ####
-#          #    #  #####      #       #    #    #  #  # #       #
-#          #    #  #          #       #    #    #  #   ##  #    #
-#           ####   #          #       #     ####   #    #   ####
-#
-
-set(MDBX_BUILD_OPTIONS ENABLE_ASAN MDBX_USE_VALGRIND ENABLE_GPROF ENABLE_GCOV)
-macro(add_mdbx_option NAME DESCRIPTION DEFAULT)
-  list(APPEND MDBX_BUILD_OPTIONS ${NAME})
-  if(NOT ${DEFAULT} STREQUAL "AUTO")
-    option(${NAME} "${DESCRIPTION}" ${DEFAULT})
-  elseif(NOT DEFINED ${NAME})
-    set(${NAME}_AUTO ON)
-  endif()
-endmacro()
-
-if(IOS)
-  set(MDBX_BUILD_TOOLS_DEFAULT OFF)
-  if(NOT_SUBPROJECT)
-    cmake_policy(SET CMP0006 OLD)
-    set(CMAKE_XCODE_ATTRIBUTE_CODE_SIGNING_ALLOWED "NO")
-  endif()
-else()
-  set(MDBX_BUILD_TOOLS_DEFAULT ON)
-endif()
-
-add_mdbx_option(MDBX_INSTALL_STATIC "Build and install libmdbx for static linking" OFF)
-add_mdbx_option(MDBX_BUILD_SHARED_LIBRARY "Build libmdbx as shared library (DLL)" ${BUILD_SHARED_LIBS})
-add_mdbx_option(MDBX_BUILD_TOOLS "Build MDBX tools (mdbx_chk/stat/dump/load/copy)" ${MDBX_BUILD_TOOLS_DEFAULT})
-CMAKE_DEPENDENT_OPTION(MDBX_INSTALL_MANPAGES "Install man-pages for MDBX tools (mdbx_chk/stat/dump/load/copy)" ON MDBX_BUILD_TOOLS OFF)
-add_mdbx_option(MDBX_TXN_CHECKOWNER "Checking transaction matches the calling thread inside libmdbx's API" ON)
-add_mdbx_option(MDBX_ENV_CHECKPID "Paranoid checking PID inside libmdbx's API" AUTO)
-mark_as_advanced(MDBX_ENV_CHECKPID)
-if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
-  add_mdbx_option(MDBX_DISABLE_GNU_SOURCE "Don't use GNU/Linux libc extensions" OFF)
-  mark_as_advanced(MDBX_DISABLE_GNU_SOURCE)
-endif()
-if(${CMAKE_SYSTEM_NAME} STREQUAL "Darwin" OR IOS)
-  add_mdbx_option(MDBX_OSX_SPEED_INSTEADOF_DURABILITY "Disable use fcntl(F_FULLFSYNC) in favor of speed" OFF)
-  mark_as_advanced(MDBX_OSX_SPEED_INSTEADOF_DURABILITY)
-endif()
-if(${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
-  if(MDBX_NTDLL_EXTRA_IMPLIB)
-    add_mdbx_option(MDBX_AVOID_CRT "Avoid dependence from MSVC CRT and use ntdll.dll instead" OFF)
-  endif()
-  add_mdbx_option(MDBX_CONFIG_MANUAL_TLS_CALLBACK
-    "Provide mdbx_dll_handler() for manual initialization" OFF)
-  mark_as_advanced(MDBX_CONFIG_MANUAL_TLS_CALLBACK)
-else()
-  add_mdbx_option(MDBX_USE_OFDLOCKS "Use Open file description locks (aka OFD locks, non-POSIX)" AUTO)
-  mark_as_advanced(MDBX_USE_OFDLOCKS)
-endif()
-add_mdbx_option(MDBX_LOCKING "Locking method (Win32=-1, SysV=5, POSIX=1988, POSIX=2001, POSIX=2008, Futexes=1995)" AUTO)
-mark_as_advanced(MDBX_LOCKING)
-add_mdbx_option(MDBX_TRUST_RTC "Does a system have battery-backed Real-Time Clock or just a fake" AUTO)
-mark_as_advanced(MDBX_TRUST_RTC)
-option(MDBX_FORCE_ASSERTIONS "Force enable assertion checking" OFF)
-
-if(NOT MDBX_AMALGAMATED_SOURCE)
-  add_mdbx_option(MDBX_ALLOY_BUILD "Build MDBX library through single/alloyed object file" ON)
-endif()
-
-if((MDBX_BUILD_TOOLS OR MDBX_ENABLE_TESTS) AND MDBX_BUILD_SHARED_LIBRARY)
-  add_mdbx_option(MDBX_LINK_TOOLS_NONSTATIC "Link MDBX tools with non-static libmdbx" OFF)
-else()
-  unset(MDBX_LINK_TOOLS_NONSTATIC CACHE)
-endif()
-
-if(CMAKE_CXX_COMPILER_LOADED AND MDBX_CXX_STANDARD GREATER_EQUAL 11 AND MDBX_CXX_STANDARD LESS 83)
-  if(NOT MDBX_AMALGAMATED_SOURCE)
-    option(MDBX_ENABLE_TESTS "Build MDBX tests" ${BUILD_TESTING})
-  endif()
-  if(NOT MDBX_AVOID_CRT
-      AND NOT (CMAKE_COMPILER_IS_GNUCXX AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.8)
-      AND NOT (CMAKE_COMPILER_IS_CLANG AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4)
-      AND NOT (MSVC AND MSVC_VERSION LESS 1900))
-    option(MDBX_BUILD_CXX "Build C++ portion" ON)
-  else()
-    set(MDBX_BUILD_CXX FALSE)
-  endif()
-else()
-  set(MDBX_BUILD_CXX FALSE)
-  set(MDBX_ENABLE_TESTS FALSE)
-endif()
-
-################################################################################
-################################################################################
-
-if(MDBX_BUILD_CXX AND NOT CMAKE_CXX_COMPILER_LOADED)
-  message(FATAL_ERROR "MDBX_BUILD_CXX=${MDBX_BUILD_CXX}: The C++ compiler is required to build the C++API.")
-endif()
-
-# Get version
-fetch_version(MDBX "${CMAKE_CURRENT_SOURCE_DIR}" FALSE)
-message(STATUS "libmdbx version is ${MDBX_VERSION}")
-
-# sources list
-set(LIBMDBX_PUBLIC_HEADERS mdbx.h)
-set(LIBMDBX_SOURCES mdbx.h "${CMAKE_CURRENT_BINARY_DIR}/config.h")
-if(MDBX_AMALGAMATED_SOURCE)
-  list(APPEND LIBMDBX_SOURCES mdbx.c)
-else()
-  # generate version file
-  configure_file("${MDBX_SOURCE_DIR}/version.c.in"
-    "${CMAKE_CURRENT_BINARY_DIR}/version.c" ESCAPE_QUOTES)
-  file(SHA256 "${CMAKE_CURRENT_BINARY_DIR}/version.c" MDBX_SOURCERY_DIGEST)
-  string(MAKE_C_IDENTIFIER "${MDBX_GIT_DESCRIBE}" MDBX_SOURCERY_SUFFIX)
-  set(MDBX_BUILD_SOURCERY "${MDBX_SOURCERY_DIGEST}_${MDBX_SOURCERY_SUFFIX}")
-
-  if(MDBX_ALLOY_BUILD)
-    list(APPEND LIBMDBX_SOURCES "${MDBX_SOURCE_DIR}/alloy.c")
-    include_directories("${MDBX_SOURCE_DIR}" "${CMAKE_CURRENT_BINARY_DIR}")
-  else()
-    list(APPEND LIBMDBX_SOURCES
-      "${CMAKE_CURRENT_BINARY_DIR}/version.c"
-      "${MDBX_SOURCE_DIR}/options.h" "${MDBX_SOURCE_DIR}/defs.h"
-      "${MDBX_SOURCE_DIR}/internals.h" "${MDBX_SOURCE_DIR}/osal.h"
-      "${MDBX_SOURCE_DIR}/core.c" "${MDBX_SOURCE_DIR}/osal.c"
-      "${MDBX_SOURCE_DIR}/lck-posix.c" "${MDBX_SOURCE_DIR}/lck-windows.c")
-    include_directories("${MDBX_SOURCE_DIR}")
-  endif()
-endif(MDBX_AMALGAMATED_SOURCE)
-if(MDBX_BUILD_CXX)
-  message(STATUS "Use C${MDBX_C_STANDARD} and C++${MDBX_CXX_STANDARD} for libmdbx")
-  list(APPEND LIBMDBX_PUBLIC_HEADERS mdbx.h++)
-  list(APPEND LIBMDBX_SOURCES "${MDBX_SOURCE_DIR}/mdbx.c++" mdbx.h++)
-else()
-  message(STATUS "Use C${MDBX_C_STANDARD} for libmdbx but C++ portion is disabled")
-endif()
-
-macro(target_setup_options TARGET)
-  if(DEFINED INTERPROCEDURAL_OPTIMIZATION)
-    set_target_properties(${TARGET} PROPERTIES
-      INTERPROCEDURAL_OPTIMIZATION $<BOOL:${INTERPROCEDURAL_OPTIMIZATION}>)
-  endif()
-  set_target_properties(${TARGET} PROPERTIES
-    C_STANDARD ${MDBX_C_STANDARD} C_STANDARD_REQUIRED ON)
-  if(MDBX_BUILD_CXX)
-    set_target_properties(${TARGET} PROPERTIES
-      CXX_STANDARD ${MDBX_CXX_STANDARD} CXX_STANDARD_REQUIRED ON)
-  endif()
-  if(CC_HAS_FASTMATH)
-    target_compile_options(${TARGET} PRIVATE "-ffast-math")
-  endif()
-  if(CC_HAS_VISIBILITY)
-    target_compile_options(${TARGET} PRIVATE "-fvisibility=hidden")
-  endif()
-  if(BUILD_FOR_NATIVE_CPU AND CC_HAS_ARCH_NATIVE)
-    target_compile_options(${TARGET} PUBLIC "-march=native")
-  endif()
-endmacro()
-
-macro(libmdbx_setup_libs TARGET MODE)
-  target_link_libraries(${TARGET} ${MODE} Threads::Threads)
-  if(${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
-    target_link_libraries(${TARGET} ${MODE} ntdll.lib)
-    if(MDBX_NTDLL_EXTRA_IMPLIB AND MDBX_AVOID_CRT)
-      target_link_libraries(${TARGET} ${MODE} ntdll_extra)
-    endif()
-  elseif(${CMAKE_SYSTEM_NAME} STREQUAL "SunOS" OR ${CMAKE_SYSTEM_NAME} STREQUAL "Solaris")
-    target_link_libraries(${TARGET} ${MODE} kstat)
-  elseif(${CMAKE_SYSTEM_NAME} STREQUAL "Android")
-    target_link_libraries(${TARGET} ${MODE} log)
-  endif()
-  if(LIBCXX_FILESYSTEM AND MDBX_BUILD_CXX)
-    target_link_libraries(${TARGET} ${MODE} ${LIBCXX_FILESYSTEM})
-  endif()
-endmacro()
-
-# build static library
-if(MDBX_INSTALL_STATIC)
-  add_library(mdbx-static STATIC ${LIBMDBX_SOURCES})
-else()
-  add_library(mdbx-static STATIC EXCLUDE_FROM_ALL ${LIBMDBX_SOURCES})
-endif()
-set_target_properties(mdbx-static PROPERTIES PUBLIC_HEADER "${LIBMDBX_PUBLIC_HEADERS}")
-target_compile_definitions(mdbx-static PRIVATE MDBX_BUILD_SHARED_LIBRARY=0)
-target_setup_options(mdbx-static)
-libmdbx_setup_libs(mdbx-static INTERFACE)
-if(MDBX_BUILD_SHARED_LIBRARY)
-  set_target_properties(mdbx-static PROPERTIES OUTPUT_NAME mdbx-static)
-else()
-  set_target_properties(mdbx-static PROPERTIES OUTPUT_NAME mdbx)
-endif()
-
-################################################################################
-
-# build shared library
-if(MDBX_BUILD_SHARED_LIBRARY)
-  add_library(mdbx SHARED ${LIBMDBX_SOURCES})
-  set_target_properties(mdbx PROPERTIES PUBLIC_HEADER "${LIBMDBX_PUBLIC_HEADERS}")
-  target_compile_definitions(mdbx PRIVATE LIBMDBX_EXPORTS MDBX_BUILD_SHARED_LIBRARY=1 INTERFACE LIBMDBX_IMPORTS)
-  target_setup_options(mdbx)
-  libmdbx_setup_libs(mdbx PRIVATE)
-  if(MSVC)
-    if(MDBX_NTDLL_EXTRA_IMPLIB AND MDBX_AVOID_CRT)
-      set_property(TARGET mdbx PROPERTY LINKER_FLAGS "/NODEFAULTLIB")
-    else()
-      set_property(TARGET mdbx PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>DLL")
-    endif()
-  endif()
-  if(CC_HAS_VISIBILITY AND (LTO_ENABLED OR INTERPROCEDURAL_OPTIMIZATION))
-    set_target_properties(mdbx PROPERTIES LINK_FLAGS "-fvisibility=hidden")
-  endif()
-  list(APPEND MDBX_BUILD_FLAGS ${CMAKE_SHARED_LINKER_FLAGS})
-endif()
-
-if(MDBX_BUILD_SHARED_LIBRARY AND MDBX_LINK_TOOLS_NONSTATIC)
-  set(TOOL_MDBX_LIB mdbx)
-
-  # use, i.e. don't skip the full RPATH for the build tree
-  set(CMAKE_SKIP_BUILD_RPATH FALSE)
-
-  # when building, don't use the install RPATH already (but later on when installing)
-  set(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE)
-
-  # add the automatically determined parts of the RPATH
-  # which point to directories outside the build tree to the install RPATH
-  set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
-
-  # the RPATH to be used when installing, but only if it's not a system directory
-  list(FIND CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES "${CMAKE_INSTALL_PREFIX}/lib" isSystemDir)
-  if(isSystemDir EQUAL -1)
-    if(${CMAKE_SYSTEM_NAME} STREQUAL "Darwin")
-      set(CMAKE_INSTALL_RPATH "@executable_path/../lib")
-    else()
-      set(CMAKE_INSTALL_RPATH "\$ORIGIN/../lib")
-    endif()
-  endif()
-else()
-  set(TOOL_MDBX_LIB mdbx-static)
-endif()
-
-# build mdbx-tools
-if(MDBX_BUILD_TOOLS)
-  if(NOT MDBX_AMALGAMATED_SOURCE AND ${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
-    set(WINGETOPT_SRC ${MDBX_SOURCE_DIR}/wingetopt.c ${MDBX_SOURCE_DIR}/wingetopt.h)
-  else()
-    set(WINGETOPT_SRC "")
-  endif()
-
-  foreach(TOOL mdbx_chk mdbx_copy mdbx_stat mdbx_dump mdbx_load)
-    add_executable(${TOOL} mdbx.h ${MDBX_SOURCE_DIR}/${TOOL}.c ${WINGETOPT_SRC})
-    if(MDBX_C_STANDARD)
-      set_target_properties(${TOOL} PROPERTIES
-        C_STANDARD ${MDBX_C_STANDARD} C_STANDARD_REQUIRED ON)
-    endif()
-    target_setup_options(${TOOL})
-    target_link_libraries(${TOOL} ${TOOL_MDBX_LIB})
-  endforeach()
-  if(LIB_MATH)
-    target_link_libraries(mdbx_chk ${LIB_MATH})
-    target_link_libraries(mdbx_stat ${LIB_MATH})
-  endif()
-endif()
-
-################################################################################
-
-# mdbx-shared-lib installation
-if(NOT DEFINED MDBX_DLL_INSTALL_DESTINATION)
-  if(WIN32)
-    set(MDBX_DLL_INSTALL_DESTINATION bin)
-  else()
-    set(MDBX_DLL_INSTALL_DESTINATION lib)
-  endif()
-endif()
-if(MDBX_BUILD_SHARED_LIBRARY)
-  if(CMAKE_VERSION VERSION_LESS 3.12)
-    install(TARGETS mdbx EXPORT libmdbx
-      LIBRARY DESTINATION ${MDBX_DLL_INSTALL_DESTINATION} COMPONENT runtime
-      OBJECTS DESTINATION lib COMPONENT devel
-      ARCHIVE DESTINATION lib COMPONENT devel
-      PUBLIC_HEADER DESTINATION include COMPONENT devel
-      INCLUDES DESTINATION include COMPONENT devel)
-  else()
-    install(TARGETS mdbx EXPORT libmdbx
-      LIBRARY DESTINATION ${MDBX_DLL_INSTALL_DESTINATION} COMPONENT runtime
-      NAMELINK_COMPONENT devel
-      OBJECTS DESTINATION lib COMPONENT devel
-      ARCHIVE DESTINATION lib COMPONENT devel
-      PUBLIC_HEADER DESTINATION include COMPONENT devel
-      INCLUDES DESTINATION include COMPONENT devel)
-  endif()
-endif(MDBX_BUILD_SHARED_LIBRARY)
-
-# mdbx-tools installation
-if(MDBX_BUILD_TOOLS)
-  if(NOT DEFINED MDBX_TOOLS_INSTALL_DESTINATION)
-    set(MDBX_TOOLS_INSTALL_DESTINATION bin)
-  endif()
-  install(
-    TARGETS
-    mdbx_chk
-    mdbx_stat
-    mdbx_copy
-    mdbx_dump
-    mdbx_load
-    RUNTIME
-    DESTINATION ${MDBX_TOOLS_INSTALL_DESTINATION}
-    COMPONENT runtime)
-  if(MDBX_INSTALL_MANPAGES)
-    if(NOT DEFINED MDBX_MAN_INSTALL_DESTINATION)
-      set(MDBX_MAN_INSTALL_DESTINATION man/man1)
-    endif()
-    install(
-      FILES
-      "${MDBX_SOURCE_DIR}/man1/mdbx_chk.1"
-      "${MDBX_SOURCE_DIR}/man1/mdbx_stat.1"
-      "${MDBX_SOURCE_DIR}/man1/mdbx_copy.1"
-      "${MDBX_SOURCE_DIR}/man1/mdbx_dump.1"
-      "${MDBX_SOURCE_DIR}/man1/mdbx_load.1"
-      DESTINATION ${MDBX_MAN_INSTALL_DESTINATION}
-      COMPONENT doc)
-  endif()
-endif(MDBX_BUILD_TOOLS)
-
-# mdbx-static-lib installation
-if(MDBX_INSTALL_STATIC)
-  if(CMAKE_VERSION VERSION_LESS 3.12)
-    install(TARGETS mdbx-static EXPORT libmdbx
-      LIBRARY DESTINATION lib COMPONENT devel
-      OBJECTS DESTINATION lib COMPONENT devel
-      ARCHIVE DESTINATION lib COMPONENT devel
-      PUBLIC_HEADER DESTINATION include COMPONENT devel
-      INCLUDES DESTINATION include COMPONENT devel)
-  else()
-    install(TARGETS mdbx-static EXPORT libmdbx
-      LIBRARY DESTINATION lib COMPONENT devel
-      NAMELINK_COMPONENT devel
-      OBJECTS DESTINATION lib COMPONENT devel
-      ARCHIVE DESTINATION lib COMPONENT devel
-      PUBLIC_HEADER DESTINATION include COMPONENT devel
-      INCLUDES DESTINATION include COMPONENT devel)
-  endif()
-endif(MDBX_INSTALL_STATIC)
-
-################################################################################
-
-# collect options & build info
-string(TIMESTAMP MDBX_BUILD_TIMESTAMP UTC)
-set(MDBX_BUILD_FLAGS ${CMAKE_C_FLAGS})
-if(MDBX_BUILD_CXX)
-  set(MDBX_BUILD_FLAGS ${CMAKE_CXX_FLAGS})
-endif()
-
-# append cmake's build-type flags and defines
-if(NOT CMAKE_CONFIGURATION_TYPES)
-  list(APPEND MDBX_BUILD_FLAGS ${CMAKE_C_FLAGS_${CMAKE_BUILD_TYPE_UPPERCASE}})
-  if(MDBX_BUILD_CXX)
-    list(APPEND MDBX_BUILD_FLAGS ${CMAKE_CXX_FLAGS_${CMAKE_BUILD_TYPE_UPPERCASE}})
-  endif()
-endif()
-
-# choice target to fetch definitions and options
-if(MDBX_BUILD_SHARED_LIBRARY)
-  set(target4fetch mdbx)
-else()
-  set(target4fetch mdbx-static)
-endif()
-
-# get definitions
-get_target_property(defs_list ${target4fetch} COMPILE_DEFINITIONS)
-if(defs_list)
-  list(APPEND MDBX_BUILD_FLAGS ${defs_list})
-endif()
-
-# get target compile options
-get_target_property(options_list ${target4fetch} COMPILE_OPTIONS)
-if(options_list)
-  list(APPEND MDBX_BUILD_FLAGS ${options_list})
-endif()
-
-list(REMOVE_DUPLICATES MDBX_BUILD_FLAGS)
-string(REPLACE ";" " " MDBX_BUILD_FLAGS "${MDBX_BUILD_FLAGS}")
-if(CMAKE_CONFIGURATION_TYPES)
-  # add dynamic part via per-configuration define
-  message(STATUS "MDBX Compile Flags: ${MDBX_BUILD_FLAGS} <AND CONFIGURATION DEPENDENT>")
-  add_definitions(-DMDBX_BUILD_FLAGS_CONFIG="$<$<CONFIG:Debug>:${CMAKE_C_FLAGS_DEBUG} ${CMAKE_C_DEFINES_DEBUG}>$<$<CONFIG:Release>:${CMAKE_C_FLAGS_RELEASE} ${CMAKE_C_DEFINES_RELEASE}>$<$<CONFIG:RelWithDebInfo>:${CMAKE_C_FLAGS_RELWITHDEBINFO} ${CMAKE_C_DEFINES_RELWITHDEBINFO}>$<$<CONFIG:MinSizeRel>:${CMAKE_C_FLAGS_MINSIZEREL} ${CMAKE_C_DEFINES_MINSIZEREL}>")
-else()
-  message(STATUS "MDBX Compile Flags: ${MDBX_BUILD_FLAGS}")
-endif()
-
-# get compiler info
-execute_process(COMMAND sh -c "${CMAKE_C_COMPILER} --version | head -1"
-  OUTPUT_VARIABLE MDBX_BUILD_COMPILER
-  OUTPUT_STRIP_TRAILING_WHITESPACE
-  ERROR_QUIET
-  RESULT_VARIABLE rc)
-if(rc OR NOT MDBX_BUILD_COMPILER)
-  string(STRIP "${CMAKE_C_COMPILER_ID}-${CMAKE_C_COMPILER_VERSION}" MDBX_BUILD_COMPILER)
-endif()
-
-# make a build-target triplet
-if(CMAKE_C_COMPILER_TARGET)
-  set(MDBX_BUILD_TARGET "${CMAKE_C_COMPILER_TARGET}")
-elseif(CMAKE_C_PLATFORM_ID AND NOT CMAKE_C_PLATFORM_ID STREQUAL CMAKE_SYSTEM_NAME)
-  string(STRIP "${CMAKE_C_PLATFORM_ID}-${CMAKE_SYSTEM_NAME}" MDBX_BUILD_TARGET)
-elseif(CMAKE_LIBRARY_ARCHITECTURE)
-  string(STRIP "${CMAKE_LIBRARY_ARCHITECTURE}-${CMAKE_SYSTEM_NAME}" MDBX_BUILD_TARGET)
-elseif(CMAKE_GENERATOR_PLATFORM AND NOT CMAKE_C_PLATFORM_ID STREQUAL CMAKE_SYSTEM_NAME)
-  string(STRIP "${CMAKE_GENERATOR_PLATFORM}-${CMAKE_SYSTEM_NAME}" MDBX_BUILD_TARGET)
-elseif(CMAKE_SYSTEM_ARCH)
-  string(STRIP "${CMAKE_SYSTEM_ARCH}-${CMAKE_SYSTEM_NAME}" MDBX_BUILD_TARGET)
-else()
-  string(STRIP "${CMAKE_SYSTEM_PROCESSOR}-${CMAKE_SYSTEM_NAME}" MDBX_BUILD_TARGET)
-endif()
-
-# provide build-type
-if(CMAKE_CONFIGURATION_TYPES)
-  # via per-configuration define
-  add_definitions(-DMDBX_BUILD_TYPE="$<CONFIG>")
-  set(MDBX_BUILD_TYPE "<CONFIGURATION DEPENDENT>")
-else()
-  set(MDBX_BUILD_TYPE ${CMAKE_BUILD_TYPE})
-endif()
-
-# options
-set(options VERSION C_COMPILER CXX_COMPILER MDBX_BUILD_TARGET MDBX_BUILD_TYPE)
-foreach(item IN LISTS options)
-  if(DEFINED ${item})
-    set(value "${${item}}")
-  elseif(DEFINED MDBX_${item})
-    set(item MDBX_${item})
-    set(value "${${item}}")
-  elseif(DEFINED CMAKE_${item})
-    set(item CMAKE_${item})
-    set(value "${${item}}")
-  else()
-    set(value "undefined")
-  endif()
-  message(STATUS "${item}: ${value}")
-endforeach(item)
-
-# provide config.h for library build info
-configure_file("${MDBX_SOURCE_DIR}/config.h.in"
-  "${CMAKE_CURRENT_BINARY_DIR}/config.h" ESCAPE_QUOTES)
-add_definitions(-DMDBX_CONFIG_H="${CMAKE_CURRENT_BINARY_DIR}/config.h")
-
-################################################################################
-
-if(NOT MDBX_AMALGAMATED_SOURCE AND MDBX_ENABLE_TESTS)
-  if(NOT CMAKE_CXX_COMPILER_LOADED)
-    message(FATAL_ERROR "MDBX_ENABLE_TESTS=${MDBX_ENABLE_TESTS}: The C++ compiler is required to build the tests.")
-  endif()
-  add_subdirectory(test)
-endif()
-
-################################################################################
-
-set(PACKAGE "libmdbx")
-set(CPACK_PACKAGE_VERSION_MAJOR ${MDBX_VERSION_MAJOR})
-set(CPACK_PACKAGE_VERSION_MINOR ${MDBX_VERSION_MINOR})
-set(CPACK_PACKAGE_VERSION_PATCH ${MDBX_VERSION_RELEASE})
-set(CPACK_PACKAGE_VERSION_COMMIT ${MDBX_VERSION_REVISION})
-set(PACKAGE_VERSION "${CPACK_PACKAGE_VERSION_MAJOR}.${CPACK_PACKAGE_VERSION_MINOR}.${CPACK_PACKAGE_VERSION_PATCH}.${CPACK_PACKAGE_VERSION_COMMIT}")
-message(STATUS "libmdbx package version is ${PACKAGE_VERSION}")
-
-cmake_policy(POP)
diff --git a/plugins/Dbx_mdbx/src/libmdbx/ChangeLog.md b/plugins/Dbx_mdbx/src/libmdbx/ChangeLog.md
deleted file mode 100644
index 50b911f5a7..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/ChangeLog.md
+++ /dev/null
@@ -1,305 +0,0 @@
-ChangeLog
----------
-
-## v0.9.3 (in development) scheduled at 2021-02-23
-
-TODO:
- - Engage new terminology (https://github.com/erthink/libmdbx/issues/137).
- - Rework/speedup the implementation of the dirty page list (lazy compactification, lazy sorting via merge).
- - Resolve few TODOs (https://github.com/erthink/libmdbx/issues/124, https://github.com/erthink/libmdbx/issues/127,
-   https://github.com/erthink/libmdbx/issues/132, https://github.com/erthink/libmdbx/issues/115).
- - Finalize C++ API (few typos and trivia bugs are still likely for now).
- - Packages for [ROSA Linux](https://www.rosalinux.ru/), [ALT Linux](https://www.altlinux.org/), Fedora/RHEL, Debian/Ubuntu.
-
-Acknowledgements:
-
- - [Mahlon E. Smith](http://www.martini.nu/) for [FreeBSD port of libmdbx](https://svnweb.freebsd.org/ports/head/databases/mdbx/).
- - [장세연](http://www.castis.com) for bug fixing and PR.
- - [Clément Renault](https://github.com/Kerollmops/heed) for [Heed](https://github.com/Kerollmops/heed) fully typed Rust wrapper.
- - [Alex Sharov](https://github.com/AskAlexSharov) for bug reporting.
- - [Noel Kuntze](https://github.com/Thermi) for bug reporting.
-
-Removed options and features:
-
- - Drop `MDBX_HUGE_TRANSACTIONS` build-option (now no longer required).
-
-New features:
-
- - Package for FreeBSD is available now by Mahlon E. Smith.
- - New API functions to get/set various options (https://github.com/erthink/libmdbx/issues/128):
-    - the maximum number of named databases for the environment;
-    - the maximum number of threads/reader slots;
-    - threshold (since the last unsteady commit) to force flush the data buffers to disk;
-    - relative period (since the last unsteady commit) to force flush the data buffers to disk;
-    - limit to grow a list of reclaimed/recycled page's numbers for finding a sequence of contiguous pages for large data items;
-    - limit to grow a cache of dirty pages for reuse in the current transaction;
-    - limit of a pre-allocated memory items for dirty pages;
-    - limit of dirty pages for a write transaction;
-    - initial allocation size for dirty pages list of a write transaction;
-    - maximal part of the dirty pages may be spilled when necessary;
-    - minimal part of the dirty pages should be spilled when necessary;
-    - how much of the parent transaction dirty pages will be spilled while start each child transaction;
- - Unlimited/Dynamic size of retired and dirty page lists (https://github.com/erthink/libmdbx/issues/123).
- - Added `-p` option (purge subDB before loading) to `mdbx_load` tool.
- - Reworked spilling of large transaction and committing of nested transactions:
-    - page spilling code reworked to avoid the flaws and bugs inherited from LMDB;
-    - limit for number of dirty pages now is controllable at runtime;
-    - a spilled pages, including overflow/large pages, now can be reused and refunded/compactified in nested transactions;
-    - more effective refunding/compactification especially for the loosed page cache.
- - Added `MDBX_ENABLE_REFUND` and `MDBX_PNL_ASCENDING` internal/advanced build options.
- - Added `mdbx_default_pagesize()` function.
- - Better support architectures with a weak/relaxed memory consistency model (ARM, AARCH64, PPC, MIPS, RISC-V, etc) by means [C11 atomics](https://en.cppreference.com/w/c/atomic).
-
-Fixes:
-
- - Fixed missing cleanup (null assigned) in the C++ commit/abort (https://github.com/erthink/libmdbx/pull/143).
- - Fixed `mdbx_realloc()` for case of nullptr and `MDBX_AVOID_CRT=ON` for Windows.
- - Fixed the possibility to use invalid and renewed (closed & re-opened, dropped & re-created) DBI-handles (https://github.com/erthink/libmdbx/issues/146).
- - Fixed 4-byte aligned access to 64-bit integers, including access to the `bootid` meta-page's field (https://github.com/erthink/libmdbx/issues/153).
- - Fixed minor/potential memory leak during page flushing and unspilling.
- - Fixed handling states of cursors's and subDBs's for nested transactions.
- - Fixed page leak in extra rare case the list of retired pages changed during update GC on transaction commit.
- - Fixed assertions to avoid false-positive UB detection by CLANG/LLVM (https://github.com/erthink/libmdbx/issues/153).
- - Fixed `MDBX_TXN_FULL` and regressive `MDBX_KEYEXIST` during large transaction commit with `MDBX_LIFORECLAIM` (https://github.com/erthink/libmdbx/issues/123).
- - Fixed auto-recovery (`weak->steady` with the same boot-id) when Database size at last weak checkpoint is large than at last steady checkpoint.
- - Fixed operation on systems with unusual small/large page size, including PowerPC (https://github.com/erthink/libmdbx/issues/157).
-
-
-## v0.9.2 at 2020-11-27
-
-Acknowledgements:
-
- - Jens Alfke (Mobile Architect at [Couchbase](https://www.couchbase.com/)) for [NimDBX](https://github.com/snej/nimdbx).
- - Clément Renault (CTO at [MeiliSearch](https://www.meilisearch.com/)) for [mdbx-rs](https://github.com/Kerollmops/mdbx-rs).
- - Alex Sharov (Go-Lang Teach Lead at [TurboGeth/Ethereum](https://ethereum.org/)) for an extreme test cases and bug reporting.
- - George Hazan (CTO at [Miranda NG](https://www.miranda-ng.org/)) for bug reporting.
- - [Positive Technologies](https://www.ptsecurity.com/) for funding and [The Standoff](https://standoff365.com/).
-
-Added features:
-
- - Provided package for [buildroot](https://buildroot.org/).
- - Binding for Nim is [available](https://github.com/snej/nimdbx) now by Jens Alfke.
- - Added `mdbx_env_delete()` for deletion an environment files in a proper and multiprocess-safe way.
- - Added `mdbx_txn_commit_ex()` with collecting latency information.
- - Fast completion pure nested transactions.
- - Added `LIBMDBX_INLINE_API` macro and inline versions of some API functions.
- - Added `mdbx_cursor_copy()` function.
- - Extended tests for checking cursor tracking.
- - Added `MDBX_SET_LOWERBOUND` operation for `mdbx_cursor_get()`.
-
-Fixes:
-
- - Fixed missing installation of `mdbx.h++`.
- - Fixed use of obsolete `__noreturn`.
- - Fixed use of `yield` instruction on ARM if unsupported.
- - Added pthread workaround for buggy toolchain/cmake/buildroot.
- - Fixed use of `pthread_yield()` for non-GLIBC.
- - Fixed use of `RegGetValueA()` on Windows 2000/XP.
- - Fixed use of `GetTickCount64()` on Windows 2000/XP.
- - Fixed opening DB on a network shares (in the exclusive mode).
- - Fixed copy&paste typos.
- - Fixed minor false-positive GCC warning.
- - Added workaround for broken `DEFINE_ENUM_FLAG_OPERATORS` from Windows SDK.
- - Fixed cursor state after multimap/dupsort repeated deletes (https://github.com/erthink/libmdbx/issues/121).
- - Added `SIGPIPE` suppression for internal thread during `mdbx_env_copy()`.
- - Fixed extra-rare `MDBX_KEY_EXIST` error during `mdbx_commit()` (https://github.com/erthink/libmdbx/issues/131).
- - Fixed spilled pages checking (https://github.com/erthink/libmdbx/issues/126).
- - Fixed `mdbx_load` for 'plain text' and without `-s name` cases (https://github.com/erthink/libmdbx/issues/136).
- - Fixed save/restore/commit of cursors for nested transactions.
- - Fixed cursors state in rare/special cases (move next beyond end-of-data, after deletion and so on).
- - Added workaround for MSVC 19.28 (Visual Studio 16.8) (but may still hang during compilation).
- - Fixed paranoidal Clang C++ UB for bitwise operations with flags defined by enums.
- - Fixed large pages checking (for compatibility and to avoid false-positive errors from `mdbx_chk`).
- - Added workaround for Wine (https://github.com/miranda-ng/miranda-ng/issues/1209).
- - Fixed `ERROR_NOT_SUPPORTED` while opening DB by UNC pathnames (https://github.com/miranda-ng/miranda-ng/issues/2627).
- - Added handling `EXCEPTION_POSSIBLE_DEADLOCK` condition for Windows.
-
-
-## v0.9.1 2020-09-30
-
-Added features:
-
- - Preliminary C++ API with support for C++17 polymorphic allocators.
- - [Online C++ API reference](https://erthink.github.io/libmdbx/) by Doxygen.
- - Quick reference for Insert/Update/Delete operations.
- - Explicit `MDBX_SYNC_DURABLE` to sync modes for API clarity.
- - Explicit `MDBX_ALLDUPS` and `MDBX_UPSERT` for API clarity.
- - Support for read transactions preparation (`MDBX_TXN_RDONLY_PREPARE` flag).
- - Support for cursor preparation/(pre)allocation and reusing (`mdbx_cursor_create()` and `mdbx_cursor_bind()` functions).
- - Support for checking database using specified meta-page (see `mdbx_chk -h`).
- - Support for turn to the specific meta-page after checking (see `mdbx_chk -h`).
- - Support for explicit reader threads (de)registration.
- - The `mdbx_txn_break()` function to explicitly mark a transaction as broken.
- - Improved handling of corrupted databases by `mdbx_chk` utility and `mdbx_walk_tree()` function.
- - Improved DB corruption detection by checking parent-page-txnid.
- - Improved opening large DB (> 4Gb) from 32-bit code.
- - Provided `pure-function` and `const-function` attributes to C API.
- - Support for user-settable context for transactions & cursors.
- - Revised API and documentation related to Handle-Slow-Readers callback feature.
-
-Deprecated functions and flags:
-
- - For clarity and API simplification the `MDBX_MAPASYNC` flag is deprecated.
-   Just use `MDBX_SAFE_NOSYNC` or `MDBX_UTTERLY_NOSYNC` instead of it.
- - `MDBX_oom_func`, `mdbx_env_set_oomfunc()` and `mdbx_env_get_oomfunc()`
-   replaced with `MDBX_hsr_func`, `mdbx_env_get_hsr` and `mdbx_env_get_hsr()`.
-
-Fixes:
-
- - Fix `mdbx_strerror()` for `MDBX_BUSY` error (no error description is returned).
- - Fix update internal meta-geo information in read-only mode (`EACCESS` or `EBADFD` error).
- - Fix `mdbx_page_get()` null-defer when DB corrupted (crash by `SIGSEGV`).
- - Fix `mdbx_env_open()` for re-opening after non-fatal errors (`mdbx_chk` unexpected failures).
- - Workaround for MSVC 19.27 `static_assert()` bug.
- - Doxygen descriptions and refinement.
- - Update Valgrind's suppressions.
- - Workaround to avoid infinite loop of 'nested' testcase on MIPS under QEMU.
- - Fix a lot of typos & spelling (Thanks to Josh Soref for PR).
- - Fix `getopt()` messages for Windows (Thanks to Andrey Sporaw for reporting).
- - Fix MSVC compiler version requirements (Thanks to Andrey Sporaw for reporting).
- - Workarounds for QEMU's bugs to run tests for cross-builded library under QEMU.
- - Now C++ compiler optional for building by CMake.
-
-
-## v0.9.0 2020-07-31 (not a release, but API changes)
-
-Added features:
-
- - [Online C API reference](https://erthink.github.io/libmdbx/) by Doxygen.
- - Separated enums for environment, sub-databases, transactions, copying and data-update flags.
-
-Deprecated functions and flags:
-
- - Usage of custom comparators and the `mdbx_dbi_open_ex()` are deprecated, since such databases couldn't be checked by the `mdbx_chk` utility.
-   Please use the value-to-key functions to provide keys that are compatible with the built-in libmdbx comparators.
-
-
-## v0.8.2 2020-07-06
-- Added support multi-opening the same DB in a process with SysV locking (BSD).
-- Fixed warnings & minors for LCC compiler (E2K).
-- Enabled to simultaneously open the same database from processes with and without the `MDBX_WRITEMAP` option.
-- Added key-to-value, `mdbx_get_keycmp()` and `mdbx_get_datacmp()` functions (helpful to avoid using custom comparators).
-- Added `ENABLE_UBSAN` CMake option to enabling the UndefinedBehaviorSanitizer from GCC/CLANG.
-- Workaround for [CLANG bug](https://bugs.llvm.org/show_bug.cgi?id=43275).
-- Returning `MDBX_CORRUPTED` in case all meta-pages are weak and no other error.
-- Refined mode bits while auto-creating LCK-file.
-- Avoids unnecessary database file re-mapping in case geometry changed by another process(es).
-  From the user's point of view, the `MDBX_UNABLE_EXTEND_MAPSIZE` error will now be returned less frequently and only when using the DB in the current process really requires it to be reopened.
-- Remapping on-the-fly and of the database file was implemented.
-  Now remapping with a change of address is performed automatically if there are no dependent readers in the current process.
-
-
-## v0.8.1 2020-06-12
-- Minor change versioning. The last number in the version now means the number of commits since last release/tag.
-- Provide ChangeLog file.
-- Fix for using libmdbx as a C-only sub-project with CMake.
-- Fix `mdbx_env_set_geometry()` for case it is called from an opened environment outside of a write transaction.
-- Add support for huge transactions and `MDBX_HUGE_TRANSACTIONS` build-option (default `OFF`).
-- Refine LTO (link time optimization) for clang.
-- Force enabling exceptions handling for MSVC (`/EHsc` option).
-
-
-## v0.8.0 2020-06-05
-- Support for Android/Bionic.
-- Support for iOS.
-- Auto-handling `MDBX_NOSUBDIR` while opening for any existing database.
-- Engage github-actions to make release-assets.
-- Clarify API description.
-- Extended keygen-cases in stochastic test.
-- Fix fetching of first/lower key from LEAF2-page during page merge.
-- Fix missing comma in array of error messages.
-- Fix div-by-zero while copy-with-compaction for non-resizable environments.
-- Fixes & enhancements for custom-comparators.
-- Fix `MDBX_AVOID_CRT` option and missing `ntdll.def`.
-- Fix `mdbx_env_close()` to work correctly called concurrently from several threads.
-- Fix null-deref in an ASAN-enabled builds while opening the environment with error and/or read-only.
-- Fix AddressSanitizer errors after closing the environment.
-- Fix/workaround to avoid GCC 10.x pedantic warnings.
-- Fix using `ENODATA` for FreeBSD.
-- Avoid invalidation of DBI-handle(s) when it just closes.
-- Avoid using `pwritev()` for single-writes (up to 10% speedup for some kernels & scenarios).
-- Avoiding `MDBX_UTTERLY_NOSYNC` as result of flags merge.
-- Add `mdbx_dbi_dupsort_depthmask()` function.
-- Add `MDBX_CP_FORCE_RESIZEABLE` option.
-- Add deprecated `MDBX_MAP_RESIZED` for compatibility.
-- Add `MDBX_BUILD_TOOLS` option (default `ON`).
-- Refine `mdbx_dbi_open_ex()` to safe concurrently opening the same handle from different threads.
-- Truncate clk-file during environment closing. So a zero-length lck-file indicates that the environment was closed properly.
-- Refine `mdbx_update_gc()` for huge transactions with small sizes of database page.
-- Extends dump/load to support all MDBX attributes.
-- Avoid upsertion the same key-value data, fix related assertions.
-- Rework min/max length checking for keys & values.
-- Checking the order of keys on all pages during checking.
-- Support `CFLAGS_EXTRA` make-option for convenience.
-- Preserve the last txnid while copying with compactification.
-- Auto-reset running transaction in mdbx_txn_renew().
-- Automatically abort errored transaction in mdbx_txn_commit().
-- Auto-choose page size for large databases.
-- Rearrange source files, rework build, options-support by CMake.
-- Crutch for WSL1 (Windows subsystem for Linux).
-- Refine install/uninstall targets.
-- Support for Valgrind 3.14 and later.
-- Add check-analyzer check-ubsan check-asan check-leak targets to Makefile.
-- Minor fix/workaround to avoid UBSAN traps for `memcpy(ptr, NULL, 0)`.
-- Avoid some GCC-analyzer false-positive warnings.
-
-
-## v0.7.0 2020-03-18
-- Workarounds for Wine (Windows compatibility layer for Linux).
-- `MDBX_MAP_RESIZED` renamed to `MDBX_UNABLE_EXTEND_MAPSIZE`.
-- Clarify API description, fix typos.
-- Speedup runtime checks in debug/checked builds.
-- Added checking for read/write transactions overlapping for the same thread, added `MDBX_TXN_OVERLAPPING` error and `MDBX_DBG_LEGACY_OVERLAP` option.
-- Added `mdbx_key_from_jsonInteger()`, `mdbx_key_from_double()`, `mdbx_key_from_float()`, `mdbx_key_from_int64()` and `mdbx_key_from_int32()` functions. See `mdbx.h` for description.
-- Fix compatibility (use zero for invalid DBI).
-- Refine/clarify error messages.
-- Avoids extra error messages "bad txn" from mdbx_chk when DB is corrupted.
-
-
-## v0.6.0 2020-01-21
-- Fix `mdbx_load` utility for custom comparators.
-- Fix checks related to `MDBX_APPEND` flag inside `mdbx_cursor_put()`.
-- Refine/fix dbi_bind() internals.
-- Refine/fix handling `STATUS_CONFLICTING_ADDRESSES`.
-- Rework `MDBX_DBG_DUMP` option to avoid disk I/O performance degradation.
-- Add built-in help to test tool.
-- Fix `mdbx_env_set_geometry()` for large page size.
-- Fix env_set_geometry() for large pagesize.
-- Clarify API description & comments, fix typos.
-
-
-## v0.5.0 2019-12-31
-- Fix returning MDBX_RESULT_TRUE from page_alloc().
-- Fix false-positive ASAN issue.
-- Fix assertion for `MDBX_NOTLS` option.
-- Rework `MADV_DONTNEED` threshold.
-- Fix `mdbx_chk` utility for don't checking some numbers if walking on the B-tree was disabled.
-- Use page's mp_txnid for basic integrity checking.
-- Add `MDBX_FORCE_ASSERTIONS` built-time option.
-- Rework `MDBX_DBG_DUMP` to avoid performance degradation.
-- Rename `MDBX_NOSYNC` to `MDBX_SAFE_NOSYNC` for clarity.
-- Interpret `ERROR_ACCESS_DENIED` from `OpenProcess()` as 'process exists'.
-- Avoid using `FILE_FLAG_NO_BUFFERING` for compatibility with small database pages.
-- Added install section for CMake.
-
-
-## v0.4.0 2019-12-02
-- Support for Mac OSX, FreeBSD, NetBSD, OpenBSD, DragonFly BSD, OpenSolaris, OpenIndiana (AIX and HP-UX pending).
-- Use bootid for decisions of rollback.
-- Counting retired pages and extended transaction info.
-- Add `MDBX_ACCEDE` flag for database opening.
-- Using OFD-locks and tracking for in-process multi-opening.
-- Hot backup into pipe.
-- Support for cmake & amalgamated sources.
-- Fastest internal sort implementation.
-- New internal dirty-list implementation with lazy sorting.
-- Support for lazy-sync-to-disk with polling.
-- Extended key length.
-- Last update transaction number for each sub-database.
-- Automatic read ahead enabling/disabling.
-- More auto-compactification.
-- Using -fsanitize=undefined and -Wpedantic options.
-- Rework page merging.
-- Nested transactions.
-- API description.
-- Checking for non-local filesystems to avoid DB corruption.
diff --git a/plugins/Dbx_mdbx/src/libmdbx/GNUmakefile b/plugins/Dbx_mdbx/src/libmdbx/GNUmakefile
deleted file mode 100644
index da781606ee..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/GNUmakefile
+++ /dev/null
@@ -1,182 +0,0 @@
-# This makefile is for GNU Make 3.80 or above, and nowadays provided
-# just for compatibility and preservation of traditions.
-#
-# Please use CMake in case of any difficulties or
-# problems with this old-school's magic.
-#
-################################################################################
-#
-# Preprocessor macros (for MDBX_OPTIONS) of interest.
-#
-# Note that the defaults should already be correct for most platforms;
-# you should not need to change any of these. Read their descriptions
-# in README and source code (see src/options.h) if you do.
-# There may be other macros of interest.
-#
-
-SHELL   := env bash
-
-# install sandbox
-DESTDIR ?=
-
-# install prefixes (inside sandbox)
-prefix  ?= /usr/local
-mandir  ?= $(prefix)/man
-
-# lib/bin suffix for multiarch/biarch, e.g. '.x86_64'
-suffix  ?=
-
-CC      ?= gcc
-CFLAGS_EXTRA ?=
-LD      ?= ld
-MDBX_OPTIONS ?= -DNDEBUG=1
-CFLAGS  ?= -O2 -g -Wall -Werror -Wextra -Wpedantic -ffunction-sections -fPIC -fvisibility=hidden -std=gnu11 -pthread -Wno-error=attributes $(CFLAGS_EXTRA)
-# -Wno-tautological-compare
-CXX     ?= g++
-# Choosing C++ standard with deferred simple variable expansion trick
-CXXSTD  ?= $(eval CXXSTD := $$(shell PROBE=$$$$([ -f mdbx.c++ ] && echo mdbx.c++ || echo src/mdbx.c++); for std in gnu++20 c++20 gnu++2a c++2a gnu++17 c++17 gnu++14 c++14 gnu+11 c++11; do $(CXX) -std=$$$${std} -c $$$${PROBE} -o /dev/null 2>/dev/null >/dev/null && echo "-std=$$$${std}" && exit; done))$(CXXSTD)
-CXXFLAGS = $(CXXSTD) $(filter-out -std=gnu11,$(CFLAGS))
-
-# HINT: Try append '--no-as-needed,-lrt' for ability to built with modern glibc, but then run with the old.
-LIBS    ?= $(shell uname | grep -qi SunOS && echo "-lkstat") $(shell uname | grep -qi -e Darwin -e OpenBSD || echo "-lrt") $(shell uname | grep -qi Windows && echo "-lntdll")
-
-LDFLAGS ?= $(shell $(LD) --help 2>/dev/null | grep -q -- --gc-sections && echo '-Wl,--gc-sections,-z,relro,-O1')$(shell $(LD) --help 2>/dev/null | grep -q -- -dead_strip && echo '-Wl,-dead_strip')
-EXE_LDFLAGS ?= -pthread
-
-################################################################################
-
-UNAME      := $(shell uname -s 2>/dev/null || echo Unknown)
-define uname2sosuffix
-  case "$(UNAME)" in
-    Darwin*|Mach*) echo dylib;;
-    CYGWIN*|MINGW*|MSYS*|Windows*) echo dll;;
-    *) echo so;;
-  esac
-endef
-SO_SUFFIX  := $(shell $(uname2sosuffix))
-
-HEADERS    := mdbx.h mdbx.h++
-LIBRARIES  := libmdbx.a libmdbx.$(SO_SUFFIX)
-TOOLS      := mdbx_stat mdbx_copy mdbx_dump mdbx_load mdbx_chk
-MANPAGES   := mdbx_stat.1 mdbx_copy.1 mdbx_dump.1 mdbx_load.1 mdbx_chk.1
-
-.PHONY: mdbx all install clean
-
-all: $(LIBRARIES) $(TOOLS)
-
-mdbx: libmdbx.a libmdbx.$(SO_SUFFIX)
-
-tools: $(TOOLS)
-
-strip: all
-	strip libmdbx.$(SO_SUFFIX) $(TOOLS)
-
-clean:
-	rm -rf $(TOOLS) mdbx_test @* *.[ao] *.[ls]o *.$(SO_SUFFIX) *.dSYM *~ tmp.db/* \
-		*.gcov *.log *.err src/*.o test/*.o mdbx_example dist \
-		config.h src/config.h src/version.c *.tar*
-
-libmdbx.a: mdbx-static.o mdbx++-static.o
-	$(AR) rs $@ $?
-
-libmdbx.$(SO_SUFFIX): mdbx-dylib.o mdbx++-dylib.o
-	$(CXX) $(CXXFLAGS) $^ -pthread -shared $(LDFLAGS) $(LIBS) -o $@
-
-
-################################################################################
-# Amalgamated source code, i.e. distributed after `make dist`
-MAN_SRCDIR := man1/
-
-config.h: mdbx.c $(lastword $(MAKEFILE_LIST))
-	(echo '#define MDBX_BUILD_TIMESTAMP "$(shell date +%Y-%m-%dT%H:%M:%S%z)"' \
-	&& echo '#define MDBX_BUILD_FLAGS "$(CXXSTD) $(CFLAGS) $(LDFLAGS) $(LIBS)"' \
-	&& echo '#define MDBX_BUILD_COMPILER "$(shell (LC_ALL=C $(CC) --version || echo 'Please use GCC or CLANG compatible compiler') | head -1)"' \
-	&& echo '#define MDBX_BUILD_TARGET "$(shell set -o pipefail; (LC_ALL=C $(CC) -v 2>&1 | grep -i '^Target:' | cut -d ' ' -f 2- || (LC_ALL=C $(CC) --version | grep -qi e2k && echo E2K) || echo 'Please use GCC or CLANG compatible compiler') | head -1)"' \
-	) > $@
-
-mdbx-dylib.o: config.h mdbx.c mdbx.h $(lastword $(MAKEFILE_LIST))
-	$(CC) $(CFLAGS) $(MDBX_OPTIONS) '-DMDBX_CONFIG_H="config.h"' -DLIBMDBX_EXPORTS=1 -c mdbx.c -o $@
-
-mdbx-static.o: config.h mdbx.c mdbx.h $(lastword $(MAKEFILE_LIST))
-	$(CC) $(CFLAGS) $(MDBX_OPTIONS) '-DMDBX_CONFIG_H="config.h"' -ULIBMDBX_EXPORTS -c mdbx.c -o $@
-
-mdbx++-dylib.o: config.h mdbx.c++ mdbx.h mdbx.h++ $(lastword $(MAKEFILE_LIST))
-	$(CXX) $(CXXFLAGS) $(MDBX_OPTIONS) '-DMDBX_CONFIG_H="config.h"' -DLIBMDBX_EXPORTS=1 -c mdbx.c++ -o $@
-
-mdbx++-static.o: config.h mdbx.c++ mdbx.h mdbx.h++ $(lastword $(MAKEFILE_LIST))
-	$(CXX) $(CXXFLAGS) $(MDBX_OPTIONS) '-DMDBX_CONFIG_H="config.h"' -ULIBMDBX_EXPORTS -c mdbx.c++ -o $@
-
-mdbx_%:	mdbx_%.c libmdbx.a
-	$(CC) $(CFLAGS) $(MDBX_OPTIONS) '-DMDBX_CONFIG_H="config.h"' $^ $(EXE_LDFLAGS) $(LIBS) -o $@
-
-install: $(LIBRARIES) $(TOOLS) $(HEADERS)
-	install -D -p -s -t $(DESTDIR)$(prefix)/bin$(suffix) $(TOOLS) && \
-	install -D -p -s -t $(DESTDIR)$(prefix)/lib$(suffix) $(filter-out libmdbx.a,$(LIBRARIES)) && \
-	install -D -p -t $(DESTDIR)$(prefix)/lib$(suffix) libmdbx.a && \
-	install -D -p -m 444 -t $(DESTDIR)$(prefix)/include $(HEADERS) && \
-	install -D -p -m 444 -t $(DESTDIR)$(mandir)/man1 $(addprefix $(MAN_SRCDIR), $(MANPAGES))
-
-uninstall:
-	rm -f $(addprefix $(DESTDIR)$(prefix)/bin$(suffix)/,$(TOOLS)) \
-		$(addprefix $(DESTDIR)$(prefix)/lib$(suffix)/,$(LIBRARIES)) \
-		$(addprefix $(DESTDIR)$(prefix)/include/,$(HEADERS)) \
-		$(addprefix $(DESTDIR)$(mandir)/man1/,$(MANPAGES))
-
-################################################################################
-# Benchmarking by ioarena
-
-IOARENA ?= $(shell \
-  (test -x ../ioarena/@BUILD/src/ioarena && echo ../ioarena/@BUILD/src/ioarena) || \
-  (test -x ../../@BUILD/src/ioarena && echo ../../@BUILD/src/ioarena) || \
-  (test -x ../../src/ioarena && echo ../../src/ioarena) || which ioarena)
-NN	?= 25000000
-BENCH_CRUD_MODE ?= nosync
-
-ifneq ($(wildcard $(IOARENA)),)
-
-.PHONY: bench clean-bench re-bench
-
-clean-bench:
-	rm -rf bench-*.txt _ioarena/*
-
-re-bench: clean-bench bench
-
-define bench-rule
-bench-$(1)_$(2).txt: $(3) $(IOARENA) $(lastword $(MAKEFILE_LIST))
-	LD_LIBRARY_PATH="./:$$$${LD_LIBRARY_PATH}" \
-		$(IOARENA) -D $(1) -B crud -m $(BENCH_CRUD_MODE) -n $(2) \
-		| tee $$@ | grep throughput && \
-	LD_LIBRARY_PATH="./:$$$${LD_LIBRARY_PATH}" \
-		$(IOARENA) -D $(1) -B get,iterate -m $(BENCH_CRUD_MODE) -r 4 -n $(2) \
-		| tee -a $$@ | grep throughput \
-	|| mv -f $$@ $$@.error
-
-endef
-
-$(eval $(call bench-rule,mdbx,$(NN),libmdbx.$(SO_SUFFIX)))
-
-$(eval $(call bench-rule,sophia,$(NN)))
-$(eval $(call bench-rule,leveldb,$(NN)))
-$(eval $(call bench-rule,rocksdb,$(NN)))
-$(eval $(call bench-rule,wiredtiger,$(NN)))
-$(eval $(call bench-rule,forestdb,$(NN)))
-$(eval $(call bench-rule,lmdb,$(NN)))
-$(eval $(call bench-rule,nessdb,$(NN)))
-$(eval $(call bench-rule,sqlite3,$(NN)))
-$(eval $(call bench-rule,ejdb,$(NN)))
-$(eval $(call bench-rule,vedisdb,$(NN)))
-$(eval $(call bench-rule,dummy,$(NN)))
-
-$(eval $(call bench-rule,debug,10))
-
-bench: bench-mdbx_$(NN).txt
-
-.PHONY: bench-debug
-
-bench-debug: bench-debug_10.txt
-
-bench-quartet: bench-mdbx_$(NN).txt bench-lmdb_$(NN).txt bench-rocksdb_$(NN).txt bench-wiredtiger_$(NN).txt
-bench-triplet: bench-mdbx_$(NN).txt bench-lmdb_$(NN).txt bench-sqlite3_$(NN).txt
-bench-couple: bench-mdbx_$(NN).txt bench-lmdb_$(NN).txt
-
-endif
diff --git a/plugins/Dbx_mdbx/src/libmdbx/LICENSE b/plugins/Dbx_mdbx/src/libmdbx/LICENSE
deleted file mode 100644
index 05ad7571e4..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/LICENSE
+++ /dev/null
@@ -1,47 +0,0 @@
-The OpenLDAP Public License
-  Version 2.8, 17 August 2003
-
-Redistribution and use of this software and associated documentation
-("Software"), with or without modification, are permitted provided
-that the following conditions are met:
-
-1. Redistributions in source form must retain copyright statements
-   and notices,
-
-2. Redistributions in binary form must reproduce applicable copyright
-   statements and notices, this list of conditions, and the following
-   disclaimer in the documentation and/or other materials provided
-   with the distribution, and
-
-3. Redistributions must contain a verbatim copy of this document.
-
-The OpenLDAP Foundation may revise this license from time to time.
-Each revision is distinguished by a version number.  You may use
-this Software under terms of this license revision or under the
-terms of any subsequent revision of the license.
-
-THIS SOFTWARE IS PROVIDED BY THE OPENLDAP FOUNDATION AND ITS
-CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
-INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
-AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT
-SHALL THE OPENLDAP FOUNDATION, ITS CONTRIBUTORS, OR THE AUTHOR(S)
-OR OWNER(S) OF THE SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
-INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
-CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
-ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-
-The names of the authors and copyright holders must not be used in
-advertising or otherwise to promote the sale, use or other dealing
-in this Software without specific, written prior permission.  Title
-to copyright in this Software shall at all times remain with copyright
-holders.
-
-OpenLDAP is a registered trademark of the OpenLDAP Foundation.
-
-Copyright 1999-2003 The OpenLDAP Foundation, Redwood City,
-California, USA.  All Rights Reserved.  Permission to copy and
-distribute verbatim copies of this document is granted.
diff --git a/plugins/Dbx_mdbx/src/libmdbx/Makefile b/plugins/Dbx_mdbx/src/libmdbx/Makefile
deleted file mode 100644
index bb4aa0531f..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/Makefile
+++ /dev/null
@@ -1,7 +0,0 @@
-# This is thunk-Makefile for calling GNU Make 3.80 or above
-
-all bench bench-quartet build-test check clean clean-bench cross-gcc cross-qemu dist doxygen gcc-analyzer install mdbx memcheck reformat release-assets strip test test-asan test-fault test-leak test-singleprocess test-ubsan test-valgrind tools:
-	@CC=$(CC) \
-	CXX=`if test -n "$(CXX)" && which "$(CXX)" > /dev/null; then echo "$(CXX)"; elif test -n "$(CCC)" && which "$(CCC)" > /dev/null; then echo "$(CCC)"; else echo "c++"; fi` \
-	`which gmake || which gnumake || echo 'echo "GNU Make 3.80 or above is required"; exit 2;'` \
-		$(MAKEFLAGS) -f GNUmakefile $@
diff --git a/plugins/Dbx_mdbx/src/libmdbx/README.md b/plugins/Dbx_mdbx/src/libmdbx/README.md
deleted file mode 100644
index 66da37c454..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/README.md
+++ /dev/null
@@ -1,638 +0,0 @@
-<!-- Required extensions: pymdownx.betterem, pymdownx.tilde, pymdownx.emoji, pymdownx.tasklist, pymdownx.superfences -->
-
-> Please refer to the online [documentation](https://erthink.github.io/libmdbx/)
-> with [`C` API description](https://erthink.github.io/libmdbx/group__c__api.html)
-> and pay attention to the preliminary [`C++` API](https://github.com/erthink/libmdbx/blob/devel/mdbx.h%2B%2B).
->
-> Questions, feedback and suggestions are welcome to the [Telegram' group](https://t.me/libmdbx).
->
-> For NEWS take a look to the [ChangeLog](./ChangeLog.md).
-
-libmdbx
-========
-
-<!-- section-begin overview -->
-_libmdbx_ is an extremely fast, compact, powerful, embedded,
-transactional [key-value database](https://en.wikipedia.org/wiki/Key-value_database),
-with [permissive license](./LICENSE).
-_libmdbx_ has a specific set of properties and capabilities,
-focused on creating unique lightweight solutions.
-
-1. Allows **a swarm of multi-threaded processes to
-[ACID]((https://en.wikipedia.org/wiki/ACID))ly read and update** several
-key-value [maps](https://en.wikipedia.org/wiki/Associative_array) and
-[multimaps](https://en.wikipedia.org/wiki/Multimap) in a locally-shared
-database.
-
-2. Provides **extraordinary performance**, minimal overhead through
-[Memory-Mapping](https://en.wikipedia.org/wiki/Memory-mapped_file) and
-`Olog(N)` operations costs by virtue of [B+
-tree](https://en.wikipedia.org/wiki/B%2B_tree).
-
-3. Requires **no maintenance and no crash recovery** since it doesn't use
-[WAL](https://en.wikipedia.org/wiki/Write-ahead_logging), but that might
-be a caveat for write-intensive workloads with durability requirements.
-
-4. **Compact and friendly for fully embedding**. Only ≈25KLOC of `C11`,
-≈64K x86 binary code of core, no internal threads neither server process(es),
-but implements a simplified variant of the [Berkeley
-DB](https://en.wikipedia.org/wiki/Berkeley_DB) and
-[dbm](https://en.wikipedia.org/wiki/DBM_(computing)) API.
-
-5. Enforces [serializability](https://en.wikipedia.org/wiki/Serializability) for
-writers just by single
-[mutex](https://en.wikipedia.org/wiki/Mutual_exclusion) and affords
-[wait-free](https://en.wikipedia.org/wiki/Non-blocking_algorithm#Wait-freedom)
-for parallel readers without atomic/interlocked operations, while
-**writing and reading transactions do not block each other**.
-
-6. **Guarantee data integrity** after crash unless this was explicitly
-neglected in favour of write performance.
-
-7. Supports Linux, Windows, MacOS, Android, iOS, FreeBSD, DragonFly, Solaris,
-OpenSolaris, OpenIndiana, NetBSD, OpenBSD and other systems compliant with
-**POSIX.1-2008**.
-<!-- section-end -->
-
-Historically, _libmdbx_ is a deeply revised and extended descendant of the amazing
-[Lightning Memory-Mapped Database](https://en.wikipedia.org/wiki/Lightning_Memory-Mapped_Database).
-_libmdbx_ inherits all benefits from _LMDB_, but resolves some issues and adds [a set of improvements](#improvements-beyond-lmdb).
-
-<!-- section-begin mithril -->
-The next version is under active non-public development from scratch and will be
-released as _**MithrilDB**_ and `libmithrildb` for libraries & packages.
-Admittedly mythical [Mithril](https://en.wikipedia.org/wiki/Mithril) is
-resembling silver but being stronger and lighter than steel. Therefore
-_MithrilDB_ is a rightly relevant name.
-  > _MithrilDB_ will be radically different from _libmdbx_ by the new
-  > database format and API based on C++17, as well as the [Apache 2.0
-  > License](https://www.apache.org/licenses/LICENSE-2.0). The goal of this
-  > revolution is to provide a clearer and robust API, add more features and
-  > new valuable properties of the database.
-<!-- section-end -->
-
-[![https://t.me/libmdbx](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/telegram.png)](https://t.me/libmdbx)
-[![GithubCI](https://github.com/erthink/libmdbx/workflows/CI/badge.svg)](https://github.com/erthink/libmdbx/actions?query=workflow%3ACI)
-[![TravisCI](https://travis-ci.org/erthink/libmdbx.svg?branch=master)](https://travis-ci.org/erthink/libmdbx)
-[![AppveyorCI](https://ci.appveyor.com/api/projects/status/ue94mlopn50dqiqg/branch/master?svg=true)](https://ci.appveyor.com/project/leo-yuriev/libmdbx/branch/master)
-[![CircleCI](https://circleci.com/gh/erthink/libmdbx/tree/master.svg?style=svg)](https://circleci.com/gh/erthink/libmdbx/tree/master)
-[![CirrusCI](https://api.cirrus-ci.com/github/erthink/libmdbx.svg)](https://cirrus-ci.com/github/erthink/libmdbx)
-[![Coverity Scan Status](https://scan.coverity.com/projects/12915/badge.svg)](https://scan.coverity.com/projects/reopen-libmdbx)
-
-*The Future will (be) [Positive](https://www.ptsecurity.com). Всё будет хорошо.*
-
------
-
-## Table of Contents
-- [Characteristics](#characteristics)
-    - [Features](#features)
-    - [Limitations](#limitations)
-    - [Gotchas](#gotchas)
-    - [Comparison with other databases](#comparison-with-other-databases)
-    - [Improvements beyond LMDB](#improvements-beyond-lmdb)
-    - [History & Acknowledgments](#history)
-- [Usage](#usage)
-    - [Building](#building)
-    - [API description](#api-description)
-    - [Bindings](#bindings)
-- [Performance comparison](#performance-comparison)
-    - [Integral performance](#integral-performance)
-    - [Read scalability](#read-scalability)
-    - [Sync-write mode](#sync-write-mode)
-    - [Lazy-write mode](#lazy-write-mode)
-    - [Async-write mode](#async-write-mode)
-    - [Cost comparison](#cost-comparison)
-
-# Characteristics
-
-<!-- section-begin characteristics -->
-
-## Features
-
-- Key-value data model, keys are always sorted.
-
-- Fully [ACID](https://en.wikipedia.org/wiki/ACID)-compliant, through to
-[MVCC](https://en.wikipedia.org/wiki/Multiversion_concurrency_control)
-and [CoW](https://en.wikipedia.org/wiki/Copy-on-write).
-
-- Multiple key-value sub-databases within a single datafile.
-
-- Range lookups, including range query estimation.
-
-- Efficient support for short fixed length keys, including native 32/64-bit integers.
-
-- Ultra-efficient support for [multimaps](https://en.wikipedia.org/wiki/Multimap). Multi-values sorted, searchable and iterable. Keys stored without duplication.
-
-- Data is [memory-mapped](https://en.wikipedia.org/wiki/Memory-mapped_file) and accessible directly/zero-copy. Traversal of database records is extremely-fast.
-
-- Transactions for readers and writers, ones do not block others.
-
-- Writes are strongly serialized. No transaction conflicts nor deadlocks.
-
-- Readers are [non-blocking](https://en.wikipedia.org/wiki/Non-blocking_algorithm), notwithstanding [snapshot isolation](https://en.wikipedia.org/wiki/Snapshot_isolation).
-
-- Nested write transactions.
-
-- Reads scale linearly across CPUs.
-
-- Continuous zero-overhead database compactification.
-
-- Automatic on-the-fly database size adjustment.
-
-- Customizable database page size.
-
-- `Olog(N)` cost of lookup, insert, update, and delete operations by virtue of [B+ tree characteristics](https://en.wikipedia.org/wiki/B%2B_tree#Characteristics).
-
-- Online hot backup.
-
-- Append operation for efficient bulk insertion of pre-sorted data.
-
-- No [WAL](https://en.wikipedia.org/wiki/Write-ahead_logging) nor any
-transaction journal. No crash recovery needed. No maintenance is required.
-
-- No internal cache and/or memory management, all done by basic OS services.
-
-## Limitations
-
-- **Page size**: a power of 2, maximum `65536` bytes, default `4096` bytes.
-- **Key size**: minimum 0, maximum ≈¼ pagesize (`1300` bytes for default 4K pagesize, `21780` bytes for 64K pagesize).
-- **Value size**: minimum 0, maximum `2146435072` (`0x7FF00000`) bytes for maps, ≈¼ pagesize for multimaps (`1348` bytes for default 4K pagesize, `21828` bytes for 64K pagesize).
-- **Write transaction size**: up to `4194301` (`0x3FFFFD`) pages (16 [GiB](https://en.wikipedia.org/wiki/Gibibyte) for default 4K pagesize, 256 [GiB](https://en.wikipedia.org/wiki/Gibibyte) for 64K pagesize).
-- **Database size**: up to `2147483648` pages (8 [TiB](https://en.wikipedia.org/wiki/Tebibyte) for default 4K pagesize, 128 [TiB](https://en.wikipedia.org/wiki/Tebibyte) for 64K pagesize).
-- **Maximum sub-databases**: `32765`.
-
-## Gotchas
-
-1. There cannot be more than one writer at a time, i.e. no more than one write transaction at a time.
-
-2. _libmdbx_ is based on [B+ tree](https://en.wikipedia.org/wiki/B%2B_tree), so access to database pages is mostly random.
-Thus SSDs provide a significant performance boost over spinning disks for large databases.
-
-3. _libmdbx_ uses [shadow paging](https://en.wikipedia.org/wiki/Shadow_paging) instead of [WAL](https://en.wikipedia.org/wiki/Write-ahead_logging). Thus syncing data to disk might be a bottleneck for write intensive workload.
-
-4. _libmdbx_ uses [copy-on-write](https://en.wikipedia.org/wiki/Copy-on-write) for [snapshot isolation](https://en.wikipedia.org/wiki/Snapshot_isolation) during updates, but read transactions prevents recycling an old retired/freed pages, since it read ones. Thus altering of data during a parallel
-long-lived read operation will increase the process work set, may exhaust entire free database space,
-the database can grow quickly, and result in performance degradation.
-Try to avoid long running read transactions.
-
-5. _libmdbx_ is extraordinarily fast and provides minimal overhead for data access,
-so you should reconsider using brute force techniques and double check your code.
-On the one hand, in the case of _libmdbx_, a simple linear search may be more profitable than complex indexes.
-On the other hand, if you make something suboptimally, you can notice detrimentally only on sufficiently large data.
-
-## Comparison with other databases
-For now please refer to [chapter of "BoltDB comparison with other
-databases"](https://github.com/coreos/bbolt#comparison-with-other-databases)
-which is also (mostly) applicable to _libmdbx_.
-
-<!-- section-end -->
-<!-- section-begin improvements -->
-
-Improvements beyond LMDB
-========================
-
-_libmdbx_ is superior to legendary _[LMDB](https://symas.com/lmdb/)_ in
-terms of features and reliability, not inferior in performance. In
-comparison to _LMDB_, _libmdbx_ make things "just work" perfectly and
-out-of-the-box, not silently and catastrophically break down. The list
-below is pruned down to the improvements most notable and obvious from
-the user's point of view.
-
-## Added Features
-
-1. Keys could be more than 2 times longer than _LMDB_.
-  > For DB with default page size _libmdbx_ support keys up to 1300 bytes
-  > and up to 21780 bytes for 64K page size. _LMDB_ allows key size up to
-  > 511 bytes and may silently loses data with large values.
-
-2. Up to 20% faster than _LMDB_ in [CRUD](https://en.wikipedia.org/wiki/Create,_read,_update_and_delete) benchmarks.
-  > Benchmarks of the in-[tmpfs](https://en.wikipedia.org/wiki/Tmpfs) scenarios,
-  > that tests the speed of the engine itself, showned that _libmdbx_ 10-20% faster than _LMDB_.
-  > These and other results could be easily reproduced with [ioArena](https://github.com/pmwkaa/ioarena) just by `make bench-quartet` command,
-  > including comparisons with [RockDB](https://en.wikipedia.org/wiki/RocksDB)
-  > and [WiredTiger](https://en.wikipedia.org/wiki/WiredTiger).
-
-3. Automatic on-the-fly database size adjustment, both increment and reduction.
-  > _libmdbx_ manages the database size according to parameters specified
-  > by `mdbx_env_set_geometry()` function,
-  > ones include the growth step and the truncation threshold.
-  >
-  > Unfortunately, on-the-fly database size adjustment doesn't work under [Wine](https://en.wikipedia.org/wiki/Wine_(software))
-  > due to its internal limitations and unimplemented functions, i.e. the `MDBX_UNABLE_EXTEND_MAPSIZE` error will be returned.
-
-4. Automatic continuous zero-overhead database compactification.
-  > During each commit _libmdbx_ merges suitable freeing pages into unallocated area
-  > at the end of file, and then truncates unused space when a lot enough of.
-
-5. The same database format for 32- and 64-bit builds.
-  > _libmdbx_ database format depends only on the [endianness](https://en.wikipedia.org/wiki/Endianness) but not on the [bitness](https://en.wiktionary.org/wiki/bitness).
-
-6. LIFO policy for Garbage Collection recycling. This can significantly increase write performance due write-back disk cache up to several times in a best case scenario.
-  > LIFO means that for reuse will be taken the latest becomes unused pages.
-  > Therefore the loop of database pages circulation becomes as short as possible.
-  > In other words, the set of pages, that are (over)written in memory and on disk during a series of write transactions, will be as small as possible.
-  > Thus creates ideal conditions for the battery-backed or flash-backed disk cache efficiency.
-
-7. Fast estimation of range query result volume, i.e. how many items can
-be found between a `KEY1` and a `KEY2`. This is a prerequisite for build
-and/or optimize query execution plans.
-  > _libmdbx_ performs a rough estimate based on common B-tree pages of the paths from root to corresponding keys.
-
-8. `mdbx_chk` utility for database integrity check.
-Since version 0.9.1, the utility supports checking the database using any of the three meta pages and the ability to switch to it.
-
-9. Automated steady sync-to-disk upon several thresholds and/or timeout via cheap polling.
-
-10. Sequence generation and three persistent 64-bit markers.
-
-11. Handle-Slow-Readers callback to resolve a database full/overflow issues due to long-lived read transaction(s).
-
-12. Support for opening databases in the exclusive mode, including on a network share.
-
-## Added Abilities
-
-1. Zero-length for keys and values.
-
-2. Ability to determine whether the particular data is on a dirty page
-or not, that allows to avoid copy-out before updates.
-
-3. Ability to determine whether the cursor is pointed to a key-value
-pair, to the first, to the last, or not set to anything.
-
-4. Extended information of whole-database, sub-databases, transactions, readers enumeration.
-  > _libmdbx_ provides a lot of information, including dirty and leftover pages
-  > for a write transaction, reading lag and holdover space for read transactions.
-
-5. Extended update and delete operations.
-  > _libmdbx_ allows one _at once_ with getting previous value
-  > and addressing the particular item from multi-value with the same key.
-
-## Other fixes and specifics
-
-1. Fixed more than 10 significant errors, in particular: page leaks,
-wrong sub-database statistics, segfault in several conditions,
-nonoptimal page merge strategy, updating an existing record with
-a change in data size (including for multimap), etc.
-
-2. All cursors can be reused and should be closed explicitly,
-regardless ones were opened within a write or read transaction.
-
-3. Opening database handles are spared from race conditions and
-pre-opening is not needed.
-
-4. Returning `MDBX_EMULTIVAL` error in case of ambiguous update or delete.
-
-5. Guarantee of database integrity even in asynchronous unordered write-to-disk mode.
-  > _libmdbx_ propose additional trade-off by `MDBX_SAFE_NOSYNC` with append-like manner for updates,
-  > that avoids database corruption after a system crash contrary to LMDB.
-  > Nevertheless, the `MDBX_UTTERLY_NOSYNC` mode is available to match behaviour of the `MDB_NOSYNC` in LMDB.
-
-6. On **MacOS & iOS** the `fcntl(F_FULLFSYNC)` syscall is used _by
-default_ to synchronize data with the disk, as this is [the only way to
-guarantee data
-durability](https://developer.apple.com/library/archive/documentation/System/Conceptual/ManPages_iPhoneOS/man2/fsync.2.html)
-in case of power failure. Unfortunately, in scenarios with high write
-intensity, the use of `F_FULLFSYNC` significantly degrades performance
-compared to LMDB, where the `fsync()` syscall is used. Therefore,
-_libmdbx_ allows you to override this behavior by defining the
-`MDBX_OSX_SPEED_INSTEADOF_DURABILITY=1` option while build the library.
-
-7. On **Windows** the `LockFileEx()` syscall is used for locking, since
-it allows place the database on network drives, and provides protection
-against incompetent user actions (aka
-[poka-yoke](https://en.wikipedia.org/wiki/Poka-yoke)). Therefore
-_libmdbx_ may be a little lag in performance tests from LMDB where the
-named mutexes are used.
-
-<!-- section-end -->
-<!-- section-begin history -->
-
-# History
-
-Historically, _libmdbx_ is a deeply revised and extended descendant of the
-[Lightning Memory-Mapped Database](https://en.wikipedia.org/wiki/Lightning_Memory-Mapped_Database).
-At first the development was carried out within the
-[ReOpenLDAP](https://github.com/erthink/ReOpenLDAP) project. About a
-year later _libmdbx_ was separated into a standalone project, which was
-[presented at Highload++ 2015
-conference](http://www.highload.ru/2015/abstracts/1831.html).
-
-Since 2017 _libmdbx_ is used in [Fast Positive Tables](https://github.com/erthink/libfpta),
-and development is funded by [Positive Technologies](https://www.ptsecurity.com).
-
-## Acknowledgments
-Howard Chu <hyc@openldap.org> is the author of LMDB, from which
-originated the _libmdbx_ in 2015.
-
-Martin Hedenfalk <martin@bzero.se> is the author of `btree.c` code, which
-was used to begin development of LMDB.
-
-<!-- section-end -->
-
---------------------------------------------------------------------------------
-
-Usage
-=====
-
-<!-- section-begin usage -->
-Currently, libmdbx is only available in a
-[source code](https://en.wikipedia.org/wiki/Source_code) form.
-Packages support for common Linux distributions is planned in the future,
-since release the version 1.0.
-
-## Source code embedding
-
-_libmdbx_ provides two official ways for integration in source code form:
-
-1. Using the amalgamated source code.
-  > The amalgamated source code includes all files required to build and
-  > use _libmdbx_, but not for testing _libmdbx_ itself.
-
-2. Adding the complete original source code as a `git submodule`.
-  > This allows you to build as _libmdbx_ and testing tool.
-  >  On the other hand, this way requires you to pull git tags, and use C++11 compiler for test tool.
-
-_**Please, avoid using any other techniques.**_ Otherwise, at least
-don't ask for support and don't name such chimeras `libmdbx`.
-
-The amalgamated source code could be created from the original clone of git
-repository on Linux by executing `make dist`. As a result, the desired
-set of files will be formed in the `dist` subdirectory.
-
-## Building
-
-Both amalgamated and original source code provides build through the use
-[CMake](https://cmake.org/) or [GNU
-Make](https://www.gnu.org/software/make/) with
-[bash](https://en.wikipedia.org/wiki/Bash_(Unix_shell)). All build ways
-are completely traditional and have minimal prerequirements like
-`build-essential`, i.e. the non-obsolete C/C++ compiler and a
-[SDK](https://en.wikipedia.org/wiki/Software_development_kit) for the
-target platform. Obviously you need building tools itself, i.e. `git`,
-`cmake` or GNU `make` with `bash`.
-
-So just using CMake or GNU Make in your habitual manner and feel free to
-fill an issue or make pull request in the case something will be
-unexpected or broken down.
-
-#### DSO/DLL unloading and destructors of Thread-Local-Storage objects
-When building _libmdbx_ as a shared library or use static _libmdbx_ as a
-part of another dynamic library, it is advisable to make sure that your
-system ensures the correctness of the call destructors of
-Thread-Local-Storage objects when unloading dynamic libraries.
-
-If this is not the case, then unloading a dynamic-link library with
-_libmdbx_ code inside, can result in either a resource leak or a crash
-due to calling destructors from an already unloaded DSO/DLL object. The
-problem can only manifest in a multithreaded application, which makes
-the unloading of shared dynamic libraries with _libmdbx_ code inside,
-after using _libmdbx_. It is known that TLS-destructors are properly
-maintained in the following cases:
-
-- On all modern versions of Windows (Windows 7 and later).
-
-- On systems with the
-[`__cxa_thread_atexit_impl()`](https://sourceware.org/glibc/wiki/Destructor%20support%20for%20thread_local%20variables)
-function in the standard C library, including systems with GNU libc
-version 2.18 and later.
-
-- On systems with libpthread/ntpl from GNU libc with bug fixes
-[#21031](https://sourceware.org/bugzilla/show_bug.cgi?id=21031) and
-[#21032](https://sourceware.org/bugzilla/show_bug.cgi?id=21032), or
-where there are no similar bugs in the pthreads implementation.
-
-### Linux and other platforms with GNU Make
-To build the library it is enough to execute `make all` in the directory
-of source code, and `make check` to execute the basic tests.
-
-If the `make` installed on the system is not GNU Make, there will be a
-lot of errors from make when trying to build. In this case, perhaps you
-should use `gmake` instead of `make`, or even `gnu-make`, etc.
-
-### FreeBSD and related platforms
-As a rule, in such systems, the default is to use Berkeley Make. And GNU
-Make is called by the gmake command or may be missing. In addition,
-[bash](https://en.wikipedia.org/wiki/Bash_(Unix_shell)) may be absent.
-
-You need to install the required components: GNU Make, bash, C and C++
-compilers compatible with GCC or CLANG. After that, to build the
-library, it is enough to execute `gmake all` (or `make all`) in the
-directory with source code, and `gmake check` (or `make check`) to run
-the basic tests.
-
-### Windows
-For build _libmdbx_ on Windows the _original_ CMake and [Microsoft Visual
-Studio 2019](https://en.wikipedia.org/wiki/Microsoft_Visual_Studio) are
-recommended. Otherwise do not forget to add `ntdll.lib` to linking.
-
-Building by MinGW, MSYS or Cygwin is potentially possible. However,
-these scripts are not tested and will probably require you to modify the
-CMakeLists.txt or Makefile respectively.
-
-It should be noted that in _libmdbx_ was efforts to resolve
-runtime dependencies from CRT and other libraries Visual Studio.
-For this is enough to define the `MDBX_AVOID_CRT` during build.
-
-An example of running a basic test script can be found in the
-[CI-script](appveyor.yml) for [AppVeyor](https://www.appveyor.com/). To
-run the [long stochastic test scenario](test/long_stochastic.sh),
-[bash](https://en.wikipedia.org/wiki/Bash_(Unix_shell)) is required, and
-such testing is recommended with placing the test data on the
-[RAM-disk](https://en.wikipedia.org/wiki/RAM_drive).
-
-### Windows Subsystem for Linux
-_libmdbx_ could be used in [WSL2](https://en.wikipedia.org/wiki/Windows_Subsystem_for_Linux#WSL_2)
-but NOT in [WSL1](https://en.wikipedia.org/wiki/Windows_Subsystem_for_Linux#WSL_1) environment.
-This is a consequence of the fundamental shortcomings of _WSL1_ and cannot be fixed.
-To avoid data loss, _libmdbx_ returns the `ENOLCK` (37, "No record locks available")
-error when opening the database in a _WSL1_ environment.
-
-### MacOS
-Current [native build tools](https://en.wikipedia.org/wiki/Xcode) for
-MacOS include GNU Make, CLANG and an outdated version of bash.
-Therefore, to build the library, it is enough to run `make all` in the
-directory with source code, and run `make check` to execute the base
-tests. If something goes wrong, it is recommended to install
-[Homebrew](https://brew.sh/) and try again.
-
-To run the [long stochastic test scenario](test/long_stochastic.sh), you
-will need to install the current (not outdated) version of
-[bash](https://en.wikipedia.org/wiki/Bash_(Unix_shell)). To do this, we
-recommend that you install [Homebrew](https://brew.sh/) and then execute
-`brew install bash`.
-
-### Android
-We recommend using CMake to build _libmdbx_ for Android.
-Please refer to the [official guide](https://developer.android.com/studio/projects/add-native-code).
-
-### iOS
-To build _libmdbx_ for iOS, we recommend using CMake with the
-"[toolchain file](https://cmake.org/cmake/help/latest/variable/CMAKE_TOOLCHAIN_FILE.html)"
-from the [ios-cmake](https://github.com/leetal/ios-cmake) project.
-
-<!-- section-end -->
-
-## API description
-
-Please refer to the online [_libmdbx_ API reference](https://erthink.github.io/libmdbx/)
-and/or see the [mdbx.h](mdbx.h) header.
-
-<!-- section-begin bindings -->
-
-Bindings
-========
-
-| Runtime | GitHub | Author |
-| ------- | ------ | ------ |
-| [Nim](https://en.wikipedia.org/wiki/Nim_(programming_language)) | [NimDBX](https://github.com/snej/nimdbx) | [Jens Alfke](https://github.com/snej)
-| Rust    | [heed](https://github.com/Kerollmops/heed), [mdbx-rs](https://github.com/Kerollmops/mdbx-rs)   | [Clément Renault](https://github.com/Kerollmops) |
-| Java    | [mdbxjni](https://github.com/castortech/mdbxjni)   | [Castor Technologies](https://castortech.com/) |
-| .NET    | [mdbx.NET](https://github.com/wangjia184/mdbx.NET) | [Jerry Wang](https://github.com/wangjia184) |
-
-<!-- section-end -->
-
---------------------------------------------------------------------------------
-
-<!-- section-begin performance -->
-
-Performance comparison
-======================
-
-All benchmarks were done in 2015 by [IOArena](https://github.com/pmwkaa/ioarena)
-and multiple [scripts](https://github.com/pmwkaa/ioarena/tree/HL%2B%2B2015)
-runs on Lenovo Carbon-2 laptop, i7-4600U 2.1 GHz (2 physical cores, 4 HyperThreading cores), 8 Gb RAM,
-SSD SAMSUNG MZNTD512HAGL-000L1 (DXT23L0Q) 512 Gb.
-
-## Integral performance
-
-Here showed sum of performance metrics in 3 benchmarks:
-
- - Read/Search on the machine with 4 logical CPUs in HyperThreading mode (i.e. actually 2 physical CPU cores);
-
- - Transactions with [CRUD](https://en.wikipedia.org/wiki/CRUD)
- operations in sync-write mode (fdatasync is called after each
- transaction);
-
- - Transactions with [CRUD](https://en.wikipedia.org/wiki/CRUD)
- operations in lazy-write mode (moment to sync data to persistent storage
- is decided by OS).
-
-*Reasons why asynchronous mode isn't benchmarked here:*
-
-  1. It doesn't make sense as it has to be done with DB engines, oriented
-  for keeping data in memory e.g. [Tarantool](https://tarantool.io/),
-  [Redis](https://redis.io/)), etc.
-
-  2. Performance gap is too high to compare in any meaningful way.
-
-![Comparison #1: Integral Performance](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/perf-slide-1.png)
-
---------------------------------------------------------------------------------
-
-## Read Scalability
-
-Summary performance with concurrent read/search queries in 1-2-4-8
-threads on the machine with 4 logical CPUs in HyperThreading mode (i.e. actually 2 physical CPU cores).
-
-![Comparison #2: Read Scalability](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/perf-slide-2.png)
-
---------------------------------------------------------------------------------
-
-## Sync-write mode
-
- - Linear scale on left and dark rectangles mean arithmetic mean
- transactions per second;
-
- - Logarithmic scale on right is in seconds and yellow intervals mean
- execution time of transactions. Each interval shows minimal and maximum
- execution time, cross marks standard deviation.
-
-**10,000 transactions in sync-write mode**. In case of a crash all data
-is consistent and conforms to the last successful transaction. The
-[fdatasync](https://linux.die.net/man/2/fdatasync) syscall is used after
-each write transaction in this mode.
-
-In the benchmark each transaction contains combined CRUD operations (2
-inserts, 1 read, 1 update, 1 delete). Benchmark starts on an empty database
-and after full run the database contains 10,000 small key-value records.
-
-![Comparison #3: Sync-write mode](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/perf-slide-3.png)
-
---------------------------------------------------------------------------------
-
-## Lazy-write mode
-
- - Linear scale on left and dark rectangles mean arithmetic mean of
- thousands transactions per second;
-
- - Logarithmic scale on right in seconds and yellow intervals mean
- execution time of transactions. Each interval shows minimal and maximum
- execution time, cross marks standard deviation.
-
-**100,000 transactions in lazy-write mode**. In case of a crash all data
-is consistent and conforms to the one of last successful transactions, but
-transactions after it will be lost. Other DB engines use
-[WAL](https://en.wikipedia.org/wiki/Write-ahead_logging) or transaction
-journal for that, which in turn depends on order of operations in the
-journaled filesystem. _libmdbx_ doesn't use WAL and hands I/O operations
-to filesystem and OS kernel (mmap).
-
-In the benchmark each transaction contains combined CRUD operations (2
-inserts, 1 read, 1 update, 1 delete). Benchmark starts on an empty database
-and after full run the database contains 100,000 small key-value
-records.
-
-
-![Comparison #4: Lazy-write mode](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/perf-slide-4.png)
-
---------------------------------------------------------------------------------
-
-## Async-write mode
-
- - Linear scale on left and dark rectangles mean arithmetic mean of
- thousands transactions per second;
-
- - Logarithmic scale on right in seconds and yellow intervals mean
- execution time of transactions. Each interval shows minimal and maximum
- execution time, cross marks standard deviation.
-
-**1,000,000 transactions in async-write mode**. In case of a crash all data is consistent and conforms to the one of last successful transactions, but lost transaction count is much higher than in
-lazy-write mode. All DB engines in this mode do as little writes as
-possible on persistent storage. _libmdbx_ uses
-[msync(MS_ASYNC)](https://linux.die.net/man/2/msync) in this mode.
-
-In the benchmark each transaction contains combined CRUD operations (2
-inserts, 1 read, 1 update, 1 delete). Benchmark starts on an empty database
-and after full run the database contains 10,000 small key-value records.
-
-![Comparison #5: Async-write mode](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/perf-slide-5.png)
-
---------------------------------------------------------------------------------
-
-## Cost comparison
-
-Summary of used resources during lazy-write mode benchmarks:
-
- - Read and write IOPs;
-
- - Sum of user CPU time and sys CPU time;
-
- - Used space on persistent storage after the test and closed DB, but not
- waiting for the end of all internal housekeeping operations (LSM
- compactification, etc).
-
-_ForestDB_ is excluded because benchmark showed it's resource
-consumption for each resource (CPU, IOPs) much higher than other engines
-which prevents to meaningfully compare it with them.
-
-All benchmark data is gathered by
-[getrusage()](http://man7.org/linux/man-pages/man2/getrusage.2.html)
-syscall and by scanning the data directory.
-
-![Comparison #6: Cost comparison](https://raw.githubusercontent.com/wiki/erthink/libmdbx/img/perf-slide-6.png)
-
-<!-- section-end -->
-
---------------------------------------------------------------------------------
-
-#### This is a mirror of the origin repository that was moved to [abf.io](https://abf.io/erthink/) because of discriminatory restrictions for Russian Crimea.
diff --git a/plugins/Dbx_mdbx/src/libmdbx/VERSION b/plugins/Dbx_mdbx/src/libmdbx/VERSION
deleted file mode 100644
index ad5a80ff3c..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/VERSION
+++ /dev/null
@@ -1 +0,0 @@
-0.9.2.136
diff --git a/plugins/Dbx_mdbx/src/libmdbx/config.h.in b/plugins/Dbx_mdbx/src/libmdbx/config.h.in
deleted file mode 100644
index bb3eea07b4..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/config.h.in
+++ /dev/null
@@ -1,63 +0,0 @@
-/* This is CMake-template for libmdbx's config.h
- ******************************************************************************/
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#cmakedefine LTO_ENABLED
-#cmakedefine MDBX_USE_VALGRIND
-#cmakedefine ENABLE_GPROF
-#cmakedefine ENABLE_GCOV
-#cmakedefine ENABLE_ASAN
-#cmakedefine ENABLE_UBSAN
-#cmakedefine MDBX_FORCE_ASSERTIONS
-
-/* Common */
-#cmakedefine01 MDBX_TXN_CHECKOWNER
-#cmakedefine MDBX_ENV_CHECKPID_AUTO
-#ifndef MDBX_ENV_CHECKPID_AUTO
-#cmakedefine01 MDBX_ENV_CHECKPID
-#endif
-#cmakedefine MDBX_LOCKING_AUTO
-#ifndef MDBX_LOCKING_AUTO
-#cmakedefine MDBX_LOCKING @MDBX_LOCKING@
-#endif
-#cmakedefine MDBX_TRUST_RTC_AUTO
-#ifndef MDBX_TRUST_RTC_AUTO
-#cmakedefine01 MDBX_TRUST_RTC
-#endif
-
-/* Windows */
-#cmakedefine01 MDBX_CONFIG_MANUAL_TLS_CALLBACK
-#cmakedefine01 MDBX_AVOID_CRT
-
-/* MacOS & iOS */
-#cmakedefine01 MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-
-/* POSIX */
-#cmakedefine01 MDBX_DISABLE_GNU_SOURCE
-#cmakedefine MDBX_USE_OFDLOCKS_AUTO
-#ifndef MDBX_USE_OFDLOCKS_AUTO
-#cmakedefine01 MDBX_USE_OFDLOCKS
-#endif
-
-/* Build Info */
-#ifndef MDBX_BUILD_TIMESTAMP
-#cmakedefine MDBX_BUILD_TIMESTAMP "@MDBX_BUILD_TIMESTAMP@"
-#endif
-#ifndef MDBX_BUILD_TARGET
-#cmakedefine MDBX_BUILD_TARGET "@MDBX_BUILD_TARGET@"
-#endif
-#ifndef MDBX_BUILD_TYPE
-#cmakedefine MDBX_BUILD_TYPE "@MDBX_BUILD_TYPE@"
-#endif
-#ifndef MDBX_BUILD_COMPILER
-#cmakedefine MDBX_BUILD_COMPILER "@MDBX_BUILD_COMPILER@"
-#endif
-#ifndef MDBX_BUILD_FLAGS
-#cmakedefine MDBX_BUILD_FLAGS "@MDBX_BUILD_FLAGS@"
-#endif
-#cmakedefine MDBX_BUILD_SOURCERY @MDBX_BUILD_SOURCERY@
-
-/* *INDENT-ON* */
-/* clang-format on */
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx.c b/plugins/Dbx_mdbx/src/libmdbx/mdbx.c
deleted file mode 100644
index 6ceafe5097..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx.c
+++ /dev/null
@@ -1,28388 +0,0 @@
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_ALLOY 1
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>.
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * This code is derived from "LMDB engine" written by
- * Howard Chu (Symas Corporation), which itself derived from btree.c
- * written by Martin Hedenfalk.
- *
- * ---
- *
- * Portions Copyright 2011-2015 Howard Chu, Symas Corp. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- *
- * ---
- *
- * Portions Copyright (c) 2009, 2010 Martin Hedenfalk <martin@bzero.se>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
-
-
-/*------------------------------------------------------------------------------
- * Internal inline functions */
-
-MDBX_NOTHROW_CONST_FUNCTION static unsigned log2n(size_t value) {
-  assert(value > 0 && value < INT32_MAX && is_powerof2(value));
-  assert((value & -(int32_t)value) == value);
-#if __GNUC_PREREQ(4, 1) || __has_builtin(__builtin_ctzl)
-  return __builtin_ctzl(value);
-#elif defined(_MSC_VER)
-  unsigned long index;
-  _BitScanForward(&index, (unsigned long)value);
-  return index;
-#else
-  static const uint8_t debruijn_ctz32[32] = {
-      0,  1,  28, 2,  29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4,  8,
-      31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6,  11, 5,  10, 9};
-  return debruijn_ctz32[(uint32_t)(value * 0x077CB531u) >> 27];
-#endif
-}
-
-/*------------------------------------------------------------------------------
- * Unaligned access */
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __always_inline unsigned
-field_alignment(unsigned alignment_baseline, size_t field_offset) {
-  unsigned merge = alignment_baseline | (unsigned)field_offset;
-  return merge & -(int)merge;
-}
-
-/* read-thunk for UB-sanitizer */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint8_t
-peek_u8(const uint8_t *const __restrict ptr) {
-  return *ptr;
-}
-
-/* write-thunk for UB-sanitizer */
-static __always_inline void poke_u8(uint8_t *const __restrict ptr,
-                                    const uint8_t v) {
-  *ptr = v;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint16_t
-unaligned_peek_u16(const unsigned expected_alignment, const void *const ptr) {
-  assert((uintptr_t)ptr % expected_alignment == 0);
-  if (MDBX_UNALIGNED_OK || (expected_alignment % sizeof(uint16_t)) == 0)
-    return *(const uint16_t *)ptr;
-  else {
-    uint16_t v;
-    memcpy(&v, ptr, sizeof(v));
-    return v;
-  }
-}
-
-static __always_inline void
-unaligned_poke_u16(const unsigned expected_alignment,
-                   void *const __restrict ptr, const uint16_t v) {
-  assert((uintptr_t)ptr % expected_alignment == 0);
-  if (MDBX_UNALIGNED_OK || (expected_alignment % sizeof(v)) == 0)
-    *(uint16_t *)ptr = v;
-  else
-    memcpy(ptr, &v, sizeof(v));
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint32_t unaligned_peek_u32(
-    const unsigned expected_alignment, const void *const __restrict ptr) {
-  assert((uintptr_t)ptr % expected_alignment == 0);
-  if (MDBX_UNALIGNED_OK || (expected_alignment % sizeof(uint32_t)) == 0)
-    return *(const uint32_t *)ptr;
-  else if ((expected_alignment % sizeof(uint16_t)) == 0) {
-    const uint16_t lo =
-        ((const uint16_t *)ptr)[__BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__];
-    const uint16_t hi =
-        ((const uint16_t *)ptr)[__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__];
-    return lo | (uint32_t)hi << 16;
-  } else {
-    uint32_t v;
-    memcpy(&v, ptr, sizeof(v));
-    return v;
-  }
-}
-
-static __always_inline void
-unaligned_poke_u32(const unsigned expected_alignment,
-                   void *const __restrict ptr, const uint32_t v) {
-  assert((uintptr_t)ptr % expected_alignment == 0);
-  if (MDBX_UNALIGNED_OK || (expected_alignment % sizeof(v)) == 0)
-    *(uint32_t *)ptr = v;
-  else if ((expected_alignment % sizeof(uint16_t)) == 0) {
-    ((uint16_t *)ptr)[__BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__] = (uint16_t)v;
-    ((uint16_t *)ptr)[__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__] =
-        (uint16_t)(v >> 16);
-  } else
-    memcpy(ptr, &v, sizeof(v));
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint64_t unaligned_peek_u64(
-    const unsigned expected_alignment, const void *const __restrict ptr) {
-  assert((uintptr_t)ptr % expected_alignment == 0);
-  if (MDBX_UNALIGNED_OK || (expected_alignment % sizeof(uint64_t)) == 0)
-    return *(const uint64_t *)ptr;
-  else if ((expected_alignment % sizeof(uint32_t)) == 0) {
-    const uint32_t lo =
-        ((const uint32_t *)ptr)[__BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__];
-    const uint32_t hi =
-        ((const uint32_t *)ptr)[__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__];
-    return lo | (uint64_t)hi << 32;
-  } else {
-    uint64_t v;
-    memcpy(&v, ptr, sizeof(v));
-    return v;
-  }
-}
-
-static __always_inline void
-unaligned_poke_u64(const unsigned expected_alignment,
-                   void *const __restrict ptr, const uint64_t v) {
-  assert((uintptr_t)ptr % expected_alignment == 0);
-  if (MDBX_UNALIGNED_OK || (expected_alignment % sizeof(v)) == 0)
-    *(uint64_t *)ptr = v;
-  else if ((expected_alignment % sizeof(uint32_t)) == 0) {
-    ((uint32_t *)ptr)[__BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__] = (uint32_t)v;
-    ((uint32_t *)ptr)[__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__] =
-        (uint32_t)(v >> 32);
-  } else
-    memcpy(ptr, &v, sizeof(v));
-}
-
-#define UNALIGNED_PEEK_8(ptr, struct, field)                                   \
-  peek_u8((const uint8_t *)(ptr) + offsetof(struct, field))
-#define UNALIGNED_POKE_8(ptr, struct, field, value)                            \
-  poke_u8((uint8_t *)(ptr) + offsetof(struct, field), value)
-
-#define UNALIGNED_PEEK_16(ptr, struct, field)                                  \
-  unaligned_peek_u16(1, (const char *)(ptr) + offsetof(struct, field))
-#define UNALIGNED_POKE_16(ptr, struct, field, value)                           \
-  unaligned_poke_u16(1, (char *)(ptr) + offsetof(struct, field), value)
-
-#define UNALIGNED_PEEK_32(ptr, struct, field)                                  \
-  unaligned_peek_u32(1, (const char *)(ptr) + offsetof(struct, field))
-#define UNALIGNED_POKE_32(ptr, struct, field, value)                           \
-  unaligned_poke_u32(1, (char *)(ptr) + offsetof(struct, field), value)
-
-#define UNALIGNED_PEEK_64(ptr, struct, field)                                  \
-  unaligned_peek_u64(1, (const char *)(ptr) + offsetof(struct, field))
-#define UNALIGNED_POKE_64(ptr, struct, field, value)                           \
-  unaligned_poke_u64(1, (char *)(ptr) + offsetof(struct, field), value)
-
-/* Get the page number pointed to by a branch node */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline pgno_t
-node_pgno(const MDBX_node *const __restrict node) {
-  pgno_t pgno = UNALIGNED_PEEK_32(node, MDBX_node, mn_pgno32);
-  if (sizeof(pgno) > 4)
-    pgno |= ((uint64_t)UNALIGNED_PEEK_8(node, MDBX_node, mn_extra)) << 32;
-  return pgno;
-}
-
-/* Set the page number in a branch node */
-static __always_inline void node_set_pgno(MDBX_node *const __restrict node,
-                                          pgno_t pgno) {
-  assert(pgno >= MIN_PAGENO && pgno <= MAX_PAGENO);
-
-  UNALIGNED_POKE_32(node, MDBX_node, mn_pgno32, (uint32_t)pgno);
-  if (sizeof(pgno) > 4)
-    UNALIGNED_POKE_8(node, MDBX_node, mn_extra,
-                     (uint8_t)((uint64_t)pgno >> 32));
-}
-
-/* Get the size of the data in a leaf node */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline size_t
-node_ds(const MDBX_node *const __restrict node) {
-  return UNALIGNED_PEEK_32(node, MDBX_node, mn_dsize);
-}
-
-/* Set the size of the data for a leaf node */
-static __always_inline void node_set_ds(MDBX_node *const __restrict node,
-                                        size_t size) {
-  assert(size < INT_MAX);
-  UNALIGNED_POKE_32(node, MDBX_node, mn_dsize, (uint32_t)size);
-}
-
-/* The size of a key in a node */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline size_t
-node_ks(const MDBX_node *const __restrict node) {
-  return UNALIGNED_PEEK_16(node, MDBX_node, mn_ksize);
-}
-
-/* Set the size of the key for a leaf node */
-static __always_inline void node_set_ks(MDBX_node *const __restrict node,
-                                        size_t size) {
-  assert(size < INT16_MAX);
-  UNALIGNED_POKE_16(node, MDBX_node, mn_ksize, (uint16_t)size);
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline uint8_t
-node_flags(const MDBX_node *const __restrict node) {
-  return UNALIGNED_PEEK_8(node, MDBX_node, mn_flags);
-}
-
-static __always_inline void node_set_flags(MDBX_node *const __restrict node,
-                                           uint8_t flags) {
-  UNALIGNED_POKE_8(node, MDBX_node, mn_flags, flags);
-}
-
-/* Size of the node header, excluding dynamic data at the end */
-#define NODESIZE offsetof(MDBX_node, mn_data)
-
-/* Address of the key for the node */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline void *
-node_key(const MDBX_node *const __restrict node) {
-  return (char *)node + NODESIZE;
-}
-
-/* Address of the data for a node */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline void *
-node_data(const MDBX_node *const __restrict node) {
-  return (char *)node_key(node) + node_ks(node);
-}
-
-/* Size of a node in a leaf page with a given key and data.
- * This is node header plus key plus data size. */
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline size_t
-node_size_len(const size_t key_len, const size_t value_len) {
-  return NODESIZE + EVEN(key_len + value_len);
-}
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline size_t
-node_size(const MDBX_val *key, const MDBX_val *value) {
-  return node_size_len(key ? key->iov_len : 0, value ? value->iov_len : 0);
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline pgno_t
-peek_pgno(const void *const __restrict ptr) {
-  if (sizeof(pgno_t) == sizeof(uint32_t))
-    return (pgno_t)unaligned_peek_u32(1, ptr);
-  else if (sizeof(pgno_t) == sizeof(uint64_t))
-    return (pgno_t)unaligned_peek_u64(1, ptr);
-  else {
-    pgno_t pgno;
-    memcpy(&pgno, ptr, sizeof(pgno));
-    return pgno;
-  }
-}
-
-static __always_inline void poke_pgno(void *const __restrict ptr,
-                                      const pgno_t pgno) {
-  if (sizeof(pgno) == sizeof(uint32_t))
-    unaligned_poke_u32(1, ptr, pgno);
-  else if (sizeof(pgno) == sizeof(uint64_t))
-    unaligned_poke_u64(1, ptr, pgno);
-  else
-    memcpy(ptr, &pgno, sizeof(pgno));
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline pgno_t
-node_largedata_pgno(const MDBX_node *const __restrict node) {
-  assert(node_flags(node) & F_BIGDATA);
-  return peek_pgno(node_data(node));
-}
-
-/*------------------------------------------------------------------------------
- * Key length limitation factors:
- *
- *  - Branch-page must contain at least two (MDBX_MINKEYS) nodes,
- *    within each a key and a child page number. But we can't split a page if
- *    it contains less that 4 keys. Therefore, at least 3 branch-node should
- *    fit in the single branch-page:
- *      pageroom = pagesize - page_hdr_len;
- *      branch.maxnode = even_floor(pageroom / 3 - sizeof(indx_t));
- *      branch.maxkey = branch.maxnode - node_hdr_len;
- *
- *  - Leaf-node of non-dupsort database must fit into one leaf-page,
- *    where a value could be placed on a large/overflow page:
- *      leaf.maxnode = even_floor(pageroom - sizeof(indx_t));
- *      leaf.maxkey = leaf.maxnode - node_hdr_len - sizeof(pgno_t);
- *
- *  - SubDatabase-node must fit into one leaf-page:
- *      subdb.maxname = leaf.maxnode - node_hdr_len - sizeof(MDBX_db);
- *
- *  - Dupsort values itself are a keys in a dupsort-subdb and couldn't be
- *    longer than the branch.maxkey. But dupsort node must fit into one
- *    leaf-page, since dupsort value couldn't be placed on a large/overflow
- *    page.
- *
- * - So, the simplest solution is to use half of branch.maxkey as
- *   a common maxkey value. Nevertheless, the actual values of maxkey are:
- *     nondupsort.maxkey = even_floor(pageroom / 3)
- *                           - sizeof(indx_t) - node_hdr_len;
- *     dupsort.maxkey(value) = min(nondupsort.maxkey,
- *                                 leaf.maxnode - even_ceil(length(value)));
- */
-
-#define PAGEROOM(pagesize) ((pagesize)-PAGEHDRSZ)
-#define EVEN_FLOOR(n) ((n) & ~(size_t)1)
-#define BRANCH_NODEMAX(pagesize)                                               \
-  (EVEN_FLOOR(PAGEROOM(pagesize) / (MDBX_MINKEYS * 2 - 1)) - sizeof(indx_t))
-#define LEAF_NODEMAX(pagesize) (PAGEROOM(pagesize) - sizeof(indx_t))
-#define MAX_GC1OVPAGE(pagesize) (PAGEROOM(pagesize) / sizeof(pgno_t) - 1)
-
-__cold int mdbx_env_get_maxkeysize(const MDBX_env *env) {
-  return mdbx_env_get_maxkeysize_ex(env, MDBX_DUPSORT);
-}
-
-__cold int mdbx_env_get_maxkeysize_ex(const MDBX_env *env,
-                                      MDBX_db_flags_t flags) {
-  if (unlikely(!env || env->me_signature.weak != MDBX_ME_SIGNATURE))
-    return -1;
-
-  return (int)mdbx_limits_keysize_max((intptr_t)env->me_psize, flags);
-}
-
-size_t mdbx_default_pagesize(void) {
-  size_t pagesize = mdbx_syspagesize();
-  mdbx_ensure(nullptr, is_powerof2(pagesize));
-  pagesize = (pagesize >= MIN_PAGESIZE) ? pagesize : MIN_PAGESIZE;
-  pagesize = (pagesize <= MAX_PAGESIZE) ? pagesize : MAX_PAGESIZE;
-  return pagesize;
-}
-
-__cold intptr_t mdbx_limits_keysize_max(intptr_t pagesize,
-                                        MDBX_db_flags_t flags) {
-  if (pagesize < 1)
-    pagesize = (intptr_t)mdbx_default_pagesize();
-  if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
-               pagesize > (intptr_t)MAX_PAGESIZE ||
-               !is_powerof2((size_t)pagesize)))
-    return -1;
-
-  STATIC_ASSERT(BRANCH_NODEMAX(MIN_PAGESIZE) - NODESIZE - sizeof(pgno_t) >= 8);
-  STATIC_ASSERT(LEAF_NODEMAX(MIN_PAGESIZE) - NODESIZE - sizeof(pgno_t) >= 8);
-  STATIC_ASSERT(LEAF_NODEMAX(MIN_PAGESIZE) - NODESIZE >= sizeof(MDBX_db));
-  if (flags & MDBX_INTEGERKEY)
-    return 8 /* sizeof(uint64_t) */;
-
-  STATIC_ASSERT(BRANCH_NODEMAX(MAX_PAGESIZE) - NODESIZE - sizeof(pgno_t) <
-                LEAF_NODEMAX(MAX_PAGESIZE) - NODESIZE - sizeof(MDBX_db));
-  STATIC_ASSERT(BRANCH_NODEMAX(MIN_PAGESIZE) - NODESIZE - sizeof(pgno_t) <
-                LEAF_NODEMAX(MIN_PAGESIZE) - NODESIZE - sizeof(MDBX_db));
-  if (flags &
-      (MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP))
-    return BRANCH_NODEMAX(pagesize) - NODESIZE - sizeof(MDBX_db);
-
-  return BRANCH_NODEMAX(pagesize) - NODESIZE - sizeof(pgno_t);
-}
-
-__cold int mdbx_env_get_maxvalsize_ex(const MDBX_env *env,
-                                      MDBX_db_flags_t flags) {
-  if (unlikely(!env || env->me_signature.weak != MDBX_ME_SIGNATURE))
-    return -1;
-
-  return (int)mdbx_limits_valsize_max((intptr_t)env->me_psize, flags);
-}
-
-__cold intptr_t mdbx_limits_valsize_max(intptr_t pagesize,
-                                        MDBX_db_flags_t flags) {
-  if (pagesize < 1)
-    pagesize = (intptr_t)mdbx_default_pagesize();
-  if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
-               pagesize > (intptr_t)MAX_PAGESIZE ||
-               !is_powerof2((size_t)pagesize)))
-    return -1;
-
-  if (flags & MDBX_INTEGERDUP)
-    return 8 /* sizeof(uint64_t) */;
-
-  if (flags & (MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_REVERSEDUP))
-    return BRANCH_NODEMAX(pagesize) - NODESIZE;
-
-  const unsigned page_ln2 = log2n(pagesize);
-  const size_t hard = 0x7FF00000ul;
-  const size_t hard_pages = hard >> page_ln2;
-  STATIC_ASSERT(MDBX_PGL_LIMIT <= MAX_PAGENO);
-  const size_t pages_limit = MDBX_PGL_LIMIT / 4;
-  const size_t limit =
-      (hard_pages < pages_limit) ? hard : (pages_limit << page_ln2);
-  return (limit < MAX_MAPSIZE / 2) ? limit : MAX_MAPSIZE / 2;
-}
-
-/* Calculate the size of a leaf node.
- *
- * The size depends on the environment's page size; if a data item
- * is too large it will be put onto an overflow page and the node
- * size will only include the key and not the data. Sizes are always
- * rounded up to an even number of bytes, to guarantee 2-byte alignment
- * of the MDBX_node headers. */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline size_t
-leaf_size(const MDBX_env *env, const MDBX_val *key, const MDBX_val *data) {
-  size_t node_bytes = node_size(key, data);
-  /* NOTE: The actual limit is LEAF_NODEMAX(env->me_psize), but it reasonable to
-   * use env->me_branch_nodemax (which is 3 times less) as the threshold
-   * because:
-   *  - Large threshold implies that any insertion/update could result split
-   *    a single leaf page to THREE, which requires TWO insertion into parent
-   *    branch page, then could leads to split parent page and so on up to
-   *    the root. Such double-splitting is complex, ie costly (in case simple
-   *    clear implementation) either dangerous (in case high-optimized
-   *    implementation).
-   *  - This does not affect capabilities, i.e. it does not limit the maximum
-   *    key size.
-   *  - At a lower threshold, on average, the density of keys on leaf pages
-   *    increases and the height of the tree decreases. Thus, this lead the
-   *    less number of pages participating in the search, and the search
-   *    speed increases.
-   *  - On the other hand, there is no universal gold ratio here and with a
-   *    smaller threshold, we will create more overflows/large pages,
-   *    i.e. the database size will be larger as will the IOPS volume.
-   *
-   * So, the lower threshold is not a silver bullet, but it allow implementation
-   * to be much simple and robust, without adding a flaws. */
-  if (node_bytes > env->me_branch_nodemax) {
-    /* put on overflow page */
-    node_bytes = node_size(key, nullptr) + sizeof(pgno_t);
-  }
-
-  return node_bytes + sizeof(indx_t);
-}
-
-/* Calculate the size of a branch node.
- *
- * The size should depend on the environment's page size but since
- * we currently don't support spilling large keys onto overflow
- * pages, it's simply the size of the MDBX_node header plus the
- * size of the key. Sizes are always rounded up to an even number
- * of bytes, to guarantee 2-byte alignment of the MDBX_node headers.
- *
- * [in] env The environment handle.
- * [in] key The key for the node.
- *
- * Returns The number of bytes needed to store the node. */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline size_t
-branch_size(const MDBX_env *env, const MDBX_val *key) {
-  /* Size of a node in a branch page with a given key.
-   * This is just the node header plus the key, there is no data. */
-  size_t node_bytes = node_size(key, nullptr);
-  if (unlikely(node_bytes > env->me_branch_nodemax)) {
-    /* put on overflow page */
-    /* not implemented */
-    mdbx_assert_fail(env, "INDXSIZE(key) <= env->me_nodemax", __func__,
-                     __LINE__);
-    node_bytes = node_size(key, nullptr) + sizeof(pgno_t);
-  }
-
-  return node_bytes + sizeof(indx_t);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline uint16_t
-flags_db2sub(uint16_t db_flags) {
-  uint16_t sub_flags = db_flags & MDBX_DUPFIXED;
-
-  /* MDBX_INTEGERDUP => MDBX_INTEGERKEY */
-#define SHIFT_INTEGERDUP_TO_INTEGERKEY 2
-  STATIC_ASSERT((MDBX_INTEGERDUP >> SHIFT_INTEGERDUP_TO_INTEGERKEY) ==
-                MDBX_INTEGERKEY);
-  sub_flags |= (db_flags & MDBX_INTEGERDUP) >> SHIFT_INTEGERDUP_TO_INTEGERKEY;
-
-  /* MDBX_REVERSEDUP => MDBX_REVERSEKEY */
-#define SHIFT_REVERSEDUP_TO_REVERSEKEY 5
-  STATIC_ASSERT((MDBX_REVERSEDUP >> SHIFT_REVERSEDUP_TO_REVERSEKEY) ==
-                MDBX_REVERSEKEY);
-  sub_flags |= (db_flags & MDBX_REVERSEDUP) >> SHIFT_REVERSEDUP_TO_REVERSEKEY;
-
-  return sub_flags;
-}
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline size_t
-pgno2bytes(const MDBX_env *env, pgno_t pgno) {
-  mdbx_assert(env, (1u << env->me_psize2log) == env->me_psize);
-  return ((size_t)pgno) << env->me_psize2log;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline MDBX_page *
-pgno2page(const MDBX_env *env, pgno_t pgno) {
-  return (MDBX_page *)(env->me_map + pgno2bytes(env, pgno));
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline pgno_t
-bytes2pgno(const MDBX_env *env, size_t bytes) {
-  mdbx_assert(env, (env->me_psize >> env->me_psize2log) == 1);
-  return (pgno_t)(bytes >> env->me_psize2log);
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static size_t
-pgno_align2os_bytes(const MDBX_env *env, pgno_t pgno) {
-  return ceil_powerof2(pgno2bytes(env, pgno), env->me_os_psize);
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static pgno_t pgno_align2os_pgno(const MDBX_env *env,
-                                                            pgno_t pgno) {
-  return bytes2pgno(env, pgno_align2os_bytes(env, pgno));
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static size_t
-bytes_align2os_bytes(const MDBX_env *env, size_t bytes) {
-  return ceil_powerof2(ceil_powerof2(bytes, env->me_psize), env->me_os_psize);
-}
-
-/* Address of first usable data byte in a page, after the header */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline void *
-page_data(const MDBX_page *mp) {
-  return (char *)mp + PAGEHDRSZ;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline const MDBX_page *
-data_page(const void *data) {
-  return container_of(data, MDBX_page, mp_ptrs);
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline MDBX_meta *
-page_meta(MDBX_page *mp) {
-  return (MDBX_meta *)page_data(mp);
-}
-
-/* Number of nodes on a page */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline unsigned
-page_numkeys(const MDBX_page *mp) {
-  return mp->mp_lower >> 1;
-}
-
-/* The amount of space remaining in the page */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline unsigned
-page_room(const MDBX_page *mp) {
-  return mp->mp_upper - mp->mp_lower;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline unsigned
-page_space(const MDBX_env *env) {
-  STATIC_ASSERT(PAGEHDRSZ % 2 == 0);
-  return env->me_psize - PAGEHDRSZ;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline unsigned
-page_used(const MDBX_env *env, const MDBX_page *mp) {
-  return page_space(env) - page_room(mp);
-}
-
-/* The percentage of space used in the page, in a percents. */
-MDBX_NOTHROW_PURE_FUNCTION static __maybe_unused __inline double
-page_fill(const MDBX_env *env, const MDBX_page *mp) {
-  return page_used(env, mp) * 100.0 / page_space(env);
-}
-
-/* The number of overflow pages needed to store the given size. */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline pgno_t
-number_of_ovpages(const MDBX_env *env, size_t bytes) {
-  return bytes2pgno(env, PAGEHDRSZ - 1 + bytes) + 1;
-}
-
-__cold static int MDBX_PRINTF_ARGS(2, 3)
-    bad_page(const MDBX_page *mp, const char *fmt, ...) {
-  if (mdbx_log_enabled(MDBX_LOG_ERROR)) {
-    static const MDBX_page *prev;
-    if (prev != mp) {
-      prev = mp;
-      mdbx_debug_log(MDBX_LOG_ERROR, "badpage", 0,
-                     "corrupted page #%u, mod-txnid %" PRIaTXN "\n",
-                     mp->mp_pgno, mp->mp_txnid);
-    }
-
-    va_list args;
-    va_start(args, fmt);
-    mdbx_debug_log_va(MDBX_LOG_ERROR, "badpage", 0, fmt, args);
-    va_end(args);
-  }
-  return MDBX_CORRUPTED;
-}
-
-/* Address of node i in page p */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline MDBX_node *
-page_node(const MDBX_page *mp, unsigned i) {
-  assert((mp->mp_flags & (P_LEAF2 | P_OVERFLOW | P_META)) == 0);
-  assert(page_numkeys(mp) > (unsigned)(i));
-  assert(mp->mp_ptrs[i] % 2 == 0);
-  return (MDBX_node *)((char *)mp + mp->mp_ptrs[i] + PAGEHDRSZ);
-}
-
-/* The address of a key in a LEAF2 page.
- * LEAF2 pages are used for MDBX_DUPFIXED sorted-duplicate sub-DBs.
- * There are no node headers, keys are stored contiguously. */
-MDBX_NOTHROW_PURE_FUNCTION static __always_inline void *
-page_leaf2key(const MDBX_page *mp, unsigned i, size_t keysize) {
-  assert((mp->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW | P_META)) ==
-         (P_LEAF | P_LEAF2));
-  assert(mp->mp_leaf2_ksize == keysize);
-  (void)keysize;
-  return (char *)mp + PAGEHDRSZ + (i * mp->mp_leaf2_ksize);
-}
-
-/* Set the node's key into keyptr. */
-static __always_inline void get_key(const MDBX_node *node, MDBX_val *keyptr) {
-  keyptr->iov_len = node_ks(node);
-  keyptr->iov_base = node_key(node);
-}
-
-/* Set the node's key into keyptr, if requested. */
-static __always_inline void
-get_key_optional(const MDBX_node *node, MDBX_val *keyptr /* __may_null */) {
-  if (keyptr)
-    get_key(node, keyptr);
-}
-
-/*------------------------------------------------------------------------------
- * Workaround for mmaped-lookahead-cross-page-boundary bug
- * in an obsolete versions of Elbrus's libc and kernels. */
-#if defined(__e2k__) && defined(MDBX_E2K_MLHCPB_WORKAROUND) &&                 \
-    MDBX_E2K_MLHCPB_WORKAROUND
-int __hot mdbx_e2k_memcmp_bug_workaround(const void *s1, const void *s2,
-                                         size_t n) {
-  if (unlikely(n > 42
-               /* LY: align followed access if reasonable possible */
-               && (((uintptr_t)s1) & 7) != 0 &&
-               (((uintptr_t)s1) & 7) == (((uintptr_t)s2) & 7))) {
-    if (((uintptr_t)s1) & 1) {
-      const int diff = *(uint8_t *)s1 - *(uint8_t *)s2;
-      if (diff)
-        return diff;
-      s1 = (char *)s1 + 1;
-      s2 = (char *)s2 + 1;
-      n -= 1;
-    }
-
-    if (((uintptr_t)s1) & 2) {
-      const uint16_t a = *(uint16_t *)s1;
-      const uint16_t b = *(uint16_t *)s2;
-      if (likely(a != b))
-        return (__builtin_bswap16(a) > __builtin_bswap16(b)) ? 1 : -1;
-      s1 = (char *)s1 + 2;
-      s2 = (char *)s2 + 2;
-      n -= 2;
-    }
-
-    if (((uintptr_t)s1) & 4) {
-      const uint32_t a = *(uint32_t *)s1;
-      const uint32_t b = *(uint32_t *)s2;
-      if (likely(a != b))
-        return (__builtin_bswap32(a) > __builtin_bswap32(b)) ? 1 : -1;
-      s1 = (char *)s1 + 4;
-      s2 = (char *)s2 + 4;
-      n -= 4;
-    }
-  }
-
-  while (n >= 8) {
-    const uint64_t a = *(uint64_t *)s1;
-    const uint64_t b = *(uint64_t *)s2;
-    if (likely(a != b))
-      return (__builtin_bswap64(a) > __builtin_bswap64(b)) ? 1 : -1;
-    s1 = (char *)s1 + 8;
-    s2 = (char *)s2 + 8;
-    n -= 8;
-  }
-
-  if (n & 4) {
-    const uint32_t a = *(uint32_t *)s1;
-    const uint32_t b = *(uint32_t *)s2;
-    if (likely(a != b))
-      return (__builtin_bswap32(a) > __builtin_bswap32(b)) ? 1 : -1;
-    s1 = (char *)s1 + 4;
-    s2 = (char *)s2 + 4;
-  }
-
-  if (n & 2) {
-    const uint16_t a = *(uint16_t *)s1;
-    const uint16_t b = *(uint16_t *)s2;
-    if (likely(a != b))
-      return (__builtin_bswap16(a) > __builtin_bswap16(b)) ? 1 : -1;
-    s1 = (char *)s1 + 2;
-    s2 = (char *)s2 + 2;
-  }
-
-  return (n & 1) ? *(uint8_t *)s1 - *(uint8_t *)s2 : 0;
-}
-
-int __hot mdbx_e2k_strcmp_bug_workaround(const char *s1, const char *s2) {
-  while (true) {
-    int diff = *(uint8_t *)s1 - *(uint8_t *)s2;
-    if (likely(diff != 0) || *s1 == '\0')
-      return diff;
-    s1 += 1;
-    s2 += 1;
-  }
-}
-
-int __hot mdbx_e2k_strncmp_bug_workaround(const char *s1, const char *s2,
-                                          size_t n) {
-  while (n > 0) {
-    int diff = *(uint8_t *)s1 - *(uint8_t *)s2;
-    if (likely(diff != 0) || *s1 == '\0')
-      return diff;
-    s1 += 1;
-    s2 += 1;
-    n -= 1;
-  }
-  return 0;
-}
-
-size_t __hot mdbx_e2k_strlen_bug_workaround(const char *s) {
-  size_t n = 0;
-  while (*s) {
-    s += 1;
-    n += 1;
-  }
-  return n;
-}
-
-size_t __hot mdbx_e2k_strnlen_bug_workaround(const char *s, size_t maxlen) {
-  size_t n = 0;
-  while (maxlen > n && *s) {
-    s += 1;
-    n += 1;
-  }
-  return n;
-}
-#endif /* MDBX_E2K_MLHCPB_WORKAROUND */
-
-/*------------------------------------------------------------------------------
- * safe read/write volatile 64-bit fields on 32-bit architectures. */
-
-enum MDBX_memory_order {
-  mo_Relaxed,
-  mo_AcquireRelease,
-  mo_SequentialConsistency
-};
-
-#ifdef MDBX_HAVE_C11ATOMICS
-
-#if defined(__clang__) && __clang__ < 8
-#define MDBX_WORKAROUND_CLANG_C11ATOMICS_BUG(type, ptr)                        \
-  ((volatile _Atomic(type) *)(ptr))
-#else
-#define MDBX_WORKAROUND_CLANG_C11ATOMICS_BUG(type, ptr) (ptr)
-#endif /* __clang__ < 8.x */
-
-static __always_inline memory_order mo_c11_store(enum MDBX_memory_order fence) {
-  switch (fence) {
-  default:
-    assert(false);
-    __unreachable();
-  case mo_Relaxed:
-    return memory_order_relaxed;
-  case mo_AcquireRelease:
-    return memory_order_release;
-  case mo_SequentialConsistency:
-    return memory_order_seq_cst;
-  }
-}
-
-static __always_inline memory_order mo_c11_load(enum MDBX_memory_order fence) {
-  switch (fence) {
-  default:
-    assert(false);
-    __unreachable();
-  case mo_Relaxed:
-    return memory_order_relaxed;
-  case mo_AcquireRelease:
-    return memory_order_acquire;
-  case mo_SequentialConsistency:
-    return memory_order_seq_cst;
-  }
-}
-#endif /* MDBX_HAVE_C11ATOMICS */
-
-static __maybe_unused __always_inline void mdbx_memory_fence(bool checkpoint,
-                                                             bool write) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(
-      checkpoint ? memory_order_seq_cst
-                 : (write ? memory_order_release : memory_order_acquire));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  mdbx_compiler_barrier();
-  if (checkpoint || (write && MDBX_CPU_WRITEBACK_INCOHERENT))
-    mdbx_memory_barrier();
-#endif /* MDBX_HAVE_C11ATOMICS */
-}
-
-static __maybe_unused __always_inline uint32_t
-atomic_store32(MDBX_atomic_uint32_t *ptr, const uint32_t value,
-               enum MDBX_memory_order order) {
-  STATIC_ASSERT(sizeof(MDBX_atomic_uint32_t) == 4);
-#ifdef MDBX_HAVE_C11ATOMICS
-  assert(atomic_is_lock_free(&ptr->c11a));
-  atomic_store_explicit(&ptr->c11a, value, mo_c11_store(order));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  if (order != mo_Relaxed)
-    mdbx_compiler_barrier();
-  ptr->weak = value;
-  if (order != mo_Relaxed)
-    mdbx_memory_fence(order == mo_SequentialConsistency, true);
-#endif /* MDBX_HAVE_C11ATOMICS */
-  return value;
-}
-
-static __maybe_unused __always_inline uint32_t
-atomic_load32(const MDBX_atomic_uint32_t *ptr, enum MDBX_memory_order order) {
-  STATIC_ASSERT(sizeof(MDBX_atomic_uint32_t) == 4);
-#ifdef MDBX_HAVE_C11ATOMICS
-  assert(atomic_is_lock_free(&ptr->c11a));
-  return atomic_load_explicit(
-      MDBX_WORKAROUND_CLANG_C11ATOMICS_BUG(uint32_t, &ptr->c11a),
-      mo_c11_load(order));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  if (order != mo_Relaxed)
-    mdbx_memory_fence(order == mo_SequentialConsistency, false);
-  const uint32_t value = ptr->weak;
-  if (order != mo_Relaxed)
-    mdbx_compiler_barrier();
-  return value;
-#endif /* MDBX_HAVE_C11ATOMICS */
-}
-
-static __always_inline uint64_t atomic_store64(MDBX_atomic_uint64_t *ptr,
-                                               const uint64_t value,
-                                               enum MDBX_memory_order order) {
-  STATIC_ASSERT(sizeof(MDBX_atomic_uint64_t) == 8);
-#if MDBX_64BIT_ATOMIC
-#ifdef MDBX_HAVE_C11ATOMICS
-  assert(atomic_is_lock_free(&ptr->c11a));
-  atomic_store_explicit(&ptr->c11a, value, mo_c11_store(order));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  if (order != mo_Relaxed)
-    mdbx_compiler_barrier();
-  ptr->weak = value;
-  if (order != mo_Relaxed)
-    mdbx_memory_fence(order == mo_SequentialConsistency, true);
-#endif /* MDBX_HAVE_C11ATOMICS */
-#else  /* !MDBX_64BIT_ATOMIC */
-  atomic_store32(&ptr->low, (uint32_t)value,
-                 (order == mo_Relaxed) ? mo_Relaxed : mo_AcquireRelease);
-  mdbx_jitter4testing(true);
-  atomic_store32(&ptr->high, (uint32_t)(value >> 32), order);
-  mdbx_jitter4testing(true);
-#endif /* !MDBX_64BIT_ATOMIC */
-  return value;
-}
-
-static __always_inline uint64_t atomic_load64(const MDBX_atomic_uint64_t *ptr,
-                                              enum MDBX_memory_order order) {
-  STATIC_ASSERT(sizeof(MDBX_atomic_uint64_t) == 8);
-#if MDBX_64BIT_ATOMIC
-#ifdef MDBX_HAVE_C11ATOMICS
-  assert(atomic_is_lock_free(&ptr->c11a));
-  return atomic_load_explicit(
-      MDBX_WORKAROUND_CLANG_C11ATOMICS_BUG(uint64_t, &ptr->c11a),
-      mo_c11_load(order));
-#else  /* MDBX_HAVE_C11ATOMICS */
-  if (order != mo_Relaxed)
-    mdbx_memory_fence(order == mo_SequentialConsistency, false);
-  const uint64_t value = ptr->weak;
-  if (order != mo_Relaxed)
-    mdbx_compiler_barrier();
-  return value;
-#endif /* MDBX_HAVE_C11ATOMICS */
-#else  /* !MDBX_64BIT_ATOMIC */
-  uint64_t value = (uint64_t)atomic_load32(&ptr->high, order) << 32;
-  mdbx_jitter4testing(true);
-  value |= atomic_load32(&ptr->low, (order == mo_Relaxed) ? mo_Relaxed
-                                                          : mo_AcquireRelease);
-  mdbx_jitter4testing(true);
-  for (;;) {
-    uint64_t again = (uint64_t)atomic_load32(&ptr->high, order) << 32;
-    mdbx_jitter4testing(true);
-    again |= atomic_load32(
-        &ptr->low, (order == mo_Relaxed) ? mo_Relaxed : mo_AcquireRelease);
-    mdbx_jitter4testing(true);
-    if (likely(value == again))
-      return value;
-    value = again;
-  }
-#endif /* !MDBX_64BIT_ATOMIC */
-}
-
-static __always_inline void atomic_yield(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  YieldProcessor();
-#elif defined(__ia32__) || defined(__e2k__)
-  __builtin_ia32_pause();
-#elif defined(__ia64__)
-#if defined(__HP_cc__) || defined(__HP_aCC__)
-  _Asm_hint(_HINT_PAUSE);
-#else
-  __asm__ __volatile__("hint @pause");
-#endif
-#elif defined(__aarch64__) || (defined(__ARM_ARCH) && __ARM_ARCH > 6) ||       \
-    defined(__ARM_ARCH_6K__)
-#ifdef __CC_ARM
-  __yield();
-#else
-  __asm__ __volatile__("yield");
-#endif
-#elif (defined(__mips64) || defined(__mips64__)) && defined(__mips_isa_rev) && \
-    __mips_isa_rev >= 2
-  __asm__ __volatile__("pause");
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-  __asm__ __volatile__(".word 0x00000140");
-#elif defined(__linux__) || defined(__gnu_linux__) || defined(_UNIX03_SOURCE)
-  sched_yield();
-#elif (defined(_GNU_SOURCE) && __GLIBC_PREREQ(2, 1)) || defined(_OPEN_THREADS)
-  pthread_yield();
-#endif
-}
-
-#if MDBX_64BIT_CAS
-static __always_inline bool atomic_cas64(MDBX_atomic_uint64_t *p, uint64_t c,
-                                         uint64_t v) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  STATIC_ASSERT(sizeof(long long) >= sizeof(uint64_t));
-#ifdef ATOMIC_LLONG_LOCK_FREE
-  STATIC_ASSERT(ATOMIC_LLONG_LOCK_FREE > 0);
-#if ATOMIC_LLONG_LOCK_FREE < 2
-  assert(atomic_is_lock_free(&p->c11a));
-#endif /* ATOMIC_LLONG_LOCK_FREE < 2 */
-#else  /* defined(ATOMIC_LLONG_LOCK_FREE) */
-  assert(atomic_is_lock_free(&p->c11a));
-#endif
-  return atomic_compare_exchange_strong(&p->c11a, &c, v);
-#elif defined(__GNUC__) || defined(__clang__)
-  return __sync_bool_compare_and_swap(&p->weak, c, v);
-#elif defined(_MSC_VER)
-  return c == (uint64_t)_InterlockedCompareExchange64(&p->weak, v, c);
-#elif defined(__APPLE__)
-  return OSAtomicCompareAndSwap64Barrier(c, v, &p->weak);
-#else
-#error FIXME: Unsupported compiler
-#endif
-}
-#endif /* MDBX_64BIT_CAS */
-
-static __always_inline bool atomic_cas32(MDBX_atomic_uint32_t *p, uint32_t c,
-                                         uint32_t v) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  STATIC_ASSERT(sizeof(int) >= sizeof(uint32_t));
-#ifdef ATOMIC_INT_LOCK_FREE
-  STATIC_ASSERT(ATOMIC_INT_LOCK_FREE > 0);
-#if ATOMIC_INT_LOCK_FREE < 2
-  assert(atomic_is_lock_free(&p->c11a));
-#endif
-#else
-  assert(atomic_is_lock_free(&p->c11a));
-#endif
-  return atomic_compare_exchange_strong(&p->c11a, &c, v);
-#elif defined(__GNUC__) || defined(__clang__)
-  return __sync_bool_compare_and_swap(&p->weak, c, v);
-#elif defined(_MSC_VER)
-  STATIC_ASSERT(sizeof(volatile long) == sizeof(volatile uint32_t));
-  return c == (uint32_t)_InterlockedCompareExchange(&p->weak, v, c);
-#elif defined(__APPLE__)
-  return OSAtomicCompareAndSwap32Barrier(c, v, &p->weak);
-#else
-#error FIXME: Unsupported compiler
-#endif
-}
-
-static __always_inline uint32_t atomic_add32(MDBX_atomic_uint32_t *p,
-                                             uint32_t v) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  STATIC_ASSERT(sizeof(int) >= sizeof(uint32_t));
-#ifdef ATOMIC_INT_LOCK_FREE
-  STATIC_ASSERT(ATOMIC_INT_LOCK_FREE > 0);
-#if ATOMIC_INT_LOCK_FREE < 2
-  assert(atomic_is_lock_free(&p->c11a));
-#endif
-#else
-  assert(atomic_is_lock_free(&p->c11a));
-#endif
-  return atomic_fetch_add(&p->c11a, v);
-#elif defined(__GNUC__) || defined(__clang__)
-  return __sync_fetch_and_add(&p->weak, v);
-#elif defined(_MSC_VER)
-  STATIC_ASSERT(sizeof(volatile long) == sizeof(volatile uint32_t));
-  return _InterlockedExchangeAdd(&p->weak, v);
-#elif defined(__APPLE__)
-  return OSAtomicAdd32Barrier(v, &p->weak);
-#else
-#error FIXME: Unsupported compiler
-#endif
-}
-
-#define atomic_sub32(p, v) atomic_add32(p, 0 - (v))
-
-static __always_inline uint64_t safe64_txnid_next(uint64_t txnid) {
-  txnid += MDBX_TXNID_STEP;
-#if !MDBX_64BIT_CAS
-  /* avoid overflow of low-part in safe64_reset() */
-  txnid += (UINT32_MAX == (uint32_t)txnid);
-#endif
-  return txnid;
-}
-
-static __always_inline void safe64_reset(MDBX_atomic_uint64_t *ptr,
-                                         bool single_writer) {
-#if !MDBX_64BIT_CAS
-  if (!single_writer) {
-    STATIC_ASSERT(MDBX_TXNID_STEP > 1);
-    /* it is safe to increment low-part to avoid ABA, since MDBX_TXNID_STEP > 1
-     * and overflow was preserved in safe64_txnid_next() */
-    atomic_add32(&ptr->low, 1) /* avoid ABA in safe64_reset_compare() */;
-    atomic_store32(
-        &ptr->high, UINT32_MAX,
-        mo_AcquireRelease) /* atomically make >= SAFE64_INVALID_THRESHOLD */;
-    atomic_add32(&ptr->low, 1) /* avoid ABA in safe64_reset_compare() */;
-  } else
-#elif MDBX_64BIT_ATOMIC
-  /* atomically make value >= SAFE64_INVALID_THRESHOLD by 64-bit operation */
-  atomic_store64(ptr, UINT64_MAX,
-                 single_writer ? mo_AcquireRelease : mo_SequentialConsistency);
-#else
-  /* atomically make value >= SAFE64_INVALID_THRESHOLD by 32-bit operation */
-  atomic_store32(&ptr->high, UINT32_MAX,
-                 single_writer ? mo_AcquireRelease : mo_SequentialConsistency);
-#endif /* MDBX_64BIT_ATOMIC */
-    assert(ptr->weak >= SAFE64_INVALID_THRESHOLD);
-  mdbx_jitter4testing(true);
-}
-
-static __always_inline bool safe64_reset_compare(MDBX_atomic_uint64_t *ptr,
-                                                 txnid_t compare) {
-  /* LY: This function is used to reset `mr_txnid` from hsr-handler in case
-   *     the asynchronously cancellation of read transaction. Therefore,
-   *     there may be a collision between the cleanup performed here and
-   *     asynchronous termination and restarting of the read transaction
-   *     in another proces/thread. In general we MUST NOT reset the `mr_txnid`
-   *     if a new transaction was started (i.e. if `mr_txnid` was changed). */
-#if MDBX_64BIT_CAS
-  bool rc = atomic_cas64(ptr, compare, UINT64_MAX);
-#else
-  /* LY: There is no gold ratio here since shared mutex is too costly,
-   *     in such way we must acquire/release it for every update of mr_txnid,
-   *     i.e. twice for each read transaction). */
-  bool rc = false;
-  if (likely(atomic_load32(&ptr->low, mo_AcquireRelease) == (uint32_t)compare &&
-             atomic_cas32(&ptr->high, (uint32_t)(compare >> 32), UINT32_MAX))) {
-    if (unlikely(atomic_load32(&ptr->low, mo_AcquireRelease) !=
-                 (uint32_t)compare))
-      atomic_cas32(&ptr->high, UINT32_MAX, (uint32_t)(compare >> 32));
-    else
-      rc = true;
-  }
-#endif /* MDBX_64BIT_CAS */
-  mdbx_jitter4testing(true);
-  return rc;
-}
-
-static __always_inline void safe64_write(MDBX_atomic_uint64_t *ptr,
-                                         const uint64_t v) {
-  assert(ptr->weak >= SAFE64_INVALID_THRESHOLD);
-#if MDBX_64BIT_ATOMIC
-  atomic_store64(ptr, v, mo_AcquireRelease);
-#else  /* MDBX_64BIT_ATOMIC */
-  /* update low-part but still value >= SAFE64_INVALID_THRESHOLD */
-  atomic_store32(&ptr->low, (uint32_t)v, mo_AcquireRelease);
-  assert(ptr->weak >= SAFE64_INVALID_THRESHOLD);
-  mdbx_jitter4testing(true);
-  /* update high-part from SAFE64_INVALID_THRESHOLD to actual value */
-  atomic_store32(&ptr->high, (uint32_t)(v >> 32), mo_AcquireRelease);
-#endif /* MDBX_64BIT_ATOMIC */
-  assert(ptr->weak == v);
-  mdbx_jitter4testing(true);
-}
-
-static __always_inline uint64_t safe64_read(const MDBX_atomic_uint64_t *ptr) {
-  mdbx_jitter4testing(true);
-  uint64_t v = atomic_load64(ptr, mo_AcquireRelease);
-  mdbx_jitter4testing(true);
-  return v;
-}
-
-#if 0 /* unused for now */
- static __maybe_unused __always_inline bool safe64_is_valid(uint64_t v) {
-#if MDBX_WORDBITS >= 64
-  return v < SAFE64_INVALID_THRESHOLD;
-#else
-  return (v >> 32) != UINT32_MAX;
-#endif /* MDBX_WORDBITS */
-}
-
- static __maybe_unused __always_inline bool
- safe64_is_valid_ptr(const MDBX_atomic_uint64_t *ptr) {
-#if MDBX_64BIT_ATOMIC
-  return atomic_load64(ptr, mo_AcquireRelease) < SAFE64_INVALID_THRESHOLD;
-#else
-  return atomic_load32(&ptr->high, mo_AcquireRelease) != UINT32_MAX;
-#endif /* MDBX_64BIT_ATOMIC */
-}
-
-static __always_inline void safe64_update(MDBX_atomic_uint64_t *ptr,
-                                          const uint64_t v) {
-#if MDBX_64BIT_ATOMIC
-  safe64_reset(ptr, true);
-#endif /* MDBX_64BIT_ATOMIC */
-  safe64_write(ptr, v);
-}
-#endif /* unused for now */
-
-/*----------------------------------------------------------------------------*/
-/* rthc (tls keys and destructors) */
-
-typedef struct rthc_entry_t {
-  MDBX_reader *begin;
-  MDBX_reader *end;
-  mdbx_thread_key_t thr_tls_key;
-  bool key_valid;
-} rthc_entry_t;
-
-#if MDBX_DEBUG
-#define RTHC_INITIAL_LIMIT 1
-#else
-#define RTHC_INITIAL_LIMIT 16
-#endif
-
-static bin128_t bootid;
-
-#if defined(_WIN32) || defined(_WIN64)
-static CRITICAL_SECTION rthc_critical_section;
-static CRITICAL_SECTION lcklist_critical_section;
-#else
-int __cxa_thread_atexit_impl(void (*dtor)(void *), void *obj, void *dso_symbol)
-    __attribute__((__weak__));
-#ifdef __APPLE__ /* FIXME: Thread-Local Storage destructors & DSO-unloading */
-int __cxa_thread_atexit_impl(void (*dtor)(void *), void *obj,
-                             void *dso_symbol) {
-  (void)dtor;
-  (void)obj;
-  (void)dso_symbol;
-  return -1;
-}
-#endif           /* __APPLE__ */
-
-static pthread_mutex_t lcklist_mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_mutex_t rthc_mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t rthc_cond = PTHREAD_COND_INITIALIZER;
-static mdbx_thread_key_t rthc_key;
-static MDBX_atomic_uint32_t rthc_pending;
-
-static void __cold workaround_glibc_bug21031(void) {
-  /* Workaround for https://sourceware.org/bugzilla/show_bug.cgi?id=21031
-   *
-   * Due race between pthread_key_delete() and __nptl_deallocate_tsd()
-   * The destructor(s) of thread-local-storage object(s) may be running
-   * in another thread(s) and be blocked or not finished yet.
-   * In such case we get a SEGFAULT after unload this library DSO.
-   *
-   * So just by yielding a few timeslices we give a chance
-   * to such destructor(s) for completion and avoids segfault. */
-  sched_yield();
-  sched_yield();
-  sched_yield();
-}
-#endif
-
-static unsigned rthc_count, rthc_limit;
-static rthc_entry_t *rthc_table;
-static rthc_entry_t rthc_table_static[RTHC_INITIAL_LIMIT];
-
-static __inline void rthc_lock(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  EnterCriticalSection(&rthc_critical_section);
-#else
-  mdbx_ensure(nullptr, pthread_mutex_lock(&rthc_mutex) == 0);
-#endif
-}
-
-static __inline void rthc_unlock(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  LeaveCriticalSection(&rthc_critical_section);
-#else
-  mdbx_ensure(nullptr, pthread_mutex_unlock(&rthc_mutex) == 0);
-#endif
-}
-
-static __inline int thread_key_create(mdbx_thread_key_t *key) {
-  int rc;
-#if defined(_WIN32) || defined(_WIN64)
-  *key = TlsAlloc();
-  rc = (*key != TLS_OUT_OF_INDEXES) ? MDBX_SUCCESS : GetLastError();
-#else
-  rc = pthread_key_create(key, nullptr);
-#endif
-  mdbx_trace("&key = %p, value %" PRIuPTR ", rc %d",
-             __Wpedantic_format_voidptr(key), (uintptr_t)*key, rc);
-  return rc;
-}
-
-static __inline void thread_key_delete(mdbx_thread_key_t key) {
-  mdbx_trace("key = %" PRIuPTR, (uintptr_t)key);
-#if defined(_WIN32) || defined(_WIN64)
-  mdbx_ensure(nullptr, TlsFree(key));
-#else
-  mdbx_ensure(nullptr, pthread_key_delete(key) == 0);
-  workaround_glibc_bug21031();
-#endif
-}
-
-static __inline void *thread_rthc_get(mdbx_thread_key_t key) {
-#if defined(_WIN32) || defined(_WIN64)
-  return TlsGetValue(key);
-#else
-  return pthread_getspecific(key);
-#endif
-}
-
-static void thread_rthc_set(mdbx_thread_key_t key, const void *value) {
-#if defined(_WIN32) || defined(_WIN64)
-  mdbx_ensure(nullptr, TlsSetValue(key, (void *)value));
-#else
-#define MDBX_THREAD_RTHC_ZERO 0
-#define MDBX_THREAD_RTHC_REGISTERED 1
-#define MDBX_THREAD_RTHC_COUNTED 2
-  static __thread uint32_t thread_registration_state;
-  if (value && unlikely(thread_registration_state == MDBX_THREAD_RTHC_ZERO)) {
-    thread_registration_state = MDBX_THREAD_RTHC_REGISTERED;
-    mdbx_trace("thread registered 0x%" PRIxPTR, mdbx_thread_self());
-    if (&__cxa_thread_atexit_impl == nullptr ||
-        __cxa_thread_atexit_impl(mdbx_rthc_thread_dtor,
-                                 &thread_registration_state,
-                                 (void *)&mdbx_version /* dso_anchor */)) {
-      mdbx_ensure(nullptr, pthread_setspecific(
-                               rthc_key, &thread_registration_state) == 0);
-      thread_registration_state = MDBX_THREAD_RTHC_COUNTED;
-      const unsigned count_before = atomic_add32(&rthc_pending, 1);
-      mdbx_ensure(nullptr, count_before < INT_MAX);
-      mdbx_trace("fallback to pthreads' tsd, key %" PRIuPTR ", count %u",
-                 (uintptr_t)rthc_key, count_before);
-      (void)count_before;
-    }
-  }
-  mdbx_ensure(nullptr, pthread_setspecific(key, value) == 0);
-#endif
-}
-
-__cold void mdbx_rthc_global_init(void) {
-  rthc_limit = RTHC_INITIAL_LIMIT;
-  rthc_table = rthc_table_static;
-#if defined(_WIN32) || defined(_WIN64)
-  InitializeCriticalSection(&rthc_critical_section);
-  InitializeCriticalSection(&lcklist_critical_section);
-#else
-  mdbx_ensure(nullptr,
-              pthread_key_create(&rthc_key, mdbx_rthc_thread_dtor) == 0);
-  mdbx_trace("pid %d, &mdbx_rthc_key = %p, value 0x%x", mdbx_getpid(),
-             __Wpedantic_format_voidptr(&rthc_key), (unsigned)rthc_key);
-#endif
-  /* checking time conversion, this also avoids racing on 32-bit architectures
-   * during writing calculated 64-bit ratio(s) into memory. */
-  uint32_t proba = UINT32_MAX;
-  while (true) {
-    unsigned time_conversion_checkup =
-        mdbx_osal_monotime_to_16dot16(mdbx_osal_16dot16_to_monotime(proba));
-    unsigned one_more = (proba < UINT32_MAX) ? proba + 1 : proba;
-    unsigned one_less = (proba > 0) ? proba - 1 : proba;
-    mdbx_ensure(nullptr, time_conversion_checkup >= one_less &&
-                             time_conversion_checkup <= one_more);
-    if (proba == 0)
-      break;
-    proba >>= 1;
-  }
-
-  bootid = mdbx_osal_bootid();
-}
-
-/* dtor called for thread, i.e. for all mdbx's environment objects */
-__cold void mdbx_rthc_thread_dtor(void *ptr) {
-  rthc_lock();
-  mdbx_trace(">> pid %d, thread 0x%" PRIxPTR ", rthc %p", mdbx_getpid(),
-             mdbx_thread_self(), ptr);
-
-  const uint32_t self_pid = mdbx_getpid();
-  for (unsigned i = 0; i < rthc_count; ++i) {
-    if (!rthc_table[i].key_valid)
-      continue;
-    const mdbx_thread_key_t key = rthc_table[i].thr_tls_key;
-    MDBX_reader *const rthc = thread_rthc_get(key);
-    if (rthc < rthc_table[i].begin || rthc >= rthc_table[i].end)
-      continue;
-#if !defined(_WIN32) && !defined(_WIN64)
-    if (pthread_setspecific(key, nullptr) != 0) {
-      mdbx_trace("== thread 0x%" PRIxPTR
-                 ", rthc %p: ignore race with tsd-key deletion",
-                 mdbx_thread_self(), ptr);
-      continue /* ignore race with tsd-key deletion by mdbx_env_close() */;
-    }
-#endif
-
-    mdbx_trace("== thread 0x%" PRIxPTR
-               ", rthc %p, [%i], %p ... %p (%+i), rtch-pid %i, "
-               "current-pid %i",
-               mdbx_thread_self(), __Wpedantic_format_voidptr(rthc), i,
-               __Wpedantic_format_voidptr(rthc_table[i].begin),
-               __Wpedantic_format_voidptr(rthc_table[i].end),
-               (int)(rthc - rthc_table[i].begin), rthc->mr_pid.weak, self_pid);
-    if (atomic_load32(&rthc->mr_pid, mo_Relaxed) == self_pid) {
-      mdbx_trace("==== thread 0x%" PRIxPTR ", rthc %p, cleanup",
-                 mdbx_thread_self(), __Wpedantic_format_voidptr(rthc));
-      atomic_store32(&rthc->mr_pid, 0, mo_AcquireRelease);
-    }
-  }
-
-#if defined(_WIN32) || defined(_WIN64)
-  mdbx_trace("<< thread 0x%" PRIxPTR ", rthc %p", mdbx_thread_self(), ptr);
-  rthc_unlock();
-#else
-  const char self_registration = *(char *)ptr;
-  *(char *)ptr = MDBX_THREAD_RTHC_ZERO;
-  mdbx_trace("== thread 0x%" PRIxPTR ", rthc %p, pid %d, self-status %d",
-             mdbx_thread_self(), ptr, mdbx_getpid(), self_registration);
-  if (self_registration == MDBX_THREAD_RTHC_COUNTED)
-    mdbx_ensure(nullptr, atomic_sub32(&rthc_pending, 1) > 0);
-
-  if (atomic_load32(&rthc_pending, mo_AcquireRelease) == 0) {
-    mdbx_trace("== thread 0x%" PRIxPTR ", rthc %p, pid %d, wake",
-               mdbx_thread_self(), ptr, mdbx_getpid());
-    mdbx_ensure(nullptr, pthread_cond_broadcast(&rthc_cond) == 0);
-  }
-
-  mdbx_trace("<< thread 0x%" PRIxPTR ", rthc %p", mdbx_thread_self(), ptr);
-  /* Allow tail call optimization, i.e. gcc should generate the jmp instruction
-   * instead of a call for pthread_mutex_unlock() and therefore CPU could not
-   * return to current DSO's code section, which may be unloaded immediately
-   * after the mutex got released. */
-  pthread_mutex_unlock(&rthc_mutex);
-#endif
-}
-
-__cold void mdbx_rthc_global_dtor(void) {
-  mdbx_trace(">> pid %d", mdbx_getpid());
-
-  rthc_lock();
-#if !defined(_WIN32) && !defined(_WIN64)
-  char *rthc = (char *)pthread_getspecific(rthc_key);
-  mdbx_trace("== thread 0x%" PRIxPTR ", rthc %p, pid %d, self-status %d",
-             mdbx_thread_self(), __Wpedantic_format_voidptr(rthc),
-             mdbx_getpid(), rthc ? *rthc : -1);
-  if (rthc) {
-    const char self_registration = *(char *)rthc;
-    *rthc = MDBX_THREAD_RTHC_ZERO;
-    if (self_registration == MDBX_THREAD_RTHC_COUNTED)
-      mdbx_ensure(nullptr, atomic_sub32(&rthc_pending, 1) > 0);
-  }
-
-  struct timespec abstime;
-  mdbx_ensure(nullptr, clock_gettime(CLOCK_REALTIME, &abstime) == 0);
-  abstime.tv_nsec += 1000000000l / 10;
-  if (abstime.tv_nsec >= 1000000000l) {
-    abstime.tv_nsec -= 1000000000l;
-    abstime.tv_sec += 1;
-  }
-#if MDBX_DEBUG > 0
-  abstime.tv_sec += 600;
-#endif
-
-  for (unsigned left;
-       (left = atomic_load32(&rthc_pending, mo_AcquireRelease)) > 0;) {
-    mdbx_trace("pid %d, pending %u, wait for...", mdbx_getpid(), left);
-    const int rc = pthread_cond_timedwait(&rthc_cond, &rthc_mutex, &abstime);
-    if (rc && rc != EINTR)
-      break;
-  }
-  thread_key_delete(rthc_key);
-#endif
-
-  const uint32_t self_pid = mdbx_getpid();
-  for (unsigned i = 0; i < rthc_count; ++i) {
-    if (!rthc_table[i].key_valid)
-      continue;
-    const mdbx_thread_key_t key = rthc_table[i].thr_tls_key;
-    thread_key_delete(key);
-    for (MDBX_reader *rthc = rthc_table[i].begin; rthc < rthc_table[i].end;
-         ++rthc) {
-      mdbx_trace(
-          "== [%i] = key %" PRIuPTR ", %p ... %p, rthc %p (%+i), "
-          "rthc-pid %i, current-pid %i",
-          i, (uintptr_t)key, __Wpedantic_format_voidptr(rthc_table[i].begin),
-          __Wpedantic_format_voidptr(rthc_table[i].end),
-          __Wpedantic_format_voidptr(rthc), (int)(rthc - rthc_table[i].begin),
-          rthc->mr_pid.weak, self_pid);
-      if (atomic_load32(&rthc->mr_pid, mo_Relaxed) == self_pid) {
-        atomic_store32(&rthc->mr_pid, 0, mo_AcquireRelease);
-        mdbx_trace("== cleanup %p", __Wpedantic_format_voidptr(rthc));
-      }
-    }
-  }
-
-  rthc_limit = rthc_count = 0;
-  if (rthc_table != rthc_table_static)
-    mdbx_free(rthc_table);
-  rthc_table = nullptr;
-  rthc_unlock();
-
-#if defined(_WIN32) || defined(_WIN64)
-  DeleteCriticalSection(&lcklist_critical_section);
-  DeleteCriticalSection(&rthc_critical_section);
-#else
-  /* LY: yielding a few timeslices to give a more chance
-   * to racing destructor(s) for completion. */
-  workaround_glibc_bug21031();
-#endif
-
-  mdbx_trace("<< pid %d\n", mdbx_getpid());
-}
-
-__cold int mdbx_rthc_alloc(mdbx_thread_key_t *key, MDBX_reader *begin,
-                           MDBX_reader *end) {
-  int rc;
-  if (key) {
-#ifndef NDEBUG
-    *key = (mdbx_thread_key_t)0xBADBADBAD;
-#endif /* NDEBUG */
-    rc = thread_key_create(key);
-    if (rc != MDBX_SUCCESS)
-      return rc;
-  }
-
-  rthc_lock();
-  const mdbx_thread_key_t new_key = key ? *key : 0;
-  mdbx_trace(">> key %" PRIuPTR ", rthc_count %u, rthc_limit %u",
-             (uintptr_t)new_key, rthc_count, rthc_limit);
-  if (rthc_count == rthc_limit) {
-    rthc_entry_t *new_table =
-        mdbx_realloc((rthc_table == rthc_table_static) ? nullptr : rthc_table,
-                     sizeof(rthc_entry_t) * rthc_limit * 2);
-    if (new_table == nullptr) {
-      rc = MDBX_ENOMEM;
-      goto bailout;
-    }
-    if (rthc_table == rthc_table_static)
-      memcpy(new_table, rthc_table_static, sizeof(rthc_table_static));
-    rthc_table = new_table;
-    rthc_limit *= 2;
-  }
-  mdbx_trace("== [%i] = key %" PRIuPTR ", %p ... %p", rthc_count,
-             (uintptr_t)new_key, __Wpedantic_format_voidptr(begin),
-             __Wpedantic_format_voidptr(end));
-  rthc_table[rthc_count].key_valid = key ? true : false;
-  rthc_table[rthc_count].thr_tls_key = key ? new_key : 0;
-  rthc_table[rthc_count].begin = begin;
-  rthc_table[rthc_count].end = end;
-  ++rthc_count;
-  mdbx_trace("<< key %" PRIuPTR ", rthc_count %u, rthc_limit %u",
-             (uintptr_t)new_key, rthc_count, rthc_limit);
-  rthc_unlock();
-  return MDBX_SUCCESS;
-
-bailout:
-  if (key)
-    thread_key_delete(*key);
-  rthc_unlock();
-  return rc;
-}
-
-__cold void mdbx_rthc_remove(const mdbx_thread_key_t key) {
-  thread_key_delete(key);
-  rthc_lock();
-  mdbx_trace(">> key %zu, rthc_count %u, rthc_limit %u", (size_t)key,
-             rthc_count, rthc_limit);
-
-  for (unsigned i = 0; i < rthc_count; ++i) {
-    if (rthc_table[i].key_valid && key == rthc_table[i].thr_tls_key) {
-      const uint32_t self_pid = mdbx_getpid();
-      mdbx_trace("== [%i], %p ...%p, current-pid %d", i,
-                 __Wpedantic_format_voidptr(rthc_table[i].begin),
-                 __Wpedantic_format_voidptr(rthc_table[i].end), self_pid);
-
-      for (MDBX_reader *rthc = rthc_table[i].begin; rthc < rthc_table[i].end;
-           ++rthc) {
-        if (atomic_load32(&rthc->mr_pid, mo_Relaxed) == self_pid) {
-          atomic_store32(&rthc->mr_pid, 0, mo_AcquireRelease);
-          mdbx_trace("== cleanup %p", __Wpedantic_format_voidptr(rthc));
-        }
-      }
-      if (--rthc_count > 0)
-        rthc_table[i] = rthc_table[rthc_count];
-      else if (rthc_table != rthc_table_static) {
-        mdbx_free(rthc_table);
-        rthc_table = rthc_table_static;
-        rthc_limit = RTHC_INITIAL_LIMIT;
-      }
-      break;
-    }
-  }
-
-  mdbx_trace("<< key %zu, rthc_count %u, rthc_limit %u", (size_t)key,
-             rthc_count, rthc_limit);
-  rthc_unlock();
-}
-
-//------------------------------------------------------------------------------
-
-#define RTHC_ENVLIST_END ((MDBX_env *)((uintptr_t)50459))
-static MDBX_env *inprocess_lcklist_head = RTHC_ENVLIST_END;
-
-static __inline void lcklist_lock(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  EnterCriticalSection(&lcklist_critical_section);
-#else
-  mdbx_ensure(nullptr, pthread_mutex_lock(&lcklist_mutex) == 0);
-#endif
-}
-
-static __inline void lcklist_unlock(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  LeaveCriticalSection(&lcklist_critical_section);
-#else
-  mdbx_ensure(nullptr, pthread_mutex_unlock(&lcklist_mutex) == 0);
-#endif
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static uint64_t rrxmrrxmsx_0(uint64_t v) {
-  /* Pelle Evensen's mixer, https://bit.ly/2HOfynt */
-  v ^= (v << 39 | v >> 25) ^ (v << 14 | v >> 50);
-  v *= UINT64_C(0xA24BAED4963EE407);
-  v ^= (v << 40 | v >> 24) ^ (v << 15 | v >> 49);
-  v *= UINT64_C(0x9FB21C651E98DF25);
-  return v ^ v >> 28;
-}
-
-static int uniq_peek(const mdbx_mmap_t *pending, mdbx_mmap_t *scan) {
-  int rc;
-  uint64_t bait;
-  if (pending->address) {
-    bait = atomic_load64(&pending->lck->mti_bait_uniqueness, mo_AcquireRelease);
-    rc = MDBX_SUCCESS;
-  } else {
-    bait = 0 /* hush MSVC warning */;
-    rc = mdbx_msync(scan, 0, sizeof(MDBX_lockinfo), true);
-    if (rc == MDBX_SUCCESS)
-      rc =
-          mdbx_pread(pending->fd, &bait, sizeof(scan->lck->mti_bait_uniqueness),
-                     offsetof(MDBX_lockinfo, mti_bait_uniqueness));
-  }
-  if (likely(rc == MDBX_SUCCESS) &&
-      bait == atomic_load64(&scan->lck->mti_bait_uniqueness, mo_AcquireRelease))
-    rc = MDBX_RESULT_TRUE;
-
-  mdbx_trace("uniq-peek: %s, bait 0x%016" PRIx64 ",%s rc %d",
-             pending->lck ? "mem" : "file", bait,
-             (rc == MDBX_RESULT_TRUE) ? " found," : (rc ? " FAILED," : ""), rc);
-  return rc;
-}
-
-static int uniq_poke(const mdbx_mmap_t *pending, mdbx_mmap_t *scan,
-                     uint64_t *abra) {
-  if (*abra == 0) {
-    const uintptr_t tid = mdbx_thread_self();
-    uintptr_t uit = 0;
-    memcpy(&uit, &tid, (sizeof(tid) < sizeof(uit)) ? sizeof(tid) : sizeof(uit));
-    *abra =
-        rrxmrrxmsx_0(mdbx_osal_monotime() + UINT64_C(5873865991930747) * uit);
-  }
-  const uint64_t cadabra =
-      rrxmrrxmsx_0(*abra + UINT64_C(7680760450171793) * (unsigned)mdbx_getpid())
-          << 24 |
-      *abra >> 40;
-  atomic_store64(&scan->lck->mti_bait_uniqueness, cadabra,
-                 mo_SequentialConsistency);
-  *abra = *abra * UINT64_C(6364136223846793005) + 1;
-  return uniq_peek(pending, scan);
-}
-
-__cold static int uniq_check(const mdbx_mmap_t *pending, MDBX_env **found) {
-  *found = nullptr;
-  uint64_t salt = 0;
-  for (MDBX_env *scan = inprocess_lcklist_head; scan != RTHC_ENVLIST_END;
-       scan = scan->me_lcklist_next) {
-    int err = atomic_load64(&scan->me_lck_mmap.lck->mti_bait_uniqueness,
-                            mo_AcquireRelease)
-                  ? uniq_peek(pending, &scan->me_lck_mmap)
-                  : uniq_poke(pending, &scan->me_lck_mmap, &salt);
-    if (err == MDBX_ENODATA) {
-      uint64_t length;
-      if (likely(mdbx_filesize(pending->fd, &length) == MDBX_SUCCESS &&
-                 length == 0)) {
-        /* LY: skip checking since LCK-file is empty, i.e. just created. */
-        mdbx_debug("uniq-probe: %s", "unique (new/empty lck)");
-        return MDBX_RESULT_TRUE;
-      }
-    }
-    if (err == MDBX_RESULT_TRUE)
-      err = uniq_poke(pending, &scan->me_lck_mmap, &salt);
-    if (err == MDBX_RESULT_TRUE) {
-      (void)mdbx_msync(&scan->me_lck_mmap, 0, sizeof(MDBX_lockinfo), false);
-      err = uniq_poke(pending, &scan->me_lck_mmap, &salt);
-    }
-    if (err == MDBX_RESULT_TRUE) {
-      err = uniq_poke(pending, &scan->me_lck_mmap, &salt);
-      *found = scan;
-      mdbx_debug("uniq-probe: found %p", __Wpedantic_format_voidptr(*found));
-      return MDBX_RESULT_FALSE;
-    }
-    if (unlikely(err != MDBX_SUCCESS)) {
-      mdbx_debug("uniq-probe: failed rc %d", err);
-      return err;
-    }
-  }
-
-  mdbx_debug("uniq-probe: %s", "unique");
-  return MDBX_RESULT_TRUE;
-}
-
-static int lcklist_detach_locked(MDBX_env *env) {
-  MDBX_env *inprocess_neighbor = nullptr;
-  int rc = MDBX_SUCCESS;
-  if (env->me_lcklist_next != nullptr) {
-    mdbx_ensure(env, env->me_lcklist_next != nullptr);
-    mdbx_ensure(env, inprocess_lcklist_head != RTHC_ENVLIST_END);
-    for (MDBX_env **ptr = &inprocess_lcklist_head; *ptr != RTHC_ENVLIST_END;
-         ptr = &(*ptr)->me_lcklist_next) {
-      if (*ptr == env) {
-        *ptr = env->me_lcklist_next;
-        env->me_lcklist_next = nullptr;
-        break;
-      }
-    }
-    mdbx_ensure(env, env->me_lcklist_next == nullptr);
-  }
-
-  rc = likely(mdbx_getpid() == env->me_pid)
-           ? uniq_check(&env->me_lck_mmap, &inprocess_neighbor)
-           : MDBX_PANIC;
-  if (!inprocess_neighbor && env->me_live_reader)
-    (void)mdbx_rpid_clear(env);
-  if (!MDBX_IS_ERROR(rc))
-    rc = mdbx_lck_destroy(env, inprocess_neighbor);
-  return rc;
-}
-
-/*------------------------------------------------------------------------------
- * LY: State of the art quicksort-based sorting, with internal stack
- * and network-sort for small chunks.
- * Thanks to John M. Gamble for the http://pages.ripco.net/~jgamble/nw.html */
-
-#define SORT_CMP_SWAP(TYPE, CMP, a, b)                                         \
-  do {                                                                         \
-    const TYPE swap_tmp = (a);                                                 \
-    const bool swap_cmp = CMP(swap_tmp, b);                                    \
-    (a) = swap_cmp ? swap_tmp : b;                                             \
-    (b) = swap_cmp ? b : swap_tmp;                                             \
-  } while (0)
-
-//  3 comparators, 3 parallel operations
-//  o-----^--^--o
-//        |  |
-//  o--^--|--v--o
-//     |  |
-//  o--v--v-----o
-//
-//  [[1,2]]
-//  [[0,2]]
-//  [[0,1]]
-#define SORT_NETWORK_3(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-  } while (0)
-
-//  5 comparators, 3 parallel operations
-//  o--^--^--------o
-//     |  |
-//  o--v--|--^--^--o
-//        |  |  |
-//  o--^--v--|--v--o
-//     |     |
-//  o--v-----v-----o
-//
-//  [[0,1],[2,3]]
-//  [[0,2],[1,3]]
-//  [[1,2]]
-#define SORT_NETWORK_4(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-  } while (0)
-
-//  9 comparators, 5 parallel operations
-//  o--^--^-----^-----------o
-//     |  |     |
-//  o--|--|--^--v-----^--^--o
-//     |  |  |        |  |
-//  o--|--v--|--^--^--|--v--o
-//     |     |  |  |  |
-//  o--|-----v--|--v--|--^--o
-//     |        |     |  |
-//  o--v--------v-----v--v--o
-//
-//  [[0,4],[1,3]]
-//  [[0,2]]
-//  [[2,4],[0,1]]
-//  [[2,3],[1,4]]
-//  [[1,2],[3,4]]
-#define SORT_NETWORK_5(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-  } while (0)
-
-//  12 comparators, 6 parallel operations
-//  o-----^--^--^-----------------o
-//        |  |  |
-//  o--^--|--v--|--^--------^-----o
-//     |  |     |  |        |
-//  o--v--v-----|--|--^--^--|--^--o
-//              |  |  |  |  |  |
-//  o-----^--^--v--|--|--|--v--v--o
-//        |  |     |  |  |
-//  o--^--|--v-----v--|--v--------o
-//     |  |           |
-//  o--v--v-----------v-----------o
-//
-//  [[1,2],[4,5]]
-//  [[0,2],[3,5]]
-//  [[0,1],[3,4],[2,5]]
-//  [[0,3],[1,4]]
-//  [[2,4],[1,3]]
-//  [[2,3]]
-#define SORT_NETWORK_6(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-  } while (0)
-
-//  16 comparators, 6 parallel operations
-//  o--^--------^-----^-----------------o
-//     |        |     |
-//  o--|--^-----|--^--v--------^--^-----o
-//     |  |     |  |           |  |
-//  o--|--|--^--v--|--^-----^--|--v-----o
-//     |  |  |     |  |     |  |
-//  o--|--|--|-----v--|--^--v--|--^--^--o
-//     |  |  |        |  |     |  |  |
-//  o--v--|--|--^-----v--|--^--v--|--v--o
-//        |  |  |        |  |     |
-//  o-----v--|--|--------v--v-----|--^--o
-//           |  |                 |  |
-//  o--------v--v-----------------v--v--o
-//
-//  [[0,4],[1,5],[2,6]]
-//  [[0,2],[1,3],[4,6]]
-//  [[2,4],[3,5],[0,1]]
-//  [[2,3],[4,5]]
-//  [[1,4],[3,6]]
-//  [[1,2],[3,4],[5,6]]
-#define SORT_NETWORK_7(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-  } while (0)
-
-//  19 comparators, 6 parallel operations
-//  o--^--------^-----^-----------------o
-//     |        |     |
-//  o--|--^-----|--^--v--------^--^-----o
-//     |  |     |  |           |  |
-//  o--|--|--^--v--|--^-----^--|--v-----o
-//     |  |  |     |  |     |  |
-//  o--|--|--|--^--v--|--^--v--|--^--^--o
-//     |  |  |  |     |  |     |  |  |
-//  o--v--|--|--|--^--v--|--^--v--|--v--o
-//        |  |  |  |     |  |     |
-//  o-----v--|--|--|--^--v--v-----|--^--o
-//           |  |  |  |           |  |
-//  o--------v--|--v--|--^--------v--v--o
-//              |     |  |
-//  o-----------v-----v--v--------------o
-//
-//  [[0,4],[1,5],[2,6],[3,7]]
-//  [[0,2],[1,3],[4,6],[5,7]]
-//  [[2,4],[3,5],[0,1],[6,7]]
-//  [[2,3],[4,5]]
-//  [[1,4],[3,6]]
-//  [[1,2],[3,4],[5,6]]
-#define SORT_NETWORK_8(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-  } while (0)
-
-//  25 comparators, 9 parallel operations
-//  o--^-----^--^-----^-----------------------------------o
-//     |     |  |     |
-//  o--v--^--v--|-----|--^-----^-----------^--------------o
-//        |     |     |  |     |           |
-//  o-----v-----|-----|--|-----|--^-----^--|--^-----^--^--o
-//              |     |  |     |  |     |  |  |     |  |
-//  o--^-----^--v--^--v--|-----|--|-----|--v--|-----|--v--o
-//     |     |     |     |     |  |     |     |     |
-//  o--v--^--v-----|-----v--^--v--|-----|-----|--^--v-----o
-//        |        |        |     |     |     |  |
-//  o-----v--------|--------|-----v--^--v--^--|--|--^-----o
-//                 |        |        |     |  |  |  |
-//  o--^-----^-----v--------|--------|-----|--v--v--v-----o
-//     |     |              |        |     |
-//  o--v--^--v--------------v--------|-----v--------------o
-//        |                          |
-//  o-----v--------------------------v--------------------o
-//
-//  [[0,1],[3,4],[6,7]]
-//  [[1,2],[4,5],[7,8]]
-//  [[0,1],[3,4],[6,7],[2,5]]
-//  [[0,3],[1,4],[5,8]]
-//  [[3,6],[4,7],[2,5]]
-//  [[0,3],[1,4],[5,7],[2,6]]
-//  [[1,3],[4,6]]
-//  [[2,4],[5,6]]
-//  [[2,3]]
-#define SORT_NETWORK_9(TYPE, CMP, begin)                                       \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-  } while (0)
-
-//  29 comparators, 9 parallel operations
-//  o--------------^-----^--^--^-----------------------o
-//                 |     |  |  |
-//  o-----------^--|--^--|--|--v--^--------^-----------o
-//              |  |  |  |  |     |        |
-//  o--------^--|--|--|--|--v--^--v-----^--|--^--------o
-//           |  |  |  |  |     |        |  |  |
-//  o-----^--|--|--|--|--v--^--|-----^--|--v--v--^-----o
-//        |  |  |  |  |     |  |     |  |        |
-//  o--^--|--|--|--|--v-----|--v--^--|--|--^-----v--^--o
-//     |  |  |  |  |        |     |  |  |  |        |
-//  o--|--|--|--|--v--^-----|--^--|--v--v--|-----^--v--o
-//     |  |  |  |     |     |  |  |        |     |
-//  o--|--|--|--v--^--|-----v--|--v--^-----|--^--v-----o
-//     |  |  |     |  |        |     |     |  |
-//  o--|--|--v-----|--|--^-----v--^--|-----v--v--------o
-//     |  |        |  |  |        |  |
-//  o--|--v--------|--v--|--^-----v--v-----------------o
-//     |           |     |  |
-//  o--v-----------v-----v--v--------------------------o
-//
-//  [[4,9],[3,8],[2,7],[1,6],[0,5]]
-//  [[1,4],[6,9],[0,3],[5,8]]
-//  [[0,2],[3,6],[7,9]]
-//  [[0,1],[2,4],[5,7],[8,9]]
-//  [[1,2],[4,6],[7,8],[3,5]]
-//  [[2,5],[6,8],[1,3],[4,7]]
-//  [[2,3],[6,7]]
-//  [[3,4],[5,6]]
-//  [[4,5]]
-#define SORT_NETWORK_10(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-  } while (0)
-
-//  35 comparators, 9 parallel operations
-//  o--^-----^-----------------^--------^--------------------o
-//     |     |                 |        |
-//  o--v--^--|--^--^--------^--|--------|--^-----------------o
-//        |  |  |  |        |  |        |  |
-//  o--^--|--v--v--|-----^--|--|--------|--|-----^--^--------o
-//     |  |        |     |  |  |        |  |     |  |
-//  o--v--v--------|-----|--|--|--^-----|--|--^--v--|--^--^--o
-//                 |     |  |  |  |     |  |  |     |  |  |
-//  o--^-----^-----|-----|--|--v--|--^--v--v--|-----v--|--v--o
-//     |     |     |     |  |     |  |        |        |
-//  o--v--^--|--^--v--^--|--v-----|--|--------|--------v--^--o
-//        |  |  |     |  |        |  |        |           |
-//  o--^--|--v--v--^--|--v--^-----|--|--------|--------^--v--o
-//     |  |        |  |     |     |  |        |        |
-//  o--v--v--------|--|-----|-----v--|--^-----|-----^--|--^--o
-//                 |  |     |        |  |     |     |  |  |
-//  o--^--^--------|--|-----|--------v--|-----v--^--|--v--v--o
-//     |  |        |  |     |           |        |  |
-//  o--v--|--^-----|--v-----|-----------|--------v--v--------o
-//        |  |     |        |           |
-//  o-----v--v-----v--------v-----------v--------------------o
-//
-//  [[0,1],[2,3],[4,5],[6,7],[8,9]]
-//  [[1,3],[5,7],[0,2],[4,6],[8,10]]
-//  [[1,2],[5,6],[9,10],[0,4],[3,7]]
-//  [[1,5],[6,10],[4,8]]
-//  [[5,9],[2,6],[0,4],[3,8]]
-//  [[1,5],[6,10],[2,3],[8,9]]
-//  [[1,4],[7,10],[3,5],[6,8]]
-//  [[2,4],[7,9],[5,6]]
-//  [[3,4],[7,8]]
-#define SORT_NETWORK_11(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-  } while (0)
-
-//  39 comparators, parallel operations
-//  o--^-----^-----------------^--------^--------------------o
-//     |     |                 |        |
-//  o--v--^--|--^--^--------^--|--------|--^-----------------o
-//        |  |  |  |        |  |        |  |
-//  o--^--|--v--v--|-----^--|--|--------|--|-----^--^--------o
-//     |  |        |     |  |  |        |  |     |  |
-//  o--v--v--------|-----|--|--|--^-----|--|--^--v--|--^--^--o
-//                 |     |  |  |  |     |  |  |     |  |  |
-//  o--^-----^-----|-----|--|--v--|--^--v--v--|-----v--|--v--o
-//     |     |     |     |  |     |  |        |        |
-//  o--v--^--|--^--v--^--|--v-----|--|--------|--------v--^--o
-//        |  |  |     |  |        |  |        |           |
-//  o--^--|--v--v--^--|--v--^-----|--|--------|--------^--v--o
-//     |  |        |  |     |     |  |        |        |
-//  o--v--v--------|--|-----|--^--v--|--^--^--|-----^--|--^--o
-//                 |  |     |  |     |  |  |  |     |  |  |
-//  o--^-----^-----|--|-----|--|-----v--|--|--v--^--|--v--v--o
-//     |     |     |  |     |  |        |  |     |  |
-//  o--v--^--|--^--|--v-----|--|--------|--|-----v--v--------o
-//        |  |  |  |        |  |        |  |
-//  o--^--|--v--v--v--------v--|--------|--v-----------------o
-//     |  |                    |        |
-//  o--v--v--------------------v--------v--------------------o
-//
-//  [[0,1],[2,3],[4,5],[6,7],[8,9],[10,11]]
-//  [[1,3],[5,7],[9,11],[0,2],[4,6],[8,10]]
-//  [[1,2],[5,6],[9,10],[0,4],[7,11]]
-//  [[1,5],[6,10],[3,7],[4,8]]
-//  [[5,9],[2,6],[0,4],[7,11],[3,8]]
-//  [[1,5],[6,10],[2,3],[8,9]]
-//  [[1,4],[7,10],[3,5],[6,8]]
-//  [[2,4],[7,9],[5,6]]
-//  [[3,4],[7,8]]
-#define SORT_NETWORK_12(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[11]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-  } while (0)
-
-//  45 comparators, 10 parallel operations
-//  o--------^--^-----^-----------------------------^-----------------o
-//           |  |     |                             |
-//  o--^-----|--v-----|-----^--------------^-----^--|-----^-----------o
-//     |     |        |     |              |     |  |     |
-//  o--|-----|--^--^--v-----|--------------|--^--|--|--^--v--^--------o
-//     |     |  |  |        |              |  |  |  |  |     |
-//  o--|--^--|--|--v-----^--|--------^-----|--|--v--|--|--^--v-----^--o
-//     |  |  |  |        |  |        |     |  |     |  |  |        |
-//  o--|--v--|--|--^-----|--v-----^--v-----|--|--^--|--|--|--^--^--v--o
-//     |     |  |  |     |        |        |  |  |  |  |  |  |  |
-//  o--|--^--|--|--|--^--|--------|-----^--|--|--|--v--v--v--|--v--^--o
-//     |  |  |  |  |  |  |        |     |  |  |  |           |     |
-//  o--|--|--|--v--v--|--|--^-----|--^--v--|--v--|--^--------v--^--v--o
-//     |  |  |        |  |  |     |  |     |     |  |           |
-//  o--v--|--|-----^--|--v--|--^--|--|-----v-----v--|--^--------v-----o
-//        |  |     |  |     |  |  |  |              |  |
-//  o-----v--|--^--|--|-----|--v--|--|--^-----^-----v--v--^-----------o
-//           |  |  |  |     |     |  |  |     |           |
-//  o--^-----|--|--|--v-----|-----v--|--v--^--|--^--------v-----------o
-//     |     |  |  |        |        |     |  |  |
-//  o--|-----|--|--|--^-----|--------v--^--|--v--v--------------------o
-//     |     |  |  |  |     |           |  |
-//  o--v-----|--v--|--v-----|--^--------v--v--------------------------o
-//           |     |        |  |
-//  o--------v-----v--------v--v--------------------------------------o
-//
-//  [[1,7],[9,11],[3,4],[5,8],[0,12],[2,6]]
-//  [[0,1],[2,3],[4,6],[8,11],[7,12],[5,9]]
-//  [[0,2],[3,7],[10,11],[1,4],[6,12]]
-//  [[7,8],[11,12],[4,9],[6,10]]
-//  [[3,4],[5,6],[8,9],[10,11],[1,7]]
-//  [[2,6],[9,11],[1,3],[4,7],[8,10],[0,5]]
-//  [[2,5],[6,8],[9,10]]
-//  [[1,2],[3,5],[7,8],[4,6]]
-//  [[2,3],[4,5],[6,7],[8,9]]
-//  [[3,4],[5,6]]
-#define SORT_NETWORK_13(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[11]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[11]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-  } while (0)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-//  51 comparators, 10 parallel operations
-//  o--^--^-----^-----------^-----------------------------------------------------------o
-//     |  |     |           |
-//  o--v--|--^--|--^--------|--^-----^-----------------------^--------------------------o
-//        |  |  |  |        |  |     |                       |
-//  o--^--v--|--|--|--^-----|--|--^--v-----------------------|--^--^--------------------o
-//     |     |  |  |  |     |  |  |                          |  |  |
-//  o--v-----v--|--|--|--^--|--|--|--^--------------^--------|--|--|--^--^--^-----------o
-//              |  |  |  |  |  |  |  |              |        |  |  |  |  |  |
-//  o--^--^-----v--|--|--|--|--|--|--|--^-----------|-----^--v--|--v--|--|--v-----------o
-//     |  |        |  |  |  |  |  |  |  |           |     |     |     |  |
-//  o--v--|--^-----v--|--|--|--|--|--|--|--^--^-----|-----|-----|--^--|--v-----^--------o
-//        |  |        |  |  |  |  |  |  |  |  |     |     |     |  |  |        |
-//  o--^--v--|--------v--|--|--|--|--|--|--|--|--^--|-----|-----|--v--|-----^--v-----^--o
-//     |     |           |  |  |  |  |  |  |  |  |  |     |     |     |     |        |
-//  o--v-----v-----------v--|--|--|--|--|--|--|--|--|--^--|--^--|-----|--^--|--^--^--v--o
-//                          |  |  |  |  |  |  |  |  |  |  |  |  |     |  |  |  |  |
-//  o--^--^-----^-----------v--|--|--|--|--|--|--|--|--|--v--|--v-----v--|--v--|--v--^--o
-//     |  |     |              |  |  |  |  |  |  |  |  |     |           |     |     |
-//  o--v--|--^--|--^-----------v--|--|--|--|--|--v--|--|-----|--^--------|-----v--^--v--o
-//        |  |  |  |              |  |  |  |  |     |  |     |  |        |        |
-//  o--^--v--|--|--|--------------v--|--|--|--v-----|--|-----|--v--------|--^-----v-----o
-//     |     |  |  |                 |  |  |        |  |     |           |  |
-//  o--v-----v--|--|-----------------v--|--|--------|--v-----|--^--------|--|--^--------o
-//              |  |                    |  |        |        |  |        |  |  |
-//  o--^--------v--|--------------------v--|--------v--------|--|--------v--v--v--------o
-//     |           |                       |                 |  |
-//  o--v-----------v-----------------------v-----------------v--v-----------------------o
-//
-//  [[0,1],[2,3],[4,5],[6,7],[8,9],[10,11],[12,13]]
-//  [[0,2],[4,6],[8,10],[1,3],[5,7],[9,11]]
-//  [[0,4],[8,12],[1,5],[9,13],[2,6],[3,7]]
-//  [[0,8],[1,9],[2,10],[3,11],[4,12],[5,13]]
-//  [[5,10],[6,9],[3,12],[7,11],[1,2],[4,8]]
-//  [[1,4],[7,13],[2,8],[5,6],[9,10]]
-//  [[2,4],[11,13],[3,8],[7,12]]
-//  [[6,8],[10,12],[3,5],[7,9]]
-//  [[3,4],[5,6],[7,8],[9,10],[11,12]]
-//  [[6,7],[8,9]]
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#define SORT_NETWORK_14(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[11]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[12], begin[13]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[13]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-  } while (0)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-//  56 comparators, 10 parallel operations
-//  o--^--^-----^-----------^--------------------------------------------------------------o
-//     |  |     |           |
-//  o--v--|--^--|--^--------|--^-----^--------------------------^--------------------------o
-//        |  |  |  |        |  |     |                          |
-//  o--^--v--|--|--|--^-----|--|--^--v--------------------------|--^--^--------------------o
-//     |     |  |  |  |     |  |  |                             |  |  |
-//  o--v-----v--|--|--|--^--|--|--|--^-----------------^--------|--|--|--^--^--^-----------o
-//              |  |  |  |  |  |  |  |                 |        |  |  |  |  |  |
-//  o--^--^-----v--|--|--|--|--|--|--|--^--------------|-----^--v--|--v--|--|--v-----------o
-//     |  |        |  |  |  |  |  |  |  |              |     |     |     |  |
-//  o--v--|--^-----v--|--|--|--|--|--|--|--^-----^-----|-----|-----|--^--|--v-----^--------o
-//        |  |        |  |  |  |  |  |  |  |     |     |     |     |  |  |        |
-//  o--^--v--|--------v--|--|--|--|--|--|--|--^--|--^--|-----|-----|--v--|-----^--v-----^--o
-//     |     |           |  |  |  |  |  |  |  |  |  |  |     |     |     |     |        |
-//  o--v-----v-----------v--|--|--|--|--|--|--|--|--|--|--^--|--^--|-----|--^--|--^--^--v--o
-//                          |  |  |  |  |  |  |  |  |  |  |  |  |  |     |  |  |  |  |
-//  o--^--^-----^-----------v--|--|--|--|--|--|--|--|--|--|--v--|--v-----v--|--v--|--v--^--o
-//     |  |     |              |  |  |  |  |  |  |  |  |  |     |           |     |     |
-//  o--v--|--^--|--^-----------v--|--|--|--|--|--|--v--|--|-----|--^--------|-----v--^--v--o
-//        |  |  |  |              |  |  |  |  |  |     |  |     |  |        |        |
-//  o--^--v--|--|--|--^-----------v--|--|--|--|--v-----|--|-----|--v--------|--^-----v-----o
-//     |     |  |  |  |              |  |  |  |        |  |     |           |  |
-//  o--v-----v--|--|--|--------------v--|--|--|--------|--v-----|--^--^-----|--|--^--------o
-//              |  |  |                 |  |  |        |        |  |  |     |  |  |
-//  o--^--^-----v--|--|-----------------v--|--|--------v--------|--|--|-----v--v--v--------o
-//     |  |        |  |                    |  |                 |  |  |
-//  o--v--|--------v--|--------------------v--|--^--------------v--|--v--------------------o
-//        |           |                       |  |                 |
-//  o-----v-----------v-----------------------v--v-----------------v-----------------------o
-//
-//  [[0,1],[2,3],[4,5],[6,7],[8,9],[10,11],[12,13]]
-//  [[0,2],[4,6],[8,10],[12,14],[1,3],[5,7],[9,11]]
-//  [[0,4],[8,12],[1,5],[9,13],[2,6],[10,14],[3,7]]
-//  [[0,8],[1,9],[2,10],[3,11],[4,12],[5,13],[6,14]]
-//  [[5,10],[6,9],[3,12],[13,14],[7,11],[1,2],[4,8]]
-//  [[1,4],[7,13],[2,8],[11,14],[5,6],[9,10]]
-//  [[2,4],[11,13],[3,8],[7,12]]
-//  [[6,8],[10,12],[3,5],[7,9]]
-//  [[3,4],[5,6],[7,8],[9,10],[11,12]]
-//  [[6,7],[8,9]]
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#define SORT_NETWORK_15(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[11]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[12], begin[13]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[12], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[14]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[13], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[13]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-  } while (0)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-//  60 comparators, 10 parallel operations
-//  o--^--^-----^-----------^-----------------------------------------------------------------o
-//     |  |     |           |
-//  o--v--|--^--|--^--------|--^-----^-----------------------------^--------------------------o
-//        |  |  |  |        |  |     |                             |
-//  o--^--v--|--|--|--^-----|--|--^--v-----------------------------|--^--^--------------------o
-//     |     |  |  |  |     |  |  |                                |  |  |
-//  o--v-----v--|--|--|--^--|--|--|--^--------------------^--------|--|--|--^--^--^-----------o
-//              |  |  |  |  |  |  |  |                    |        |  |  |  |  |  |
-//  o--^--^-----v--|--|--|--|--|--|--|--^-----------------|-----^--v--|--v--|--|--v-----------o
-//     |  |        |  |  |  |  |  |  |  |                 |     |     |     |  |
-//  o--v--|--^-----v--|--|--|--|--|--|--|--^--------^-----|-----|-----|--^--|--v-----^--------o
-//        |  |        |  |  |  |  |  |  |  |        |     |     |     |  |  |        |
-//  o--^--v--|--------v--|--|--|--|--|--|--|--^-----|--^--|-----|-----|--v--|-----^--v-----^--o
-//     |     |           |  |  |  |  |  |  |  |     |  |  |     |     |     |     |        |
-//  o--v-----v-----------v--|--|--|--|--|--|--|--^--|--|--|--^--|--^--|-----|--^--|--^--^--v--o
-//                          |  |  |  |  |  |  |  |  |  |  |  |  |  |  |     |  |  |  |  |
-//  o--^--^-----^-----------v--|--|--|--|--|--|--|--|--|--|--|--v--|--v-----v--|--v--|--v--^--o
-//     |  |     |              |  |  |  |  |  |  |  |  |  |  |     |           |     |     |
-//  o--v--|--^--|--^-----------v--|--|--|--|--|--|--|--v--|--|-----|--^--------|-----v--^--v--o
-//        |  |  |  |              |  |  |  |  |  |  |     |  |     |  |        |        |
-//  o--^--v--|--|--|--^-----------v--|--|--|--|--|--v-----|--|-----|--v--------|--^-----v-----o
-//     |     |  |  |  |              |  |  |  |  |        |  |     |           |  |
-//  o--v-----v--|--|--|--^-----------v--|--|--|--|--------|--v-----|--^--^-----|--|--^--------o
-//              |  |  |  |              |  |  |  |        |        |  |  |     |  |  |
-//  o--^--^-----v--|--|--|--------------v--|--|--|--------v--------|--|--|-----v--v--v--------o
-//     |  |        |  |  |                 |  |  |                 |  |  |
-//  o--v--|--^-----v--|--|-----------------v--|--|--^--------------v--|--v--------------------o
-//        |  |        |  |                    |  |  |                 |
-//  o--^--v--|--------v--|--------------------v--|--v-----------------v-----------------------o
-//     |     |           |                       |
-//  o--v-----v-----------v-----------------------v--------------------------------------------o
-//
-//  [[0,1],[2,3],[4,5],[6,7],[8,9],[10,11],[12,13],[14,15]]
-//  [[0,2],[4,6],[8,10],[12,14],[1,3],[5,7],[9,11],[13,15]]
-//  [[0,4],[8,12],[1,5],[9,13],[2,6],[10,14],[3,7],[11,15]]
-//  [[0,8],[1,9],[2,10],[3,11],[4,12],[5,13],[6,14],[7,15]]
-//  [[5,10],[6,9],[3,12],[13,14],[7,11],[1,2],[4,8]]
-//  [[1,4],[7,13],[2,8],[11,14],[5,6],[9,10]]
-//  [[2,4],[11,13],[3,8],[7,12]]
-//  [[6,8],[10,12],[3,5],[7,9]]
-//  [[3,4],[5,6],[7,8],[9,10],[11,12]]
-//  [[6,7],[8,9]]
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#define SORT_NETWORK_16(TYPE, CMP, begin)                                      \
-  do {                                                                         \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[11]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[12], begin[13]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[14], begin[15]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[12], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[3]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[13], begin[15]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[15]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[14]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[15]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[13], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[11]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[2]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[4], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[1], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[13]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[14]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[2], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[13]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[12]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[10], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[5]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[9]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[3], begin[4]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[5], begin[6]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[7], begin[8]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[9], begin[10]);                             \
-    SORT_CMP_SWAP(TYPE, CMP, begin[11], begin[12]);                            \
-    SORT_CMP_SWAP(TYPE, CMP, begin[6], begin[7]);                              \
-    SORT_CMP_SWAP(TYPE, CMP, begin[8], begin[9]);                              \
-  } while (0)
-
-#define SORT_INNER(TYPE, CMP, begin, end, len)                                 \
-  switch (len) {                                                               \
-  default:                                                                     \
-    __unreachable();                                                           \
-  case 0:                                                                      \
-  case 1:                                                                      \
-    break;                                                                     \
-  case 2:                                                                      \
-    SORT_CMP_SWAP(TYPE, CMP, begin[0], begin[1]);                              \
-    break;                                                                     \
-  case 3:                                                                      \
-    SORT_NETWORK_3(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 4:                                                                      \
-    SORT_NETWORK_4(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 5:                                                                      \
-    SORT_NETWORK_5(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 6:                                                                      \
-    SORT_NETWORK_6(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 7:                                                                      \
-    SORT_NETWORK_7(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 8:                                                                      \
-    SORT_NETWORK_8(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 9:                                                                      \
-    SORT_NETWORK_9(TYPE, CMP, begin);                                          \
-    break;                                                                     \
-  case 10:                                                                     \
-    SORT_NETWORK_10(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  case 11:                                                                     \
-    SORT_NETWORK_11(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  case 12:                                                                     \
-    SORT_NETWORK_12(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  case 13:                                                                     \
-    SORT_NETWORK_13(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  case 14:                                                                     \
-    SORT_NETWORK_14(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  case 15:                                                                     \
-    SORT_NETWORK_15(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  case 16:                                                                     \
-    SORT_NETWORK_16(TYPE, CMP, begin);                                         \
-    break;                                                                     \
-  }
-
-#define SORT_SWAP(TYPE, a, b)                                                  \
-  do {                                                                         \
-    const TYPE swap_tmp = (a);                                                 \
-    (a) = (b);                                                                 \
-    (b) = swap_tmp;                                                            \
-  } while (0)
-
-#define SORT_PUSH(low, high)                                                   \
-  do {                                                                         \
-    top->lo = (low);                                                           \
-    top->hi = (high);                                                          \
-    ++top;                                                                     \
-  } while (0)
-
-#define SORT_POP(low, high)                                                    \
-  do {                                                                         \
-    --top;                                                                     \
-    low = top->lo;                                                             \
-    high = top->hi;                                                            \
-  } while (0)
-
-#define SORT_IMPL(NAME, EXPECT_LOW_CARDINALITY_OR_PRESORTED, TYPE, CMP)        \
-                                                                               \
-  static __inline bool NAME##_is_sorted(const TYPE *first, const TYPE *last) { \
-    while (++first <= last)                                                    \
-      if (CMP(first[0], first[-1]))                                            \
-        return false;                                                          \
-    return true;                                                               \
-  }                                                                            \
-                                                                               \
-  typedef struct {                                                             \
-    TYPE *lo, *hi;                                                             \
-  } NAME##_stack;                                                              \
-                                                                               \
-  static __hot void NAME(TYPE *const begin, TYPE *const end) {                 \
-    NAME##_stack stack[sizeof(unsigned) * CHAR_BIT], *top = stack;             \
-                                                                               \
-    TYPE *hi = end - 1;                                                        \
-    TYPE *lo = begin;                                                          \
-    while (true) {                                                             \
-      const ptrdiff_t len = hi - lo;                                           \
-      if (len < 16) {                                                          \
-        SORT_INNER(TYPE, CMP, lo, hi + 1, len + 1);                            \
-        if (unlikely(top == stack))                                            \
-          break;                                                               \
-        SORT_POP(lo, hi);                                                      \
-        continue;                                                              \
-      }                                                                        \
-                                                                               \
-      TYPE *mid = lo + (len >> 1);                                             \
-      SORT_CMP_SWAP(TYPE, CMP, *lo, *mid);                                     \
-      SORT_CMP_SWAP(TYPE, CMP, *mid, *hi);                                     \
-      SORT_CMP_SWAP(TYPE, CMP, *lo, *mid);                                     \
-                                                                               \
-      TYPE *right = hi - 1;                                                    \
-      TYPE *left = lo + 1;                                                     \
-      while (1) {                                                              \
-        while (CMP(*left, *mid))                                               \
-          ++left;                                                              \
-        while (CMP(*mid, *right))                                              \
-          --right;                                                             \
-        if (unlikely(left > right)) {                                          \
-          if (EXPECT_LOW_CARDINALITY_OR_PRESORTED) {                           \
-            if (NAME##_is_sorted(lo, right))                                   \
-              lo = right + 1;                                                  \
-            if (NAME##_is_sorted(left, hi))                                    \
-              hi = left;                                                       \
-          }                                                                    \
-          break;                                                               \
-        }                                                                      \
-        SORT_SWAP(TYPE, *left, *right);                                        \
-        mid = (mid == left) ? right : (mid == right) ? left : mid;             \
-        ++left;                                                                \
-        --right;                                                               \
-      }                                                                        \
-                                                                               \
-      if (right - lo > hi - left) {                                            \
-        SORT_PUSH(lo, right);                                                  \
-        lo = left;                                                             \
-      } else {                                                                 \
-        SORT_PUSH(left, hi);                                                   \
-        hi = right;                                                            \
-      }                                                                        \
-    }                                                                          \
-                                                                               \
-    if (mdbx_audit_enabled()) {                                                \
-      for (TYPE *scan = begin + 1; scan < end; ++scan)                         \
-        assert(CMP(scan[-1], scan[0]));                                        \
-    }                                                                          \
-  }
-
-/*------------------------------------------------------------------------------
- * LY: Binary search */
-
-#define SEARCH_IMPL(NAME, TYPE_LIST, TYPE_ARG, CMP)                            \
-  static __always_inline const TYPE_LIST *NAME(                                \
-      const TYPE_LIST *first, unsigned length, const TYPE_ARG item) {          \
-    const TYPE_LIST *const begin = first, *const end = begin + length;         \
-                                                                               \
-    while (length > 3) {                                                       \
-      const unsigned whole = length;                                           \
-      length >>= 1;                                                            \
-      const TYPE_LIST *const middle = first + length;                          \
-      if (CMP(*middle, item)) {                                                \
-        first = middle + 1;                                                    \
-        length = whole - length - 1;                                           \
-      }                                                                        \
-    }                                                                          \
-                                                                               \
-    switch (length) {                                                          \
-    case 3:                                                                    \
-      if (!CMP(*first, item))                                                  \
-        break;                                                                 \
-      ++first;                                                                 \
-      __fallthrough /* fall through */;                                        \
-    case 2:                                                                    \
-      if (!CMP(*first, item))                                                  \
-        break;                                                                 \
-      ++first;                                                                 \
-      __fallthrough /* fall through */;                                        \
-    case 1:                                                                    \
-      if (!CMP(*first, item))                                                  \
-        break;                                                                 \
-      ++first;                                                                 \
-      __fallthrough /* fall through */;                                        \
-    case 0:                                                                    \
-      break;                                                                   \
-    default:                                                                   \
-      __unreachable();                                                         \
-    }                                                                          \
-                                                                               \
-    if (mdbx_audit_enabled()) {                                                \
-      for (const TYPE_LIST *scan = begin; scan < first; ++scan)                \
-        assert(CMP(*scan, item));                                              \
-      for (const TYPE_LIST *scan = first; scan < end; ++scan)                  \
-        assert(!CMP(*scan, item));                                             \
-      (void)begin, (void)end;                                                  \
-    }                                                                          \
-                                                                               \
-    return first;                                                              \
-  }
-
-/*----------------------------------------------------------------------------*/
-
-static __always_inline size_t pnl2bytes(const size_t size) {
-  assert(size > 0 && size <= MDBX_PGL_LIMIT);
-  size_t bytes =
-      ceil_powerof2(MDBX_ASSUME_MALLOC_OVERHEAD + sizeof(pgno_t) * (size + 2),
-                    MDBX_PNL_GRANULATE * sizeof(pgno_t)) -
-      MDBX_ASSUME_MALLOC_OVERHEAD;
-  return bytes;
-}
-
-static __always_inline pgno_t bytes2pnl(const size_t bytes) {
-  size_t size = bytes / sizeof(pgno_t);
-  assert(size > 2 && size <= MDBX_PGL_LIMIT);
-  return (pgno_t)size - 2;
-}
-
-static MDBX_PNL mdbx_pnl_alloc(size_t size) {
-  size_t bytes = pnl2bytes(size);
-  MDBX_PNL pl = mdbx_malloc(bytes);
-  if (likely(pl)) {
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-    bytes = malloc_usable_size(pl);
-#endif /* malloc_usable_size */
-    pl[0] = bytes2pnl(bytes);
-    assert(pl[0] >= size);
-    pl[1] = 0;
-    pl += 1;
-  }
-  return pl;
-}
-
-static void mdbx_pnl_free(MDBX_PNL pl) {
-  if (likely(pl))
-    mdbx_free(pl - 1);
-}
-
-/* Shrink the PNL to the default size if it has grown larger */
-static void mdbx_pnl_shrink(MDBX_PNL *ppl) {
-  assert(bytes2pnl(pnl2bytes(MDBX_PNL_INITIAL)) == MDBX_PNL_INITIAL);
-  assert(MDBX_PNL_SIZE(*ppl) <= MDBX_PGL_LIMIT &&
-         MDBX_PNL_ALLOCLEN(*ppl) >= MDBX_PNL_SIZE(*ppl));
-  MDBX_PNL_SIZE(*ppl) = 0;
-  if (unlikely(MDBX_PNL_ALLOCLEN(*ppl) >
-               MDBX_PNL_INITIAL * 2 - MDBX_CACHELINE_SIZE / sizeof(pgno_t))) {
-    size_t bytes = pnl2bytes(MDBX_PNL_INITIAL);
-    MDBX_PNL pl = mdbx_realloc(*ppl - 1, bytes);
-    if (likely(pl)) {
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-      bytes = malloc_usable_size(pl);
-#endif /* malloc_usable_size */
-      *pl = bytes2pnl(bytes);
-      *ppl = pl + 1;
-    }
-  }
-}
-
-/* Grow the PNL to the size growed to at least given size */
-static int mdbx_pnl_reserve(MDBX_PNL *ppl, const size_t wanna) {
-  const size_t allocated = MDBX_PNL_ALLOCLEN(*ppl);
-  assert(MDBX_PNL_SIZE(*ppl) <= MDBX_PGL_LIMIT &&
-         MDBX_PNL_ALLOCLEN(*ppl) >= MDBX_PNL_SIZE(*ppl));
-  if (likely(allocated >= wanna))
-    return MDBX_SUCCESS;
-
-  if (unlikely(wanna > /* paranoia */ MDBX_PGL_LIMIT)) {
-    mdbx_error("PNL too long (%zu > %zu)", wanna, (size_t)MDBX_PGL_LIMIT);
-    return MDBX_TXN_FULL;
-  }
-
-  const size_t size = (wanna + wanna - allocated < MDBX_PGL_LIMIT)
-                          ? wanna + wanna - allocated
-                          : MDBX_PGL_LIMIT;
-  size_t bytes = pnl2bytes(size);
-  MDBX_PNL pl = mdbx_realloc(*ppl - 1, bytes);
-  if (likely(pl)) {
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-    bytes = malloc_usable_size(pl);
-#endif /* malloc_usable_size */
-    *pl = bytes2pnl(bytes);
-    assert(*pl >= wanna);
-    *ppl = pl + 1;
-    return MDBX_SUCCESS;
-  }
-  return MDBX_ENOMEM;
-}
-
-/* Make room for num additional elements in an PNL */
-static __always_inline int __must_check_result mdbx_pnl_need(MDBX_PNL *ppl,
-                                                             size_t num) {
-  assert(MDBX_PNL_SIZE(*ppl) <= MDBX_PGL_LIMIT &&
-         MDBX_PNL_ALLOCLEN(*ppl) >= MDBX_PNL_SIZE(*ppl));
-  assert(num <= MDBX_PGL_LIMIT);
-  const size_t wanna = MDBX_PNL_SIZE(*ppl) + num;
-  return likely(MDBX_PNL_ALLOCLEN(*ppl) >= wanna)
-             ? MDBX_SUCCESS
-             : mdbx_pnl_reserve(ppl, wanna);
-}
-
-static __always_inline void mdbx_pnl_xappend(MDBX_PNL pl, pgno_t pgno) {
-  assert(MDBX_PNL_SIZE(pl) < MDBX_PNL_ALLOCLEN(pl));
-  if (mdbx_audit_enabled()) {
-    for (unsigned i = MDBX_PNL_SIZE(pl); i > 0; --i)
-      assert(pgno != pl[i]);
-  }
-  MDBX_PNL_SIZE(pl) += 1;
-  MDBX_PNL_LAST(pl) = pgno;
-}
-
-/* Append an pgno range onto an unsorted PNL */
-__always_inline static int __must_check_result
-mdbx_pnl_append_range(bool spilled, MDBX_PNL *ppl, pgno_t pgno, unsigned n) {
-  assert(n > 0);
-  int rc = mdbx_pnl_need(ppl, n);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  const MDBX_PNL pnl = *ppl;
-#if MDBX_PNL_ASCENDING
-  unsigned w = MDBX_PNL_SIZE(pnl);
-  do {
-    pnl[++w] = pgno;
-    pgno += spilled ? 2 : 1;
-  } while (--n);
-  MDBX_PNL_SIZE(pnl) = w;
-#else
-  unsigned w = MDBX_PNL_SIZE(pnl) + n;
-  MDBX_PNL_SIZE(pnl) = w;
-  do {
-    pnl[w--] = pgno;
-    pgno += spilled ? 2 : 1;
-  } while (--n);
-#endif
-
-  return MDBX_SUCCESS;
-}
-
-/* Append an pgno range into the sorted PNL */
-static __hot int __must_check_result mdbx_pnl_insert_range(MDBX_PNL *ppl,
-                                                           pgno_t pgno,
-                                                           unsigned n) {
-  assert(n > 0);
-  int rc = mdbx_pnl_need(ppl, n);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  const MDBX_PNL pnl = *ppl;
-  unsigned r = MDBX_PNL_SIZE(pnl), w = r + n;
-  MDBX_PNL_SIZE(pnl) = w;
-  while (r && MDBX_PNL_DISORDERED(pnl[r], pgno))
-    pnl[w--] = pnl[r--];
-
-  for (pgno_t fill = MDBX_PNL_ASCENDING ? pgno + n : pgno; w > r; --w)
-    pnl[w] = MDBX_PNL_ASCENDING ? --fill : fill++;
-
-  return MDBX_SUCCESS;
-}
-
-static bool mdbx_pnl_check(const MDBX_PNL pl, const pgno_t limit) {
-  if (likely(MDBX_PNL_SIZE(pl))) {
-    assert(MDBX_PNL_LEAST(pl) >= MIN_PAGENO);
-    assert(MDBX_PNL_MOST(pl) < limit);
-    assert(MDBX_PNL_SIZE(pl) <= MDBX_PGL_LIMIT);
-    if (unlikely(MDBX_PNL_SIZE(pl) > MDBX_PGL_LIMIT))
-      return false;
-    if (unlikely(MDBX_PNL_LEAST(pl) < MIN_PAGENO))
-      return false;
-    if (unlikely(MDBX_PNL_MOST(pl) >= limit))
-      return false;
-    if (mdbx_audit_enabled()) {
-      for (const pgno_t *scan = &MDBX_PNL_LAST(pl); --scan > pl;) {
-        assert(MDBX_PNL_ORDERED(scan[0], scan[1]));
-        if (unlikely(!MDBX_PNL_ORDERED(scan[0], scan[1])))
-          return false;
-      }
-    }
-  }
-  return true;
-}
-
-static __always_inline bool mdbx_pnl_check4assert(const MDBX_PNL pl,
-                                                  const pgno_t limit) {
-  if (unlikely(pl == nullptr))
-    return true;
-  assert(MDBX_PNL_ALLOCLEN(pl) >= MDBX_PNL_SIZE(pl));
-  if (unlikely(MDBX_PNL_ALLOCLEN(pl) < MDBX_PNL_SIZE(pl)))
-    return false;
-  return mdbx_pnl_check(pl, limit);
-}
-
-/* Merge an PNL onto an PNL. The destination PNL must be big enough */
-static void __hot mdbx_pnl_xmerge(MDBX_PNL dst, const MDBX_PNL src) {
-  assert(mdbx_pnl_check4assert(dst, MAX_PAGENO + 1));
-  assert(mdbx_pnl_check(src, MAX_PAGENO + 1));
-  const size_t total = MDBX_PNL_SIZE(dst) + MDBX_PNL_SIZE(src);
-  assert(MDBX_PNL_ALLOCLEN(dst) >= total);
-  pgno_t *w = dst + total;
-  pgno_t *d = dst + MDBX_PNL_SIZE(dst);
-  const pgno_t *s = src + MDBX_PNL_SIZE(src);
-  dst[0] = /* detent for scan below */ (MDBX_PNL_ASCENDING ? 0 : ~(pgno_t)0);
-  while (s > src) {
-    while (MDBX_PNL_ORDERED(*s, *d))
-      *w-- = *d--;
-    *w-- = *s--;
-  }
-  MDBX_PNL_SIZE(dst) = (pgno_t)total;
-  assert(mdbx_pnl_check4assert(dst, MAX_PAGENO + 1));
-}
-
-static void mdbx_spill_remove(MDBX_txn *txn, unsigned idx, unsigned npages) {
-  mdbx_tassert(txn, idx > 0 && idx <= MDBX_PNL_SIZE(txn->tw.spill_pages) &&
-                        txn->tw.spill_least_removed > 0);
-  txn->tw.spill_least_removed =
-      (idx < txn->tw.spill_least_removed) ? idx : txn->tw.spill_least_removed;
-  txn->tw.spill_pages[idx] |= 1;
-  MDBX_PNL_SIZE(txn->tw.spill_pages) -=
-      (idx == MDBX_PNL_SIZE(txn->tw.spill_pages));
-
-  while (unlikely(npages > 1)) {
-    const pgno_t pgno = (txn->tw.spill_pages[idx] >> 1) + 1;
-    if (MDBX_PNL_ASCENDING) {
-      if (++idx > MDBX_PNL_SIZE(txn->tw.spill_pages) ||
-          (txn->tw.spill_pages[idx] >> 1) != pgno)
-        return;
-    } else {
-      if (--idx < 1 || (txn->tw.spill_pages[idx] >> 1) != pgno)
-        return;
-      txn->tw.spill_least_removed = (idx < txn->tw.spill_least_removed)
-                                        ? idx
-                                        : txn->tw.spill_least_removed;
-    }
-    txn->tw.spill_pages[idx] |= 1;
-    MDBX_PNL_SIZE(txn->tw.spill_pages) -=
-        (idx == MDBX_PNL_SIZE(txn->tw.spill_pages));
-    --npages;
-  }
-}
-
-static MDBX_PNL mdbx_spill_purge(MDBX_txn *txn) {
-  mdbx_tassert(txn, txn->tw.spill_least_removed > 0);
-  const MDBX_PNL sl = txn->tw.spill_pages;
-  if (txn->tw.spill_least_removed != INT_MAX) {
-    unsigned len = MDBX_PNL_SIZE(sl), r, w;
-    for (w = r = txn->tw.spill_least_removed; r <= len; ++r) {
-      sl[w] = sl[r];
-      w += 1 - (sl[r] & 1);
-    }
-    for (size_t i = 1; i < w; ++i)
-      mdbx_tassert(txn, (sl[i] & 1) == 0);
-    MDBX_PNL_SIZE(sl) = w - 1;
-    txn->tw.spill_least_removed = INT_MAX;
-  } else {
-    for (size_t i = 1; i <= MDBX_PNL_SIZE(sl); ++i)
-      mdbx_tassert(txn, (sl[i] & 1) == 0);
-  }
-  return sl;
-}
-
-SORT_IMPL(pgno_sort, false, pgno_t, MDBX_PNL_ORDERED)
-static __hot void mdbx_pnl_sort(MDBX_PNL pnl) {
-  pgno_sort(MDBX_PNL_BEGIN(pnl), MDBX_PNL_END(pnl));
-  assert(mdbx_pnl_check(pnl, MAX_PAGENO + 1));
-}
-
-/* Search for an pgno in an PNL.
- * Returns The index of the first item greater than or equal to pgno. */
-SEARCH_IMPL(pgno_bsearch, pgno_t, pgno_t, MDBX_PNL_ORDERED)
-
-static __hot unsigned mdbx_pnl_search(const MDBX_PNL pnl, pgno_t pgno) {
-  assert(mdbx_pnl_check4assert(pnl, MAX_PAGENO + 1));
-  const pgno_t *begin = MDBX_PNL_BEGIN(pnl);
-  const pgno_t *it = pgno_bsearch(begin, MDBX_PNL_SIZE(pnl), pgno);
-  const pgno_t *end = begin + MDBX_PNL_SIZE(pnl);
-  assert(it >= begin && it <= end);
-  if (it != begin)
-    assert(MDBX_PNL_ORDERED(it[-1], pgno));
-  if (it != end)
-    assert(!MDBX_PNL_ORDERED(it[0], pgno));
-  return (unsigned)(it - begin + 1);
-}
-
-static __inline unsigned mdbx_pnl_exist(const MDBX_PNL pnl, pgno_t pgno) {
-  unsigned n = mdbx_pnl_search(pnl, pgno);
-  return (n <= MDBX_PNL_SIZE(pnl) && pnl[n] == pgno) ? n : 0;
-}
-
-static __inline unsigned mdbx_pnl_intersect(const MDBX_PNL pnl, pgno_t pgno,
-                                            unsigned npages) {
-  const unsigned len = MDBX_PNL_SIZE(pnl);
-  if (mdbx_log_enabled(MDBX_LOG_EXTRA)) {
-    mdbx_debug_extra("PNL len %u [", len);
-    for (unsigned i = 1; i <= len; ++i)
-      mdbx_debug_extra_print(" %" PRIaPGNO, pnl[i]);
-    mdbx_debug_extra_print("%s\n", "]");
-  }
-  const pgno_t range_last = pgno + npages - 1;
-#if MDBX_PNL_ASCENDING
-  const unsigned n = mdbx_pnl_search(pnl, pgno);
-  assert(n && (n == MDBX_PNL_SIZE(pnl) + 1 || pgno <= pnl[n]));
-  const bool rc = n <= MDBX_PNL_SIZE(pnl) && pnl[n] <= range_last;
-#else
-  const unsigned n = mdbx_pnl_search(pnl, range_last);
-  assert(n && (n == MDBX_PNL_SIZE(pnl) + 1 || range_last >= pnl[n]));
-  const bool rc = n <= MDBX_PNL_SIZE(pnl) && pnl[n] >= pgno;
-#endif
-  if (mdbx_assert_enabled()) {
-    bool check = false;
-    for (unsigned i = 0; i < npages; ++i)
-      check |= mdbx_pnl_exist(pnl, pgno + i) != 0;
-    assert(check == rc);
-  }
-  return rc;
-}
-
-/*----------------------------------------------------------------------------*/
-
-static __always_inline size_t txl2bytes(const size_t size) {
-  assert(size > 0 && size <= MDBX_TXL_MAX * 2);
-  size_t bytes =
-      ceil_powerof2(MDBX_ASSUME_MALLOC_OVERHEAD + sizeof(txnid_t) * (size + 2),
-                    MDBX_TXL_GRANULATE * sizeof(txnid_t)) -
-      MDBX_ASSUME_MALLOC_OVERHEAD;
-  return bytes;
-}
-
-static __always_inline size_t bytes2txl(const size_t bytes) {
-  size_t size = bytes / sizeof(txnid_t);
-  assert(size > 2 && size <= MDBX_TXL_MAX * 2);
-  return size - 2;
-}
-
-static MDBX_TXL mdbx_txl_alloc(void) {
-  size_t bytes = txl2bytes(MDBX_TXL_INITIAL);
-  MDBX_TXL tl = mdbx_malloc(bytes);
-  if (likely(tl)) {
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-    bytes = malloc_usable_size(tl);
-#endif /* malloc_usable_size */
-    tl[0] = bytes2txl(bytes);
-    assert(tl[0] >= MDBX_TXL_INITIAL);
-    tl[1] = 0;
-    tl += 1;
-  }
-  return tl;
-}
-
-static void mdbx_txl_free(MDBX_TXL tl) {
-  if (likely(tl))
-    mdbx_free(tl - 1);
-}
-
-static int mdbx_txl_reserve(MDBX_TXL *ptl, const size_t wanna) {
-  const size_t allocated = (size_t)MDBX_PNL_ALLOCLEN(*ptl);
-  assert(MDBX_PNL_SIZE(*ptl) <= MDBX_TXL_MAX &&
-         MDBX_PNL_ALLOCLEN(*ptl) >= MDBX_PNL_SIZE(*ptl));
-  if (likely(allocated >= wanna))
-    return MDBX_SUCCESS;
-
-  if (unlikely(wanna > /* paranoia */ MDBX_TXL_MAX)) {
-    mdbx_error("TXL too long (%zu > %zu)", wanna, (size_t)MDBX_TXL_MAX);
-    return MDBX_TXN_FULL;
-  }
-
-  const size_t size = (wanna + wanna - allocated < MDBX_TXL_MAX)
-                          ? wanna + wanna - allocated
-                          : MDBX_TXL_MAX;
-  size_t bytes = txl2bytes(size);
-  MDBX_TXL tl = mdbx_realloc(*ptl - 1, bytes);
-  if (likely(tl)) {
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-    bytes = malloc_usable_size(tl);
-#endif /* malloc_usable_size */
-    *tl = bytes2txl(bytes);
-    assert(*tl >= wanna);
-    *ptl = tl + 1;
-    return MDBX_SUCCESS;
-  }
-  return MDBX_ENOMEM;
-}
-
-static __always_inline int __must_check_result mdbx_txl_need(MDBX_TXL *ptl,
-                                                             size_t num) {
-  assert(MDBX_PNL_SIZE(*ptl) <= MDBX_TXL_MAX &&
-         MDBX_PNL_ALLOCLEN(*ptl) >= MDBX_PNL_SIZE(*ptl));
-  assert(num <= MDBX_PGL_LIMIT);
-  const size_t wanna = (size_t)MDBX_PNL_SIZE(*ptl) + num;
-  return likely(MDBX_PNL_ALLOCLEN(*ptl) >= wanna)
-             ? MDBX_SUCCESS
-             : mdbx_txl_reserve(ptl, wanna);
-}
-
-static __always_inline void mdbx_txl_xappend(MDBX_TXL tl, txnid_t id) {
-  assert(MDBX_PNL_SIZE(tl) < MDBX_PNL_ALLOCLEN(tl));
-  MDBX_PNL_SIZE(tl) += 1;
-  MDBX_PNL_LAST(tl) = id;
-}
-
-#define TXNID_SORT_CMP(first, last) ((first) > (last))
-SORT_IMPL(txnid_sort, false, txnid_t, TXNID_SORT_CMP)
-static void mdbx_txl_sort(MDBX_TXL tl) {
-  txnid_sort(MDBX_PNL_BEGIN(tl), MDBX_PNL_END(tl));
-}
-
-static int __must_check_result mdbx_txl_append(MDBX_TXL *ptl, txnid_t id) {
-  if (unlikely(MDBX_PNL_SIZE(*ptl) == MDBX_PNL_ALLOCLEN(*ptl))) {
-    int rc = mdbx_txl_need(ptl, MDBX_TXL_GRANULATE);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-  mdbx_txl_xappend(*ptl, id);
-  return MDBX_SUCCESS;
-}
-
-/*----------------------------------------------------------------------------*/
-
-static __always_inline size_t dpl2bytes(const ptrdiff_t size) {
-  assert(size > 2 && (size_t)size <= MDBX_PGL_LIMIT);
-  size_t bytes = ceil_powerof2(MDBX_ASSUME_MALLOC_OVERHEAD + sizeof(MDBX_dpl) +
-                                   (size + 2) * sizeof(MDBX_dp),
-                               MDBX_PNL_GRANULATE * sizeof(void *) * 2) -
-                 MDBX_ASSUME_MALLOC_OVERHEAD;
-  return bytes;
-}
-
-static __always_inline unsigned bytes2dpl(const ptrdiff_t bytes) {
-  size_t size = (bytes - sizeof(MDBX_dpl)) / sizeof(MDBX_dp);
-  assert(size > 4 && size <= MDBX_PGL_LIMIT + MDBX_PNL_GRANULATE);
-  return (unsigned)size - 2;
-}
-
-static __always_inline void mdbx_dpl_clear(MDBX_dpl *dl) {
-  dl->sorted = dl->length = 0;
-}
-
-static void mdbx_dpl_free(MDBX_txn *txn) {
-  if (likely(txn->tw.dirtylist)) {
-    mdbx_free(txn->tw.dirtylist);
-    txn->tw.dirtylist = NULL;
-  }
-}
-
-static MDBX_dpl *mdbx_dpl_reserve(MDBX_txn *txn, size_t size) {
-  mdbx_tassert(txn,
-               txn->tw.dirtylist == NULL || txn->tw.dirtylist->length <= size);
-  size_t bytes = dpl2bytes((size < MDBX_PGL_LIMIT) ? size : MDBX_PGL_LIMIT);
-  MDBX_dpl *const dl = mdbx_realloc(txn->tw.dirtylist, bytes);
-  if (likely(dl)) {
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-    bytes = malloc_usable_size(dl);
-#endif /* malloc_usable_size */
-    dl->allocated = bytes2dpl(bytes);
-    dl->items[0].pgno = 0;
-    dl->items[0].ptr = nullptr;
-    mdbx_tassert(txn, txn->tw.dirtylist == NULL || dl->length <= dl->allocated);
-    txn->tw.dirtylist = dl;
-  }
-  return dl;
-}
-
-static int mdbx_dpl_alloc(MDBX_txn *txn) {
-  mdbx_tassert(txn,
-               (txn->mt_flags & MDBX_TXN_RDONLY) == 0 && !txn->tw.dirtylist);
-  MDBX_dpl *const dl =
-      mdbx_dpl_reserve(txn, txn->mt_env->me_options.dp_initial);
-  if (unlikely(!dl))
-    return MDBX_ENOMEM;
-  mdbx_dpl_clear(dl);
-  return MDBX_SUCCESS;
-}
-
-#define DP_SORT_CMP(first, last) ((first).pgno < (last).pgno)
-SORT_IMPL(dp_sort, false, MDBX_dp, DP_SORT_CMP)
-static __always_inline MDBX_dpl *mdbx_dpl_sort(MDBX_dpl *dl) {
-  assert(dl->length <= MDBX_PGL_LIMIT);
-  assert(dl->sorted <= dl->length);
-  if (dl->sorted != dl->length) {
-    dl->sorted = dl->length;
-    dp_sort(dl->items + 1, dl->items + dl->length + 1);
-  }
-  return dl;
-}
-
-/* Returns the index of the first dirty-page whose pgno
- * member is greater than or equal to id. */
-#define DP_SEARCH_CMP(dp, id) ((dp).pgno < (id))
-SEARCH_IMPL(dp_bsearch, MDBX_dp, pgno_t, DP_SEARCH_CMP)
-
-static unsigned __hot mdbx_dpl_search(MDBX_dpl *dl, pgno_t pgno) {
-  if (mdbx_audit_enabled()) {
-    for (const MDBX_dp *ptr = dl->items + dl->sorted; --ptr > dl->items;) {
-      assert(ptr[0].pgno < ptr[1].pgno);
-      assert(ptr[0].pgno >= NUM_METAS);
-    }
-  }
-
-  switch (dl->length - dl->sorted) {
-  default:
-    /* sort a whole */
-    dl->sorted = dl->length;
-    dp_sort(dl->items + 1, dl->items + dl->length + 1);
-    break;
-  case 0:
-    /* whole sorted cases */
-    break;
-
-#define LINEAR_SEARCH_CASE(N)                                                  \
-  case N:                                                                      \
-    if (dl->items[dl->length - N + 1].pgno == pgno)                            \
-      return dl->length - N + 1;                                               \
-    __fallthrough
-
-    /* try linear search until the threshold */
-    LINEAR_SEARCH_CASE(16); /* fall through */
-    LINEAR_SEARCH_CASE(15); /* fall through */
-    LINEAR_SEARCH_CASE(14); /* fall through */
-    LINEAR_SEARCH_CASE(13); /* fall through */
-    LINEAR_SEARCH_CASE(12); /* fall through */
-    LINEAR_SEARCH_CASE(11); /* fall through */
-    LINEAR_SEARCH_CASE(10); /* fall through */
-    LINEAR_SEARCH_CASE(9);  /* fall through */
-    LINEAR_SEARCH_CASE(8);  /* fall through */
-    LINEAR_SEARCH_CASE(7);  /* fall through */
-    LINEAR_SEARCH_CASE(6);  /* fall through */
-    LINEAR_SEARCH_CASE(5);  /* fall through */
-    LINEAR_SEARCH_CASE(4);  /* fall through */
-    LINEAR_SEARCH_CASE(3);  /* fall through */
-    LINEAR_SEARCH_CASE(2);  /* fall through */
-  case 1:
-    if (dl->items[dl->length].pgno == pgno)
-      return dl->length;
-    /* continue bsearch on the sorted part */
-    break;
-  }
-  return (unsigned)(dp_bsearch(dl->items + 1, dl->sorted, pgno) - dl->items);
-}
-
-static __inline bool mdbx_dpl_intersect(MDBX_dpl *dl, pgno_t pgno,
-                                        unsigned npages) {
-  assert(dl->sorted == dl->length);
-  unsigned const n = mdbx_dpl_search(dl, pgno);
-  assert(n >= 1 && n <= dl->length + 1);
-  assert(n > dl->length || pgno <= dl->items[n].pgno);
-  assert(n == 1 || pgno > dl->items[n - 1].pgno);
-  const MDBX_page *const prev = dl->items[n - 1].ptr;
-  const bool rc =
-      (/* intersection with founded */ n <= dl->length &&
-       pgno + npages > dl->items[n].pgno) ||
-      (/* intersection with prev */ n > 1 && unlikely(IS_OVERFLOW(prev)) &&
-       prev->mp_pgno + prev->mp_pages > pgno);
-  if (mdbx_assert_enabled()) {
-    bool check = false;
-    for (unsigned i = 1; i <= dl->length; ++i) {
-      const MDBX_page *const dp = dl->items[i].ptr;
-      if (!(dp->mp_pgno /* begin */ >= /* end */ pgno + npages ||
-            dp->mp_pgno + (IS_OVERFLOW(dp) ? dp->mp_pages : 1) /* end */ <=
-                /* begin */ pgno))
-        check |= true;
-    }
-    assert(check == rc);
-  }
-  return rc;
-}
-
-static __always_inline unsigned mdbx_dpl_exist(MDBX_dpl *dl, pgno_t pgno) {
-  unsigned i = mdbx_dpl_search(dl, pgno);
-  assert((int)i > 0);
-  return (i <= dl->length && dl->items[i].pgno == pgno) ? i : 0;
-}
-
-static __always_inline MDBX_page *mdbx_dpl_find(MDBX_dpl *dl, pgno_t pgno) {
-  const unsigned i = mdbx_dpl_search(dl, pgno);
-  assert((int)i > 0);
-  return (i <= dl->length && dl->items[i].pgno == pgno) ? dl->items[i].ptr
-                                                        : nullptr;
-}
-
-static __maybe_unused const MDBX_page *debug_dpl_find(const MDBX_dpl *dl,
-                                                      const pgno_t pgno) {
-  for (unsigned i = dl->length; i > dl->sorted; --i)
-    if (dl->items[i].pgno == pgno)
-      return dl->items[i].ptr;
-
-  if (dl->sorted) {
-    const unsigned i =
-        (unsigned)(dp_bsearch(dl->items + 1, dl->sorted, pgno) - dl->items);
-    if (i <= dl->sorted && dl->items[i].pgno == pgno)
-      return dl->items[i].ptr;
-  }
-  return nullptr;
-}
-
-static void mdbx_dpl_remove(MDBX_dpl *dl, unsigned i) {
-  assert((int)i > 0 && i <= dl->length);
-  dl->sorted -= dl->sorted >= i;
-  dl->length -= 1;
-  if (dl->length >= i)
-    memmove(dl->items + i, dl->items + i + 1,
-            (dl->length - i + 1) * sizeof(dl->items[0]));
-}
-
-static __always_inline int __must_check_result
-mdbx_dpl_append(MDBX_txn *txn, pgno_t pgno, MDBX_page *page) {
-  MDBX_dpl *dl = txn->tw.dirtylist;
-  assert(dl->length <= MDBX_PGL_LIMIT + MDBX_PNL_GRANULATE);
-  if (mdbx_audit_enabled()) {
-    for (unsigned i = dl->length; i > 0; --i) {
-      assert(dl->items[i].pgno != pgno);
-      if (unlikely(dl->items[i].pgno == pgno))
-        return MDBX_PROBLEM;
-    }
-  }
-
-  if (unlikely(dl->length == dl->allocated)) {
-    if (unlikely(dl->allocated >= MDBX_PGL_LIMIT)) {
-      mdbx_error("DPL is full (MDBX_PGL_LIMIT %u)", MDBX_PGL_LIMIT);
-      return MDBX_TXN_FULL;
-    }
-    const size_t size = (dl->allocated < MDBX_PNL_INITIAL * 42)
-                            ? dl->allocated + dl->allocated
-                            : dl->allocated + dl->allocated / 2;
-    dl = mdbx_dpl_reserve(txn, size);
-    if (unlikely(!dl))
-      return MDBX_ENOMEM;
-    mdbx_tassert(txn, dl->length < dl->allocated);
-  }
-
-  /* append page */
-  const unsigned n = dl->length + 1;
-  if (n == 1 || (dl->sorted >= dl->length && dl->items[n - 1].pgno < pgno))
-    dl->sorted = n;
-  dl->length = n;
-  dl->items[n].pgno = pgno;
-  dl->items[n].ptr = page;
-  return MDBX_SUCCESS;
-}
-
-/*----------------------------------------------------------------------------*/
-
-uint8_t mdbx_runtime_flags = MDBX_RUNTIME_FLAGS_INIT;
-uint8_t mdbx_loglevel = MDBX_LOG_FATAL;
-MDBX_debug_func *mdbx_debug_logger;
-
-static __must_check_result int mdbx_page_retire(MDBX_cursor *mc, MDBX_page *mp);
-static __must_check_result int mdbx_page_loose(MDBX_txn *txn, MDBX_page *mp);
-static int mdbx_page_alloc(MDBX_cursor *mc, const unsigned num,
-                           MDBX_page **const mp, int flags);
-static txnid_t mdbx_kick_longlived_readers(MDBX_env *env,
-                                           const txnid_t laggard);
-
-static int mdbx_page_new(MDBX_cursor *mc, uint32_t flags, unsigned num,
-                         MDBX_page **mp);
-static int mdbx_page_touch(MDBX_cursor *mc);
-static int mdbx_cursor_touch(MDBX_cursor *mc);
-
-#define MDBX_END_NAMES                                                         \
-  {                                                                            \
-    "committed", "empty-commit", "abort", "reset", "reset-tmp", "fail-begin",  \
-        "fail-beginchild"                                                      \
-  }
-enum {
-  /* mdbx_txn_end operation number, for logging */
-  MDBX_END_COMMITTED,
-  MDBX_END_PURE_COMMIT,
-  MDBX_END_ABORT,
-  MDBX_END_RESET,
-  MDBX_END_RESET_TMP,
-  MDBX_END_FAIL_BEGIN,
-  MDBX_END_FAIL_BEGINCHILD
-};
-#define MDBX_END_OPMASK 0x0F  /* mask for mdbx_txn_end() operation number */
-#define MDBX_END_UPDATE 0x10  /* update env state (DBIs) */
-#define MDBX_END_FREE 0x20    /* free txn unless it is MDBX_env.me_txn0 */
-#define MDBX_END_EOTDONE 0x40 /* txn's cursors already closed */
-#define MDBX_END_SLOT 0x80    /* release any reader slot if MDBX_NOTLS */
-static int mdbx_txn_end(MDBX_txn *txn, const unsigned mode);
-
-static int __must_check_result mdbx_page_get(MDBX_cursor *mc, pgno_t pgno,
-                                             MDBX_page **mp, int *lvl,
-                                             txnid_t pp_txnid);
-static int __must_check_result mdbx_page_search_root(MDBX_cursor *mc,
-                                                     const MDBX_val *key,
-                                                     int flags);
-
-#define MDBX_PS_MODIFY 1
-#define MDBX_PS_ROOTONLY 2
-#define MDBX_PS_FIRST 4
-#define MDBX_PS_LAST 8
-static int __must_check_result mdbx_page_search(MDBX_cursor *mc,
-                                                const MDBX_val *key, int flags);
-static int __must_check_result mdbx_page_merge(MDBX_cursor *csrc,
-                                               MDBX_cursor *cdst);
-static int __must_check_result mdbx_page_flush(MDBX_txn *txn,
-                                               const unsigned keep);
-
-#define MDBX_SPLIT_REPLACE MDBX_APPENDDUP /* newkey is not new */
-static int __must_check_result mdbx_page_split(MDBX_cursor *mc,
-                                               const MDBX_val *newkey,
-                                               MDBX_val *newdata,
-                                               pgno_t newpgno, unsigned nflags);
-
-static int __must_check_result mdbx_read_header(MDBX_env *env, MDBX_meta *meta,
-                                                uint64_t *filesize,
-                                                const int lck_exclusive);
-static int __must_check_result mdbx_sync_locked(MDBX_env *env, unsigned flags,
-                                                MDBX_meta *const pending);
-static int mdbx_env_close0(MDBX_env *env);
-
-static MDBX_node *mdbx_node_search(MDBX_cursor *mc, const MDBX_val *key,
-                                   int *exactp);
-
-static int __must_check_result mdbx_node_add_branch(MDBX_cursor *mc,
-                                                    unsigned indx,
-                                                    const MDBX_val *key,
-                                                    pgno_t pgno);
-static int __must_check_result mdbx_node_add_leaf(MDBX_cursor *mc,
-                                                  unsigned indx,
-                                                  const MDBX_val *key,
-                                                  MDBX_val *data,
-                                                  unsigned flags);
-static int __must_check_result mdbx_node_add_leaf2(MDBX_cursor *mc,
-                                                   unsigned indx,
-                                                   const MDBX_val *key);
-
-static void mdbx_node_del(MDBX_cursor *mc, size_t ksize);
-static void mdbx_node_shrink(MDBX_page *mp, unsigned indx);
-static int __must_check_result mdbx_node_move(MDBX_cursor *csrc,
-                                              MDBX_cursor *cdst, int fromleft);
-static int __must_check_result mdbx_node_read(MDBX_cursor *mc, MDBX_node *leaf,
-                                              MDBX_val *data,
-                                              const txnid_t pp_txnid);
-static int __must_check_result mdbx_rebalance(MDBX_cursor *mc);
-static int __must_check_result mdbx_update_key(MDBX_cursor *mc,
-                                               const MDBX_val *key);
-
-static void mdbx_cursor_pop(MDBX_cursor *mc);
-static int __must_check_result mdbx_cursor_push(MDBX_cursor *mc, MDBX_page *mp);
-
-static int __must_check_result mdbx_audit_ex(MDBX_txn *txn,
-                                             unsigned retired_stored,
-                                             bool dont_filter_gc);
-
-static int __must_check_result mdbx_page_check(MDBX_cursor *const mc,
-                                               const MDBX_page *const mp,
-                                               unsigned options);
-static int __must_check_result mdbx_cursor_check(MDBX_cursor *mc,
-                                                 unsigned options);
-static int __must_check_result mdbx_cursor_del0(MDBX_cursor *mc);
-static int __must_check_result mdbx_del0(MDBX_txn *txn, MDBX_dbi dbi,
-                                         const MDBX_val *key,
-                                         const MDBX_val *data, unsigned flags);
-#define SIBLING_LEFT 0
-#define SIBLING_RIGHT 2
-static int __must_check_result mdbx_cursor_sibling(MDBX_cursor *mc, int dir);
-static int __must_check_result mdbx_cursor_next(MDBX_cursor *mc, MDBX_val *key,
-                                                MDBX_val *data,
-                                                MDBX_cursor_op op);
-static int __must_check_result mdbx_cursor_prev(MDBX_cursor *mc, MDBX_val *key,
-                                                MDBX_val *data,
-                                                MDBX_cursor_op op);
-static int __must_check_result mdbx_cursor_set(MDBX_cursor *mc, MDBX_val *key,
-                                               MDBX_val *data,
-                                               MDBX_cursor_op op, int *exactp);
-static int __must_check_result mdbx_cursor_first(MDBX_cursor *mc, MDBX_val *key,
-                                                 MDBX_val *data);
-static int __must_check_result mdbx_cursor_last(MDBX_cursor *mc, MDBX_val *key,
-                                                MDBX_val *data);
-
-static int __must_check_result mdbx_cursor_init(MDBX_cursor *mc, MDBX_txn *txn,
-                                                MDBX_dbi dbi);
-static int __must_check_result mdbx_xcursor_init0(MDBX_cursor *mc);
-static int __must_check_result mdbx_xcursor_init1(MDBX_cursor *mc,
-                                                  MDBX_node *node,
-                                                  const MDBX_page *mp);
-static int __must_check_result mdbx_xcursor_init2(MDBX_cursor *mc,
-                                                  MDBX_xcursor *src_mx,
-                                                  bool new_dupdata);
-static void cursor_copy_internal(const MDBX_cursor *csrc, MDBX_cursor *cdst);
-
-static int __must_check_result mdbx_drop0(MDBX_cursor *mc, int subs);
-static int __must_check_result mdbx_fetch_sdb(MDBX_txn *txn, MDBX_dbi dbi);
-static int __must_check_result mdbx_setup_dbx(MDBX_dbx *const dbx,
-                                              const MDBX_db *const db,
-                                              const unsigned pagesize);
-
-static MDBX_cmp_func cmp_lexical, cmp_reverse, cmp_int_align4, cmp_int_align2,
-    cmp_int_unaligned, cmp_lenfast;
-
-static __inline MDBX_cmp_func *get_default_keycmp(unsigned flags);
-static __inline MDBX_cmp_func *get_default_datacmp(unsigned flags);
-
-__cold const char *mdbx_liberr2str(int errnum) {
-  /* Table of descriptions for MDBX errors */
-  static const char *const tbl[] = {
-      "MDBX_KEYEXIST: Key/data pair already exists",
-      "MDBX_NOTFOUND: No matching key/data pair found",
-      "MDBX_PAGE_NOTFOUND: Requested page not found",
-      "MDBX_CORRUPTED: Database is corrupted",
-      "MDBX_PANIC: Environment had fatal error",
-      "MDBX_VERSION_MISMATCH: DB version mismatch libmdbx",
-      "MDBX_INVALID: File is not an MDBX file",
-      "MDBX_MAP_FULL: Environment mapsize limit reached",
-      "MDBX_DBS_FULL: Too many DBI-handles (maxdbs reached)",
-      "MDBX_READERS_FULL: Too many readers (maxreaders reached)",
-      NULL /* MDBX_TLS_FULL (-30789): unused in MDBX */,
-      "MDBX_TXN_FULL: Transaction has too many dirty pages,"
-      " i.e transaction is too big",
-      "MDBX_CURSOR_FULL: Cursor stack limit reachedn - this usually indicates"
-      " corruption, i.e branch-pages loop",
-      "MDBX_PAGE_FULL: Internal error - Page has no more space",
-      "MDBX_UNABLE_EXTEND_MAPSIZE: Database engine was unable to extend"
-      " mapping, e.g. since address space is unavailable or busy,"
-      " or Operation system not supported such operations",
-      "MDBX_INCOMPATIBLE: Environment or database is not compatible"
-      " with the requested operation or the specified flags",
-      "MDBX_BAD_RSLOT: Invalid reuse of reader locktable slot,"
-      " e.g. read-transaction already run for current thread",
-      "MDBX_BAD_TXN: Transaction is not valid for requested operation,"
-      " e.g. had errored and be must aborted, has a child, or is invalid",
-      "MDBX_BAD_VALSIZE: Invalid size or alignment of key or data"
-      " for target database, either invalid subDB name",
-      "MDBX_BAD_DBI: The specified DBI-handle is invalid"
-      " or changed by another thread/transaction",
-      "MDBX_PROBLEM: Unexpected internal error, transaction should be aborted",
-      "MDBX_BUSY: Another write transaction is running,"
-      " or environment is already used while opening with MDBX_EXCLUSIVE flag",
-  };
-
-  if (errnum >= MDBX_KEYEXIST && errnum <= MDBX_BUSY) {
-    int i = errnum - MDBX_KEYEXIST;
-    return tbl[i];
-  }
-
-  switch (errnum) {
-  case MDBX_SUCCESS:
-    return "MDBX_SUCCESS: Successful";
-  case MDBX_EMULTIVAL:
-    return "MDBX_EMULTIVAL: The specified key has"
-           " more than one associated value";
-  case MDBX_EBADSIGN:
-    return "MDBX_EBADSIGN: Wrong signature of a runtime object(s),"
-           " e.g. memory corruption or double-free";
-  case MDBX_WANNA_RECOVERY:
-    return "MDBX_WANNA_RECOVERY: Database should be recovered,"
-           " but this could NOT be done automatically for now"
-           " since it opened in read-only mode";
-  case MDBX_EKEYMISMATCH:
-    return "MDBX_EKEYMISMATCH: The given key value is mismatched to the"
-           " current cursor position";
-  case MDBX_TOO_LARGE:
-    return "MDBX_TOO_LARGE: Database is too large for current system,"
-           " e.g. could NOT be mapped into RAM";
-  case MDBX_THREAD_MISMATCH:
-    return "MDBX_THREAD_MISMATCH: A thread has attempted to use a not"
-           " owned object, e.g. a transaction that started by another thread";
-  case MDBX_TXN_OVERLAPPING:
-    return "MDBX_TXN_OVERLAPPING: Overlapping read and write transactions for"
-           " the current thread";
-  default:
-    return NULL;
-  }
-}
-
-const char *__cold mdbx_strerror_r(int errnum, char *buf, size_t buflen) {
-  const char *msg = mdbx_liberr2str(errnum);
-  if (!msg && buflen > 0 && buflen < INT_MAX) {
-#if defined(_WIN32) || defined(_WIN64)
-    const DWORD size = FormatMessageA(
-        FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL,
-        errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, (DWORD)buflen,
-        NULL);
-    return size ? buf : "FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM) failed";
-#elif defined(_GNU_SOURCE) && defined(__GLIBC__)
-    /* GNU-specific */
-    if (errnum > 0)
-      msg = strerror_r(errnum, buf, buflen);
-#elif (_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600)
-    /* XSI-compliant */
-    if (errnum > 0 && strerror_r(errnum, buf, buflen) == 0)
-      msg = buf;
-#else
-    if (errnum > 0) {
-      msg = strerror(errnum);
-      if (msg) {
-        strncpy(buf, msg, buflen);
-        msg = buf;
-      }
-    }
-#endif
-    if (!msg) {
-      (void)snprintf(buf, buflen, "error %d", errnum);
-      msg = buf;
-    }
-    buf[buflen - 1] = '\0';
-  }
-  return msg;
-}
-
-const char *__cold mdbx_strerror(int errnum) {
-#if defined(_WIN32) || defined(_WIN64)
-  static char buf[1024];
-  return mdbx_strerror_r(errnum, buf, sizeof(buf));
-#else
-  const char *msg = mdbx_liberr2str(errnum);
-  if (!msg) {
-    if (errnum > 0)
-      msg = strerror(errnum);
-    if (!msg) {
-      static char buf[32];
-      (void)snprintf(buf, sizeof(buf) - 1, "error %d", errnum);
-      msg = buf;
-    }
-  }
-  return msg;
-#endif
-}
-
-#if defined(_WIN32) || defined(_WIN64) /* Bit of madness for Windows */
-const char *mdbx_strerror_r_ANSI2OEM(int errnum, char *buf, size_t buflen) {
-  const char *msg = mdbx_liberr2str(errnum);
-  if (!msg && buflen > 0 && buflen < INT_MAX) {
-    const DWORD size = FormatMessageA(
-        FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL,
-        errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, (DWORD)buflen,
-        NULL);
-    if (!size)
-      msg = "FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM) failed";
-    else if (!CharToOemBuffA(buf, buf, size))
-      msg = "CharToOemBuffA() failed";
-    else
-      msg = buf;
-  }
-  return msg;
-}
-
-const char *mdbx_strerror_ANSI2OEM(int errnum) {
-  static char buf[1024];
-  return mdbx_strerror_r_ANSI2OEM(errnum, buf, sizeof(buf));
-}
-#endif /* Bit of madness for Windows */
-
-void __cold mdbx_debug_log_va(int level, const char *function, int line,
-                              const char *fmt, va_list args) {
-  if (mdbx_debug_logger)
-    mdbx_debug_logger(level, function, line, fmt, args);
-  else {
-#if defined(_WIN32) || defined(_WIN64)
-    if (IsDebuggerPresent()) {
-      int prefix_len = 0;
-      char *prefix = nullptr;
-      if (function && line > 0)
-        prefix_len = mdbx_asprintf(&prefix, "%s:%d ", function, line);
-      else if (function)
-        prefix_len = mdbx_asprintf(&prefix, "%s: ", function);
-      else if (line > 0)
-        prefix_len = mdbx_asprintf(&prefix, "%d: ", line);
-      if (prefix_len > 0 && prefix) {
-        OutputDebugStringA(prefix);
-        mdbx_free(prefix);
-      }
-      char *msg = nullptr;
-      int msg_len = mdbx_vasprintf(&msg, fmt, args);
-      if (msg_len > 0 && msg) {
-        OutputDebugStringA(msg);
-        mdbx_free(msg);
-      }
-    }
-#else
-    if (function && line > 0)
-      fprintf(stderr, "%s:%d ", function, line);
-    else if (function)
-      fprintf(stderr, "%s: ", function);
-    else if (line > 0)
-      fprintf(stderr, "%d: ", line);
-    vfprintf(stderr, fmt, args);
-    fflush(stderr);
-#endif
-  }
-}
-
-void __cold mdbx_debug_log(int level, const char *function, int line,
-                           const char *fmt, ...) {
-  va_list args;
-  va_start(args, fmt);
-  mdbx_debug_log_va(level, function, line, fmt, args);
-  va_end(args);
-}
-
-/* Dump a key in ascii or hexadecimal. */
-const char *mdbx_dump_val(const MDBX_val *key, char *const buf,
-                          const size_t bufsize) {
-  if (!key)
-    return "<null>";
-  if (!key->iov_len)
-    return "<empty>";
-  if (!buf || bufsize < 4)
-    return nullptr;
-
-  bool is_ascii = true;
-  const uint8_t *const data = key->iov_base;
-  for (unsigned i = 0; i < key->iov_len; i++)
-    if (data[i] < ' ' || data[i] > '~') {
-      is_ascii = false;
-      break;
-    }
-
-  if (is_ascii) {
-    int len =
-        snprintf(buf, bufsize, "%.*s",
-                 (key->iov_len > INT_MAX) ? INT_MAX : (int)key->iov_len, data);
-    assert(len > 0 && (unsigned)len < bufsize);
-    (void)len;
-  } else {
-    char *const detent = buf + bufsize - 2;
-    char *ptr = buf;
-    *ptr++ = '<';
-    for (unsigned i = 0; i < key->iov_len; i++) {
-      const ptrdiff_t left = detent - ptr;
-      assert(left > 0);
-      int len = snprintf(ptr, left, "%02x", data[i]);
-      if (len < 0 || len >= left)
-        break;
-      ptr += len;
-    }
-    if (ptr < detent) {
-      ptr[0] = '>';
-      ptr[1] = '\0';
-    }
-  }
-  return buf;
-}
-
-/*------------------------------------------------------------------------------
- LY: debug stuff */
-
-static const char *mdbx_leafnode_type(MDBX_node *n) {
-  static const char *const tp[2][2] = {{"", ": DB"},
-                                       {": sub-page", ": sub-DB"}};
-  return F_ISSET(node_flags(n), F_BIGDATA)
-             ? ": overflow page"
-             : tp[F_ISSET(node_flags(n), F_DUPDATA)]
-                 [F_ISSET(node_flags(n), F_SUBDATA)];
-}
-
-/* Display all the keys in the page. */
-static __maybe_unused void mdbx_page_list(MDBX_page *mp) {
-  pgno_t pgno = mp->mp_pgno;
-  const char *type, *state = IS_DIRTY(mp) ? ", dirty" : "";
-  MDBX_node *node;
-  unsigned i, nkeys, nsize, total = 0;
-  MDBX_val key;
-  DKBUF;
-
-  switch (mp->mp_flags &
-          (P_BRANCH | P_LEAF | P_LEAF2 | P_META | P_OVERFLOW | P_SUBP)) {
-  case P_BRANCH:
-    type = "Branch page";
-    break;
-  case P_LEAF:
-    type = "Leaf page";
-    break;
-  case P_LEAF | P_SUBP:
-    type = "Leaf sub-page";
-    break;
-  case P_LEAF | P_LEAF2:
-    type = "Leaf2 page";
-    break;
-  case P_LEAF | P_LEAF2 | P_SUBP:
-    type = "Leaf2 sub-page";
-    break;
-  case P_OVERFLOW:
-    mdbx_verbose("Overflow page %" PRIaPGNO " pages %u%s\n", pgno, mp->mp_pages,
-                 state);
-    return;
-  case P_META:
-    mdbx_verbose("Meta-page %" PRIaPGNO " txnid %" PRIu64 "\n", pgno,
-                 unaligned_peek_u64(4, page_meta(mp)->mm_txnid_a));
-    return;
-  default:
-    mdbx_verbose("Bad page %" PRIaPGNO " flags 0x%X\n", pgno, mp->mp_flags);
-    return;
-  }
-
-  nkeys = page_numkeys(mp);
-  mdbx_verbose("%s %" PRIaPGNO " numkeys %u%s\n", type, pgno, nkeys, state);
-
-  for (i = 0; i < nkeys; i++) {
-    if (IS_LEAF2(mp)) { /* LEAF2 pages have no mp_ptrs[] or node headers */
-      key.iov_len = nsize = mp->mp_leaf2_ksize;
-      key.iov_base = page_leaf2key(mp, i, nsize);
-      total += nsize;
-      mdbx_verbose("key %u: nsize %u, %s\n", i, nsize, DKEY(&key));
-      continue;
-    }
-    node = page_node(mp, i);
-    key.iov_len = node_ks(node);
-    key.iov_base = node->mn_data;
-    nsize = (unsigned)(NODESIZE + key.iov_len);
-    if (IS_BRANCH(mp)) {
-      mdbx_verbose("key %u: page %" PRIaPGNO ", %s\n", i, node_pgno(node),
-                   DKEY(&key));
-      total += nsize;
-    } else {
-      if (F_ISSET(node_flags(node), F_BIGDATA))
-        nsize += sizeof(pgno_t);
-      else
-        nsize += (unsigned)node_ds(node);
-      total += nsize;
-      nsize += sizeof(indx_t);
-      mdbx_verbose("key %u: nsize %u, %s%s\n", i, nsize, DKEY(&key),
-                   mdbx_leafnode_type(node));
-    }
-    total = EVEN(total);
-  }
-  mdbx_verbose("Total: header %u + contents %u + unused %u\n",
-               IS_LEAF2(mp) ? PAGEHDRSZ : PAGEHDRSZ + mp->mp_lower, total,
-               page_room(mp));
-}
-
-/*----------------------------------------------------------------------------*/
-
-/* Check if there is an initialized xcursor, so XCURSOR_REFRESH() is proper */
-#define XCURSOR_INITED(mc)                                                     \
-  ((mc)->mc_xcursor && ((mc)->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED))
-
-/* Update sub-page pointer, if any, in mc->mc_xcursor.
- * Needed when the node which contains the sub-page may have moved.
- * Called with mp = mc->mc_pg[mc->mc_top], ki = mc->mc_ki[mc->mc_top]. */
-#define XCURSOR_REFRESH(mc, mp, ki)                                            \
-  do {                                                                         \
-    MDBX_page *xr_pg = (mp);                                                   \
-    MDBX_node *xr_node = page_node(xr_pg, ki);                                 \
-    if ((node_flags(xr_node) & (F_DUPDATA | F_SUBDATA)) == F_DUPDATA)          \
-      (mc)->mc_xcursor->mx_cursor.mc_pg[0] = node_data(xr_node);               \
-  } while (0)
-
-static __maybe_unused bool cursor_is_tracked(const MDBX_cursor *mc) {
-  for (MDBX_cursor *scan = mc->mc_txn->tw.cursors[mc->mc_dbi]; scan;
-       scan = scan->mc_next)
-    if (mc == ((mc->mc_flags & C_SUB) ? &scan->mc_xcursor->mx_cursor : scan))
-      return true;
-  return false;
-}
-
-/* Perform act while tracking temporary cursor mn */
-#define WITH_CURSOR_TRACKING(mn, act)                                          \
-  do {                                                                         \
-    mdbx_cassert(&(mn),                                                        \
-                 mn.mc_txn->tw.cursors != NULL /* must be not rdonly txt */);  \
-    mdbx_cassert(&(mn), !cursor_is_tracked(&(mn)));                            \
-    MDBX_cursor mc_dummy;                                                      \
-    MDBX_cursor **tracking_head = &(mn).mc_txn->tw.cursors[mn.mc_dbi];         \
-    MDBX_cursor *tracked = &(mn);                                              \
-    if ((mn).mc_flags & C_SUB) {                                               \
-      mc_dummy.mc_flags = C_INITIALIZED;                                       \
-      mc_dummy.mc_top = 0;                                                     \
-      mc_dummy.mc_xcursor = (MDBX_xcursor *)&(mn);                             \
-      tracked = &mc_dummy;                                                     \
-    }                                                                          \
-    tracked->mc_next = *tracking_head;                                         \
-    *tracking_head = tracked;                                                  \
-    { act; }                                                                   \
-    *tracking_head = tracked->mc_next;                                         \
-  } while (0)
-
-int mdbx_cmp(const MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *a,
-             const MDBX_val *b) {
-  mdbx_assert(NULL, txn->mt_signature == MDBX_MT_SIGNATURE);
-  return txn->mt_dbxs[dbi].md_cmp(a, b);
-}
-
-int mdbx_dcmp(const MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *a,
-              const MDBX_val *b) {
-  mdbx_assert(NULL, txn->mt_signature == MDBX_MT_SIGNATURE);
-  return txn->mt_dbxs[dbi].md_dcmp(a, b);
-}
-
-/* Allocate memory for a page.
- * Re-use old malloc'd pages first for singletons, otherwise just malloc.
- * Set MDBX_TXN_ERROR on failure. */
-static MDBX_page *mdbx_page_malloc(MDBX_txn *txn, unsigned num) {
-  MDBX_env *env = txn->mt_env;
-  MDBX_page *np = env->me_dp_reserve;
-  size_t size = env->me_psize;
-  if (likely(num == 1 && np)) {
-    mdbx_assert(env, env->me_dp_reserve_len > 0);
-    ASAN_UNPOISON_MEMORY_REGION(np, size);
-    VALGRIND_MEMPOOL_ALLOC(env, np, size);
-    VALGRIND_MAKE_MEM_DEFINED(&np->mp_next, sizeof(np->mp_next));
-    env->me_dp_reserve = np->mp_next;
-    env->me_dp_reserve_len -= 1;
-  } else {
-    size = pgno2bytes(env, num);
-    np = mdbx_malloc(size);
-    if (unlikely(!np)) {
-      txn->mt_flags |= MDBX_TXN_ERROR;
-      return np;
-    }
-    VALGRIND_MEMPOOL_ALLOC(env, np, size);
-  }
-
-  if ((env->me_flags & MDBX_NOMEMINIT) == 0) {
-    /* For a single page alloc, we init everything after the page header.
-     * For multi-page, we init the final page; if the caller needed that
-     * many pages they will be filling in at least up to the last page. */
-    size_t skip = PAGEHDRSZ;
-    if (num > 1)
-      skip += pgno2bytes(env, num - 1);
-    memset((char *)np + skip, 0, size - skip);
-  }
-#if MDBX_DEBUG
-  np->mp_pgno = 0;
-#endif
-  VALGRIND_MAKE_MEM_UNDEFINED(np, size);
-  np->mp_flags = 0;
-  np->mp_pages = num;
-  return np;
-}
-
-/* Free a shadow dirty page */
-static void mdbx_dpage_free(MDBX_env *env, MDBX_page *dp, unsigned npages) {
-  VALGRIND_MAKE_MEM_UNDEFINED(dp, pgno2bytes(env, npages));
-  ASAN_UNPOISON_MEMORY_REGION(dp, pgno2bytes(env, npages));
-  if (MDBX_DEBUG || unlikely(env->me_flags & MDBX_PAGEPERTURB))
-    memset(dp, -1, pgno2bytes(env, npages));
-  if (npages == 1 &&
-      env->me_dp_reserve_len < env->me_options.dp_reserve_limit) {
-    ASAN_POISON_MEMORY_REGION((char *)dp + sizeof(dp->mp_next),
-                              pgno2bytes(env, npages) - sizeof(dp->mp_next));
-    dp->mp_next = env->me_dp_reserve;
-    VALGRIND_MEMPOOL_FREE(env, dp);
-    env->me_dp_reserve = dp;
-    env->me_dp_reserve_len += 1;
-  } else {
-    /* large pages just get freed directly */
-    VALGRIND_MEMPOOL_FREE(env, dp);
-    mdbx_free(dp);
-  }
-}
-
-/* Return all dirty pages to dpage list */
-static void mdbx_dlist_free(MDBX_txn *txn) {
-  MDBX_env *env = txn->mt_env;
-  MDBX_dpl *const dl = txn->tw.dirtylist;
-  const size_t len = dl->length;
-
-  for (size_t i = 1; i <= len; i++) {
-    MDBX_page *dp = dl->items[i].ptr;
-    mdbx_dpage_free(env, dp, IS_OVERFLOW(dp) ? dp->mp_pages : 1);
-  }
-
-  mdbx_dpl_clear(dl);
-}
-
-static __always_inline MDBX_db *mdbx_outer_db(MDBX_cursor *mc) {
-  mdbx_cassert(mc, (mc->mc_flags & C_SUB) != 0);
-  MDBX_xcursor *mx = container_of(mc->mc_db, MDBX_xcursor, mx_db);
-  MDBX_cursor_couple *couple = container_of(mx, MDBX_cursor_couple, inner);
-  mdbx_cassert(mc, mc->mc_db == &couple->outer.mc_xcursor->mx_db);
-  mdbx_cassert(mc, mc->mc_dbx == &couple->outer.mc_xcursor->mx_dbx);
-  return couple->outer.mc_db;
-}
-
-static __cold __maybe_unused bool mdbx_dirtylist_check(MDBX_txn *txn) {
-  if (!mdbx_audit_enabled())
-    return true;
-
-  const MDBX_dpl *const dl = txn->tw.dirtylist;
-  unsigned loose = 0;
-  for (unsigned i = dl->length; i > 0; --i) {
-    const MDBX_page *const dp = dl->items[i].ptr;
-    if (!dp)
-      continue;
-
-    mdbx_tassert(txn, dp->mp_pgno == dl->items[i].pgno);
-    if (unlikely(dp->mp_pgno != dl->items[i].pgno))
-      return false;
-
-    mdbx_tassert(txn, dp->mp_flags & P_DIRTY);
-    if (unlikely((dp->mp_flags & P_DIRTY) == 0))
-      return false;
-    if (dp->mp_flags & P_LOOSE) {
-      mdbx_tassert(txn, dp->mp_flags == (P_LOOSE | P_DIRTY));
-      if (unlikely(dp->mp_flags != (P_LOOSE | P_DIRTY)))
-        return false;
-      loose += 1;
-    }
-
-    const unsigned num = IS_OVERFLOW(dp) ? dp->mp_pages : 1;
-    mdbx_tassert(txn, txn->mt_next_pgno >= dp->mp_pgno + num);
-    if (unlikely(txn->mt_next_pgno < dp->mp_pgno + num))
-      return false;
-
-    if (i < dl->sorted) {
-      mdbx_tassert(txn, dl->items[i + 1].pgno >= dp->mp_pgno + num);
-      if (unlikely(dl->items[i + 1].pgno < dp->mp_pgno + num))
-        return false;
-    }
-
-    const unsigned rpa = mdbx_pnl_search(txn->tw.reclaimed_pglist, dp->mp_pgno);
-    mdbx_tassert(txn, rpa > MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) ||
-                          txn->tw.reclaimed_pglist[rpa] != dp->mp_pgno);
-    if (rpa <= MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) &&
-        unlikely(txn->tw.reclaimed_pglist[rpa] == dp->mp_pgno))
-      return false;
-    if (num > 1) {
-      const unsigned rpb =
-          mdbx_pnl_search(txn->tw.reclaimed_pglist, dp->mp_pgno + num - 1);
-      mdbx_tassert(txn, rpa == rpb);
-      if (unlikely(rpa != rpb))
-        return false;
-    }
-  }
-
-  mdbx_tassert(txn, loose == txn->tw.loose_count);
-  if (unlikely(loose != txn->tw.loose_count))
-    return false;
-
-  for (unsigned i = 1; i <= MDBX_PNL_SIZE(txn->tw.retired_pages); ++i) {
-    const MDBX_page *const dp = debug_dpl_find(dl, txn->tw.retired_pages[i]);
-    mdbx_tassert(txn, !dp);
-    if (unlikely(dp))
-      return false;
-  }
-
-  return true;
-}
-
-#if MDBX_ENABLE_REFUND
-static void mdbx_refund_reclaimed(MDBX_txn *txn) {
-  /* Scanning in descend order */
-  pgno_t next_pgno = txn->mt_next_pgno;
-  const MDBX_PNL pnl = txn->tw.reclaimed_pglist;
-  mdbx_tassert(txn, MDBX_PNL_SIZE(pnl) && MDBX_PNL_MOST(pnl) == next_pgno - 1);
-#if MDBX_PNL_ASCENDING
-  unsigned i = MDBX_PNL_SIZE(pnl);
-  mdbx_tassert(txn, pnl[i] == next_pgno - 1);
-  while (--next_pgno, --i > 0 && pnl[i] == next_pgno - 1)
-    ;
-  MDBX_PNL_SIZE(pnl) = i;
-#else
-  unsigned i = 1;
-  mdbx_tassert(txn, pnl[i] == next_pgno - 1);
-  unsigned len = MDBX_PNL_SIZE(pnl);
-  while (--next_pgno, ++i <= len && pnl[i] == next_pgno - 1)
-    ;
-  MDBX_PNL_SIZE(pnl) = len -= i - 1;
-  for (unsigned move = 0; move < len; ++move)
-    pnl[1 + move] = pnl[i + move];
-#endif
-  mdbx_verbose("refunded %" PRIaPGNO " pages: %" PRIaPGNO " -> %" PRIaPGNO,
-               txn->mt_next_pgno - next_pgno, txn->mt_next_pgno, next_pgno);
-  txn->mt_next_pgno = next_pgno;
-  mdbx_tassert(txn, mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                          txn->mt_next_pgno - 1));
-}
-
-static void mdbx_refund_loose(MDBX_txn *txn) {
-  mdbx_tassert(txn, txn->tw.loose_pages != nullptr);
-  mdbx_tassert(txn, txn->tw.loose_count > 0);
-
-  MDBX_dpl *const dl = txn->tw.dirtylist;
-  mdbx_tassert(txn, dl->length >= txn->tw.loose_count);
-
-  pgno_t onstack[MDBX_CACHELINE_SIZE * 8 / sizeof(pgno_t)];
-  MDBX_PNL suitable = onstack;
-
-  if (dl->length - dl->sorted > txn->tw.loose_count) {
-    /* Dirty list is useless since unsorted. */
-    if (bytes2pnl(sizeof(onstack)) < txn->tw.loose_count) {
-      suitable = mdbx_pnl_alloc(txn->tw.loose_count);
-      if (unlikely(!suitable))
-        return /* this is not a reason for transaction fail */;
-    }
-
-    /* Collect loose-pages which may be refunded. */
-    mdbx_tassert(txn, txn->mt_next_pgno >= MIN_PAGENO + txn->tw.loose_count);
-    pgno_t most = MIN_PAGENO;
-    unsigned w = 0;
-    for (const MDBX_page *lp = txn->tw.loose_pages; lp; lp = lp->mp_next) {
-      mdbx_tassert(txn, lp->mp_flags == (P_LOOSE | P_DIRTY));
-      mdbx_tassert(txn, txn->mt_next_pgno > lp->mp_pgno);
-      if (likely(txn->mt_next_pgno - txn->tw.loose_count <= lp->mp_pgno)) {
-        mdbx_tassert(txn,
-                     w < ((suitable == onstack) ? bytes2pnl(sizeof(onstack))
-                                                : MDBX_PNL_ALLOCLEN(suitable)));
-        suitable[++w] = lp->mp_pgno;
-        most = (lp->mp_pgno > most) ? lp->mp_pgno : most;
-      }
-    }
-
-    if (most + 1 == txn->mt_next_pgno) {
-      /* Sort suitable list and refund pages at the tail. */
-      MDBX_PNL_SIZE(suitable) = w;
-      mdbx_pnl_sort(suitable);
-
-      /* Scanning in descend order */
-      const int step = MDBX_PNL_ASCENDING ? -1 : 1;
-      const int begin = MDBX_PNL_ASCENDING ? MDBX_PNL_SIZE(suitable) : 1;
-      const int end = MDBX_PNL_ASCENDING ? 0 : MDBX_PNL_SIZE(suitable) + 1;
-      mdbx_tassert(txn, suitable[begin] >= suitable[end - step]);
-      mdbx_tassert(txn, most == suitable[begin]);
-
-      for (int i = begin + step; i != end; i += step) {
-        if (suitable[i] != most - 1)
-          break;
-        most -= 1;
-      }
-      const unsigned refunded = txn->mt_next_pgno - most;
-      mdbx_debug("refund-suitable %u pages %" PRIaPGNO " -> %" PRIaPGNO,
-                 refunded, most, txn->mt_next_pgno);
-      txn->tw.loose_count -= refunded;
-      txn->tw.dirtyroom += refunded;
-      assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-      txn->mt_next_pgno = most;
-
-      /* Filter-out dirty list */
-      unsigned r = 0;
-      w = 0;
-      if (dl->sorted) {
-        do {
-          if (dl->items[++r].pgno < most) {
-            if (++w != r)
-              dl->items[w] = dl->items[r];
-          }
-        } while (r < dl->sorted);
-        dl->sorted = w;
-      }
-      while (r < dl->length) {
-        if (dl->items[++r].pgno < most) {
-          if (++w != r)
-            dl->items[w] = dl->items[r];
-        }
-      }
-      dl->length = w;
-      mdbx_tassert(txn, txn->mt_parent || txn->tw.dirtyroom + dl->length ==
-                                              txn->mt_env->me_options.dp_limit);
-      goto unlink_loose;
-    }
-  } else {
-    /* Dirtylist is mostly sorted, just refund loose pages at the end. */
-    mdbx_dpl_sort(dl);
-    mdbx_tassert(txn, dl->length < 2 ||
-                          dl->items[1].pgno < dl->items[dl->length].pgno);
-    mdbx_tassert(txn, dl->sorted == dl->length);
-
-    /* Scan dirtylist tail-forward and cutoff suitable pages. */
-    while (dl->length && dl->items[dl->length].pgno == txn->mt_next_pgno - 1 &&
-           dl->items[dl->length].ptr->mp_flags == (P_LOOSE | P_DIRTY)) {
-      MDBX_page *dp = dl->items[dl->length].ptr;
-      mdbx_debug("refund-sorted page %" PRIaPGNO, dp->mp_pgno);
-      mdbx_tassert(txn, dp->mp_pgno == dl->items[dl->length].pgno);
-      txn->mt_next_pgno -= 1;
-      dl->length -= 1;
-    }
-
-    if (dl->sorted != dl->length) {
-      const unsigned refunded = dl->sorted - dl->length;
-      dl->sorted = dl->length;
-      txn->tw.loose_count -= refunded;
-      txn->tw.dirtyroom += refunded;
-      mdbx_tassert(txn, txn->mt_parent || txn->tw.dirtyroom + dl->length ==
-                                              txn->mt_env->me_options.dp_limit);
-      assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-
-      /* Filter-out loose chain & dispose refunded pages. */
-    unlink_loose:
-      for (MDBX_page **link = &txn->tw.loose_pages; *link;) {
-        MDBX_page *dp = *link;
-        mdbx_tassert(txn, dp->mp_flags == (P_LOOSE | P_DIRTY));
-        if (txn->mt_next_pgno > dp->mp_pgno) {
-          link = &dp->mp_next;
-        } else {
-          *link = dp->mp_next;
-          if ((txn->mt_flags & MDBX_WRITEMAP) == 0)
-            mdbx_dpage_free(txn->mt_env, dp, 1);
-        }
-      }
-    }
-  }
-
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  mdbx_tassert(txn, txn->mt_parent || txn->tw.dirtyroom + dl->length ==
-                                          txn->mt_env->me_options.dp_limit);
-  if (suitable != onstack)
-    mdbx_pnl_free(suitable);
-  txn->tw.loose_refund_wl = txn->mt_next_pgno;
-}
-
-static bool mdbx_refund(MDBX_txn *txn) {
-  const pgno_t before = txn->mt_next_pgno;
-
-  if (txn->tw.loose_pages && txn->tw.loose_refund_wl > txn->mt_next_pgno)
-    mdbx_refund_loose(txn);
-
-  while (true) {
-    if (MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) == 0 ||
-        MDBX_PNL_MOST(txn->tw.reclaimed_pglist) != txn->mt_next_pgno - 1)
-      break;
-
-    mdbx_refund_reclaimed(txn);
-    if (!txn->tw.loose_pages || txn->tw.loose_refund_wl <= txn->mt_next_pgno)
-      break;
-
-    const pgno_t memo = txn->mt_next_pgno;
-    mdbx_refund_loose(txn);
-    if (memo == txn->mt_next_pgno)
-      break;
-  }
-
-  if (before == txn->mt_next_pgno)
-    return false;
-
-  if (txn->tw.spill_pages)
-    /* Squash deleted pagenums if we refunded any */
-    mdbx_spill_purge(txn);
-
-  return true;
-}
-#else  /* MDBX_ENABLE_REFUND */
-static __inline bool mdbx_refund(MDBX_txn *txn) {
-  (void)txn;
-  /* No online auto-compactification. */
-  return false;
-}
-#endif /* MDBX_ENABLE_REFUND */
-
-static __cold void mdbx_kill_page(MDBX_env *env, MDBX_page *mp, pgno_t pgno,
-                                  unsigned npages) {
-  mdbx_debug("kill%s %u page %" PRIaPGNO, IS_DIRTY(mp) ? " dirty" : "", npages,
-             pgno);
-  mdbx_assert(env, pgno >= NUM_METAS && npages);
-  if (IS_DIRTY(mp) || (env->me_flags & MDBX_WRITEMAP)) {
-    const size_t bytes = pgno2bytes(env, npages);
-    memset(mp, -1, bytes);
-    mp->mp_pgno = pgno;
-    if ((env->me_flags & MDBX_WRITEMAP) == 0)
-      mdbx_pwrite(env->me_lazy_fd, mp, bytes, pgno2bytes(env, pgno));
-  } else {
-    struct iovec iov[MDBX_COMMIT_PAGES];
-    iov[0].iov_len = env->me_psize;
-    iov[0].iov_base = (char *)env->me_pbuf + env->me_psize;
-    size_t iov_off = pgno2bytes(env, pgno);
-    unsigned n = 1;
-    while (--npages) {
-      iov[n] = iov[0];
-      if (++n == MDBX_COMMIT_PAGES) {
-        mdbx_pwritev(env->me_lazy_fd, iov, MDBX_COMMIT_PAGES, iov_off,
-                     pgno2bytes(env, MDBX_COMMIT_PAGES));
-        iov_off += pgno2bytes(env, MDBX_COMMIT_PAGES);
-        n = 0;
-      }
-    }
-    mdbx_pwritev(env->me_lazy_fd, iov, n, iov_off, pgno2bytes(env, n));
-  }
-}
-
-/* Remove page from dirty list */
-static __inline void mdbx_page_wash(MDBX_txn *txn, const unsigned di,
-                                    MDBX_page *const mp,
-                                    const unsigned npages) {
-  mdbx_tassert(txn, di && di <= txn->tw.dirtylist->length &&
-                        txn->tw.dirtylist->items[di].ptr == mp);
-  mdbx_dpl_remove(txn->tw.dirtylist, di);
-  txn->tw.dirtyroom++;
-  assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-  mdbx_tassert(txn, txn->mt_parent ||
-                        txn->tw.dirtyroom + txn->tw.dirtylist->length ==
-                            txn->mt_env->me_options.dp_limit);
-  mp->mp_txnid = INVALID_TXNID;
-  mp->mp_flags = 0xFFFF;
-  VALGRIND_MAKE_MEM_UNDEFINED(mp, PAGEHDRSZ);
-  if (txn->mt_flags & MDBX_WRITEMAP) {
-    VALGRIND_MAKE_MEM_NOACCESS(page_data(mp),
-                               pgno2bytes(txn->mt_env, npages) - PAGEHDRSZ);
-    ASAN_POISON_MEMORY_REGION(page_data(mp),
-                              pgno2bytes(txn->mt_env, npages) - PAGEHDRSZ);
-  } else
-    mdbx_dpage_free(txn->mt_env, mp, npages);
-}
-
-/* Retire, loosen or free a single page.
- *
- * Saves single pages to a list for future reuse
- * in this same txn. It has been pulled from the GC
- * and already resides on the dirty list, but has been
- * deleted. Use these pages first before pulling again
- * from the GC.
- *
- * If the page wasn't dirtied in this txn, just add it
- * to this txn's free list. */
-static int mdbx_page_loose(MDBX_txn *txn, MDBX_page *mp) {
-  const unsigned npages = IS_OVERFLOW(mp) ? mp->mp_pages : 1;
-  const pgno_t pgno = mp->mp_pgno;
-  const bool is_dirty = IS_DIRTY(mp);
-
-  if (is_dirty) {
-    mdbx_tassert(txn, !txn->tw.spill_pages ||
-                          !mdbx_pnl_exist(txn->tw.spill_pages, pgno << 1));
-    mdbx_tassert(txn, debug_dpl_find(txn->tw.dirtylist, pgno) == mp ||
-                          txn->mt_parent);
-  } else {
-    mdbx_tassert(txn, !debug_dpl_find(txn->tw.dirtylist, pgno));
-  }
-
-  const unsigned di = is_dirty ? mdbx_dpl_exist(txn->tw.dirtylist, pgno) : 0;
-  const unsigned si = (!is_dirty && txn->tw.spill_pages)
-                          ? mdbx_pnl_exist(txn->tw.spill_pages, pgno << 1)
-                          : 0;
-
-  if (MDBX_ENABLE_REFUND && unlikely(pgno + npages == txn->mt_next_pgno)) {
-    const char *kind;
-    if (di) {
-      mdbx_tassert(txn, txn->tw.dirtylist->items[di].ptr == mp);
-      if (unlikely(txn->tw.dirtylist->items[di].ptr != mp)) {
-      wrong_dirty:
-        mdbx_error("wrong dirty page 0x%p #%" PRIaPGNO,
-                   __Wpedantic_format_voidptr(mp), pgno);
-        txn->mt_flags |= MDBX_TXN_ERROR;
-        return MDBX_PROBLEM;
-      }
-      /* Страница испачкана в этой транзакции, но до этого могла быть
-       * аллоцирована, испачкана и пролита в одной из родительских транзакций.
-       * Её МОЖНО вытолкнуть в нераспределенный хвост. */
-      kind = "dirty";
-      /* Remove from dirty list */
-      mdbx_page_wash(txn, di, mp, npages);
-    } else if (is_dirty) {
-      /* The page MUST BE from parent transaction. */
-      if (mdbx_audit_enabled()) {
-        const MDBX_page *parent_dp = nullptr;
-        for (MDBX_txn *parent = txn->mt_parent; parent && !parent_dp;
-             parent = parent->mt_parent) {
-          mdbx_tassert(txn,
-                       !parent->tw.spill_pages ||
-                           !mdbx_pnl_exist(parent->tw.spill_pages, pgno << 1));
-          parent_dp = debug_dpl_find(parent->tw.dirtylist, pgno);
-        }
-        mdbx_tassert(txn, parent_dp == mp);
-      }
-      kind = "parent-dirty";
-    } else if (si) {
-      /* Страница пролита в этой транзакции, следовательно она аллоцирована
-       * и запачкана в этой или одной из родительских транзакций.
-       * Её МОЖНО вытолкнуть в нераспределенный хвост. */
-      kind = "spilled";
-      mdbx_spill_remove(txn, si, npages);
-    } else {
-      for (MDBX_txn *parent = txn->mt_parent;
-           parent && (parent->mt_flags & MDBX_TXN_SPILLS);
-           parent = parent->mt_parent)
-        if (parent->tw.spill_pages &&
-            mdbx_pnl_exist(parent->tw.spill_pages, pgno << 1)) {
-          /* Страница аллоцирована, запачкана и пролита в одной из родительских
-           * транзакций. Её МОЖНО вытолкнуть в нераспределенный хвост. */
-          kind = "parent-spilled";
-          goto refund;
-        }
-      /* Страница используется (входит в MVCC-снимки доступные читателям).
-       * Её НЕЛЬЗЯ вытолкнуть в нераспределенных хвост. */
-      goto retire;
-    }
-  refund:
-    mdbx_debug("refunded %u %s page %" PRIaPGNO, npages, kind, pgno);
-    txn->mt_next_pgno = pgno;
-    mdbx_refund(txn);
-    return MDBX_SUCCESS;
-  }
-
-  if (is_dirty) {
-    if (di) {
-      /* Dirty page from this transaction */
-      mdbx_tassert(txn, txn->tw.dirtylist->items[di].ptr == mp);
-      if (unlikely(txn->tw.dirtylist->items[di].ptr != mp))
-        goto wrong_dirty;
-
-      /* If suitable we can reuse it through loose list */
-      if (likely(
-              npages == 1 &&
-              txn->tw.loose_count < txn->mt_env->me_options.dp_loose_limit &&
-              (!MDBX_ENABLE_REFUND ||
-               /* skip pages near to the end in favor of compactification */
-               txn->mt_next_pgno >
-                   pgno + txn->mt_env->me_options.dp_loose_limit ||
-               txn->mt_next_pgno <= txn->mt_env->me_options.dp_loose_limit))) {
-        mdbx_debug("loosen dirty page %" PRIaPGNO, pgno);
-        mp->mp_flags = P_LOOSE | P_DIRTY;
-        mp->mp_next = txn->tw.loose_pages;
-        txn->tw.loose_pages = mp;
-        txn->tw.loose_count++;
-#if MDBX_ENABLE_REFUND
-        txn->tw.loose_refund_wl = (pgno + 2 > txn->tw.loose_refund_wl)
-                                      ? pgno + 2
-                                      : txn->tw.loose_refund_wl;
-#endif /* MDBX_ENABLE_REFUND */
-        if (MDBX_DEBUG || unlikely(txn->mt_env->me_flags & MDBX_PAGEPERTURB))
-          memset(page_data(mp), -1, txn->mt_env->me_psize - PAGEHDRSZ);
-        VALGRIND_MAKE_MEM_NOACCESS(page_data(mp),
-                                   txn->mt_env->me_psize - PAGEHDRSZ);
-        ASAN_POISON_MEMORY_REGION(page_data(mp),
-                                  txn->mt_env->me_psize - PAGEHDRSZ);
-        return MDBX_SUCCESS;
-      }
-
-#if !MDBX_DEBUG && !defined(MDBX_USE_VALGRIND) && !defined(__SANITIZE_ADDRESS__)
-      if (unlikely(txn->mt_env->me_flags & MDBX_PAGEPERTURB))
-#endif
-      {
-        /* Страница могла быть изменена в одной из родительских транзакций,
-         * в том числе, позже выгружена и затем снова загружена и изменена.
-         * В обоих случаях её нельзя затирать на диске и помечать недоступной
-         * в asan и/или valgrind */
-        for (MDBX_txn *parent = txn->mt_parent;
-             parent && (parent->mt_flags & MDBX_TXN_SPILLS);
-             parent = parent->mt_parent) {
-          if (parent->tw.spill_pages &&
-              mdbx_pnl_intersect(parent->tw.spill_pages, pgno << 1,
-                                 npages << 1))
-            goto skip_invalidate;
-          if (mdbx_dpl_intersect(parent->tw.dirtylist, pgno, npages))
-            goto skip_invalidate;
-        }
-
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-        if (MDBX_DEBUG || unlikely(txn->mt_env->me_flags & MDBX_PAGEPERTURB))
-#endif
-          mdbx_kill_page(txn->mt_env, mp, pgno, npages);
-        if (!(txn->mt_flags & MDBX_WRITEMAP)) {
-          VALGRIND_MAKE_MEM_NOACCESS(page_data(pgno2page(txn->mt_env, pgno)),
-                                     pgno2bytes(txn->mt_env, npages) -
-                                         PAGEHDRSZ);
-          ASAN_POISON_MEMORY_REGION(page_data(pgno2page(txn->mt_env, pgno)),
-                                    pgno2bytes(txn->mt_env, npages) -
-                                        PAGEHDRSZ);
-        }
-      }
-    skip_invalidate:
-      /* Remove from dirty list */
-      mdbx_page_wash(txn, di, mp, npages);
-    } else {
-      /* Dirty page MUST BE a clone from (one of) parent transaction(s). */
-      if (mdbx_audit_enabled()) {
-        const MDBX_page *parent_dp = nullptr;
-        /* Check parent(s)'s dirty lists. */
-        for (MDBX_txn *parent = txn->mt_parent; parent && !parent_dp;
-             parent = parent->mt_parent) {
-          mdbx_tassert(txn,
-                       !parent->tw.spill_pages ||
-                           !mdbx_pnl_exist(parent->tw.spill_pages, pgno << 1));
-          parent_dp = debug_dpl_find(parent->tw.dirtylist, pgno);
-        }
-        mdbx_tassert(txn, parent_dp == mp);
-      }
-    }
-
-  reclaim:
-    mdbx_debug("reclaim %u %s page %" PRIaPGNO, npages, "dirty", pgno);
-    int rc = mdbx_pnl_insert_range(&txn->tw.reclaimed_pglist, pgno, npages);
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-    mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-    return rc;
-  }
-
-  if (si) {
-    /* Page ws spilled in this txn */
-    mdbx_spill_remove(txn, si, npages);
-    /* Страница могла быть выделена и затем пролита в этой транзакции,
-     * тогда её необходимо поместить в reclaimed-список.
-     * Либо она могла быть выделена в одной из родительских транзакций и затем
-     * пролита в этой транзакции, тогда её необходимо поместить в retired-список
-     * для последующей фильтрации при коммите. */
-    for (MDBX_txn *parent = txn->mt_parent; parent;
-         parent = parent->mt_parent) {
-      if (mdbx_dpl_exist(parent->tw.dirtylist, pgno))
-        goto retire;
-    }
-    /* Страница точно была выделена в этой транзакции
-     * и теперь может быть использована повторно. */
-    goto reclaim;
-  } else {
-    /* Страница может входить в доступный читателям MVCC-снимок, либо же она
-     * могла быть выделена, а затем пролита в одной из родительских транзакций.
-     * Поэтому пока помещаем её в retired-список, который будет фильтроваться
-     * относительно dirty- и spilled-списков родительских транзакций при коммите
-     * дочерних транзакций, либо же будет записан в GC в неизменном виде. */
-  }
-
-retire:
-  mdbx_debug("retire %u page %" PRIaPGNO, npages, pgno);
-  int rc = mdbx_pnl_append_range(false, &txn->tw.retired_pages, pgno, npages);
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  return rc;
-}
-
-static int mdbx_page_retire(MDBX_cursor *mc, MDBX_page *mp) {
-  if (unlikely(mc->mc_flags & C_SUB)) {
-    MDBX_db *outer = mdbx_outer_db(mc);
-    mdbx_cassert(mc, !IS_BRANCH(mp) || outer->md_branch_pages > 0);
-    outer->md_branch_pages -= IS_BRANCH(mp);
-    mdbx_cassert(mc, !IS_LEAF(mp) || outer->md_leaf_pages > 0);
-    outer->md_leaf_pages -= IS_LEAF(mp);
-    mdbx_cassert(mc, !IS_OVERFLOW(mp));
-  }
-  mdbx_cassert(mc, !IS_BRANCH(mp) || mc->mc_db->md_branch_pages > 0);
-  mc->mc_db->md_branch_pages -= IS_BRANCH(mp);
-  mdbx_cassert(mc, !IS_LEAF(mp) || mc->mc_db->md_leaf_pages > 0);
-  mc->mc_db->md_leaf_pages -= IS_LEAF(mp);
-  mdbx_cassert(mc, !IS_OVERFLOW(mp) ||
-                       mc->mc_db->md_overflow_pages >= mp->mp_pages);
-  mc->mc_db->md_overflow_pages -= IS_OVERFLOW(mp) ? mp->mp_pages : 0;
-  return mdbx_page_loose(mc->mc_txn, mp);
-}
-
-static __must_check_result __always_inline int
-mdbx_retire_pgno(MDBX_cursor *mc, const pgno_t pgno) {
-  MDBX_page *mp;
-  int rc;
-  if (mdbx_audit_enabled()) {
-    const unsigned save_flags = mc->mc_flags;
-    mc->mc_flags |= C_RETIRING;
-    rc = mdbx_page_get(mc, pgno, &mp, NULL, mc->mc_txn->mt_txnid);
-    if (likely(rc == MDBX_SUCCESS))
-      rc = mdbx_page_retire(mc, mp);
-    mc->mc_flags = (mc->mc_flags & ~C_RETIRING) | (save_flags & C_RETIRING);
-  } else {
-    rc = mdbx_page_get(mc, pgno, &mp, NULL, mc->mc_txn->mt_txnid);
-    if (likely(rc == MDBX_SUCCESS))
-      rc = mdbx_page_retire(mc, mp);
-  }
-  return rc;
-}
-
-/* Toggle P_KEEP in dirty, non-overflow, non-sub pages watched by txn.
- *
- * [in] mc      A cursor handle for the current operation.
- * [in] pflags  Flags of the pages to update:
- *                - P_DIRTY to set P_KEEP,
- *                - P_DIRTY|P_KEEP to clear it. */
-static void mdbx_cursor_xkeep(MDBX_cursor *mc, unsigned pflags) {
-  const unsigned mask = P_SUBP | P_DIRTY | P_LOOSE | P_KEEP;
-  if (mc->mc_flags & C_INITIALIZED) {
-    MDBX_cursor *m3 = mc;
-    for (;;) {
-      MDBX_page *mp = NULL;
-      for (unsigned j = 0; j < m3->mc_snum; j++) {
-        mp = m3->mc_pg[j];
-        if ((mp->mp_flags & mask) == pflags)
-          mp->mp_flags ^= P_KEEP;
-      }
-      if (!(mp && IS_LEAF(mp)))
-        break;
-      /* Proceed to mx if it is at a sub-database */
-      MDBX_xcursor *mx = m3->mc_xcursor;
-      if (!(mx && (mx->mx_cursor.mc_flags & C_INITIALIZED)))
-        break;
-      const unsigned nkeys = page_numkeys(mp);
-      unsigned ki = m3->mc_ki[m3->mc_top];
-      mdbx_cassert(mc, nkeys > 0 &&
-                           (ki < nkeys ||
-                            (ki == nkeys && (mx->mx_cursor.mc_flags & C_EOF))));
-      ki -= ki >= nkeys;
-      if (!(node_flags(page_node(mp, ki)) & F_SUBDATA))
-        break;
-      m3 = &mx->mx_cursor;
-    }
-  }
-}
-
-/* Mark pages seen by cursors: First m0, then tracked cursors
- * [in] all     No shortcuts. Needed except after a full mdbx_page_flush(). */
-static void mdbx_txn_xkeep(MDBX_txn *txn, MDBX_cursor *m0,
-                           const unsigned pflags, const bool all) {
-  if (m0)
-    mdbx_cursor_xkeep(m0, pflags);
-
-  for (unsigned i = FREE_DBI; i < txn->mt_numdbs; ++i)
-    if (txn->mt_dbistate[i] & DBI_DIRTY)
-      for (MDBX_cursor *mc = txn->tw.cursors[i]; mc; mc = mc->mc_next)
-        if (mc != m0)
-          mdbx_cursor_xkeep(mc, pflags);
-
-  if (all) {
-    /* Mark dirty root pages */
-    const unsigned mask = P_SUBP | P_DIRTY | P_LOOSE | P_KEEP;
-    for (unsigned i = 0; i < txn->mt_numdbs; i++) {
-      if (txn->mt_dbistate[i] & DBI_DIRTY) {
-        pgno_t pgno = txn->mt_dbs[i].md_root;
-        if (pgno == P_INVALID)
-          continue;
-        MDBX_page *dp = mdbx_dpl_find(txn->tw.dirtylist, pgno);
-        if (dp && (dp->mp_flags & mask) == pflags)
-          dp->mp_flags ^= P_KEEP;
-      }
-    }
-  }
-}
-
-/* Spill pages from the dirty list back to disk.
- * This is intended to prevent running into MDBX_TXN_FULL situations,
- * but note that they may still occur in a few cases:
- *
- * 1) our estimate of the txn size could be too small. Currently this
- *  seems unlikely, except with a large number of MDBX_MULTIPLE items.
- *
- * 2) child txns may run out of space if their parents dirtied a
- *  lot of pages and never spilled them. TODO: we probably should do
- *  a preemptive spill during mdbx_txn_begin() of a child txn, if
- *  the parent's dirtyroom is below a given threshold.
- *
- * Otherwise, if not using nested txns, it is expected that apps will
- * not run into MDBX_TXN_FULL any more. The pages are flushed to disk
- * the same way as for a txn commit, e.g. their P_DIRTY flag is cleared.
- * If the txn never references them again, they can be left alone.
- * If the txn only reads them, they can be used without any fuss.
- * If the txn writes them again, they can be dirtied immediately without
- * going thru all of the work of mdbx_page_touch(). Such references are
- * handled by mdbx_page_unspill().
- *
- * Also note, we never spill DB root pages, nor pages of active cursors,
- * because we'll need these back again soon anyway. And in nested txns,
- * we can't spill a page in a child txn if it was already spilled in a
- * parent txn. That would alter the parent txns' data even though
- * the child hasn't committed yet, and we'd have no way to undo it if
- * the child aborted. */
-static int mdbx_txn_spill(MDBX_txn *txn, MDBX_cursor *m0, unsigned need) {
-#ifndef MDBX_DEBUG_SPILLING
-  if (likely(txn->tw.dirtyroom > need))
-    return MDBX_SUCCESS;
-  unsigned spill = need - txn->tw.dirtyroom;
-#else
-  /* spill at least one page if defined MDBX_DEBUG_SPILLING */
-  unsigned spill = (need > txn->tw.dirtyroom) ? need - txn->tw.dirtyroom : 1;
-#endif /* MDBX_DEBUG_SPILLING */
-
-  const unsigned dirty = txn->tw.dirtylist->length;
-  const unsigned spill_min =
-      txn->mt_env->me_options.spill_min_denominator
-          ? dirty / txn->mt_env->me_options.spill_min_denominator
-          : 0;
-  const unsigned spill_max =
-      dirty - (txn->mt_env->me_options.spill_max_denominator
-                   ? dirty / txn->mt_env->me_options.spill_max_denominator
-                   : 0);
-  spill = (spill > spill_min) ? spill : spill_min;
-  spill = (spill < spill_max) ? spill : spill_max;
-  if (!spill)
-    return MDBX_SUCCESS;
-
-  mdbx_notice("spilling %u dirty-entries (have %u dirty-room, need %u)", spill,
-              txn->tw.dirtyroom, need);
-  mdbx_tassert(txn, txn->tw.dirtylist->length >= spill);
-
-  int rc;
-  if (!txn->tw.spill_pages) {
-    txn->tw.spill_least_removed = INT_MAX;
-    txn->tw.spill_pages = mdbx_pnl_alloc(spill);
-    if (unlikely(!txn->tw.spill_pages)) {
-      rc = MDBX_ENOMEM;
-      goto bailout;
-    }
-  } else {
-    /* purge deleted slots */
-    mdbx_spill_purge(txn);
-    rc = mdbx_pnl_reserve(&txn->tw.spill_pages, spill);
-    (void)rc /* ignore since the resulting list may be shorter
-     and mdbx_pnl_append() will increase pnl on demand */
-        ;
-  }
-
-  /* Preserve pages which may soon be dirtied again */
-  mdbx_txn_xkeep(txn, m0, P_DIRTY, true);
-
-  MDBX_dpl *const dl = mdbx_dpl_sort(txn->tw.dirtylist);
-  /* Save the page IDs of all the pages we're flushing */
-  /* flush from the tail forward, this saves a lot of shifting later on. */
-  const unsigned dl_len_before = dl->length;
-  unsigned spilled = 0;
-  unsigned keep = dl_len_before;
-  for (; keep && spill; keep--) {
-    const pgno_t pgno = dl->items[keep].pgno;
-    MDBX_page *dp = dl->items[keep].ptr;
-    const unsigned npages = IS_OVERFLOW(dp) ? dp->mp_pages : 1;
-    if (dp->mp_flags & (P_LOOSE | P_KEEP)) {
-      mdbx_debug("skip %s %u page %" PRIaPGNO,
-                 (dp->mp_flags & P_LOOSE) ? "loose" : "keep", npages,
-                 dp->mp_pgno);
-    skip:
-      continue;
-    }
-    /* Can't spill twice,
-     * make sure it's not already in a parent's spill list(s). */
-    MDBX_txn *parent = txn->mt_parent;
-    if (parent && (parent->mt_flags & MDBX_TXN_SPILLS)) {
-      do
-        if (parent->tw.spill_pages &&
-            mdbx_pnl_intersect(parent->tw.spill_pages, pgno << 1,
-                               npages << 1)) {
-          mdbx_debug("skip parent-spilled %u page %" PRIaPGNO, npages, pgno);
-          dp->mp_flags |= P_KEEP;
-          goto skip;
-        }
-      while ((parent = parent->mt_parent) != nullptr);
-    }
-    mdbx_debug("spill %u page %" PRIaPGNO, npages, dp->mp_pgno);
-    rc = mdbx_pnl_append_range(true, &txn->tw.spill_pages, pgno << 1, npages);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto bailout;
-    spill--;
-    spilled += 1;
-  }
-  mdbx_pnl_sort(txn->tw.spill_pages);
-
-  /* Flush the spilled part of dirty list */
-  rc = mdbx_page_flush(txn, keep);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto bailout;
-
-  /* Reset any dirty pages we kept that page_flush didn't see */
-  mdbx_tassert(txn, dl_len_before - spilled == dl->length);
-  mdbx_txn_xkeep(txn, m0, P_DIRTY | P_KEEP, keep > 0);
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-
-bailout:
-  txn->mt_flags |= rc ? MDBX_TXN_ERROR : MDBX_TXN_SPILLS;
-  return rc;
-}
-
-static int mdbx_cursor_spill(MDBX_cursor *mc, const MDBX_val *key,
-                             const MDBX_val *data) {
-  if (mc->mc_flags & C_SUB)
-    return MDBX_SUCCESS;
-  MDBX_txn *txn = mc->mc_txn;
-  if (txn->mt_flags & MDBX_WRITEMAP)
-    return MDBX_SUCCESS;
-
-  /* Estimate how much space this operation will take: */
-  /* 1) Max b-tree height, reasonable enough with including dups' sub-tree */
-  unsigned need = CURSOR_STACK + 3;
-  /* 2) GC/FreeDB for any payload */
-  if (mc->mc_dbi > FREE_DBI) {
-    need += txn->mt_dbs[FREE_DBI].md_depth + 3;
-    /* 3) Named DBs also dirty the main DB */
-    if (mc->mc_dbi > MAIN_DBI)
-      need += txn->mt_dbs[MAIN_DBI].md_depth + 3;
-  }
-  /* 4) Factor the key+data which to be put in */
-  need += bytes2pgno(txn->mt_env, node_size(key, data)) + 1;
-  return mdbx_txn_spill(txn, mc, need);
-}
-
-/*----------------------------------------------------------------------------*/
-
-static __always_inline bool meta_bootid_match(const MDBX_meta *meta) {
-  return memcmp(&meta->mm_bootid, &bootid, 16) == 0 &&
-         (bootid.x | bootid.y) != 0;
-}
-
-static bool meta_weak_acceptable(const MDBX_env *env, const MDBX_meta *meta,
-                                 const int lck_exclusive) {
-  return lck_exclusive ? /* exclusive lock */ meta_bootid_match(meta)
-                       : /* db already opened */ env->me_lck &&
-                             (env->me_lck->mti_envmode.weak & MDBX_RDONLY) == 0;
-}
-
-#define METAPAGE(env, n) page_meta(pgno2page(env, n))
-#define METAPAGE_END(env) METAPAGE(env, NUM_METAS)
-
-static __inline txnid_t meta_txnid(const MDBX_env *env, const MDBX_meta *meta,
-                                   const bool allow_volatile) {
-  mdbx_memory_fence(mo_AcquireRelease, false);
-  txnid_t a = unaligned_peek_u64(4, &meta->mm_txnid_a);
-  txnid_t b = unaligned_peek_u64(4, &meta->mm_txnid_b);
-  if (allow_volatile)
-    return (a == b) ? a : 0;
-  mdbx_assert(env, a == b);
-  return a;
-}
-
-static __inline txnid_t mdbx_meta_txnid_stable(const MDBX_env *env,
-                                               const MDBX_meta *meta) {
-  return meta_txnid(env, meta, false);
-}
-
-static __inline txnid_t mdbx_meta_txnid_fluid(const MDBX_env *env,
-                                              const MDBX_meta *meta) {
-  return meta_txnid(env, meta, true);
-}
-
-static __inline void mdbx_meta_update_begin(const MDBX_env *env,
-                                            MDBX_meta *meta, txnid_t txnid) {
-  mdbx_assert(env, meta >= METAPAGE(env, 0) && meta < METAPAGE_END(env));
-  mdbx_assert(env, unaligned_peek_u64(4, meta->mm_txnid_a) < txnid &&
-                       unaligned_peek_u64(4, meta->mm_txnid_b) < txnid);
-  (void)env;
-  unaligned_poke_u64(4, meta->mm_txnid_b, 0);
-  mdbx_memory_fence(mo_AcquireRelease, true);
-  unaligned_poke_u64(4, meta->mm_txnid_a, txnid);
-}
-
-static __inline void mdbx_meta_update_end(const MDBX_env *env, MDBX_meta *meta,
-                                          txnid_t txnid) {
-  mdbx_assert(env, meta >= METAPAGE(env, 0) && meta < METAPAGE_END(env));
-  mdbx_assert(env, unaligned_peek_u64(4, meta->mm_txnid_a) == txnid);
-  mdbx_assert(env, unaligned_peek_u64(4, meta->mm_txnid_b) < txnid);
-  (void)env;
-  mdbx_jitter4testing(true);
-  memcpy(&meta->mm_bootid, &bootid, 16);
-  unaligned_poke_u64(4, meta->mm_txnid_b, txnid);
-  mdbx_memory_fence(mo_AcquireRelease, true);
-}
-
-static __inline void mdbx_meta_set_txnid(const MDBX_env *env, MDBX_meta *meta,
-                                         txnid_t txnid) {
-  mdbx_assert(env, !env->me_map || meta < METAPAGE(env, 0) ||
-                       meta >= METAPAGE_END(env));
-  (void)env;
-  /* update inconsistent since this function used ONLY for filling meta-image
-   * for writing, but not the actual meta-page */
-  memcpy(&meta->mm_bootid, &bootid, 16);
-  unaligned_poke_u64(4, meta->mm_txnid_a, txnid);
-  unaligned_poke_u64(4, meta->mm_txnid_b, txnid);
-}
-
-static __inline uint64_t mdbx_meta_sign(const MDBX_meta *meta) {
-  uint64_t sign = MDBX_DATASIGN_NONE;
-#if 0 /* TODO */
-  sign = hippeus_hash64(...);
-#else
-  (void)meta;
-#endif
-  /* LY: newer returns MDBX_DATASIGN_NONE or MDBX_DATASIGN_WEAK */
-  return (sign > MDBX_DATASIGN_WEAK) ? sign : ~sign;
-}
-
-enum meta_choise_mode { prefer_last, prefer_steady };
-
-static __inline bool mdbx_meta_ot(const enum meta_choise_mode mode,
-                                  const MDBX_env *env, const MDBX_meta *a,
-                                  const MDBX_meta *b) {
-  mdbx_jitter4testing(true);
-  txnid_t txnid_a = mdbx_meta_txnid_fluid(env, a);
-  txnid_t txnid_b = mdbx_meta_txnid_fluid(env, b);
-
-  mdbx_jitter4testing(true);
-  switch (mode) {
-  default:
-    assert(false);
-    __unreachable();
-    /* fall through */
-    __fallthrough;
-  case prefer_steady:
-    if (META_IS_STEADY(a) != META_IS_STEADY(b))
-      return META_IS_STEADY(b);
-    /* fall through */
-    __fallthrough;
-  case prefer_last:
-    mdbx_jitter4testing(true);
-    if (txnid_a == txnid_b)
-      return META_IS_STEADY(b);
-    return txnid_a < txnid_b;
-  }
-}
-
-static __inline bool mdbx_meta_eq(const MDBX_env *env, const MDBX_meta *a,
-                                  const MDBX_meta *b) {
-  mdbx_jitter4testing(true);
-  const txnid_t txnid = mdbx_meta_txnid_fluid(env, a);
-  if (!txnid || txnid != mdbx_meta_txnid_fluid(env, b))
-    return false;
-
-  mdbx_jitter4testing(true);
-  if (META_IS_STEADY(a) != META_IS_STEADY(b))
-    return false;
-
-  mdbx_jitter4testing(true);
-  return true;
-}
-
-static int mdbx_meta_eq_mask(const MDBX_env *env) {
-  MDBX_meta *m0 = METAPAGE(env, 0);
-  MDBX_meta *m1 = METAPAGE(env, 1);
-  MDBX_meta *m2 = METAPAGE(env, 2);
-
-  int rc = mdbx_meta_eq(env, m0, m1) ? 1 : 0;
-  if (mdbx_meta_eq(env, m1, m2))
-    rc += 2;
-  if (mdbx_meta_eq(env, m2, m0))
-    rc += 4;
-  return rc;
-}
-
-static __inline MDBX_meta *mdbx_meta_recent(const enum meta_choise_mode mode,
-                                            const MDBX_env *env, MDBX_meta *a,
-                                            MDBX_meta *b) {
-  const bool a_older_that_b = mdbx_meta_ot(mode, env, a, b);
-  mdbx_assert(env, !mdbx_meta_eq(env, a, b));
-  return a_older_that_b ? b : a;
-}
-
-static __inline MDBX_meta *mdbx_meta_ancient(const enum meta_choise_mode mode,
-                                             const MDBX_env *env, MDBX_meta *a,
-                                             MDBX_meta *b) {
-  const bool a_older_that_b = mdbx_meta_ot(mode, env, a, b);
-  mdbx_assert(env, !mdbx_meta_eq(env, a, b));
-  return a_older_that_b ? a : b;
-}
-
-static __inline MDBX_meta *
-mdbx_meta_mostrecent(const enum meta_choise_mode mode, const MDBX_env *env) {
-  MDBX_meta *m0 = METAPAGE(env, 0);
-  MDBX_meta *m1 = METAPAGE(env, 1);
-  MDBX_meta *m2 = METAPAGE(env, 2);
-
-  MDBX_meta *head = mdbx_meta_recent(mode, env, m0, m1);
-  head = mdbx_meta_recent(mode, env, head, m2);
-  return head;
-}
-
-static MDBX_meta *mdbx_meta_steady(const MDBX_env *env) {
-  return mdbx_meta_mostrecent(prefer_steady, env);
-}
-
-static MDBX_meta *mdbx_meta_head(const MDBX_env *env) {
-  return mdbx_meta_mostrecent(prefer_last, env);
-}
-
-static txnid_t mdbx_recent_committed_txnid(const MDBX_env *env) {
-  while (true) {
-    const MDBX_meta *head = mdbx_meta_head(env);
-    const txnid_t recent = mdbx_meta_txnid_fluid(env, head);
-    mdbx_compiler_barrier();
-    if (likely(head == mdbx_meta_head(env) &&
-               recent == mdbx_meta_txnid_fluid(env, head)))
-      return recent;
-  }
-}
-
-static txnid_t mdbx_recent_steady_txnid(const MDBX_env *env) {
-  while (true) {
-    const MDBX_meta *head = mdbx_meta_steady(env);
-    const txnid_t recent = mdbx_meta_txnid_fluid(env, head);
-    mdbx_compiler_barrier();
-    if (likely(head == mdbx_meta_steady(env) &&
-               recent == mdbx_meta_txnid_fluid(env, head)))
-      return recent;
-  }
-}
-
-static const char *mdbx_durable_str(const MDBX_meta *const meta) {
-  if (META_IS_STEADY(meta))
-    return (unaligned_peek_u64(4, meta->mm_datasync_sign) ==
-            mdbx_meta_sign(meta))
-               ? "Steady"
-               : "Tainted";
-  return "Weak";
-}
-
-/*----------------------------------------------------------------------------*/
-
-/* Find oldest txnid still referenced. */
-static txnid_t mdbx_find_oldest(const MDBX_txn *txn) {
-  mdbx_tassert(txn, (txn->mt_flags & MDBX_TXN_RDONLY) == 0);
-  MDBX_env *env = txn->mt_env;
-  const txnid_t edge = mdbx_recent_steady_txnid(env);
-  mdbx_tassert(txn, edge <= txn->mt_txnid);
-
-  MDBX_lockinfo *const lck = env->me_lck;
-  if (unlikely(lck == NULL /* exclusive mode */))
-    return atomic_store64(&env->me_lckless_stub.oldest, edge,
-                          mo_AcquireRelease);
-
-  const txnid_t last_oldest =
-      atomic_load64(&lck->mti_oldest_reader, mo_AcquireRelease);
-  mdbx_tassert(txn, edge >= last_oldest);
-  if (likely(last_oldest == edge))
-    return edge;
-
-  const uint32_t nothing_changed = MDBX_STRING_TETRAD("None");
-  const uint32_t snap_readers_refresh_flag =
-      atomic_load32(&lck->mti_readers_refresh_flag, mo_AcquireRelease);
-  mdbx_jitter4testing(false);
-  if (snap_readers_refresh_flag == nothing_changed)
-    return last_oldest;
-
-  txnid_t oldest = edge;
-  atomic_store32(&lck->mti_readers_refresh_flag, nothing_changed,
-                 mo_AcquireRelease);
-  const unsigned snap_nreaders =
-      atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-  for (unsigned i = 0; i < snap_nreaders; ++i) {
-    if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease)) {
-      /* mdbx_jitter4testing(true); */
-      const txnid_t snap = safe64_read(&lck->mti_readers[i].mr_txnid);
-      if (oldest > snap && last_oldest <= /* ignore pending updates */ snap) {
-        oldest = snap;
-        if (oldest == last_oldest)
-          return oldest;
-      }
-    }
-  }
-
-  if (oldest != last_oldest) {
-    mdbx_notice("update oldest %" PRIaTXN " -> %" PRIaTXN, last_oldest, oldest);
-    mdbx_tassert(txn, oldest >= lck->mti_oldest_reader.weak);
-    atomic_store64(&lck->mti_oldest_reader, oldest, mo_AcquireRelease);
-  }
-  return oldest;
-}
-
-/* Find largest mvcc-snapshot still referenced. */
-static __cold pgno_t mdbx_find_largest(MDBX_env *env, pgno_t largest) {
-  MDBX_lockinfo *const lck = env->me_lck;
-  if (likely(lck != NULL /* exclusive mode */)) {
-    const unsigned snap_nreaders =
-        atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-    for (unsigned i = 0; i < snap_nreaders; ++i) {
-    retry:
-      if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease)) {
-        /* mdbx_jitter4testing(true); */
-        const pgno_t snap_pages = atomic_load32(
-            &lck->mti_readers[i].mr_snapshot_pages_used, mo_Relaxed);
-        const txnid_t snap_txnid = safe64_read(&lck->mti_readers[i].mr_txnid);
-        if (unlikely(
-                snap_pages !=
-                    atomic_load32(&lck->mti_readers[i].mr_snapshot_pages_used,
-                                  mo_AcquireRelease) ||
-                snap_txnid != safe64_read(&lck->mti_readers[i].mr_txnid)))
-          goto retry;
-        if (largest < snap_pages &&
-            atomic_load64(&lck->mti_oldest_reader, mo_AcquireRelease) <=
-                /* ignore pending updates */ snap_txnid &&
-            snap_txnid <= env->me_txn0->mt_txnid)
-          largest = snap_pages;
-      }
-    }
-  }
-
-  return largest;
-}
-
-/* Add a page to the txn's dirty list */
-static int __must_check_result mdbx_page_dirty(MDBX_txn *txn, MDBX_page *mp) {
-  mp->mp_txnid = INVALID_TXNID;
-  mp->mp_flags |= P_DIRTY;
-  if (unlikely(txn->tw.dirtyroom == 0)) {
-    mdbx_error("Dirtyroom is depleted, DPL length %u",
-               txn->tw.dirtylist->length);
-    return MDBX_TXN_FULL;
-  }
-  const int rc = mdbx_dpl_append(txn, mp->mp_pgno, mp);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    txn->mt_flags |= MDBX_TXN_ERROR;
-    return rc;
-  }
-  txn->tw.dirtyroom--;
-  assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-  mdbx_tassert(txn, txn->mt_parent ||
-                        txn->tw.dirtyroom + txn->tw.dirtylist->length ==
-                            txn->mt_env->me_options.dp_limit);
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  return MDBX_SUCCESS;
-}
-
-#if !(defined(_WIN32) || defined(_WIN64))
-static __always_inline __maybe_unused int ignore_enosys(int err) {
-#ifdef ENOSYS
-  if (err == ENOSYS)
-    return MDBX_RESULT_TRUE;
-#endif /* ENOSYS */
-#ifdef ENOIMPL
-  if (err == ENOIMPL)
-    return MDBX_RESULT_TRUE;
-#endif /* ENOIMPL */
-#ifdef ENOTSUP
-  if (err == ENOTSUP)
-    return MDBX_RESULT_TRUE;
-#endif /* ENOTSUP */
-#ifdef ENOSUPP
-  if (err == ENOSUPP)
-    return MDBX_RESULT_TRUE;
-#endif /* ENOSUPP */
-#ifdef EOPNOTSUPP
-  if (err == EOPNOTSUPP)
-    return MDBX_RESULT_TRUE;
-#endif /* EOPNOTSUPP */
-  if (err == EAGAIN)
-    return MDBX_RESULT_TRUE;
-  return err;
-}
-#endif /* defined(_WIN32) || defined(_WIN64) */
-
-/* Turn on/off readahead. It's harmful when the DB is larger than RAM. */
-static __cold int mdbx_set_readahead(MDBX_env *env, const size_t offset,
-                                     const size_t length, const bool enable) {
-  assert(length > 0);
-  mdbx_notice("readahead %s %u..%u", enable ? "ON" : "OFF",
-              bytes2pgno(env, offset), bytes2pgno(env, offset + length));
-
-#if defined(F_RDAHEAD)
-  if (unlikely(fcntl(env->me_lazy_fd, F_RDAHEAD, enable) == -1))
-    return errno;
-#endif /* F_RDAHEAD */
-
-  if (enable) {
-#if defined(F_RDADVISE)
-    struct radvisory hint;
-    hint.ra_offset = offset;
-    hint.ra_count = length;
-    (void)/* Ignore ENOTTY for DB on the ram-disk and so on */ fcntl(
-        env->me_lazy_fd, F_RDADVISE, &hint);
-#endif /* F_RDADVISE */
-#if defined(MADV_WILLNEED)
-    int err = madvise(env->me_map + offset, length, MADV_WILLNEED)
-                  ? ignore_enosys(errno)
-                  : MDBX_SUCCESS;
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#elif defined(POSIX_MADV_WILLNEED)
-    int err = ignore_enosys(
-        posix_madvise(env->me_map + offset, length, POSIX_MADV_WILLNEED));
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#elif defined(_WIN32) || defined(_WIN64)
-    if (mdbx_PrefetchVirtualMemory) {
-      WIN32_MEMORY_RANGE_ENTRY hint;
-      hint.VirtualAddress = env->me_map + offset;
-      hint.NumberOfBytes = length;
-      (void)mdbx_PrefetchVirtualMemory(GetCurrentProcess(), 1, &hint, 0);
-    }
-#elif defined(POSIX_FADV_WILLNEED)
-    int err = ignore_enosys(
-        posix_fadvise(env->me_lazy_fd, offset, length, POSIX_FADV_WILLNEED));
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#endif /* MADV_WILLNEED */
-  } else {
-#if defined(MADV_RANDOM)
-    int err = madvise(env->me_map + offset, length, MADV_RANDOM)
-                  ? ignore_enosys(errno)
-                  : MDBX_SUCCESS;
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#elif defined(POSIX_MADV_RANDOM)
-    int err = ignore_enosys(
-        posix_madvise(env->me_map + offset, length, POSIX_MADV_RANDOM));
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#elif defined(POSIX_FADV_RANDOM)
-    int err = ignore_enosys(
-        posix_fadvise(env->me_lazy_fd, offset, length, POSIX_FADV_RANDOM));
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#endif /* MADV_RANDOM */
-  }
-  return MDBX_SUCCESS;
-}
-
-static __cold int mdbx_mapresize(MDBX_env *env, const pgno_t used_pgno,
-                                 const pgno_t size_pgno,
-                                 const pgno_t limit_pgno, const bool implicit) {
-  if ((env->me_flags & MDBX_WRITEMAP) && env->me_unsynced_pages->weak) {
-    int err = mdbx_msync(&env->me_dxb_mmap, 0,
-                         pgno_align2os_bytes(env, used_pgno), true);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-  }
-
-  const size_t limit_bytes = pgno_align2os_bytes(env, limit_pgno);
-  const size_t size_bytes = pgno_align2os_bytes(env, size_pgno);
-  const size_t prev_size = env->me_dxb_mmap.current;
-  const size_t prev_limit = env->me_dxb_mmap.limit;
-  const void *const prev_addr = env->me_map;
-
-  mdbx_verbose("resize datafile/mapping: "
-               "present %" PRIuPTR " -> %" PRIuPTR ", "
-               "limit %" PRIuPTR " -> %" PRIuPTR,
-               prev_size, size_bytes, prev_limit, limit_bytes);
-
-  mdbx_assert(env, limit_bytes >= size_bytes);
-  mdbx_assert(env, bytes2pgno(env, size_bytes) >= size_pgno);
-  mdbx_assert(env, bytes2pgno(env, limit_bytes) >= limit_pgno);
-
-#if defined(_WIN32) || defined(_WIN64)
-  /* Acquire guard in exclusive mode for:
-   *   - to avoid collision between read and write txns around env->me_dbgeo;
-   *   - to avoid attachment of new reading threads (see mdbx_rdt_lock); */
-  mdbx_srwlock_AcquireExclusive(&env->me_remap_guard);
-  mdbx_handle_array_t *suspended = NULL;
-  mdbx_handle_array_t array_onstack;
-  int rc = MDBX_SUCCESS;
-  if (limit_bytes == env->me_dxb_mmap.limit &&
-      size_bytes == env->me_dxb_mmap.current &&
-      size_bytes == env->me_dxb_mmap.filesize)
-    goto bailout;
-
-  /* 1) Windows allows only extending a read-write section, but not a
-   *    corresponding mapped view. Therefore in other cases we must suspend
-   *    the local threads for safe remap.
-   * 2) At least on Windows 10 1803 the entire mapped section is unavailable
-   *    for short time during NtExtendSection() or VirtualAlloc() execution.
-   * 3) Under Wine runtime environment on Linux a section extending is not
-   *    supported. Therefore thread suspending is always required.
-   *
-   * THEREFORE LOCAL THREADS SUSPENDING IS ALWAYS REQUIRED! */
-  array_onstack.limit = ARRAY_LENGTH(array_onstack.handles);
-  array_onstack.count = 0;
-  suspended = &array_onstack;
-  rc = mdbx_suspend_threads_before_remap(env, &suspended);
-  if (rc != MDBX_SUCCESS) {
-    mdbx_error("failed suspend-for-remap: errcode %d", rc);
-    goto bailout;
-  }
-  const bool mapping_can_be_moved = !implicit;
-#else /* Windows */
-  /* Acquire guard to avoid collision between read and write txns
-   * around env->me_dbgeo */
-  bool mapping_can_be_moved = false;
-  int rc = mdbx_fastmutex_acquire(&env->me_remap_guard);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  if (limit_bytes == env->me_dxb_mmap.limit &&
-      size_bytes == env->me_dxb_mmap.current)
-    goto bailout;
-
-  if (limit_bytes != env->me_dxb_mmap.limit && env->me_lck && !implicit) {
-    int err = mdbx_rdt_lock(env) /* lock readers table until remap done */;
-    if (unlikely(MDBX_IS_ERROR(err))) {
-      rc = err;
-      goto bailout;
-    }
-
-    /* looking for readers from this process */
-    MDBX_lockinfo *const lck = env->me_lck;
-    const unsigned snap_nreaders =
-        atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-    mapping_can_be_moved = true;
-    for (unsigned i = 0; i < snap_nreaders; ++i) {
-      if (lck->mti_readers[i].mr_pid.weak == env->me_pid &&
-          lck->mti_readers[i].mr_tid.weak != mdbx_thread_self()) {
-        /* the base address of the mapping can't be changed since
-         * the other reader thread from this process exists. */
-        mdbx_rdt_unlock(env);
-        mapping_can_be_moved = false;
-        break;
-      }
-    }
-  }
-
-#endif /* ! Windows */
-
-  if (size_bytes < prev_size) {
-    mdbx_notice("resize-MADV_%s %u..%u",
-                (env->me_flags & MDBX_WRITEMAP) ? "REMOVE" : "DONTNEED",
-                size_pgno, bytes2pgno(env, prev_size));
-    rc = MDBX_RESULT_TRUE;
-#if defined(MADV_REMOVE)
-    if (env->me_flags & MDBX_WRITEMAP)
-      rc =
-          madvise(env->me_map + size_bytes, prev_size - size_bytes, MADV_REMOVE)
-              ? ignore_enosys(errno)
-              : MDBX_SUCCESS;
-#endif /* MADV_REMOVE */
-#if defined(MADV_DONTNEED)
-    if (rc == MDBX_RESULT_TRUE)
-      rc = madvise(env->me_map + size_bytes, prev_size - size_bytes,
-                   MADV_DONTNEED)
-               ? ignore_enosys(errno)
-               : MDBX_SUCCESS;
-#elif defined(POSIX_MADV_DONTNEED)
-    if (rc == MDBX_RESULT_TRUE)
-      rc = ignore_enosys(posix_madvise(env->me_map + size_bytes,
-                                       prev_size - size_bytes,
-                                       POSIX_MADV_DONTNEED));
-#elif defined(POSIX_FADV_DONTNEED)
-    if (rc == MDBX_RESULT_TRUE)
-      rc = ignore_enosys(posix_fadvise(env->me_lazy_fd, size_bytes,
-                                       prev_size - size_bytes,
-                                       POSIX_FADV_DONTNEED));
-#endif /* MADV_DONTNEED */
-    if (unlikely(MDBX_IS_ERROR(rc)))
-      goto bailout;
-    if (env->me_discarded_tail->weak > size_pgno)
-      env->me_discarded_tail->weak = size_pgno;
-  }
-
-  rc = mdbx_mresize(env->me_flags, &env->me_dxb_mmap, size_bytes, limit_bytes,
-                    mapping_can_be_moved);
-  if (rc == MDBX_SUCCESS && (env->me_flags & MDBX_NORDAHEAD) == 0) {
-    const int readahead =
-        mdbx_is_readahead_reasonable(size_bytes, -(intptr_t)prev_size);
-    if (readahead == MDBX_RESULT_FALSE)
-      rc = mdbx_set_readahead(
-          env, 0, (size_bytes > prev_size) ? size_bytes : prev_size, false);
-    else if (readahead == MDBX_RESULT_TRUE) {
-      const size_t readahead_pivot =
-          (limit_bytes != prev_limit || env->me_dxb_mmap.address != prev_addr
-#if defined(_WIN32) || defined(_WIN64)
-           || prev_size > size_bytes
-#endif /* Windows */
-           )
-              ? 0 /* reassign readahead to the entire map
-                     because it was remapped */
-              : prev_size;
-      if (size_bytes > readahead_pivot) {
-        env->me_discarded_tail->weak = size_pgno;
-        rc = mdbx_set_readahead(env, readahead_pivot,
-                                size_bytes - readahead_pivot, true);
-      }
-    }
-  }
-
-bailout:
-  if (rc == MDBX_SUCCESS) {
-#if defined(_WIN32) || defined(_WIN64)
-    mdbx_assert(env, size_bytes == env->me_dxb_mmap.current);
-    mdbx_assert(env, size_bytes <= env->me_dxb_mmap.filesize);
-    mdbx_assert(env, limit_bytes == env->me_dxb_mmap.limit);
-#endif /* Windows */
-#ifdef MDBX_USE_VALGRIND
-    if (prev_limit != env->me_dxb_mmap.limit || prev_addr != env->me_map) {
-      VALGRIND_DISCARD(env->me_valgrind_handle);
-      env->me_valgrind_handle = 0;
-      if (env->me_dxb_mmap.limit)
-        env->me_valgrind_handle =
-            VALGRIND_CREATE_BLOCK(env->me_map, env->me_dxb_mmap.limit, "mdbx");
-    }
-#endif /* MDBX_USE_VALGRIND */
-  } else {
-    if (rc != MDBX_UNABLE_EXTEND_MAPSIZE) {
-      mdbx_error("failed resize datafile/mapping: "
-                 "present %" PRIuPTR " -> %" PRIuPTR ", "
-                 "limit %" PRIuPTR " -> %" PRIuPTR ", errcode %d",
-                 prev_size, size_bytes, prev_limit, limit_bytes, rc);
-    } else {
-      mdbx_warning("unable resize datafile/mapping: "
-                   "present %" PRIuPTR " -> %" PRIuPTR ", "
-                   "limit %" PRIuPTR " -> %" PRIuPTR ", errcode %d",
-                   prev_size, size_bytes, prev_limit, limit_bytes, rc);
-    }
-    if (!env->me_dxb_mmap.address) {
-      env->me_flags |= MDBX_FATAL_ERROR;
-      if (env->me_txn)
-        env->me_txn->mt_flags |= MDBX_TXN_ERROR;
-      rc = MDBX_PANIC;
-    }
-  }
-
-#if defined(_WIN32) || defined(_WIN64)
-  int err = MDBX_SUCCESS;
-  mdbx_srwlock_ReleaseExclusive(&env->me_remap_guard);
-  if (suspended) {
-    err = mdbx_resume_threads_after_remap(suspended);
-    if (suspended != &array_onstack)
-      mdbx_free(suspended);
-  }
-#else
-  if (env->me_lck && mapping_can_be_moved)
-    mdbx_rdt_unlock(env);
-  int err = mdbx_fastmutex_release(&env->me_remap_guard);
-#endif /* Windows */
-  if (err != MDBX_SUCCESS) {
-    mdbx_fatal("failed resume-after-remap: errcode %d", err);
-    return MDBX_PANIC;
-  }
-  return rc;
-}
-
-static __cold int mdbx_mapresize_implicit(MDBX_env *env, const pgno_t used_pgno,
-                                          const pgno_t size_pgno,
-                                          const pgno_t limit_pgno) {
-  const pgno_t mapped_pgno = bytes2pgno(env, env->me_dxb_mmap.limit);
-  mdbx_assert(env, mapped_pgno >= used_pgno);
-  return mdbx_mapresize(
-      env, used_pgno, size_pgno,
-      (size_pgno > mapped_pgno)
-          ? limit_pgno
-          : /* The actual mapsize may be less since the geo.upper may be changed
-               by other process. So, avoids remapping until it necessary. */
-          mapped_pgno,
-      true);
-}
-
-static int mdbx_meta_unsteady(MDBX_env *env, const txnid_t last_steady,
-                              MDBX_meta *const meta) {
-  const uint64_t wipe = MDBX_DATASIGN_NONE;
-  if (unlikely(META_IS_STEADY(meta)) &&
-      mdbx_meta_txnid_stable(env, meta) <= last_steady) {
-    mdbx_warning("wipe txn #%" PRIaTXN ", meta %" PRIaPGNO, last_steady,
-                 data_page(meta)->mp_pgno);
-    if (env->me_flags & MDBX_WRITEMAP)
-      unaligned_poke_u64(4, meta->mm_datasync_sign, wipe);
-    else
-      return mdbx_pwrite(env->me_lazy_fd, &wipe, sizeof(meta->mm_datasync_sign),
-                         (uint8_t *)&meta->mm_datasync_sign - env->me_map);
-  }
-  return MDBX_SUCCESS;
-}
-
-__cold static int mdbx_wipe_steady(MDBX_env *env, const txnid_t last_steady) {
-  int err = mdbx_meta_unsteady(env, last_steady, METAPAGE(env, 0));
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-  err = mdbx_meta_unsteady(env, last_steady, METAPAGE(env, 1));
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-  err = mdbx_meta_unsteady(env, last_steady, METAPAGE(env, 2));
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-
-  if (env->me_flags & MDBX_WRITEMAP) {
-    mdbx_flush_incoherent_cpu_writeback();
-    err = mdbx_msync(&env->me_dxb_mmap, 0, pgno_align2os_bytes(env, NUM_METAS),
-                     false);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-  } else {
-#if MDBX_USE_SYNCFILERANGE
-    static bool syncfilerange_unavailable;
-    if (likely(!syncfilerange_unavailable)) {
-      if (likely(!sync_file_range(
-              env->me_lazy_fd, 0, pgno2bytes(env, NUM_METAS),
-              SYNC_FILE_RANGE_WRITE | SYNC_FILE_RANGE_WAIT_AFTER)))
-        goto done_filesync;
-      err = errno;
-      if (ignore_enosys(err) != MDBX_RESULT_TRUE)
-        return err;
-      syncfilerange_unavailable = true;
-    }
-#endif /* MDBX_USE_SYNCFILERANGE */
-    err = mdbx_fsync(env->me_lazy_fd, MDBX_SYNC_DATA);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-#if MDBX_USE_SYNCFILERANGE
-  done_filesync:
-#endif /* MDBX_USE_SYNCFILERANGE */
-    mdbx_flush_incoherent_mmap(env->me_map, pgno2bytes(env, NUM_METAS),
-                               env->me_os_psize);
-  }
-
-  if (likely(env->me_lck))
-    /* force oldest refresh */
-    atomic_store32(&env->me_lck->mti_readers_refresh_flag, true,
-                   mo_AcquireRelease);
-  return MDBX_SUCCESS;
-}
-
-static __inline txnid_t pp_txnid4chk(const MDBX_page *mp, const MDBX_txn *txn) {
-  return IS_DIRTY(mp)
-             ? txn->mt_txnid - 1
-             : (/* maybe zero in legacy DB */ mp->mp_txnid ? mp->mp_txnid
-                                                           : MIN_TXNID);
-}
-
-static __inline txnid_t pp_txnid2chk(const MDBX_txn *txn) {
-#ifdef MDBX_DEBUG_LEGACY
-  if (txn->mt_txnid < 2222)
-    return 0;
-#endif
-  return txn->mt_txnid;
-}
-
-/* Allocate page numbers and memory for writing.  Maintain mt_last_reclaimed,
- * mt_reclaimed_pglist and mt_next_pgno.  Set MDBX_TXN_ERROR on failure.
- *
- * If there are free pages available from older transactions, they
- * are re-used first. Otherwise allocate a new page at mt_next_pgno.
- * Do not modify the GC, just merge GC records into mt_reclaimed_pglist
- * and move mt_last_reclaimed to say which records were consumed.  Only this
- * function can create mt_reclaimed_pglist and move
- * mt_last_reclaimed/mt_next_pgno.
- *
- * [in] mc    cursor A cursor handle identifying the transaction and
- *            database for which we are allocating.
- * [in] num   the number of pages to allocate.
- * [out] mp   Address of the allocated page(s). Requests for multiple pages
- *            will always be satisfied by a single contiguous chunk of memory.
- *
- * Returns 0 on success, non-zero on failure.*/
-
-#define MDBX_ALLOC_CACHE 1
-#define MDBX_ALLOC_GC 2
-#define MDBX_ALLOC_NEW 4
-#define MDBX_ALLOC_ALL (MDBX_ALLOC_CACHE | MDBX_ALLOC_GC | MDBX_ALLOC_NEW)
-
-__hot static int mdbx_page_alloc(MDBX_cursor *mc, const unsigned num,
-                                 MDBX_page **const mp, int flags) {
-  int rc;
-  MDBX_txn *const txn = mc->mc_txn;
-  MDBX_env *const env = txn->mt_env;
-  MDBX_page *np;
-
-  const unsigned coalesce_threshold =
-      env->me_maxgc_ov1page - env->me_maxgc_ov1page / 4;
-  if (likely(flags & MDBX_ALLOC_GC)) {
-    flags |= env->me_flags & (MDBX_COALESCE | MDBX_LIFORECLAIM);
-    if (MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) > coalesce_threshold)
-      flags &= ~MDBX_COALESCE;
-    if (unlikely(
-            /* If mc is updating the GC, then the retired-list cannot play
-               catch-up with itself by growing while trying to save it. */
-            (mc->mc_flags & C_RECLAIMING) ||
-            /* avoid (recursive) search inside empty tree and while tree is
-               updating, https://github.com/erthink/libmdbx/issues/31 */
-            txn->mt_dbs[FREE_DBI].md_entries == 0 ||
-            /* If our dirty list is already full, we can't touch GC */
-            (txn->tw.dirtyroom < txn->mt_dbs[FREE_DBI].md_depth &&
-             !(txn->mt_dbistate[FREE_DBI] & DBI_DIRTY))))
-      flags &= ~(MDBX_ALLOC_GC | MDBX_COALESCE);
-  }
-
-  if (likely(num == 1 && (flags & MDBX_ALLOC_CACHE) != 0)) {
-    /* If there are any loose pages, just use them */
-    mdbx_assert(env, mp && num);
-    if (likely(txn->tw.loose_pages)) {
-#if MDBX_ENABLE_REFUND
-      if (txn->tw.loose_refund_wl > txn->mt_next_pgno) {
-        mdbx_refund(txn);
-        if (unlikely(!txn->tw.loose_pages))
-          goto no_loose;
-      }
-#endif /* MDBX_ENABLE_REFUND */
-
-      np = txn->tw.loose_pages;
-      txn->tw.loose_pages = np->mp_next;
-      txn->tw.loose_count--;
-      mdbx_debug("db %d use loose page %" PRIaPGNO, DDBI(mc), np->mp_pgno);
-      mdbx_tassert(txn, np->mp_pgno < txn->mt_next_pgno);
-      mdbx_ensure(env, np->mp_pgno >= NUM_METAS);
-      VALGRIND_MAKE_MEM_UNDEFINED(page_data(np), page_space(txn->mt_env));
-      ASAN_UNPOISON_MEMORY_REGION(page_data(np), page_space(txn->mt_env));
-      np->mp_flags = P_DIRTY;
-      np->mp_txnid = INVALID_TXNID;
-      *mp = np;
-      return MDBX_SUCCESS;
-    }
-  }
-#if MDBX_ENABLE_REFUND
-no_loose:
-#endif /* MDBX_ENABLE_REFUND */
-
-  mdbx_tassert(txn,
-               mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                     txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-  pgno_t pgno, *re_list = txn->tw.reclaimed_pglist;
-  unsigned range_begin = 0, re_len = MDBX_PNL_SIZE(re_list);
-  txnid_t oldest = 0, last = 0;
-  const unsigned wanna_range = num - 1;
-
-  while (true) { /* hsr-kick retry loop */
-    MDBX_cursor_couple recur;
-    for (MDBX_cursor_op op = MDBX_FIRST;;
-         op = (flags & MDBX_LIFORECLAIM) ? MDBX_PREV : MDBX_NEXT) {
-      MDBX_val key, data;
-
-      /* Seek a big enough contiguous page range.
-       * Prefer pages with lower pgno. */
-      mdbx_tassert(txn, mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                              txn->mt_next_pgno));
-      if ((flags & (MDBX_COALESCE | MDBX_ALLOC_CACHE)) == MDBX_ALLOC_CACHE &&
-          re_len > wanna_range) {
-        mdbx_tassert(txn, MDBX_PNL_LAST(re_list) < txn->mt_next_pgno &&
-                              MDBX_PNL_FIRST(re_list) < txn->mt_next_pgno);
-        range_begin = MDBX_PNL_ASCENDING ? 1 : re_len;
-        pgno = MDBX_PNL_LEAST(re_list);
-        if (likely(wanna_range == 0))
-          goto done;
-#if MDBX_PNL_ASCENDING
-        mdbx_tassert(txn, pgno == re_list[1] && range_begin == 1);
-        while (true) {
-          unsigned range_end = range_begin + wanna_range;
-          if (re_list[range_end] - pgno == wanna_range)
-            goto done;
-          if (range_end == re_len)
-            break;
-          pgno = re_list[++range_begin];
-        }
-#else
-        mdbx_tassert(txn, pgno == re_list[re_len] && range_begin == re_len);
-        while (true) {
-          if (re_list[range_begin - wanna_range] - pgno == wanna_range)
-            goto done;
-          if (range_begin == wanna_range)
-            break;
-          pgno = re_list[--range_begin];
-        }
-#endif /* MDBX_PNL sort-order */
-      }
-
-      if (op == MDBX_FIRST) { /* 1st iteration, setup cursor, etc */
-        if (unlikely(!(flags & MDBX_ALLOC_GC)))
-          break /* reclaiming is prohibited for now */;
-
-        /* Prepare to fetch more and coalesce */
-        oldest = (flags & MDBX_LIFORECLAIM)
-                     ? mdbx_find_oldest(txn)
-                     : atomic_load64(env->me_oldest, mo_AcquireRelease);
-        rc = mdbx_cursor_init(&recur.outer, txn, FREE_DBI);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto fail;
-        if (flags & MDBX_LIFORECLAIM) {
-          /* Begin from oldest reader if any */
-          if (oldest > MIN_TXNID) {
-            last = oldest - 1;
-            op = MDBX_SET_RANGE;
-          }
-        } else if (txn->tw.last_reclaimed) {
-          /* Continue lookup from txn->tw.last_reclaimed to oldest reader */
-          last = txn->tw.last_reclaimed;
-          op = MDBX_SET_RANGE;
-        }
-
-        key.iov_base = &last;
-        key.iov_len = sizeof(last);
-      }
-
-      if (!(flags & MDBX_LIFORECLAIM)) {
-        /* Do not try fetch more if the record will be too recent */
-        if (op != MDBX_FIRST && ++last >= oldest) {
-          oldest = mdbx_find_oldest(txn);
-          if (oldest <= last)
-            break;
-        }
-      }
-
-      rc = mdbx_cursor_get(&recur.outer, &key, NULL, op);
-      if (rc == MDBX_NOTFOUND && (flags & MDBX_LIFORECLAIM)) {
-        if (op == MDBX_SET_RANGE)
-          continue;
-        txnid_t snap = mdbx_find_oldest(txn);
-        if (oldest < snap) {
-          oldest = snap;
-          last = oldest - 1;
-          key.iov_base = &last;
-          key.iov_len = sizeof(last);
-          op = MDBX_SET_RANGE;
-          rc = mdbx_cursor_get(&recur.outer, &key, NULL, op);
-        }
-      }
-      if (unlikely(rc)) {
-        if (rc == MDBX_NOTFOUND)
-          break;
-        goto fail;
-      }
-
-      if (unlikely(key.iov_len != sizeof(txnid_t))) {
-        rc = MDBX_CORRUPTED;
-        goto fail;
-      }
-      last = unaligned_peek_u64(4, key.iov_base);
-      if (unlikely(last < MIN_TXNID || last > MAX_TXNID)) {
-        rc = MDBX_CORRUPTED;
-        goto fail;
-      }
-      if (oldest <= last) {
-        oldest = mdbx_find_oldest(txn);
-        if (oldest <= last) {
-          if (flags & MDBX_LIFORECLAIM)
-            continue;
-          break;
-        }
-      }
-
-      if (flags & MDBX_LIFORECLAIM) {
-        /* skip IDs of records that already reclaimed */
-        if (txn->tw.lifo_reclaimed) {
-          size_t i;
-          for (i = (size_t)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed); i > 0; --i)
-            if (txn->tw.lifo_reclaimed[i] == last)
-              break;
-          if (i)
-            continue;
-        }
-      }
-
-      /* Reading next GC record */
-      np = recur.outer.mc_pg[recur.outer.mc_top];
-      if (unlikely((rc = mdbx_node_read(
-                        &recur.outer,
-                        page_node(np, recur.outer.mc_ki[recur.outer.mc_top]),
-                        &data, pp_txnid4chk(np, txn))) != MDBX_SUCCESS))
-        goto fail;
-
-      if ((flags & MDBX_LIFORECLAIM) && !txn->tw.lifo_reclaimed) {
-        txn->tw.lifo_reclaimed = mdbx_txl_alloc();
-        if (unlikely(!txn->tw.lifo_reclaimed)) {
-          rc = MDBX_ENOMEM;
-          goto fail;
-        }
-      }
-
-      /* Append PNL from GC record to tw.reclaimed_pglist */
-      mdbx_cassert(mc, (mc->mc_flags & C_GCFREEZE) == 0);
-      pgno_t *gc_pnl = (pgno_t *)data.iov_base;
-      mdbx_tassert(txn, data.iov_len >= MDBX_PNL_SIZEOF(gc_pnl));
-      if (unlikely(data.iov_len < MDBX_PNL_SIZEOF(gc_pnl) ||
-                   !mdbx_pnl_check(gc_pnl, txn->mt_next_pgno))) {
-        rc = MDBX_CORRUPTED;
-        goto fail;
-      }
-      const unsigned gc_len = MDBX_PNL_SIZE(gc_pnl);
-      if (unlikely(/* resulting list is tool long */ gc_len +
-                       MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) >
-                   env->me_options.rp_augment_limit) &&
-          (((/* not a slot-request from gc-update */
-             mp || (flags & MDBX_LIFORECLAIM) == 0 ||
-             (txn->tw.lifo_reclaimed &&
-              MDBX_PNL_SIZE(txn->tw.lifo_reclaimed))) &&
-            /* have enough unallocated space */ pgno_add(
-                txn->mt_next_pgno, num) <= txn->mt_geo.upper) ||
-           gc_len + MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) >=
-               MDBX_PGL_LIMIT / 16 * 15)) {
-        /* Stop reclaiming to avoid overflow the page list.
-         * This is a rare case while search for a continuously multi-page region
-         * in a large database. https://github.com/erthink/libmdbx/issues/123 */
-        mdbx_debug("stop reclaiming to avoid PNL overflow: %u (current) + %u "
-                   "(chunk) -> %u",
-                   MDBX_PNL_SIZE(txn->tw.reclaimed_pglist), gc_len,
-                   gc_len + MDBX_PNL_SIZE(txn->tw.reclaimed_pglist));
-        flags &= ~(MDBX_ALLOC_GC | MDBX_COALESCE);
-        break;
-      }
-      rc = mdbx_pnl_need(&txn->tw.reclaimed_pglist, gc_len);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto fail;
-      re_list = txn->tw.reclaimed_pglist;
-
-      /* Remember ID of GC record */
-      if (flags & MDBX_LIFORECLAIM) {
-        rc = mdbx_txl_append(&txn->tw.lifo_reclaimed, last);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto fail;
-      }
-      txn->tw.last_reclaimed = last;
-
-      if (mdbx_log_enabled(MDBX_LOG_EXTRA)) {
-        mdbx_debug_extra("PNL read txn %" PRIaTXN " root %" PRIaPGNO
-                         " num %u, PNL",
-                         last, txn->mt_dbs[FREE_DBI].md_root, gc_len);
-        for (unsigned i = gc_len; i; i--)
-          mdbx_debug_extra_print(" %" PRIaPGNO, gc_pnl[i]);
-        mdbx_debug_extra_print("%s\n", ".");
-      }
-
-      /* Merge in descending sorted order */
-      const unsigned prev_re_len = MDBX_PNL_SIZE(re_list);
-      mdbx_pnl_xmerge(re_list, gc_pnl);
-      /* re-check to avoid duplicates */
-      if (unlikely(!mdbx_pnl_check(re_list, txn->mt_next_pgno))) {
-        rc = MDBX_CORRUPTED;
-        goto fail;
-      }
-      mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-
-      re_len = MDBX_PNL_SIZE(re_list);
-      mdbx_tassert(txn, re_len == 0 || re_list[re_len] < txn->mt_next_pgno);
-      if (MDBX_ENABLE_REFUND && re_len &&
-          unlikely(MDBX_PNL_MOST(re_list) == txn->mt_next_pgno - 1)) {
-        /* Refund suitable pages into "unallocated" space */
-        mdbx_refund(txn);
-        re_list = txn->tw.reclaimed_pglist;
-        re_len = MDBX_PNL_SIZE(re_list);
-      }
-
-      /* Done for a kick-reclaim mode, actually no page needed */
-      if (unlikely((flags & MDBX_ALLOC_CACHE) == 0))
-        return MDBX_SUCCESS;
-
-      /* Don't try to coalesce too much. */
-      if (re_len /* current size */ > coalesce_threshold ||
-          (re_len > prev_re_len && re_len - prev_re_len /* delta from prev */ >=
-                                       coalesce_threshold / 2))
-        flags &= ~MDBX_COALESCE;
-    }
-
-    if (F_ISSET(flags, MDBX_COALESCE | MDBX_ALLOC_CACHE)) {
-      flags -= MDBX_COALESCE;
-      continue;
-    }
-
-    /* There is no suitable pages in the GC and to be able to allocate
-     * we should CHOICE one of:
-     *  - make a new steady checkpoint if reclaiming was stopped by
-     *    the last steady-sync, or wipe it in the MDBX_UTTERLY_NOSYNC mode;
-     *  - kick lagging reader(s) if reclaiming was stopped by ones of it.
-     *  - extend the database file. */
-
-    /* Will use new pages from the map if nothing is suitable in the GC. */
-    range_begin = 0;
-    pgno = txn->mt_next_pgno;
-    const pgno_t next = pgno_add(pgno, num);
-
-    if (flags & MDBX_ALLOC_GC) {
-      const MDBX_meta *const head = mdbx_meta_head(env);
-      MDBX_meta *const steady = mdbx_meta_steady(env);
-      /* does reclaiming stopped at the last steady point? */
-      if (head != steady && META_IS_STEADY(steady) &&
-          oldest == mdbx_meta_txnid_stable(env, steady)) {
-        mdbx_debug("gc-kick-steady: head %" PRIaTXN "-%s, tail %" PRIaTXN
-                   "-%s, oldest %" PRIaTXN,
-                   mdbx_meta_txnid_stable(env, head), mdbx_durable_str(head),
-                   mdbx_meta_txnid_stable(env, steady),
-                   mdbx_durable_str(steady), oldest);
-        rc = MDBX_RESULT_TRUE;
-        const pgno_t autosync_threshold =
-            atomic_load32(env->me_autosync_threshold, mo_Relaxed);
-        const uint64_t autosync_period =
-            atomic_load64(env->me_autosync_period, mo_Relaxed);
-        /* wipe the last steady-point if one of:
-         *  - UTTERLY_NOSYNC mode AND auto-sync threshold is NOT specified
-         *  - UTTERLY_NOSYNC mode AND free space at steady-point is exhausted
-         * otherwise, make a new steady-point if one of:
-         *  - auto-sync threshold is specified and reached;
-         *  - upper limit of database size is reached;
-         *  - database is full (with the current file size)
-         *       AND auto-sync threshold it NOT specified */
-        if (F_ISSET(env->me_flags, MDBX_UTTERLY_NOSYNC) &&
-            ((autosync_threshold | autosync_period) == 0 ||
-             next >= steady->mm_geo.now)) {
-          /* wipe steady checkpoint in MDBX_UTTERLY_NOSYNC mode
-           * without any auto-sync threshold(s). */
-          rc = mdbx_wipe_steady(env, oldest);
-          mdbx_debug("gc-wipe-steady, rc %d", rc);
-          mdbx_assert(env, steady != mdbx_meta_steady(env));
-        } else if ((flags & MDBX_ALLOC_NEW) == 0 ||
-                   (autosync_threshold &&
-                    atomic_load32(env->me_unsynced_pages, mo_Relaxed) >=
-                        autosync_threshold) ||
-                   (autosync_period &&
-                    mdbx_osal_monotime() -
-                            atomic_load64(env->me_sync_timestamp, mo_Relaxed) >=
-                        autosync_period) ||
-                   next >= txn->mt_geo.upper ||
-                   (next >= txn->mt_end_pgno &&
-                    (autosync_threshold | autosync_period) == 0)) {
-          /* make steady checkpoint. */
-          MDBX_meta meta = *head;
-          rc = mdbx_sync_locked(env, env->me_flags & MDBX_WRITEMAP, &meta);
-          mdbx_debug("gc-make-steady, rc %d", rc);
-          mdbx_assert(env, steady != mdbx_meta_steady(env));
-        }
-        if (rc == MDBX_SUCCESS) {
-          if (mdbx_find_oldest(txn) > oldest)
-            continue;
-          /* it is reasonable check/kick lagging reader(s) here,
-           * since we made a new steady point or wipe the last. */
-          if (oldest < txn->mt_txnid - MDBX_TXNID_STEP &&
-              mdbx_kick_longlived_readers(env, oldest) > oldest)
-            continue;
-        } else if (unlikely(rc != MDBX_RESULT_TRUE))
-          goto fail;
-      }
-    }
-
-    /* don't kick lagging reader(s) if is enough unallocated space
-     * at the end of database file. */
-    if ((flags & MDBX_ALLOC_NEW) && next <= txn->mt_end_pgno)
-      goto done;
-    if ((flags & MDBX_ALLOC_GC) && oldest < txn->mt_txnid - MDBX_TXNID_STEP &&
-        mdbx_kick_longlived_readers(env, oldest) > oldest)
-      continue;
-
-    rc = MDBX_NOTFOUND;
-    if (flags & MDBX_ALLOC_NEW) {
-      rc = MDBX_MAP_FULL;
-      if (next <= txn->mt_geo.upper && txn->mt_geo.grow) {
-        mdbx_assert(env, next > txn->mt_end_pgno);
-        pgno_t aligned = pgno_align2os_pgno(
-            env, pgno_add(next, txn->mt_geo.grow - next % txn->mt_geo.grow));
-
-        if (aligned > txn->mt_geo.upper)
-          aligned = txn->mt_geo.upper;
-        mdbx_assert(env, aligned > txn->mt_end_pgno);
-
-        mdbx_verbose("try growth datafile to %" PRIaPGNO " pages (+%" PRIaPGNO
-                     ")",
-                     aligned, aligned - txn->mt_end_pgno);
-        rc = mdbx_mapresize_implicit(env, txn->mt_next_pgno, aligned,
-                                     txn->mt_geo.upper);
-        if (rc == MDBX_SUCCESS) {
-          env->me_txn->mt_end_pgno = aligned;
-          goto done;
-        }
-
-        mdbx_error("unable growth datafile to %" PRIaPGNO " pages (+%" PRIaPGNO
-                   "), errcode %d",
-                   aligned, aligned - txn->mt_end_pgno, rc);
-      } else {
-        mdbx_debug("gc-alloc: next %u > upper %u", next, txn->mt_geo.upper);
-      }
-    }
-
-  fail:
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-    if (likely(mp)) {
-      *mp = nullptr;
-      txn->mt_flags |= MDBX_TXN_ERROR;
-    }
-    mdbx_assert(env, rc != MDBX_SUCCESS);
-    return rc;
-  }
-
-done:
-  if (unlikely(mp == nullptr))
-    return MDBX_SUCCESS;
-  if (unlikely(txn->tw.dirtyroom < 1))
-    return MDBX_TXN_FULL;
-  mdbx_ensure(env, pgno >= NUM_METAS);
-  if (env->me_flags & MDBX_WRITEMAP) {
-    np = pgno2page(env, pgno);
-    /* LY: reset no-access flag from mdbx_page_loose() */
-    VALGRIND_MAKE_MEM_UNDEFINED(np, pgno2bytes(env, num));
-    ASAN_UNPOISON_MEMORY_REGION(np, pgno2bytes(env, num));
-  } else {
-    if (unlikely(!(np = mdbx_page_malloc(txn, num)))) {
-      rc = MDBX_ENOMEM;
-      goto fail;
-    }
-  }
-
-  if (range_begin) {
-    mdbx_cassert(mc, (mc->mc_flags & C_GCFREEZE) == 0);
-    mdbx_tassert(txn, pgno < txn->mt_next_pgno);
-    mdbx_tassert(txn, pgno == re_list[range_begin]);
-    /* Cutoff allocated pages from tw.reclaimed_pglist */
-#if MDBX_PNL_ASCENDING
-    for (unsigned i = range_begin + num; i <= re_len;)
-      re_list[range_begin++] = re_list[i++];
-    MDBX_PNL_SIZE(re_list) = re_len = range_begin - 1;
-#else
-    MDBX_PNL_SIZE(re_list) = re_len -= num;
-    for (unsigned i = range_begin - num; i < re_len;)
-      re_list[++i] = re_list[++range_begin];
-#endif
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-  } else {
-    txn->mt_next_pgno = pgno + num;
-    mdbx_assert(env, txn->mt_next_pgno <= txn->mt_end_pgno);
-  }
-
-  if (unlikely(env->me_flags & MDBX_PAGEPERTURB))
-    memset(np, -1, pgno2bytes(env, num));
-  VALGRIND_MAKE_MEM_UNDEFINED(np, pgno2bytes(env, num));
-
-  np->mp_pgno = pgno;
-  np->mp_leaf2_ksize = 0;
-  np->mp_flags = 0;
-  if ((mdbx_assert_enabled() || mdbx_audit_enabled()) && num > 1) {
-    np->mp_pages = num;
-    np->mp_flags = P_OVERFLOW;
-  }
-  rc = mdbx_page_dirty(txn, np);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto fail;
-  *mp = np;
-
-  mdbx_tassert(txn,
-               mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                     txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-  return MDBX_SUCCESS;
-}
-
-/* Copy the used portions of a non-overflow page. */
-__hot static void mdbx_page_copy(MDBX_page *dst, MDBX_page *src, size_t psize) {
-  STATIC_ASSERT(UINT16_MAX > MAX_PAGESIZE - PAGEHDRSZ);
-  STATIC_ASSERT(MIN_PAGESIZE > PAGEHDRSZ + NODESIZE * 4);
-  if (!IS_LEAF2(src)) {
-    size_t upper = src->mp_upper, lower = src->mp_lower, unused = upper - lower;
-
-    /* If page isn't full, just copy the used portion. Adjust
-     * alignment so memcpy may copy words instead of bytes. */
-    if (unused >= MDBX_CACHELINE_SIZE * 2) {
-      lower = ceil_powerof2(lower + PAGEHDRSZ, sizeof(void *));
-      upper = floor_powerof2(upper + PAGEHDRSZ, sizeof(void *));
-      memcpy(dst, src, lower);
-      dst = (void *)((char *)dst + upper);
-      src = (void *)((char *)src + upper);
-      psize -= upper;
-    }
-  }
-  memcpy(dst, src, psize);
-}
-
-/* Pull a page off the txn's spill list, if present.
- *
- * If a page being referenced was spilled to disk in this txn, bring
- * it back and make it dirty/writable again.
- *
- * [in] txn   the transaction handle.
- * [in] mp    the page being referenced. It must not be dirty.
- * [out] ret  the writable page, if any.
- *            ret is unchanged if mp wasn't spilled. */
-static int __must_check_result mdbx_page_unspill(MDBX_txn *txn, MDBX_page *mp,
-                                                 MDBX_page **ret) {
-  mdbx_tassert(txn, !IS_DIRTY(mp));
-  const pgno_t spilled_pgno = mp->mp_pgno << 1;
-  const MDBX_txn *scan = txn;
-  do {
-    if ((scan->mt_flags & MDBX_TXN_SPILLS) == 0)
-      break;
-    if (!scan->tw.spill_pages)
-      continue;
-    const unsigned si = mdbx_pnl_exist(scan->tw.spill_pages, spilled_pgno);
-    if (!si)
-      continue;
-    const unsigned npages = IS_OVERFLOW(mp) ? mp->mp_pages : 1;
-    MDBX_page *np = mp;
-    if ((txn->mt_flags & MDBX_WRITEMAP) == 0) {
-      np = mdbx_page_malloc(txn, npages);
-      if (unlikely(!np))
-        return MDBX_ENOMEM;
-      if (likely(npages == 1))
-        mdbx_page_copy(np, mp, txn->mt_env->me_psize);
-      else
-        memcpy(np, mp, pgno2bytes(txn->mt_env, npages));
-    }
-    mdbx_debug("unspill page %" PRIaPGNO, mp->mp_pgno);
-    if (scan == txn) {
-      /* If in current txn, this page is no longer spilled.
-       * If it happens to be the last page, truncate the spill list.
-       * Otherwise mark it as deleted by setting the LSB. */
-      mdbx_spill_remove(txn, si, npages);
-    } /* otherwise, if belonging to a parent txn, the
-       * page remains spilled until child commits */
-
-    int rc = mdbx_page_dirty(txn, np);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      if ((txn->mt_flags & MDBX_WRITEMAP) == 0)
-        mdbx_dpage_free(txn->mt_env, np, npages);
-      return rc;
-    }
-    *ret = np;
-    break;
-  } while ((scan = scan->mt_parent) != nullptr);
-  return MDBX_SUCCESS;
-}
-
-/* Touch a page: make it dirty and re-insert into tree with updated pgno.
- * Set MDBX_TXN_ERROR on failure.
- *
- * [in] mc  cursor pointing to the page to be touched
- *
- * Returns 0 on success, non-zero on failure. */
-__hot static int mdbx_page_touch(MDBX_cursor *mc) {
-  MDBX_page *const mp = mc->mc_pg[mc->mc_top], *np;
-  MDBX_txn *txn = mc->mc_txn;
-  MDBX_cursor *m2, *m3;
-  pgno_t pgno;
-  int rc;
-
-  if (mdbx_assert_enabled()) {
-    if (mc->mc_dbi >= CORE_DBS) {
-      if (mc->mc_flags & C_SUB) {
-        MDBX_xcursor *mx = container_of(mc->mc_db, MDBX_xcursor, mx_db);
-        MDBX_cursor_couple *couple =
-            container_of(mx, MDBX_cursor_couple, inner);
-        mdbx_cassert(mc, mc->mc_db == &couple->outer.mc_xcursor->mx_db);
-        mdbx_cassert(mc, mc->mc_dbx == &couple->outer.mc_xcursor->mx_dbx);
-        mdbx_cassert(mc, *couple->outer.mc_dbistate & DBI_DIRTY);
-      } else {
-        mdbx_cassert(mc, *mc->mc_dbistate & DBI_DIRTY);
-      }
-      mdbx_cassert(mc, mc->mc_txn->mt_flags & MDBX_TXN_DIRTY);
-    }
-    mdbx_cassert(mc, !IS_OVERFLOW(mp));
-    mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  }
-
-  if (!IS_DIRTY(mp)) {
-    if (txn->mt_flags & MDBX_TXN_SPILLS) {
-      np = NULL;
-      rc = mdbx_page_unspill(txn, mp, &np);
-      if (unlikely(rc))
-        goto fail;
-      if (likely(np))
-        goto done;
-    }
-
-    if (unlikely((rc = mdbx_pnl_need(&txn->tw.retired_pages, 1)) ||
-                 (rc = mdbx_page_alloc(mc, 1, &np, MDBX_ALLOC_ALL))))
-      goto fail;
-
-    pgno = np->mp_pgno;
-    mdbx_debug("touched db %d page %" PRIaPGNO " -> %" PRIaPGNO, DDBI(mc),
-               mp->mp_pgno, pgno);
-    mdbx_cassert(mc, mp->mp_pgno != pgno);
-    mdbx_pnl_xappend(txn->tw.retired_pages, mp->mp_pgno);
-    /* Update the parent page, if any, to point to the new page */
-    if (mc->mc_top) {
-      MDBX_page *parent = mc->mc_pg[mc->mc_top - 1];
-      MDBX_node *node = page_node(parent, mc->mc_ki[mc->mc_top - 1]);
-      node_set_pgno(node, pgno);
-    } else {
-      mc->mc_db->md_root = pgno;
-    }
-  } else if (txn->mt_parent && !IS_SUBP(mp)) {
-    mdbx_tassert(txn, (txn->mt_env->me_flags & MDBX_WRITEMAP) == 0);
-    pgno = mp->mp_pgno;
-    /* If txn has a parent, make sure the page is in our dirty list. */
-    const MDBX_page *const dp = mdbx_dpl_find(txn->tw.dirtylist, pgno);
-    if (dp) {
-      if (unlikely(mp != dp)) { /* bad cursor? */
-        mdbx_error("wrong page 0x%p #%" PRIaPGNO
-                   " in the dirtylist, expecting %p",
-                   __Wpedantic_format_voidptr(dp), pgno,
-                   __Wpedantic_format_voidptr(mp));
-        mc->mc_flags &= ~(C_INITIALIZED | C_EOF);
-        rc = MDBX_PROBLEM;
-        goto fail;
-      }
-      return MDBX_SUCCESS;
-    }
-
-    mdbx_debug("clone db %d page %" PRIaPGNO, DDBI(mc), mp->mp_pgno);
-    mdbx_cassert(mc, txn->tw.dirtylist->length <=
-                         MDBX_PGL_LIMIT + MDBX_PNL_GRANULATE);
-    /* No - copy it */
-    np = mdbx_page_malloc(txn, 1);
-    if (unlikely(!np)) {
-      rc = MDBX_ENOMEM;
-      goto fail;
-    }
-    /* insert a clone of parent's dirty page, so don't touch dirtyroom */
-    rc = mdbx_dpl_append(txn, pgno, np);
-    if (unlikely(rc)) {
-      mdbx_dpage_free(txn->mt_env, np, 1);
-      goto fail;
-    }
-
-    np->mp_pgno = pgno;
-    np->mp_txnid = INVALID_TXNID;
-    np->mp_flags |= P_DIRTY;
-    mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  } else {
-    return MDBX_SUCCESS;
-  }
-
-  mdbx_page_copy(np, mp, txn->mt_env->me_psize);
-  np->mp_pgno = pgno;
-  np->mp_txnid = INVALID_TXNID;
-  np->mp_flags |= P_DIRTY;
-
-done:
-  /* Adjust cursors pointing to mp */
-  mc->mc_pg[mc->mc_top] = np;
-  m2 = txn->tw.cursors[mc->mc_dbi];
-  if (mc->mc_flags & C_SUB) {
-    for (; m2; m2 = m2->mc_next) {
-      m3 = &m2->mc_xcursor->mx_cursor;
-      if (m3->mc_snum < mc->mc_snum)
-        continue;
-      if (m3->mc_pg[mc->mc_top] == mp)
-        m3->mc_pg[mc->mc_top] = np;
-    }
-  } else {
-    for (; m2; m2 = m2->mc_next) {
-      if (m2->mc_snum < mc->mc_snum)
-        continue;
-      if (m2 == mc)
-        continue;
-      if (m2->mc_pg[mc->mc_top] == mp) {
-        m2->mc_pg[mc->mc_top] = np;
-        if (XCURSOR_INITED(m2) && IS_LEAF(np))
-          XCURSOR_REFRESH(m2, np, m2->mc_ki[mc->mc_top]);
-      }
-    }
-  }
-  return MDBX_SUCCESS;
-
-fail:
-  txn->mt_flags |= MDBX_TXN_ERROR;
-  return rc;
-}
-
-__cold static int mdbx_env_sync_internal(MDBX_env *env, bool force,
-                                         bool nonblock) {
-  unsigned flags = env->me_flags & ~MDBX_NOMETASYNC;
-  if (unlikely(flags & (MDBX_RDONLY | MDBX_FATAL_ERROR)))
-    return MDBX_EACCESS;
-
-  if (unlikely(!env->me_map))
-    return MDBX_EPERM;
-
-  int rc = MDBX_RESULT_TRUE /* means "nothing to sync" */;
-  bool need_unlock = false;
-  if (nonblock && atomic_load32(env->me_unsynced_pages, mo_AcquireRelease) == 0)
-    goto fastpath;
-
-  const bool outside_txn = (env->me_txn0->mt_owner != mdbx_thread_self());
-  if (outside_txn) {
-    int err = mdbx_txn_lock(env, nonblock);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-    need_unlock = true;
-  }
-
-  const MDBX_meta *head = mdbx_meta_head(env);
-  pgno_t unsynced_pages = atomic_load32(env->me_unsynced_pages, mo_Relaxed);
-  if (!META_IS_STEADY(head) || unsynced_pages) {
-    const pgno_t autosync_threshold =
-        atomic_load32(env->me_autosync_threshold, mo_Relaxed);
-    const uint64_t autosync_period =
-        atomic_load64(env->me_autosync_period, mo_Relaxed);
-    if (force || (autosync_threshold && unsynced_pages >= autosync_threshold) ||
-        (autosync_period &&
-         mdbx_osal_monotime() -
-                 atomic_load64(env->me_sync_timestamp, mo_Relaxed) >=
-             autosync_period))
-      flags &= MDBX_WRITEMAP /* clear flags for full steady sync */;
-
-    if (outside_txn) {
-      if (unsynced_pages > /* FIXME: define threshold */ 16 &&
-          (flags & MDBX_SAFE_NOSYNC) == 0) {
-        mdbx_assert(env, ((flags ^ env->me_flags) & MDBX_WRITEMAP) == 0);
-        const size_t usedbytes = pgno_align2os_bytes(env, head->mm_geo.next);
-
-        mdbx_txn_unlock(env);
-
-        /* LY: pre-sync without holding lock to reduce latency for writer(s) */
-        int err = (flags & MDBX_WRITEMAP)
-                      ? mdbx_msync(&env->me_dxb_mmap, 0, usedbytes, false)
-                      : mdbx_fsync(env->me_lazy_fd, MDBX_SYNC_DATA);
-        if (unlikely(err != MDBX_SUCCESS))
-          return err;
-
-        err = mdbx_txn_lock(env, nonblock);
-        if (unlikely(err != MDBX_SUCCESS))
-          return err;
-
-        /* LY: head and unsynced_pages may be changed. */
-        head = mdbx_meta_head(env);
-        unsynced_pages = atomic_load32(env->me_unsynced_pages, mo_Relaxed);
-      }
-      env->me_txn0->mt_txnid = meta_txnid(env, head, false);
-      mdbx_find_oldest(env->me_txn0);
-      rc = MDBX_RESULT_FALSE /* means "some data was synced" */;
-    }
-
-    if (!META_IS_STEADY(head) ||
-        ((flags & MDBX_SAFE_NOSYNC) == 0 && unsynced_pages)) {
-      mdbx_debug("meta-head %" PRIaPGNO ", %s, sync_pending %" PRIaPGNO,
-                 data_page(head)->mp_pgno, mdbx_durable_str(head),
-                 unsynced_pages);
-      MDBX_meta meta = *head;
-      int err = mdbx_sync_locked(env, flags | MDBX_SHRINK_ALLOWED, &meta);
-      if (unlikely(err != MDBX_SUCCESS)) {
-        if (need_unlock)
-          mdbx_txn_unlock(env);
-        return err;
-      }
-      rc = MDBX_RESULT_FALSE /* means "some data was synced" */;
-    }
-  }
-
-fastpath:
-  /* LY: sync meta-pages if MDBX_NOMETASYNC enabled
-   *     and someone was not synced above. */
-  if (rc == MDBX_RESULT_TRUE && (env->me_flags & MDBX_NOMETASYNC) != 0) {
-    const txnid_t head_txnid = mdbx_recent_committed_txnid(env);
-    if (atomic_load32(env->me_meta_sync_txnid, mo_Relaxed) !=
-        (uint32_t)head_txnid) {
-      rc = (flags & MDBX_WRITEMAP)
-               ? mdbx_msync(&env->me_dxb_mmap, 0,
-                            pgno_align2os_bytes(env, NUM_METAS), false)
-               : mdbx_fsync(env->me_lazy_fd, MDBX_SYNC_DATA | MDBX_SYNC_IODQ);
-      if (likely(rc == MDBX_SUCCESS))
-        atomic_store32(env->me_meta_sync_txnid, (uint32_t)head_txnid,
-                       mo_Relaxed);
-    }
-  }
-  if (need_unlock)
-    mdbx_txn_unlock(env);
-  return rc;
-}
-
-static __inline int check_env(const MDBX_env *env) {
-  if (unlikely(!env))
-    return MDBX_EINVAL;
-
-  if (unlikely(env->me_signature.weak != MDBX_ME_SIGNATURE))
-    return MDBX_EBADSIGN;
-
-#if MDBX_ENV_CHECKPID
-  if (unlikely(env->me_pid != mdbx_getpid())) {
-    ((MDBX_env *)env)->me_flags |= MDBX_FATAL_ERROR;
-    return MDBX_PANIC;
-  }
-#endif /* MDBX_ENV_CHECKPID */
-
-  if (unlikely(env->me_flags & MDBX_FATAL_ERROR))
-    return MDBX_PANIC;
-
-  return MDBX_SUCCESS;
-}
-
-__cold int mdbx_env_sync_ex(MDBX_env *env, bool force, bool nonblock) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  return mdbx_env_sync_internal(env, force, nonblock);
-}
-
-__cold int mdbx_env_sync(MDBX_env *env) { return __inline_mdbx_env_sync(env); }
-
-__cold int mdbx_env_sync_poll(MDBX_env *env) {
-  return __inline_mdbx_env_sync_poll(env);
-}
-
-/* Back up parent txn's cursors, then grab the originals for tracking */
-static int mdbx_cursor_shadow(MDBX_txn *parent, MDBX_txn *nested) {
-  for (int i = parent->mt_numdbs; --i >= 0;) {
-    nested->tw.cursors[i] = NULL;
-    MDBX_cursor *mc = parent->tw.cursors[i];
-    if (mc != NULL) {
-      size_t size = mc->mc_xcursor ? sizeof(MDBX_cursor) + sizeof(MDBX_xcursor)
-                                   : sizeof(MDBX_cursor);
-      for (MDBX_cursor *bk; mc; mc = bk->mc_next) {
-        bk = mc;
-        if (mc->mc_signature != MDBX_MC_LIVE)
-          continue;
-        bk = mdbx_malloc(size);
-        if (unlikely(!bk))
-          return MDBX_ENOMEM;
-        *bk = *mc;
-        mc->mc_backup = bk;
-        /* Kill pointers into src to reduce abuse: The
-         * user may not use mc until dst ends. But we need a valid
-         * txn pointer here for cursor fixups to keep working. */
-        mc->mc_txn = nested;
-        mc->mc_db = &nested->mt_dbs[i];
-        mc->mc_dbistate = &nested->mt_dbistate[i];
-        MDBX_xcursor *mx = mc->mc_xcursor;
-        if (mx != NULL) {
-          *(MDBX_xcursor *)(bk + 1) = *mx;
-          mx->mx_cursor.mc_txn = nested;
-        }
-        mc->mc_next = nested->tw.cursors[i];
-        nested->tw.cursors[i] = mc;
-      }
-    }
-  }
-  return MDBX_SUCCESS;
-}
-
-/* Close this write txn's cursors, give parent txn's cursors back to parent.
- *
- * [in] txn     the transaction handle.
- * [in] merge   true to keep changes to parent cursors, false to revert.
- *
- * Returns 0 on success, non-zero on failure. */
-static void mdbx_cursors_eot(MDBX_txn *txn, const bool merge) {
-  mdbx_tassert(txn, (txn->mt_flags & MDBX_TXN_RDONLY) == 0);
-  for (int i = txn->mt_numdbs; --i >= 0;) {
-    MDBX_cursor *next, *mc = txn->tw.cursors[i];
-    if (!mc)
-      continue;
-    txn->tw.cursors[i] = NULL;
-    do {
-      const unsigned stage = mc->mc_signature;
-      MDBX_cursor *bk = mc->mc_backup;
-      next = mc->mc_next;
-      mdbx_ensure(txn->mt_env,
-                  stage == MDBX_MC_LIVE || (stage == MDBX_MC_WAIT4EOT && bk));
-      mdbx_cassert(mc, mc->mc_dbi == (unsigned)i);
-      if (bk) {
-        MDBX_xcursor *mx = mc->mc_xcursor;
-        mdbx_cassert(mc, mx == bk->mc_xcursor);
-        mdbx_tassert(txn, txn->mt_parent != NULL);
-        mdbx_ensure(txn->mt_env, bk->mc_signature == MDBX_MC_LIVE);
-        if (stage == MDBX_MC_WAIT4EOT /* Cursor was closed by user */)
-          mc->mc_signature = stage /* Promote closed state to parent txn */;
-        else if (merge) {
-          /* Restore pointers to parent txn */
-          mc->mc_next = bk->mc_next;
-          mc->mc_backup = bk->mc_backup;
-          mc->mc_txn = bk->mc_txn;
-          mc->mc_db = bk->mc_db;
-          mc->mc_dbistate = bk->mc_dbistate;
-          if (mx) {
-            if (mx != bk->mc_xcursor) {
-              *bk->mc_xcursor = *mx;
-              mx = bk->mc_xcursor;
-            }
-            mx->mx_cursor.mc_txn = bk->mc_txn;
-          }
-        } else {
-          /* Restore from backup, i.e. rollback/abort nested txn */
-          *mc = *bk;
-          if (mx)
-            *mx = *(MDBX_xcursor *)(bk + 1);
-        }
-        bk->mc_signature = 0;
-        mdbx_free(bk);
-      } else {
-        mdbx_ensure(txn->mt_env, stage == MDBX_MC_LIVE);
-        mc->mc_signature = MDBX_MC_READY4CLOSE /* Cursor may be reused */;
-        mc->mc_flags = 0 /* reset C_UNTRACK */;
-      }
-    } while ((mc = next) != NULL);
-  }
-}
-
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-/* Find largest mvcc-snapshot still referenced by this process. */
-static pgno_t mdbx_find_largest_this(MDBX_env *env, pgno_t largest) {
-  MDBX_lockinfo *const lck = env->me_lck;
-  if (likely(lck != NULL /* exclusive mode */)) {
-    const unsigned snap_nreaders =
-        atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-    for (unsigned i = 0; i < snap_nreaders; ++i) {
-    retry:
-      if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease) ==
-          env->me_pid) {
-        /* mdbx_jitter4testing(true); */
-        const pgno_t snap_pages = atomic_load32(
-            &lck->mti_readers[i].mr_snapshot_pages_used, mo_Relaxed);
-        const txnid_t snap_txnid = safe64_read(&lck->mti_readers[i].mr_txnid);
-        if (unlikely(
-                snap_pages !=
-                    atomic_load32(&lck->mti_readers[i].mr_snapshot_pages_used,
-                                  mo_AcquireRelease) ||
-                snap_txnid != safe64_read(&lck->mti_readers[i].mr_txnid)))
-          goto retry;
-        if (largest < snap_pages &&
-            atomic_load64(&lck->mti_oldest_reader, mo_AcquireRelease) <=
-                /* ignore pending updates */ snap_txnid &&
-            snap_txnid <= MAX_TXNID)
-          largest = snap_pages;
-      }
-    }
-  }
-  return largest;
-}
-
-static void mdbx_txn_valgrind(MDBX_env *env, MDBX_txn *txn) {
-#if !defined(__SANITIZE_ADDRESS__)
-  if (!RUNNING_ON_VALGRIND)
-    return;
-#endif
-
-  if (txn) { /* transaction start */
-    if (env->me_poison_edge < txn->mt_next_pgno)
-      env->me_poison_edge = txn->mt_next_pgno;
-    VALGRIND_MAKE_MEM_DEFINED(env->me_map, pgno2bytes(env, txn->mt_next_pgno));
-    ASAN_UNPOISON_MEMORY_REGION(env->me_map,
-                                pgno2bytes(env, txn->mt_next_pgno));
-    /* don't touch more, it should be already poisoned */
-  } else { /* transaction end */
-    bool should_unlock = false;
-    pgno_t last = MAX_PAGENO;
-    if (env->me_txn0 && env->me_txn0->mt_owner == mdbx_thread_self()) {
-      /* inside write-txn */
-      MDBX_meta *head = mdbx_meta_head(env);
-      last = head->mm_geo.next;
-    } else if (env->me_flags & MDBX_RDONLY) {
-      /* read-only mode, no write-txn, no wlock mutex */
-      last = NUM_METAS;
-    } else if (mdbx_txn_lock(env, true) == MDBX_SUCCESS) {
-      /* no write-txn */
-      last = NUM_METAS;
-      should_unlock = true;
-    } else {
-      /* write txn is running, therefore shouldn't poison any memory range */
-      return;
-    }
-
-    last = mdbx_find_largest_this(env, last);
-    const pgno_t edge = env->me_poison_edge;
-    if (edge > last) {
-      mdbx_assert(env, last >= NUM_METAS);
-      env->me_poison_edge = last;
-      VALGRIND_MAKE_MEM_NOACCESS(env->me_map + pgno2bytes(env, last),
-                                 pgno2bytes(env, edge - last));
-      ASAN_POISON_MEMORY_REGION(env->me_map + pgno2bytes(env, last),
-                                pgno2bytes(env, edge - last));
-    }
-    if (should_unlock)
-      mdbx_txn_unlock(env);
-  }
-}
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-
-typedef struct {
-  int err;
-  MDBX_reader *rslot;
-} bind_rslot_result;
-
-static bind_rslot_result bind_rslot(MDBX_env *env, const uintptr_t tid) {
-  mdbx_assert(env, env->me_lck);
-  mdbx_assert(env, env->me_lck->mti_magic_and_version == MDBX_LOCK_MAGIC);
-  mdbx_assert(env, env->me_lck->mti_os_and_format == MDBX_LOCK_FORMAT);
-
-  bind_rslot_result result = {mdbx_rdt_lock(env), nullptr};
-  if (unlikely(MDBX_IS_ERROR(result.err)))
-    return result;
-  if (unlikely(env->me_flags & MDBX_FATAL_ERROR)) {
-    mdbx_rdt_unlock(env);
-    result.err = MDBX_PANIC;
-    return result;
-  }
-  if (unlikely(!env->me_map)) {
-    mdbx_rdt_unlock(env);
-    result.err = MDBX_EPERM;
-    return result;
-  }
-
-  if (unlikely(env->me_live_reader != env->me_pid)) {
-    result.err = mdbx_rpid_set(env);
-    if (unlikely(result.err != MDBX_SUCCESS)) {
-      mdbx_rdt_unlock(env);
-      return result;
-    }
-    env->me_live_reader = env->me_pid;
-  }
-
-  result.err = MDBX_SUCCESS;
-  unsigned slot, nreaders;
-  while (1) {
-    nreaders = atomic_load32(&env->me_lck->mti_numreaders, mo_Relaxed);
-    for (slot = 0; slot < nreaders; slot++)
-      if (atomic_load32(&env->me_lck->mti_readers[slot].mr_pid, mo_Relaxed) ==
-          0)
-        break;
-
-    if (likely(slot < env->me_maxreaders))
-      break;
-
-    result.err = mdbx_cleanup_dead_readers(env, true, NULL);
-    if (result.err != MDBX_RESULT_TRUE) {
-      mdbx_rdt_unlock(env);
-      result.err =
-          (result.err == MDBX_SUCCESS) ? MDBX_READERS_FULL : result.err;
-      return result;
-    }
-  }
-
-  result.rslot = &env->me_lck->mti_readers[slot];
-  /* Claim the reader slot, carefully since other code
-   * uses the reader table un-mutexed: First reset the
-   * slot, next publish it in lck->mti_numreaders.  After
-   * that, it is safe for mdbx_env_close() to touch it.
-   * When it will be closed, we can finally claim it. */
-  atomic_store32(&result.rslot->mr_pid, 0, mo_Relaxed);
-  safe64_reset(&result.rslot->mr_txnid, true);
-  if (slot == nreaders)
-    atomic_store32(&env->me_lck->mti_numreaders, ++nreaders, mo_Relaxed);
-  atomic_store64(&result.rslot->mr_tid, (env->me_flags & MDBX_NOTLS) ? 0 : tid,
-                 mo_Relaxed);
-  atomic_store32(&result.rslot->mr_pid, env->me_pid, mo_Relaxed);
-  mdbx_rdt_unlock(env);
-
-  if (likely(env->me_flags & MDBX_ENV_TXKEY)) {
-    mdbx_assert(env, env->me_live_reader == env->me_pid);
-    thread_rthc_set(env->me_txkey, result.rslot);
-  }
-  return result;
-}
-
-__cold int mdbx_thread_register(const MDBX_env *env) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!env->me_lck))
-    return (env->me_flags & MDBX_EXCLUSIVE) ? MDBX_EINVAL : MDBX_EPERM;
-
-  if (unlikely((env->me_flags & MDBX_ENV_TXKEY) == 0)) {
-    mdbx_assert(env, !env->me_lck || (env->me_flags & MDBX_NOTLS));
-    return MDBX_EINVAL /* MDBX_NOTLS mode */;
-  }
-
-  mdbx_assert(env, (env->me_flags & (MDBX_NOTLS | MDBX_ENV_TXKEY |
-                                     MDBX_EXCLUSIVE)) == MDBX_ENV_TXKEY);
-  MDBX_reader *r = thread_rthc_get(env->me_txkey);
-  if (unlikely(r != NULL)) {
-    mdbx_assert(env, r->mr_pid.weak == env->me_pid);
-    mdbx_assert(env, r->mr_tid.weak == mdbx_thread_self());
-    if (unlikely(r->mr_pid.weak != env->me_pid))
-      return MDBX_BAD_RSLOT;
-    return MDBX_RESULT_TRUE /* already registered */;
-  }
-
-  const uintptr_t tid = mdbx_thread_self();
-  if (env->me_txn0 && unlikely(env->me_txn0->mt_owner == tid))
-    return MDBX_TXN_OVERLAPPING;
-  return bind_rslot((MDBX_env *)env, tid).err;
-}
-
-__cold int mdbx_thread_unregister(const MDBX_env *env) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!env->me_lck))
-    return MDBX_RESULT_TRUE;
-
-  if (unlikely((env->me_flags & MDBX_ENV_TXKEY) == 0)) {
-    mdbx_assert(env, !env->me_lck || (env->me_flags & MDBX_NOTLS));
-    return MDBX_RESULT_TRUE /* MDBX_NOTLS mode */;
-  }
-
-  mdbx_assert(env, (env->me_flags & (MDBX_NOTLS | MDBX_ENV_TXKEY |
-                                     MDBX_EXCLUSIVE)) == MDBX_ENV_TXKEY);
-  MDBX_reader *r = thread_rthc_get(env->me_txkey);
-  if (unlikely(r == NULL))
-    return MDBX_RESULT_TRUE /* not registered */;
-
-  mdbx_assert(env, r->mr_pid.weak == env->me_pid);
-  mdbx_assert(env, r->mr_tid.weak == mdbx_thread_self());
-  if (unlikely(r->mr_pid.weak != env->me_pid ||
-               r->mr_tid.weak != mdbx_thread_self()))
-    return MDBX_BAD_RSLOT;
-
-  if (unlikely(r->mr_txnid.weak < SAFE64_INVALID_THRESHOLD))
-    return MDBX_BUSY /* transaction is still active */;
-
-  atomic_store32(&r->mr_pid, 0, mo_AcquireRelease);
-  atomic_store32(&env->me_lck->mti_readers_refresh_flag, true, mo_Relaxed);
-  thread_rthc_set(env->me_txkey, nullptr);
-  return MDBX_SUCCESS;
-}
-
-/* Common code for mdbx_txn_begin() and mdbx_txn_renew(). */
-static int mdbx_txn_renew0(MDBX_txn *txn, const unsigned flags) {
-  MDBX_env *env = txn->mt_env;
-  int rc;
-
-#if MDBX_ENV_CHECKPID
-  if (unlikely(env->me_pid != mdbx_getpid())) {
-    env->me_flags |= MDBX_FATAL_ERROR;
-    return MDBX_PANIC;
-  }
-#endif /* MDBX_ENV_CHECKPID */
-
-  STATIC_ASSERT(sizeof(MDBX_reader) == 32);
-#if MDBX_LOCKING > 0
-  STATIC_ASSERT(offsetof(MDBX_lockinfo, mti_wlock) % MDBX_CACHELINE_SIZE == 0);
-  STATIC_ASSERT(offsetof(MDBX_lockinfo, mti_rlock) % MDBX_CACHELINE_SIZE == 0);
-#else
-  STATIC_ASSERT(
-      offsetof(MDBX_lockinfo, mti_oldest_reader) % MDBX_CACHELINE_SIZE == 0);
-  STATIC_ASSERT(offsetof(MDBX_lockinfo, mti_numreaders) % MDBX_CACHELINE_SIZE ==
-                0);
-#endif /* MDBX_LOCKING */
-  STATIC_ASSERT(offsetof(MDBX_lockinfo, mti_readers) % MDBX_CACHELINE_SIZE ==
-                0);
-
-  const uintptr_t tid = mdbx_thread_self();
-  if (flags & MDBX_TXN_RDONLY) {
-    mdbx_assert(env, (flags & ~(MDBX_TXN_RO_BEGIN_FLAGS | MDBX_WRITEMAP)) == 0);
-    txn->mt_flags =
-        MDBX_TXN_RDONLY | (env->me_flags & (MDBX_NOTLS | MDBX_WRITEMAP));
-    MDBX_reader *r = txn->to.reader;
-    STATIC_ASSERT(sizeof(uintptr_t) <= sizeof(r->mr_tid));
-    if (likely(env->me_flags & MDBX_ENV_TXKEY)) {
-      mdbx_assert(env, !(env->me_flags & MDBX_NOTLS));
-      r = thread_rthc_get(env->me_txkey);
-      if (likely(r)) {
-        if (unlikely(!r->mr_pid.weak) &&
-            (mdbx_runtime_flags & MDBX_DBG_LEGACY_MULTIOPEN)) {
-          thread_rthc_set(env->me_txkey, nullptr);
-          r = nullptr;
-        } else {
-          mdbx_assert(env, r->mr_pid.weak == env->me_pid);
-          mdbx_assert(env, r->mr_tid.weak == mdbx_thread_self());
-        }
-      }
-    } else {
-      mdbx_assert(env, !env->me_lck || (env->me_flags & MDBX_NOTLS));
-    }
-
-    if (likely(r)) {
-      if (unlikely(r->mr_pid.weak != env->me_pid ||
-                   r->mr_txnid.weak < SAFE64_INVALID_THRESHOLD))
-        return MDBX_BAD_RSLOT;
-    } else if (env->me_lck) {
-      bind_rslot_result brs = bind_rslot(env, tid);
-      if (unlikely(brs.err != MDBX_SUCCESS))
-        return brs.err;
-      r = brs.rslot;
-    }
-    txn->to.reader = r;
-    if (flags & (MDBX_TXN_RDONLY_PREPARE - MDBX_TXN_RDONLY)) {
-      mdbx_assert(env, txn->mt_txnid == 0);
-      mdbx_assert(env, txn->mt_owner == 0);
-      mdbx_assert(env, txn->mt_numdbs == 0);
-      if (likely(r)) {
-        mdbx_assert(env, r->mr_snapshot_pages_used.weak == 0);
-        mdbx_assert(env, r->mr_txnid.weak >= SAFE64_INVALID_THRESHOLD);
-        atomic_store32(&r->mr_snapshot_pages_used, 0, mo_Relaxed);
-      }
-      txn->mt_flags = MDBX_TXN_RDONLY | MDBX_TXN_FINISHED;
-      return MDBX_SUCCESS;
-    }
-
-    /* Seek & fetch the last meta */
-    if (likely(/* not recovery mode */ env->me_stuck_meta < 0)) {
-      while (1) {
-        MDBX_meta *const meta = mdbx_meta_head(env);
-        mdbx_jitter4testing(false);
-        const txnid_t snap = mdbx_meta_txnid_fluid(env, meta);
-        mdbx_jitter4testing(false);
-        if (likely(r)) {
-          safe64_reset(&r->mr_txnid, false);
-          atomic_store32(&r->mr_snapshot_pages_used, meta->mm_geo.next,
-                         mo_Relaxed);
-          atomic_store64(&r->mr_snapshot_pages_retired,
-                         unaligned_peek_u64(4, meta->mm_pages_retired),
-                         mo_Relaxed);
-          safe64_write(&r->mr_txnid, snap);
-          mdbx_jitter4testing(false);
-          mdbx_assert(env, r->mr_pid.weak == mdbx_getpid());
-          mdbx_assert(
-              env, r->mr_tid.weak ==
-                       ((env->me_flags & MDBX_NOTLS) ? 0 : mdbx_thread_self()));
-          mdbx_assert(env, r->mr_txnid.weak == snap);
-          atomic_store32(&env->me_lck->mti_readers_refresh_flag, true,
-                         mo_AcquireRelease);
-        }
-        mdbx_jitter4testing(true);
-
-        /* Snap the state from current meta-head */
-        txn->mt_txnid = snap;
-        txn->mt_geo = meta->mm_geo;
-        memcpy(txn->mt_dbs, meta->mm_dbs, CORE_DBS * sizeof(MDBX_db));
-        txn->mt_canary = meta->mm_canary;
-
-        /* LY: Retry on a race, ITS#7970. */
-        if (likely(meta == mdbx_meta_head(env) &&
-                   snap == mdbx_meta_txnid_fluid(env, meta) &&
-                   snap >= atomic_load64(env->me_oldest, mo_AcquireRelease))) {
-          mdbx_jitter4testing(false);
-          break;
-        }
-      }
-    } else {
-      /* recovery mode */
-      MDBX_meta *const meta = METAPAGE(env, env->me_stuck_meta);
-      txn->mt_txnid = mdbx_meta_txnid_stable(env, meta);
-      txn->mt_geo = meta->mm_geo;
-      memcpy(txn->mt_dbs, meta->mm_dbs, CORE_DBS * sizeof(MDBX_db));
-      txn->mt_canary = meta->mm_canary;
-      if (likely(r)) {
-        atomic_store32(&r->mr_snapshot_pages_used, meta->mm_geo.next,
-                       mo_Relaxed);
-        atomic_store64(&r->mr_snapshot_pages_retired,
-                       unaligned_peek_u64(4, meta->mm_pages_retired),
-                       mo_Relaxed);
-        atomic_store64(&r->mr_txnid, txn->mt_txnid, mo_AcquireRelease);
-        mdbx_jitter4testing(false);
-        mdbx_assert(env, r->mr_pid.weak == mdbx_getpid());
-        mdbx_assert(
-            env, r->mr_tid.weak ==
-                     ((env->me_flags & MDBX_NOTLS) ? 0 : mdbx_thread_self()));
-        mdbx_assert(env, r->mr_txnid.weak == txn->mt_txnid);
-        atomic_store32(&env->me_lck->mti_readers_refresh_flag, true,
-                       mo_AcquireRelease);
-      }
-    }
-
-    if (unlikely(txn->mt_txnid < MIN_TXNID || txn->mt_txnid > MAX_TXNID)) {
-      mdbx_error("%s", "environment corrupted by died writer, must shutdown!");
-      rc = MDBX_CORRUPTED;
-      goto bailout;
-    }
-    mdbx_assert(env, txn->mt_txnid >= env->me_oldest->weak);
-    txn->mt_dbxs = env->me_dbxs; /* mostly static anyway */
-    mdbx_ensure(env,
-                txn->mt_txnid >=
-                    /* paranoia is appropriate here */ env->me_oldest->weak);
-    txn->mt_numdbs = env->me_numdbs;
-  } else {
-    mdbx_assert(env, (flags & ~(MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_SPILLS |
-                                MDBX_WRITEMAP)) == 0);
-    if (unlikely(txn->mt_owner == tid ||
-                 /* not recovery mode */ env->me_stuck_meta >= 0))
-      return MDBX_BUSY;
-    MDBX_lockinfo *const lck = env->me_lck;
-    if (lck && (env->me_flags & MDBX_NOTLS) == 0 &&
-        (mdbx_runtime_flags & MDBX_DBG_LEGACY_OVERLAP) == 0) {
-      const unsigned snap_nreaders =
-          atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-      for (unsigned i = 0; i < snap_nreaders; ++i) {
-        if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_Relaxed) ==
-                env->me_pid &&
-            unlikely(atomic_load64(&lck->mti_readers[i].mr_tid, mo_Relaxed) ==
-                     tid)) {
-          const txnid_t txnid = safe64_read(&lck->mti_readers[i].mr_txnid);
-          if (txnid >= MIN_TXNID && txnid <= MAX_TXNID)
-            return MDBX_TXN_OVERLAPPING;
-        }
-      }
-    }
-
-    /* Not yet touching txn == env->me_txn0, it may be active */
-    mdbx_jitter4testing(false);
-    rc = mdbx_txn_lock(env, F_ISSET(flags, MDBX_TXN_TRY));
-    if (unlikely(rc))
-      return rc;
-    if (unlikely(env->me_flags & MDBX_FATAL_ERROR)) {
-      mdbx_txn_unlock(env);
-      return MDBX_PANIC;
-    }
-#if defined(_WIN32) || defined(_WIN64)
-    if (unlikely(!env->me_map)) {
-      mdbx_txn_unlock(env);
-      return MDBX_EPERM;
-    }
-#endif /* Windows */
-
-    mdbx_jitter4testing(false);
-    MDBX_meta *meta = mdbx_meta_head(env);
-    mdbx_jitter4testing(false);
-    txn->mt_canary = meta->mm_canary;
-    const txnid_t snap = mdbx_meta_txnid_stable(env, meta);
-    txn->mt_txnid = safe64_txnid_next(snap);
-    if (unlikely(txn->mt_txnid > MAX_TXNID)) {
-      rc = MDBX_TXN_FULL;
-      mdbx_error("txnid overflow, raise %d", rc);
-      goto bailout;
-    }
-
-    txn->mt_flags = flags;
-    txn->mt_child = NULL;
-    txn->tw.loose_pages = NULL;
-    txn->tw.loose_count = 0;
-#if MDBX_ENABLE_REFUND
-    txn->tw.loose_refund_wl = 0;
-#endif /* MDBX_ENABLE_REFUND */
-    txn->tw.dirtyroom = txn->mt_env->me_options.dp_limit;
-    mdbx_dpl_clear(txn->tw.dirtylist);
-    MDBX_PNL_SIZE(txn->tw.retired_pages) = 0;
-    txn->tw.spill_pages = NULL;
-    txn->tw.spill_least_removed = 0;
-    txn->tw.last_reclaimed = 0;
-    if (txn->tw.lifo_reclaimed)
-      MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) = 0;
-    env->me_txn = txn;
-    txn->mt_numdbs = env->me_numdbs;
-    memcpy(txn->mt_dbiseqs, env->me_dbiseqs, txn->mt_numdbs * sizeof(unsigned));
-    /* Copy the DB info and flags */
-    memcpy(txn->mt_dbs, meta->mm_dbs, CORE_DBS * sizeof(MDBX_db));
-    /* Moved to here to avoid a data race in read TXNs */
-    txn->mt_geo = meta->mm_geo;
-  }
-
-  /* Setup db info */
-  mdbx_compiler_barrier();
-  for (unsigned i = CORE_DBS; i < txn->mt_numdbs; i++) {
-    const unsigned db_flags = env->me_dbflags[i];
-    txn->mt_dbs[i].md_flags = db_flags & DB_PERSISTENT_FLAGS;
-    txn->mt_dbistate[i] =
-        (db_flags & DB_VALID) ? DBI_VALID | DBI_USRVALID | DBI_STALE : 0;
-  }
-  txn->mt_dbistate[MAIN_DBI] = DBI_VALID | DBI_USRVALID;
-  txn->mt_dbistate[FREE_DBI] = DBI_VALID;
-
-  if (unlikely(env->me_flags & MDBX_FATAL_ERROR)) {
-    mdbx_warning("%s", "environment had fatal error, must shutdown!");
-    rc = MDBX_PANIC;
-  } else {
-    const size_t size =
-        pgno2bytes(env, (txn->mt_flags & MDBX_TXN_RDONLY) ? txn->mt_next_pgno
-                                                          : txn->mt_end_pgno);
-    if (unlikely(size > env->me_dxb_mmap.limit)) {
-      if (txn->mt_geo.upper > MAX_PAGENO ||
-          bytes2pgno(env, pgno2bytes(env, txn->mt_geo.upper)) !=
-              txn->mt_geo.upper) {
-        rc = MDBX_UNABLE_EXTEND_MAPSIZE;
-        goto bailout;
-      }
-      rc = mdbx_mapresize(env, txn->mt_next_pgno, txn->mt_end_pgno,
-                          txn->mt_geo.upper,
-                          (txn->mt_flags & MDBX_TXN_RDONLY) ? true : false);
-      if (rc != MDBX_SUCCESS)
-        goto bailout;
-    }
-    if (txn->mt_flags & MDBX_TXN_RDONLY) {
-#if defined(_WIN32) || defined(_WIN64)
-      if ((size > env->me_dbgeo.lower && env->me_dbgeo.shrink) ||
-          (mdbx_RunningUnderWine() &&
-           /* under Wine acquisition of remap_guard is always required,
-            * since Wine don't support section extending,
-            * i.e. in both cases unmap+map are required. */
-           size < env->me_dbgeo.upper && env->me_dbgeo.grow)) {
-        txn->mt_flags |= MDBX_SHRINK_ALLOWED;
-        mdbx_srwlock_AcquireShared(&env->me_remap_guard);
-      }
-#endif /* Windows */
-    } else {
-      env->me_dxb_mmap.current = size;
-#if defined(_WIN32) || defined(_WIN64)
-      env->me_dxb_mmap.filesize =
-          (env->me_dxb_mmap.filesize < size) ? size : env->me_dxb_mmap.filesize;
-#endif /* Windows */
-    }
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-    mdbx_txn_valgrind(env, txn);
-#endif
-    txn->mt_owner = tid;
-    return MDBX_SUCCESS;
-  }
-bailout:
-  mdbx_tassert(txn, rc != MDBX_SUCCESS);
-  mdbx_txn_end(txn, MDBX_END_SLOT | MDBX_END_FAIL_BEGIN);
-  return rc;
-}
-
-static __always_inline int check_txn(const MDBX_txn *txn, int bad_bits) {
-  if (unlikely(!txn))
-    return MDBX_EINVAL;
-
-  if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
-    return MDBX_EBADSIGN;
-
-  if (unlikely(txn->mt_flags & bad_bits))
-    return MDBX_BAD_TXN;
-
-#if MDBX_TXN_CHECKOWNER
-  if ((txn->mt_flags & MDBX_NOTLS) == 0 &&
-      unlikely(txn->mt_owner != mdbx_thread_self()))
-    return txn->mt_owner ? MDBX_THREAD_MISMATCH : MDBX_BAD_TXN;
-#endif /* MDBX_TXN_CHECKOWNER */
-
-  return MDBX_SUCCESS;
-}
-
-static __always_inline int check_txn_rw(const MDBX_txn *txn, int bad_bits) {
-  if (unlikely(!txn))
-    return MDBX_EINVAL;
-
-  if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
-    return MDBX_EBADSIGN;
-
-  if (unlikely(txn->mt_flags & bad_bits))
-    return MDBX_BAD_TXN;
-
-  if (unlikely(F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
-    return MDBX_EACCESS;
-
-#if MDBX_TXN_CHECKOWNER
-  if (unlikely(txn->mt_owner != mdbx_thread_self()))
-    return txn->mt_owner ? MDBX_THREAD_MISMATCH : MDBX_BAD_TXN;
-#endif /* MDBX_TXN_CHECKOWNER */
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_txn_renew(MDBX_txn *txn) {
-  if (unlikely(!txn))
-    return MDBX_EINVAL;
-
-  if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
-    return MDBX_EBADSIGN;
-
-  if (unlikely((txn->mt_flags & MDBX_TXN_RDONLY) == 0))
-    return MDBX_EINVAL;
-
-  int rc;
-  if (unlikely(txn->mt_owner != 0 || !(txn->mt_flags & MDBX_TXN_FINISHED))) {
-    rc = mdbx_txn_reset(txn);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  rc = mdbx_txn_renew0(txn, MDBX_TXN_RDONLY);
-  if (rc == MDBX_SUCCESS) {
-    txn->mt_owner = mdbx_thread_self();
-    mdbx_debug("renew txn %" PRIaTXN "%c %p on env %p, root page %" PRIaPGNO
-               "/%" PRIaPGNO,
-               txn->mt_txnid, (txn->mt_flags & MDBX_TXN_RDONLY) ? 'r' : 'w',
-               (void *)txn, (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root,
-               txn->mt_dbs[FREE_DBI].md_root);
-  }
-  return rc;
-}
-
-int mdbx_txn_begin(MDBX_env *env, MDBX_txn *parent, MDBX_txn_flags_t flags,
-                   MDBX_txn **ret) {
-  return __inline_mdbx_txn_begin(env, parent, flags, ret);
-}
-
-int mdbx_txn_set_userctx(MDBX_txn *txn, void *ctx) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED - MDBX_TXN_HAS_CHILD);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  txn->mt_userctx = ctx;
-  return MDBX_SUCCESS;
-}
-
-void *mdbx_txn_get_userctx(const MDBX_txn *txn) {
-  return check_txn(txn, MDBX_TXN_BLOCKED - MDBX_TXN_HAS_CHILD)
-             ? nullptr
-             : txn->mt_userctx;
-}
-
-int mdbx_txn_begin_ex(MDBX_env *env, MDBX_txn *parent, MDBX_txn_flags_t flags,
-                      MDBX_txn **ret, void *context) {
-  MDBX_txn *txn;
-  unsigned size, tsize;
-
-  if (unlikely(!ret))
-    return MDBX_EINVAL;
-  *ret = NULL;
-
-  if (unlikely((flags & ~MDBX_TXN_RW_BEGIN_FLAGS) &&
-               (flags & ~MDBX_TXN_RO_BEGIN_FLAGS)))
-    return MDBX_EINVAL;
-
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(env->me_flags & MDBX_RDONLY &
-               ~flags)) /* write txn in RDONLY env */
-    return MDBX_EACCESS;
-
-  if (unlikely(!env->me_map))
-    return MDBX_EPERM;
-
-  flags |= env->me_flags & MDBX_WRITEMAP;
-
-  if (parent) {
-    /* Nested transactions: Max 1 child, write txns only, no writemap */
-    rc = check_txn_rw(parent,
-                      MDBX_TXN_RDONLY | MDBX_WRITEMAP | MDBX_TXN_BLOCKED);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-
-    if (env->me_options.spill_parent4child_denominator) {
-      /* Spill dirty-pages of parent to provide dirtyroom for child txn */
-      rc = mdbx_txn_spill(parent, nullptr,
-                          parent->tw.dirtylist->length /
-                              env->me_options.spill_parent4child_denominator);
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-    }
-    mdbx_tassert(parent, mdbx_audit_ex(parent, 0, false) == 0);
-
-    flags |= parent->mt_flags & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_SPILLS);
-    /* Child txns save MDBX_pgstate and use own copy of cursors */
-    size = env->me_maxdbs * (sizeof(MDBX_db) + sizeof(MDBX_cursor *) + 1);
-    size += tsize = sizeof(MDBX_txn);
-  } else if (flags & MDBX_TXN_RDONLY) {
-    if (env->me_txn0 &&
-        unlikely(env->me_txn0->mt_owner == mdbx_thread_self()) &&
-        (mdbx_runtime_flags & MDBX_DBG_LEGACY_OVERLAP) == 0)
-      return MDBX_TXN_OVERLAPPING;
-    size = env->me_maxdbs * (sizeof(MDBX_db) + 1);
-    size += tsize = sizeof(MDBX_txn);
-  } else {
-    /* Reuse preallocated write txn. However, do not touch it until
-     * mdbx_txn_renew0() succeeds, since it currently may be active. */
-    txn = env->me_txn0;
-    goto renew;
-  }
-  if (unlikely((txn = mdbx_malloc(size)) == NULL)) {
-    mdbx_debug("calloc: %s", "failed");
-    return MDBX_ENOMEM;
-  }
-  memset(txn, 0, tsize);
-  txn->mt_dbxs = env->me_dbxs; /* static */
-  txn->mt_dbs = (MDBX_db *)((char *)txn + tsize);
-  txn->mt_dbistate = (uint8_t *)txn + size - env->me_maxdbs;
-  txn->mt_flags = flags;
-  txn->mt_env = env;
-
-  if (parent) {
-    mdbx_tassert(parent, mdbx_dirtylist_check(parent));
-    txn->tw.cursors = (MDBX_cursor **)(txn->mt_dbs + env->me_maxdbs);
-    txn->mt_dbiseqs = parent->mt_dbiseqs;
-    rc = mdbx_dpl_alloc(txn);
-    if (likely(rc == MDBX_SUCCESS)) {
-      const unsigned len =
-          MDBX_PNL_SIZE(parent->tw.reclaimed_pglist) + parent->tw.loose_count;
-      txn->tw.reclaimed_pglist =
-          mdbx_pnl_alloc((len > MDBX_PNL_INITIAL) ? len : MDBX_PNL_INITIAL);
-      if (unlikely(!txn->tw.reclaimed_pglist))
-        rc = MDBX_ENOMEM;
-    }
-    if (unlikely(rc != MDBX_SUCCESS)) {
-    nested_failed:
-      mdbx_pnl_free(txn->tw.reclaimed_pglist);
-      mdbx_dpl_free(txn);
-      mdbx_free(txn);
-      return rc;
-    }
-    txn->tw.dirtyroom = parent->tw.dirtyroom;
-
-    /* Move loose pages to reclaimed list */
-    if (parent->tw.loose_count) {
-      do {
-        MDBX_page *lp = parent->tw.loose_pages;
-        const unsigned di = mdbx_dpl_exist(parent->tw.dirtylist, lp->mp_pgno);
-        mdbx_tassert(parent, di && parent->tw.dirtylist->items[di].ptr == lp);
-        mdbx_tassert(parent, lp->mp_flags == (P_LOOSE | P_DIRTY));
-        rc =
-            mdbx_pnl_insert_range(&parent->tw.reclaimed_pglist, lp->mp_pgno, 1);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto nested_failed;
-        parent->tw.loose_pages = lp->mp_next;
-        /* Remove from dirty list */
-        mdbx_page_wash(parent, di, lp, 1);
-      } while (parent->tw.loose_pages);
-      parent->tw.loose_count = 0;
-#if MDBX_ENABLE_REFUND
-      parent->tw.loose_refund_wl = 0;
-#endif /* MDBX_ENABLE_REFUND */
-      mdbx_tassert(parent, mdbx_dirtylist_check(parent));
-    }
-
-    mdbx_dpl_sort(parent->tw.dirtylist);
-    if (parent->tw.spill_pages)
-      mdbx_spill_purge(parent);
-
-    mdbx_tassert(txn, MDBX_PNL_ALLOCLEN(txn->tw.reclaimed_pglist) >=
-                          MDBX_PNL_SIZE(parent->tw.reclaimed_pglist));
-    memcpy(txn->tw.reclaimed_pglist, parent->tw.reclaimed_pglist,
-           MDBX_PNL_SIZEOF(parent->tw.reclaimed_pglist));
-    mdbx_assert(env, mdbx_pnl_check4assert(
-                         txn->tw.reclaimed_pglist,
-                         (txn->mt_next_pgno /* LY: intentional assignment here,
-                                                   only for assertion */
-                          = parent->mt_next_pgno) -
-                             MDBX_ENABLE_REFUND));
-
-    txn->tw.last_reclaimed = parent->tw.last_reclaimed;
-    if (parent->tw.lifo_reclaimed) {
-      txn->tw.lifo_reclaimed = parent->tw.lifo_reclaimed;
-      parent->tw.lifo_reclaimed =
-          (void *)(intptr_t)MDBX_PNL_SIZE(parent->tw.lifo_reclaimed);
-    }
-
-    txn->tw.retired_pages = parent->tw.retired_pages;
-    parent->tw.retired_pages =
-        (void *)(intptr_t)MDBX_PNL_SIZE(parent->tw.retired_pages);
-
-    txn->mt_txnid = parent->mt_txnid;
-    txn->mt_geo = parent->mt_geo;
-#if MDBX_ENABLE_REFUND
-    txn->tw.loose_refund_wl = 0;
-#endif /* MDBX_ENABLE_REFUND */
-    txn->mt_canary = parent->mt_canary;
-    parent->mt_flags |= MDBX_TXN_HAS_CHILD;
-    parent->mt_child = txn;
-    txn->mt_parent = parent;
-    txn->mt_numdbs = parent->mt_numdbs;
-    txn->mt_owner = parent->mt_owner;
-    memcpy(txn->mt_dbs, parent->mt_dbs, txn->mt_numdbs * sizeof(MDBX_db));
-    /* Copy parent's mt_dbistate, but clear DB_NEW */
-    for (unsigned i = 0; i < txn->mt_numdbs; i++)
-      txn->mt_dbistate[i] =
-          parent->mt_dbistate[i] & ~(DBI_FRESH | DBI_CREAT | DBI_DIRTY);
-    mdbx_tassert(parent,
-                 parent->mt_parent ||
-                     parent->tw.dirtyroom + parent->tw.dirtylist->length ==
-                         env->me_options.dp_limit);
-    assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-    env->me_txn = txn;
-    rc = mdbx_cursor_shadow(parent, txn);
-    if (unlikely(rc != MDBX_SUCCESS))
-      mdbx_txn_end(txn, MDBX_END_FAIL_BEGINCHILD);
-  } else { /* MDBX_TXN_RDONLY */
-    txn->mt_dbiseqs = env->me_dbiseqs;
-  renew:
-    rc = mdbx_txn_renew0(txn, flags);
-  }
-
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (txn != env->me_txn0)
-      mdbx_free(txn);
-  } else {
-    if (flags & (MDBX_TXN_RDONLY_PREPARE - MDBX_TXN_RDONLY))
-      mdbx_assert(env, txn->mt_flags == (MDBX_TXN_RDONLY | MDBX_TXN_FINISHED));
-    else if (flags & MDBX_TXN_RDONLY)
-      mdbx_assert(env, (txn->mt_flags &
-                        ~(MDBX_NOTLS | MDBX_TXN_RDONLY | MDBX_WRITEMAP |
-                          /* Win32: SRWL flag */ MDBX_SHRINK_ALLOWED)) == 0);
-    else {
-      mdbx_assert(env, (txn->mt_flags & ~(MDBX_WRITEMAP | MDBX_SHRINK_ALLOWED |
-                                          MDBX_NOMETASYNC | MDBX_SAFE_NOSYNC |
-                                          MDBX_TXN_SPILLS)) == 0);
-      assert(!txn->tw.spill_pages && !txn->tw.spill_least_removed);
-    }
-    txn->mt_signature = MDBX_MT_SIGNATURE;
-    txn->mt_userctx = context;
-    *ret = txn;
-    mdbx_debug("begin txn %" PRIaTXN "%c %p on env %p, root page %" PRIaPGNO
-               "/%" PRIaPGNO,
-               txn->mt_txnid, (flags & MDBX_TXN_RDONLY) ? 'r' : 'w',
-               (void *)txn, (void *)env, txn->mt_dbs[MAIN_DBI].md_root,
-               txn->mt_dbs[FREE_DBI].md_root);
-  }
-
-  return rc;
-}
-
-int mdbx_txn_info(const MDBX_txn *txn, MDBX_txn_info *info, bool scan_rlt) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED - MDBX_TXN_HAS_CHILD);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!info))
-    return MDBX_EINVAL;
-
-  MDBX_env *const env = txn->mt_env;
-#if MDBX_ENV_CHECKPID
-  if (unlikely(env->me_pid != mdbx_getpid())) {
-    env->me_flags |= MDBX_FATAL_ERROR;
-    return MDBX_PANIC;
-  }
-#endif /* MDBX_ENV_CHECKPID */
-
-  info->txn_id = txn->mt_txnid;
-  info->txn_space_used = pgno2bytes(env, txn->mt_geo.next);
-
-  if (txn->mt_flags & MDBX_TXN_RDONLY) {
-    const MDBX_meta *head_meta;
-    txnid_t head_txnid;
-    uint64_t head_retired;
-    do {
-      /* fetch info from volatile head */
-      head_meta = mdbx_meta_head(env);
-      head_txnid = mdbx_meta_txnid_fluid(env, head_meta);
-      head_retired = unaligned_peek_u64(4, head_meta->mm_pages_retired);
-      info->txn_space_limit_soft = pgno2bytes(env, head_meta->mm_geo.now);
-      info->txn_space_limit_hard = pgno2bytes(env, head_meta->mm_geo.upper);
-      info->txn_space_leftover =
-          pgno2bytes(env, head_meta->mm_geo.now - head_meta->mm_geo.next);
-      mdbx_compiler_barrier();
-    } while (unlikely(head_meta != mdbx_meta_head(env) ||
-                      head_txnid != mdbx_meta_txnid_fluid(env, head_meta)));
-
-    info->txn_reader_lag = head_txnid - info->txn_id;
-    info->txn_space_dirty = info->txn_space_retired = 0;
-    uint64_t reader_snapshot_pages_retired;
-    if (txn->to.reader &&
-        head_retired >
-            (reader_snapshot_pages_retired = atomic_load64(
-                 &txn->to.reader->mr_snapshot_pages_retired, mo_Relaxed))) {
-      info->txn_space_dirty = info->txn_space_retired = pgno2bytes(
-          env, (pgno_t)(head_retired - reader_snapshot_pages_retired));
-
-      size_t retired_next_reader = 0;
-      MDBX_lockinfo *const lck = env->me_lck;
-      if (scan_rlt && info->txn_reader_lag > 1 && lck) {
-        /* find next more recent reader */
-        txnid_t next_reader = head_txnid;
-        const unsigned snap_nreaders =
-            atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-        for (unsigned i = 0; i < snap_nreaders; ++i) {
-        retry:
-          if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease)) {
-            mdbx_jitter4testing(true);
-            const txnid_t snap_txnid =
-                safe64_read(&lck->mti_readers[i].mr_txnid);
-            const uint64_t snap_retired =
-                atomic_load64(&lck->mti_readers[i].mr_snapshot_pages_retired,
-                              mo_AcquireRelease);
-            if (unlikely(snap_retired !=
-                         atomic_load64(
-                             &lck->mti_readers[i].mr_snapshot_pages_retired,
-                             mo_Relaxed)) ||
-                snap_txnid != safe64_read(&lck->mti_readers[i].mr_txnid))
-              goto retry;
-            if (snap_txnid <= txn->mt_txnid) {
-              retired_next_reader = 0;
-              break;
-            }
-            if (snap_txnid < next_reader) {
-              next_reader = snap_txnid;
-              retired_next_reader = pgno2bytes(
-                  env, (pgno_t)(snap_retired -
-                                atomic_load64(
-                                    &txn->to.reader->mr_snapshot_pages_retired,
-                                    mo_Relaxed)));
-            }
-          }
-        }
-      }
-      info->txn_space_dirty = retired_next_reader;
-    }
-  } else {
-    info->txn_space_limit_soft = pgno2bytes(env, txn->mt_geo.now);
-    info->txn_space_limit_hard = pgno2bytes(env, txn->mt_geo.upper);
-    info->txn_space_retired = pgno2bytes(
-        env, txn->mt_child ? (unsigned)(uintptr_t)txn->tw.retired_pages
-                           : MDBX_PNL_SIZE(txn->tw.retired_pages));
-    info->txn_space_leftover = pgno2bytes(env, txn->tw.dirtyroom);
-    info->txn_space_dirty =
-        pgno2bytes(env, txn->mt_env->me_options.dp_limit - txn->tw.dirtyroom);
-    info->txn_reader_lag = INT64_MAX;
-    MDBX_lockinfo *const lck = env->me_lck;
-    if (scan_rlt && lck) {
-      txnid_t oldest_snapshot = txn->mt_txnid;
-      const unsigned snap_nreaders =
-          atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-      if (snap_nreaders) {
-        oldest_snapshot = mdbx_find_oldest(txn);
-        if (oldest_snapshot == txn->mt_txnid - 1) {
-          /* check if there is at least one reader */
-          bool exists = false;
-          for (unsigned i = 0; i < snap_nreaders; ++i) {
-            if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_Relaxed) &&
-                txn->mt_txnid > safe64_read(&lck->mti_readers[i].mr_txnid)) {
-              exists = true;
-              break;
-            }
-          }
-          oldest_snapshot += !exists;
-        }
-      }
-      info->txn_reader_lag = txn->mt_txnid - oldest_snapshot;
-    }
-  }
-
-  return MDBX_SUCCESS;
-}
-
-MDBX_env *mdbx_txn_env(const MDBX_txn *txn) {
-  if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE ||
-               txn->mt_env->me_signature.weak != MDBX_ME_SIGNATURE))
-    return NULL;
-  return txn->mt_env;
-}
-
-uint64_t mdbx_txn_id(const MDBX_txn *txn) {
-  if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
-    return 0;
-  return txn->mt_txnid;
-}
-
-int mdbx_txn_flags(const MDBX_txn *txn) {
-  if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
-    return -1;
-  return txn->mt_flags;
-}
-
-/* Check for misused dbi handles */
-#define TXN_DBI_CHANGED(txn, dbi)                                              \
-  ((txn)->mt_dbiseqs[dbi] != (txn)->mt_env->me_dbiseqs[dbi])
-
-static void dbi_import_locked(MDBX_txn *txn) {
-  MDBX_env *const env = txn->mt_env;
-  const unsigned n = env->me_numdbs;
-  for (unsigned i = CORE_DBS; i < n; ++i) {
-    if (i >= txn->mt_numdbs) {
-      txn->mt_dbistate[i] = 0;
-      if (!(txn->mt_flags & MDBX_TXN_RDONLY))
-        txn->tw.cursors[i] = NULL;
-    }
-    if ((env->me_dbflags[i] & DB_VALID) &&
-        !(txn->mt_dbistate[i] & DBI_USRVALID)) {
-      txn->mt_dbiseqs[i] = env->me_dbiseqs[i];
-      txn->mt_dbs[i].md_flags = env->me_dbflags[i] & DB_PERSISTENT_FLAGS;
-      txn->mt_dbistate[i] = DBI_VALID | DBI_USRVALID | DBI_STALE;
-      mdbx_tassert(txn, txn->mt_dbxs[i].md_cmp != NULL);
-    }
-  }
-  txn->mt_numdbs = n;
-}
-
-/* Import DBI which opened after txn started into context */
-static __cold bool dbi_import(MDBX_txn *txn, MDBX_dbi dbi) {
-  if (dbi < CORE_DBS || dbi >= txn->mt_env->me_numdbs)
-    return false;
-
-  mdbx_ensure(txn->mt_env, mdbx_fastmutex_acquire(&txn->mt_env->me_dbi_lock) ==
-                               MDBX_SUCCESS);
-  dbi_import_locked(txn);
-  mdbx_ensure(txn->mt_env, mdbx_fastmutex_release(&txn->mt_env->me_dbi_lock) ==
-                               MDBX_SUCCESS);
-  return txn->mt_dbistate[dbi] & DBI_USRVALID;
-}
-
-/* Export or close DBI handles opened in this txn. */
-static void dbi_update(MDBX_txn *txn, int keep) {
-  mdbx_tassert(txn, !txn->mt_parent && txn == txn->mt_env->me_txn0);
-  MDBX_dbi n = txn->mt_numdbs;
-  if (n) {
-    bool locked = false;
-    MDBX_env *const env = txn->mt_env;
-
-    for (unsigned i = n; --i >= CORE_DBS;) {
-      if (likely((txn->mt_dbistate[i] & DBI_CREAT) == 0))
-        continue;
-      if (!locked) {
-        mdbx_ensure(env,
-                    mdbx_fastmutex_acquire(&env->me_dbi_lock) == MDBX_SUCCESS);
-        locked = true;
-      }
-      if (env->me_numdbs <= i || txn->mt_dbiseqs[i] != env->me_dbiseqs[i])
-        continue /* dbi explicitly closed and/or then re-opened by other txn */;
-      if (keep) {
-        env->me_dbflags[i] = txn->mt_dbs[i].md_flags | DB_VALID;
-      } else {
-        char *ptr = env->me_dbxs[i].md_name.iov_base;
-        if (ptr) {
-          env->me_dbxs[i].md_name.iov_len = 0;
-          mdbx_memory_fence(false, true);
-          mdbx_assert(env, env->me_dbflags[i] == 0);
-          env->me_dbiseqs[i]++;
-          env->me_dbxs[i].md_name.iov_base = NULL;
-          mdbx_free(ptr);
-        }
-      }
-    }
-
-    n = env->me_numdbs;
-    if (n > CORE_DBS && unlikely(!(env->me_dbflags[n - 1] & DB_VALID))) {
-      if (!locked) {
-        mdbx_ensure(env,
-                    mdbx_fastmutex_acquire(&env->me_dbi_lock) == MDBX_SUCCESS);
-        locked = true;
-      }
-
-      n = env->me_numdbs;
-      while (n > CORE_DBS && !(env->me_dbflags[n - 1] & DB_VALID))
-        --n;
-      env->me_numdbs = n;
-    }
-
-    if (unlikely(locked))
-      mdbx_ensure(env,
-                  mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
-  }
-}
-
-/* Filter-out pgno list from transaction's dirty-page list */
-static void mdbx_dpl_sift(MDBX_txn *const txn, MDBX_PNL pl,
-                          const bool spilled) {
-  if (MDBX_PNL_SIZE(pl) && txn->tw.dirtylist->length) {
-    mdbx_tassert(txn, mdbx_pnl_check4assert(pl, txn->mt_next_pgno << spilled));
-    MDBX_dpl *dl = mdbx_dpl_sort(txn->tw.dirtylist);
-
-    /* Scanning in ascend order */
-    const int step = MDBX_PNL_ASCENDING ? 1 : -1;
-    const int begin = MDBX_PNL_ASCENDING ? 1 : MDBX_PNL_SIZE(pl);
-    const int end = MDBX_PNL_ASCENDING ? MDBX_PNL_SIZE(pl) + 1 : 0;
-    mdbx_tassert(txn, pl[begin] <= pl[end - step]);
-
-    unsigned r = mdbx_dpl_search(dl, pl[begin] >> spilled);
-    mdbx_tassert(txn, dl->sorted == dl->length);
-    for (int i = begin; r <= dl->length;) { /* scan loop */
-      assert(i != end);
-      mdbx_tassert(txn, !spilled || (pl[i] & 1) == 0);
-      pgno_t pl_pgno = pl[i] >> spilled;
-      pgno_t dp_pgno = dl->items[r].pgno;
-      if (likely(dp_pgno != pl_pgno)) {
-        const bool cmp = dp_pgno < pl_pgno;
-        r += cmp;
-        i += cmp ? 0 : step;
-        if (likely(i != end))
-          continue;
-        return;
-      }
-
-      /* update loop */
-      unsigned w = r;
-    remove_dl:
-      if ((txn->mt_env->me_flags & MDBX_WRITEMAP) == 0) {
-        MDBX_page *dp = dl->items[r].ptr;
-        mdbx_dpage_free(txn->mt_env, dp, IS_OVERFLOW(dp) ? dp->mp_pages : 1);
-      }
-      ++r;
-    next_i:
-      i += step;
-      if (unlikely(i == end)) {
-        while (r <= dl->length)
-          dl->items[w++] = dl->items[r++];
-      } else {
-        while (r <= dl->length) {
-          assert(i != end);
-          mdbx_tassert(txn, !spilled || (pl[i] & 1) == 0);
-          pl_pgno = pl[i] >> spilled;
-          dp_pgno = dl->items[r].pgno;
-          if (dp_pgno < pl_pgno)
-            dl->items[w++] = dl->items[r++];
-          else if (dp_pgno > pl_pgno)
-            goto next_i;
-          else
-            goto remove_dl;
-        }
-      }
-      dl->sorted = dl->length = w - 1;
-      txn->tw.dirtyroom += r - w;
-      assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-      return;
-    }
-  }
-}
-
-/* End a transaction, except successful commit of a nested transaction.
- * May be called twice for readonly txns: First reset it, then abort.
- * [in] txn   the transaction handle to end
- * [in] mode  why and how to end the transaction */
-static int mdbx_txn_end(MDBX_txn *txn, const unsigned mode) {
-  MDBX_env *env = txn->mt_env;
-  static const char *const names[] = MDBX_END_NAMES;
-
-#if MDBX_ENV_CHECKPID
-  if (unlikely(txn->mt_env->me_pid != mdbx_getpid())) {
-    env->me_flags |= MDBX_FATAL_ERROR;
-    return MDBX_PANIC;
-  }
-#endif /* MDBX_ENV_CHECKPID */
-
-  mdbx_debug("%s txn %" PRIaTXN "%c %p on mdbenv %p, root page %" PRIaPGNO
-             "/%" PRIaPGNO,
-             names[mode & MDBX_END_OPMASK], txn->mt_txnid,
-             (txn->mt_flags & MDBX_TXN_RDONLY) ? 'r' : 'w', (void *)txn,
-             (void *)env, txn->mt_dbs[MAIN_DBI].md_root,
-             txn->mt_dbs[FREE_DBI].md_root);
-
-  mdbx_ensure(env, txn->mt_txnid >=
-                       /* paranoia is appropriate here */ env->me_oldest->weak);
-
-  int rc = MDBX_SUCCESS;
-  if (F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)) {
-    if (txn->to.reader) {
-      MDBX_reader *slot = txn->to.reader;
-      mdbx_assert(env, slot->mr_pid.weak == env->me_pid);
-      if (likely(!F_ISSET(txn->mt_flags, MDBX_TXN_FINISHED))) {
-        mdbx_assert(env, txn->mt_txnid == slot->mr_txnid.weak &&
-                             slot->mr_txnid.weak >=
-                                 env->me_lck->mti_oldest_reader.weak);
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-        mdbx_txn_valgrind(env, nullptr);
-#endif
-        atomic_store32(&slot->mr_snapshot_pages_used, 0, mo_Relaxed);
-        safe64_reset(&slot->mr_txnid, false);
-        atomic_store32(&env->me_lck->mti_readers_refresh_flag, true,
-                       mo_AcquireRelease);
-      } else {
-        mdbx_assert(env, slot->mr_pid.weak == env->me_pid);
-        mdbx_assert(env, slot->mr_txnid.weak >= SAFE64_INVALID_THRESHOLD);
-      }
-      if (mode & MDBX_END_SLOT) {
-        if ((env->me_flags & MDBX_ENV_TXKEY) == 0)
-          atomic_store32(&slot->mr_pid, 0, mo_AcquireRelease);
-        txn->to.reader = NULL;
-      }
-    }
-#if defined(_WIN32) || defined(_WIN64)
-    if (txn->mt_flags & MDBX_SHRINK_ALLOWED)
-      mdbx_srwlock_ReleaseShared(&env->me_remap_guard);
-#endif
-    txn->mt_numdbs = 0; /* prevent further DBI activity */
-    txn->mt_flags = MDBX_TXN_RDONLY | MDBX_TXN_FINISHED;
-    txn->mt_owner = 0;
-  } else if (!F_ISSET(txn->mt_flags, MDBX_TXN_FINISHED)) {
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-    if (txn == env->me_txn0)
-      mdbx_txn_valgrind(env, nullptr);
-#endif
-    if (!(mode & MDBX_END_EOTDONE)) /* !(already closed cursors) */
-      mdbx_cursors_eot(txn, false);
-
-    txn->mt_flags = MDBX_TXN_FINISHED;
-    txn->mt_owner = 0;
-    env->me_txn = txn->mt_parent;
-    mdbx_pnl_free(txn->tw.spill_pages);
-    txn->tw.spill_pages = nullptr;
-    if (txn == env->me_txn0) {
-      mdbx_assert(env, txn->mt_parent == NULL);
-      /* Export or close DBI handles created in this txn */
-      dbi_update(txn, mode & MDBX_END_UPDATE);
-      mdbx_pnl_shrink(&txn->tw.retired_pages);
-      mdbx_pnl_shrink(&txn->tw.reclaimed_pglist);
-      if (!(env->me_flags & MDBX_WRITEMAP))
-        mdbx_dlist_free(txn);
-      /* The writer mutex was locked in mdbx_txn_begin. */
-      mdbx_txn_unlock(env);
-    } else {
-      mdbx_assert(env, txn->mt_parent != NULL);
-      MDBX_txn *const parent = txn->mt_parent;
-      mdbx_assert(env, parent->mt_signature == MDBX_MT_SIGNATURE);
-      mdbx_assert(env, parent->mt_child == txn &&
-                           (parent->mt_flags & MDBX_TXN_HAS_CHILD) != 0);
-      mdbx_assert(
-          env, mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                     txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-
-      if (txn->tw.lifo_reclaimed) {
-        mdbx_assert(env, MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) >=
-                             (unsigned)(uintptr_t)parent->tw.lifo_reclaimed);
-        MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) =
-            (unsigned)(uintptr_t)parent->tw.lifo_reclaimed;
-        parent->tw.lifo_reclaimed = txn->tw.lifo_reclaimed;
-      }
-
-      if (txn->tw.retired_pages) {
-        mdbx_assert(env, MDBX_PNL_SIZE(txn->tw.retired_pages) >=
-                             (unsigned)(uintptr_t)parent->tw.retired_pages);
-        MDBX_PNL_SIZE(txn->tw.retired_pages) =
-            (unsigned)(uintptr_t)parent->tw.retired_pages;
-        parent->tw.retired_pages = txn->tw.retired_pages;
-      }
-
-      parent->mt_child = nullptr;
-      parent->mt_flags &= ~MDBX_TXN_HAS_CHILD;
-      mdbx_tassert(parent, mdbx_dirtylist_check(parent));
-      mdbx_tassert(parent, mdbx_audit_ex(parent, 0, false) == 0);
-      if (!(env->me_flags & MDBX_WRITEMAP))
-        mdbx_dlist_free(txn);
-      mdbx_dpl_free(txn);
-      mdbx_pnl_free(txn->tw.reclaimed_pglist);
-
-      if (parent->mt_geo.upper != txn->mt_geo.upper ||
-          parent->mt_geo.now != txn->mt_geo.now) {
-        /* undo resize performed by child txn */
-        rc = mdbx_mapresize_implicit(env, parent->mt_next_pgno,
-                                     parent->mt_geo.now, parent->mt_geo.upper);
-        if (rc == MDBX_RESULT_TRUE) {
-          /* unable undo resize (it is regular for Windows),
-           * therefore promote size changes from child to the parent txn */
-          mdbx_warning("unable undo resize performed by child txn, promote to "
-                       "the parent (%u->%u, %u->%u)",
-                       txn->mt_geo.now, parent->mt_geo.now, txn->mt_geo.upper,
-                       parent->mt_geo.upper);
-          parent->mt_geo.now = txn->mt_geo.now;
-          parent->mt_geo.upper = txn->mt_geo.upper;
-          rc = MDBX_SUCCESS;
-        } else if (unlikely(rc != MDBX_SUCCESS)) {
-          mdbx_error("error %d while undo resize performed by child txn, fail "
-                     "the parent",
-                     rc);
-          parent->mt_flags |= MDBX_TXN_ERROR;
-          if (!env->me_dxb_mmap.address)
-            env->me_flags |= MDBX_FATAL_ERROR;
-        }
-      }
-    }
-  }
-
-  mdbx_assert(env, txn == env->me_txn0 || txn->mt_owner == 0);
-  if ((mode & MDBX_END_FREE) != 0 && txn != env->me_txn0) {
-    txn->mt_signature = 0;
-    mdbx_free(txn);
-  }
-
-  return rc;
-}
-
-int mdbx_txn_reset(MDBX_txn *txn) {
-  int rc = check_txn(txn, 0);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  /* This call is only valid for read-only txns */
-  if (unlikely((txn->mt_flags & MDBX_TXN_RDONLY) == 0))
-    return MDBX_EINVAL;
-
-  /* LY: don't close DBI-handles */
-  rc = mdbx_txn_end(txn, MDBX_END_RESET | MDBX_END_UPDATE);
-  if (rc == MDBX_SUCCESS) {
-    mdbx_tassert(txn, txn->mt_signature == MDBX_MT_SIGNATURE);
-    mdbx_tassert(txn, txn->mt_owner == 0);
-  }
-  return rc;
-}
-
-int mdbx_txn_break(MDBX_txn *txn) {
-  do {
-    int rc = check_txn(txn, 0);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    txn->mt_flags |= MDBX_TXN_ERROR;
-    if (txn->mt_flags & MDBX_TXN_RDONLY)
-      break;
-    txn = txn->mt_child;
-  } while (txn);
-  return MDBX_SUCCESS;
-}
-
-int mdbx_txn_abort(MDBX_txn *txn) {
-  int rc = check_txn(txn, 0);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY))
-    /* LY: don't close DBI-handles */
-    return mdbx_txn_end(txn, MDBX_END_ABORT | MDBX_END_UPDATE | MDBX_END_SLOT |
-                                 MDBX_END_FREE);
-
-  if (txn->mt_child)
-    mdbx_txn_abort(txn->mt_child);
-
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  return mdbx_txn_end(txn, MDBX_END_ABORT | MDBX_END_SLOT | MDBX_END_FREE);
-}
-
-/* Count all the pages in each DB and in the freelist and make sure
- * it matches the actual number of pages being used.
- * All named DBs must be open for a correct count. */
-static __cold int mdbx_audit_ex(MDBX_txn *txn, unsigned retired_stored,
-                                bool dont_filter_gc) {
-  pgno_t pending = 0;
-  if ((txn->mt_flags & MDBX_TXN_RDONLY) == 0) {
-    pending = txn->tw.loose_count + MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) +
-              (MDBX_PNL_SIZE(txn->tw.retired_pages) - retired_stored);
-  }
-
-  MDBX_cursor_couple cx;
-  int rc = mdbx_cursor_init(&cx.outer, txn, FREE_DBI);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  pgno_t freecount = 0;
-  MDBX_val key, data;
-  while ((rc = mdbx_cursor_get(&cx.outer, &key, &data, MDBX_NEXT)) == 0) {
-    if (!dont_filter_gc) {
-      if (unlikely(key.iov_len != sizeof(txnid_t)))
-        return MDBX_CORRUPTED;
-      txnid_t id = unaligned_peek_u64(4, key.iov_base);
-      if (txn->tw.lifo_reclaimed) {
-        for (unsigned i = 1; i <= MDBX_PNL_SIZE(txn->tw.lifo_reclaimed); ++i)
-          if (id == txn->tw.lifo_reclaimed[i])
-            goto skip;
-      } else if (id <= txn->tw.last_reclaimed)
-        goto skip;
-    }
-
-    freecount += *(pgno_t *)data.iov_base;
-  skip:;
-  }
-  mdbx_tassert(txn, rc == MDBX_NOTFOUND);
-
-  for (MDBX_dbi i = FREE_DBI; i < txn->mt_numdbs; i++)
-    txn->mt_dbistate[i] &= ~DBI_AUDITED;
-
-  pgno_t count = 0;
-  for (MDBX_dbi i = FREE_DBI; i <= MAIN_DBI; i++) {
-    if (!(txn->mt_dbistate[i] & DBI_VALID))
-      continue;
-    rc = mdbx_cursor_init(&cx.outer, txn, i);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    txn->mt_dbistate[i] |= DBI_AUDITED;
-    if (txn->mt_dbs[i].md_root == P_INVALID)
-      continue;
-    count += txn->mt_dbs[i].md_branch_pages + txn->mt_dbs[i].md_leaf_pages +
-             txn->mt_dbs[i].md_overflow_pages;
-
-    if (i != MAIN_DBI)
-      continue;
-    rc = mdbx_page_search(&cx.outer, NULL, MDBX_PS_FIRST);
-    while (rc == MDBX_SUCCESS) {
-      MDBX_page *mp = cx.outer.mc_pg[cx.outer.mc_top];
-      for (unsigned j = 0; j < page_numkeys(mp); j++) {
-        MDBX_node *node = page_node(mp, j);
-        if (node_flags(node) == F_SUBDATA) {
-          if (unlikely(node_ds(node) != sizeof(MDBX_db)))
-            return MDBX_CORRUPTED;
-          MDBX_db db_copy, *db;
-          memcpy(db = &db_copy, node_data(node), sizeof(db_copy));
-          if ((txn->mt_flags & MDBX_TXN_RDONLY) == 0) {
-            for (MDBX_dbi k = txn->mt_numdbs; --k > MAIN_DBI;) {
-              if ((txn->mt_dbistate[k] & DBI_VALID) &&
-                  /* txn->mt_dbxs[k].md_name.iov_len > 0 && */
-                  node_ks(node) == txn->mt_dbxs[k].md_name.iov_len &&
-                  memcmp(node_key(node), txn->mt_dbxs[k].md_name.iov_base,
-                         node_ks(node)) == 0) {
-                txn->mt_dbistate[k] |= DBI_AUDITED;
-                if (!(txn->mt_dbistate[k] & MDBX_DBI_STALE))
-                  db = txn->mt_dbs + k;
-                break;
-              }
-            }
-          }
-          count +=
-              db->md_branch_pages + db->md_leaf_pages + db->md_overflow_pages;
-        }
-      }
-      rc = mdbx_cursor_sibling(&cx.outer, SIBLING_RIGHT);
-    }
-    mdbx_tassert(txn, rc == MDBX_NOTFOUND);
-  }
-
-  for (MDBX_dbi i = FREE_DBI; i < txn->mt_numdbs; i++) {
-    if ((txn->mt_dbistate[i] & (DBI_VALID | DBI_AUDITED | DBI_STALE)) !=
-        DBI_VALID)
-      continue;
-    for (MDBX_txn *t = txn; t; t = t->mt_parent)
-      if (F_ISSET(t->mt_dbistate[i], DBI_DIRTY | DBI_CREAT)) {
-        count += t->mt_dbs[i].md_branch_pages + t->mt_dbs[i].md_leaf_pages +
-                 t->mt_dbs[i].md_overflow_pages;
-        txn->mt_dbistate[i] |= DBI_AUDITED;
-        break;
-      }
-    if (!(txn->mt_dbistate[i] & DBI_AUDITED)) {
-      mdbx_warning("audit %s@%" PRIaTXN
-                   ": unable account dbi %d / \"%*s\", state 0x%02x",
-                   txn->mt_parent ? "nested-" : "", txn->mt_txnid, i,
-                   (int)txn->mt_dbxs[i].md_name.iov_len,
-                   (const char *)txn->mt_dbxs[i].md_name.iov_base,
-                   txn->mt_dbistate[i]);
-    }
-  }
-
-  if (pending + freecount + count + NUM_METAS == txn->mt_next_pgno)
-    return MDBX_SUCCESS;
-
-  if ((txn->mt_flags & MDBX_TXN_RDONLY) == 0)
-    mdbx_error("audit @%" PRIaTXN ": %u(pending) = %u(loose-count) + "
-               "%u(reclaimed-list) + %u(retired-pending) - %u(retired-stored)",
-               txn->mt_txnid, pending, txn->tw.loose_count,
-               MDBX_PNL_SIZE(txn->tw.reclaimed_pglist),
-               txn->tw.retired_pages ? MDBX_PNL_SIZE(txn->tw.retired_pages) : 0,
-               retired_stored);
-  mdbx_error("audit @%" PRIaTXN ": %" PRIaPGNO "(pending) + %" PRIaPGNO
-             "(free) + %" PRIaPGNO "(count) = %" PRIaPGNO
-             "(total) <> %" PRIaPGNO "(next-pgno)",
-             txn->mt_txnid, pending, freecount, count + NUM_METAS,
-             pending + freecount + count + NUM_METAS, txn->mt_next_pgno);
-  return MDBX_PROBLEM;
-}
-
-static __always_inline unsigned backlog_size(MDBX_txn *txn) {
-  return MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) + txn->tw.loose_count;
-}
-
-/* LY: Prepare a backlog of pages to modify GC itself,
- * while reclaiming is prohibited. It should be enough to prevent search
- * in mdbx_page_alloc() during a deleting, when GC tree is unbalanced. */
-static int mdbx_prep_backlog(MDBX_txn *txn, MDBX_cursor *gc_cursor,
-                             const size_t pnl_bytes) {
-  const unsigned linear4list = number_of_ovpages(txn->mt_env, pnl_bytes);
-  const unsigned backlog4cow = txn->mt_dbs[FREE_DBI].md_depth;
-  const unsigned backlog4rebalance = backlog4cow + 1;
-
-  if (likely(linear4list == 1 &&
-             backlog_size(txn) > (pnl_bytes
-                                      ? backlog4rebalance
-                                      : (backlog4cow + backlog4rebalance))))
-    return MDBX_SUCCESS;
-
-  mdbx_trace(">> pnl_bytes %zu, backlog %u, 4list %u, 4cow %u, 4rebalance %u",
-             pnl_bytes, backlog_size(txn), linear4list, backlog4cow,
-             backlog4rebalance);
-
-  gc_cursor->mc_flags &= ~C_RECLAIMING;
-  int err = mdbx_cursor_touch(gc_cursor);
-  mdbx_trace("== after-touch, backlog %u, err %d", backlog_size(txn), err);
-
-  if (linear4list > 1 && err == MDBX_SUCCESS) {
-    err = mdbx_page_alloc(gc_cursor, linear4list, nullptr,
-                          MDBX_ALLOC_GC | MDBX_ALLOC_CACHE);
-    mdbx_trace("== after-4linear, backlog %u, err %d", backlog_size(txn), err);
-  }
-
-  while (backlog_size(txn) < backlog4cow + linear4list && err == MDBX_SUCCESS)
-    err = mdbx_page_alloc(gc_cursor, 1, NULL, MDBX_ALLOC_GC);
-
-  gc_cursor->mc_flags |= C_RECLAIMING;
-  mdbx_trace("<< backlog %u, err %d", backlog_size(txn), err);
-  return (err != MDBX_NOTFOUND) ? err : MDBX_SUCCESS;
-}
-
-static __inline void clean_reserved_gc_pnl(MDBX_env *env, MDBX_val pnl) {
-  /* PNL is initially empty, zero out at least the length */
-  memset(pnl.iov_base, 0, sizeof(pgno_t));
-  if ((env->me_flags & (MDBX_WRITEMAP | MDBX_NOMEMINIT)) == 0)
-    /* zero out to avoid leaking values from uninitialized malloc'ed memory
-     * to the file in non-writemap mode if length of the saving page-list
-     * was changed during space reservation. */
-    memset(pnl.iov_base, 0, pnl.iov_len);
-}
-
-/* Cleanup reclaimed GC records, than save the retired-list as of this
- * transaction to GC (aka freeDB). This recursive changes the reclaimed-list
- * loose-list and retired-list. Keep trying until it stabilizes. */
-static int mdbx_update_gc(MDBX_txn *txn) {
-  /* txn->tw.reclaimed_pglist[] can grow and shrink during this call.
-   * txn->tw.last_reclaimed and txn->tw.retired_pages[] can only grow.
-   * Page numbers cannot disappear from txn->tw.retired_pages[]. */
-  MDBX_env *const env = txn->mt_env;
-  const bool lifo = (env->me_flags & MDBX_LIFORECLAIM) != 0;
-  const char *dbg_prefix_mode = lifo ? "    lifo" : "    fifo";
-  (void)dbg_prefix_mode;
-  mdbx_trace("\n>>> @%" PRIaTXN, txn->mt_txnid);
-
-  unsigned retired_stored = 0, loop = 0;
-  MDBX_cursor_couple couple;
-  int rc = mdbx_cursor_init(&couple.outer, txn, FREE_DBI);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto bailout_notracking;
-
-  couple.outer.mc_flags |= C_RECLAIMING;
-  couple.outer.mc_next = txn->tw.cursors[FREE_DBI];
-  txn->tw.cursors[FREE_DBI] = &couple.outer;
-
-retry:
-  ++loop;
-retry_noaccount:
-  mdbx_trace("%s", " >> restart");
-  mdbx_tassert(txn,
-               mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                     txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  mdbx_tassert(txn, txn->tw.dirtyroom + txn->tw.dirtylist->length ==
-                        txn->mt_env->me_options.dp_limit);
-  if (unlikely(/* paranoia */ loop > ((MDBX_DEBUG > 0) ? 9 : 99))) {
-    mdbx_error("too more loops %u, bailout", loop);
-    rc = MDBX_PROBLEM;
-    goto bailout;
-  }
-
-  rc = mdbx_prep_backlog(txn, &couple.outer,
-                         MDBX_PNL_SIZEOF(txn->tw.retired_pages));
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto bailout;
-
-  unsigned settled = 0, cleaned_gc_slot = 0, reused_gc_slot = 0,
-           filled_gc_slot = ~0u;
-  txnid_t cleaned_gc_id = 0, gc_rid = txn->tw.last_reclaimed;
-  while (true) {
-    /* Come back here after each Put() in case retired-list changed */
-    MDBX_val key, data;
-    mdbx_trace("%s", " >> continue");
-
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-    if (lifo) {
-      if (cleaned_gc_slot < (txn->tw.lifo_reclaimed
-                                 ? MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)
-                                 : 0)) {
-        settled = 0;
-        cleaned_gc_slot = 0;
-        reused_gc_slot = 0;
-        filled_gc_slot = ~0u;
-        /* LY: cleanup reclaimed records. */
-        do {
-          cleaned_gc_id = txn->tw.lifo_reclaimed[++cleaned_gc_slot];
-          mdbx_tassert(txn, cleaned_gc_slot > 0 &&
-                                cleaned_gc_id < env->me_oldest->weak);
-          key.iov_base = &cleaned_gc_id;
-          key.iov_len = sizeof(cleaned_gc_id);
-          rc = mdbx_cursor_get(&couple.outer, &key, NULL, MDBX_SET);
-          if (rc == MDBX_NOTFOUND)
-            continue;
-          if (unlikely(rc != MDBX_SUCCESS))
-            goto bailout;
-          rc = mdbx_prep_backlog(txn, &couple.outer, 0);
-          if (unlikely(rc != MDBX_SUCCESS))
-            goto bailout;
-          mdbx_tassert(txn, cleaned_gc_id < env->me_oldest->weak);
-          mdbx_trace("%s.cleanup-reclaimed-id [%u]%" PRIaTXN, dbg_prefix_mode,
-                     cleaned_gc_slot, cleaned_gc_id);
-          rc = mdbx_cursor_del(&couple.outer, 0);
-          if (unlikely(rc != MDBX_SUCCESS))
-            goto bailout;
-        } while (cleaned_gc_slot < MDBX_PNL_SIZE(txn->tw.lifo_reclaimed));
-        mdbx_txl_sort(txn->tw.lifo_reclaimed);
-      }
-    } else {
-      /* If using records from GC which we have not yet deleted,
-       * now delete them and any we reserved for tw.reclaimed_pglist. */
-      while (cleaned_gc_id <= txn->tw.last_reclaimed) {
-        gc_rid = cleaned_gc_id;
-        settled = 0;
-        rc = mdbx_cursor_first(&couple.outer, &key, NULL);
-        if (unlikely(rc != MDBX_SUCCESS)) {
-          if (rc == MDBX_NOTFOUND)
-            break;
-          goto bailout;
-        }
-        if (unlikely(key.iov_len != sizeof(txnid_t))) {
-          rc = MDBX_CORRUPTED;
-          goto bailout;
-        }
-        cleaned_gc_id = unaligned_peek_u64(4, key.iov_base);
-        if (unlikely(cleaned_gc_id < MIN_TXNID || cleaned_gc_id > MAX_TXNID)) {
-          rc = MDBX_CORRUPTED;
-          goto bailout;
-        }
-        if (cleaned_gc_id > txn->tw.last_reclaimed)
-          break;
-        if (cleaned_gc_id < txn->tw.last_reclaimed) {
-          rc = mdbx_prep_backlog(txn, &couple.outer, 0);
-          if (unlikely(rc != MDBX_SUCCESS))
-            goto bailout;
-        }
-        mdbx_tassert(txn, cleaned_gc_id <= txn->tw.last_reclaimed);
-        mdbx_tassert(txn, cleaned_gc_id < env->me_oldest->weak);
-        mdbx_trace("%s.cleanup-reclaimed-id %" PRIaTXN, dbg_prefix_mode,
-                   cleaned_gc_id);
-        rc = mdbx_cursor_del(&couple.outer, 0);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      }
-    }
-
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-    mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-    mdbx_tassert(txn, txn->tw.dirtyroom + txn->tw.dirtylist->length ==
-                          txn->mt_env->me_options.dp_limit);
-    if (mdbx_audit_enabled()) {
-      rc = mdbx_audit_ex(txn, retired_stored, false);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto bailout;
-    }
-
-    /* return suitable into unallocated space */
-    if (mdbx_refund(txn)) {
-      mdbx_tassert(
-          txn, mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                     txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-      if (mdbx_audit_enabled()) {
-        rc = mdbx_audit_ex(txn, retired_stored, false);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      }
-    }
-
-    /* handle loose pages - put ones into the reclaimed- or retired-list */
-    if (txn->tw.loose_pages) {
-      /* Return loose page numbers to tw.reclaimed_pglist,
-       * though usually none are left at this point.
-       * The pages themselves remain in dirtylist. */
-      if (unlikely(!txn->tw.lifo_reclaimed && txn->tw.last_reclaimed < 1)) {
-        if (txn->tw.loose_count > 0) {
-          /* Put loose page numbers in tw.retired_pages,
-           * since unable to return them to tw.reclaimed_pglist. */
-          if (unlikely((rc = mdbx_pnl_need(&txn->tw.retired_pages,
-                                           txn->tw.loose_count)) != 0))
-            goto bailout;
-          for (MDBX_page *mp = txn->tw.loose_pages; mp; mp = mp->mp_next)
-            mdbx_pnl_xappend(txn->tw.retired_pages, mp->mp_pgno);
-          mdbx_trace("%s: append %u loose-pages to retired-pages",
-                     dbg_prefix_mode, txn->tw.loose_count);
-        }
-      } else {
-        /* Room for loose pages + temp PNL with same */
-        rc = mdbx_pnl_need(&txn->tw.reclaimed_pglist,
-                           2 * txn->tw.loose_count + 2);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-        MDBX_PNL loose = txn->tw.reclaimed_pglist +
-                         MDBX_PNL_ALLOCLEN(txn->tw.reclaimed_pglist) -
-                         txn->tw.loose_count - 1;
-        unsigned count = 0;
-        for (MDBX_page *mp = txn->tw.loose_pages; mp; mp = mp->mp_next) {
-          mdbx_tassert(txn, mp->mp_flags == (P_LOOSE | P_DIRTY));
-          loose[++count] = mp->mp_pgno;
-        }
-        mdbx_tassert(txn, count == txn->tw.loose_count);
-        MDBX_PNL_SIZE(loose) = count;
-        mdbx_pnl_sort(loose);
-        mdbx_pnl_xmerge(txn->tw.reclaimed_pglist, loose);
-        mdbx_trace("%s: append %u loose-pages to reclaimed-pages",
-                   dbg_prefix_mode, txn->tw.loose_count);
-      }
-
-      /* filter-out list of dirty-pages from loose-pages */
-      MDBX_dpl *const dl = txn->tw.dirtylist;
-      unsigned w = 0;
-      for (unsigned r = w; ++r <= dl->length;) {
-        MDBX_page *dp = dl->items[r].ptr;
-        mdbx_tassert(txn, (dp->mp_flags & P_DIRTY));
-        mdbx_tassert(txn,
-                     dl->items[r].pgno + (IS_OVERFLOW(dp) ? dp->mp_pages : 1) <=
-                         txn->mt_next_pgno);
-        if ((dp->mp_flags & P_LOOSE) == 0) {
-          if (++w != r)
-            dl->items[w] = dl->items[r];
-        } else {
-          mdbx_tassert(txn, dp->mp_flags == (P_LOOSE | P_DIRTY));
-          if ((env->me_flags & MDBX_WRITEMAP) == 0)
-            mdbx_dpage_free(env, dp, 1);
-        }
-      }
-      mdbx_trace("%s: filtered-out loose-pages from %u -> %u dirty-pages",
-                 dbg_prefix_mode, dl->length, w);
-      mdbx_tassert(txn, txn->tw.loose_count == dl->length - w);
-      dl->length = w;
-      dl->sorted = 0;
-      txn->tw.dirtyroom += txn->tw.loose_count;
-      assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-      txn->tw.loose_pages = NULL;
-      txn->tw.loose_count = 0;
-#if MDBX_ENABLE_REFUND
-      txn->tw.loose_refund_wl = 0;
-#endif /* MDBX_ENABLE_REFUND */
-    }
-
-    const unsigned amount = (unsigned)MDBX_PNL_SIZE(txn->tw.reclaimed_pglist);
-    /* handle retired-list - store ones into single gc-record */
-    if (retired_stored < MDBX_PNL_SIZE(txn->tw.retired_pages)) {
-      if (unlikely(!retired_stored)) {
-        /* Make sure last page of GC is touched and on retired-list */
-        couple.outer.mc_flags &= ~C_RECLAIMING;
-        rc = mdbx_page_search(&couple.outer, NULL,
-                              MDBX_PS_LAST | MDBX_PS_MODIFY);
-        couple.outer.mc_flags |= C_RECLAIMING;
-        if (unlikely(rc != MDBX_SUCCESS) && rc != MDBX_NOTFOUND)
-          goto bailout;
-      }
-      /* Write to last page of GC */
-      key.iov_len = sizeof(txn->mt_txnid);
-      key.iov_base = &txn->mt_txnid;
-      do {
-        data.iov_len = MDBX_PNL_SIZEOF(txn->tw.retired_pages);
-        mdbx_prep_backlog(txn, &couple.outer, data.iov_len);
-        rc = mdbx_cursor_put(&couple.outer, &key, &data, MDBX_RESERVE);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-        /* Retry if tw.retired_pages[] grew during the Put() */
-      } while (data.iov_len < MDBX_PNL_SIZEOF(txn->tw.retired_pages));
-
-      retired_stored = (unsigned)MDBX_PNL_SIZE(txn->tw.retired_pages);
-      mdbx_pnl_sort(txn->tw.retired_pages);
-      mdbx_assert(env, data.iov_len == MDBX_PNL_SIZEOF(txn->tw.retired_pages));
-      memcpy(data.iov_base, txn->tw.retired_pages, data.iov_len);
-
-      mdbx_trace("%s.put-retired #%u @ %" PRIaTXN, dbg_prefix_mode,
-                 retired_stored, txn->mt_txnid);
-
-      if (mdbx_log_enabled(MDBX_LOG_EXTRA)) {
-        unsigned i = retired_stored;
-        mdbx_debug_extra("PNL write txn %" PRIaTXN " root %" PRIaPGNO
-                         " num %u, PNL",
-                         txn->mt_txnid, txn->mt_dbs[FREE_DBI].md_root, i);
-        for (; i; i--)
-          mdbx_debug_extra_print(" %" PRIaPGNO, txn->tw.retired_pages[i]);
-        mdbx_debug_extra_print("%s\n", ".");
-      }
-      if (unlikely(amount != MDBX_PNL_SIZE(txn->tw.reclaimed_pglist))) {
-        mdbx_trace("%s.reclaimed-list changed %u -> %u, retry", dbg_prefix_mode,
-                   amount, (unsigned)MDBX_PNL_SIZE(txn->tw.reclaimed_pglist));
-        goto retry_noaccount /* rare case, but avoids GC fragmentation and one
-                                cycle. */
-            ;
-      }
-      continue;
-    }
-
-    /* handle reclaimed and lost pages - merge and store both into gc */
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-    mdbx_tassert(txn, txn->tw.loose_count == 0);
-
-    mdbx_trace("%s", " >> reserving");
-    if (mdbx_audit_enabled()) {
-      rc = mdbx_audit_ex(txn, retired_stored, false);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto bailout;
-    }
-    const unsigned left = amount - settled;
-    mdbx_trace("%s: amount %u, settled %d, left %d, lifo-reclaimed-slots %u, "
-               "reused-gc-slots %u",
-               dbg_prefix_mode, amount, settled, (int)left,
-               txn->tw.lifo_reclaimed
-                   ? (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)
-                   : 0,
-               reused_gc_slot);
-    if (0 >= (int)left)
-      break;
-
-    const unsigned prefer_max_scatter = 257;
-    txnid_t reservation_gc_id;
-    if (lifo) {
-      if (txn->tw.lifo_reclaimed == nullptr) {
-        txn->tw.lifo_reclaimed = mdbx_txl_alloc();
-        if (unlikely(!txn->tw.lifo_reclaimed)) {
-          rc = MDBX_ENOMEM;
-          goto bailout;
-        }
-      }
-      if ((unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) <
-              prefer_max_scatter &&
-          left > ((unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) -
-                  reused_gc_slot) *
-                     env->me_maxgc_ov1page) {
-
-        /* LY: need just a txn-id for save page list. */
-        bool need_cleanup = false;
-        txnid_t snap_oldest;
-      retry_rid:
-        couple.outer.mc_flags &= ~C_RECLAIMING;
-        do {
-          snap_oldest = mdbx_find_oldest(txn);
-          rc = mdbx_page_alloc(&couple.outer, 0, NULL, MDBX_ALLOC_GC);
-          if (likely(rc == MDBX_SUCCESS)) {
-            mdbx_trace("%s: took @%" PRIaTXN " from GC", dbg_prefix_mode,
-                       MDBX_PNL_LAST(txn->tw.lifo_reclaimed));
-            need_cleanup = true;
-          }
-        } while (rc == MDBX_SUCCESS &&
-                 (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) <
-                     prefer_max_scatter &&
-                 left > ((unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) -
-                         reused_gc_slot) *
-                            env->me_maxgc_ov1page);
-        couple.outer.mc_flags |= C_RECLAIMING;
-
-        if (likely(rc == MDBX_SUCCESS)) {
-          mdbx_trace("%s: got enough from GC.", dbg_prefix_mode);
-          continue;
-        } else if (unlikely(rc != MDBX_NOTFOUND))
-          /* LY: some troubles... */
-          goto bailout;
-
-        if (MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)) {
-          if (need_cleanup) {
-            mdbx_txl_sort(txn->tw.lifo_reclaimed);
-            cleaned_gc_slot = 0;
-          }
-          gc_rid = MDBX_PNL_LAST(txn->tw.lifo_reclaimed);
-        } else {
-          mdbx_tassert(txn, txn->tw.last_reclaimed == 0);
-          if (unlikely(mdbx_find_oldest(txn) != snap_oldest))
-            /* should retry mdbx_page_alloc(MDBX_ALLOC_GC)
-             * if the oldest reader changes since the last attempt */
-            goto retry_rid;
-          /* no reclaimable GC entries,
-           * therefore no entries with ID < mdbx_find_oldest(txn) */
-          txn->tw.last_reclaimed = gc_rid = snap_oldest - 1;
-          mdbx_trace("%s: none recycled yet, set rid to @%" PRIaTXN,
-                     dbg_prefix_mode, gc_rid);
-        }
-
-        /* LY: GC is empty, will look any free txn-id in high2low order. */
-        while (MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) < prefer_max_scatter &&
-               left > ((unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) -
-                       reused_gc_slot) *
-                          env->me_maxgc_ov1page) {
-          if (unlikely(gc_rid < 2)) {
-            if (unlikely(MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) <=
-                         reused_gc_slot)) {
-              mdbx_notice("** restart: reserve depleted (reused_gc_slot %u >= "
-                          "lifo_reclaimed %u" PRIaTXN,
-                          reused_gc_slot,
-                          (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed));
-              goto retry;
-            }
-            break;
-          }
-
-          mdbx_tassert(txn, gc_rid >= MIN_TXNID && gc_rid <= MAX_TXNID);
-          --gc_rid;
-          key.iov_base = &gc_rid;
-          key.iov_len = sizeof(gc_rid);
-          rc = mdbx_cursor_get(&couple.outer, &key, &data, MDBX_SET_KEY);
-          if (unlikely(rc == MDBX_SUCCESS)) {
-            mdbx_debug("%s: GC's id %" PRIaTXN
-                       " is used, continue bottom-up search",
-                       dbg_prefix_mode, gc_rid);
-            ++gc_rid;
-            rc = mdbx_cursor_get(&couple.outer, &key, &data, MDBX_FIRST);
-            if (rc == MDBX_NOTFOUND) {
-              mdbx_debug("%s: GC is empty", dbg_prefix_mode);
-              break;
-            }
-            if (unlikely(rc != MDBX_SUCCESS ||
-                         key.iov_len != sizeof(mdbx_tid_t))) {
-              rc = MDBX_CORRUPTED;
-              goto bailout;
-            }
-            txnid_t gc_first = unaligned_peek_u64(4, key.iov_base);
-            if (unlikely(gc_first < MIN_TXNID || gc_first > MAX_TXNID)) {
-              rc = MDBX_CORRUPTED;
-              goto bailout;
-            }
-            if (gc_first < 2) {
-              mdbx_debug("%s: no free GC's id(s) less than %" PRIaTXN,
-                         dbg_prefix_mode, gc_rid);
-              break;
-            }
-            gc_rid = gc_first - 1;
-          }
-
-          rc = mdbx_txl_append(&txn->tw.lifo_reclaimed, gc_rid);
-          if (unlikely(rc != MDBX_SUCCESS))
-            goto bailout;
-
-          if (reused_gc_slot)
-            /* rare case, but it is better to clear and re-create GC entries
-             * with less fragmentation. */
-            need_cleanup = true;
-          else
-            cleaned_gc_slot +=
-                1 /* mark cleanup is not needed for added slot. */;
-
-          mdbx_trace("%s: append @%" PRIaTXN
-                     " to lifo-reclaimed, cleaned-gc-slot = %u",
-                     dbg_prefix_mode, gc_rid, cleaned_gc_slot);
-        }
-
-        if (need_cleanup) {
-          cleaned_gc_slot = 0;
-          mdbx_trace("%s: restart inner-loop to clear and re-create GC entries",
-                     dbg_prefix_mode);
-          continue;
-        }
-      }
-
-      const unsigned i =
-          (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) - reused_gc_slot;
-      mdbx_tassert(txn, i > 0 && i <= MDBX_PNL_SIZE(txn->tw.lifo_reclaimed));
-      reservation_gc_id = txn->tw.lifo_reclaimed[i];
-      mdbx_trace("%s: take @%" PRIaTXN " from lifo-reclaimed[%u]",
-                 dbg_prefix_mode, reservation_gc_id, i);
-    } else {
-      mdbx_tassert(txn, txn->tw.lifo_reclaimed == NULL);
-      if (unlikely(gc_rid == 0)) {
-        gc_rid = mdbx_find_oldest(txn) - 1;
-        rc = mdbx_cursor_get(&couple.outer, &key, NULL, MDBX_FIRST);
-        if (rc == MDBX_SUCCESS) {
-          if (unlikely(key.iov_len != sizeof(txnid_t))) {
-            rc = MDBX_CORRUPTED;
-            goto bailout;
-          }
-          txnid_t gc_first = unaligned_peek_u64(4, key.iov_base);
-          if (unlikely(gc_first < MIN_TXNID || gc_first > MAX_TXNID)) {
-            rc = MDBX_CORRUPTED;
-            goto bailout;
-          }
-          if (gc_rid >= gc_first)
-            gc_rid = gc_first - 1;
-          if (unlikely(gc_rid == 0)) {
-            mdbx_error("%s", "** no GC tail-space to store");
-            goto retry;
-          }
-        } else if (rc != MDBX_NOTFOUND)
-          goto bailout;
-        txn->tw.last_reclaimed = gc_rid;
-      }
-      reservation_gc_id = gc_rid--;
-      mdbx_trace("%s: take @%" PRIaTXN " from head-gc-id", dbg_prefix_mode,
-                 reservation_gc_id);
-    }
-    ++reused_gc_slot;
-
-    unsigned chunk = left;
-    if (unlikely(chunk > env->me_maxgc_ov1page)) {
-      const unsigned avail_gc_slots =
-          txn->tw.lifo_reclaimed
-              ? (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) -
-                    reused_gc_slot + 1
-              : (gc_rid < INT16_MAX) ? (unsigned)gc_rid : INT16_MAX;
-      if (avail_gc_slots > 1) {
-        if (chunk < env->me_maxgc_ov1page * 2)
-          chunk /= 2;
-        else {
-          const unsigned threshold =
-              env->me_maxgc_ov1page * ((avail_gc_slots < prefer_max_scatter)
-                                           ? avail_gc_slots
-                                           : prefer_max_scatter);
-          if (left < threshold)
-            chunk = env->me_maxgc_ov1page;
-          else {
-            const unsigned tail = left - threshold + env->me_maxgc_ov1page + 1;
-            unsigned span = 1;
-            unsigned avail = (unsigned)((pgno2bytes(env, span) - PAGEHDRSZ) /
-                                        sizeof(pgno_t)) /*- 1 + span */;
-            if (tail > avail) {
-              for (unsigned i = amount - span; i > 0; --i) {
-                if (MDBX_PNL_ASCENDING
-                        ? (txn->tw.reclaimed_pglist[i] + span)
-                        : (txn->tw.reclaimed_pglist[i] - span) ==
-                              txn->tw.reclaimed_pglist[i + span]) {
-                  span += 1;
-                  avail = (unsigned)((pgno2bytes(env, span) - PAGEHDRSZ) /
-                                     sizeof(pgno_t)) -
-                          1 + span;
-                  if (avail >= tail)
-                    break;
-                }
-              }
-            }
-
-            chunk = (avail >= tail) ? tail - span
-                                    : (avail_gc_slots > 3 &&
-                                       reused_gc_slot < prefer_max_scatter - 3)
-                                          ? avail - span
-                                          : tail;
-          }
-        }
-      }
-    }
-    mdbx_tassert(txn, chunk > 0);
-
-    mdbx_trace("%s: gc_rid %" PRIaTXN ", reused_gc_slot %u, reservation-id "
-               "%" PRIaTXN,
-               dbg_prefix_mode, gc_rid, reused_gc_slot, reservation_gc_id);
-
-    mdbx_trace("%s: chunk %u, gc-per-ovpage %u", dbg_prefix_mode, chunk,
-               env->me_maxgc_ov1page);
-
-    mdbx_tassert(txn, reservation_gc_id < env->me_oldest->weak);
-    if (unlikely(reservation_gc_id < 1 ||
-                 reservation_gc_id >=
-                     atomic_load64(env->me_oldest, mo_Relaxed))) {
-      mdbx_error("%s", "** internal error (reservation_gc_id)");
-      rc = MDBX_PROBLEM;
-      goto bailout;
-    }
-
-    key.iov_len = sizeof(reservation_gc_id);
-    key.iov_base = &reservation_gc_id;
-    data.iov_len = (chunk + 1) * sizeof(pgno_t);
-    mdbx_trace("%s.reserve: %u [%u...%u] @%" PRIaTXN, dbg_prefix_mode, chunk,
-               settled + 1, settled + chunk + 1, reservation_gc_id);
-    mdbx_prep_backlog(txn, &couple.outer, data.iov_len);
-    rc = mdbx_cursor_put(&couple.outer, &key, &data,
-                         MDBX_RESERVE | MDBX_NOOVERWRITE);
-    mdbx_tassert(txn,
-                 mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                       txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto bailout;
-
-    clean_reserved_gc_pnl(env, data);
-    settled += chunk;
-    mdbx_trace("%s.settled %u (+%u), continue", dbg_prefix_mode, settled,
-               chunk);
-
-    if (txn->tw.lifo_reclaimed &&
-        unlikely(amount < MDBX_PNL_SIZE(txn->tw.reclaimed_pglist))) {
-      mdbx_notice("** restart: reclaimed-list growth %u -> %u", amount,
-                  (unsigned)MDBX_PNL_SIZE(txn->tw.reclaimed_pglist));
-      goto retry_noaccount;
-    }
-
-    continue;
-  }
-
-  mdbx_tassert(
-      txn,
-      cleaned_gc_slot ==
-          (txn->tw.lifo_reclaimed ? MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) : 0));
-
-  mdbx_trace("%s", " >> filling");
-  /* Fill in the reserved records */
-  filled_gc_slot =
-      txn->tw.lifo_reclaimed
-          ? (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed) - reused_gc_slot
-          : reused_gc_slot;
-  rc = MDBX_SUCCESS;
-  mdbx_tassert(txn,
-               mdbx_pnl_check4assert(txn->tw.reclaimed_pglist,
-                                     txn->mt_next_pgno - MDBX_ENABLE_REFUND));
-  mdbx_tassert(txn, mdbx_dirtylist_check(txn));
-  if (MDBX_PNL_SIZE(txn->tw.reclaimed_pglist)) {
-    MDBX_val key, data;
-    key.iov_len = data.iov_len = 0; /* avoid MSVC warning */
-    key.iov_base = data.iov_base = NULL;
-
-    const unsigned amount = MDBX_PNL_SIZE(txn->tw.reclaimed_pglist);
-    unsigned left = amount;
-    if (txn->tw.lifo_reclaimed == nullptr) {
-      mdbx_tassert(txn, lifo == 0);
-      rc = mdbx_cursor_first(&couple.outer, &key, &data);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto bailout;
-    } else {
-      mdbx_tassert(txn, lifo != 0);
-    }
-
-    while (true) {
-      txnid_t fill_gc_id;
-      mdbx_trace("%s: left %u of %u", dbg_prefix_mode, left,
-                 (unsigned)MDBX_PNL_SIZE(txn->tw.reclaimed_pglist));
-      if (txn->tw.lifo_reclaimed == nullptr) {
-        mdbx_tassert(txn, lifo == 0);
-        fill_gc_id = unaligned_peek_u64(4, key.iov_base);
-        if (filled_gc_slot-- == 0 || fill_gc_id > txn->tw.last_reclaimed) {
-          mdbx_notice(
-              "** restart: reserve depleted (filled_slot %u, fill_id %" PRIaTXN
-              " > last_reclaimed %" PRIaTXN,
-              filled_gc_slot, fill_gc_id, txn->tw.last_reclaimed);
-          goto retry;
-        }
-      } else {
-        mdbx_tassert(txn, lifo != 0);
-        if (++filled_gc_slot >
-            (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)) {
-          mdbx_notice("** restart: reserve depleted (filled_gc_slot %u > "
-                      "lifo_reclaimed %u" PRIaTXN,
-                      filled_gc_slot,
-                      (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed));
-          goto retry;
-        }
-        fill_gc_id = txn->tw.lifo_reclaimed[filled_gc_slot];
-        mdbx_trace("%s.seek-reservation @%" PRIaTXN " at lifo_reclaimed[%u]",
-                   dbg_prefix_mode, fill_gc_id, filled_gc_slot);
-        key.iov_base = &fill_gc_id;
-        key.iov_len = sizeof(fill_gc_id);
-        rc = mdbx_cursor_get(&couple.outer, &key, &data, MDBX_SET_KEY);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      }
-      mdbx_tassert(txn, cleaned_gc_slot ==
-                            (txn->tw.lifo_reclaimed
-                                 ? MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)
-                                 : 0));
-      mdbx_tassert(txn, fill_gc_id > 0 && fill_gc_id < env->me_oldest->weak);
-      key.iov_base = &fill_gc_id;
-      key.iov_len = sizeof(fill_gc_id);
-
-      mdbx_tassert(txn, data.iov_len >= sizeof(pgno_t) * 2);
-      couple.outer.mc_flags |= C_GCFREEZE;
-      unsigned chunk = (unsigned)(data.iov_len / sizeof(pgno_t)) - 1;
-      if (unlikely(chunk > left)) {
-        mdbx_trace("%s: chunk %u > left %u, @%" PRIaTXN, dbg_prefix_mode, chunk,
-                   left, fill_gc_id);
-        if ((loop < 5 && chunk - left > loop / 2) ||
-            chunk - left > env->me_maxgc_ov1page) {
-          data.iov_len = (left + 1) * sizeof(pgno_t);
-          if (loop < 7)
-            couple.outer.mc_flags &= ~C_GCFREEZE;
-        }
-        chunk = left;
-      }
-      rc = mdbx_cursor_put(&couple.outer, &key, &data,
-                           MDBX_CURRENT | MDBX_RESERVE);
-      couple.outer.mc_flags &= ~C_GCFREEZE;
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto bailout;
-      clean_reserved_gc_pnl(env, data);
-
-      if (unlikely(txn->tw.loose_count ||
-                   amount != MDBX_PNL_SIZE(txn->tw.reclaimed_pglist))) {
-        mdbx_notice("** restart: reclaimed-list growth (%u -> %u, loose +%u)",
-                    amount, MDBX_PNL_SIZE(txn->tw.reclaimed_pglist),
-                    txn->tw.loose_count);
-        goto retry;
-      }
-      if (unlikely(txn->tw.lifo_reclaimed
-                       ? cleaned_gc_slot < MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)
-                       : cleaned_gc_id < txn->tw.last_reclaimed)) {
-        mdbx_notice("%s", "** restart: reclaimed-slots changed");
-        goto retry;
-      }
-      if (unlikely(retired_stored != MDBX_PNL_SIZE(txn->tw.retired_pages))) {
-        mdbx_tassert(txn,
-                     retired_stored < MDBX_PNL_SIZE(txn->tw.retired_pages));
-        mdbx_notice("** restart: retired-list growth (%u -> %u)",
-                    retired_stored, MDBX_PNL_SIZE(txn->tw.retired_pages));
-        goto retry;
-      }
-
-      pgno_t *dst = data.iov_base;
-      *dst++ = chunk;
-      pgno_t *src = MDBX_PNL_BEGIN(txn->tw.reclaimed_pglist) + left - chunk;
-      memcpy(dst, src, chunk * sizeof(pgno_t));
-      pgno_t *from = src, *to = src + chunk;
-      mdbx_trace("%s.fill: %u [ %u:%" PRIaPGNO "...%u:%" PRIaPGNO
-                 "] @%" PRIaTXN,
-                 dbg_prefix_mode, chunk,
-                 (unsigned)(from - txn->tw.reclaimed_pglist), from[0],
-                 (unsigned)(to - txn->tw.reclaimed_pglist), to[-1], fill_gc_id);
-
-      left -= chunk;
-      if (mdbx_audit_enabled()) {
-        rc = mdbx_audit_ex(txn, retired_stored + amount - left, true);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      }
-      if (left == 0) {
-        rc = MDBX_SUCCESS;
-        break;
-      }
-
-      if (txn->tw.lifo_reclaimed == nullptr) {
-        mdbx_tassert(txn, lifo == 0);
-        rc = mdbx_cursor_next(&couple.outer, &key, &data, MDBX_NEXT);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      } else {
-        mdbx_tassert(txn, lifo != 0);
-      }
-    }
-  }
-
-  mdbx_tassert(txn, rc == MDBX_SUCCESS);
-  if (unlikely(txn->tw.loose_count != 0 ||
-               filled_gc_slot !=
-                   (txn->tw.lifo_reclaimed
-                        ? (unsigned)MDBX_PNL_SIZE(txn->tw.lifo_reclaimed)
-                        : 0))) {
-    mdbx_notice("** restart: reserve excess (filled-slot %u, loose-count %u)",
-                filled_gc_slot, txn->tw.loose_count);
-    goto retry;
-  }
-
-  mdbx_tassert(txn,
-               txn->tw.lifo_reclaimed == NULL ||
-                   cleaned_gc_slot == MDBX_PNL_SIZE(txn->tw.lifo_reclaimed));
-
-bailout:
-  txn->tw.cursors[FREE_DBI] = couple.outer.mc_next;
-
-bailout_notracking:
-  MDBX_PNL_SIZE(txn->tw.reclaimed_pglist) = 0;
-  mdbx_trace("<<< %u loops, rc = %d", loop, rc);
-  return rc;
-}
-
-static int mdbx_flush_iov(MDBX_txn *const txn, struct iovec *iov,
-                          unsigned iov_items, size_t iov_off,
-                          size_t iov_bytes) {
-  MDBX_env *const env = txn->mt_env;
-  mdbx_assert(env, iov_items > 0);
-  int rc;
-  if (likely(iov_items == 1)) {
-    mdbx_assert(env, iov->iov_len == iov_bytes);
-    rc = mdbx_pwrite(env->me_lazy_fd, iov->iov_base, iov_bytes, iov_off);
-  } else {
-    rc = mdbx_pwritev(env->me_lazy_fd, iov, iov_items, iov_off, iov_bytes);
-  }
-
-  if (unlikely(rc != MDBX_SUCCESS))
-    mdbx_error("Write error: %s", mdbx_strerror(rc));
-  else {
-    VALGRIND_MAKE_MEM_DEFINED(txn->mt_env->me_map + iov_off, iov_bytes);
-    ASAN_UNPOISON_MEMORY_REGION(txn->mt_env->me_map + iov_off, iov_bytes);
-  }
-
-  for (unsigned i = 0; i < iov_items; i++)
-    mdbx_dpage_free(env, (MDBX_page *)iov[i].iov_base,
-                    bytes2pgno(env, iov[i].iov_len));
-  return rc;
-}
-
-/* Flush (some) dirty pages to the map, after clearing their dirty flag.
- * [in] txn   the transaction that's being committed
- * [in] keep  number of initial pages in dirtylist to keep dirty.
- * Returns 0 on success, non-zero on failure. */
-__hot static int mdbx_page_flush(MDBX_txn *txn, const unsigned keep) {
-  struct iovec iov[MDBX_COMMIT_PAGES];
-  MDBX_dpl *const dl = mdbx_dpl_sort(txn->tw.dirtylist);
-  MDBX_env *const env = txn->mt_env;
-  pgno_t flush_begin = MAX_PAGENO;
-  pgno_t flush_end = MIN_PAGENO;
-  int rc = MDBX_SUCCESS;
-  unsigned iov_items = 0;
-  size_t iov_bytes = 0;
-  size_t iov_off = 0;
-
-  unsigned r, w;
-  for (r = w = keep; ++r <= dl->length;) {
-    MDBX_page *dp = dl->items[r].ptr;
-    mdbx_tassert(txn,
-                 dp->mp_pgno >= MIN_PAGENO && dp->mp_pgno < txn->mt_next_pgno);
-    mdbx_tassert(txn, dp->mp_flags & P_DIRTY);
-
-    /* Don't flush this page yet */
-    if (dp->mp_flags & P_KEEP) {
-      dp->mp_flags -= P_KEEP;
-      dl->items[++w] = dl->items[r];
-      continue;
-    }
-    if (dp->mp_flags & P_LOOSE) {
-      dl->items[++w] = dl->items[r];
-      continue;
-    }
-
-    const unsigned npages = IS_OVERFLOW(dp) ? dp->mp_pages : 1;
-    flush_begin = (flush_begin < dp->mp_pgno) ? flush_begin : dp->mp_pgno;
-    flush_end =
-        (flush_end > dp->mp_pgno + npages) ? flush_end : dp->mp_pgno + npages;
-    env->me_unsynced_pages->weak += npages;
-    dp->mp_flags -= P_DIRTY;
-    dp->mp_txnid = pp_txnid2chk(txn);
-
-    if ((env->me_flags & MDBX_WRITEMAP) == 0) {
-      const size_t size = pgno2bytes(env, npages);
-      if (iov_off + iov_bytes != pgno2bytes(env, dp->mp_pgno) ||
-          iov_items == ARRAY_LENGTH(iov) || iov_bytes + size > MAX_WRITE) {
-        if (iov_items) {
-          rc = mdbx_flush_iov(txn, iov, iov_items, iov_off, iov_bytes);
-#if defined(__linux__) || defined(__gnu_linux__)
-          if (mdbx_linux_kernel_version >= 0x02060b00)
-          /* Linux kernels older than version 2.6.11 ignore the addr and nbytes
-           * arguments, making this function fairly expensive. Therefore, the
-           * whole cache is always flushed. */
-#endif /* Linux */
-            mdbx_flush_incoherent_mmap(env->me_map + iov_off, iov_bytes,
-                                       env->me_os_psize);
-          iov_items = 0;
-          iov_bytes = 0;
-          if (unlikely(rc != MDBX_SUCCESS)) {
-            do
-              dl->items[++w] = dl->items[r];
-            while (++r <= dl->length);
-            break;
-          }
-        }
-        iov_off = pgno2bytes(env, dp->mp_pgno);
-      }
-      iov[iov_items].iov_base = (void *)dp;
-      iov[iov_items].iov_len = size;
-      iov_items += 1;
-      iov_bytes += size;
-    }
-  }
-
-  mdbx_tassert(txn, dl->sorted == dl->length && r == dl->length + 1);
-  txn->tw.dirtyroom += dl->length - w;
-  assert(txn->tw.dirtyroom <= txn->mt_env->me_options.dp_limit);
-  dl->sorted = dl->length = w;
-  mdbx_tassert(txn, txn->mt_parent ||
-                        txn->tw.dirtyroom + txn->tw.dirtylist->length ==
-                            txn->mt_env->me_options.dp_limit);
-
-  if (iov_items)
-    rc = mdbx_flush_iov(txn, iov, iov_items, iov_off, iov_bytes);
-
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    txn->mt_flags |= MDBX_TXN_ERROR;
-    return rc;
-  }
-
-#if defined(__linux__) || defined(__gnu_linux__)
-  if ((env->me_flags & MDBX_WRITEMAP) == 0 &&
-      mdbx_linux_kernel_version < 0x02060b00)
-    /* Linux kernels older than version 2.6.11 ignore the addr and nbytes
-     * arguments, making this function fairly expensive. Therefore, the
-     * whole cache is always flushed. */
-    mdbx_flush_incoherent_mmap(env->me_map + pgno2bytes(env, flush_begin),
-                               pgno2bytes(env, flush_end - flush_begin),
-                               env->me_os_psize);
-#endif /* Linux */
-
-  /* TODO: use flush_begin & flush_end for msync() & sync_file_range(). */
-  (void)flush_begin;
-  (void)flush_end;
-  return MDBX_SUCCESS;
-}
-
-/* Check txn and dbi arguments to a function */
-static __always_inline bool mdbx_txn_dbi_exists(MDBX_txn *txn, MDBX_dbi dbi,
-                                                unsigned validity) {
-  if (likely(dbi < txn->mt_numdbs && (txn->mt_dbistate[dbi] & validity)))
-    return true;
-
-  return dbi_import(txn, dbi);
-}
-
-int mdbx_txn_commit(MDBX_txn *txn) { return __inline_mdbx_txn_commit(txn); }
-
-/* Merge child txn into parent */
-static __inline void mdbx_txn_merge(MDBX_txn *const parent, MDBX_txn *const txn,
-                                    const unsigned parent_retired_len) {
-  MDBX_dpl *const src = mdbx_dpl_sort(txn->tw.dirtylist);
-
-  /* Remove refunded pages from parent's dirty list */
-  MDBX_dpl *const dst = mdbx_dpl_sort(parent->tw.dirtylist);
-  while (MDBX_ENABLE_REFUND && dst->length &&
-         dst->items[dst->length].pgno >= parent->mt_next_pgno) {
-    if (!(txn->mt_env->me_flags & MDBX_WRITEMAP)) {
-      MDBX_page *dp = dst->items[dst->length].ptr;
-      mdbx_dpage_free(txn->mt_env, dp, IS_OVERFLOW(dp) ? dp->mp_pages : 1);
-    }
-    dst->length -= 1;
-  }
-  parent->tw.dirtyroom += dst->sorted - dst->length;
-  assert(parent->tw.dirtyroom <= parent->mt_env->me_options.dp_limit);
-  dst->sorted = dst->length;
-  mdbx_tassert(parent,
-               parent->mt_parent ||
-                   parent->tw.dirtyroom + parent->tw.dirtylist->length ==
-                       parent->mt_env->me_options.dp_limit);
-
-  /* Remove reclaimed pages from parent's dirty list */
-  const MDBX_PNL reclaimed_list = parent->tw.reclaimed_pglist;
-  mdbx_dpl_sift(parent, reclaimed_list, false);
-
-  /* Move retired pages from parent's dirty & spilled list to reclaimed */
-  unsigned r, w, d, s, l;
-  for (r = w = parent_retired_len;
-       ++r <= MDBX_PNL_SIZE(parent->tw.retired_pages);) {
-    const pgno_t pgno = parent->tw.retired_pages[r];
-    const unsigned di = mdbx_dpl_exist(parent->tw.dirtylist, pgno);
-    const unsigned si = (!di && unlikely(parent->tw.spill_pages))
-                            ? mdbx_pnl_exist(parent->tw.spill_pages, pgno << 1)
-                            : 0;
-    unsigned npages;
-    const char *kind;
-    if (di) {
-      MDBX_page *dp = parent->tw.dirtylist->items[di].ptr;
-      mdbx_tassert(parent, (dp->mp_flags & ~(P_LEAF | P_LEAF2 | P_BRANCH |
-                                             P_OVERFLOW | P_DIRTY)) == 0);
-      npages = IS_OVERFLOW(dp) ? dp->mp_pages : 1;
-      mdbx_page_wash(parent, di, dp, npages);
-      kind = "dirty";
-      l = 1;
-      if (unlikely(npages > l)) {
-        /* OVERFLOW-страница могла быть переиспользована по частям. Тогда
-         * в retired-списке может быть только начало последовательности,
-         * а остаток растащен по dirty, spilled и reclaimed спискам. Поэтому
-         * переносим в reclaimed с проверкой на обрыв последовательности.
-         * В любом случае, все осколки будут учтены и отфильтрованы, т.е. если
-         * страница была разбита на части, то важно удалить dirty-элемент,
-         * а все осколки будут учтены отдельно. */
-
-        /* Список retired страниц не сортирован, но для ускорения сортировки
-         * дополняется в соответствии с MDBX_PNL_ASCENDING */
-#if MDBX_PNL_ASCENDING
-        const unsigned len = MDBX_PNL_SIZE(parent->tw.retired_pages);
-        while (r < len && parent->tw.retired_pages[r + 1] == pgno + l) {
-          ++r;
-          if (++l == npages)
-            break;
-        }
-#else
-        while (w > parent_retired_len &&
-               parent->tw.retired_pages[w - 1] == pgno + l) {
-          --w;
-          if (++l == npages)
-            break;
-        }
-#endif
-      }
-    } else if (unlikely(si)) {
-      l = npages = 1;
-      mdbx_spill_remove(parent, si, 1);
-      kind = "spilled";
-    } else {
-      parent->tw.retired_pages[++w] = pgno;
-      continue;
-    }
-
-    mdbx_debug("reclaim retired parent's %u->%u %s page %" PRIaPGNO, npages, l,
-               kind, pgno);
-    int err = mdbx_pnl_insert_range(&parent->tw.reclaimed_pglist, pgno, l);
-    mdbx_ensure(txn->mt_env, err == MDBX_SUCCESS);
-  }
-  MDBX_PNL_SIZE(parent->tw.retired_pages) = w;
-
-  /* Filter-out parent spill list */
-  if (parent->tw.spill_pages && MDBX_PNL_SIZE(parent->tw.spill_pages) > 0) {
-    const MDBX_PNL sl = mdbx_spill_purge(parent);
-    unsigned len = MDBX_PNL_SIZE(sl);
-    if (len) {
-      /* Remove refunded pages from parent's spill list */
-      if (MDBX_ENABLE_REFUND &&
-          MDBX_PNL_MOST(sl) >= (parent->mt_next_pgno << 1)) {
-#if MDBX_PNL_ASCENDING
-        unsigned i = MDBX_PNL_SIZE(sl);
-        assert(MDBX_PNL_MOST(sl) == MDBX_PNL_LAST(sl));
-        do {
-          if ((sl[i] & 1) == 0)
-            mdbx_debug("refund parent's spilled page %" PRIaPGNO, sl[i] >> 1);
-          i -= 1;
-        } while (i && sl[i] >= (parent->mt_next_pgno << 1));
-        MDBX_PNL_SIZE(sl) = i;
-#else
-        assert(MDBX_PNL_MOST(sl) == MDBX_PNL_FIRST(sl));
-        unsigned i = 0;
-        do {
-          ++i;
-          if ((sl[i] & 1) == 0)
-            mdbx_debug("refund parent's spilled page %" PRIaPGNO, sl[i] >> 1);
-        } while (i < len && sl[i + 1] >= (parent->mt_next_pgno << 1));
-        MDBX_PNL_SIZE(sl) = len -= i;
-        memmove(sl + 1, sl + 1 + i, len * sizeof(sl[0]));
-#endif
-      }
-      mdbx_tassert(txn, mdbx_pnl_check4assert(sl, parent->mt_next_pgno << 1));
-
-      /* Remove reclaimed pages from parent's spill list */
-      s = MDBX_PNL_SIZE(sl), r = MDBX_PNL_SIZE(reclaimed_list);
-      /* Scanning from end to begin */
-      while (s && r) {
-        if (sl[s] & 1) {
-          --s;
-          continue;
-        }
-        const pgno_t spilled_pgno = sl[s] >> 1;
-        const pgno_t reclaimed_pgno = reclaimed_list[r];
-        if (reclaimed_pgno != spilled_pgno) {
-          const bool cmp = MDBX_PNL_ORDERED(spilled_pgno, reclaimed_pgno);
-          s -= !cmp;
-          r -= cmp;
-        } else {
-          mdbx_debug("remove reclaimed parent's spilled page %" PRIaPGNO,
-                     reclaimed_pgno);
-          mdbx_spill_remove(parent, s, 1);
-          --s;
-          --r;
-        }
-      }
-
-      /* Remove anything in our dirty list from parent's spill list */
-      /* Scanning spill list in descend order */
-      const int step = MDBX_PNL_ASCENDING ? -1 : 1;
-      s = MDBX_PNL_ASCENDING ? MDBX_PNL_SIZE(sl) : 1;
-      d = src->length;
-      while (d && (MDBX_PNL_ASCENDING ? s > 0 : s <= MDBX_PNL_SIZE(sl))) {
-        if (sl[s] & 1) {
-          s += step;
-          continue;
-        }
-        const pgno_t spilled_pgno = sl[s] >> 1;
-        const pgno_t dirty_pgno_form = src->items[d].pgno;
-        MDBX_page *dp = src->items[d].ptr;
-        const unsigned npages = IS_OVERFLOW(dp) ? dp->mp_pages : 1;
-        const pgno_t dirty_pgno_to = dirty_pgno_form + npages;
-        if (dirty_pgno_form > spilled_pgno) {
-          --d;
-          continue;
-        }
-        if (dirty_pgno_to <= spilled_pgno) {
-          s += step;
-          continue;
-        }
-
-        mdbx_debug("remove dirtied parent's spilled %u page %" PRIaPGNO, npages,
-                   dirty_pgno_form);
-        mdbx_spill_remove(parent, s, 1);
-        s += step;
-      }
-
-      /* Squash deleted pagenums if we deleted any */
-      mdbx_spill_purge(parent);
-    }
-  }
-
-  /* Remove anything in our spill list from parent's dirty list */
-  if (txn->tw.spill_pages) {
-    mdbx_tassert(txn, mdbx_pnl_check4assert(txn->tw.spill_pages,
-                                            parent->mt_next_pgno << 1));
-    mdbx_dpl_sift(parent, txn->tw.spill_pages, true);
-    mdbx_tassert(parent,
-                 parent->mt_parent ||
-                     parent->tw.dirtyroom + parent->tw.dirtylist->length ==
-                         parent->mt_env->me_options.dp_limit);
-  }
-
-  /* Find length of merging our dirty list with parent's and release
-   * filter-out pages */
-  for (l = 0, d = dst->length, s = src->length; d > 0 && s > 0;) {
-    const MDBX_page *sp = src->items[s].ptr;
-    mdbx_tassert(parent,
-                 (sp->mp_flags & ~(P_LEAF | P_LEAF2 | P_BRANCH | P_OVERFLOW |
-                                   P_DIRTY | P_LOOSE)) == 0);
-    const unsigned s_npages = IS_OVERFLOW(sp) ? sp->mp_pages : 1;
-    const pgno_t s_pgno = src->items[s].pgno;
-
-    MDBX_page *dp = dst->items[d].ptr;
-    mdbx_tassert(parent, (dp->mp_flags & ~(P_LEAF | P_LEAF2 | P_BRANCH |
-                                           P_OVERFLOW | P_DIRTY)) == 0);
-    const unsigned d_npages = IS_OVERFLOW(dp) ? dp->mp_pages : 1;
-    const pgno_t d_pgno = dst->items[d].pgno;
-
-    if (d_pgno >= s_pgno + s_npages) {
-      --d;
-      ++l;
-    } else if (d_pgno + d_npages <= s_pgno) {
-      --s;
-      ++l;
-    } else {
-      dst->items[d--].ptr = nullptr;
-      if ((txn->mt_flags & MDBX_WRITEMAP) == 0)
-        mdbx_dpage_free(txn->mt_env, dp, d_npages);
-    }
-  }
-  assert(dst->sorted == dst->length);
-  mdbx_tassert(parent, dst->allocated >= l + d + s);
-  dst->sorted = l + d + s; /* the merged length */
-
-  /* Merge our dirty list into parent's, i.e. merge(dst, src) -> dst */
-  if (dst->sorted >= dst->length) {
-    /* from end to begin with dst extending */
-    for (l = dst->sorted, s = src->length, d = dst->length; s > 0 && d > 0;) {
-      if (unlikely(l <= d)) {
-        /* squash to get a gap of free space for merge */
-        for (r = w = 1; r <= d; ++r)
-          if (dst->items[r].ptr) {
-            if (w != r) {
-              dst->items[w] = dst->items[r];
-              dst->items[r].ptr = nullptr;
-            }
-            ++w;
-          }
-        mdbx_notice("squash to begin for extending-merge %u -> %u", d, w - 1);
-        d = w - 1;
-        continue;
-      }
-      assert(l > d);
-      if (dst->items[d].ptr) {
-        dst->items[l--] = (dst->items[d].pgno > src->items[s].pgno)
-                              ? dst->items[d--]
-                              : src->items[s--];
-      } else
-        --d;
-    }
-    if (s > 0) {
-      assert(l == s);
-      while (d > 0) {
-        assert(dst->items[d].ptr == nullptr);
-        --d;
-      }
-      do {
-        assert(l > 0);
-        dst->items[l--] = src->items[s--];
-      } while (s > 0);
-    } else {
-      assert(l == d);
-      while (l > 0) {
-        assert(dst->items[l].ptr != nullptr);
-        --l;
-      }
-    }
-  } else {
-    /* from begin to end with dst shrinking (a lot of new overflow pages) */
-    for (l = s = d = 1; s <= src->length && d <= dst->length;) {
-      if (unlikely(l >= d)) {
-        /* squash to get a gap of free space for merge */
-        for (r = w = dst->length; r >= d; --r)
-          if (dst->items[r].ptr) {
-            if (w != r) {
-              dst->items[w] = dst->items[r];
-              dst->items[r].ptr = nullptr;
-            }
-            --w;
-          }
-        mdbx_notice("squash to end for shrinking-merge %u -> %u", d, w + 1);
-        d = w + 1;
-        continue;
-      }
-      assert(l < d);
-      if (dst->items[d].ptr) {
-        dst->items[l++] = (dst->items[d].pgno < src->items[s].pgno)
-                              ? dst->items[d++]
-                              : src->items[s++];
-      } else
-        ++d;
-    }
-    if (s <= src->length) {
-      assert(dst->sorted - l == src->length - s);
-      while (d <= dst->length) {
-        assert(dst->items[d].ptr == nullptr);
-        --d;
-      }
-      do {
-        assert(l <= dst->sorted);
-        dst->items[l++] = src->items[s++];
-      } while (s <= src->length);
-    } else {
-      assert(dst->sorted - l == dst->length - d);
-      while (l <= dst->sorted) {
-        assert(l <= d && d <= dst->length && dst->items[d].ptr);
-        dst->items[l++] = dst->items[d++];
-      }
-    }
-  }
-  parent->tw.dirtyroom -= dst->sorted - dst->length;
-  assert(parent->tw.dirtyroom <= parent->mt_env->me_options.dp_limit);
-  dst->length = dst->sorted;
-  mdbx_tassert(parent,
-               parent->mt_parent ||
-                   parent->tw.dirtyroom + parent->tw.dirtylist->length ==
-                       parent->mt_env->me_options.dp_limit);
-  mdbx_tassert(parent, mdbx_dirtylist_check(parent));
-  mdbx_dpl_free(txn);
-
-  if (txn->tw.spill_pages) {
-    if (parent->tw.spill_pages) {
-      /* Must not fail since space was preserved above. */
-      mdbx_pnl_xmerge(parent->tw.spill_pages, txn->tw.spill_pages);
-      mdbx_pnl_free(txn->tw.spill_pages);
-    } else {
-      parent->tw.spill_pages = txn->tw.spill_pages;
-      parent->tw.spill_least_removed = txn->tw.spill_least_removed;
-    }
-    mdbx_tassert(parent, mdbx_dirtylist_check(parent));
-  }
-
-  parent->mt_flags &= ~MDBX_TXN_HAS_CHILD;
-  if (parent->tw.spill_pages) {
-    assert(mdbx_pnl_check4assert(parent->tw.spill_pages,
-                                 parent->mt_next_pgno << 1));
-    if (MDBX_PNL_SIZE(parent->tw.spill_pages))
-      parent->mt_flags |= MDBX_TXN_SPILLS;
-  }
-}
-
-int mdbx_txn_commit_ex(MDBX_txn *txn, MDBX_commit_latency *latency) {
-  STATIC_ASSERT(MDBX_TXN_FINISHED ==
-                MDBX_TXN_BLOCKED - MDBX_TXN_HAS_CHILD - MDBX_TXN_ERROR);
-  const uint64_t ts_0 = latency ? mdbx_osal_monotime() : 0;
-  uint64_t ts_1 = 0, ts_2 = 0, ts_3 = 0, ts_4 = 0;
-  uint32_t audit_duration = 0;
-
-  int rc = check_txn(txn, MDBX_TXN_FINISHED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto provide_latency;
-
-  if (unlikely(txn->mt_flags & MDBX_TXN_ERROR)) {
-    rc = MDBX_RESULT_TRUE;
-    goto fail;
-  }
-
-  MDBX_env *env = txn->mt_env;
-#if MDBX_ENV_CHECKPID
-  if (unlikely(env->me_pid != mdbx_getpid())) {
-    env->me_flags |= MDBX_FATAL_ERROR;
-    rc = MDBX_PANIC;
-    goto provide_latency;
-  }
-#endif /* MDBX_ENV_CHECKPID */
-
-  /* mdbx_txn_end() mode for a commit which writes nothing */
-  unsigned end_mode =
-      MDBX_END_PURE_COMMIT | MDBX_END_UPDATE | MDBX_END_SLOT | MDBX_END_FREE;
-  if (unlikely(F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
-    goto done;
-
-  if (txn->mt_child) {
-    rc = mdbx_txn_commit_ex(txn->mt_child, NULL);
-    mdbx_tassert(txn, txn->mt_child == NULL);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto fail;
-  }
-
-  if (unlikely(txn != env->me_txn)) {
-    mdbx_debug("%s", "attempt to commit unknown transaction");
-    rc = MDBX_EINVAL;
-    goto fail;
-  }
-
-  if (txn->mt_parent) {
-    mdbx_tassert(txn, mdbx_audit_ex(txn, 0, false) == 0);
-    mdbx_assert(env, txn != env->me_txn0);
-    MDBX_txn *const parent = txn->mt_parent;
-    mdbx_assert(env, parent->mt_signature == MDBX_MT_SIGNATURE);
-    mdbx_assert(env, parent->mt_child == txn &&
-                         (parent->mt_flags & MDBX_TXN_HAS_CHILD) != 0);
-    mdbx_assert(env, mdbx_dirtylist_check(txn));
-
-    if (txn->tw.dirtylist->length == 0 && !(txn->mt_flags & MDBX_TXN_DIRTY) &&
-        parent->mt_numdbs == txn->mt_numdbs) {
-      for (int i = txn->mt_numdbs; --i >= 0;) {
-        mdbx_tassert(txn, (txn->mt_dbistate[i] & DBI_DIRTY) == 0);
-        if ((txn->mt_dbistate[i] & DBI_STALE) &&
-            !(parent->mt_dbistate[i] & DBI_STALE))
-          mdbx_tassert(txn, memcmp(&parent->mt_dbs[i], &txn->mt_dbs[i],
-                                   sizeof(MDBX_db)) == 0);
-      }
-
-      mdbx_tassert(txn, memcmp(&parent->mt_geo, &txn->mt_geo,
-                               sizeof(parent->mt_geo)) == 0);
-      mdbx_tassert(txn, memcmp(&parent->mt_canary, &txn->mt_canary,
-                               sizeof(parent->mt_canary)) == 0);
-      mdbx_tassert(txn, !txn->tw.spill_pages ||
-                            MDBX_PNL_SIZE(txn->tw.spill_pages) == 0);
-      mdbx_tassert(txn, txn->tw.loose_count == 0);
-
-      /* fast completion of pure nested transaction */
-      end_mode = MDBX_END_PURE_COMMIT | MDBX_END_SLOT | MDBX_END_FREE;
-      goto done;
-    }
-
-    /* Preserve space for spill list to avoid parent's state corruption
-     * if allocation fails. */
-    const unsigned parent_retired_len =
-        (unsigned)(uintptr_t)parent->tw.retired_pages;
-    mdbx_tassert(txn,
-                 parent_retired_len <= MDBX_PNL_SIZE(txn->tw.retired_pages));
-    const unsigned retired_delta =
-        MDBX_PNL_SIZE(txn->tw.retired_pages) - parent_retired_len;
-    if (retired_delta) {
-      rc = mdbx_pnl_need(&txn->tw.reclaimed_pglist, retired_delta);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto fail;
-    }
-
-    if (txn->tw.spill_pages) {
-      if (parent->tw.spill_pages) {
-        rc = mdbx_pnl_need(&parent->tw.spill_pages,
-                           MDBX_PNL_SIZE(txn->tw.spill_pages));
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto fail;
-      }
-      mdbx_spill_purge(txn);
-    }
-
-    if (unlikely(txn->tw.dirtylist->length + parent->tw.dirtylist->length >
-                     parent->tw.dirtylist->allocated &&
-                 !mdbx_dpl_reserve(parent, txn->tw.dirtylist->length +
-                                               parent->tw.dirtylist->length))) {
-      rc = MDBX_ENOMEM;
-      goto fail;
-    }
-
-    //-------------------------------------------------------------------------
-
-    parent->tw.lifo_reclaimed = txn->tw.lifo_reclaimed;
-    txn->tw.lifo_reclaimed = NULL;
-
-    parent->tw.retired_pages = txn->tw.retired_pages;
-    txn->tw.retired_pages = NULL;
-
-    mdbx_pnl_free(parent->tw.reclaimed_pglist);
-    parent->tw.reclaimed_pglist = txn->tw.reclaimed_pglist;
-    txn->tw.reclaimed_pglist = NULL;
-    parent->tw.last_reclaimed = txn->tw.last_reclaimed;
-
-    parent->mt_geo = txn->mt_geo;
-    parent->mt_canary = txn->mt_canary;
-    parent->mt_flags |= txn->mt_flags & MDBX_TXN_DIRTY;
-
-    /* Move loose pages to parent */
-#if MDBX_ENABLE_REFUND
-    parent->tw.loose_refund_wl = txn->tw.loose_refund_wl;
-#endif /* MDBX_ENABLE_REFUND */
-    parent->tw.loose_count = txn->tw.loose_count;
-    parent->tw.loose_pages = txn->tw.loose_pages;
-
-    /* Merge our cursors into parent's and close them */
-    mdbx_cursors_eot(txn, true);
-    end_mode |= MDBX_END_EOTDONE;
-
-    /* Update parent's DBs array */
-    memcpy(parent->mt_dbs, txn->mt_dbs, txn->mt_numdbs * sizeof(MDBX_db));
-    parent->mt_numdbs = txn->mt_numdbs;
-    parent->mt_dbistate[FREE_DBI] = txn->mt_dbistate[FREE_DBI];
-    parent->mt_dbistate[MAIN_DBI] = txn->mt_dbistate[MAIN_DBI];
-    for (unsigned i = CORE_DBS; i < txn->mt_numdbs; i++) {
-      /* preserve parent's status */
-      const uint8_t state =
-          txn->mt_dbistate[i] |
-          (parent->mt_dbistate[i] & (DBI_CREAT | DBI_FRESH | DBI_DIRTY));
-      mdbx_debug("db %u dbi-state %s 0x%02x -> 0x%02x", i,
-                 (parent->mt_dbistate[i] != state) ? "update" : "still",
-                 parent->mt_dbistate[i], state);
-      parent->mt_dbistate[i] = state;
-    }
-
-    ts_1 = latency ? mdbx_osal_monotime() : 0;
-    mdbx_txn_merge(parent, txn, parent_retired_len);
-    ts_2 = latency ? mdbx_osal_monotime() : 0;
-    env->me_txn = parent;
-    parent->mt_child = NULL;
-    mdbx_tassert(parent, mdbx_dirtylist_check(parent));
-
-#if MDBX_ENABLE_REFUND
-    mdbx_refund(parent);
-    if (mdbx_assert_enabled()) {
-      /* Check parent's loose pages not suitable for refund */
-      for (MDBX_page *lp = parent->tw.loose_pages; lp; lp = lp->mp_next)
-        mdbx_tassert(parent, lp->mp_pgno < parent->tw.loose_refund_wl &&
-                                 lp->mp_pgno + 1 < parent->mt_next_pgno);
-      /* Check parent's reclaimed pages not suitable for refund */
-      if (MDBX_PNL_SIZE(parent->tw.reclaimed_pglist))
-        mdbx_tassert(parent, MDBX_PNL_MOST(parent->tw.reclaimed_pglist) + 1 <
-                                 parent->mt_next_pgno);
-    }
-#endif /* MDBX_ENABLE_REFUND */
-
-    ts_4 = ts_3 = latency ? mdbx_osal_monotime() : 0;
-    txn->mt_signature = 0;
-    mdbx_free(txn);
-    mdbx_tassert(parent, mdbx_audit_ex(parent, 0, false) == 0);
-    rc = MDBX_SUCCESS;
-    goto provide_latency;
-  }
-
-  mdbx_tassert(txn, txn->tw.dirtyroom + txn->tw.dirtylist->length ==
-                        txn->mt_env->me_options.dp_limit);
-  mdbx_cursors_eot(txn, false);
-  end_mode |= MDBX_END_EOTDONE;
-
-  if (txn->tw.dirtylist->length == 0 &&
-      (txn->mt_flags & (MDBX_TXN_DIRTY | MDBX_TXN_SPILLS)) == 0) {
-    for (int i = txn->mt_numdbs; --i >= 0;)
-      mdbx_tassert(txn, (txn->mt_dbistate[i] & DBI_DIRTY) == 0);
-    rc = MDBX_SUCCESS;
-    goto done;
-  }
-
-  mdbx_debug("committing txn %" PRIaTXN " %p on mdbenv %p, root page %" PRIaPGNO
-             "/%" PRIaPGNO,
-             txn->mt_txnid, (void *)txn, (void *)env,
-             txn->mt_dbs[MAIN_DBI].md_root, txn->mt_dbs[FREE_DBI].md_root);
-
-  /* Update DB root pointers */
-  if (txn->mt_numdbs > CORE_DBS) {
-    MDBX_cursor_couple couple;
-    MDBX_val data;
-    data.iov_len = sizeof(MDBX_db);
-
-    rc = mdbx_cursor_init(&couple.outer, txn, MAIN_DBI);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto fail;
-    for (MDBX_dbi i = CORE_DBS; i < txn->mt_numdbs; i++) {
-      if (txn->mt_dbistate[i] & DBI_DIRTY) {
-        if (unlikely(TXN_DBI_CHANGED(txn, i))) {
-          rc = MDBX_BAD_DBI;
-          goto fail;
-        }
-        MDBX_db *db = &txn->mt_dbs[i];
-        mdbx_debug("update main's entry for sub-db %u, mod_txnid %" PRIaTXN
-                   " -> %" PRIaTXN,
-                   i, pp_txnid2chk(txn), db->md_mod_txnid);
-        db->md_mod_txnid = pp_txnid2chk(txn);
-        data.iov_base = db;
-        WITH_CURSOR_TRACKING(couple.outer,
-                             rc = mdbx_cursor_put(&couple.outer,
-                                                  &txn->mt_dbxs[i].md_name,
-                                                  &data, F_SUBDATA));
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto fail;
-      }
-    }
-  }
-
-  ts_1 = latency ? mdbx_osal_monotime() : 0;
-  rc = mdbx_update_gc(txn);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto fail;
-
-  ts_2 = latency ? mdbx_osal_monotime() : 0;
-  if (mdbx_audit_enabled()) {
-    rc = mdbx_audit_ex(txn, MDBX_PNL_SIZE(txn->tw.retired_pages), true);
-    const uint64_t audit_end = mdbx_osal_monotime();
-    audit_duration = mdbx_osal_monotime_to_16dot16(audit_end - ts_2);
-    ts_2 = audit_end;
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto fail;
-  }
-
-  rc = mdbx_page_flush(txn, 0);
-  ts_3 = latency ? mdbx_osal_monotime() : 0;
-  if (likely(rc == MDBX_SUCCESS)) {
-    if (txn->mt_dbs[MAIN_DBI].md_flags & DBI_DIRTY)
-      txn->mt_dbs[MAIN_DBI].md_mod_txnid = pp_txnid2chk(txn);
-
-    MDBX_meta meta, *head = mdbx_meta_head(env);
-    memcpy(meta.mm_magic_and_version, head->mm_magic_and_version, 8);
-    meta.mm_extra_flags = head->mm_extra_flags;
-    meta.mm_validator_id = head->mm_validator_id;
-    meta.mm_extra_pagehdr = head->mm_extra_pagehdr;
-    unaligned_poke_u64(4, meta.mm_pages_retired,
-                       unaligned_peek_u64(4, head->mm_pages_retired) +
-                           MDBX_PNL_SIZE(txn->tw.retired_pages));
-
-    meta.mm_geo = txn->mt_geo;
-    meta.mm_dbs[FREE_DBI] = txn->mt_dbs[FREE_DBI];
-    meta.mm_dbs[MAIN_DBI] = txn->mt_dbs[MAIN_DBI];
-    meta.mm_canary = txn->mt_canary;
-    mdbx_meta_set_txnid(env, &meta, txn->mt_txnid);
-
-    rc = mdbx_sync_locked(
-        env, env->me_flags | txn->mt_flags | MDBX_SHRINK_ALLOWED, &meta);
-  }
-  ts_4 = latency ? mdbx_osal_monotime() : 0;
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    env->me_flags |= MDBX_FATAL_ERROR;
-    goto fail;
-  }
-
-  end_mode = MDBX_END_COMMITTED | MDBX_END_UPDATE | MDBX_END_EOTDONE;
-
-done:
-  rc = mdbx_txn_end(txn, end_mode);
-
-provide_latency:
-  if (latency) {
-    latency->audit = audit_duration;
-    latency->preparation =
-        ts_1 ? mdbx_osal_monotime_to_16dot16(ts_1 - ts_0) : 0;
-    latency->gc =
-        (ts_1 && ts_2) ? mdbx_osal_monotime_to_16dot16(ts_2 - ts_1) : 0;
-    latency->write =
-        (ts_2 && ts_3) ? mdbx_osal_monotime_to_16dot16(ts_3 - ts_2) : 0;
-    latency->sync =
-        (ts_3 && ts_4) ? mdbx_osal_monotime_to_16dot16(ts_4 - ts_3) : 0;
-    const uint64_t ts_5 = mdbx_osal_monotime();
-    latency->ending = ts_4 ? mdbx_osal_monotime_to_16dot16(ts_5 - ts_4) : 0;
-    latency->whole = mdbx_osal_monotime_to_16dot16(ts_5 - ts_0);
-  }
-  return rc;
-
-fail:
-  mdbx_txn_abort(txn);
-  goto provide_latency;
-}
-
-static __cold int
-mdbx_validate_meta(MDBX_env *env, MDBX_meta *const meta, uint64_t *filesize,
-                   const MDBX_page *const page, const unsigned meta_number,
-                   MDBX_meta *dest, const unsigned guess_pagesize) {
-  const uint64_t magic_and_version =
-      unaligned_peek_u64(4, &meta->mm_magic_and_version);
-  if (magic_and_version != MDBX_DATA_MAGIC &&
-      magic_and_version != MDBX_DATA_MAGIC_DEVEL) {
-    mdbx_error("meta[%u] has invalid magic/version %" PRIx64, meta_number,
-               magic_and_version);
-    return ((magic_and_version >> 8) != MDBX_MAGIC) ? MDBX_INVALID
-                                                    : MDBX_VERSION_MISMATCH;
-  }
-
-  if (page->mp_pgno != meta_number) {
-    mdbx_error("meta[%u] has invalid pageno %" PRIaPGNO, meta_number,
-               page->mp_pgno);
-    return MDBX_INVALID;
-  }
-
-  if (page->mp_flags != P_META) {
-    mdbx_error("page #%u not a meta-page", meta_number);
-    return MDBX_INVALID;
-  }
-
-  /* LY: check pagesize */
-  if (!is_powerof2(meta->mm_psize) || meta->mm_psize < MIN_PAGESIZE ||
-      meta->mm_psize > MAX_PAGESIZE) {
-    mdbx_warning("meta[%u] has invalid pagesize (%u), skip it", meta_number,
-                 meta->mm_psize);
-    return is_powerof2(meta->mm_psize) ? MDBX_VERSION_MISMATCH : MDBX_INVALID;
-  }
-
-  if (dest && meta_number == 0 && guess_pagesize != meta->mm_psize) {
-    dest->mm_psize = meta->mm_psize;
-    mdbx_verbose("meta[%u] took pagesize %u", meta_number, meta->mm_psize);
-  }
-
-  if (unaligned_peek_u64(4, &meta->mm_txnid_a) !=
-      unaligned_peek_u64(4, &meta->mm_txnid_b)) {
-    mdbx_warning("meta[%u] not completely updated, skip it", meta_number);
-    return MDBX_RESULT_TRUE;
-  }
-
-  /* LY: check signature as a checksum */
-  if (META_IS_STEADY(meta) &&
-      unaligned_peek_u64(4, &meta->mm_datasync_sign) != mdbx_meta_sign(meta)) {
-    mdbx_warning("meta[%u] has invalid steady-checksum (0x%" PRIx64
-                 " != 0x%" PRIx64 "), skip it",
-                 meta_number, unaligned_peek_u64(4, &meta->mm_datasync_sign),
-                 mdbx_meta_sign(meta));
-    return MDBX_RESULT_TRUE;
-  }
-
-  mdbx_debug("read meta%" PRIaPGNO " = root %" PRIaPGNO "/%" PRIaPGNO
-             ", geo %" PRIaPGNO "/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
-             " +%u -%u, txn_id %" PRIaTXN ", %s",
-             page->mp_pgno, meta->mm_dbs[MAIN_DBI].md_root,
-             meta->mm_dbs[FREE_DBI].md_root, meta->mm_geo.lower,
-             meta->mm_geo.next, meta->mm_geo.now, meta->mm_geo.upper,
-             meta->mm_geo.grow, meta->mm_geo.shrink,
-             unaligned_peek_u64(4, meta->mm_txnid_a), mdbx_durable_str(meta));
-
-  /* LY: check min-pages value */
-  if (meta->mm_geo.lower < MIN_PAGENO || meta->mm_geo.lower > MAX_PAGENO) {
-    mdbx_warning("meta[%u] has invalid min-pages (%" PRIaPGNO "), skip it",
-                 meta_number, meta->mm_geo.lower);
-    return MDBX_INVALID;
-  }
-
-  /* LY: check max-pages value */
-  if (meta->mm_geo.upper < MIN_PAGENO || meta->mm_geo.upper > MAX_PAGENO ||
-      meta->mm_geo.upper < meta->mm_geo.lower) {
-    mdbx_warning("meta[%u] has invalid max-pages (%" PRIaPGNO "), skip it",
-                 meta_number, meta->mm_geo.upper);
-    return MDBX_INVALID;
-  }
-
-  /* LY: check last_pgno */
-  if (meta->mm_geo.next < MIN_PAGENO || meta->mm_geo.next - 1 > MAX_PAGENO) {
-    mdbx_warning("meta[%u] has invalid next-pageno (%" PRIaPGNO "), skip it",
-                 meta_number, meta->mm_geo.next);
-    return MDBX_CORRUPTED;
-  }
-
-  /* LY: check filesize & used_bytes */
-  const uint64_t used_bytes = meta->mm_geo.next * (uint64_t)meta->mm_psize;
-  if (used_bytes > *filesize) {
-    /* Here could be a race with DB-shrinking performed by other process */
-    int err = mdbx_filesize(env->me_lazy_fd, filesize);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-    if (used_bytes > *filesize) {
-      mdbx_warning("meta[%u] used-bytes (%" PRIu64 ") beyond filesize (%" PRIu64
-                   "), skip it",
-                   meta_number, used_bytes, *filesize);
-      return MDBX_CORRUPTED;
-    }
-  }
-  if (meta->mm_geo.next - 1 > MAX_PAGENO || used_bytes > MAX_MAPSIZE) {
-    mdbx_warning("meta[%u] has too large used-space (%" PRIu64 "), skip it",
-                 meta_number, used_bytes);
-    return MDBX_TOO_LARGE;
-  }
-
-  /* LY: check mapsize limits */
-  const uint64_t mapsize_min = meta->mm_geo.lower * (uint64_t)meta->mm_psize;
-  STATIC_ASSERT(MAX_MAPSIZE < PTRDIFF_MAX - MAX_PAGESIZE);
-  STATIC_ASSERT(MIN_MAPSIZE < MAX_MAPSIZE);
-  if (mapsize_min < MIN_MAPSIZE || mapsize_min > MAX_MAPSIZE) {
-    if (MAX_MAPSIZE != MAX_MAPSIZE64 && mapsize_min > MAX_MAPSIZE &&
-        mapsize_min <= MAX_MAPSIZE64) {
-      mdbx_assert(env, meta->mm_geo.next - 1 <= MAX_PAGENO &&
-                           used_bytes <= MAX_MAPSIZE);
-      mdbx_warning("meta[%u] has too large min-mapsize (%" PRIu64 "), "
-                   "but size of used space still acceptable (%" PRIu64 ")",
-                   meta_number, mapsize_min, used_bytes);
-      meta->mm_geo.lower = (pgno_t)(MAX_MAPSIZE / meta->mm_psize);
-    } else {
-      mdbx_warning("meta[%u] has invalid min-mapsize (%" PRIu64 "), skip it",
-                   meta_number, mapsize_min);
-      return MDBX_VERSION_MISMATCH;
-    }
-  }
-
-  const uint64_t mapsize_max = meta->mm_geo.upper * (uint64_t)meta->mm_psize;
-  STATIC_ASSERT(MIN_MAPSIZE < MAX_MAPSIZE);
-  if (mapsize_max > MAX_MAPSIZE ||
-      MAX_PAGENO < ceil_powerof2((size_t)mapsize_max, env->me_os_psize) /
-                       (size_t)meta->mm_psize) {
-    /* allow to open large DB from a 32-bit environment */
-    mdbx_assert(env, meta->mm_geo.next - 1 <= MAX_PAGENO &&
-                         used_bytes <= MAX_MAPSIZE);
-    mdbx_warning("meta[%u] has too large max-mapsize (%" PRIu64 "), "
-                 "but size of used space still acceptable (%" PRIu64 ")",
-                 meta_number, mapsize_max, used_bytes);
-    meta->mm_geo.upper = (pgno_t)(MAX_MAPSIZE / meta->mm_psize);
-  }
-
-  /* LY: check and silently put mm_geo.now into [geo.lower...geo.upper].
-   *
-   * Copy-with-compaction by previous version of libmdbx could produce DB-file
-   * less than meta.geo.lower bound, in case actual filling is low or no data
-   * at all. This is not a problem as there is no damage or loss of data.
-   * Therefore it is better not to consider such situation as an error, but
-   * silently correct it. */
-  if (meta->mm_geo.now < meta->mm_geo.lower)
-    meta->mm_geo.now = meta->mm_geo.lower;
-  if (meta->mm_geo.now > meta->mm_geo.upper &&
-      meta->mm_geo.next <= meta->mm_geo.upper)
-    meta->mm_geo.now = meta->mm_geo.upper;
-
-  if (meta->mm_geo.next > meta->mm_geo.now) {
-    mdbx_warning("meta[%u] next-pageno (%" PRIaPGNO
-                 ") is beyond end-pgno (%" PRIaPGNO "), skip it",
-                 meta_number, meta->mm_geo.next, meta->mm_geo.now);
-    return MDBX_CORRUPTED;
-  }
-
-  /* LY: GC root */
-  if (meta->mm_dbs[FREE_DBI].md_root == P_INVALID) {
-    if (meta->mm_dbs[FREE_DBI].md_branch_pages ||
-        meta->mm_dbs[FREE_DBI].md_depth || meta->mm_dbs[FREE_DBI].md_entries ||
-        meta->mm_dbs[FREE_DBI].md_leaf_pages ||
-        meta->mm_dbs[FREE_DBI].md_overflow_pages) {
-      mdbx_warning("meta[%u] has false-empty GC, skip it", meta_number);
-      return MDBX_CORRUPTED;
-    }
-  } else if (meta->mm_dbs[FREE_DBI].md_root >= meta->mm_geo.next) {
-    mdbx_warning("meta[%u] has invalid GC-root %" PRIaPGNO ", skip it",
-                 meta_number, meta->mm_dbs[FREE_DBI].md_root);
-    return MDBX_CORRUPTED;
-  }
-
-  /* LY: MainDB root */
-  if (meta->mm_dbs[MAIN_DBI].md_root == P_INVALID) {
-    if (meta->mm_dbs[MAIN_DBI].md_branch_pages ||
-        meta->mm_dbs[MAIN_DBI].md_depth || meta->mm_dbs[MAIN_DBI].md_entries ||
-        meta->mm_dbs[MAIN_DBI].md_leaf_pages ||
-        meta->mm_dbs[MAIN_DBI].md_overflow_pages) {
-      mdbx_warning("meta[%u] has false-empty maindb", meta_number);
-      return MDBX_CORRUPTED;
-    }
-  } else if (meta->mm_dbs[MAIN_DBI].md_root >= meta->mm_geo.next) {
-    mdbx_warning("meta[%u] has invalid maindb-root %" PRIaPGNO ", skip it",
-                 meta_number, meta->mm_dbs[MAIN_DBI].md_root);
-    return MDBX_CORRUPTED;
-  }
-
-  if (unaligned_peek_u64(4, &meta->mm_txnid_a) == 0) {
-    mdbx_warning("meta[%u] has zero txnid, skip it", meta_number);
-    return MDBX_RESULT_TRUE;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-/* Read the environment parameters of a DB environment
- * before mapping it into memory. */
-static __cold int mdbx_read_header(MDBX_env *env, MDBX_meta *dest,
-                                   uint64_t *filesize,
-                                   const int lck_exclusive) {
-  int rc = mdbx_filesize(env->me_lazy_fd, filesize);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  memset(dest, 0, sizeof(MDBX_meta));
-  unaligned_poke_u64(4, dest->mm_datasync_sign, MDBX_DATASIGN_WEAK);
-  rc = MDBX_CORRUPTED;
-
-  /* Read twice all meta pages so we can find the latest one. */
-  unsigned loop_limit = NUM_METAS * 2;
-  for (unsigned loop_count = 0; loop_count < loop_limit; ++loop_count) {
-    /* We don't know the page size on first time.
-     * So, just guess it. */
-    unsigned guess_pagesize = dest->mm_psize;
-    if (guess_pagesize == 0)
-      guess_pagesize =
-          (loop_count > NUM_METAS) ? env->me_psize : env->me_os_psize;
-
-    const unsigned meta_number = loop_count % NUM_METAS;
-    const unsigned offset = guess_pagesize * meta_number;
-
-    char buffer[MIN_PAGESIZE];
-    unsigned retryleft = 42;
-    while (1) {
-      mdbx_trace("reading meta[%d]: offset %u, bytes %u, retry-left %u",
-                 meta_number, offset, MIN_PAGESIZE, retryleft);
-      int err = mdbx_pread(env->me_lazy_fd, buffer, MIN_PAGESIZE, offset);
-      if (err != MDBX_SUCCESS) {
-        if (err == MDBX_ENODATA && offset == 0 && loop_count == 0 &&
-            *filesize == 0 && (env->me_flags & MDBX_RDONLY) == 0)
-          mdbx_warning("read meta: empty file (%d, %s)", err,
-                       mdbx_strerror(err));
-        else
-          mdbx_error("read meta[%u,%u]: %i, %s", offset, MIN_PAGESIZE, err,
-                     mdbx_strerror(err));
-        return err;
-      }
-
-      char again[MIN_PAGESIZE];
-      err = mdbx_pread(env->me_lazy_fd, again, MIN_PAGESIZE, offset);
-      if (err != MDBX_SUCCESS) {
-        mdbx_error("read meta[%u,%u]: %i, %s", offset, MIN_PAGESIZE, err,
-                   mdbx_strerror(err));
-        return err;
-      }
-
-      if (memcmp(buffer, again, MIN_PAGESIZE) == 0 || --retryleft == 0)
-        break;
-
-      mdbx_verbose("meta[%u] was updated, re-read it", meta_number);
-    }
-
-    if (!retryleft) {
-      mdbx_error("meta[%u] is too volatile, skip it", meta_number);
-      continue;
-    }
-
-    MDBX_page *const page = (MDBX_page *)buffer;
-    MDBX_meta *const meta = page_meta(page);
-    rc = mdbx_validate_meta(env, meta, filesize, page, meta_number, dest,
-                            guess_pagesize);
-    if (rc != MDBX_SUCCESS)
-      continue;
-
-    if ((env->me_stuck_meta < 0)
-            ? mdbx_meta_ot(meta_bootid_match(meta) ? prefer_last
-                                                   : prefer_steady,
-                           env, dest, meta)
-            : (meta_number == (unsigned)env->me_stuck_meta)) {
-      *dest = *meta;
-      if (!lck_exclusive && !META_IS_STEADY(dest))
-        loop_limit += 1; /* LY: should re-read to hush race with update */
-      mdbx_verbose("latch meta[%u]", meta_number);
-    }
-  }
-
-  if (dest->mm_psize == 0 ||
-      ((env->me_stuck_meta < 0)
-           ? (!META_IS_STEADY(dest) &&
-              !meta_weak_acceptable(env, dest, lck_exclusive))
-           : false)) {
-    mdbx_error("%s", "no usable meta-pages, database is corrupted");
-    if (rc == MDBX_SUCCESS) {
-      /* TODO: try to restore the database by fully checking b-tree structure
-       * for the each meta page, if the corresponding option was given */
-      return MDBX_CORRUPTED;
-    }
-    return rc;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-static MDBX_page *__cold mdbx_meta_model(const MDBX_env *env, MDBX_page *model,
-                                         unsigned num) {
-
-  mdbx_ensure(env, is_powerof2(env->me_psize));
-  mdbx_ensure(env, env->me_psize >= MIN_PAGESIZE);
-  mdbx_ensure(env, env->me_psize <= MAX_PAGESIZE);
-  mdbx_ensure(env, env->me_dbgeo.lower >= MIN_MAPSIZE);
-  mdbx_ensure(env, env->me_dbgeo.upper <= MAX_MAPSIZE);
-  mdbx_ensure(env, env->me_dbgeo.now >= env->me_dbgeo.lower);
-  mdbx_ensure(env, env->me_dbgeo.now <= env->me_dbgeo.upper);
-
-  memset(model, 0, sizeof(*model));
-  model->mp_pgno = num;
-  model->mp_flags = P_META;
-  MDBX_meta *const model_meta = page_meta(model);
-  unaligned_poke_u64(4, model_meta->mm_magic_and_version, MDBX_DATA_MAGIC);
-
-  model_meta->mm_geo.lower = bytes2pgno(env, env->me_dbgeo.lower);
-  model_meta->mm_geo.upper = bytes2pgno(env, env->me_dbgeo.upper);
-  model_meta->mm_geo.grow = (uint16_t)bytes2pgno(env, env->me_dbgeo.grow);
-  model_meta->mm_geo.shrink = (uint16_t)bytes2pgno(env, env->me_dbgeo.shrink);
-  model_meta->mm_geo.now = bytes2pgno(env, env->me_dbgeo.now);
-  model_meta->mm_geo.next = NUM_METAS;
-
-  mdbx_ensure(env, model_meta->mm_geo.lower >= MIN_PAGENO);
-  mdbx_ensure(env, model_meta->mm_geo.upper <= MAX_PAGENO);
-  mdbx_ensure(env, model_meta->mm_geo.now >= model_meta->mm_geo.lower);
-  mdbx_ensure(env, model_meta->mm_geo.now <= model_meta->mm_geo.upper);
-  mdbx_ensure(env, model_meta->mm_geo.next >= MIN_PAGENO);
-  mdbx_ensure(env, model_meta->mm_geo.next <= model_meta->mm_geo.now);
-  mdbx_ensure(env,
-              model_meta->mm_geo.grow == bytes2pgno(env, env->me_dbgeo.grow));
-  mdbx_ensure(env, model_meta->mm_geo.shrink ==
-                       bytes2pgno(env, env->me_dbgeo.shrink));
-
-  model_meta->mm_psize = env->me_psize;
-  model_meta->mm_flags = (uint16_t)env->me_flags;
-  model_meta->mm_flags |=
-      MDBX_INTEGERKEY; /* this is mm_dbs[FREE_DBI].md_flags */
-  model_meta->mm_dbs[FREE_DBI].md_root = P_INVALID;
-  model_meta->mm_dbs[MAIN_DBI].md_root = P_INVALID;
-  mdbx_meta_set_txnid(env, model_meta, MIN_TXNID + num);
-  unaligned_poke_u64(4, model_meta->mm_datasync_sign,
-                     mdbx_meta_sign(model_meta));
-  return (MDBX_page *)((uint8_t *)model + env->me_psize);
-}
-
-/* Fill in most of the zeroed meta-pages for an empty database environment.
- * Return pointer to recently (head) meta-page. */
-static MDBX_meta *__cold mdbx_init_metas(const MDBX_env *env, void *buffer) {
-  MDBX_page *page0 = (MDBX_page *)buffer;
-  MDBX_page *page1 = mdbx_meta_model(env, page0, 0);
-  MDBX_page *page2 = mdbx_meta_model(env, page1, 1);
-  mdbx_meta_model(env, page2, 2);
-  mdbx_assert(env, !mdbx_meta_eq(env, page_meta(page0), page_meta(page1)));
-  mdbx_assert(env, !mdbx_meta_eq(env, page_meta(page1), page_meta(page2)));
-  mdbx_assert(env, !mdbx_meta_eq(env, page_meta(page2), page_meta(page0)));
-  return page_meta(page2);
-}
-
-static size_t mdbx_madvise_threshold(const MDBX_env *env,
-                                     const size_t largest_bytes) {
-  /* TODO: use options */
-  const unsigned factor = 9;
-  const size_t threshold = (largest_bytes < (65536ul << factor))
-                               ? 65536 /* minimal threshold */
-                               : (largest_bytes > (MEGABYTE * 4 << factor))
-                                     ? MEGABYTE * 4 /* maximal threshold */
-                                     : largest_bytes >> factor;
-  return bytes_align2os_bytes(env, threshold);
-}
-
-static int mdbx_sync_locked(MDBX_env *env, unsigned flags,
-                            MDBX_meta *const pending) {
-  mdbx_assert(env, ((env->me_flags ^ flags) & MDBX_WRITEMAP) == 0);
-  MDBX_meta *const meta0 = METAPAGE(env, 0);
-  MDBX_meta *const meta1 = METAPAGE(env, 1);
-  MDBX_meta *const meta2 = METAPAGE(env, 2);
-  MDBX_meta *const head = mdbx_meta_head(env);
-  int rc;
-
-  mdbx_assert(env, mdbx_meta_eq_mask(env) == 0);
-  mdbx_assert(env,
-              pending < METAPAGE(env, 0) || pending > METAPAGE(env, NUM_METAS));
-  mdbx_assert(env, (env->me_flags & (MDBX_RDONLY | MDBX_FATAL_ERROR)) == 0);
-  mdbx_assert(env, pending->mm_geo.next <= pending->mm_geo.now);
-
-  if (flags & MDBX_SAFE_NOSYNC) {
-    /* Check auto-sync conditions */
-    const pgno_t autosync_threshold =
-        atomic_load32(env->me_autosync_threshold, mo_Relaxed);
-    const uint64_t autosync_period =
-        atomic_load64(env->me_autosync_period, mo_Relaxed);
-    if ((autosync_threshold &&
-         atomic_load32(env->me_unsynced_pages, mo_Relaxed) >=
-             autosync_threshold) ||
-        (autosync_period &&
-         mdbx_osal_monotime() -
-                 atomic_load64(env->me_sync_timestamp, mo_Relaxed) >=
-             autosync_period))
-      flags &= MDBX_WRITEMAP | MDBX_SHRINK_ALLOWED; /* force steady */
-  }
-
-  pgno_t shrink = 0;
-  if (flags & MDBX_SHRINK_ALLOWED) {
-    /* LY: check conditions to discard unused pages */
-    const pgno_t largest_pgno = mdbx_find_largest(
-        env, (head->mm_geo.next > pending->mm_geo.next) ? head->mm_geo.next
-                                                        : pending->mm_geo.next);
-    mdbx_assert(env, largest_pgno >= NUM_METAS);
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-    const pgno_t edge = env->me_poison_edge;
-    if (edge > largest_pgno) {
-      env->me_poison_edge = largest_pgno;
-      VALGRIND_MAKE_MEM_NOACCESS(env->me_map + pgno2bytes(env, largest_pgno),
-                                 pgno2bytes(env, edge - largest_pgno));
-      ASAN_POISON_MEMORY_REGION(env->me_map + pgno2bytes(env, largest_pgno),
-                                pgno2bytes(env, edge - largest_pgno));
-    }
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-#if defined(MADV_DONTNEED)
-    const size_t largest_bytes = pgno2bytes(env, largest_pgno);
-    /* threshold to avoid unreasonable frequent madvise() calls */
-    const size_t madvise_threshold = mdbx_madvise_threshold(env, largest_bytes);
-    const size_t discard_edge_bytes = bytes_align2os_bytes(
-        env, ((MDBX_RDONLY &
-               (env->me_lck ? env->me_lck->mti_envmode.weak : env->me_flags))
-                  ? largest_bytes
-                  : largest_bytes + madvise_threshold));
-    const pgno_t discard_edge_pgno = bytes2pgno(env, discard_edge_bytes);
-    const pgno_t prev_discarded_pgno =
-        atomic_load32(env->me_discarded_tail, mo_AcquireRelease);
-    if (prev_discarded_pgno >=
-        discard_edge_pgno + bytes2pgno(env, madvise_threshold)) {
-      mdbx_notice("open-MADV_%s %u..%u", "DONTNEED", prev_discarded_pgno,
-                  largest_pgno);
-      atomic_store32(env->me_discarded_tail, discard_edge_pgno,
-                     mo_AcquireRelease);
-      const size_t prev_discarded_bytes =
-          ceil_powerof2(pgno2bytes(env, prev_discarded_pgno), env->me_os_psize);
-      mdbx_ensure(env, prev_discarded_bytes > discard_edge_bytes);
-      int advise = MADV_DONTNEED;
-#if defined(MADV_FREE) &&                                                      \
-    0 /* MADV_FREE works for only anonymous vma at the moment */
-      if ((env->me_flags & MDBX_WRITEMAP) &&
-          mdbx_linux_kernel_version > 0x04050000)
-        advise = MADV_FREE;
-#endif /* MADV_FREE */
-      int err = madvise(env->me_map + discard_edge_bytes,
-                        prev_discarded_bytes - discard_edge_bytes, advise)
-                    ? ignore_enosys(errno)
-                    : MDBX_SUCCESS;
-      if (unlikely(MDBX_IS_ERROR(err)))
-        return err;
-    }
-#endif /* MADV_FREE || MADV_DONTNEED */
-
-    /* LY: check conditions to shrink datafile */
-    const pgno_t backlog_gap = 3 + pending->mm_dbs[FREE_DBI].md_depth * 3;
-    if (pending->mm_geo.shrink && pending->mm_geo.now - pending->mm_geo.next >
-                                      pending->mm_geo.shrink + backlog_gap) {
-      if (pending->mm_geo.now > largest_pgno &&
-          pending->mm_geo.now - largest_pgno >
-              pending->mm_geo.shrink + backlog_gap) {
-        const pgno_t aligner = pending->mm_geo.grow ? pending->mm_geo.grow
-                                                    : pending->mm_geo.shrink;
-        const pgno_t with_backlog_gap = largest_pgno + backlog_gap;
-        const pgno_t aligned = pgno_align2os_pgno(
-            env, with_backlog_gap + aligner - with_backlog_gap % aligner);
-        const pgno_t bottom =
-            (aligned > pending->mm_geo.lower) ? aligned : pending->mm_geo.lower;
-        if (pending->mm_geo.now > bottom) {
-          if (META_IS_STEADY(mdbx_meta_steady(env)))
-            /* force steady, but only if steady-checkpoint is present */
-            flags &= MDBX_WRITEMAP | MDBX_SHRINK_ALLOWED;
-          shrink = pending->mm_geo.now - bottom;
-          pending->mm_geo.now = bottom;
-          if (unlikely(mdbx_meta_txnid_stable(env, head) ==
-                       unaligned_peek_u64(4, pending->mm_txnid_a))) {
-            const txnid_t txnid =
-                safe64_txnid_next(unaligned_peek_u64(4, pending->mm_txnid_a));
-            if (unlikely(txnid > MAX_TXNID)) {
-              rc = MDBX_TXN_FULL;
-              mdbx_error("txnid overflow, raise %d", rc);
-              goto fail;
-            }
-            mdbx_meta_set_txnid(env, pending, txnid);
-          }
-        }
-      }
-    }
-  }
-
-  /* LY: step#1 - sync previously written/updated data-pages */
-  rc = MDBX_RESULT_FALSE /* carry steady */;
-  if (atomic_load32(env->me_unsynced_pages, mo_AcquireRelease)) {
-    mdbx_assert(env, ((flags ^ env->me_flags) & MDBX_WRITEMAP) == 0);
-    enum mdbx_syncmode_bits mode_bits = MDBX_SYNC_NONE;
-    if ((flags & MDBX_SAFE_NOSYNC) == 0) {
-      mode_bits = MDBX_SYNC_DATA;
-      if (pending->mm_geo.next > mdbx_meta_steady(env)->mm_geo.now)
-        mode_bits |= MDBX_SYNC_SIZE;
-      if (flags & MDBX_NOMETASYNC)
-        mode_bits |= MDBX_SYNC_IODQ;
-    }
-    if (flags & MDBX_WRITEMAP)
-      rc =
-          mdbx_msync(&env->me_dxb_mmap, 0,
-                     pgno_align2os_bytes(env, pending->mm_geo.next), mode_bits);
-    else
-      rc = mdbx_fsync(env->me_lazy_fd, mode_bits);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto fail;
-    rc = (flags & MDBX_SAFE_NOSYNC) ? MDBX_RESULT_TRUE /* carry non-steady */
-                                    : MDBX_RESULT_FALSE /* carry steady */;
-  }
-
-  /* Steady or Weak */
-  if (rc == MDBX_RESULT_FALSE /* carry steady */) {
-    atomic_store64(env->me_sync_timestamp, mdbx_osal_monotime(), mo_Relaxed);
-    unaligned_poke_u64(4, pending->mm_datasync_sign, mdbx_meta_sign(pending));
-    atomic_store32(env->me_unsynced_pages, 0, mo_AcquireRelease);
-  } else {
-    assert(rc == MDBX_RESULT_TRUE /* carry non-steady */);
-    unaligned_poke_u64(4, pending->mm_datasync_sign, MDBX_DATASIGN_WEAK);
-  }
-
-  MDBX_meta *target = nullptr;
-  if (mdbx_meta_txnid_stable(env, head) ==
-      unaligned_peek_u64(4, pending->mm_txnid_a)) {
-    mdbx_assert(env, memcmp(&head->mm_dbs, &pending->mm_dbs,
-                            sizeof(head->mm_dbs)) == 0);
-    mdbx_assert(env, memcmp(&head->mm_canary, &pending->mm_canary,
-                            sizeof(head->mm_canary)) == 0);
-    mdbx_assert(env, memcmp(&head->mm_geo, &pending->mm_geo,
-                            sizeof(pending->mm_geo)) == 0);
-    if (!META_IS_STEADY(head) && META_IS_STEADY(pending))
-      target = head;
-    else {
-      mdbx_ensure(env, mdbx_meta_eq(env, head, pending));
-      mdbx_debug("%s", "skip update meta");
-      return MDBX_SUCCESS;
-    }
-  } else if (head == meta0)
-    target = mdbx_meta_ancient(prefer_steady, env, meta1, meta2);
-  else if (head == meta1)
-    target = mdbx_meta_ancient(prefer_steady, env, meta0, meta2);
-  else {
-    mdbx_assert(env, head == meta2);
-    target = mdbx_meta_ancient(prefer_steady, env, meta0, meta1);
-  }
-
-  /* LY: step#2 - update meta-page. */
-  mdbx_debug("writing meta%" PRIaPGNO " = root %" PRIaPGNO "/%" PRIaPGNO
-             ", geo %" PRIaPGNO "/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
-             " +%u -%u, txn_id %" PRIaTXN ", %s",
-             data_page(target)->mp_pgno, pending->mm_dbs[MAIN_DBI].md_root,
-             pending->mm_dbs[FREE_DBI].md_root, pending->mm_geo.lower,
-             pending->mm_geo.next, pending->mm_geo.now, pending->mm_geo.upper,
-             pending->mm_geo.grow, pending->mm_geo.shrink,
-             unaligned_peek_u64(4, pending->mm_txnid_a),
-             mdbx_durable_str(pending));
-
-  mdbx_debug("meta0: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
-             "/%" PRIaPGNO,
-             (meta0 == head) ? "head" : (meta0 == target) ? "tail" : "stay",
-             mdbx_durable_str(meta0), mdbx_meta_txnid_fluid(env, meta0),
-             meta0->mm_dbs[MAIN_DBI].md_root, meta0->mm_dbs[FREE_DBI].md_root);
-  mdbx_debug("meta1: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
-             "/%" PRIaPGNO,
-             (meta1 == head) ? "head" : (meta1 == target) ? "tail" : "stay",
-             mdbx_durable_str(meta1), mdbx_meta_txnid_fluid(env, meta1),
-             meta1->mm_dbs[MAIN_DBI].md_root, meta1->mm_dbs[FREE_DBI].md_root);
-  mdbx_debug("meta2: %s, %s, txn_id %" PRIaTXN ", root %" PRIaPGNO
-             "/%" PRIaPGNO,
-             (meta2 == head) ? "head" : (meta2 == target) ? "tail" : "stay",
-             mdbx_durable_str(meta2), mdbx_meta_txnid_fluid(env, meta2),
-             meta2->mm_dbs[MAIN_DBI].md_root, meta2->mm_dbs[FREE_DBI].md_root);
-
-  mdbx_assert(env, !mdbx_meta_eq(env, pending, meta0));
-  mdbx_assert(env, !mdbx_meta_eq(env, pending, meta1));
-  mdbx_assert(env, !mdbx_meta_eq(env, pending, meta2));
-
-  mdbx_assert(env, ((env->me_flags ^ flags) & MDBX_WRITEMAP) == 0);
-  mdbx_ensure(env,
-              target == head || mdbx_meta_txnid_stable(env, target) <
-                                    unaligned_peek_u64(4, pending->mm_txnid_a));
-  if (flags & MDBX_WRITEMAP) {
-    mdbx_jitter4testing(true);
-    if (likely(target != head)) {
-      /* LY: 'invalidate' the meta. */
-      mdbx_meta_update_begin(env, target,
-                             unaligned_peek_u64(4, pending->mm_txnid_a));
-      unaligned_poke_u64(4, target->mm_datasync_sign, MDBX_DATASIGN_WEAK);
-#ifndef NDEBUG
-      /* debug: provoke failure to catch a violators, but don't touch mm_psize
-       * and mm_flags to allow readers catch actual pagesize. */
-      uint8_t *provoke_begin = (uint8_t *)&target->mm_dbs[FREE_DBI].md_root;
-      uint8_t *provoke_end = (uint8_t *)&target->mm_datasync_sign;
-      memset(provoke_begin, 0xCC, provoke_end - provoke_begin);
-      mdbx_jitter4testing(false);
-#endif
-
-      /* LY: update info */
-      target->mm_geo = pending->mm_geo;
-      target->mm_dbs[FREE_DBI] = pending->mm_dbs[FREE_DBI];
-      target->mm_dbs[MAIN_DBI] = pending->mm_dbs[MAIN_DBI];
-      target->mm_canary = pending->mm_canary;
-      memcpy(target->mm_pages_retired, pending->mm_pages_retired, 8);
-      mdbx_jitter4testing(true);
-
-      /* LY: 'commit' the meta */
-      mdbx_meta_update_end(env, target,
-                           unaligned_peek_u64(4, pending->mm_txnid_b));
-      mdbx_jitter4testing(true);
-    } else {
-      /* dangerous case (target == head), only mm_datasync_sign could
-       * me updated, check assertions once again */
-      mdbx_ensure(env, mdbx_meta_txnid_stable(env, head) ==
-                               unaligned_peek_u64(4, pending->mm_txnid_a) &&
-                           !META_IS_STEADY(head) && META_IS_STEADY(pending));
-      mdbx_ensure(env, memcmp(&head->mm_geo, &pending->mm_geo,
-                              sizeof(head->mm_geo)) == 0);
-      mdbx_ensure(env, memcmp(&head->mm_dbs, &pending->mm_dbs,
-                              sizeof(head->mm_dbs)) == 0);
-      mdbx_ensure(env, memcmp(&head->mm_canary, &pending->mm_canary,
-                              sizeof(head->mm_canary)) == 0);
-    }
-    memcpy(target->mm_datasync_sign, pending->mm_datasync_sign, 8);
-    mdbx_flush_incoherent_cpu_writeback();
-    mdbx_jitter4testing(true);
-    /* sync meta-pages */
-    rc =
-        mdbx_msync(&env->me_dxb_mmap, 0, pgno_align2os_bytes(env, NUM_METAS),
-                   (flags & MDBX_NOMETASYNC) ? MDBX_SYNC_NONE
-                                             : MDBX_SYNC_DATA | MDBX_SYNC_IODQ);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto fail;
-  } else {
-    const MDBX_meta undo_meta = *target;
-    const mdbx_filehandle_t fd = (env->me_dsync_fd != INVALID_HANDLE_VALUE)
-                                     ? env->me_dsync_fd
-                                     : env->me_lazy_fd;
-    rc = mdbx_pwrite(fd, pending, sizeof(MDBX_meta),
-                     (uint8_t *)target - env->me_map);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-    undo:
-      mdbx_debug("%s", "write failed, disk error?");
-      /* On a failure, the pagecache still contains the new data.
-       * Try write some old data back, to prevent it from being used. */
-      mdbx_pwrite(fd, &undo_meta, sizeof(MDBX_meta),
-                  (uint8_t *)target - env->me_map);
-      goto fail;
-    }
-    mdbx_flush_incoherent_mmap(target, sizeof(MDBX_meta), env->me_os_psize);
-    /* sync meta-pages */
-    if ((flags & MDBX_NOMETASYNC) == 0 && fd == env->me_lazy_fd) {
-      rc = mdbx_fsync(env->me_lazy_fd, MDBX_SYNC_DATA | MDBX_SYNC_IODQ);
-      if (rc != MDBX_SUCCESS)
-        goto undo;
-    }
-  }
-  if (flags & MDBX_NOMETASYNC)
-    env->me_unsynced_pages->weak += 1;
-  else
-    env->me_meta_sync_txnid->weak =
-        (uint32_t)unaligned_peek_u64(4, pending->mm_txnid_a);
-
-  /* LY: shrink datafile if needed */
-  if (unlikely(shrink)) {
-    mdbx_verbose("shrink to %" PRIaPGNO " pages (-%" PRIaPGNO ")",
-                 pending->mm_geo.now, shrink);
-    rc = mdbx_mapresize_implicit(env, pending->mm_geo.next, pending->mm_geo.now,
-                                 pending->mm_geo.upper);
-    if (MDBX_IS_ERROR(rc))
-      goto fail;
-  }
-
-  if (likely(env->me_lck))
-    /* toggle oldest refresh */
-    atomic_store32(&env->me_lck->mti_readers_refresh_flag, false,
-                   mo_AcquireRelease);
-
-  return MDBX_SUCCESS;
-
-fail:
-  env->me_flags |= MDBX_FATAL_ERROR;
-  return rc;
-}
-
-static void __cold mdbx_setup_pagesize(MDBX_env *env, const size_t pagesize) {
-  STATIC_ASSERT(PTRDIFF_MAX > MAX_MAPSIZE);
-  STATIC_ASSERT(MIN_PAGESIZE > sizeof(MDBX_page) + sizeof(MDBX_meta));
-  mdbx_ensure(env, is_powerof2(pagesize));
-  mdbx_ensure(env, pagesize >= MIN_PAGESIZE);
-  mdbx_ensure(env, pagesize <= MAX_PAGESIZE);
-  env->me_psize = (unsigned)pagesize;
-
-  STATIC_ASSERT(MAX_GC1OVPAGE(MIN_PAGESIZE) > 4);
-  STATIC_ASSERT(MAX_GC1OVPAGE(MAX_PAGESIZE) < MDBX_PGL_LIMIT / 4);
-  const intptr_t maxgc_ov1page = (pagesize - PAGEHDRSZ) / sizeof(pgno_t) - 1;
-  mdbx_ensure(env, maxgc_ov1page > 42 &&
-                       maxgc_ov1page < (intptr_t)MDBX_PGL_LIMIT / 4);
-  env->me_maxgc_ov1page = (unsigned)maxgc_ov1page;
-
-  STATIC_ASSERT(LEAF_NODEMAX(MIN_PAGESIZE) > sizeof(MDBX_db) + NODESIZE + 42);
-  STATIC_ASSERT(LEAF_NODEMAX(MAX_PAGESIZE) < UINT16_MAX);
-  STATIC_ASSERT(LEAF_NODEMAX(MIN_PAGESIZE) > BRANCH_NODEMAX(MIN_PAGESIZE));
-  STATIC_ASSERT(BRANCH_NODEMAX(MAX_PAGESIZE) > NODESIZE + 42);
-  STATIC_ASSERT(BRANCH_NODEMAX(MAX_PAGESIZE) < UINT16_MAX);
-  const intptr_t branch_nodemax = BRANCH_NODEMAX(pagesize);
-  mdbx_ensure(env, branch_nodemax > 42 && branch_nodemax < (int)UINT16_MAX &&
-                       branch_nodemax % 2 == 0);
-  env->me_branch_nodemax = (unsigned)branch_nodemax;
-  env->me_psize2log = (uint8_t)log2n(pagesize);
-  mdbx_assert(env, pgno2bytes(env, 1) == pagesize);
-  mdbx_assert(env, bytes2pgno(env, pagesize + pagesize) == 2);
-
-  const pgno_t max_pgno = bytes2pgno(env, MAX_MAPSIZE);
-  if (env->me_options.dp_limit > max_pgno - NUM_METAS)
-    env->me_options.dp_limit = max_pgno - NUM_METAS;
-  if (env->me_options.dp_initial > env->me_options.dp_limit)
-    env->me_options.dp_initial = env->me_options.dp_limit;
-}
-
-__cold int mdbx_env_create(MDBX_env **penv) {
-  MDBX_env *env = mdbx_calloc(1, sizeof(MDBX_env));
-  if (unlikely(!env))
-    return MDBX_ENOMEM;
-
-  env->me_maxreaders = DEFAULT_READERS;
-  env->me_maxdbs = env->me_numdbs = CORE_DBS;
-  env->me_lazy_fd = INVALID_HANDLE_VALUE;
-  env->me_dsync_fd = INVALID_HANDLE_VALUE;
-  env->me_lfd = INVALID_HANDLE_VALUE;
-  env->me_pid = mdbx_getpid();
-  env->me_stuck_meta = -1;
-
-  env->me_options.dp_reserve_limit = 1024;
-  env->me_options.rp_augment_limit = 256 * 1024;
-  env->me_options.dp_limit = 64 * 1024;
-  if (env->me_options.dp_limit > MAX_PAGENO - NUM_METAS)
-    env->me_options.dp_limit = MAX_PAGENO - NUM_METAS;
-  env->me_options.dp_initial = MDBX_PNL_INITIAL;
-  if (env->me_options.dp_initial > env->me_options.dp_limit)
-    env->me_options.dp_initial = env->me_options.dp_limit;
-  env->me_options.spill_max_denominator = 8;
-  env->me_options.spill_min_denominator = 8;
-  env->me_options.spill_parent4child_denominator = 0;
-  env->me_options.dp_loose_limit = 64;
-
-  int rc;
-  const size_t os_psize = mdbx_syspagesize();
-  if (unlikely(!is_powerof2(os_psize) || os_psize < MIN_PAGESIZE)) {
-    mdbx_error("unsuitable system pagesize %" PRIuPTR, os_psize);
-    rc = MDBX_INCOMPATIBLE;
-    goto bailout;
-  }
-  env->me_os_psize = (unsigned)os_psize;
-  mdbx_setup_pagesize(env, (env->me_os_psize < MAX_PAGESIZE) ? env->me_os_psize
-                                                             : MAX_PAGESIZE);
-
-  rc = mdbx_fastmutex_init(&env->me_dbi_lock);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto bailout;
-
-#if defined(_WIN32) || defined(_WIN64)
-  mdbx_srwlock_Init(&env->me_remap_guard);
-  InitializeCriticalSection(&env->me_windowsbug_lock);
-#else
-  rc = mdbx_fastmutex_init(&env->me_remap_guard);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    mdbx_fastmutex_destroy(&env->me_dbi_lock);
-    goto bailout;
-  }
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV
-  rc = mdbx_ipclock_stub(&env->me_lckless_stub.wlock);
-#endif /* MDBX_LOCKING */
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    mdbx_fastmutex_destroy(&env->me_remap_guard);
-    mdbx_fastmutex_destroy(&env->me_dbi_lock);
-    goto bailout;
-  }
-#endif /* Windows */
-
-  VALGRIND_CREATE_MEMPOOL(env, 0, 0);
-  env->me_signature.weak = MDBX_ME_SIGNATURE;
-  *penv = env;
-  return MDBX_SUCCESS;
-
-bailout:
-  mdbx_free(env);
-  *penv = nullptr;
-  return rc;
-}
-
-__cold LIBMDBX_API int
-mdbx_env_set_geometry(MDBX_env *env, intptr_t size_lower, intptr_t size_now,
-                      intptr_t size_upper, intptr_t growth_step,
-                      intptr_t shrink_threshold, intptr_t pagesize) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  const bool inside_txn =
-      (env->me_txn0 && env->me_txn0->mt_owner == mdbx_thread_self());
-
-#if MDBX_DEBUG
-  if (growth_step < 0)
-    growth_step = 1;
-  if (shrink_threshold < 0)
-    shrink_threshold = 1;
-#endif
-
-  bool need_unlock = false;
-  rc = MDBX_PROBLEM;
-  if (env->me_map) {
-    /* env already mapped */
-    if (unlikely(env->me_flags & MDBX_RDONLY))
-      return MDBX_EACCESS;
-
-    if (!inside_txn) {
-      int err = mdbx_txn_lock(env, false);
-      if (unlikely(err != MDBX_SUCCESS))
-        return err;
-      need_unlock = true;
-    }
-    MDBX_meta *head = mdbx_meta_head(env);
-    if (!inside_txn) {
-      env->me_txn0->mt_txnid = meta_txnid(env, head, false);
-      mdbx_find_oldest(env->me_txn0);
-    }
-
-    /* get untouched params from DB */
-    if (pagesize <= 0 || pagesize >= INT_MAX)
-      pagesize = env->me_psize;
-    if (size_lower < 0)
-      size_lower = pgno2bytes(env, head->mm_geo.lower);
-    if (size_now < 0)
-      size_now = pgno2bytes(env, head->mm_geo.now);
-    if (size_upper < 0)
-      size_upper = pgno2bytes(env, head->mm_geo.upper);
-    if (growth_step < 0)
-      growth_step = pgno2bytes(env, head->mm_geo.grow);
-    if (shrink_threshold < 0)
-      shrink_threshold = pgno2bytes(env, head->mm_geo.shrink);
-
-    if (pagesize != (intptr_t)env->me_psize) {
-      rc = MDBX_EINVAL;
-      goto bailout;
-    }
-    const size_t usedbytes =
-        pgno2bytes(env, mdbx_find_largest(env, head->mm_geo.next));
-    if ((size_t)size_upper < usedbytes) {
-      rc = MDBX_MAP_FULL;
-      goto bailout;
-    }
-    if ((size_t)size_now < usedbytes)
-      size_now = usedbytes;
-  } else {
-    /* env NOT yet mapped */
-    if (unlikely(inside_txn))
-      return MDBX_PANIC;
-
-    /* is requested some auto-value for pagesize ? */
-    if (pagesize >= INT_MAX /* maximal */)
-      pagesize = MAX_PAGESIZE;
-    else if (pagesize <= 0) {
-      if (pagesize < 0 /* default */) {
-        pagesize = env->me_os_psize;
-        if ((uintptr_t)pagesize > MAX_PAGESIZE)
-          pagesize = MAX_PAGESIZE;
-        mdbx_assert(env, (uintptr_t)pagesize >= MIN_PAGESIZE);
-      } else if (pagesize == 0 /* minimal */)
-        pagesize = MIN_PAGESIZE;
-
-      /* choose pagesize */
-      intptr_t max_size = (size_now > size_lower) ? size_now : size_lower;
-      max_size = (size_upper > max_size) ? size_upper : max_size;
-      if (max_size < 0 /* default */)
-        max_size = DEFAULT_MAPSIZE;
-      else if (max_size == 0 /* minimal */)
-        max_size = MIN_MAPSIZE;
-      else if (max_size >= (intptr_t)MAX_MAPSIZE /* maximal */)
-        max_size = MAX_MAPSIZE;
-
-      while (max_size > pagesize * (int64_t)MAX_PAGENO &&
-             pagesize < MAX_PAGESIZE)
-        pagesize <<= 1;
-    }
-  }
-
-  if (pagesize < (intptr_t)MIN_PAGESIZE || pagesize > (intptr_t)MAX_PAGESIZE ||
-      !is_powerof2(pagesize)) {
-    rc = MDBX_EINVAL;
-    goto bailout;
-  }
-
-  if (size_lower <= 0) {
-    size_lower = MIN_MAPSIZE;
-    if (MIN_MAPSIZE / pagesize < MIN_PAGENO)
-      size_lower = MIN_PAGENO * pagesize;
-  }
-  if (size_lower == INTPTR_MAX)
-    size_lower = MAX_MAPSIZE;
-
-  if (size_now <= 0) {
-    size_now = DEFAULT_MAPSIZE;
-    if (size_now < size_lower)
-      size_now = size_lower;
-    if (size_upper >= size_lower && size_now > size_upper)
-      size_now = size_upper;
-  }
-  if (size_now == INTPTR_MAX)
-    size_now = MAX_MAPSIZE;
-
-  if (size_upper <= 0) {
-    if ((size_t)size_now >= MAX_MAPSIZE / 2)
-      size_upper = MAX_MAPSIZE;
-    else if (MAX_MAPSIZE != MAX_MAPSIZE32 &&
-             (size_t)size_now >= MAX_MAPSIZE32 / 2 &&
-             (size_t)size_now <= MAX_MAPSIZE32 / 4 * 3)
-      size_upper = MAX_MAPSIZE32;
-    else {
-      size_upper = size_now + size_now;
-      if ((size_t)size_upper < DEFAULT_MAPSIZE * 2)
-        size_upper = DEFAULT_MAPSIZE * 2;
-    }
-    if ((size_t)size_upper / pagesize > MAX_PAGENO)
-      size_upper = pagesize * MAX_PAGENO;
-  }
-
-  if (unlikely(size_lower < (intptr_t)MIN_MAPSIZE || size_lower > size_upper)) {
-    rc = MDBX_EINVAL;
-    goto bailout;
-  }
-
-  if ((uint64_t)size_lower / pagesize < MIN_PAGENO) {
-    rc = MDBX_EINVAL;
-    goto bailout;
-  }
-
-  if (unlikely((size_t)size_upper > MAX_MAPSIZE ||
-               (uint64_t)size_upper / pagesize > MAX_PAGENO)) {
-    rc = MDBX_TOO_LARGE;
-    goto bailout;
-  }
-
-  const size_t unit = (env->me_os_psize > (size_t)pagesize) ? env->me_os_psize
-                                                            : (size_t)pagesize;
-  size_lower = ceil_powerof2(size_lower, unit);
-  size_upper = ceil_powerof2(size_upper, unit);
-  size_now = ceil_powerof2(size_now, unit);
-
-  /* LY: подбираем значение size_upper:
-   *  - кратное размеру страницы
-   *  - без нарушения MAX_MAPSIZE и MAX_PAGENO */
-  while (unlikely((size_t)size_upper > MAX_MAPSIZE ||
-                  (uint64_t)size_upper / pagesize > MAX_PAGENO)) {
-    if ((size_t)size_upper < unit + MIN_MAPSIZE ||
-        (size_t)size_upper < (size_t)pagesize * (MIN_PAGENO + 1)) {
-      /* паранойа на случай переполнения при невероятных значениях */
-      rc = MDBX_EINVAL;
-      goto bailout;
-    }
-    size_upper -= unit;
-    if ((size_t)size_upper < (size_t)size_lower)
-      size_lower = size_upper;
-  }
-  mdbx_assert(env, (size_upper - size_lower) % env->me_os_psize == 0);
-
-  if (size_now < size_lower)
-    size_now = size_lower;
-  if (size_now > size_upper)
-    size_now = size_upper;
-
-  if (growth_step < 0) {
-    growth_step = ((size_t)(size_upper - size_lower)) / 42;
-    if (growth_step > size_lower)
-      growth_step = size_lower;
-    if (growth_step < 65536)
-      growth_step = 65536;
-    if ((size_t)growth_step > MEGABYTE * 16)
-      growth_step = MEGABYTE * 16;
-  }
-  if (growth_step == 0 && shrink_threshold > 0)
-    growth_step = 1;
-  growth_step = ceil_powerof2(growth_step, unit);
-  if (bytes2pgno(env, growth_step) > UINT16_MAX)
-    growth_step = pgno2bytes(env, UINT16_MAX);
-
-  if (shrink_threshold < 0)
-    shrink_threshold = growth_step + growth_step;
-  shrink_threshold = ceil_powerof2(shrink_threshold, unit);
-  if (bytes2pgno(env, shrink_threshold) > UINT16_MAX)
-    shrink_threshold = pgno2bytes(env, UINT16_MAX);
-
-  /* save user's geo-params for future open/create */
-  env->me_dbgeo.lower = size_lower;
-  env->me_dbgeo.now = size_now;
-  env->me_dbgeo.upper = size_upper;
-  env->me_dbgeo.grow = growth_step;
-  env->me_dbgeo.shrink = shrink_threshold;
-  rc = MDBX_SUCCESS;
-
-  mdbx_ensure(env, pagesize >= MIN_PAGESIZE);
-  mdbx_ensure(env, pagesize <= MAX_PAGESIZE);
-  mdbx_ensure(env, is_powerof2(pagesize));
-  mdbx_ensure(env, is_powerof2(env->me_os_psize));
-
-  mdbx_ensure(env, env->me_dbgeo.lower >= MIN_MAPSIZE);
-  mdbx_ensure(env, env->me_dbgeo.lower / pagesize >= MIN_PAGENO);
-  mdbx_ensure(env, env->me_dbgeo.lower % pagesize == 0);
-  mdbx_ensure(env, env->me_dbgeo.lower % env->me_os_psize == 0);
-
-  mdbx_ensure(env, env->me_dbgeo.upper <= MAX_MAPSIZE);
-  mdbx_ensure(env, env->me_dbgeo.upper / pagesize <= MAX_PAGENO);
-  mdbx_ensure(env, env->me_dbgeo.upper % pagesize == 0);
-  mdbx_ensure(env, env->me_dbgeo.upper % env->me_os_psize == 0);
-
-  mdbx_ensure(env, env->me_dbgeo.now >= env->me_dbgeo.lower);
-  mdbx_ensure(env, env->me_dbgeo.now <= env->me_dbgeo.upper);
-  mdbx_ensure(env, env->me_dbgeo.now % pagesize == 0);
-  mdbx_ensure(env, env->me_dbgeo.now % env->me_os_psize == 0);
-
-  mdbx_ensure(env, env->me_dbgeo.grow % pagesize == 0);
-  mdbx_ensure(env, env->me_dbgeo.grow % env->me_os_psize == 0);
-  mdbx_ensure(env, env->me_dbgeo.shrink % pagesize == 0);
-  mdbx_ensure(env, env->me_dbgeo.shrink % env->me_os_psize == 0);
-
-  if (env->me_map) {
-    /* apply new params to opened environment */
-    mdbx_ensure(env, pagesize == (intptr_t)env->me_psize);
-    MDBX_meta meta;
-    MDBX_meta *head = nullptr;
-    const mdbx_geo_t *current_geo;
-    if (inside_txn) {
-      current_geo = &env->me_txn->mt_geo;
-    } else {
-      head = mdbx_meta_head(env);
-      meta = *head;
-      current_geo = &meta.mm_geo;
-    }
-
-    mdbx_geo_t new_geo;
-    new_geo.lower = bytes2pgno(env, env->me_dbgeo.lower);
-    new_geo.now = bytes2pgno(env, env->me_dbgeo.now);
-    new_geo.upper = bytes2pgno(env, env->me_dbgeo.upper);
-    new_geo.grow = (uint16_t)bytes2pgno(env, env->me_dbgeo.grow);
-    new_geo.shrink = (uint16_t)bytes2pgno(env, env->me_dbgeo.shrink);
-    new_geo.next = current_geo->next;
-
-    mdbx_ensure(env,
-                pgno_align2os_bytes(env, new_geo.lower) == env->me_dbgeo.lower);
-    mdbx_ensure(env,
-                pgno_align2os_bytes(env, new_geo.upper) == env->me_dbgeo.upper);
-    mdbx_ensure(env,
-                pgno_align2os_bytes(env, new_geo.now) == env->me_dbgeo.now);
-    mdbx_ensure(env,
-                pgno_align2os_bytes(env, new_geo.grow) == env->me_dbgeo.grow);
-    mdbx_ensure(env, pgno_align2os_bytes(env, new_geo.shrink) ==
-                         env->me_dbgeo.shrink);
-
-    mdbx_ensure(env, env->me_dbgeo.lower >= MIN_MAPSIZE);
-    mdbx_ensure(env, new_geo.lower >= MIN_PAGENO);
-    mdbx_ensure(env, env->me_dbgeo.upper <= MAX_MAPSIZE);
-    mdbx_ensure(env, new_geo.upper <= MAX_PAGENO);
-    mdbx_ensure(env, new_geo.now >= new_geo.next);
-    mdbx_ensure(env, new_geo.upper >= new_geo.now);
-    mdbx_ensure(env, new_geo.now >= new_geo.lower);
-
-    if (memcmp(current_geo, &new_geo, sizeof(mdbx_geo_t)) != 0) {
-#if defined(_WIN32) || defined(_WIN64)
-      /* Was DB shrinking disabled before and now it will be enabled? */
-      if (new_geo.lower < new_geo.upper && new_geo.shrink &&
-          !(current_geo->lower < current_geo->upper && current_geo->shrink)) {
-        if (!env->me_lck) {
-          rc = MDBX_EPERM;
-          goto bailout;
-        }
-        int err = mdbx_rdt_lock(env);
-        if (unlikely(MDBX_IS_ERROR(err))) {
-          rc = err;
-          goto bailout;
-        }
-
-        /* Check if there are any reading threads that do not use the SRWL */
-        const size_t CurrentTid = GetCurrentThreadId();
-        const MDBX_reader *const begin = env->me_lck->mti_readers;
-        const MDBX_reader *const end =
-            begin +
-            atomic_load32(&env->me_lck->mti_numreaders, mo_AcquireRelease);
-        for (const MDBX_reader *reader = begin; reader < end; ++reader) {
-          if (reader->mr_pid.weak == env->me_pid && reader->mr_tid.weak &&
-              reader->mr_tid.weak != CurrentTid) {
-            /* At least one thread may don't use SRWL */
-            rc = MDBX_EPERM;
-            break;
-          }
-        }
-
-        mdbx_rdt_unlock(env);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      }
-#endif
-
-      if (new_geo.now != current_geo->now ||
-          new_geo.upper != current_geo->upper) {
-        rc = mdbx_mapresize(env, current_geo->next, new_geo.now, new_geo.upper,
-                            false);
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-        mdbx_assert(env, (head == nullptr) == inside_txn);
-        if (head)
-          head = /* base address could be changed */ mdbx_meta_head(env);
-      }
-      if (inside_txn) {
-        env->me_txn->mt_geo = new_geo;
-        env->me_txn->mt_flags |= MDBX_TXN_DIRTY;
-      } else {
-        meta.mm_geo = new_geo;
-        const txnid_t txnid =
-            safe64_txnid_next(mdbx_meta_txnid_stable(env, head));
-        if (unlikely(txnid > MAX_TXNID)) {
-          rc = MDBX_TXN_FULL;
-          mdbx_error("txnid overflow, raise %d", rc);
-          goto bailout;
-        }
-        mdbx_meta_set_txnid(env, &meta, txnid);
-        rc = mdbx_sync_locked(env, env->me_flags, &meta);
-      }
-    }
-  } else if (pagesize != (intptr_t)env->me_psize) {
-    mdbx_setup_pagesize(env, pagesize);
-  }
-
-bailout:
-  if (need_unlock)
-    mdbx_txn_unlock(env);
-  return rc;
-}
-
-__cold int mdbx_env_set_mapsize(MDBX_env *env, size_t size) {
-  return __inline_mdbx_env_set_mapsize(env, size);
-}
-
-__cold int mdbx_env_set_maxdbs(MDBX_env *env, MDBX_dbi dbs) {
-  return __inline_mdbx_env_set_maxdbs(env, dbs);
-}
-
-__cold int mdbx_env_get_maxdbs(const MDBX_env *env, MDBX_dbi *dbs) {
-  return __inline_mdbx_env_get_maxdbs(env, dbs);
-}
-
-__cold int mdbx_env_set_maxreaders(MDBX_env *env, unsigned readers) {
-  return __inline_mdbx_env_set_maxreaders(env, readers);
-}
-
-__cold int mdbx_env_get_maxreaders(const MDBX_env *env, unsigned *readers) {
-  return __inline_mdbx_env_get_maxreaders(env, readers);
-}
-
-/* Further setup required for opening an MDBX environment */
-static __cold int mdbx_setup_dxb(MDBX_env *env, const int lck_rc) {
-  uint64_t filesize_before;
-  MDBX_meta meta;
-  int rc = MDBX_RESULT_FALSE;
-  int err = mdbx_read_header(env, &meta, &filesize_before, lck_rc);
-  if (unlikely(err != MDBX_SUCCESS)) {
-    if (lck_rc != /* lck exclusive */ MDBX_RESULT_TRUE || err != MDBX_ENODATA ||
-        (env->me_flags & MDBX_RDONLY) != 0 ||
-        /* recovery mode */ env->me_stuck_meta >= 0)
-      return err;
-
-    mdbx_debug("%s", "create new database");
-    rc = /* new database */ MDBX_RESULT_TRUE;
-
-    if (!env->me_dbgeo.now) {
-      /* set defaults if not configured */
-      err = mdbx_env_set_geometry(env, 0, -1, DEFAULT_MAPSIZE, -1, -1, -1);
-      if (unlikely(err != MDBX_SUCCESS))
-        return err;
-    }
-
-    void *buffer = mdbx_calloc(NUM_METAS, env->me_psize);
-    if (!buffer)
-      return MDBX_ENOMEM;
-
-    meta = *mdbx_init_metas(env, buffer);
-    err = mdbx_pwrite(env->me_lazy_fd, buffer, env->me_psize * NUM_METAS, 0);
-    mdbx_free(buffer);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-
-    err = mdbx_ftruncate(env->me_lazy_fd, filesize_before = env->me_dbgeo.now);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-
-#ifndef NDEBUG /* just for checking */
-    err = mdbx_read_header(env, &meta, &filesize_before, lck_rc);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-#endif
-  }
-
-  mdbx_verbose("header: root %" PRIaPGNO "/%" PRIaPGNO ", geo %" PRIaPGNO
-               "/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
-               " +%u -%u, txn_id %" PRIaTXN ", %s",
-               meta.mm_dbs[MAIN_DBI].md_root, meta.mm_dbs[FREE_DBI].md_root,
-               meta.mm_geo.lower, meta.mm_geo.next, meta.mm_geo.now,
-               meta.mm_geo.upper, meta.mm_geo.grow, meta.mm_geo.shrink,
-               unaligned_peek_u64(4, meta.mm_txnid_a), mdbx_durable_str(&meta));
-
-  mdbx_setup_pagesize(env, meta.mm_psize);
-  const size_t used_bytes = pgno2bytes(env, meta.mm_geo.next);
-  const size_t used_aligned2os_bytes =
-      ceil_powerof2(used_bytes, env->me_os_psize);
-  if ((env->me_flags & MDBX_RDONLY) /* readonly */
-      || lck_rc != MDBX_RESULT_TRUE /* not exclusive */
-      || /* recovery mode */ env->me_stuck_meta >= 0) {
-    /* use present params from db */
-    const size_t pagesize = meta.mm_psize;
-    err = mdbx_env_set_geometry(
-        env, meta.mm_geo.lower * pagesize, meta.mm_geo.now * pagesize,
-        meta.mm_geo.upper * pagesize, meta.mm_geo.grow * pagesize,
-        meta.mm_geo.shrink * pagesize, meta.mm_psize);
-    if (unlikely(err != MDBX_SUCCESS)) {
-      mdbx_error("%s: err %d", "could not apply preconfigured geometry from db",
-                 err);
-      return (err == MDBX_EINVAL) ? MDBX_INCOMPATIBLE : err;
-    }
-  } else if (env->me_dbgeo.now) {
-    /* silently growth to last used page */
-    if (env->me_dbgeo.now < used_aligned2os_bytes)
-      env->me_dbgeo.now = used_aligned2os_bytes;
-    if (env->me_dbgeo.upper < used_aligned2os_bytes)
-      env->me_dbgeo.upper = used_aligned2os_bytes;
-
-    /* apply preconfigured params, but only if substantial changes:
-     *  - upper or lower limit changes
-     *  - shrink threshold or growth step
-     * But ignore change just a 'now/current' size. */
-    if (bytes_align2os_bytes(env, env->me_dbgeo.upper) !=
-            pgno2bytes(env, meta.mm_geo.upper) ||
-        bytes_align2os_bytes(env, env->me_dbgeo.lower) !=
-            pgno2bytes(env, meta.mm_geo.lower) ||
-        bytes_align2os_bytes(env, env->me_dbgeo.shrink) !=
-            pgno2bytes(env, meta.mm_geo.shrink) ||
-        bytes_align2os_bytes(env, env->me_dbgeo.grow) !=
-            pgno2bytes(env, meta.mm_geo.grow)) {
-
-      if (env->me_dbgeo.shrink && env->me_dbgeo.now > used_bytes)
-        /* pre-shrink if enabled */
-        env->me_dbgeo.now = used_bytes + env->me_dbgeo.shrink -
-                            used_bytes % env->me_dbgeo.shrink;
-
-      err = mdbx_env_set_geometry(env, env->me_dbgeo.lower, env->me_dbgeo.now,
-                                  env->me_dbgeo.upper, env->me_dbgeo.grow,
-                                  env->me_dbgeo.shrink, meta.mm_psize);
-      if (unlikely(err != MDBX_SUCCESS)) {
-        mdbx_error("%s: err %d", "could not apply preconfigured db-geometry",
-                   err);
-        return (err == MDBX_EINVAL) ? MDBX_INCOMPATIBLE : err;
-      }
-
-      /* update meta fields */
-      meta.mm_geo.now = bytes2pgno(env, env->me_dbgeo.now);
-      meta.mm_geo.lower = bytes2pgno(env, env->me_dbgeo.lower);
-      meta.mm_geo.upper = bytes2pgno(env, env->me_dbgeo.upper);
-      meta.mm_geo.grow = (uint16_t)bytes2pgno(env, env->me_dbgeo.grow);
-      meta.mm_geo.shrink = (uint16_t)bytes2pgno(env, env->me_dbgeo.shrink);
-
-      mdbx_verbose("amended: root %" PRIaPGNO "/%" PRIaPGNO ", geo %" PRIaPGNO
-                   "/%" PRIaPGNO "-%" PRIaPGNO "/%" PRIaPGNO
-                   " +%u -%u, txn_id %" PRIaTXN ", %s",
-                   meta.mm_dbs[MAIN_DBI].md_root, meta.mm_dbs[FREE_DBI].md_root,
-                   meta.mm_geo.lower, meta.mm_geo.next, meta.mm_geo.now,
-                   meta.mm_geo.upper, meta.mm_geo.grow, meta.mm_geo.shrink,
-                   unaligned_peek_u64(4, meta.mm_txnid_a),
-                   mdbx_durable_str(&meta));
-    } else {
-      /* fetch back 'now/current' size, since it was ignored during comparison
-       * and may differ. */
-      env->me_dbgeo.now = pgno_align2os_bytes(env, meta.mm_geo.now);
-    }
-    mdbx_ensure(env, meta.mm_geo.now >= meta.mm_geo.next);
-  } else {
-    /* geo-params are not pre-configured by user,
-     * get current values from the meta. */
-    env->me_dbgeo.now = pgno2bytes(env, meta.mm_geo.now);
-    env->me_dbgeo.lower = pgno2bytes(env, meta.mm_geo.lower);
-    env->me_dbgeo.upper = pgno2bytes(env, meta.mm_geo.upper);
-    env->me_dbgeo.grow = pgno2bytes(env, meta.mm_geo.grow);
-    env->me_dbgeo.shrink = pgno2bytes(env, meta.mm_geo.shrink);
-  }
-
-  mdbx_ensure(env,
-              pgno_align2os_bytes(env, meta.mm_geo.now) == env->me_dbgeo.now);
-  mdbx_ensure(env, env->me_dbgeo.now >= used_bytes);
-  if (unlikely(filesize_before != env->me_dbgeo.now)) {
-    if (lck_rc != /* lck exclusive */ MDBX_RESULT_TRUE) {
-      mdbx_verbose("filesize mismatch (expect %" PRIuPTR "b/%" PRIaPGNO
-                   "p, have %" PRIu64 "b/%" PRIaPGNO "p), "
-                   "assume other process working",
-                   env->me_dbgeo.now, bytes2pgno(env, env->me_dbgeo.now),
-                   filesize_before, bytes2pgno(env, (size_t)filesize_before));
-    } else {
-      mdbx_warning("filesize mismatch (expect %" PRIuSIZE "b/%" PRIaPGNO
-                   "p, have %" PRIu64 "b/%" PRIaPGNO "p)",
-                   env->me_dbgeo.now, bytes2pgno(env, env->me_dbgeo.now),
-                   filesize_before, bytes2pgno(env, (size_t)filesize_before));
-      if (filesize_before < used_bytes) {
-        mdbx_error("last-page beyond end-of-file (last %" PRIaPGNO
-                   ", have %" PRIaPGNO ")",
-                   meta.mm_geo.next, bytes2pgno(env, (size_t)filesize_before));
-        return MDBX_CORRUPTED;
-      }
-
-      if (env->me_flags & MDBX_RDONLY) {
-        if (filesize_before & (env->me_os_psize - 1)) {
-          mdbx_error("%s", "filesize should be rounded-up to system page");
-          return MDBX_WANNA_RECOVERY;
-        }
-        mdbx_warning("%s", "ignore filesize mismatch in readonly-mode");
-      } else {
-        mdbx_verbose("will resize datafile to %" PRIuSIZE " bytes, %" PRIaPGNO
-                     " pages",
-                     env->me_dbgeo.now, bytes2pgno(env, env->me_dbgeo.now));
-      }
-    }
-  }
-
-  mdbx_verbose("current boot-id %" PRIx64 "-%" PRIx64 " (%savailable)",
-               bootid.x, bootid.y, (bootid.x | bootid.y) ? "" : "not-");
-
-  /* calculate readahead hint before mmap with zero redundant pages */
-  const bool readahead =
-      (env->me_flags & MDBX_NORDAHEAD) == 0 &&
-      mdbx_is_readahead_reasonable(used_bytes, 0) == MDBX_RESULT_TRUE;
-  err = mdbx_mmap(env->me_flags, &env->me_dxb_mmap, env->me_dbgeo.now,
-                  env->me_dbgeo.upper, lck_rc ? MMAP_OPTION_TRUNCATE : 0);
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-
-#if defined(MADV_DONTDUMP)
-  err = madvise(env->me_map, env->me_dxb_mmap.limit, MADV_DONTDUMP)
-            ? ignore_enosys(errno)
-            : MDBX_SUCCESS;
-  if (unlikely(MDBX_IS_ERROR(err)))
-    return err;
-#endif /* MADV_DONTDUMP */
-#if defined(MADV_DODUMP)
-  if (mdbx_runtime_flags & MDBX_DBG_DUMP) {
-    const size_t meta_length_aligned2os = pgno_align2os_bytes(env, NUM_METAS);
-    err = madvise(env->me_map, meta_length_aligned2os, MADV_DODUMP)
-              ? ignore_enosys(errno)
-              : MDBX_SUCCESS;
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-  }
-#endif /* MADV_DODUMP */
-
-#ifdef MDBX_USE_VALGRIND
-  env->me_valgrind_handle =
-      VALGRIND_CREATE_BLOCK(env->me_map, env->me_dxb_mmap.limit, "mdbx");
-#endif /* MDBX_USE_VALGRIND */
-
-  mdbx_assert(env, used_bytes >= pgno2bytes(env, NUM_METAS) &&
-                       used_bytes <= env->me_dxb_mmap.limit);
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  VALGRIND_MAKE_MEM_NOACCESS(env->me_map + used_bytes,
-                             env->me_dxb_mmap.limit - used_bytes);
-  ASAN_POISON_MEMORY_REGION(env->me_map + used_bytes,
-                            env->me_dxb_mmap.limit - used_bytes);
-  env->me_poison_edge = bytes2pgno(env, env->me_dxb_mmap.limit);
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-
-  const unsigned meta_clash_mask = mdbx_meta_eq_mask(env);
-  if (unlikely(meta_clash_mask)) {
-    if (/* not recovery mode */ env->me_stuck_meta < 0) {
-      mdbx_error("meta-pages are clashed: mask 0x%d", meta_clash_mask);
-      return MDBX_CORRUPTED;
-    } else {
-      mdbx_warning("ignore meta-pages clashing (mask 0x%d) in recovery mode",
-                   meta_clash_mask);
-    }
-  }
-
-  while (likely(/* not recovery mode */ env->me_stuck_meta < 0)) {
-    MDBX_meta *const head = mdbx_meta_head(env);
-    const txnid_t head_txnid = mdbx_meta_txnid_fluid(env, head);
-    MDBX_meta *const steady = mdbx_meta_steady(env);
-    const txnid_t steady_txnid = mdbx_meta_txnid_fluid(env, steady);
-    if (head_txnid == steady_txnid)
-      break;
-
-    if (lck_rc == /* lck exclusive */ MDBX_RESULT_TRUE) {
-      mdbx_assert(env, META_IS_STEADY(steady) && !META_IS_STEADY(head));
-      if (meta_bootid_match(head)) {
-        MDBX_meta clone = *head;
-        uint64_t filesize = env->me_dbgeo.now;
-        err = mdbx_validate_meta(
-            env, &clone, &filesize, data_page(head),
-            bytes2pgno(env, (uint8_t *)data_page(head) - env->me_map), nullptr,
-            env->me_psize);
-        if (err == MDBX_SUCCESS) {
-          mdbx_warning(
-              "opening after an unclean shutdown, but boot-id(%016" PRIx64
-              "-%016" PRIx64
-              ") is MATCH: rollback NOT needed, steady-sync NEEDED%s",
-              bootid.x, bootid.y,
-              (env->me_flags & MDBX_RDONLY) ? ", but unable in read-only mode"
-                                            : "");
-          if (env->me_flags & MDBX_RDONLY)
-            return MDBX_WANNA_RECOVERY /* LY: could not recovery/sync */;
-          meta = clone;
-          atomic_store32(env->me_unsynced_pages, meta.mm_geo.next, mo_Relaxed);
-          break;
-        }
-        mdbx_warning("opening after an unclean shutdown, "
-                     "but boot-id(%016" PRIx64 "-%016" PRIx64 ") is MATCH, "
-                     "but last meta not valid, rollback needed",
-                     bootid.x, bootid.y);
-      }
-      if (env->me_flags & MDBX_RDONLY) {
-        mdbx_error("rollback needed: (from head %" PRIaTXN
-                   " to steady %" PRIaTXN "), but unable in read-only mode",
-                   head_txnid, steady_txnid);
-        return MDBX_WANNA_RECOVERY /* LY: could not recovery/rollback */;
-      }
-
-      const MDBX_meta *const meta0 = METAPAGE(env, 0);
-      const MDBX_meta *const meta1 = METAPAGE(env, 1);
-      const MDBX_meta *const meta2 = METAPAGE(env, 2);
-      txnid_t undo_txnid = 0 /* zero means undo is unneeded */;
-      while (
-          (head != meta0 && mdbx_meta_txnid_fluid(env, meta0) == undo_txnid) ||
-          (head != meta1 && mdbx_meta_txnid_fluid(env, meta1) == undo_txnid) ||
-          (head != meta2 && mdbx_meta_txnid_fluid(env, meta2) == undo_txnid))
-        undo_txnid = safe64_txnid_next(undo_txnid);
-      if (unlikely(undo_txnid >= steady_txnid)) {
-        mdbx_fatal("rollback failed: no suitable txnid (0,1,2) < %" PRIaTXN,
-                   steady_txnid);
-        return MDBX_PANIC /* LY: could not recovery/rollback */;
-      }
-
-      /* LY: rollback weak checkpoint */
-      mdbx_notice("rollback: from %" PRIaTXN ", to %" PRIaTXN " as %" PRIaTXN,
-                  head_txnid, steady_txnid, undo_txnid);
-      mdbx_ensure(env, head_txnid == mdbx_meta_txnid_stable(env, head));
-
-      if (env->me_flags & MDBX_WRITEMAP) {
-        /* It is possible to update txnid without safe64_write(),
-         * since DB opened exclusive for now */
-        unaligned_poke_u64(4, head->mm_txnid_a, undo_txnid);
-        unaligned_poke_u64(4, head->mm_datasync_sign, MDBX_DATASIGN_WEAK);
-        unaligned_poke_u64(4, head->mm_txnid_b, undo_txnid);
-        const size_t offset = (uint8_t *)data_page(head) - env->me_dxb_mmap.dxb;
-        const size_t paged_offset = floor_powerof2(offset, env->me_os_psize);
-        const size_t paged_length = ceil_powerof2(
-            env->me_psize + offset - paged_offset, env->me_os_psize);
-        err = mdbx_msync(&env->me_dxb_mmap, paged_offset, paged_length, false);
-      } else {
-        MDBX_meta rollback = *head;
-        mdbx_meta_set_txnid(env, &rollback, undo_txnid);
-        unaligned_poke_u64(4, rollback.mm_datasync_sign, MDBX_DATASIGN_WEAK);
-        err = mdbx_pwrite(env->me_lazy_fd, &rollback, sizeof(MDBX_meta),
-                          (uint8_t *)head - (uint8_t *)env->me_map);
-      }
-      if (err) {
-        mdbx_error("error %d rollback from %" PRIaTXN ", to %" PRIaTXN
-                   " as %" PRIaTXN,
-                   err, head_txnid, steady_txnid, undo_txnid);
-        return err;
-      }
-
-      mdbx_flush_incoherent_mmap(env->me_map, pgno2bytes(env, NUM_METAS),
-                                 env->me_os_psize);
-      mdbx_ensure(env, undo_txnid == mdbx_meta_txnid_fluid(env, head));
-      mdbx_ensure(env, 0 == mdbx_meta_eq_mask(env));
-      continue;
-    }
-
-    if (!env->me_lck) {
-      /* LY: without-lck (read-only) mode, so it is impossible that other
-       * process made weak checkpoint. */
-      mdbx_error("%s", "without-lck, unable recovery/rollback");
-      return MDBX_WANNA_RECOVERY;
-    }
-
-    /* LY: assume just have a collision with other running process,
-     *     or someone make a weak checkpoint */
-    mdbx_verbose("%s", "assume collision or online weak checkpoint");
-    break;
-  }
-
-  const MDBX_meta *head = mdbx_meta_head(env);
-  if (lck_rc == /* lck exclusive */ MDBX_RESULT_TRUE) {
-    /* re-check size after mmap */
-    if ((env->me_dxb_mmap.current & (env->me_os_psize - 1)) != 0 ||
-        env->me_dxb_mmap.current < used_bytes) {
-      mdbx_error("unacceptable/unexpected datafile size %" PRIuPTR,
-                 env->me_dxb_mmap.current);
-      return MDBX_PROBLEM;
-    }
-    if (env->me_dxb_mmap.current != env->me_dbgeo.now) {
-      meta.mm_geo.now = bytes2pgno(env, env->me_dxb_mmap.current);
-      mdbx_notice("need update meta-geo to filesize %" PRIuPTR
-                  " bytes, %" PRIaPGNO " pages",
-                  env->me_dxb_mmap.current, meta.mm_geo.now);
-    }
-
-    if (memcmp(&meta.mm_geo, &head->mm_geo, sizeof(meta.mm_geo))) {
-      if ((env->me_flags & MDBX_RDONLY) != 0 ||
-          /* recovery mode */ env->me_stuck_meta >= 0) {
-        mdbx_warning("skipped update meta.geo in %s mode: from l%" PRIaPGNO
-                     "-n%" PRIaPGNO "-u%" PRIaPGNO "/s%u-g%u, to l%" PRIaPGNO
-                     "-n%" PRIaPGNO "-u%" PRIaPGNO "/s%u-g%u",
-                     (env->me_stuck_meta < 0) ? "read-only" : "recovery",
-                     head->mm_geo.lower, head->mm_geo.now, head->mm_geo.upper,
-                     head->mm_geo.shrink, head->mm_geo.grow, meta.mm_geo.lower,
-                     meta.mm_geo.now, meta.mm_geo.upper, meta.mm_geo.shrink,
-                     meta.mm_geo.grow);
-      } else {
-        const txnid_t txnid = mdbx_meta_txnid_stable(env, head);
-        const txnid_t next_txnid = safe64_txnid_next(txnid);
-        if (unlikely(txnid > MAX_TXNID)) {
-          mdbx_error("txnid overflow, raise %d", MDBX_TXN_FULL);
-          return MDBX_TXN_FULL;
-        }
-        mdbx_notice("updating meta.geo: "
-                    "from l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
-                    "/s%u-g%u (txn#%" PRIaTXN "), "
-                    "to l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
-                    "/s%u-g%u (txn#%" PRIaTXN ")",
-                    head->mm_geo.lower, head->mm_geo.now, head->mm_geo.upper,
-                    head->mm_geo.shrink, head->mm_geo.grow, txnid,
-                    meta.mm_geo.lower, meta.mm_geo.now, meta.mm_geo.upper,
-                    meta.mm_geo.shrink, meta.mm_geo.grow, next_txnid);
-
-        mdbx_ensure(env, mdbx_meta_eq(env, &meta, head));
-        mdbx_meta_set_txnid(env, &meta, next_txnid);
-        err = mdbx_sync_locked(env, env->me_flags | MDBX_SHRINK_ALLOWED, &meta);
-        if (err) {
-          mdbx_error("error %d, while updating meta.geo: "
-                     "from l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
-                     "/s%u-g%u (txn#%" PRIaTXN "), "
-                     "to l%" PRIaPGNO "-n%" PRIaPGNO "-u%" PRIaPGNO
-                     "/s%u-g%u (txn#%" PRIaTXN ")",
-                     err, head->mm_geo.lower, head->mm_geo.now,
-                     head->mm_geo.upper, head->mm_geo.shrink, head->mm_geo.grow,
-                     txnid, meta.mm_geo.lower, meta.mm_geo.now,
-                     meta.mm_geo.upper, meta.mm_geo.shrink, meta.mm_geo.grow,
-                     next_txnid);
-          return err;
-        }
-      }
-    }
-  }
-
-  atomic_store32(env->me_discarded_tail, bytes2pgno(env, used_aligned2os_bytes),
-                 mo_AcquireRelease);
-  if (used_aligned2os_bytes < env->me_dxb_mmap.current) {
-#if defined(MADV_REMOVE)
-    if (lck_rc && (env->me_flags & MDBX_WRITEMAP) != 0 &&
-        /* not recovery mode */ env->me_stuck_meta < 0) {
-      mdbx_notice("open-MADV_%s %u..%u", "REMOVE (deallocate file space)",
-                  env->me_discarded_tail->weak,
-                  bytes2pgno(env, env->me_dxb_mmap.current));
-      err =
-          madvise(env->me_map + used_aligned2os_bytes,
-                  env->me_dxb_mmap.current - used_aligned2os_bytes, MADV_REMOVE)
-              ? ignore_enosys(errno)
-              : MDBX_SUCCESS;
-      if (unlikely(MDBX_IS_ERROR(err)))
-        return err;
-    }
-#endif /* MADV_REMOVE */
-#if defined(MADV_DONTNEED)
-    mdbx_notice("open-MADV_%s %u..%u", "DONTNEED", env->me_discarded_tail->weak,
-                bytes2pgno(env, env->me_dxb_mmap.current));
-    err =
-        madvise(env->me_map + used_aligned2os_bytes,
-                env->me_dxb_mmap.current - used_aligned2os_bytes, MADV_DONTNEED)
-            ? ignore_enosys(errno)
-            : MDBX_SUCCESS;
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#elif defined(POSIX_MADV_DONTNEED)
-    err = ignore_enosys(posix_madvise(
-        env->me_map + used_aligned2os_bytes,
-        env->me_dxb_mmap.current - used_aligned2os_bytes, POSIX_MADV_DONTNEED));
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#elif defined(POSIX_FADV_DONTNEED)
-    err = ignore_enosys(posix_fadvise(
-        env->me_lazy_fd, used_aligned2os_bytes,
-        env->me_dxb_mmap.current - used_aligned2os_bytes, POSIX_FADV_DONTNEED));
-    if (unlikely(MDBX_IS_ERROR(err)))
-      return err;
-#endif /* MADV_DONTNEED */
-  }
-
-  err = mdbx_set_readahead(env, 0, used_bytes, readahead);
-  if (err != MDBX_SUCCESS && lck_rc == /* lck exclusive */ MDBX_RESULT_TRUE)
-    return err;
-
-  return rc;
-}
-
-/******************************************************************************/
-
-/* Open and/or initialize the lock region for the environment. */
-static __cold int mdbx_setup_lck(MDBX_env *env, char *lck_pathname,
-                                 mdbx_mode_t mode) {
-  mdbx_assert(env, env->me_lazy_fd != INVALID_HANDLE_VALUE);
-  mdbx_assert(env, env->me_lfd == INVALID_HANDLE_VALUE);
-
-  int err = mdbx_openfile(MDBX_OPEN_LCK, env, lck_pathname, &env->me_lfd, mode);
-  if (err != MDBX_SUCCESS) {
-    if (!(err == MDBX_ENOFILE && (env->me_flags & MDBX_EXCLUSIVE)) &&
-        !((err == MDBX_EROFS || err == MDBX_EACCESS || err == MDBX_EPERM) &&
-          (env->me_flags & MDBX_RDONLY)))
-      return err;
-
-    /* ensure the file system is read-only */
-    err = mdbx_check_fs_rdonly(env->me_lazy_fd, lck_pathname, err);
-    if (err != MDBX_SUCCESS &&
-        /* ignore ERROR_NOT_SUPPORTED for exclusive mode */
-        !(err == MDBX_ENOSYS && (env->me_flags & MDBX_EXCLUSIVE)))
-      return err;
-
-    /* LY: without-lck mode (e.g. exclusive or on read-only filesystem) */
-    /* beginning of a locked section ---------------------------------------- */
-    lcklist_lock();
-    mdbx_assert(env, env->me_lcklist_next == nullptr);
-    env->me_lfd = INVALID_HANDLE_VALUE;
-    const int rc = mdbx_lck_seize(env);
-    if (MDBX_IS_ERROR(rc)) {
-      /* Calling lcklist_detach_locked() is required to restore POSIX-filelock
-       * and this job will be done by mdbx_env_close0(). */
-      lcklist_unlock();
-      return rc;
-    }
-    /* insert into inprocess lck-list */
-    env->me_lcklist_next = inprocess_lcklist_head;
-    inprocess_lcklist_head = env;
-    lcklist_unlock();
-    /* end of a locked section ---------------------------------------------- */
-
-    env->me_oldest = &env->me_lckless_stub.oldest;
-    env->me_sync_timestamp = &env->me_lckless_stub.sync_timestamp;
-    env->me_autosync_period = &env->me_lckless_stub.autosync_period;
-    env->me_unsynced_pages = &env->me_lckless_stub.autosync_pending;
-    env->me_autosync_threshold = &env->me_lckless_stub.autosync_threshold;
-    env->me_discarded_tail = &env->me_lckless_stub.discarded_tail;
-    env->me_meta_sync_txnid = &env->me_lckless_stub.meta_sync_txnid;
-    env->me_maxreaders = UINT_MAX;
-#if MDBX_LOCKING > 0
-    env->me_wlock = &env->me_lckless_stub.wlock;
-#endif /* MDBX_LOCKING > 0 */
-    mdbx_debug("lck-setup:%s%s%s", " lck-less",
-               (env->me_flags & MDBX_RDONLY) ? " readonly" : "",
-               (rc == MDBX_RESULT_TRUE) ? " exclusive" : " cooperative");
-    return rc;
-  }
-
-  /* beginning of a locked section ------------------------------------------ */
-  lcklist_lock();
-  mdbx_assert(env, env->me_lcklist_next == nullptr);
-
-  /* Try to get exclusive lock. If we succeed, then
-   * nobody is using the lock region and we should initialize it. */
-  err = mdbx_lck_seize(env);
-  if (MDBX_IS_ERROR(err)) {
-  bailout:
-    /* Calling lcklist_detach_locked() is required to restore POSIX-filelock
-     * and this job will be done by mdbx_env_close0(). */
-    lcklist_unlock();
-    return err;
-  }
-
-  MDBX_env *inprocess_neighbor = nullptr;
-  if (err == MDBX_RESULT_TRUE) {
-    err = uniq_check(&env->me_lck_mmap, &inprocess_neighbor);
-    if (MDBX_IS_ERROR(err))
-      goto bailout;
-    if (inprocess_neighbor &&
-        ((mdbx_runtime_flags & MDBX_DBG_LEGACY_MULTIOPEN) == 0 ||
-         (inprocess_neighbor->me_flags & MDBX_EXCLUSIVE) != 0)) {
-      err = MDBX_BUSY;
-      goto bailout;
-    }
-  }
-  const int lck_seize_rc = err;
-
-  mdbx_debug("lck-setup:%s%s%s", " with-lck",
-             (env->me_flags & MDBX_RDONLY) ? " readonly" : "",
-             (lck_seize_rc == MDBX_RESULT_TRUE) ? " exclusive"
-                                                : " cooperative");
-
-  uint64_t size = 0;
-  err = mdbx_filesize(env->me_lfd, &size);
-  if (unlikely(err != MDBX_SUCCESS))
-    goto bailout;
-
-  if (lck_seize_rc == MDBX_RESULT_TRUE) {
-    size = ceil_powerof2(env->me_maxreaders * sizeof(MDBX_reader) +
-                             sizeof(MDBX_lockinfo),
-                         env->me_os_psize);
-    mdbx_jitter4testing(false);
-  } else {
-    if (env->me_flags & MDBX_EXCLUSIVE) {
-      err = MDBX_BUSY;
-      goto bailout;
-    }
-    if (size > INT_MAX || (size & (env->me_os_psize - 1)) != 0 ||
-        size < env->me_os_psize) {
-      mdbx_error("lck-file has invalid size %" PRIu64 " bytes", size);
-      err = MDBX_PROBLEM;
-      goto bailout;
-    }
-  }
-
-  const size_t maxreaders =
-      ((size_t)size - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader);
-  if (maxreaders < 4) {
-    mdbx_error("lck-size too small (up to %" PRIuPTR " readers)", maxreaders);
-    err = MDBX_PROBLEM;
-    goto bailout;
-  }
-  env->me_maxreaders = (maxreaders <= MDBX_READERS_LIMIT)
-                           ? (unsigned)maxreaders
-                           : (unsigned)MDBX_READERS_LIMIT;
-
-  err = mdbx_mmap((env->me_flags & MDBX_EXCLUSIVE) | MDBX_WRITEMAP,
-                  &env->me_lck_mmap, (size_t)size, (size_t)size,
-                  lck_seize_rc ? MMAP_OPTION_TRUNCATE | MMAP_OPTION_SEMAPHORE
-                               : MMAP_OPTION_SEMAPHORE);
-  if (unlikely(err != MDBX_SUCCESS))
-    goto bailout;
-
-#ifdef MADV_DODUMP
-  err = madvise(env->me_lck, size, MADV_DODUMP) ? ignore_enosys(errno)
-                                                : MDBX_SUCCESS;
-  if (unlikely(MDBX_IS_ERROR(err)))
-    goto bailout;
-#endif /* MADV_DODUMP */
-
-#ifdef MADV_WILLNEED
-  err = madvise(env->me_lck, size, MADV_WILLNEED) ? ignore_enosys(errno)
-                                                  : MDBX_SUCCESS;
-  if (unlikely(MDBX_IS_ERROR(err)))
-    goto bailout;
-#endif /* MADV_WILLNEED */
-
-  struct MDBX_lockinfo *const lck = env->me_lck;
-  if (lck_seize_rc == MDBX_RESULT_TRUE) {
-    /* LY: exclusive mode, check and reset lck content */
-    memset(lck, 0, (size_t)size);
-    mdbx_jitter4testing(false);
-    lck->mti_magic_and_version = MDBX_LOCK_MAGIC;
-    lck->mti_os_and_format = MDBX_LOCK_FORMAT;
-    err = mdbx_msync(&env->me_lck_mmap, 0, (size_t)size, false);
-    if (unlikely(err != MDBX_SUCCESS)) {
-      mdbx_error("initial-%s for lck-file failed", "msync");
-      goto bailout;
-    }
-    err = mdbx_fsync(env->me_lck_mmap.fd, MDBX_SYNC_SIZE);
-    if (unlikely(err != MDBX_SUCCESS)) {
-      mdbx_error("initial-%s for lck-file failed", "fsync");
-      goto bailout;
-    }
-  } else {
-    if (lck->mti_magic_and_version != MDBX_LOCK_MAGIC) {
-      mdbx_error("%s", "lock region has invalid magic/version");
-      err = ((lck->mti_magic_and_version >> 8) != MDBX_MAGIC)
-                ? MDBX_INVALID
-                : MDBX_VERSION_MISMATCH;
-      goto bailout;
-    }
-    if (lck->mti_os_and_format != MDBX_LOCK_FORMAT) {
-      mdbx_error("lock region has os/format 0x%" PRIx32 ", expected 0x%" PRIx32,
-                 lck->mti_os_and_format, MDBX_LOCK_FORMAT);
-      err = MDBX_VERSION_MISMATCH;
-      goto bailout;
-    }
-  }
-
-  err = mdbx_lck_init(env, inprocess_neighbor, lck_seize_rc);
-  if (MDBX_IS_ERROR(err))
-    goto bailout;
-
-  mdbx_ensure(env, env->me_lcklist_next == nullptr);
-  /* insert into inprocess lck-list */
-  env->me_lcklist_next = inprocess_lcklist_head;
-  inprocess_lcklist_head = env;
-  lcklist_unlock();
-  /* end of a locked section ------------------------------------------------ */
-
-  mdbx_assert(env, !MDBX_IS_ERROR(lck_seize_rc));
-  env->me_oldest = &lck->mti_oldest_reader;
-  env->me_sync_timestamp = &lck->mti_sync_timestamp;
-  env->me_autosync_period = &lck->mti_autosync_period;
-  env->me_unsynced_pages = &lck->mti_unsynced_pages;
-  env->me_autosync_threshold = &lck->mti_autosync_threshold;
-  env->me_discarded_tail = &lck->mti_discarded_tail;
-  env->me_meta_sync_txnid = &lck->mti_meta_sync_txnid;
-#if MDBX_LOCKING > 0
-  env->me_wlock = &lck->mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-  return lck_seize_rc;
-}
-
-__cold int mdbx_is_readahead_reasonable(size_t volume, intptr_t redundancy) {
-  if (volume <= 1024 * 1024 * 4ul)
-    return MDBX_RESULT_TRUE;
-
-  const intptr_t pagesize = mdbx_syspagesize();
-  if (unlikely(pagesize < MIN_PAGESIZE || !is_powerof2(pagesize)))
-    return MDBX_INCOMPATIBLE;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MEMORYSTATUSEX info;
-  memset(&info, 0, sizeof(info));
-  info.dwLength = sizeof(info);
-  if (!GlobalMemoryStatusEx(&info))
-    return GetLastError();
-#endif
-  const int log2page = log2n(pagesize);
-
-#if defined(_WIN32) || defined(_WIN64)
-  const intptr_t total_ram_pages = (intptr_t)(info.ullTotalPhys >> log2page);
-#elif defined(_SC_PHYS_PAGES)
-  const intptr_t total_ram_pages = sysconf(_SC_PHYS_PAGES);
-  if (total_ram_pages == -1)
-    return errno;
-#elif defined(_SC_AIX_REALMEM)
-  const intptr_t total_ram_Kb = sysconf(_SC_AIX_REALMEM);
-  if (total_ram_Kb == -1)
-    return errno;
-  const intptr_t total_ram_pages = (total_ram_Kb << 10) >> log2page;
-#elif defined(HW_USERMEM) || defined(HW_PHYSMEM64) || defined(HW_MEMSIZE) ||   \
-    defined(HW_PHYSMEM)
-  size_t ram, len = sizeof(ram);
-  static const int mib[] = {
-    CTL_HW,
-#if defined(HW_USERMEM)
-    HW_USERMEM
-#elif defined(HW_PHYSMEM64)
-    HW_PHYSMEM64
-#elif defined(HW_MEMSIZE)
-    HW_MEMSIZE
-#else
-    HW_PHYSMEM
-#endif
-  };
-  if (sysctl(
-#ifdef SYSCTL_LEGACY_NONCONST_MIB
-          (int *)
-#endif
-              mib,
-          ARRAY_LENGTH(mib), &ram, &len, NULL, 0) != 0)
-    return errno;
-  if (len != sizeof(ram))
-    return MDBX_ENOSYS;
-  const intptr_t total_ram_pages = (intptr_t)(ram >> log2page);
-#else
-#error "FIXME: Get User-accessible or physical RAM"
-#endif
-  if (total_ram_pages < 1)
-    return MDBX_ENOSYS;
-
-  const intptr_t volume_pages = (volume + pagesize - 1) >> log2page;
-  const intptr_t redundancy_pages =
-      (redundancy < 0) ? -(intptr_t)((-redundancy + pagesize - 1) >> log2page)
-                       : (intptr_t)(redundancy + pagesize - 1) >> log2page;
-  if (volume_pages >= total_ram_pages ||
-      volume_pages + redundancy_pages >= total_ram_pages)
-    return MDBX_RESULT_FALSE;
-
-#if defined(_WIN32) || defined(_WIN64)
-  const intptr_t avail_ram_pages = (intptr_t)(info.ullAvailPhys >> log2page);
-#elif defined(_SC_AVPHYS_PAGES)
-  const intptr_t avail_ram_pages = sysconf(_SC_AVPHYS_PAGES);
-  if (avail_ram_pages == -1)
-    return errno;
-#elif defined(__MACH__)
-  mach_msg_type_number_t count = HOST_VM_INFO_COUNT;
-  vm_statistics_data_t vmstat;
-  mach_port_t mport = mach_host_self();
-  kern_return_t kerr = host_statistics(mach_host_self(), HOST_VM_INFO,
-                                       (host_info_t)&vmstat, &count);
-  mach_port_deallocate(mach_task_self(), mport);
-  if (unlikely(kerr != KERN_SUCCESS))
-    return MDBX_ENOSYS;
-  const intptr_t avail_ram_pages = vmstat.free_count;
-#elif defined(VM_TOTAL) || defined(VM_METER)
-  struct vmtotal info;
-  size_t len = sizeof(info);
-  static const int mib[] = {
-    CTL_VM,
-#if defined(VM_TOTAL)
-    VM_TOTAL
-#elif defined(VM_METER)
-    VM_METER
-#endif
-  };
-  if (sysctl(
-#ifdef SYSCTL_LEGACY_NONCONST_MIB
-          (int *)
-#endif
-              mib,
-          ARRAY_LENGTH(mib), &info, &len, NULL, 0) != 0)
-    return errno;
-  if (len != sizeof(info))
-    return MDBX_ENOSYS;
-  const intptr_t avail_ram_pages = info.t_free;
-#else
-#error "FIXME: Get Available RAM"
-#endif
-  if (avail_ram_pages < 1)
-    return MDBX_ENOSYS;
-
-  return (volume_pages + redundancy_pages >= avail_ram_pages)
-             ? MDBX_RESULT_FALSE
-             : MDBX_RESULT_TRUE;
-}
-
-/* Merge sync flags */
-static uint32_t merge_sync_flags(const uint32_t a, const uint32_t b) {
-  uint32_t r = a | b;
-
-  /* avoid false MDBX_UTTERLY_NOSYNC */
-  if (F_ISSET(r, MDBX_UTTERLY_NOSYNC) && !F_ISSET(a, MDBX_UTTERLY_NOSYNC) &&
-      !F_ISSET(b, MDBX_UTTERLY_NOSYNC))
-    r = (r - MDBX_UTTERLY_NOSYNC) | MDBX_SAFE_NOSYNC;
-
-  /* convert MDBX_DEPRECATED_MAPASYNC to MDBX_SAFE_NOSYNC */
-  if ((r & (MDBX_WRITEMAP | MDBX_DEPRECATED_MAPASYNC)) ==
-          (MDBX_WRITEMAP | MDBX_DEPRECATED_MAPASYNC) &&
-      !F_ISSET(r, MDBX_UTTERLY_NOSYNC))
-    r = (r - MDBX_DEPRECATED_MAPASYNC) | MDBX_SAFE_NOSYNC;
-
-  /* force MDBX_NOMETASYNC if MDBX_SAFE_NOSYNC enabled */
-  if (r & MDBX_SAFE_NOSYNC)
-    r |= MDBX_NOMETASYNC;
-
-  assert(!(F_ISSET(r, MDBX_UTTERLY_NOSYNC) &&
-           !F_ISSET(a, MDBX_UTTERLY_NOSYNC) &&
-           !F_ISSET(b, MDBX_UTTERLY_NOSYNC)));
-  return r;
-}
-
-__cold int mdbx_env_turn_for_recovery(MDBX_env *env, unsigned target_meta) {
-  if (unlikely(target_meta >= NUM_METAS))
-    return MDBX_EINVAL;
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if ((env->me_flags & (MDBX_EXCLUSIVE | MDBX_RDONLY)) != MDBX_EXCLUSIVE)
-    return MDBX_EPERM;
-
-  MDBX_page *page =
-      (env->me_flags & MDBX_WRITEMAP)
-          ? pgno2page(env, target_meta)
-          : memcpy(env->me_pbuf, pgno2page(env, target_meta), env->me_psize);
-  page->mp_pgno = target_meta;
-  page->mp_flags = P_META;
-
-  MDBX_meta *meta = page_meta(page);
-  unaligned_poke_u64(4, meta->mm_magic_and_version, MDBX_DATA_MAGIC);
-  meta->mm_psize = env->me_psize;
-  txnid_t txnid = mdbx_meta_txnid_stable(env, meta);
-  const txnid_t txnid0 = mdbx_meta_txnid_stable(env, METAPAGE(env, 0));
-  if (target_meta != 0 && txnid <= txnid0)
-    txnid = safe64_txnid_next(txnid0);
-  const txnid_t txnid1 = mdbx_meta_txnid_stable(env, METAPAGE(env, 1));
-  if (target_meta != 1 && txnid <= txnid1)
-    txnid = safe64_txnid_next(txnid1);
-  const txnid_t txnid2 = mdbx_meta_txnid_stable(env, METAPAGE(env, 2));
-  if (target_meta != 2 && txnid <= txnid2)
-    txnid = safe64_txnid_next(txnid2);
-
-  if (!META_IS_STEADY(meta) || mdbx_recent_committed_txnid(env) != txnid) {
-    if (unlikely(txnid > MAX_TXNID)) {
-      mdbx_error("txnid overflow, raise %d", MDBX_TXN_FULL);
-      return MDBX_TXN_FULL;
-    }
-    mdbx_meta_set_txnid(env, meta, txnid);
-    unaligned_poke_u64(4, meta->mm_datasync_sign, mdbx_meta_sign(meta));
-  }
-
-  if (env->me_flags & MDBX_WRITEMAP) {
-    mdbx_flush_incoherent_cpu_writeback();
-    rc = mdbx_msync(&env->me_dxb_mmap, 0, pgno_align2os_bytes(env, target_meta),
-                    MDBX_SYNC_DATA | MDBX_SYNC_IODQ);
-  } else {
-    const mdbx_filehandle_t fd = (env->me_dsync_fd != INVALID_HANDLE_VALUE)
-                                     ? env->me_dsync_fd
-                                     : env->me_lazy_fd;
-    rc = mdbx_pwrite(fd, page, env->me_psize, pgno2bytes(env, target_meta));
-    if (rc == MDBX_SUCCESS && fd == env->me_lazy_fd)
-      rc = mdbx_fsync(env->me_lazy_fd, MDBX_SYNC_DATA | MDBX_SYNC_IODQ);
-  }
-
-  return rc;
-}
-
-__cold int mdbx_env_open_for_recovery(MDBX_env *env, const char *pathname,
-                                      unsigned target_meta, bool writeable) {
-  if (unlikely(target_meta >= NUM_METAS))
-    return MDBX_EINVAL;
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  env->me_stuck_meta = (int8_t)target_meta;
-  return mdbx_env_open(
-      env, pathname, writeable ? MDBX_EXCLUSIVE : MDBX_EXCLUSIVE | MDBX_RDONLY,
-      0);
-}
-
-typedef struct {
-  void *buffer_for_free;
-  char *lck, *dxb;
-  size_t ent_len;
-} MDBX_handle_env_pathname;
-
-__cold static int mdbx_handle_env_pathname(MDBX_handle_env_pathname *ctx,
-                                           const char *pathname,
-                                           MDBX_env_flags_t *flags,
-                                           const mdbx_mode_t mode) {
-  int rc;
-  memset(ctx, 0, sizeof(*ctx));
-  if (unlikely(!pathname))
-    return MDBX_EINVAL;
-
-#if defined(_WIN32) || defined(_WIN64)
-  const size_t wlen = mbstowcs(nullptr, pathname, INT_MAX);
-  if (wlen < 1 || wlen > /* MAX_PATH */ INT16_MAX)
-    return ERROR_INVALID_NAME;
-  wchar_t *const pathnameW = _alloca((wlen + 1) * sizeof(wchar_t));
-  if (wlen != mbstowcs(pathnameW, pathname, wlen + 1))
-    return ERROR_INVALID_NAME;
-
-  const DWORD dwAttrib = GetFileAttributesW(pathnameW);
-  if (dwAttrib == INVALID_FILE_ATTRIBUTES) {
-    rc = GetLastError();
-    if (rc != MDBX_ENOFILE)
-      return rc;
-    if (mode == 0 || (*flags & MDBX_RDONLY) != 0)
-      /* can't open existing */
-      return rc;
-
-    /* auto-create directory if requested */
-    if ((*flags & MDBX_NOSUBDIR) == 0 &&
-        !CreateDirectoryW(pathnameW, nullptr)) {
-      rc = GetLastError();
-      if (rc != ERROR_ALREADY_EXISTS)
-        return rc;
-    }
-  } else {
-    /* ignore passed MDBX_NOSUBDIR flag and set it automatically */
-    *flags |= MDBX_NOSUBDIR;
-    if (dwAttrib & FILE_ATTRIBUTE_DIRECTORY)
-      *flags -= MDBX_NOSUBDIR;
-  }
-#else
-  struct stat st;
-  if (stat(pathname, &st)) {
-    rc = errno;
-    if (rc != MDBX_ENOFILE)
-      return rc;
-    if (mode == 0 || (*flags & MDBX_RDONLY) != 0)
-      /* can't open existing */
-      return rc;
-
-    /* auto-create directory if requested */
-    const mdbx_mode_t dir_mode =
-        (/* inherit read/write permissions for group and others */ mode &
-         (S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) |
-        /* always add read/write/search for owner */ S_IRWXU |
-        ((mode & S_IRGRP) ? /* +search if readable by group */ S_IXGRP : 0) |
-        ((mode & S_IROTH) ? /* +search if readable by others */ S_IXOTH : 0);
-    if ((*flags & MDBX_NOSUBDIR) == 0 && mkdir(pathname, dir_mode)) {
-      rc = errno;
-      if (rc != EEXIST)
-        return rc;
-    }
-  } else {
-    /* ignore passed MDBX_NOSUBDIR flag and set it automatically */
-    *flags |= MDBX_NOSUBDIR;
-    if (S_ISDIR(st.st_mode))
-      *flags -= MDBX_NOSUBDIR;
-  }
-#endif
-
-  static const char dxb_name[] = MDBX_DATANAME;
-  static const size_t dxb_name_len = sizeof(dxb_name) - 1;
-  static const char lck_name[] = MDBX_LOCKNAME;
-  static const char lock_suffix[] = MDBX_LOCK_SUFFIX;
-
-  ctx->ent_len = strlen(pathname);
-  if ((*flags & MDBX_NOSUBDIR) && ctx->ent_len >= dxb_name_len &&
-      !memcmp(dxb_name, pathname + ctx->ent_len - dxb_name_len, dxb_name_len)) {
-    *flags -= MDBX_NOSUBDIR;
-    ctx->ent_len -= dxb_name_len;
-  }
-
-  const size_t bytes_needed =
-      ctx->ent_len * 2 + ((*flags & MDBX_NOSUBDIR)
-                              ? sizeof(lock_suffix) + 1
-                              : sizeof(lck_name) + sizeof(dxb_name));
-  ctx->buffer_for_free = mdbx_malloc(bytes_needed);
-  if (!ctx->buffer_for_free)
-    return MDBX_ENOMEM;
-
-  ctx->lck = ctx->buffer_for_free;
-  if (*flags & MDBX_NOSUBDIR) {
-    ctx->dxb = ctx->lck + ctx->ent_len + sizeof(lock_suffix);
-    sprintf(ctx->lck, "%s%s", pathname, lock_suffix);
-    strcpy(ctx->dxb, pathname);
-  } else {
-    ctx->dxb = ctx->lck + ctx->ent_len + sizeof(lck_name);
-    sprintf(ctx->lck, "%.*s%s", (int)ctx->ent_len, pathname, lck_name);
-    sprintf(ctx->dxb, "%.*s%s", (int)ctx->ent_len, pathname, dxb_name);
-  }
-
-  return MDBX_SUCCESS;
-}
-
-__cold int mdbx_env_delete(const char *pathname, MDBX_env_delete_mode_t mode) {
-  switch (mode) {
-  default:
-    return MDBX_EINVAL;
-  case MDBX_ENV_JUST_DELETE:
-  case MDBX_ENV_ENSURE_UNUSED:
-  case MDBX_ENV_WAIT_FOR_UNUSED:
-    break;
-  }
-
-  MDBX_env dummy_env;
-  memset(&dummy_env, 0, sizeof(dummy_env));
-  dummy_env.me_flags =
-      (mode == MDBX_ENV_ENSURE_UNUSED) ? MDBX_EXCLUSIVE : MDBX_ENV_DEFAULTS;
-  dummy_env.me_os_psize = (unsigned)mdbx_syspagesize();
-  dummy_env.me_psize = (unsigned)mdbx_default_pagesize();
-  dummy_env.me_pathname = (char *)pathname;
-
-  MDBX_handle_env_pathname env_pathname;
-  STATIC_ASSERT(sizeof(dummy_env.me_flags) == sizeof(MDBX_env_flags_t));
-  int rc = MDBX_RESULT_TRUE,
-      err = mdbx_handle_env_pathname(
-          &env_pathname, pathname, (MDBX_env_flags_t *)&dummy_env.me_flags, 0);
-  if (likely(err == MDBX_SUCCESS)) {
-    mdbx_filehandle_t clk_handle = INVALID_HANDLE_VALUE,
-                      dxb_handle = INVALID_HANDLE_VALUE;
-    if (mode > MDBX_ENV_JUST_DELETE) {
-      err = mdbx_openfile(MDBX_OPEN_DELETE, &dummy_env, env_pathname.dxb,
-                          &dxb_handle, 0);
-      err = (err == MDBX_ENOFILE) ? MDBX_SUCCESS : err;
-      if (err == MDBX_SUCCESS) {
-        err = mdbx_openfile(MDBX_OPEN_DELETE, &dummy_env, env_pathname.lck,
-                            &clk_handle, 0);
-        err = (err == MDBX_ENOFILE) ? MDBX_SUCCESS : err;
-      }
-      if (err == MDBX_SUCCESS && clk_handle != INVALID_HANDLE_VALUE)
-        err = mdbx_lockfile(clk_handle, mode == MDBX_ENV_WAIT_FOR_UNUSED);
-      if (err == MDBX_SUCCESS && dxb_handle != INVALID_HANDLE_VALUE)
-        err = mdbx_lockfile(dxb_handle, mode == MDBX_ENV_WAIT_FOR_UNUSED);
-    }
-
-    if (err == MDBX_SUCCESS) {
-      err = mdbx_removefile(env_pathname.dxb);
-      if (err == MDBX_SUCCESS)
-        rc = MDBX_SUCCESS;
-      else if (err == MDBX_ENOFILE)
-        err = MDBX_SUCCESS;
-    }
-
-    if (err == MDBX_SUCCESS) {
-      err = mdbx_removefile(env_pathname.lck);
-      if (err == MDBX_SUCCESS)
-        rc = MDBX_SUCCESS;
-      else if (err == MDBX_ENOFILE)
-        err = MDBX_SUCCESS;
-    }
-
-    if (err == MDBX_SUCCESS && !(dummy_env.me_flags & MDBX_NOSUBDIR)) {
-      err = mdbx_removedirectory(pathname);
-      if (err == MDBX_SUCCESS)
-        rc = MDBX_SUCCESS;
-      else if (err == MDBX_ENOFILE)
-        err = MDBX_SUCCESS;
-    }
-
-    if (dxb_handle != INVALID_HANDLE_VALUE)
-      mdbx_closefile(dxb_handle);
-    if (clk_handle != INVALID_HANDLE_VALUE)
-      mdbx_closefile(clk_handle);
-  } else if (err == MDBX_ENOFILE)
-    err = MDBX_SUCCESS;
-
-  mdbx_free(env_pathname.buffer_for_free);
-  return (err == MDBX_SUCCESS) ? rc : err;
-}
-
-__cold int mdbx_env_open(MDBX_env *env, const char *pathname,
-                         MDBX_env_flags_t flags, mdbx_mode_t mode) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (flags & ~ENV_USABLE_FLAGS)
-    return MDBX_EINVAL;
-
-  if (env->me_lazy_fd != INVALID_HANDLE_VALUE ||
-      (env->me_flags & MDBX_ENV_ACTIVE) != 0)
-    return MDBX_EPERM;
-
-  /* pickup previously mdbx_env_set_flags(),
-   * but avoid MDBX_UTTERLY_NOSYNC by disjunction */
-  const uint32_t saved_me_flags = env->me_flags;
-  flags = merge_sync_flags(flags, env->me_flags);
-
-  MDBX_handle_env_pathname env_pathname;
-  rc = mdbx_handle_env_pathname(&env_pathname, pathname, &flags, mode);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto bailout;
-
-  if (flags & MDBX_RDONLY) {
-    /* LY: silently ignore irrelevant flags when
-     * we're only getting read access */
-    flags &= ~(MDBX_WRITEMAP | MDBX_DEPRECATED_MAPASYNC | MDBX_SAFE_NOSYNC |
-               MDBX_NOMETASYNC | MDBX_COALESCE | MDBX_LIFORECLAIM |
-               MDBX_NOMEMINIT | MDBX_ACCEDE);
-  } else {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-    /* Temporary `workaround` for OpenBSD kernel's flaw.
-     * See https://github.com/erthink/libmdbx/issues/67 */
-    if ((flags & MDBX_WRITEMAP) == 0) {
-      if (flags & MDBX_ACCEDE)
-        flags |= MDBX_WRITEMAP;
-      else {
-        mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__,
-                       "System (i.e. OpenBSD) requires MDBX_WRITEMAP because "
-                       "of an internal flaw(s) in a file/buffer/page cache.\n");
-        rc = 42 /* ENOPROTOOPT */;
-        goto bailout;
-      }
-    }
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-  }
-
-  env->me_flags = (flags & ~MDBX_FATAL_ERROR) | MDBX_ENV_ACTIVE;
-  env->me_pathname = mdbx_calloc(env_pathname.ent_len + 1, 1);
-  env->me_dbxs = mdbx_calloc(env->me_maxdbs, sizeof(MDBX_dbx));
-  env->me_dbflags = mdbx_calloc(env->me_maxdbs, sizeof(env->me_dbflags[0]));
-  env->me_dbiseqs = mdbx_calloc(env->me_maxdbs, sizeof(env->me_dbiseqs[0]));
-  if (!(env->me_dbxs && env->me_pathname && env->me_dbflags &&
-        env->me_dbiseqs)) {
-    rc = MDBX_ENOMEM;
-    goto bailout;
-  }
-  memcpy(env->me_pathname, env_pathname.dxb, env_pathname.ent_len);
-  env->me_dbxs[FREE_DBI].md_cmp = cmp_int_align4; /* aligned MDBX_INTEGERKEY */
-  env->me_dbxs[FREE_DBI].md_dcmp = cmp_lenfast;
-
-  rc = mdbx_openfile(F_ISSET(flags, MDBX_RDONLY) ? MDBX_OPEN_DXB_READ
-                                                 : MDBX_OPEN_DXB_LAZY,
-                     env, env_pathname.dxb, &env->me_lazy_fd, mode);
-  if (rc != MDBX_SUCCESS)
-    goto bailout;
-
-  mdbx_assert(env, env->me_dsync_fd == INVALID_HANDLE_VALUE);
-  if ((flags & (MDBX_RDONLY | MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC)) == 0) {
-    rc = mdbx_openfile(MDBX_OPEN_DXB_DSYNC, env, env_pathname.dxb,
-                       &env->me_dsync_fd, 0);
-    mdbx_ensure(env, (rc != MDBX_SUCCESS) ==
-                         (env->me_dsync_fd == INVALID_HANDLE_VALUE));
-  }
-
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  env->me_sysv_ipc.key = ftok(env_pathname.dxb, 42);
-  if (env->me_sysv_ipc.key == -1) {
-    rc = errno;
-    goto bailout;
-  }
-#endif /* MDBX_LOCKING */
-
-#if !(defined(_WIN32) || defined(_WIN64))
-  if (mode == 0) {
-    /* pickup mode for lck-file */
-    struct stat st;
-    if (fstat(env->me_lazy_fd, &st)) {
-      rc = errno;
-      goto bailout;
-    }
-    mode = st.st_mode;
-  }
-  mode = (/* inherit read permissions for group and others */ mode &
-          (S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) |
-         /* always add read/write/search for owner */ S_IRUSR | S_IWUSR |
-         ((mode & S_IRGRP) ? /* +write if readable by group */ S_IWGRP : 0) |
-         ((mode & S_IROTH) ? /* +write if readable by others */ S_IWOTH : 0);
-#endif /* !Windows */
-  const int lck_rc = mdbx_setup_lck(env, env_pathname.lck, mode);
-  if (MDBX_IS_ERROR(lck_rc)) {
-    rc = lck_rc;
-    goto bailout;
-  }
-
-  /* Set the position in files outside of the data to avoid corruption
-   * due to erroneous use of file descriptors in the application code. */
-  mdbx_fseek(env->me_lfd, UINT64_C(1) << 63);
-  mdbx_fseek(env->me_lazy_fd, UINT64_C(1) << 63);
-  if (env->me_dsync_fd != INVALID_HANDLE_VALUE)
-    mdbx_fseek(env->me_dsync_fd, UINT64_C(1) << 63);
-
-  const MDBX_env_flags_t rigorous_flags =
-      MDBX_SAFE_NOSYNC | MDBX_DEPRECATED_MAPASYNC;
-  const MDBX_env_flags_t mode_flags = rigorous_flags | MDBX_NOMETASYNC |
-                                      MDBX_LIFORECLAIM | MDBX_COALESCE |
-                                      MDBX_NORDAHEAD;
-
-  if (env->me_lck && lck_rc != MDBX_RESULT_TRUE &&
-      (env->me_flags & MDBX_RDONLY) == 0) {
-    while (atomic_load32(&env->me_lck->mti_envmode, mo_AcquireRelease) ==
-           MDBX_RDONLY) {
-      if (atomic_cas32(&env->me_lck->mti_envmode, MDBX_RDONLY,
-                       env->me_flags & mode_flags))
-        break;
-      atomic_yield();
-    }
-
-    if (env->me_flags & MDBX_ACCEDE) {
-      /* pickup current mode-flags, including MDBX_LIFORECLAIM |
-       * MDBX_COALESCE | MDBX_NORDAHEAD */
-      const unsigned diff =
-          (env->me_lck->mti_envmode.weak ^ env->me_flags) & mode_flags;
-      mdbx_notice("accede mode-flags: 0x%X, 0x%X -> 0x%X", diff, env->me_flags,
-                  env->me_flags ^ diff);
-      env->me_flags ^= diff;
-    }
-
-    if ((env->me_lck->mti_envmode.weak ^ env->me_flags) & rigorous_flags) {
-      mdbx_error("%s", "current mode/flags incompatible with requested");
-      rc = MDBX_INCOMPATIBLE;
-      goto bailout;
-    }
-  }
-
-  const int dxb_rc = mdbx_setup_dxb(env, lck_rc);
-  if (MDBX_IS_ERROR(dxb_rc)) {
-    rc = dxb_rc;
-    goto bailout;
-  }
-
-  if (unlikely(/* recovery mode */ env->me_stuck_meta >= 0) &&
-      (lck_rc != /* exclusive */ MDBX_RESULT_TRUE ||
-       (flags & MDBX_EXCLUSIVE) == 0)) {
-    mdbx_error("%s", "recovery requires exclusive mode");
-    rc = MDBX_BUSY;
-    goto bailout;
-  }
-
-  mdbx_debug("opened dbenv %p", (void *)env);
-  if (env->me_lck) {
-    if (lck_rc == MDBX_RESULT_TRUE) {
-      env->me_lck->mti_envmode.weak =
-          env->me_flags & (mode_flags | MDBX_RDONLY);
-      rc = mdbx_lck_downgrade(env);
-      mdbx_debug("lck-downgrade-%s: rc %i",
-                 (env->me_flags & MDBX_EXCLUSIVE) ? "partial" : "full", rc);
-      if (rc != MDBX_SUCCESS)
-        goto bailout;
-    } else {
-      rc = mdbx_cleanup_dead_readers(env, false, NULL);
-      if (MDBX_IS_ERROR(rc))
-        goto bailout;
-    }
-
-    if ((env->me_flags & MDBX_NOTLS) == 0) {
-      rc = mdbx_rthc_alloc(&env->me_txkey, &env->me_lck->mti_readers[0],
-                           &env->me_lck->mti_readers[env->me_maxreaders]);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto bailout;
-      env->me_flags |= MDBX_ENV_TXKEY;
-    }
-  }
-
-  if ((flags & MDBX_RDONLY) == 0) {
-    const size_t tsize = sizeof(MDBX_txn),
-                 size = tsize + env->me_maxdbs *
-                                    (sizeof(MDBX_db) + sizeof(MDBX_cursor *) +
-                                     sizeof(unsigned) + 1);
-    rc = mdbx_memalign_alloc(
-        env->me_os_psize,
-        env->me_psize * (1 /* page buffer */ + 1 /* page killer buffer */),
-        &env->me_pbuf);
-    if (rc == MDBX_SUCCESS) {
-      memset(env->me_pbuf, -1, env->me_psize * 2);
-      MDBX_txn *txn = mdbx_calloc(1, size);
-      if (txn) {
-        txn->mt_dbs = (MDBX_db *)((char *)txn + tsize);
-        txn->tw.cursors = (MDBX_cursor **)(txn->mt_dbs + env->me_maxdbs);
-        txn->mt_dbiseqs = (unsigned *)(txn->tw.cursors + env->me_maxdbs);
-        txn->mt_dbistate = (uint8_t *)(txn->mt_dbiseqs + env->me_maxdbs);
-        txn->mt_env = env;
-        txn->mt_dbxs = env->me_dbxs;
-        txn->mt_flags = MDBX_TXN_FINISHED;
-        env->me_txn0 = txn;
-        rc = mdbx_dpl_alloc(txn);
-        if (likely(rc == MDBX_SUCCESS)) {
-          txn->tw.retired_pages = mdbx_pnl_alloc(MDBX_PNL_INITIAL);
-          txn->tw.reclaimed_pglist = mdbx_pnl_alloc(MDBX_PNL_INITIAL);
-          if (unlikely(!txn->tw.retired_pages || !txn->tw.reclaimed_pglist))
-            rc = MDBX_ENOMEM;
-        }
-      } else
-        rc = MDBX_ENOMEM;
-    }
-  }
-
-#if MDBX_DEBUG
-  if (rc == MDBX_SUCCESS) {
-    MDBX_meta *meta = mdbx_meta_head(env);
-    MDBX_db *db = &meta->mm_dbs[MAIN_DBI];
-
-    mdbx_debug("opened database version %u, pagesize %u",
-               (uint8_t)unaligned_peek_u64(4, meta->mm_magic_and_version),
-               env->me_psize);
-    mdbx_debug("using meta page %" PRIaPGNO ", txn %" PRIaTXN,
-               data_page(meta)->mp_pgno, mdbx_meta_txnid_fluid(env, meta));
-    mdbx_debug("depth: %u", db->md_depth);
-    mdbx_debug("entries: %" PRIu64, db->md_entries);
-    mdbx_debug("branch pages: %" PRIaPGNO, db->md_branch_pages);
-    mdbx_debug("leaf pages: %" PRIaPGNO, db->md_leaf_pages);
-    mdbx_debug("overflow pages: %" PRIaPGNO, db->md_overflow_pages);
-    mdbx_debug("root: %" PRIaPGNO, db->md_root);
-    mdbx_debug("schema_altered: %" PRIaTXN, db->md_mod_txnid);
-  }
-#endif
-
-bailout:
-  if (rc != MDBX_SUCCESS) {
-    rc = mdbx_env_close0(env) ? MDBX_PANIC : rc;
-    env->me_flags =
-        saved_me_flags | ((rc != MDBX_PANIC) ? 0 : MDBX_FATAL_ERROR);
-  } else {
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-    mdbx_txn_valgrind(env, nullptr);
-#endif
-  }
-  mdbx_free(env_pathname.buffer_for_free);
-  return rc;
-}
-
-/* Destroy resources from mdbx_env_open(), clear our readers & DBIs */
-static __cold int mdbx_env_close0(MDBX_env *env) {
-  env->me_stuck_meta = -1;
-  if (!(env->me_flags & MDBX_ENV_ACTIVE)) {
-    mdbx_ensure(env, env->me_lcklist_next == nullptr);
-    return MDBX_SUCCESS;
-  }
-
-  env->me_flags &= ~MDBX_ENV_ACTIVE;
-  env->me_oldest = nullptr;
-  env->me_sync_timestamp = nullptr;
-  env->me_autosync_period = nullptr;
-  env->me_unsynced_pages = nullptr;
-  env->me_autosync_threshold = nullptr;
-  env->me_discarded_tail = nullptr;
-  env->me_meta_sync_txnid = nullptr;
-  if (env->me_flags & MDBX_ENV_TXKEY)
-    mdbx_rthc_remove(env->me_txkey);
-
-  lcklist_lock();
-  const int rc = lcklist_detach_locked(env);
-  lcklist_unlock();
-
-  if (env->me_map) {
-    mdbx_munmap(&env->me_dxb_mmap);
-#ifdef MDBX_USE_VALGRIND
-    VALGRIND_DISCARD(env->me_valgrind_handle);
-    env->me_valgrind_handle = -1;
-#endif
-  }
-
-  if (env->me_dsync_fd != INVALID_HANDLE_VALUE) {
-    (void)mdbx_closefile(env->me_dsync_fd);
-    env->me_dsync_fd = INVALID_HANDLE_VALUE;
-  }
-
-  if (env->me_lazy_fd != INVALID_HANDLE_VALUE) {
-    (void)mdbx_closefile(env->me_lazy_fd);
-    env->me_lazy_fd = INVALID_HANDLE_VALUE;
-  }
-
-  if (env->me_lck)
-    mdbx_munmap(&env->me_lck_mmap);
-
-  if (env->me_lfd != INVALID_HANDLE_VALUE) {
-    (void)mdbx_closefile(env->me_lfd);
-    env->me_lfd = INVALID_HANDLE_VALUE;
-  }
-
-  if (env->me_dbxs) {
-    for (unsigned i = env->me_numdbs; --i >= CORE_DBS;)
-      mdbx_free(env->me_dbxs[i].md_name.iov_base);
-    mdbx_free(env->me_dbxs);
-  }
-  mdbx_memalign_free(env->me_pbuf);
-  mdbx_free(env->me_dbiseqs);
-  mdbx_free(env->me_dbflags);
-  mdbx_free(env->me_pathname);
-  if (env->me_txn0) {
-    mdbx_dpl_free(env->me_txn0);
-    mdbx_txl_free(env->me_txn0->tw.lifo_reclaimed);
-    mdbx_pnl_free(env->me_txn0->tw.retired_pages);
-    mdbx_pnl_free(env->me_txn0->tw.spill_pages);
-    mdbx_pnl_free(env->me_txn0->tw.reclaimed_pglist);
-    mdbx_free(env->me_txn0);
-  }
-  env->me_flags = 0;
-  return rc;
-}
-
-__cold int mdbx_env_close_ex(MDBX_env *env, bool dont_sync) {
-  MDBX_page *dp;
-  int rc = MDBX_SUCCESS;
-
-  if (unlikely(!env))
-    return MDBX_EINVAL;
-
-  if (unlikely(env->me_signature.weak != MDBX_ME_SIGNATURE))
-    return MDBX_EBADSIGN;
-
-#if MDBX_ENV_CHECKPID || !(defined(_WIN32) || defined(_WIN64))
-  /* Check the PID even if MDBX_ENV_CHECKPID=0 on non-Windows
-   * platforms (i.e. where fork() is available).
-   * This is required to legitimize a call after fork()
-   * from a child process, that should be allowed to free resources. */
-  if (unlikely(env->me_pid != mdbx_getpid()))
-    env->me_flags |= MDBX_FATAL_ERROR;
-#endif /* MDBX_ENV_CHECKPID */
-
-  if ((env->me_flags & (MDBX_RDONLY | MDBX_FATAL_ERROR)) == 0 && env->me_txn0) {
-    if (env->me_txn0->mt_owner && env->me_txn0->mt_owner != mdbx_thread_self())
-      return MDBX_BUSY;
-  } else
-    dont_sync = true;
-
-  if (!atomic_cas32(&env->me_signature, MDBX_ME_SIGNATURE, 0))
-    return MDBX_EBADSIGN;
-
-  if (!dont_sync) {
-#if defined(_WIN32) || defined(_WIN64)
-    /* On windows, without blocking is impossible to determine whether another
-     * process is running a writing transaction or not.
-     * Because in the "owner died" condition kernel don't release
-     * file lock immediately. */
-    rc = mdbx_env_sync_internal(env, true, false);
-    rc = (rc == MDBX_RESULT_TRUE) ? MDBX_SUCCESS : rc;
-#else
-    struct stat st;
-    if (unlikely(fstat(env->me_lazy_fd, &st)))
-      rc = errno;
-    else if (st.st_nlink > 0 /* don't sync deleted files */) {
-      rc = mdbx_env_sync_internal(env, true, true);
-      rc = (rc == MDBX_BUSY || rc == EAGAIN || rc == EACCES || rc == EBUSY ||
-            rc == EWOULDBLOCK || rc == MDBX_RESULT_TRUE)
-               ? MDBX_SUCCESS
-               : rc;
-    }
-#endif
-  }
-
-  mdbx_assert(env, env->me_signature.weak == 0);
-  rc = mdbx_env_close0(env) ? MDBX_PANIC : rc;
-  mdbx_ensure(env, mdbx_fastmutex_destroy(&env->me_dbi_lock) == MDBX_SUCCESS);
-#if defined(_WIN32) || defined(_WIN64)
-  /* me_remap_guard don't have destructor (Slim Reader/Writer Lock) */
-  DeleteCriticalSection(&env->me_windowsbug_lock);
-#else
-  mdbx_ensure(env,
-              mdbx_fastmutex_destroy(&env->me_remap_guard) == MDBX_SUCCESS);
-#endif /* Windows */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV
-  mdbx_ensure(env, mdbx_ipclock_destroy(&env->me_lckless_stub.wlock) == 0);
-#endif /* MDBX_LOCKING */
-
-  while ((dp = env->me_dp_reserve) != NULL) {
-    ASAN_UNPOISON_MEMORY_REGION(dp, env->me_psize);
-    VALGRIND_MAKE_MEM_DEFINED(&dp->mp_next, sizeof(dp->mp_next));
-    env->me_dp_reserve = dp->mp_next;
-    mdbx_free(dp);
-  }
-  VALGRIND_DESTROY_MEMPOOL(env);
-  mdbx_ensure(env, env->me_lcklist_next == nullptr);
-  env->me_pid = 0;
-  mdbx_free(env);
-
-  return rc;
-}
-
-__cold int mdbx_env_close(MDBX_env *env) {
-  return __inline_mdbx_env_close(env);
-}
-
-/* Compare two items pointing at aligned unsigned int's. */
-static int __hot cmp_int_align4(const MDBX_val *a, const MDBX_val *b) {
-  mdbx_assert(NULL, a->iov_len == b->iov_len);
-  switch (a->iov_len) {
-  case 4:
-    return CMP2INT(unaligned_peek_u32(4, a->iov_base),
-                   unaligned_peek_u32(4, b->iov_base));
-  case 8:
-    return CMP2INT(unaligned_peek_u64(4, a->iov_base),
-                   unaligned_peek_u64(4, b->iov_base));
-  default:
-    mdbx_assert_fail(NULL, "invalid size for INTEGERKEY/INTEGERDUP", __func__,
-                     __LINE__);
-    return 0;
-  }
-}
-
-/* Compare two items pointing at 2-byte aligned unsigned int's. */
-static int __hot cmp_int_align2(const MDBX_val *a, const MDBX_val *b) {
-  mdbx_assert(NULL, a->iov_len == b->iov_len);
-  switch (a->iov_len) {
-  case 4:
-    return CMP2INT(unaligned_peek_u32(2, a->iov_base),
-                   unaligned_peek_u32(2, b->iov_base));
-  case 8:
-    return CMP2INT(unaligned_peek_u64(2, a->iov_base),
-                   unaligned_peek_u64(2, b->iov_base));
-  default:
-    mdbx_assert_fail(NULL, "invalid size for INTEGERKEY/INTEGERDUP", __func__,
-                     __LINE__);
-    return 0;
-  }
-}
-
-/* Compare two items pointing at unsigned values with unknown alignment.
- *
- * This is also set as MDBX_INTEGERDUP|MDBX_DUPFIXED's MDBX_dbx.md_dcmp. */
-static int __hot cmp_int_unaligned(const MDBX_val *a, const MDBX_val *b) {
-  mdbx_assert(NULL, a->iov_len == b->iov_len);
-  switch (a->iov_len) {
-  case 4:
-    return CMP2INT(unaligned_peek_u32(1, a->iov_base),
-                   unaligned_peek_u32(1, b->iov_base));
-  case 8:
-    return CMP2INT(unaligned_peek_u64(1, a->iov_base),
-                   unaligned_peek_u64(1, b->iov_base));
-  default:
-    mdbx_assert_fail(NULL, "invalid size for INTEGERKEY/INTEGERDUP", __func__,
-                     __LINE__);
-    return 0;
-  }
-}
-
-/* Compare two items lexically */
-static int __hot cmp_lexical(const MDBX_val *a, const MDBX_val *b) {
-  if (a->iov_len == b->iov_len)
-    return memcmp(a->iov_base, b->iov_base, a->iov_len);
-
-  const int diff_len = (a->iov_len < b->iov_len) ? -1 : 1;
-  const size_t shortest = (a->iov_len < b->iov_len) ? a->iov_len : b->iov_len;
-  int diff_data = memcmp(a->iov_base, b->iov_base, shortest);
-  return likely(diff_data) ? diff_data : diff_len;
-}
-
-/* Compare two items in reverse byte order */
-static int __hot cmp_reverse(const MDBX_val *a, const MDBX_val *b) {
-  const uint8_t *pa = (const uint8_t *)a->iov_base + a->iov_len;
-  const uint8_t *pb = (const uint8_t *)b->iov_base + b->iov_len;
-  const size_t shortest = (a->iov_len < b->iov_len) ? a->iov_len : b->iov_len;
-
-  const uint8_t *const end = pa - shortest;
-  while (pa != end) {
-    int diff = *--pa - *--pb;
-    if (likely(diff))
-      return diff;
-  }
-  return CMP2INT(a->iov_len, b->iov_len);
-}
-
-/* Fast non-lexically comparator */
-static int __hot cmp_lenfast(const MDBX_val *a, const MDBX_val *b) {
-  int diff = CMP2INT(a->iov_len, b->iov_len);
-  return likely(diff) ? diff : memcmp(a->iov_base, b->iov_base, a->iov_len);
-}
-
-static bool unsure_equal(MDBX_cmp_func cmp, const MDBX_val *a,
-                         const MDBX_val *b) {
-  return cmp == cmp_lenfast || cmp == cmp_lexical || cmp == cmp_reverse ||
-         cmp == cmp_int_unaligned || cmp_lenfast(a, b) == 0;
-}
-
-/* Search for key within a page, using binary search.
- * Returns the smallest entry larger or equal to the key.
- * If exactp is non-null, stores whether the found entry was an exact match
- * in *exactp (1 or 0).
- * Updates the cursor index with the index of the found entry.
- * If no entry larger or equal to the key is found, returns NULL. */
-static MDBX_node *__hot mdbx_node_search(MDBX_cursor *mc, const MDBX_val *key,
-                                         int *exactp) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  const int nkeys = page_numkeys(mp);
-  DKBUF;
-
-  mdbx_debug("searching %u keys in %s %spage %" PRIaPGNO, nkeys,
-             IS_LEAF(mp) ? "leaf" : "branch", IS_SUBP(mp) ? "sub-" : "",
-             mp->mp_pgno);
-
-  int low = IS_LEAF(mp) ? 0 : 1;
-  int high = nkeys - 1;
-  *exactp = 0;
-  if (unlikely(high < low)) {
-    mc->mc_ki[mc->mc_top] = 0;
-    return NULL;
-  }
-
-  int rc = 0, i = 0;
-  MDBX_cmp_func *cmp = mc->mc_dbx->md_cmp;
-  MDBX_val nodekey;
-  if (unlikely(IS_LEAF2(mp))) {
-    mdbx_cassert(mc, mp->mp_leaf2_ksize == mc->mc_db->md_xsize);
-    nodekey.iov_len = mp->mp_leaf2_ksize;
-    do {
-      i = (low + high) >> 1;
-      nodekey.iov_base = page_leaf2key(mp, i, nodekey.iov_len);
-      mdbx_cassert(mc, (char *)mp + mc->mc_txn->mt_env->me_psize >=
-                           (char *)nodekey.iov_base + nodekey.iov_len);
-      rc = cmp(key, &nodekey);
-      mdbx_debug("found leaf index %u [%s], rc = %i", i, DKEY(&nodekey), rc);
-      if (unlikely(rc == 0)) {
-        *exactp = 1;
-        break;
-      }
-      low = (rc < 0) ? low : i + 1;
-      high = (rc < 0) ? i - 1 : high;
-    } while (likely(low <= high));
-
-    /* Found entry is less than the key. */
-    /* Skip to get the smallest entry larger than key. */
-    i += rc > 0;
-
-    /* store the key index */
-    mc->mc_ki[mc->mc_top] = (indx_t)i;
-    return (i < nkeys)
-               ? /* fake for LEAF2 */ (MDBX_node *)(intptr_t)-1
-               : /* There is no entry larger or equal to the key. */ NULL;
-  }
-
-  if (cmp == cmp_int_align2 && IS_BRANCH(mp))
-    /* Branch pages have no data, so if using integer keys,
-     * alignment is guaranteed. Use faster mdbx_cmp_int_align4(). */
-    cmp = cmp_int_align4;
-
-  MDBX_node *node;
-  do {
-    i = (low + high) >> 1;
-
-    node = page_node(mp, i);
-    nodekey.iov_len = node_ks(node);
-    nodekey.iov_base = node_key(node);
-    mdbx_cassert(mc, (char *)mp + mc->mc_txn->mt_env->me_psize >=
-                         (char *)nodekey.iov_base + nodekey.iov_len);
-
-    rc = cmp(key, &nodekey);
-    if (IS_LEAF(mp))
-      mdbx_debug("found leaf index %u [%s], rc = %i", i, DKEY(&nodekey), rc);
-    else
-      mdbx_debug("found branch index %u [%s -> %" PRIaPGNO "], rc = %i", i,
-                 DKEY(&nodekey), node_pgno(node), rc);
-    if (unlikely(rc == 0)) {
-      *exactp = 1;
-      break;
-    }
-    low = (rc < 0) ? low : i + 1;
-    high = (rc < 0) ? i - 1 : high;
-  } while (likely(low <= high));
-
-  /* Found entry is less than the key. */
-  /* Skip to get the smallest entry larger than key. */
-  i += rc > 0;
-
-  /* store the key index */
-  mc->mc_ki[mc->mc_top] = (indx_t)i;
-  return (i < nkeys) ? page_node(mp, i)
-                     : /* There is no entry larger or equal to the key. */ NULL;
-}
-
-#if 0 /* unused for now */
-static void mdbx_cursor_adjust(MDBX_cursor *mc, func) {
-  MDBX_cursor *m2;
-
-  for (m2 = mc->mc_txn->tw.cursors[mc->mc_dbi]; m2; m2 = m2->mc_next) {
-    if (m2->mc_pg[m2->mc_top] == mc->mc_pg[mc->mc_top]) {
-      func(mc, m2);
-    }
-  }
-}
-#endif
-
-/* Pop a page off the top of the cursor's stack. */
-static __inline void mdbx_cursor_pop(MDBX_cursor *mc) {
-  if (mc->mc_snum) {
-    mdbx_debug("popped page %" PRIaPGNO " off db %d cursor %p",
-               mc->mc_pg[mc->mc_top]->mp_pgno, DDBI(mc), (void *)mc);
-    if (--mc->mc_snum) {
-      mc->mc_top--;
-    } else {
-      mc->mc_flags &= ~C_INITIALIZED;
-    }
-  }
-}
-
-/* Push a page onto the top of the cursor's stack.
- * Set MDBX_TXN_ERROR on failure. */
-static __inline int mdbx_cursor_push(MDBX_cursor *mc, MDBX_page *mp) {
-  mdbx_debug("pushing page %" PRIaPGNO " on db %d cursor %p", mp->mp_pgno,
-             DDBI(mc), (void *)mc);
-
-  if (unlikely(mc->mc_snum >= CURSOR_STACK)) {
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-    return MDBX_CURSOR_FULL;
-  }
-
-  mdbx_cassert(mc, mc->mc_snum < UINT16_MAX);
-  mc->mc_top = mc->mc_snum++;
-  mc->mc_pg[mc->mc_top] = mp;
-  mc->mc_ki[mc->mc_top] = 0;
-
-  return MDBX_SUCCESS;
-}
-
-/* Find the address of the page corresponding to a given page number.
- * Set MDBX_TXN_ERROR on failure.
- *
- * [in] mc    the cursor accessing the page.
- * [in] pgno  the page number for the page to retrieve.
- * [out] ret  address of a pointer where the page's address will be
- *            stored.
- * [out] lvl  dirtylist inheritance level of found page. 1=current txn,
- *            0=mapped page.
- *
- * Returns 0 on success, non-zero on failure. */
-__hot static int mdbx_page_get(MDBX_cursor *mc, pgno_t pgno, MDBX_page **ret,
-                               int *lvl, txnid_t pp_txnid) {
-  MDBX_txn *txn = mc->mc_txn;
-  if (unlikely(pgno >= txn->mt_next_pgno)) {
-    mdbx_error("page #%" PRIaPGNO " beyond next-pgno", pgno);
-  notfound:
-    *ret = nullptr;
-    txn->mt_flags |= MDBX_TXN_ERROR;
-    return MDBX_PAGE_NOTFOUND;
-  }
-
-  MDBX_env *const env = txn->mt_env;
-  MDBX_page *p = nullptr;
-  mdbx_assert(env, ((txn->mt_flags ^ env->me_flags) & MDBX_WRITEMAP) == 0);
-  mdbx_assert(env, pp_txnid >= MIN_TXNID && pp_txnid <= txn->mt_txnid);
-  const uint16_t illegal_bits =
-      (txn->mt_flags & MDBX_TXN_RDONLY)
-          ? ~(P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW)
-          : ~(P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW | P_DIRTY);
-  int level;
-  if (unlikely((txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_WRITEMAP)) == 0)) {
-    level = 1;
-    do {
-      /* Spilled pages were dirtied in this txn and flushed
-       * because the dirty list got full. Bring this page
-       * back in from the map (but don't unspill it here,
-       * leave that unless page_touch happens again). */
-      if (unlikely(txn->mt_flags & MDBX_TXN_SPILLS) && txn->tw.spill_pages &&
-          mdbx_pnl_exist(txn->tw.spill_pages, pgno << 1)) {
-        pp_txnid = txn->mt_txnid;
-        goto spilled;
-      }
-      p = mdbx_dpl_find(txn->tw.dirtylist, pgno);
-      if (p)
-        goto dirty;
-      level++;
-    } while ((txn = txn->mt_parent) != NULL);
-  }
-  level = 0;
-
-spilled:
-  p = pgno2page(env, pgno);
-
-dirty:
-  *(lvl ? lvl : &level) = level;
-  *ret = p;
-
-  if (unlikely(p->mp_pgno != pgno)) {
-    bad_page(
-        p, "mismatch actual pgno (%" PRIaPGNO ") != expected (%" PRIaPGNO ")\n",
-        p->mp_pgno, pgno);
-    goto notfound;
-  }
-
-  if (unlikely(p->mp_flags & illegal_bits)) {
-    bad_page(p, "invalid page's flags (%u)\n", p->mp_flags);
-    goto corrupted;
-  }
-
-  if (unlikely(p->mp_txnid >
-               ((p->mp_flags & P_DIRTY) ? UINT64_MAX : pp_txnid))) {
-    bad_page(p, "page mod-txnid (%" PRIaTXN ") > parent (%" PRIaTXN ")\n",
-             p->mp_txnid, pp_txnid);
-    goto corrupted;
-  }
-
-  if (unlikely((p->mp_upper < p->mp_lower ||
-                ((p->mp_lower | p->mp_upper) & 1) != 0 ||
-                PAGEHDRSZ + p->mp_upper > env->me_psize) &&
-               !IS_OVERFLOW(p))) {
-    bad_page(p, "invalid page lower(%u)/upper(%u) with limit (%u)\n",
-             p->mp_lower, p->mp_upper, page_space(env));
-    goto corrupted;
-  }
-
-  if (mdbx_audit_enabled())
-    return mdbx_page_check(mc, p, C_UPDATING);
-
-  return MDBX_SUCCESS;
-
-corrupted:
-  mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-  return MDBX_CORRUPTED;
-}
-
-/* Finish mdbx_page_search() / mdbx_page_search_lowest().
- * The cursor is at the root page, set up the rest of it. */
-__hot static int mdbx_page_search_root(MDBX_cursor *mc, const MDBX_val *key,
-                                       int flags) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  int rc;
-  DKBUF;
-
-  while (IS_BRANCH(mp)) {
-    MDBX_node *node;
-    int i;
-
-    mdbx_debug("branch page %" PRIaPGNO " has %u keys", mp->mp_pgno,
-               page_numkeys(mp));
-    /* Don't assert on branch pages in the GC. We can get here
-     * while in the process of rebalancing a GC branch page; we must
-     * let that proceed. ITS#8336 */
-    mdbx_cassert(mc, !mc->mc_dbi || page_numkeys(mp) > 1);
-    mdbx_debug("found index 0 to page %" PRIaPGNO, node_pgno(page_node(mp, 0)));
-
-    if (flags & (MDBX_PS_FIRST | MDBX_PS_LAST)) {
-      i = 0;
-      if (flags & MDBX_PS_LAST) {
-        i = page_numkeys(mp) - 1;
-        /* if already init'd, see if we're already in right place */
-        if (mc->mc_flags & C_INITIALIZED) {
-          if (mc->mc_ki[mc->mc_top] == i) {
-            mc->mc_top = mc->mc_snum++;
-            mp = mc->mc_pg[mc->mc_top];
-            goto ready;
-          }
-        }
-      }
-    } else {
-      int exact;
-      node = mdbx_node_search(mc, key, &exact);
-      if (node == NULL)
-        i = page_numkeys(mp) - 1;
-      else {
-        i = mc->mc_ki[mc->mc_top];
-        if (!exact) {
-          mdbx_cassert(mc, i > 0);
-          i--;
-        }
-      }
-      mdbx_debug("following index %u for key [%s]", i, DKEY(key));
-    }
-
-    mdbx_cassert(mc, i < (int)page_numkeys(mp));
-    node = page_node(mp, i);
-
-    if (unlikely((rc = mdbx_page_get(mc, node_pgno(node), &mp, NULL,
-                                     pp_txnid4chk(mp, mc->mc_txn))) != 0))
-      return rc;
-
-    mc->mc_ki[mc->mc_top] = (indx_t)i;
-    if (unlikely(rc = mdbx_cursor_push(mc, mp)))
-      return rc;
-
-  ready:
-    if (flags & MDBX_PS_MODIFY) {
-      if (unlikely((rc = mdbx_page_touch(mc)) != 0))
-        return rc;
-      mp = mc->mc_pg[mc->mc_top];
-    }
-  }
-
-  if (unlikely(!IS_LEAF(mp))) {
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-    return bad_page(mp, "index points to a page with 0x%02x flags\n",
-                    mp->mp_flags);
-  }
-
-  mdbx_debug("found leaf page %" PRIaPGNO " for key [%s]", mp->mp_pgno,
-             DKEY(key));
-  mc->mc_flags |= C_INITIALIZED;
-  mc->mc_flags &= ~C_EOF;
-
-  return MDBX_SUCCESS;
-}
-
-static int mdbx_setup_dbx(MDBX_dbx *const dbx, const MDBX_db *const db,
-                          const unsigned pagesize) {
-  if (unlikely(!dbx->md_cmp)) {
-    dbx->md_cmp = get_default_keycmp(db->md_flags);
-    dbx->md_dcmp = get_default_datacmp(db->md_flags);
-  }
-
-  dbx->md_klen_min =
-      (db->md_flags & MDBX_INTEGERKEY) ? 4 /* sizeof(uint32_t) */ : 0;
-  dbx->md_klen_max = mdbx_limits_keysize_max(pagesize, db->md_flags);
-  assert(dbx->md_klen_max != (unsigned)-1);
-
-  dbx->md_vlen_min = (db->md_flags & MDBX_INTEGERDUP)
-                         ? 4 /* sizeof(uint32_t) */
-                         : ((db->md_flags & MDBX_DUPFIXED) ? 1 : 0);
-  dbx->md_vlen_max = mdbx_limits_valsize_max(pagesize, db->md_flags);
-  assert(dbx->md_vlen_max != (unsigned)-1);
-
-  if ((db->md_flags & (MDBX_DUPFIXED | MDBX_INTEGERDUP)) != 0 && db->md_xsize) {
-    if (unlikely(db->md_xsize < dbx->md_vlen_min ||
-                 db->md_xsize > dbx->md_vlen_max)) {
-      mdbx_error("db.md_xsize (%u) <> min/max value-length (%zu/%zu)",
-                 db->md_xsize, dbx->md_vlen_min, dbx->md_vlen_max);
-      return MDBX_CORRUPTED;
-    }
-    dbx->md_vlen_min = dbx->md_vlen_max = db->md_xsize;
-  }
-  return MDBX_SUCCESS;
-}
-
-static int mdbx_fetch_sdb(MDBX_txn *txn, MDBX_dbi dbi) {
-  MDBX_cursor_couple couple;
-  if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
-    return MDBX_BAD_DBI;
-  int rc = mdbx_cursor_init(&couple.outer, txn, MAIN_DBI);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  MDBX_dbx *const dbx = &txn->mt_dbxs[dbi];
-  rc = mdbx_page_search(&couple.outer, &dbx->md_name, 0);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return (rc == MDBX_NOTFOUND) ? MDBX_BAD_DBI : rc;
-
-  MDBX_val data;
-  int exact = 0;
-  MDBX_node *node = mdbx_node_search(&couple.outer, &dbx->md_name, &exact);
-  if (unlikely(!exact))
-    return MDBX_BAD_DBI;
-  if (unlikely((node_flags(node) & (F_DUPDATA | F_SUBDATA)) != F_SUBDATA))
-    return MDBX_INCOMPATIBLE; /* not a named DB */
-
-  const txnid_t pp_txnid =
-      pp_txnid4chk(couple.outer.mc_pg[couple.outer.mc_top], txn);
-  rc = mdbx_node_read(&couple.outer, node, &data, pp_txnid);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(data.iov_len != sizeof(MDBX_db)))
-    return MDBX_INCOMPATIBLE; /* not a named DB */
-
-  uint16_t md_flags = UNALIGNED_PEEK_16(data.iov_base, MDBX_db, md_flags);
-  /* The txn may not know this DBI, or another process may
-   * have dropped and recreated the DB with other flags. */
-  MDBX_db *const db = &txn->mt_dbs[dbi];
-  if (unlikely((db->md_flags & DB_PERSISTENT_FLAGS) != md_flags))
-    return MDBX_INCOMPATIBLE;
-
-  memcpy(db, data.iov_base, sizeof(MDBX_db));
-  mdbx_tassert(txn, txn->mt_txnid >= pp_txnid);
-  if (unlikely(db->md_mod_txnid > pp_txnid)) {
-    mdbx_error("db.md_mod_txnid (%" PRIaTXN ") > page-txnid (%" PRIaTXN ")",
-               db->md_mod_txnid, pp_txnid);
-    return MDBX_CORRUPTED;
-  }
-  rc = mdbx_setup_dbx(dbx, db, txn->mt_env->me_psize);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  txn->mt_dbistate[dbi] &= ~DBI_STALE;
-  return MDBX_SUCCESS;
-}
-
-/* Search for the lowest key under the current branch page.
- * This just bypasses a numkeys check in the current page
- * before calling mdbx_page_search_root(), because the callers
- * are all in situations where the current page is known to
- * be underfilled. */
-__hot static int mdbx_page_search_lowest(MDBX_cursor *mc) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  mdbx_cassert(mc, IS_BRANCH(mp));
-  MDBX_node *node = page_node(mp, 0);
-  int rc;
-
-  if (unlikely((rc = mdbx_page_get(mc, node_pgno(node), &mp, NULL,
-                                   pp_txnid4chk(mp, mc->mc_txn))) != 0))
-    return rc;
-
-  mc->mc_ki[mc->mc_top] = 0;
-  if (unlikely(rc = mdbx_cursor_push(mc, mp)))
-    return rc;
-  return mdbx_page_search_root(mc, NULL, MDBX_PS_FIRST);
-}
-
-/* Search for the page a given key should be in.
- * Push it and its parent pages on the cursor stack.
- *
- * [in,out] mc  the cursor for this operation.
- * [in] key     the key to search for, or NULL for first/last page.
- * [in] flags   If MDBX_PS_MODIFY is set, visited pages in the DB
- *              are touched (updated with new page numbers).
- *              If MDBX_PS_FIRST or MDBX_PS_LAST is set, find first or last
- * leaf.
- *              This is used by mdbx_cursor_first() and mdbx_cursor_last().
- *              If MDBX_PS_ROOTONLY set, just fetch root node, no further
- *              lookups.
- *
- * Returns 0 on success, non-zero on failure. */
-__hot static int mdbx_page_search(MDBX_cursor *mc, const MDBX_val *key,
-                                  int flags) {
-  int rc;
-  pgno_t root;
-
-  /* Make sure the txn is still viable, then find the root from
-   * the txn's db table and set it as the root of the cursor's stack. */
-  if (unlikely(mc->mc_txn->mt_flags & MDBX_TXN_BLOCKED)) {
-    mdbx_debug("%s", "transaction has failed, must abort");
-    return MDBX_BAD_TXN;
-  }
-
-  /* Make sure we're using an up-to-date root */
-  if (unlikely(*mc->mc_dbistate & DBI_STALE)) {
-    rc = mdbx_fetch_sdb(mc->mc_txn, mc->mc_dbi);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-  root = mc->mc_db->md_root;
-
-  if (unlikely(root == P_INVALID)) { /* Tree is empty. */
-    mdbx_debug("%s", "tree is empty");
-    return MDBX_NOTFOUND;
-  }
-
-  mdbx_cassert(mc, root >= NUM_METAS);
-  if (!mc->mc_pg[0] || mc->mc_pg[0]->mp_pgno != root) {
-    if (unlikely((rc = mdbx_page_get(
-                      mc, root, &mc->mc_pg[0], NULL,
-                      (/* maybe zero in legacy DB */ mc->mc_db->md_mod_txnid &&
-                       !(*mc->mc_dbistate & DBI_DIRTY))
-                          ? mc->mc_db->md_mod_txnid
-                          : mc->mc_txn->mt_txnid)) != 0))
-      return rc;
-  }
-
-  mc->mc_snum = 1;
-  mc->mc_top = 0;
-
-  mdbx_debug("db %d root page %" PRIaPGNO " has flags 0x%X", DDBI(mc), root,
-             mc->mc_pg[0]->mp_flags);
-
-  if (flags & MDBX_PS_MODIFY) {
-    if (unlikely(rc = mdbx_page_touch(mc)))
-      return rc;
-  }
-
-  if (flags & MDBX_PS_ROOTONLY)
-    return MDBX_SUCCESS;
-
-  return mdbx_page_search_root(mc, key, flags);
-}
-
-/* Return the data associated with a given node.
- *
- * [in] mc      The cursor for this operation.
- * [in] leaf    The node being read.
- * [out] data   Updated to point to the node's data.
- *
- * Returns 0 on success, non-zero on failure. */
-static __always_inline int mdbx_node_read(MDBX_cursor *mc, MDBX_node *node,
-                                          MDBX_val *data,
-                                          const txnid_t pp_txnid) {
-  data->iov_len = node_ds(node);
-  data->iov_base = node_data(node);
-  if (unlikely(F_ISSET(node_flags(node), F_BIGDATA))) {
-    /* Read overflow data. */
-    MDBX_page *omp; /* overflow page */
-    int rc = mdbx_page_get(mc, node_largedata_pgno(node), &omp, NULL, pp_txnid);
-    if (unlikely((rc != MDBX_SUCCESS))) {
-      mdbx_debug("read overflow page %" PRIaPGNO " failed",
-                 node_largedata_pgno(node));
-      return rc;
-    }
-    data->iov_base = page_data(omp);
-  }
-  return MDBX_SUCCESS;
-}
-
-int mdbx_get(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key, MDBX_val *data) {
-  DKBUF;
-  mdbx_debug("===> get db %u key [%s]", dbi, DKEY(key));
-
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!key || !data))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  MDBX_cursor_couple cx;
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  int exact = 0;
-  return mdbx_cursor_set(&cx.outer, (MDBX_val *)key, data, MDBX_SET, &exact);
-}
-
-int mdbx_get_equal_or_great(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key,
-                            MDBX_val *data) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!key || !data))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
-    return MDBX_BAD_TXN;
-
-  MDBX_cursor_couple cx;
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  return mdbx_cursor_get(&cx.outer, key, data, MDBX_SET_LOWERBOUND);
-}
-
-int mdbx_get_ex(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
-                size_t *values_count) {
-  DKBUF;
-  mdbx_debug("===> get db %u key [%s]", dbi, DKEY(key));
-
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!key || !data))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  MDBX_cursor_couple cx;
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  int exact = 0;
-  rc = mdbx_cursor_set(&cx.outer, key, data, MDBX_SET_KEY, &exact);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (rc == MDBX_NOTFOUND && values_count)
-      *values_count = 0;
-    return rc;
-  }
-
-  if (values_count) {
-    *values_count = 1;
-    if (cx.outer.mc_xcursor != NULL) {
-      MDBX_node *node = page_node(cx.outer.mc_pg[cx.outer.mc_top],
-                                  cx.outer.mc_ki[cx.outer.mc_top]);
-      if (F_ISSET(node_flags(node), F_DUPDATA)) {
-        mdbx_tassert(txn, cx.outer.mc_xcursor == &cx.inner &&
-                              (cx.inner.mx_cursor.mc_flags & C_INITIALIZED));
-        *values_count =
-            (sizeof(*values_count) >= sizeof(cx.inner.mx_db.md_entries) ||
-             cx.inner.mx_db.md_entries <= PTRDIFF_MAX)
-                ? (size_t)cx.inner.mx_db.md_entries
-                : PTRDIFF_MAX;
-      }
-    }
-  }
-  return MDBX_SUCCESS;
-}
-
-/* Find a sibling for a page.
- * Replaces the page at the top of the cursor's stack with the specified
- * sibling, if one exists.
- *
- * [in] mc    The cursor for this operation.
- * [in] dir   SIBLING_LEFT or SIBLING_RIGHT.
- *
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_cursor_sibling(MDBX_cursor *mc, int dir) {
-  int rc;
-  MDBX_node *node;
-  MDBX_page *mp;
-  assert(dir == SIBLING_LEFT || dir == SIBLING_RIGHT);
-
-  if (unlikely(mc->mc_snum < 2))
-    return MDBX_NOTFOUND; /* root has no siblings */
-
-  mdbx_cursor_pop(mc);
-  mdbx_debug("parent page is page %" PRIaPGNO ", index %u",
-             mc->mc_pg[mc->mc_top]->mp_pgno, mc->mc_ki[mc->mc_top]);
-
-  if ((dir == SIBLING_RIGHT)
-          ? (mc->mc_ki[mc->mc_top] + 1u >= page_numkeys(mc->mc_pg[mc->mc_top]))
-          : (mc->mc_ki[mc->mc_top] == 0)) {
-    mdbx_debug("no more keys aside, moving to next %s sibling",
-               dir ? "right" : "left");
-    if (unlikely((rc = mdbx_cursor_sibling(mc, dir)) != MDBX_SUCCESS)) {
-      /* undo cursor_pop before returning */
-      mc->mc_top++;
-      mc->mc_snum++;
-      return rc;
-    }
-  } else {
-    assert((dir - 1) == -1 || (dir - 1) == 1);
-    mc->mc_ki[mc->mc_top] += (indx_t)(dir - 1);
-    mdbx_debug("just moving to %s index key %u",
-               (dir == SIBLING_RIGHT) ? "right" : "left",
-               mc->mc_ki[mc->mc_top]);
-  }
-  mdbx_cassert(mc, IS_BRANCH(mc->mc_pg[mc->mc_top]));
-
-  node = page_node(mp = mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-  if (unlikely((rc = mdbx_page_get(mc, node_pgno(node), &mp, NULL,
-                                   pp_txnid4chk(mp, mc->mc_txn))) != 0)) {
-    /* mc will be inconsistent if caller does mc_snum++ as above */
-    mc->mc_flags &= ~(C_INITIALIZED | C_EOF);
-    return rc;
-  }
-
-  rc = mdbx_cursor_push(mc, mp);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  mc->mc_ki[mc->mc_top] =
-      (indx_t)((dir == SIBLING_LEFT) ? page_numkeys(mp) - 1 : 0);
-  return MDBX_SUCCESS;
-}
-
-/* Move the cursor to the next data item. */
-static int mdbx_cursor_next(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
-                            MDBX_cursor_op op) {
-  MDBX_page *mp;
-  MDBX_node *node;
-  int rc;
-
-  if ((mc->mc_flags & C_DEL) && op == MDBX_NEXT_DUP)
-    return MDBX_NOTFOUND;
-
-  if (!(mc->mc_flags & C_INITIALIZED))
-    return mdbx_cursor_first(mc, key, data);
-
-  mp = mc->mc_pg[mc->mc_top];
-  if (mc->mc_flags & C_EOF) {
-    if (mc->mc_ki[mc->mc_top] + 1u >= page_numkeys(mp))
-      return MDBX_NOTFOUND;
-    mc->mc_flags ^= C_EOF;
-  }
-
-  if (mc->mc_db->md_flags & MDBX_DUPSORT) {
-    node = page_node(mp, mc->mc_ki[mc->mc_top]);
-    if (F_ISSET(node_flags(node), F_DUPDATA)) {
-      if (op == MDBX_NEXT || op == MDBX_NEXT_DUP) {
-        rc =
-            mdbx_cursor_next(&mc->mc_xcursor->mx_cursor, data, NULL, MDBX_NEXT);
-        if (op != MDBX_NEXT || rc != MDBX_NOTFOUND) {
-          if (likely(rc == MDBX_SUCCESS))
-            get_key_optional(node, key);
-          return rc;
-        }
-      }
-    } else {
-      mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
-      if (op == MDBX_NEXT_DUP)
-        return MDBX_NOTFOUND;
-    }
-  }
-
-  mdbx_debug("cursor_next: top page is %" PRIaPGNO " in cursor %p", mp->mp_pgno,
-             (void *)mc);
-  if (mc->mc_flags & C_DEL) {
-    mc->mc_flags ^= C_DEL;
-    goto skip;
-  }
-
-  int ki = mc->mc_ki[mc->mc_top];
-  mc->mc_ki[mc->mc_top] = (indx_t)++ki;
-  const int numkeys = page_numkeys(mp);
-  if (unlikely(ki >= numkeys)) {
-    mdbx_debug("%s", "=====> move to next sibling page");
-    mc->mc_ki[mc->mc_top] = (indx_t)(numkeys - 1);
-    if (unlikely((rc = mdbx_cursor_sibling(mc, SIBLING_RIGHT)) !=
-                 MDBX_SUCCESS)) {
-      mc->mc_flags |= C_EOF;
-      return rc;
-    }
-    mp = mc->mc_pg[mc->mc_top];
-    mdbx_debug("next page is %" PRIaPGNO ", key index %u", mp->mp_pgno,
-               mc->mc_ki[mc->mc_top]);
-  }
-
-skip:
-  mdbx_debug("==> cursor points to page %" PRIaPGNO
-             " with %u keys, key index %u",
-             mp->mp_pgno, page_numkeys(mp), mc->mc_ki[mc->mc_top]);
-
-  if (unlikely(!IS_LEAF(mp)))
-    return MDBX_CORRUPTED;
-
-  if (IS_LEAF2(mp)) {
-    if (likely(key)) {
-      key->iov_len = mc->mc_db->md_xsize;
-      key->iov_base = page_leaf2key(mp, mc->mc_ki[mc->mc_top], key->iov_len);
-    }
-    return MDBX_SUCCESS;
-  }
-
-  node = page_node(mp, mc->mc_ki[mc->mc_top]);
-  if (F_ISSET(node_flags(node), F_DUPDATA)) {
-    rc = mdbx_xcursor_init1(mc, node, mp);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  } else if (likely(data)) {
-    if (unlikely((rc = mdbx_node_read(mc, node, data,
-                                      pp_txnid4chk(mp, mc->mc_txn))) !=
-                 MDBX_SUCCESS))
-      return rc;
-  }
-
-  get_key_optional(node, key);
-  return MDBX_SUCCESS;
-}
-
-/* Move the cursor to the previous data item. */
-static int mdbx_cursor_prev(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
-                            MDBX_cursor_op op) {
-  MDBX_page *mp;
-  MDBX_node *node;
-  int rc;
-
-  if ((mc->mc_flags & C_DEL) && op == MDBX_PREV_DUP)
-    return MDBX_NOTFOUND;
-
-  if (!(mc->mc_flags & C_INITIALIZED)) {
-    rc = mdbx_cursor_last(mc, key, data);
-    if (unlikely(rc))
-      return rc;
-    mc->mc_ki[mc->mc_top]++;
-  }
-
-  mp = mc->mc_pg[mc->mc_top];
-  if ((mc->mc_db->md_flags & MDBX_DUPSORT) &&
-      mc->mc_ki[mc->mc_top] < page_numkeys(mp)) {
-    node = page_node(mp, mc->mc_ki[mc->mc_top]);
-    if (F_ISSET(node_flags(node), F_DUPDATA)) {
-      if (op == MDBX_PREV || op == MDBX_PREV_DUP) {
-        rc =
-            mdbx_cursor_prev(&mc->mc_xcursor->mx_cursor, data, NULL, MDBX_PREV);
-        if (op != MDBX_PREV || rc != MDBX_NOTFOUND) {
-          if (likely(rc == MDBX_SUCCESS)) {
-            get_key_optional(node, key);
-            mc->mc_flags &= ~C_EOF;
-          }
-          return rc;
-        }
-      }
-    } else {
-      mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
-      if (op == MDBX_PREV_DUP)
-        return MDBX_NOTFOUND;
-    }
-  }
-
-  mdbx_debug("cursor_prev: top page is %" PRIaPGNO " in cursor %p", mp->mp_pgno,
-             (void *)mc);
-
-  mc->mc_flags &= ~(C_EOF | C_DEL);
-
-  int ki = mc->mc_ki[mc->mc_top];
-  mc->mc_ki[mc->mc_top] = (indx_t)--ki;
-  if (unlikely(ki < 0)) {
-    mc->mc_ki[mc->mc_top] = 0;
-    mdbx_debug("%s", "=====> move to prev sibling page");
-    if ((rc = mdbx_cursor_sibling(mc, SIBLING_LEFT)) != MDBX_SUCCESS)
-      return rc;
-    mp = mc->mc_pg[mc->mc_top];
-    mdbx_debug("prev page is %" PRIaPGNO ", key index %u", mp->mp_pgno,
-               mc->mc_ki[mc->mc_top]);
-  }
-  mdbx_debug("==> cursor points to page %" PRIaPGNO
-             " with %u keys, key index %u",
-             mp->mp_pgno, page_numkeys(mp), mc->mc_ki[mc->mc_top]);
-
-  if (unlikely(!IS_LEAF(mp)))
-    return MDBX_CORRUPTED;
-
-  if (IS_LEAF2(mp)) {
-    if (likely(key)) {
-      key->iov_len = mc->mc_db->md_xsize;
-      key->iov_base = page_leaf2key(mp, mc->mc_ki[mc->mc_top], key->iov_len);
-    }
-    return MDBX_SUCCESS;
-  }
-
-  node = page_node(mp, mc->mc_ki[mc->mc_top]);
-
-  if (F_ISSET(node_flags(node), F_DUPDATA)) {
-    rc = mdbx_xcursor_init1(mc, node, mp);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    rc = mdbx_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  } else if (likely(data)) {
-    if (unlikely((rc = mdbx_node_read(mc, node, data,
-                                      pp_txnid4chk(mp, mc->mc_txn))) !=
-                 MDBX_SUCCESS))
-      return rc;
-  }
-
-  get_key_optional(node, key);
-  return MDBX_SUCCESS;
-}
-
-/* Set the cursor on a specific data item. */
-static int mdbx_cursor_set(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
-                           MDBX_cursor_op op, int *exactp) {
-  int rc;
-  MDBX_page *mp;
-  MDBX_node *node = NULL;
-  int stub_exactp;
-  DKBUF;
-
-  exactp = exactp ? exactp : &stub_exactp;
-
-  if (unlikely(key->iov_len < mc->mc_dbx->md_klen_min ||
-               key->iov_len > mc->mc_dbx->md_klen_max)) {
-    mdbx_cassert(mc, !"Invalid key-size");
-    return MDBX_BAD_VALSIZE;
-  }
-
-  MDBX_val aligned_key = *key;
-  uint64_t aligned_keybytes;
-  if (mc->mc_db->md_flags & MDBX_INTEGERKEY) {
-    switch (aligned_key.iov_len) {
-    default:
-      mdbx_cassert(mc, !"key-size is invalid for MDBX_INTEGERKEY");
-      return MDBX_BAD_VALSIZE;
-    case 4:
-      if (unlikely(3 & (uintptr_t)aligned_key.iov_base))
-        /* copy instead of return error to avoid break compatibility */
-        aligned_key.iov_base =
-            memcpy(&aligned_keybytes, aligned_key.iov_base, 4);
-      break;
-    case 8:
-      if (unlikely(7 & (uintptr_t)aligned_key.iov_base))
-        /* copy instead of return error to avoid break compatibility */
-        aligned_key.iov_base =
-            memcpy(&aligned_keybytes, aligned_key.iov_base, 8);
-      break;
-    }
-  }
-
-  if (mc->mc_xcursor)
-    mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
-
-  /* See if we're already on the right page */
-  if (mc->mc_flags & C_INITIALIZED) {
-    MDBX_val nodekey;
-
-    mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
-    mp = mc->mc_pg[mc->mc_top];
-    if (unlikely(!page_numkeys(mp))) {
-      mc->mc_ki[mc->mc_top] = 0;
-      mc->mc_flags |= C_EOF;
-      return MDBX_NOTFOUND;
-    }
-    if (IS_LEAF2(mp)) {
-      nodekey.iov_len = mc->mc_db->md_xsize;
-      nodekey.iov_base = page_leaf2key(mp, 0, nodekey.iov_len);
-    } else {
-      node = page_node(mp, 0);
-      get_key(node, &nodekey);
-    }
-    rc = mc->mc_dbx->md_cmp(&aligned_key, &nodekey);
-    if (unlikely(rc == 0)) {
-      /* Probably happens rarely, but first node on the page
-       * was the one we wanted. */
-      mc->mc_ki[mc->mc_top] = 0;
-      *exactp = 1;
-      mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
-                               page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                           (mc->mc_flags & C_EOF));
-      goto set1;
-    }
-    if (rc > 0) {
-      const unsigned nkeys = page_numkeys(mp);
-      unsigned i;
-      if (nkeys > 1) {
-        if (IS_LEAF2(mp)) {
-          nodekey.iov_base = page_leaf2key(mp, nkeys - 1, nodekey.iov_len);
-        } else {
-          node = page_node(mp, nkeys - 1);
-          get_key(node, &nodekey);
-        }
-        rc = mc->mc_dbx->md_cmp(&aligned_key, &nodekey);
-        if (rc == 0) {
-          /* last node was the one we wanted */
-          mdbx_cassert(mc, nkeys >= 1 && nkeys <= UINT16_MAX + 1);
-          mc->mc_ki[mc->mc_top] = (indx_t)(nkeys - 1);
-          *exactp = 1;
-          mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
-                                   page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                               (mc->mc_flags & C_EOF));
-          goto set1;
-        }
-        if (rc < 0) {
-          if (mc->mc_ki[mc->mc_top] < page_numkeys(mp)) {
-            /* This is definitely the right page, skip search_page */
-            if (IS_LEAF2(mp)) {
-              nodekey.iov_base =
-                  page_leaf2key(mp, mc->mc_ki[mc->mc_top], nodekey.iov_len);
-            } else {
-              node = page_node(mp, mc->mc_ki[mc->mc_top]);
-              get_key(node, &nodekey);
-            }
-            rc = mc->mc_dbx->md_cmp(&aligned_key, &nodekey);
-            if (rc == 0) {
-              /* current node was the one we wanted */
-              *exactp = 1;
-              mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
-                                       page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                                   (mc->mc_flags & C_EOF));
-              goto set1;
-            }
-          }
-          rc = 0;
-          mc->mc_flags &= ~C_EOF;
-          goto set2;
-        }
-      }
-      /* If any parents have right-sibs, search.
-       * Otherwise, there's nothing further. */
-      for (i = 0; i < mc->mc_top; i++)
-        if (mc->mc_ki[i] < page_numkeys(mc->mc_pg[i]) - 1)
-          break;
-      if (i == mc->mc_top) {
-        /* There are no other pages */
-        mdbx_cassert(mc, nkeys <= UINT16_MAX);
-        mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
-        mc->mc_flags |= C_EOF;
-        return MDBX_NOTFOUND;
-      }
-    }
-    if (!mc->mc_top) {
-      /* There are no other pages */
-      mc->mc_ki[mc->mc_top] = 0;
-      if (op == MDBX_SET_RANGE) {
-        rc = 0;
-        goto set1;
-      } else {
-        mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
-                                 page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                             (mc->mc_flags & C_EOF));
-        return MDBX_NOTFOUND;
-      }
-    }
-  } else {
-    mc->mc_pg[0] = 0;
-  }
-
-  rc = mdbx_page_search(mc, &aligned_key, 0);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  mp = mc->mc_pg[mc->mc_top];
-  mdbx_cassert(mc, IS_LEAF(mp));
-
-set2:
-  node = mdbx_node_search(mc, &aligned_key, exactp);
-  if (!*exactp && op != MDBX_SET_RANGE) {
-    /* MDBX_SET specified and not an exact match. */
-    if (unlikely(mc->mc_ki[mc->mc_top] >= page_numkeys(mc->mc_pg[mc->mc_top])))
-      mc->mc_flags |= C_EOF;
-    return MDBX_NOTFOUND;
-  }
-
-  if (node == NULL) {
-    mdbx_debug("%s", "===> inexact leaf not found, goto sibling");
-    if (unlikely((rc = mdbx_cursor_sibling(mc, SIBLING_RIGHT)) !=
-                 MDBX_SUCCESS)) {
-      mc->mc_flags |= C_EOF;
-      return rc; /* no entries matched */
-    }
-    mp = mc->mc_pg[mc->mc_top];
-    mdbx_cassert(mc, IS_LEAF(mp));
-    if (!IS_LEAF2(mp))
-      node = page_node(mp, 0);
-  }
-  mdbx_cassert(mc,
-               mc->mc_ki[mc->mc_top] < page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                   (mc->mc_flags & C_EOF));
-
-set1:
-  mc->mc_flags |= C_INITIALIZED;
-  mc->mc_flags &= ~C_EOF;
-
-  if (IS_LEAF2(mp)) {
-    if (op == MDBX_SET_RANGE || op == MDBX_SET_KEY) {
-      key->iov_len = mc->mc_db->md_xsize;
-      key->iov_base = page_leaf2key(mp, mc->mc_ki[mc->mc_top], key->iov_len);
-    }
-    return MDBX_SUCCESS;
-  }
-
-  if (F_ISSET(node_flags(node), F_DUPDATA)) {
-    rc = mdbx_xcursor_init1(mc, node, mp);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    if (op == MDBX_SET || op == MDBX_SET_KEY || op == MDBX_SET_RANGE) {
-      rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
-    } else {
-      rc = mdbx_cursor_set(&mc->mc_xcursor->mx_cursor, data, NULL,
-                           MDBX_SET_RANGE, NULL);
-    }
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  } else if (likely(data)) {
-    if (op == MDBX_GET_BOTH || op == MDBX_GET_BOTH_RANGE) {
-      if (unlikely(data->iov_len < mc->mc_dbx->md_vlen_min ||
-                   data->iov_len > mc->mc_dbx->md_vlen_max)) {
-        mdbx_cassert(mc, !"Invalid data-size");
-        return MDBX_BAD_VALSIZE;
-      }
-      MDBX_val aligned_data = *data;
-      uint64_t aligned_databytes;
-      if (mc->mc_db->md_flags & MDBX_INTEGERDUP) {
-        switch (aligned_data.iov_len) {
-        default:
-          mdbx_cassert(mc, !"data-size is invalid for MDBX_INTEGERDUP");
-          return MDBX_BAD_VALSIZE;
-        case 4:
-          if (unlikely(3 & (uintptr_t)aligned_data.iov_base))
-            /* copy instead of return error to avoid break compatibility */
-            aligned_data.iov_base =
-                memcpy(&aligned_databytes, aligned_data.iov_base, 4);
-          break;
-        case 8:
-          if (unlikely(7 & (uintptr_t)aligned_data.iov_base))
-            /* copy instead of return error to avoid break compatibility */
-            aligned_data.iov_base =
-                memcpy(&aligned_databytes, aligned_data.iov_base, 8);
-          break;
-        }
-      }
-      MDBX_val olddata;
-      if (unlikely((rc = mdbx_node_read(
-                        mc, node, &olddata,
-                        pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn))) !=
-                   MDBX_SUCCESS))
-        return rc;
-      rc = mc->mc_dbx->md_dcmp(&aligned_data, &olddata);
-      if (rc) {
-        mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
-                                 page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                             (mc->mc_flags & C_EOF));
-        if (op != MDBX_GET_BOTH_RANGE || rc > 0)
-          return MDBX_NOTFOUND;
-        *exactp = 0;
-        rc = 0;
-      }
-      *data = olddata;
-    } else if (unlikely((rc = mdbx_node_read(mc, node, data,
-                                             pp_txnid4chk(mc->mc_pg[mc->mc_top],
-                                                          mc->mc_txn))) !=
-                        MDBX_SUCCESS))
-      return rc;
-  }
-
-  /* The key already matches in all other cases */
-  if (op == MDBX_SET_RANGE || op == MDBX_SET_KEY)
-    get_key_optional(node, key);
-
-  mdbx_debug("==> cursor placed on key [%s], data [%s]", DKEY(key), DVAL(data));
-  return rc;
-}
-
-/* Move the cursor to the first item in the database. */
-static int mdbx_cursor_first(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data) {
-  int rc;
-
-  if (mc->mc_xcursor)
-    mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
-
-  if (!(mc->mc_flags & C_INITIALIZED) || mc->mc_top) {
-    rc = mdbx_page_search(mc, NULL, MDBX_PS_FIRST);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  if (unlikely(!IS_LEAF(mc->mc_pg[mc->mc_top])))
-    return MDBX_CORRUPTED;
-
-  mc->mc_flags |= C_INITIALIZED;
-  mc->mc_flags &= ~C_EOF;
-  mc->mc_ki[mc->mc_top] = 0;
-
-  if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
-    if (likely(key)) {
-      key->iov_len = mc->mc_db->md_xsize;
-      key->iov_base = page_leaf2key(mc->mc_pg[mc->mc_top], 0, key->iov_len);
-    }
-    return MDBX_SUCCESS;
-  }
-
-  MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], 0);
-  if (F_ISSET(node_flags(node), F_DUPDATA)) {
-    rc = mdbx_xcursor_init1(mc, node, mc->mc_pg[mc->mc_top]);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
-    if (unlikely(rc))
-      return rc;
-  } else if (likely(data)) {
-    if (unlikely((rc = mdbx_node_read(
-                      mc, node, data,
-                      pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn))) !=
-                 MDBX_SUCCESS))
-      return rc;
-  }
-
-  get_key_optional(node, key);
-  return MDBX_SUCCESS;
-}
-
-/* Move the cursor to the last item in the database. */
-static int mdbx_cursor_last(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data) {
-  int rc;
-
-  if (mc->mc_xcursor)
-    mc->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
-
-  if (!(mc->mc_flags & C_INITIALIZED) || mc->mc_top) {
-    rc = mdbx_page_search(mc, NULL, MDBX_PS_LAST);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  if (unlikely(!IS_LEAF(mc->mc_pg[mc->mc_top])))
-    return MDBX_CORRUPTED;
-
-  mc->mc_ki[mc->mc_top] = (indx_t)page_numkeys(mc->mc_pg[mc->mc_top]) - 1;
-  mc->mc_flags |= C_INITIALIZED | C_EOF;
-
-  if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
-    if (likely(key)) {
-      key->iov_len = mc->mc_db->md_xsize;
-      key->iov_base = page_leaf2key(mc->mc_pg[mc->mc_top],
-                                    mc->mc_ki[mc->mc_top], key->iov_len);
-    }
-    return MDBX_SUCCESS;
-  }
-
-  MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-  if (F_ISSET(node_flags(node), F_DUPDATA)) {
-    rc = mdbx_xcursor_init1(mc, node, mc->mc_pg[mc->mc_top]);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    rc = mdbx_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
-    if (unlikely(rc))
-      return rc;
-  } else if (likely(data)) {
-    if (unlikely((rc = mdbx_node_read(
-                      mc, node, data,
-                      pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn))) !=
-                 MDBX_SUCCESS))
-      return rc;
-  }
-
-  get_key_optional(node, key);
-  return MDBX_SUCCESS;
-}
-
-int mdbx_cursor_get(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
-                    MDBX_cursor_op op) {
-  if (unlikely(mc == NULL))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  int rc = check_txn(mc->mc_txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  int exact = 0;
-  int (*mfunc)(MDBX_cursor * mc, MDBX_val * key, MDBX_val * data);
-  switch (op) {
-  case MDBX_GET_CURRENT: {
-    if (unlikely(!(mc->mc_flags & C_INITIALIZED)))
-      return MDBX_ENODATA;
-    MDBX_page *mp = mc->mc_pg[mc->mc_top];
-    const unsigned nkeys = page_numkeys(mp);
-    if (mc->mc_ki[mc->mc_top] >= nkeys) {
-      mdbx_cassert(mc, nkeys <= UINT16_MAX);
-      mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
-      mc->mc_flags |= C_EOF;
-      return MDBX_NOTFOUND;
-    }
-    mdbx_cassert(mc, nkeys > 0);
-
-    rc = MDBX_SUCCESS;
-    if (IS_LEAF2(mp)) {
-      key->iov_len = mc->mc_db->md_xsize;
-      key->iov_base = page_leaf2key(mp, mc->mc_ki[mc->mc_top], key->iov_len);
-    } else {
-      MDBX_node *node = page_node(mp, mc->mc_ki[mc->mc_top]);
-      get_key_optional(node, key);
-      if (data) {
-        if (F_ISSET(node_flags(node), F_DUPDATA)) {
-          if (unlikely(!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED))) {
-            rc = mdbx_xcursor_init1(mc, node, mp);
-            if (unlikely(rc != MDBX_SUCCESS))
-              return rc;
-            rc = mdbx_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
-            if (unlikely(rc))
-              return rc;
-          } else {
-            rc = mdbx_cursor_get(&mc->mc_xcursor->mx_cursor, data, NULL,
-                                 MDBX_GET_CURRENT);
-            if (unlikely(rc))
-              return rc;
-          }
-        } else {
-          rc = mdbx_node_read(mc, node, data, pp_txnid4chk(mp, mc->mc_txn));
-          if (unlikely(rc))
-            return rc;
-        }
-      }
-    }
-    break;
-  }
-  case MDBX_GET_BOTH:
-  case MDBX_GET_BOTH_RANGE:
-    if (unlikely(data == NULL))
-      return MDBX_EINVAL;
-    if (unlikely(mc->mc_xcursor == NULL))
-      return MDBX_INCOMPATIBLE;
-    /* fall through */
-    __fallthrough;
-  case MDBX_SET:
-  case MDBX_SET_KEY:
-  case MDBX_SET_RANGE:
-    if (unlikely(key == NULL))
-      return MDBX_EINVAL;
-    rc = mdbx_cursor_set(mc, key, data, op, &exact);
-    if (mc->mc_flags & C_INITIALIZED) {
-      mdbx_cassert(mc, mc->mc_snum > 0 && mc->mc_top < mc->mc_snum);
-      mdbx_cassert(mc, mc->mc_ki[mc->mc_top] <
-                               page_numkeys(mc->mc_pg[mc->mc_top]) ||
-                           (mc->mc_flags & C_EOF));
-    }
-    break;
-  case MDBX_GET_MULTIPLE:
-    if (unlikely(data == NULL || !(mc->mc_flags & C_INITIALIZED)))
-      return MDBX_EINVAL;
-    if (unlikely(!(mc->mc_db->md_flags & MDBX_DUPFIXED)))
-      return MDBX_INCOMPATIBLE;
-    rc = MDBX_SUCCESS;
-    if ((mc->mc_xcursor->mx_cursor.mc_flags & (C_INITIALIZED | C_EOF)) !=
-        C_INITIALIZED)
-      break;
-    goto fetchm;
-  case MDBX_NEXT_MULTIPLE:
-    if (unlikely(data == NULL))
-      return MDBX_EINVAL;
-    if (unlikely(!(mc->mc_db->md_flags & MDBX_DUPFIXED)))
-      return MDBX_INCOMPATIBLE;
-    rc = mdbx_cursor_next(mc, key, data, MDBX_NEXT_DUP);
-    if (rc == MDBX_SUCCESS) {
-      if (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
-        MDBX_cursor *mx;
-      fetchm:
-        mx = &mc->mc_xcursor->mx_cursor;
-        data->iov_len =
-            page_numkeys(mx->mc_pg[mx->mc_top]) * mx->mc_db->md_xsize;
-        data->iov_base = page_data(mx->mc_pg[mx->mc_top]);
-        mx->mc_ki[mx->mc_top] = (indx_t)page_numkeys(mx->mc_pg[mx->mc_top]) - 1;
-      } else {
-        rc = MDBX_NOTFOUND;
-      }
-    }
-    break;
-  case MDBX_PREV_MULTIPLE:
-    if (data == NULL)
-      return MDBX_EINVAL;
-    if (!(mc->mc_db->md_flags & MDBX_DUPFIXED))
-      return MDBX_INCOMPATIBLE;
-    rc = MDBX_SUCCESS;
-    if (!(mc->mc_flags & C_INITIALIZED))
-      rc = mdbx_cursor_last(mc, key, data);
-    if (rc == MDBX_SUCCESS) {
-      MDBX_cursor *mx = &mc->mc_xcursor->mx_cursor;
-      if (mx->mc_flags & C_INITIALIZED) {
-        rc = mdbx_cursor_sibling(mx, SIBLING_LEFT);
-        if (rc == MDBX_SUCCESS)
-          goto fetchm;
-      } else {
-        rc = MDBX_NOTFOUND;
-      }
-    }
-    break;
-  case MDBX_NEXT:
-  case MDBX_NEXT_DUP:
-  case MDBX_NEXT_NODUP:
-    rc = mdbx_cursor_next(mc, key, data, op);
-    break;
-  case MDBX_PREV:
-  case MDBX_PREV_DUP:
-  case MDBX_PREV_NODUP:
-    rc = mdbx_cursor_prev(mc, key, data, op);
-    break;
-  case MDBX_FIRST:
-    rc = mdbx_cursor_first(mc, key, data);
-    break;
-  case MDBX_FIRST_DUP:
-    mfunc = mdbx_cursor_first;
-  mmove:
-    if (unlikely(data == NULL || !(mc->mc_flags & C_INITIALIZED)))
-      return MDBX_EINVAL;
-    if (unlikely(mc->mc_xcursor == NULL))
-      return MDBX_INCOMPATIBLE;
-    if (mc->mc_ki[mc->mc_top] >= page_numkeys(mc->mc_pg[mc->mc_top])) {
-      mc->mc_ki[mc->mc_top] = (indx_t)page_numkeys(mc->mc_pg[mc->mc_top]);
-      mc->mc_flags |= C_EOF;
-      return MDBX_NOTFOUND;
-    }
-    {
-      MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-      if (!F_ISSET(node_flags(node), F_DUPDATA)) {
-        get_key_optional(node, key);
-        rc = mdbx_node_read(mc, node, data,
-                            pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn));
-        break;
-      }
-    }
-    if (unlikely(!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)))
-      return MDBX_EINVAL;
-    rc = mfunc(&mc->mc_xcursor->mx_cursor, data, NULL);
-    break;
-  case MDBX_LAST:
-    rc = mdbx_cursor_last(mc, key, data);
-    break;
-  case MDBX_LAST_DUP:
-    mfunc = mdbx_cursor_last;
-    goto mmove;
-  case MDBX_SET_LOWERBOUND: {
-    if (unlikely(key == NULL || data == NULL))
-      return MDBX_EINVAL;
-    MDBX_val save_data = *data;
-    rc = mdbx_cursor_set(mc, key, data, MDBX_SET_RANGE, &exact);
-    if (rc == MDBX_SUCCESS && exact && mc->mc_xcursor) {
-      mc->mc_flags &= ~C_DEL;
-      if (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
-        *data = save_data;
-        exact = 0;
-        rc = mdbx_cursor_set(&mc->mc_xcursor->mx_cursor, data, NULL,
-                             MDBX_SET_RANGE, &exact);
-        if (rc == MDBX_NOTFOUND) {
-          mdbx_cassert(mc, !exact);
-          rc = mdbx_cursor_next(mc, key, data, MDBX_NEXT_NODUP);
-        }
-      } else {
-        int cmp = mc->mc_dbx->md_dcmp(&save_data, data);
-        exact = (cmp == 0);
-        if (cmp > 0)
-          rc = mdbx_cursor_next(mc, key, data, MDBX_NEXT_NODUP);
-      }
-    }
-    if (rc == MDBX_SUCCESS && !exact)
-      rc = MDBX_RESULT_TRUE;
-    break;
-  }
-  default:
-    mdbx_debug("unhandled/unimplemented cursor operation %u", op);
-    return MDBX_EINVAL;
-  }
-
-  mc->mc_flags &= ~C_DEL;
-  return rc;
-}
-
-/* Touch all the pages in the cursor stack. Set mc_top.
- * Makes sure all the pages are writable, before attempting a write operation.
- * [in] mc The cursor to operate on. */
-static int mdbx_cursor_touch(MDBX_cursor *mc) {
-  int rc = MDBX_SUCCESS;
-
-  if (mc->mc_dbi >= CORE_DBS &&
-      (*mc->mc_dbistate & (DBI_DIRTY | DBI_DUPDATA)) == 0) {
-    mdbx_cassert(mc, (mc->mc_flags & C_RECLAIMING) == 0);
-    /* Touch DB record of named DB */
-    MDBX_cursor_couple cx;
-    if (TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi))
-      return MDBX_BAD_DBI;
-    rc = mdbx_cursor_init(&cx.outer, mc->mc_txn, MAIN_DBI);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    *mc->mc_dbistate |= DBI_DIRTY;
-    mc->mc_txn->mt_flags |= MDBX_TXN_DIRTY;
-    rc = mdbx_page_search(&cx.outer, &mc->mc_dbx->md_name, MDBX_PS_MODIFY);
-    if (unlikely(rc))
-      return rc;
-  }
-  mc->mc_top = 0;
-  if (mc->mc_snum) {
-    do {
-      rc = mdbx_page_touch(mc);
-    } while (!rc && ++(mc->mc_top) < mc->mc_snum);
-    mc->mc_top = mc->mc_snum - 1;
-  }
-  return rc;
-}
-
-int mdbx_cursor_put(MDBX_cursor *mc, const MDBX_val *key, MDBX_val *data,
-                    unsigned flags) {
-  MDBX_env *env;
-  MDBX_page *sub_root = NULL;
-  MDBX_val xdata, *rdata, dkey, olddata;
-  MDBX_db nested_dupdb;
-  int rc2;
-  DKBUF;
-
-  if (unlikely(mc == NULL || key == NULL || data == NULL))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  int rc = check_txn_rw(mc->mc_txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi)))
-    return MDBX_BAD_DBI;
-
-  mdbx_cassert(mc, cursor_is_tracked(mc));
-  env = mc->mc_txn->mt_env;
-
-  /* Check this first so counter will always be zero on any early failures. */
-  size_t mcount = 0, dcount = 0;
-  if (unlikely(flags & MDBX_MULTIPLE)) {
-    if (unlikely(flags & MDBX_RESERVE))
-      return MDBX_EINVAL;
-    if (unlikely(!F_ISSET(mc->mc_db->md_flags, MDBX_DUPFIXED)))
-      return MDBX_INCOMPATIBLE;
-    dcount = data[1].iov_len;
-    if (unlikely(dcount < 2 || data->iov_len == 0))
-      return MDBX_BAD_VALSIZE;
-    if (unlikely(mc->mc_db->md_xsize != data->iov_len) && mc->mc_db->md_xsize)
-      return MDBX_BAD_VALSIZE;
-    if (unlikely(dcount >
-                 MAX_MAPSIZE / 2 / (BRANCH_NODEMAX(MAX_PAGESIZE) - NODESIZE))) {
-      /* checking for multiplication overflow */
-      if (unlikely(dcount > MAX_MAPSIZE / 2 / data->iov_len))
-        return MDBX_TOO_LARGE;
-    }
-    data[1].iov_len = 0 /* reset done item counter */;
-  }
-
-  if (flags & MDBX_RESERVE) {
-    if (unlikely(mc->mc_db->md_flags & (MDBX_DUPSORT | MDBX_REVERSEDUP |
-                                        MDBX_INTEGERDUP | MDBX_DUPFIXED)))
-      return MDBX_INCOMPATIBLE;
-    data->iov_base = nullptr;
-  }
-
-  const unsigned nospill = flags & MDBX_NOSPILL;
-  flags -= nospill;
-
-  if (unlikely(mc->mc_txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
-    return (mc->mc_txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS
-                                                    : MDBX_BAD_TXN;
-
-  uint64_t aligned_keybytes, aligned_databytes;
-  MDBX_val aligned_key, aligned_data;
-  if (likely((mc->mc_flags & C_SUB) == 0)) {
-    if (unlikely(key->iov_len < mc->mc_dbx->md_klen_min ||
-                 key->iov_len > mc->mc_dbx->md_klen_max)) {
-      mdbx_cassert(mc, !"Invalid key-size");
-      return MDBX_BAD_VALSIZE;
-    }
-    if (unlikely(data->iov_len < mc->mc_dbx->md_vlen_min ||
-                 data->iov_len > mc->mc_dbx->md_vlen_max)) {
-      mdbx_cassert(mc, !"Invalid data-size");
-      return MDBX_BAD_VALSIZE;
-    }
-
-    if (mc->mc_db->md_flags & MDBX_INTEGERKEY) {
-      switch (key->iov_len) {
-      default:
-        mdbx_cassert(mc, !"key-size is invalid for MDBX_INTEGERKEY");
-        return MDBX_BAD_VALSIZE;
-      case 4:
-        if (unlikely(3 & (uintptr_t)key->iov_base)) {
-          /* copy instead of return error to avoid break compatibility */
-          aligned_key.iov_base =
-              memcpy(&aligned_keybytes, key->iov_base, aligned_key.iov_len = 4);
-          key = &aligned_key;
-        }
-        break;
-      case 8:
-        if (unlikely(7 & (uintptr_t)key->iov_base)) {
-          /* copy instead of return error to avoid break compatibility */
-          aligned_key.iov_base =
-              memcpy(&aligned_keybytes, key->iov_base, aligned_key.iov_len = 8);
-          key = &aligned_key;
-        }
-        break;
-      }
-    }
-    if (mc->mc_db->md_flags & MDBX_INTEGERDUP) {
-      switch (data->iov_len) {
-      default:
-        mdbx_cassert(mc, !"data-size is invalid for MDBX_INTEGERKEY");
-        return MDBX_BAD_VALSIZE;
-      case 4:
-        if (unlikely(3 & (uintptr_t)data->iov_base)) {
-          if (unlikely(flags & MDBX_MULTIPLE))
-            return MDBX_BAD_VALSIZE;
-          /* copy instead of return error to avoid break compatibility */
-          aligned_data.iov_base = memcpy(&aligned_databytes, data->iov_base,
-                                         aligned_data.iov_len = 4);
-          data = &aligned_data;
-        }
-        break;
-      case 8:
-        if (unlikely(7 & (uintptr_t)data->iov_base)) {
-          if (unlikely(flags & MDBX_MULTIPLE))
-            return MDBX_BAD_VALSIZE;
-          /* copy instead of return error to avoid break compatibility */
-          aligned_data.iov_base = memcpy(&aligned_databytes, data->iov_base,
-                                         aligned_data.iov_len = 8);
-          data = &aligned_data;
-        }
-        break;
-      }
-    }
-  }
-
-  mdbx_debug("==> put db %d key [%s], size %" PRIuPTR
-             ", data [%s] size %" PRIuPTR,
-             DDBI(mc), DKEY(key), key->iov_len,
-             DVAL((flags & MDBX_RESERVE) ? nullptr : data), data->iov_len);
-
-  int dupdata_flag = 0;
-  if ((flags & MDBX_CURRENT) != 0 && (mc->mc_flags & C_SUB) == 0) {
-    if (unlikely(flags & (MDBX_APPEND | MDBX_NOOVERWRITE)))
-      return MDBX_EINVAL;
-    /* Опция MDBX_CURRENT означает, что запрошено обновление текущей записи,
-     * на которой сейчас стоит курсор. Проверяем что переданный ключ совпадает
-     * со значением в текущей позиции курсора.
-     * Здесь проще вызвать mdbx_cursor_get(), так как для обслуживания таблиц
-     * с MDBX_DUPSORT также требуется текущий размер данных. */
-    MDBX_val current_key, current_data;
-    rc = mdbx_cursor_get(mc, &current_key, &current_data, MDBX_GET_CURRENT);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    if (mc->mc_dbx->md_cmp(key, &current_key) != 0)
-      return MDBX_EKEYMISMATCH;
-
-    if (unlikely((flags & MDBX_MULTIPLE)))
-      goto drop_current;
-
-    if (F_ISSET(mc->mc_db->md_flags, MDBX_DUPSORT)) {
-      MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-      if (F_ISSET(node_flags(node), F_DUPDATA)) {
-        mdbx_cassert(mc,
-                     mc->mc_xcursor != NULL &&
-                         (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED));
-        /* Если за ключом более одного значения, либо если размер данных
-         * отличается, то вместо обновления требуется удаление и
-         * последующая вставка. */
-        if (mc->mc_xcursor->mx_db.md_entries > 1 ||
-            current_data.iov_len != data->iov_len) {
-        drop_current:
-          rc = mdbx_cursor_del(mc, flags & MDBX_ALLDUPS);
-          if (unlikely(rc != MDBX_SUCCESS))
-            return rc;
-          flags -= MDBX_CURRENT;
-          goto skip_check_samedata;
-        }
-      } else if (unlikely(node_size(key, data) >
-                          /* See note inside leaf_size() */
-                          env->me_branch_nodemax)) {
-        rc = mdbx_cursor_del(mc, 0);
-        if (unlikely(rc != MDBX_SUCCESS))
-          return rc;
-        flags -= MDBX_CURRENT;
-        goto skip_check_samedata;
-      }
-    }
-    if (!(flags & MDBX_RESERVE) &&
-        unlikely(cmp_lenfast(&current_data, data) == 0))
-      return MDBX_SUCCESS /* the same data, nothing to update */;
-  skip_check_samedata:;
-  }
-
-  if (mc->mc_db->md_root == P_INVALID) {
-    /* new database, cursor has nothing to point to */
-    mc->mc_snum = 0;
-    mc->mc_top = 0;
-    mc->mc_flags &= ~C_INITIALIZED;
-    rc = MDBX_NO_ROOT;
-  } else if ((flags & MDBX_CURRENT) == 0) {
-    int exact = false;
-    if ((flags & MDBX_APPEND) && mc->mc_db->md_entries > 0) {
-      rc = mdbx_cursor_last(mc, &dkey, &olddata);
-      if (likely(rc == MDBX_SUCCESS)) {
-        rc = mc->mc_dbx->md_cmp(key, &dkey);
-        if (likely(rc > 0)) {
-          mc->mc_ki[mc->mc_top]++; /* step forward for appending */
-          rc = MDBX_NOTFOUND;
-        } else {
-          if (unlikely(rc != MDBX_SUCCESS || !(flags & MDBX_APPENDDUP)))
-            /* new-key < last-key
-             * or new-key == last-key without MDBX_APPENDDUP */
-            return MDBX_EKEYMISMATCH;
-          exact = true;
-        }
-      }
-    } else {
-      rc = mdbx_cursor_set(mc, (MDBX_val *)key, &olddata, MDBX_SET, &exact);
-    }
-    if (likely(rc == MDBX_SUCCESS)) {
-      if (exact) {
-        if (unlikely(flags & MDBX_NOOVERWRITE)) {
-          mdbx_debug("duplicate key [%s]", DKEY(key));
-          *data = olddata;
-          return MDBX_KEYEXIST;
-        }
-        if (unlikely(mc->mc_flags & C_SUB)) {
-          /* nested subtree of DUPSORT-database with the same key,
-           * nothing to update */
-          mdbx_assert(env, data->iov_len == 0 && olddata.iov_len == 0);
-          return MDBX_SUCCESS;
-        }
-        if (unlikely(flags & MDBX_ALLDUPS) && mc->mc_xcursor &&
-            (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)) {
-          rc = mdbx_cursor_del(mc, MDBX_ALLDUPS);
-          if (unlikely(rc != MDBX_SUCCESS))
-            return rc;
-          flags -= MDBX_ALLDUPS;
-          rc = MDBX_NOTFOUND;
-          exact = false;
-        } else /* checking for early exit without dirtying pages */
-            if (!(flags & (MDBX_RESERVE | MDBX_MULTIPLE)) &&
-                unlikely(mc->mc_dbx->md_dcmp(data, &olddata) == 0)) {
-          if (!mc->mc_xcursor)
-            /* the same data, nothing to update */
-            return MDBX_SUCCESS;
-          if (flags & MDBX_NODUPDATA)
-            return MDBX_KEYEXIST;
-          if (flags & MDBX_APPENDDUP)
-            return MDBX_EKEYMISMATCH;
-          if (likely(unsure_equal(mc->mc_dbx->md_dcmp, data, &olddata)))
-            /* data is match exactly byte-to-byte, nothing to update */
-            return MDBX_SUCCESS;
-          else {
-            /* The data has differences, but the user-provided comparator
-             * considers them equal. So continue update since called without.
-             * Continue to update since was called without MDBX_NODUPDATA. */
-          }
-        }
-      }
-    } else if (unlikely(rc != MDBX_NOTFOUND))
-      return rc;
-  }
-
-  mc->mc_flags &= ~C_DEL;
-
-  /* Cursor is positioned, check for room in the dirty list */
-  if (!nospill) {
-    if (unlikely(flags & MDBX_MULTIPLE)) {
-      rdata = &xdata;
-      xdata.iov_len = data->iov_len * dcount;
-    } else {
-      rdata = data;
-    }
-    if (unlikely(rc2 = mdbx_cursor_spill(mc, key, rdata)))
-      return rc2;
-  }
-
-  if (unlikely(rc == MDBX_NO_ROOT)) {
-    MDBX_page *np;
-    /* new database, write a root leaf page */
-    mdbx_debug("%s", "allocating new root leaf page");
-    if (unlikely(rc2 = mdbx_page_new(mc, P_LEAF, 1, &np))) {
-      return rc2;
-    }
-    rc2 = mdbx_cursor_push(mc, np);
-    if (unlikely(rc2 != MDBX_SUCCESS))
-      return rc2;
-    mc->mc_db->md_root = np->mp_pgno;
-    mc->mc_db->md_depth++;
-    if (mc->mc_db->md_flags & MDBX_INTEGERKEY) {
-      assert(key->iov_len >= mc->mc_dbx->md_klen_min &&
-             key->iov_len <= mc->mc_dbx->md_klen_max);
-      mc->mc_dbx->md_klen_min = mc->mc_dbx->md_klen_max = key->iov_len;
-    }
-    if (mc->mc_db->md_flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED)) {
-      assert(data->iov_len >= mc->mc_dbx->md_vlen_min &&
-             data->iov_len <= mc->mc_dbx->md_vlen_max);
-      assert(mc->mc_xcursor != NULL);
-      mc->mc_db->md_xsize = mc->mc_xcursor->mx_db.md_xsize =
-          (unsigned)(mc->mc_dbx->md_vlen_min = mc->mc_dbx->md_vlen_max =
-                         mc->mc_xcursor->mx_dbx.md_klen_min =
-                             mc->mc_xcursor->mx_dbx.md_klen_max =
-                                 data->iov_len);
-    }
-    if ((mc->mc_db->md_flags & (MDBX_DUPSORT | MDBX_DUPFIXED)) == MDBX_DUPFIXED)
-      np->mp_flags |= P_LEAF2;
-    mc->mc_flags |= C_INITIALIZED;
-  } else {
-    /* make sure all cursor pages are writable */
-    rc2 = mdbx_cursor_touch(mc);
-    if (unlikely(rc2))
-      return rc2;
-  }
-
-  bool insert_key, insert_data, do_sub = false;
-  insert_key = insert_data = (rc != MDBX_SUCCESS);
-  uint16_t fp_flags = P_LEAF | P_DIRTY;
-  MDBX_page *fp = env->me_pbuf;
-  fp->mp_txnid = pp_txnid2chk(mc->mc_txn);
-  if (insert_key) {
-    /* The key does not exist */
-    mdbx_debug("inserting key at index %i", mc->mc_ki[mc->mc_top]);
-    if ((mc->mc_db->md_flags & MDBX_DUPSORT) &&
-        node_size(key, data) >
-            /* See note inside leaf_size() */ env->me_branch_nodemax) {
-      /* Too big for a node, insert in sub-DB.  Set up an empty
-       * "old sub-page" for prep_subDB to expand to a full page. */
-      fp->mp_leaf2_ksize =
-          (mc->mc_db->md_flags & MDBX_DUPFIXED) ? (uint16_t)data->iov_len : 0;
-      fp->mp_lower = fp->mp_upper = 0;
-      olddata.iov_len = PAGEHDRSZ;
-      goto prep_subDB;
-    }
-  } else {
-    /* there's only a key anyway, so this is a no-op */
-    if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
-      char *ptr;
-      unsigned ksize = mc->mc_db->md_xsize;
-      if (unlikely(key->iov_len != ksize))
-        return MDBX_BAD_VALSIZE;
-      ptr = page_leaf2key(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], ksize);
-      memcpy(ptr, key->iov_base, ksize);
-    fix_parent:
-      /* if overwriting slot 0 of leaf, need to
-       * update branch key if there is a parent page */
-      if (mc->mc_top && !mc->mc_ki[mc->mc_top]) {
-        unsigned dtop = 1;
-        mc->mc_top--;
-        /* slot 0 is always an empty key, find real slot */
-        while (mc->mc_top && !mc->mc_ki[mc->mc_top]) {
-          mc->mc_top--;
-          dtop++;
-        }
-        if (mc->mc_ki[mc->mc_top])
-          rc2 = mdbx_update_key(mc, key);
-        else
-          rc2 = MDBX_SUCCESS;
-        mdbx_cassert(mc, mc->mc_top + dtop < UINT16_MAX);
-        mc->mc_top += (uint16_t)dtop;
-        if (rc2)
-          return rc2;
-      }
-
-      if (mdbx_audit_enabled()) {
-        int err = mdbx_cursor_check(mc, 0);
-        if (unlikely(err != MDBX_SUCCESS))
-          return err;
-      }
-      return MDBX_SUCCESS;
-    }
-
-  more:;
-    if (mdbx_audit_enabled()) {
-      int err = mdbx_cursor_check(mc, 0);
-      if (unlikely(err != MDBX_SUCCESS))
-        return err;
-    }
-    MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-
-    /* overflow page overwrites need special handling */
-    if (unlikely(F_ISSET(node_flags(node), F_BIGDATA))) {
-      int level, ovpages,
-          dpages = (node_size(key, data) >
-                    /* See note inside leaf_size() */ env->me_branch_nodemax)
-                       ? number_of_ovpages(env, data->iov_len)
-                       : 0;
-
-      const pgno_t pg = node_largedata_pgno(node);
-      MDBX_page *omp;
-      if (unlikely((rc2 = mdbx_page_get(
-                        mc, pg, &omp, &level,
-                        pp_txnid4chk(mc->mc_pg[mc->mc_top], mc->mc_txn))) != 0))
-        return rc2;
-      ovpages = omp->mp_pages;
-
-      /* Is the ov page large enough? */
-      if (unlikely(mc->mc_flags & C_GCFREEZE)
-              ? ovpages >= dpages
-              : ovpages ==
-                    /* LY: add configurable threshold to keep reserve space */
-                    dpages) {
-        if (!IS_DIRTY(omp) && (level || (env->me_flags & MDBX_WRITEMAP))) {
-          rc2 = mdbx_page_unspill(mc->mc_txn, omp, &omp);
-          if (unlikely(rc2))
-            return rc2;
-          level = 0; /* dirty in this txn or clean */
-        }
-        /* Is it dirty? */
-        if (IS_DIRTY(omp)) {
-          mdbx_cassert(mc, omp->mp_txnid > SAFE64_INVALID_THRESHOLD);
-          /* yes, overwrite it. Note in this case we don't
-           * bother to try shrinking the page if the new data
-           * is smaller than the overflow threshold. */
-          if (unlikely(level > 1)) {
-            /* It is writable only in a parent txn */
-            MDBX_page *np = mdbx_page_malloc(mc->mc_txn, ovpages);
-            if (unlikely(!np))
-              return MDBX_ENOMEM;
-            /* Note - this page is already counted in parent's dirtyroom */
-            rc2 = mdbx_dpl_append(mc->mc_txn, pg, np);
-            if (unlikely(rc2 != MDBX_SUCCESS)) {
-              rc = rc2;
-              mdbx_dpage_free(env, np, ovpages);
-              goto fail;
-            }
-
-            /* Currently we make the page look as with put() in the
-             * parent txn, in case the user peeks at MDBX_RESERVEd
-             * or unused parts. Some users treat ovpages specially. */
-            const size_t whole = pgno2bytes(env, ovpages);
-            /* Skip the part where MDBX will put *data.
-             * Copy end of page, adjusting alignment so
-             * compiler may copy words instead of bytes. */
-            const size_t off =
-                (PAGEHDRSZ + data->iov_len) & -(intptr_t)sizeof(size_t);
-            memcpy((size_t *)((char *)np + off), (size_t *)((char *)omp + off),
-                   whole - off);
-            memcpy(np, omp, PAGEHDRSZ); /* Copy header of page */
-            omp = np;
-            mdbx_cassert(mc, mdbx_dirtylist_check(mc->mc_txn));
-          }
-          node_set_ds(node, data->iov_len);
-          if (F_ISSET(flags, MDBX_RESERVE))
-            data->iov_base = page_data(omp);
-          else
-            memcpy(page_data(omp), data->iov_base, data->iov_len);
-
-          if (mdbx_audit_enabled()) {
-            int err = mdbx_cursor_check(mc, 0);
-            if (unlikely(err != MDBX_SUCCESS))
-              return err;
-          }
-          return MDBX_SUCCESS;
-        }
-      }
-      if ((rc2 = mdbx_page_retire(mc, omp)) != MDBX_SUCCESS)
-        return rc2;
-    } else {
-      olddata.iov_len = node_ds(node);
-      olddata.iov_base = node_data(node);
-      mdbx_cassert(mc, (char *)olddata.iov_base + olddata.iov_len <=
-                           (char *)(mc->mc_pg[mc->mc_top]) + env->me_psize);
-
-      /* DB has dups? */
-      if (F_ISSET(mc->mc_db->md_flags, MDBX_DUPSORT)) {
-        /* Prepare (sub-)page/sub-DB to accept the new item, if needed.
-         * fp: old sub-page or a header faking it.
-         * mp: new (sub-)page.  offset: growth in page size.
-         * xdata: node data with new page or DB. */
-        unsigned i;
-        size_t offset = 0;
-        MDBX_page *mp = fp = xdata.iov_base = env->me_pbuf;
-        mp->mp_pgno = mc->mc_pg[mc->mc_top]->mp_pgno;
-
-        /* Was a single item before, must convert now */
-        if (!F_ISSET(node_flags(node), F_DUPDATA)) {
-
-          /* does data match? */
-          const int cmp = mc->mc_dbx->md_dcmp(data, &olddata);
-          if ((flags & MDBX_APPENDDUP) && unlikely(cmp <= 0))
-            return MDBX_EKEYMISMATCH;
-          if (cmp == 0) {
-            if (flags & MDBX_NODUPDATA)
-              return MDBX_KEYEXIST;
-            if (likely(unsure_equal(mc->mc_dbx->md_dcmp, data, &olddata))) {
-              /* data is match exactly byte-to-byte, nothing to update */
-              if (unlikely(flags & MDBX_MULTIPLE)) {
-                rc = MDBX_SUCCESS;
-                goto continue_multiple;
-              }
-              return MDBX_SUCCESS;
-            } else {
-              /* The data has differences, but the user-provided comparator
-               * considers them equal. So continue update since called without.
-               * Continue to update since was called without MDBX_NODUPDATA. */
-            }
-            mdbx_cassert(
-                mc,
-                node_size(key, data) <=
-                    /* See note inside leaf_size() */ env->me_branch_nodemax);
-            goto current;
-          }
-
-          /* Just overwrite the current item */
-          if (flags & MDBX_CURRENT) {
-            mdbx_cassert(
-                mc,
-                node_size(key, data) <=
-                    /* See note inside leaf_size() */ env->me_branch_nodemax);
-            goto current;
-          }
-
-          /* Back up original data item */
-          memcpy(dkey.iov_base = fp + 1, olddata.iov_base,
-                 dkey.iov_len = olddata.iov_len);
-          dupdata_flag = 1;
-
-          /* Make sub-page header for the dup items, with dummy body */
-          fp->mp_flags = P_LEAF | P_DIRTY | P_SUBP;
-          fp->mp_lower = 0;
-          xdata.iov_len = PAGEHDRSZ + dkey.iov_len + data->iov_len;
-          if (mc->mc_db->md_flags & MDBX_DUPFIXED) {
-            fp->mp_flags |= P_LEAF2;
-            fp->mp_leaf2_ksize = (uint16_t)data->iov_len;
-            xdata.iov_len += 2 * data->iov_len; /* leave space for 2 more */
-            mdbx_cassert(mc, xdata.iov_len <= env->me_psize);
-          } else {
-            xdata.iov_len += 2 * (sizeof(indx_t) + NODESIZE) +
-                             (dkey.iov_len & 1) + (data->iov_len & 1);
-            mdbx_cassert(mc, xdata.iov_len <= env->me_psize);
-          }
-          fp->mp_upper = (uint16_t)(xdata.iov_len - PAGEHDRSZ);
-          olddata.iov_len = xdata.iov_len; /* pretend olddata is fp */
-        } else if (node_flags(node) & F_SUBDATA) {
-          /* Data is on sub-DB, just store it */
-          flags |= F_DUPDATA | F_SUBDATA;
-          goto put_sub;
-        } else {
-          /* Data is on sub-page */
-          fp = olddata.iov_base;
-          switch (flags) {
-          default:
-            if (!(mc->mc_db->md_flags & MDBX_DUPFIXED)) {
-              offset = node_size(data, nullptr) + sizeof(indx_t);
-              break;
-            }
-            offset = fp->mp_leaf2_ksize;
-            if (page_room(fp) < offset) {
-              offset *= 4; /* space for 4 more */
-              break;
-            }
-            /* FALLTHRU: Big enough MDBX_DUPFIXED sub-page */
-            __fallthrough;
-          case MDBX_CURRENT | MDBX_NODUPDATA:
-          case MDBX_CURRENT:
-            fp->mp_flags |= P_DIRTY;
-            fp->mp_txnid = INVALID_TXNID;
-            fp->mp_pgno = mp->mp_pgno;
-            mc->mc_xcursor->mx_cursor.mc_pg[0] = fp;
-            flags |= F_DUPDATA;
-            goto put_sub;
-          }
-          xdata.iov_len = olddata.iov_len + offset;
-        }
-
-        fp_flags = fp->mp_flags;
-        if (NODESIZE + node_ks(node) + xdata.iov_len >
-            /* See note inside leaf_size() */ env->me_branch_nodemax) {
-          /* Too big for a sub-page, convert to sub-DB */
-          fp_flags &= ~P_SUBP;
-        prep_subDB:
-          nested_dupdb.md_xsize = 0;
-          nested_dupdb.md_flags = flags_db2sub(mc->mc_db->md_flags);
-          if (mc->mc_db->md_flags & MDBX_DUPFIXED) {
-            fp_flags |= P_LEAF2;
-            nested_dupdb.md_xsize = fp->mp_leaf2_ksize;
-          }
-          nested_dupdb.md_depth = 1;
-          nested_dupdb.md_branch_pages = 0;
-          nested_dupdb.md_leaf_pages = 1;
-          nested_dupdb.md_overflow_pages = 0;
-          nested_dupdb.md_entries = page_numkeys(fp);
-          xdata.iov_len = sizeof(nested_dupdb);
-          xdata.iov_base = &nested_dupdb;
-          if ((rc2 = mdbx_page_alloc(mc, 1, &mp, MDBX_ALLOC_ALL)))
-            return rc2;
-          mc->mc_db->md_leaf_pages += 1;
-          mdbx_cassert(mc, env->me_psize > olddata.iov_len);
-          offset = env->me_psize - (unsigned)olddata.iov_len;
-          flags |= F_DUPDATA | F_SUBDATA;
-          nested_dupdb.md_root = mp->mp_pgno;
-          nested_dupdb.md_seq = 0;
-          nested_dupdb.md_mod_txnid = pp_txnid2chk(mc->mc_txn);
-          sub_root = mp;
-        }
-        if (mp != fp) {
-          mp->mp_flags = fp_flags | P_DIRTY;
-          mp->mp_txnid = INVALID_TXNID;
-          mp->mp_leaf2_ksize = fp->mp_leaf2_ksize;
-          mp->mp_lower = fp->mp_lower;
-          mdbx_cassert(mc, fp->mp_upper + offset <= UINT16_MAX);
-          mp->mp_upper = (indx_t)(fp->mp_upper + offset);
-          if (unlikely(fp_flags & P_LEAF2)) {
-            memcpy(page_data(mp), page_data(fp),
-                   page_numkeys(fp) * fp->mp_leaf2_ksize);
-          } else {
-            memcpy((char *)mp + mp->mp_upper + PAGEHDRSZ,
-                   (char *)fp + fp->mp_upper + PAGEHDRSZ,
-                   olddata.iov_len - fp->mp_upper - PAGEHDRSZ);
-            memcpy((char *)(&mp->mp_ptrs), (char *)(&fp->mp_ptrs),
-                   page_numkeys(fp) * sizeof(mp->mp_ptrs[0]));
-            for (i = 0; i < page_numkeys(fp); i++) {
-              mdbx_cassert(mc, mp->mp_ptrs[i] + offset <= UINT16_MAX);
-              mp->mp_ptrs[i] += (indx_t)offset;
-            }
-          }
-        }
-
-        rdata = &xdata;
-        flags |= F_DUPDATA;
-        do_sub = true;
-        if (!insert_key)
-          mdbx_node_del(mc, 0);
-        goto new_sub;
-      }
-
-      /* MDBX passes F_SUBDATA in 'flags' to write a DB record */
-      if (unlikely((node_flags(node) ^ flags) & F_SUBDATA))
-        return MDBX_INCOMPATIBLE;
-
-    current:
-      if (data->iov_len == olddata.iov_len) {
-        mdbx_cassert(mc, EVEN(key->iov_len) == EVEN(node_ks(node)));
-        /* same size, just replace it. Note that we could
-         * also reuse this node if the new data is smaller,
-         * but instead we opt to shrink the node in that case. */
-        if (F_ISSET(flags, MDBX_RESERVE))
-          data->iov_base = olddata.iov_base;
-        else if (!(mc->mc_flags & C_SUB))
-          memcpy(olddata.iov_base, data->iov_base, data->iov_len);
-        else {
-          mdbx_cassert(mc, page_numkeys(mc->mc_pg[mc->mc_top]) == 1);
-          mdbx_cassert(mc, PAGETYPE(mc->mc_pg[mc->mc_top]) == P_LEAF);
-          mdbx_cassert(mc, node_ds(node) == 0);
-          mdbx_cassert(mc, node_flags(node) == 0);
-          mdbx_cassert(mc, key->iov_len < UINT16_MAX);
-          node_set_ks(node, key->iov_len);
-          memcpy(node_key(node), key->iov_base, key->iov_len);
-          mdbx_cassert(mc, (char *)node_key(node) + node_ds(node) <
-                               (char *)(mc->mc_pg[mc->mc_top]) + env->me_psize);
-          goto fix_parent;
-        }
-
-        if (mdbx_audit_enabled()) {
-          int err = mdbx_cursor_check(mc, 0);
-          if (unlikely(err != MDBX_SUCCESS))
-            return err;
-        }
-        return MDBX_SUCCESS;
-      }
-    }
-    mdbx_node_del(mc, 0);
-  }
-
-  rdata = data;
-
-new_sub:;
-  unsigned nflags = flags & NODE_ADD_FLAGS;
-  size_t nsize = IS_LEAF2(mc->mc_pg[mc->mc_top]) ? key->iov_len
-                                                 : leaf_size(env, key, rdata);
-  if (page_room(mc->mc_pg[mc->mc_top]) < nsize) {
-    if ((flags & (F_DUPDATA | F_SUBDATA)) == F_DUPDATA)
-      nflags &= ~MDBX_APPEND; /* sub-page may need room to grow */
-    if (!insert_key)
-      nflags |= MDBX_SPLIT_REPLACE;
-    rc = mdbx_page_split(mc, key, rdata, P_INVALID, nflags);
-    if (rc == MDBX_SUCCESS && mdbx_audit_enabled())
-      rc = mdbx_cursor_check(mc, 0);
-  } else {
-    /* There is room already in this leaf page. */
-    if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
-      mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0 &&
-                           rdata->iov_len == 0);
-      rc = mdbx_node_add_leaf2(mc, mc->mc_ki[mc->mc_top], key);
-    } else
-      rc = mdbx_node_add_leaf(mc, mc->mc_ki[mc->mc_top], key, rdata, nflags);
-    if (likely(rc == 0)) {
-      /* Adjust other cursors pointing to mp */
-      const MDBX_dbi dbi = mc->mc_dbi;
-      const unsigned i = mc->mc_top;
-      MDBX_page *const mp = mc->mc_pg[i];
-      for (MDBX_cursor *m2 = mc->mc_txn->tw.cursors[dbi]; m2;
-           m2 = m2->mc_next) {
-        MDBX_cursor *m3 =
-            (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-        if (m3 == mc || m3->mc_snum < mc->mc_snum || m3->mc_pg[i] != mp)
-          continue;
-        if (m3->mc_ki[i] >= mc->mc_ki[i])
-          m3->mc_ki[i] += insert_key;
-        if (XCURSOR_INITED(m3))
-          XCURSOR_REFRESH(m3, mp, m3->mc_ki[i]);
-      }
-    }
-  }
-
-  if (likely(rc == MDBX_SUCCESS)) {
-    /* Now store the actual data in the child DB. Note that we're
-     * storing the user data in the keys field, so there are strict
-     * size limits on dupdata. The actual data fields of the child
-     * DB are all zero size. */
-    if (do_sub) {
-      int xflags;
-      size_t ecount;
-    put_sub:
-      xdata.iov_len = 0;
-      xdata.iov_base = nullptr;
-      MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-#define SHIFT_MDBX_NODUPDATA_TO_MDBX_NOOVERWRITE 1
-      STATIC_ASSERT(
-          (MDBX_NODUPDATA >> SHIFT_MDBX_NODUPDATA_TO_MDBX_NOOVERWRITE) ==
-          MDBX_NOOVERWRITE);
-      xflags = MDBX_CURRENT | MDBX_NOSPILL |
-               ((flags & MDBX_NODUPDATA) >>
-                SHIFT_MDBX_NODUPDATA_TO_MDBX_NOOVERWRITE);
-      if ((flags & MDBX_CURRENT) == 0) {
-        xflags -= MDBX_CURRENT;
-        rc2 = mdbx_xcursor_init1(mc, node, mc->mc_pg[mc->mc_top]);
-        if (unlikely(rc2 != MDBX_SUCCESS))
-          return rc2;
-      }
-      if (sub_root)
-        mc->mc_xcursor->mx_cursor.mc_pg[0] = sub_root;
-      /* converted, write the original data first */
-      if (dupdata_flag) {
-        rc = mdbx_cursor_put(&mc->mc_xcursor->mx_cursor, &dkey, &xdata, xflags);
-        if (unlikely(rc))
-          goto bad_sub;
-        /* we've done our job */
-        dkey.iov_len = 0;
-      }
-      if (!(node_flags(node) & F_SUBDATA) || sub_root) {
-        /* Adjust other cursors pointing to mp */
-        MDBX_cursor *m2;
-        MDBX_xcursor *mx = mc->mc_xcursor;
-        unsigned i = mc->mc_top;
-        MDBX_page *mp = mc->mc_pg[i];
-        const int nkeys = page_numkeys(mp);
-
-        for (m2 = mc->mc_txn->tw.cursors[mc->mc_dbi]; m2; m2 = m2->mc_next) {
-          if (m2 == mc || m2->mc_snum < mc->mc_snum)
-            continue;
-          if (!(m2->mc_flags & C_INITIALIZED))
-            continue;
-          if (m2->mc_pg[i] == mp) {
-            if (m2->mc_ki[i] == mc->mc_ki[i]) {
-              rc2 = mdbx_xcursor_init2(m2, mx, dupdata_flag);
-              if (unlikely(rc2 != MDBX_SUCCESS))
-                return rc2;
-            } else if (!insert_key && m2->mc_ki[i] < nkeys) {
-              XCURSOR_REFRESH(m2, mp, m2->mc_ki[i]);
-            }
-          }
-        }
-      }
-      mdbx_cassert(mc, mc->mc_xcursor->mx_db.md_entries < PTRDIFF_MAX);
-      ecount = (size_t)mc->mc_xcursor->mx_db.md_entries;
-#define SHIFT_MDBX_APPENDDUP_TO_MDBX_APPEND 1
-      STATIC_ASSERT((MDBX_APPENDDUP >> SHIFT_MDBX_APPENDDUP_TO_MDBX_APPEND) ==
-                    MDBX_APPEND);
-      xflags |= (flags & MDBX_APPENDDUP) >> SHIFT_MDBX_APPENDDUP_TO_MDBX_APPEND;
-      rc = mdbx_cursor_put(&mc->mc_xcursor->mx_cursor, data, &xdata, xflags);
-      if (flags & F_SUBDATA) {
-        void *db = node_data(node);
-        mc->mc_xcursor->mx_db.md_mod_txnid = pp_txnid2chk(mc->mc_txn);
-        memcpy(db, &mc->mc_xcursor->mx_db, sizeof(MDBX_db));
-      }
-      insert_data = (ecount != (size_t)mc->mc_xcursor->mx_db.md_entries);
-    }
-    /* Increment count unless we just replaced an existing item. */
-    if (insert_data)
-      mc->mc_db->md_entries++;
-    if (insert_key) {
-      /* Invalidate txn if we created an empty sub-DB */
-      if (unlikely(rc))
-        goto bad_sub;
-      /* If we succeeded and the key didn't exist before,
-       * make sure the cursor is marked valid. */
-      mc->mc_flags |= C_INITIALIZED;
-    }
-    if (flags & MDBX_MULTIPLE) {
-      if (!rc) {
-      continue_multiple:
-        mcount++;
-        /* let caller know how many succeeded, if any */
-        data[1].iov_len = mcount;
-        if (mcount < dcount) {
-          data[0].iov_base = (char *)data[0].iov_base + data[0].iov_len;
-          insert_key = insert_data = false;
-          goto more;
-        }
-      }
-    }
-    if (rc == MDBX_SUCCESS && mdbx_audit_enabled())
-      rc = mdbx_cursor_check(mc, 0);
-    return rc;
-  bad_sub:
-    if (unlikely(rc == MDBX_KEYEXIST))
-      mdbx_error("unexpected %s", "MDBX_KEYEXIST");
-    /* should not happen, we deleted that item */
-    rc = MDBX_PROBLEM;
-  }
-fail:
-  mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-  return rc;
-}
-
-int mdbx_cursor_del(MDBX_cursor *mc, MDBX_put_flags_t flags) {
-  if (unlikely(!mc))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  int rc = check_txn_rw(mc->mc_txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(!(mc->mc_flags & C_INITIALIZED)))
-    return MDBX_ENODATA;
-
-  if (unlikely(mc->mc_ki[mc->mc_top] >= page_numkeys(mc->mc_pg[mc->mc_top])))
-    return MDBX_NOTFOUND;
-
-  if (unlikely(!(flags & MDBX_NOSPILL) &&
-               (rc = mdbx_cursor_spill(mc, NULL, NULL))))
-    return rc;
-
-  rc = mdbx_cursor_touch(mc);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  if (unlikely(!IS_LEAF(mp)))
-    return MDBX_CORRUPTED;
-  if (IS_LEAF2(mp))
-    goto del_key;
-
-  MDBX_node *node = page_node(mp, mc->mc_ki[mc->mc_top]);
-  if (F_ISSET(node_flags(node), F_DUPDATA)) {
-    if (flags & (MDBX_ALLDUPS | /* for compatibility */ MDBX_NODUPDATA)) {
-      /* mdbx_cursor_del0() will subtract the final entry */
-      mc->mc_db->md_entries -= mc->mc_xcursor->mx_db.md_entries - 1;
-      mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
-    } else {
-      if (!F_ISSET(node_flags(node), F_SUBDATA))
-        mc->mc_xcursor->mx_cursor.mc_pg[0] = node_data(node);
-      rc = mdbx_cursor_del(&mc->mc_xcursor->mx_cursor, MDBX_NOSPILL);
-      if (unlikely(rc))
-        return rc;
-      /* If sub-DB still has entries, we're done */
-      if (mc->mc_xcursor->mx_db.md_entries) {
-        if (node_flags(node) & F_SUBDATA) {
-          /* update subDB info */
-          void *db = node_data(node);
-          mc->mc_xcursor->mx_db.md_mod_txnid = pp_txnid2chk(mc->mc_txn);
-          memcpy(db, &mc->mc_xcursor->mx_db, sizeof(MDBX_db));
-        } else {
-          MDBX_cursor *m2;
-          /* shrink fake page */
-          mdbx_node_shrink(mp, mc->mc_ki[mc->mc_top]);
-          node = page_node(mp, mc->mc_ki[mc->mc_top]);
-          mc->mc_xcursor->mx_cursor.mc_pg[0] = node_data(node);
-          /* fix other sub-DB cursors pointed at fake pages on this page */
-          for (m2 = mc->mc_txn->tw.cursors[mc->mc_dbi]; m2; m2 = m2->mc_next) {
-            if (m2 == mc || m2->mc_snum < mc->mc_snum)
-              continue;
-            if (!(m2->mc_flags & C_INITIALIZED))
-              continue;
-            if (m2->mc_pg[mc->mc_top] == mp) {
-              MDBX_node *inner = node;
-              if (m2->mc_ki[mc->mc_top] >= page_numkeys(mp))
-                continue;
-              if (m2->mc_ki[mc->mc_top] != mc->mc_ki[mc->mc_top]) {
-                inner = page_node(mp, m2->mc_ki[mc->mc_top]);
-                if (node_flags(inner) & F_SUBDATA)
-                  continue;
-              }
-              m2->mc_xcursor->mx_cursor.mc_pg[0] = node_data(inner);
-            }
-          }
-        }
-        mc->mc_db->md_entries--;
-        mdbx_cassert(mc, mc->mc_db->md_entries > 0 && mc->mc_db->md_depth > 0 &&
-                             mc->mc_db->md_root != P_INVALID);
-        return rc;
-      } else {
-        mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
-      }
-      /* otherwise fall thru and delete the sub-DB */
-    }
-
-    if (node_flags(node) & F_SUBDATA) {
-      /* add all the child DB's pages to the free list */
-      rc = mdbx_drop0(&mc->mc_xcursor->mx_cursor, 0);
-      if (unlikely(rc))
-        goto fail;
-    }
-  }
-  /* MDBX passes F_SUBDATA in 'flags' to delete a DB record */
-  else if (unlikely((node_flags(node) ^ flags) & F_SUBDATA))
-    return MDBX_INCOMPATIBLE;
-
-  /* add overflow pages to free list */
-  if (F_ISSET(node_flags(node), F_BIGDATA)) {
-    MDBX_page *omp;
-    if (unlikely((rc = mdbx_page_get(mc, node_largedata_pgno(node), &omp, NULL,
-                                     pp_txnid4chk(mp, mc->mc_txn))) ||
-                 (rc = mdbx_page_retire(mc, omp))))
-      goto fail;
-  }
-
-del_key:
-  return mdbx_cursor_del0(mc);
-
-fail:
-  mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-  return rc;
-}
-
-/* Allocate and initialize new pages for a database.
- * Set MDBX_TXN_ERROR on failure.
- *
- * [in] mc a  cursor on the database being added to.
- * [in] flags flags defining what type of page is being allocated.
- * [in] num   the number of pages to allocate. This is usually 1,
- *            unless allocating overflow pages for a large record.
- * [out] mp   Address of a page, or NULL on failure.
- *
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_page_new(MDBX_cursor *mc, unsigned flags, unsigned num,
-                         MDBX_page **mp) {
-  MDBX_page *np;
-  int rc;
-
-  if (unlikely((rc = mdbx_page_alloc(mc, num, &np, MDBX_ALLOC_ALL))))
-    return rc;
-  *mp = np;
-  mdbx_debug("db %u allocated new page %" PRIaPGNO ", num %u", mc->mc_dbi,
-             np->mp_pgno, num);
-  np->mp_flags = (uint16_t)(flags | P_DIRTY);
-  np->mp_txnid = INVALID_TXNID;
-  np->mp_lower = 0;
-  np->mp_upper = (indx_t)(mc->mc_txn->mt_env->me_psize - PAGEHDRSZ);
-
-  *mc->mc_dbistate |= DBI_DIRTY;
-  mc->mc_txn->mt_flags |= MDBX_TXN_DIRTY;
-  mc->mc_db->md_branch_pages += IS_BRANCH(np);
-  mc->mc_db->md_leaf_pages += IS_LEAF(np);
-  if (unlikely(IS_OVERFLOW(np))) {
-    mc->mc_db->md_overflow_pages += num;
-    np->mp_pages = num;
-    mdbx_cassert(mc, !(mc->mc_flags & C_SUB));
-  } else if (unlikely(mc->mc_flags & C_SUB)) {
-    MDBX_db *outer = mdbx_outer_db(mc);
-    outer->md_branch_pages += IS_BRANCH(np);
-    outer->md_leaf_pages += IS_LEAF(np);
-  }
-
-  return MDBX_SUCCESS;
-}
-
-static int __must_check_result mdbx_node_add_leaf2(MDBX_cursor *mc,
-                                                   unsigned indx,
-                                                   const MDBX_val *key) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  DKBUF;
-  mdbx_debug("add to leaf2-%spage %" PRIaPGNO " index %i, "
-             " key size %" PRIuPTR " [%s]",
-             IS_SUBP(mp) ? "sub-" : "", mp->mp_pgno, indx,
-             key ? key->iov_len : 0, DKEY(key));
-
-  mdbx_cassert(mc, key);
-  mdbx_cassert(mc, PAGETYPE(mp) == (P_LEAF | P_LEAF2));
-  const unsigned ksize = mc->mc_db->md_xsize;
-  mdbx_cassert(mc, ksize == key->iov_len);
-  const unsigned nkeys = page_numkeys(mp);
-
-  /* Just using these for counting */
-  const intptr_t lower = mp->mp_lower + sizeof(indx_t);
-  const intptr_t upper = mp->mp_upper - (ksize - sizeof(indx_t));
-  if (unlikely(lower > upper)) {
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-    return MDBX_PAGE_FULL;
-  }
-  mp->mp_lower = (indx_t)lower;
-  mp->mp_upper = (indx_t)upper;
-
-  char *const ptr = page_leaf2key(mp, indx, ksize);
-  mdbx_cassert(mc, nkeys >= indx);
-  const unsigned diff = nkeys - indx;
-  if (likely(diff > 0))
-    /* Move higher keys up one slot. */
-    memmove(ptr + ksize, ptr, diff * ksize);
-  /* insert new key */
-  memcpy(ptr, key->iov_base, ksize);
-  return MDBX_SUCCESS;
-}
-
-static int __must_check_result mdbx_node_add_branch(MDBX_cursor *mc,
-                                                    unsigned indx,
-                                                    const MDBX_val *key,
-                                                    pgno_t pgno) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  DKBUF;
-  mdbx_debug("add to branch-%spage %" PRIaPGNO " index %i, node-pgno %" PRIaPGNO
-             " key size %" PRIuPTR " [%s]",
-             IS_SUBP(mp) ? "sub-" : "", mp->mp_pgno, indx, pgno,
-             key ? key->iov_len : 0, DKEY(key));
-
-  mdbx_cassert(mc, PAGETYPE(mp) == P_BRANCH);
-  STATIC_ASSERT(NODESIZE % 2 == 0);
-
-  /* Move higher pointers up one slot. */
-  const unsigned nkeys = page_numkeys(mp);
-  mdbx_cassert(mc, nkeys >= indx);
-  for (unsigned i = nkeys; i > indx; --i)
-    mp->mp_ptrs[i] = mp->mp_ptrs[i - 1];
-
-  /* Adjust free space offsets. */
-  const size_t branch_bytes = branch_size(mc->mc_txn->mt_env, key);
-  const intptr_t lower = mp->mp_lower + sizeof(indx_t);
-  const intptr_t upper = mp->mp_upper - (branch_bytes - sizeof(indx_t));
-  if (unlikely(lower > upper)) {
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-    return MDBX_PAGE_FULL;
-  }
-  mp->mp_lower = (indx_t)lower;
-  mp->mp_ptrs[indx] = mp->mp_upper = (indx_t)upper;
-
-  /* Write the node data. */
-  MDBX_node *node = page_node(mp, indx);
-  node_set_pgno(node, pgno);
-  node_set_flags(node, 0);
-  UNALIGNED_POKE_8(node, MDBX_node, mn_extra, 0);
-  node_set_ks(node, 0);
-  if (likely(key != NULL)) {
-    node_set_ks(node, key->iov_len);
-    memcpy(node_key(node), key->iov_base, key->iov_len);
-  }
-  return MDBX_SUCCESS;
-}
-
-static int __must_check_result mdbx_node_add_leaf(MDBX_cursor *mc,
-                                                  unsigned indx,
-                                                  const MDBX_val *key,
-                                                  MDBX_val *data,
-                                                  unsigned flags) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  DKBUF;
-  mdbx_debug("add to leaf-%spage %" PRIaPGNO " index %i, data size %" PRIuPTR
-             " key size %" PRIuPTR " [%s]",
-             IS_SUBP(mp) ? "sub-" : "", mp->mp_pgno, indx,
-             data ? data->iov_len : 0, key ? key->iov_len : 0, DKEY(key));
-  mdbx_cassert(mc, key != NULL && data != NULL);
-  mdbx_cassert(mc, PAGETYPE(mp) == P_LEAF);
-  MDBX_page *largepage = NULL;
-
-  size_t leaf_bytes;
-  if (unlikely(flags & F_BIGDATA)) {
-    /* Data already on overflow page. */
-    STATIC_ASSERT(sizeof(pgno_t) % 2 == 0);
-    leaf_bytes = node_size(key, nullptr) + sizeof(pgno_t) + sizeof(indx_t);
-  } else if (unlikely(node_size(key, data) >
-                      /* See note inside leaf_size() */
-                      mc->mc_txn->mt_env->me_branch_nodemax)) {
-    /* Put data on overflow page. */
-    mdbx_ensure(mc->mc_txn->mt_env,
-                !F_ISSET(mc->mc_db->md_flags, MDBX_DUPSORT));
-    if (unlikely(flags & (F_DUPDATA | F_SUBDATA)))
-      return MDBX_PROBLEM;
-    const pgno_t ovpages = number_of_ovpages(mc->mc_txn->mt_env, data->iov_len);
-    int rc = mdbx_page_new(mc, P_OVERFLOW, ovpages, &largepage);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    mdbx_debug("allocated %u overflow page(s) %" PRIaPGNO "for %" PRIuPTR
-               " data bytes",
-               largepage->mp_pages, largepage->mp_pgno, data->iov_len);
-    flags |= F_BIGDATA;
-    leaf_bytes = node_size(key, nullptr) + sizeof(pgno_t) + sizeof(indx_t);
-  } else {
-    leaf_bytes = node_size(key, data) + sizeof(indx_t);
-  }
-  mdbx_cassert(mc, leaf_bytes == leaf_size(mc->mc_txn->mt_env, key, data));
-
-  /* Move higher pointers up one slot. */
-  const unsigned nkeys = page_numkeys(mp);
-  mdbx_cassert(mc, nkeys >= indx);
-  for (unsigned i = nkeys; i > indx; --i)
-    mp->mp_ptrs[i] = mp->mp_ptrs[i - 1];
-
-  /* Adjust free space offsets. */
-  const intptr_t lower = mp->mp_lower + sizeof(indx_t);
-  const intptr_t upper = mp->mp_upper - (leaf_bytes - sizeof(indx_t));
-  if (unlikely(lower > upper)) {
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-    return MDBX_PAGE_FULL;
-  }
-  mp->mp_lower = (indx_t)lower;
-  mp->mp_ptrs[indx] = mp->mp_upper = (indx_t)upper;
-
-  /* Write the node data. */
-  MDBX_node *node = page_node(mp, indx);
-  node_set_ks(node, key->iov_len);
-  node_set_flags(node, (uint8_t)flags);
-  UNALIGNED_POKE_8(node, MDBX_node, mn_extra, 0);
-  node_set_ds(node, data->iov_len);
-  memcpy(node_key(node), key->iov_base, key->iov_len);
-
-  void *nodedata = node_data(node);
-  if (likely(largepage == NULL)) {
-    if (unlikely(flags & F_BIGDATA))
-      memcpy(nodedata, data->iov_base, sizeof(pgno_t));
-    else if (unlikely(flags & MDBX_RESERVE))
-      data->iov_base = nodedata;
-    else if (likely(nodedata != data->iov_base &&
-                    data->iov_len /* to avoid UBSAN traps*/ != 0))
-      memcpy(nodedata, data->iov_base, data->iov_len);
-  } else {
-    poke_pgno(nodedata, largepage->mp_pgno);
-    nodedata = page_data(largepage);
-    if (unlikely(flags & MDBX_RESERVE))
-      data->iov_base = nodedata;
-    else if (likely(nodedata != data->iov_base &&
-                    data->iov_len /* to avoid UBSAN traps*/ != 0))
-      memcpy(nodedata, data->iov_base, data->iov_len);
-  }
-  return MDBX_SUCCESS;
-}
-
-/* Delete the specified node from a page.
- * [in] mc Cursor pointing to the node to delete.
- * [in] ksize The size of a node. Only used if the page is
- * part of a MDBX_DUPFIXED database. */
-static void mdbx_node_del(MDBX_cursor *mc, size_t ksize) {
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  int indx = mc->mc_ki[mc->mc_top];
-  int i, j, nkeys, ptr;
-  MDBX_node *node;
-  char *base;
-
-  mdbx_debug("delete node %u on %s page %" PRIaPGNO, indx,
-             IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno);
-  nkeys = page_numkeys(mp);
-  mdbx_cassert(mc, indx < nkeys);
-
-  if (IS_LEAF2(mp)) {
-    mdbx_cassert(mc, ksize >= sizeof(indx_t));
-    unsigned diff = nkeys - 1 - indx;
-    base = page_leaf2key(mp, indx, ksize);
-    if (diff)
-      memmove(base, base + ksize, diff * ksize);
-    mdbx_cassert(mc, mp->mp_lower >= sizeof(indx_t));
-    mp->mp_lower -= sizeof(indx_t);
-    mdbx_cassert(mc,
-                 (size_t)UINT16_MAX - mp->mp_upper >= ksize - sizeof(indx_t));
-    mp->mp_upper += (indx_t)(ksize - sizeof(indx_t));
-    return;
-  }
-
-  node = page_node(mp, indx);
-  size_t sz = NODESIZE + node_ks(node);
-  if (IS_LEAF(mp)) {
-    if (F_ISSET(node_flags(node), F_BIGDATA))
-      sz += sizeof(pgno_t);
-    else
-      sz += node_ds(node);
-  }
-  sz = EVEN(sz);
-
-  ptr = mp->mp_ptrs[indx];
-  for (i = j = 0; i < nkeys; i++) {
-    if (i != indx) {
-      mp->mp_ptrs[j] = mp->mp_ptrs[i];
-      if (mp->mp_ptrs[i] < ptr) {
-        mdbx_cassert(mc, (size_t)UINT16_MAX - mp->mp_ptrs[j] >= sz);
-        mp->mp_ptrs[j] += (indx_t)sz;
-      }
-      j++;
-    }
-  }
-
-  base = (char *)mp + mp->mp_upper + PAGEHDRSZ;
-  memmove(base + sz, base, ptr - mp->mp_upper);
-
-  mdbx_cassert(mc, mp->mp_lower >= sizeof(indx_t));
-  mp->mp_lower -= sizeof(indx_t);
-  mdbx_cassert(mc, (size_t)UINT16_MAX - mp->mp_upper >= sz);
-  mp->mp_upper += (indx_t)sz;
-
-#if MDBX_DEBUG > 0
-  if (mdbx_audit_enabled()) {
-    int page_check_err = mdbx_page_check(mc, mp, C_UPDATING);
-    mdbx_cassert(mc, page_check_err == MDBX_SUCCESS);
-  }
-#endif
-}
-
-/* Compact the main page after deleting a node on a subpage.
- * [in] mp The main page to operate on.
- * [in] indx The index of the subpage on the main page. */
-static void mdbx_node_shrink(MDBX_page *mp, unsigned indx) {
-  MDBX_node *node;
-  MDBX_page *sp, *xp;
-  char *base;
-  size_t nsize, delta, len, ptr;
-  int i;
-
-  node = page_node(mp, indx);
-  sp = (MDBX_page *)node_data(node);
-  delta = page_room(sp);
-  assert(delta > 0);
-
-  /* Prepare to shift upward, set len = length(subpage part to shift) */
-  if (IS_LEAF2(sp)) {
-    delta &= /* do not make the node uneven-sized */ ~(size_t)1;
-    if (unlikely(delta) == 0)
-      return;
-    nsize = node_ds(node) - delta;
-    assert(nsize % 1 == 0);
-    len = nsize;
-  } else {
-    xp = (MDBX_page *)((char *)sp + delta); /* destination subpage */
-    for (i = page_numkeys(sp); --i >= 0;) {
-      assert(sp->mp_ptrs[i] >= delta);
-      xp->mp_ptrs[i] = (indx_t)(sp->mp_ptrs[i] - delta);
-    }
-    nsize = node_ds(node) - delta;
-    len = PAGEHDRSZ;
-  }
-  sp->mp_upper = sp->mp_lower;
-  sp->mp_pgno = mp->mp_pgno;
-  node_set_ds(node, nsize);
-
-  /* Shift <lower nodes...initial part of subpage> upward */
-  base = (char *)mp + mp->mp_upper + PAGEHDRSZ;
-  memmove(base + delta, base, (char *)sp + len - base);
-
-  ptr = mp->mp_ptrs[indx];
-  for (i = page_numkeys(mp); --i >= 0;) {
-    if (mp->mp_ptrs[i] <= ptr) {
-      assert((size_t)UINT16_MAX - mp->mp_ptrs[i] >= delta);
-      mp->mp_ptrs[i] += (indx_t)delta;
-    }
-  }
-  assert((size_t)UINT16_MAX - mp->mp_upper >= delta);
-  mp->mp_upper += (indx_t)delta;
-}
-
-/* Initial setup of a sorted-dups cursor.
- *
- * Sorted duplicates are implemented as a sub-database for the given key.
- * The duplicate data items are actually keys of the sub-database.
- * Operations on the duplicate data items are performed using a sub-cursor
- * initialized when the sub-database is first accessed. This function does
- * the preliminary setup of the sub-cursor, filling in the fields that
- * depend only on the parent DB.
- *
- * [in] mc The main cursor whose sorted-dups cursor is to be initialized. */
-static int mdbx_xcursor_init0(MDBX_cursor *mc) {
-  MDBX_xcursor *mx = mc->mc_xcursor;
-  if (unlikely(mx == nullptr)) {
-    mdbx_error("unexpected dupsort-page for non-dupsort db/cursor (dbi %u)",
-               mc->mc_dbi);
-    return MDBX_CORRUPTED;
-  }
-
-  mx->mx_cursor.mc_xcursor = NULL;
-  mx->mx_cursor.mc_txn = mc->mc_txn;
-  mx->mx_cursor.mc_db = &mx->mx_db;
-  mx->mx_cursor.mc_dbx = &mx->mx_dbx;
-  mx->mx_cursor.mc_dbi = mc->mc_dbi;
-  mx->mx_cursor.mc_dbistate = &mx->mx_dbistate;
-  mx->mx_cursor.mc_snum = 0;
-  mx->mx_cursor.mc_top = 0;
-  mx->mx_cursor.mc_flags = C_SUB | (mc->mc_flags & (C_COPYING | C_SKIPORD));
-  mx->mx_dbx.md_name.iov_len = 0;
-  mx->mx_dbx.md_name.iov_base = NULL;
-  mx->mx_dbx.md_cmp = mc->mc_dbx->md_dcmp;
-  mx->mx_dbx.md_dcmp = NULL;
-  mx->mx_dbx.md_klen_min = INT_MAX;
-  mx->mx_dbx.md_vlen_min = mx->mx_dbx.md_klen_max = mx->mx_dbx.md_vlen_max = 0;
-  return MDBX_SUCCESS;
-}
-
-/* Final setup of a sorted-dups cursor.
- * Sets up the fields that depend on the data from the main cursor.
- * [in] mc The main cursor whose sorted-dups cursor is to be initialized.
- * [in] node The data containing the MDBX_db record for the sorted-dup database.
- */
-static int mdbx_xcursor_init1(MDBX_cursor *mc, MDBX_node *node,
-                              const MDBX_page *mp) {
-  MDBX_xcursor *mx = mc->mc_xcursor;
-  if (unlikely(mx == nullptr)) {
-    mdbx_error("unexpected dupsort-page for non-dupsort db/cursor (dbi %u)",
-               mc->mc_dbi);
-    return MDBX_CORRUPTED;
-  }
-
-  const uint8_t flags = node_flags(node);
-  switch (flags) {
-  default:
-    mdbx_error("invalid node flags %u", flags);
-    return MDBX_CORRUPTED;
-  case F_DUPDATA | F_SUBDATA:
-    if (unlikely(node_ds(node) != sizeof(MDBX_db))) {
-      mdbx_error("invalid nested-db record size %zu", node_ds(node));
-      return MDBX_CORRUPTED;
-    }
-    memcpy(&mx->mx_db, node_data(node), sizeof(MDBX_db));
-    const txnid_t pp_txnid = IS_DIRTY(mp) ? mc->mc_txn->mt_txnid : mp->mp_txnid;
-    if (unlikely(mx->mx_db.md_mod_txnid > pp_txnid)) {
-      mdbx_error("nested-db.md_mod_txnid (%" PRIaTXN ") > page-txnid (%" PRIaTXN
-                 ")",
-                 mx->mx_db.md_mod_txnid, pp_txnid);
-      return MDBX_CORRUPTED;
-    }
-    mx->mx_cursor.mc_pg[0] = 0;
-    mx->mx_cursor.mc_snum = 0;
-    mx->mx_cursor.mc_top = 0;
-    mx->mx_cursor.mc_flags = C_SUB | (mc->mc_flags & (C_COPYING | C_SKIPORD));
-    break;
-  case F_DUPDATA:
-    if (unlikely(node_ds(node) <= PAGEHDRSZ)) {
-      mdbx_error("invalid nested-page size %zu", node_ds(node));
-      return MDBX_CORRUPTED;
-    }
-    MDBX_page *fp = node_data(node);
-    mx->mx_db.md_depth = 1;
-    mx->mx_db.md_branch_pages = 0;
-    mx->mx_db.md_leaf_pages = 1;
-    mx->mx_db.md_overflow_pages = 0;
-    mx->mx_db.md_entries = page_numkeys(fp);
-    mx->mx_db.md_root = fp->mp_pgno;
-    mx->mx_db.md_mod_txnid = mp->mp_txnid;
-    mx->mx_cursor.mc_snum = 1;
-    mx->mx_cursor.mc_top = 0;
-    mx->mx_cursor.mc_flags =
-        C_INITIALIZED | C_SUB | (mc->mc_flags & (C_COPYING | C_SKIPORD));
-    mx->mx_cursor.mc_pg[0] = fp;
-    mx->mx_cursor.mc_ki[0] = 0;
-    mx->mx_db.md_flags = flags_db2sub(mc->mc_db->md_flags);
-    mx->mx_db.md_xsize =
-        (mc->mc_db->md_flags & MDBX_DUPFIXED) ? fp->mp_leaf2_ksize : 0;
-    break;
-  }
-
-  if (unlikely(mx->mx_db.md_xsize != mc->mc_db->md_xsize)) {
-    if (unlikely(mc->mc_db->md_xsize != 0)) {
-      mdbx_error("cursor mismatched nested-db md_xsize %u",
-                 mc->mc_db->md_xsize);
-      return MDBX_CORRUPTED;
-    }
-    if (unlikely((mc->mc_db->md_flags & MDBX_DUPFIXED) == 0)) {
-      mdbx_error("mismatched nested-db md_flags %u", mc->mc_db->md_flags);
-      return MDBX_CORRUPTED;
-    }
-    if (unlikely(mx->mx_db.md_xsize < mc->mc_dbx->md_vlen_min ||
-                 mx->mx_db.md_xsize > mc->mc_dbx->md_vlen_max)) {
-      mdbx_error("mismatched nested-db.md_xsize (%u) <> min/max value-length "
-                 "(%zu/%zu)",
-                 mx->mx_db.md_xsize, mc->mc_dbx->md_vlen_min,
-                 mc->mc_dbx->md_vlen_max);
-      return MDBX_CORRUPTED;
-    }
-    mc->mc_db->md_xsize = mx->mx_db.md_xsize;
-    mc->mc_dbx->md_vlen_min = mc->mc_dbx->md_vlen_max = mx->mx_db.md_xsize;
-  }
-  mx->mx_dbx.md_klen_min = mc->mc_dbx->md_vlen_min;
-  mx->mx_dbx.md_klen_max = mc->mc_dbx->md_vlen_max;
-
-  mdbx_debug("Sub-db -%u root page %" PRIaPGNO, mx->mx_cursor.mc_dbi,
-             mx->mx_db.md_root);
-  mx->mx_dbistate = DBI_VALID | DBI_USRVALID | DBI_DUPDATA;
-  return MDBX_SUCCESS;
-}
-
-/* Fixup a sorted-dups cursor due to underlying update.
- * Sets up some fields that depend on the data from the main cursor.
- * Almost the same as init1, but skips initialization steps if the
- * xcursor had already been used.
- * [in] mc The main cursor whose sorted-dups cursor is to be fixed up.
- * [in] src_mx The xcursor of an up-to-date cursor.
- * [in] new_dupdata True if converting from a non-F_DUPDATA item. */
-static int mdbx_xcursor_init2(MDBX_cursor *mc, MDBX_xcursor *src_mx,
-                              bool new_dupdata) {
-  MDBX_xcursor *mx = mc->mc_xcursor;
-  if (unlikely(mx == nullptr)) {
-    mdbx_error("unexpected dupsort-page for non-dupsort db/cursor (dbi %u)",
-               mc->mc_dbi);
-    return MDBX_CORRUPTED;
-  }
-
-  if (new_dupdata) {
-    mx->mx_cursor.mc_snum = 1;
-    mx->mx_cursor.mc_top = 0;
-    mx->mx_cursor.mc_flags |= C_INITIALIZED;
-    mx->mx_cursor.mc_ki[0] = 0;
-    mx->mx_dbistate = DBI_VALID | DBI_USRVALID | DBI_DUPDATA;
-  }
-
-  mx->mx_dbx.md_klen_min = src_mx->mx_dbx.md_klen_min;
-  mx->mx_dbx.md_klen_max = src_mx->mx_dbx.md_klen_max;
-  mx->mx_dbx.md_cmp = src_mx->mx_dbx.md_cmp;
-  mx->mx_db = src_mx->mx_db;
-  mx->mx_cursor.mc_pg[0] = src_mx->mx_cursor.mc_pg[0];
-  if (mx->mx_cursor.mc_flags & C_INITIALIZED) {
-    mdbx_debug("Sub-db -%u root page %" PRIaPGNO, mx->mx_cursor.mc_dbi,
-               mx->mx_db.md_root);
-  }
-  return MDBX_SUCCESS;
-}
-
-static __inline int mdbx_couple_init(MDBX_cursor_couple *couple,
-                                     const MDBX_dbi dbi, MDBX_txn *const txn,
-                                     MDBX_db *const db, MDBX_dbx *const dbx,
-                                     uint8_t *const dbstate) {
-  couple->outer.mc_signature = MDBX_MC_LIVE;
-  couple->outer.mc_next = NULL;
-  couple->outer.mc_backup = NULL;
-  couple->outer.mc_dbi = dbi;
-  couple->outer.mc_txn = txn;
-  couple->outer.mc_db = db;
-  couple->outer.mc_dbx = dbx;
-  couple->outer.mc_dbistate = dbstate;
-  couple->outer.mc_snum = 0;
-  couple->outer.mc_top = 0;
-  couple->outer.mc_pg[0] = 0;
-  couple->outer.mc_flags = 0;
-  couple->outer.mc_ki[0] = 0;
-  couple->outer.mc_xcursor = NULL;
-
-  int rc = MDBX_SUCCESS;
-  if (unlikely(*couple->outer.mc_dbistate & DBI_STALE)) {
-    rc = mdbx_page_search(&couple->outer, NULL, MDBX_PS_ROOTONLY);
-    rc = (rc != MDBX_NOTFOUND) ? rc : MDBX_SUCCESS;
-  } else if (unlikely(couple->outer.mc_dbx->md_klen_max == 0)) {
-    rc = mdbx_setup_dbx(couple->outer.mc_dbx, couple->outer.mc_db,
-                        txn->mt_env->me_psize);
-  }
-
-  if (couple->outer.mc_db->md_flags & MDBX_DUPSORT) {
-    couple->inner.mx_cursor.mc_signature = MDBX_MC_LIVE;
-    couple->outer.mc_xcursor = &couple->inner;
-    rc = mdbx_xcursor_init0(&couple->outer);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    couple->inner.mx_dbx.md_klen_min = couple->outer.mc_dbx->md_vlen_min;
-    couple->inner.mx_dbx.md_klen_max = couple->outer.mc_dbx->md_vlen_max;
-  }
-  return rc;
-}
-
-/* Initialize a cursor for a given transaction and database. */
-static int mdbx_cursor_init(MDBX_cursor *mc, MDBX_txn *txn, MDBX_dbi dbi) {
-  STATIC_ASSERT(offsetof(MDBX_cursor_couple, outer) == 0);
-  if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
-    return MDBX_BAD_DBI;
-
-  return mdbx_couple_init(container_of(mc, MDBX_cursor_couple, outer), dbi, txn,
-                          &txn->mt_dbs[dbi], &txn->mt_dbxs[dbi],
-                          &txn->mt_dbistate[dbi]);
-}
-
-MDBX_cursor *mdbx_cursor_create(void *context) {
-  MDBX_cursor_couple *couple = mdbx_calloc(1, sizeof(MDBX_cursor_couple));
-  if (unlikely(!couple))
-    return nullptr;
-
-  couple->outer.mc_signature = MDBX_MC_READY4CLOSE;
-  couple->outer.mc_dbi = UINT_MAX;
-  couple->mc_userctx = context;
-  return &couple->outer;
-}
-
-int mdbx_cursor_set_userctx(MDBX_cursor *mc, void *ctx) {
-  if (unlikely(!mc))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_READY4CLOSE &&
-               mc->mc_signature != MDBX_MC_LIVE))
-    return MDBX_EBADSIGN;
-
-  MDBX_cursor_couple *couple = container_of(mc, MDBX_cursor_couple, outer);
-  couple->mc_userctx = ctx;
-  return MDBX_SUCCESS;
-}
-
-void *mdbx_cursor_get_userctx(const MDBX_cursor *mc) {
-  if (unlikely(!mc))
-    return nullptr;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_READY4CLOSE &&
-               mc->mc_signature != MDBX_MC_LIVE))
-    return nullptr;
-
-  MDBX_cursor_couple *couple = container_of(mc, MDBX_cursor_couple, outer);
-  return couple->mc_userctx;
-}
-
-int mdbx_cursor_bind(MDBX_txn *txn, MDBX_cursor *mc, MDBX_dbi dbi) {
-  if (unlikely(!mc))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_READY4CLOSE &&
-               mc->mc_signature != MDBX_MC_LIVE))
-    return MDBX_EBADSIGN;
-
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_VALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(dbi == FREE_DBI && !F_ISSET(txn->mt_flags, MDBX_TXN_RDONLY)))
-    return MDBX_EACCESS;
-
-  if (unlikely(mc->mc_backup)) /* Cursor from parent transaction */ {
-    mdbx_cassert(mc, mc->mc_signature == MDBX_MC_LIVE);
-    if (unlikely(mc->mc_dbi != dbi ||
-                 /* paranoia */ mc->mc_signature != MDBX_MC_LIVE ||
-                 mc->mc_txn != txn))
-      return MDBX_EINVAL;
-
-    assert(mc->mc_db == &txn->mt_dbs[dbi]);
-    assert(mc->mc_dbx == &txn->mt_dbxs[dbi]);
-    assert(mc->mc_dbi == dbi);
-    assert(mc->mc_dbistate == &txn->mt_dbistate[dbi]);
-    return likely(mc->mc_dbi == dbi &&
-                  /* paranoia */ mc->mc_signature == MDBX_MC_LIVE &&
-                  mc->mc_txn == txn)
-               ? MDBX_SUCCESS
-               : MDBX_EINVAL /* Disallow change DBI in nested transactions */;
-  }
-
-  if (mc->mc_signature == MDBX_MC_LIVE) {
-    if (unlikely(!mc->mc_txn || mc->mc_txn->mt_signature != MDBX_MT_SIGNATURE))
-      return MDBX_PROBLEM;
-    if (mc->mc_flags & C_UNTRACK) {
-      mdbx_cassert(mc, !(mc->mc_txn->mt_flags & MDBX_TXN_RDONLY));
-      MDBX_cursor **prev = &mc->mc_txn->tw.cursors[mc->mc_dbi];
-      while (*prev && *prev != mc)
-        prev = &(*prev)->mc_next;
-      mdbx_cassert(mc, *prev == mc);
-      *prev = mc->mc_next;
-    }
-    mc->mc_signature = MDBX_MC_READY4CLOSE;
-    mc->mc_flags = 0;
-    mc->mc_dbi = UINT_MAX;
-    mc->mc_next = NULL;
-    mc->mc_db = NULL;
-    mc->mc_dbx = NULL;
-    mc->mc_dbistate = NULL;
-  }
-  mdbx_cassert(mc, !(mc->mc_flags & C_UNTRACK));
-
-  rc = mdbx_cursor_init(mc, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (!(txn->mt_flags & MDBX_TXN_RDONLY)) {
-    mc->mc_next = txn->tw.cursors[dbi];
-    txn->tw.cursors[dbi] = mc;
-    mc->mc_flags |= C_UNTRACK;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_cursor_open(MDBX_txn *txn, MDBX_dbi dbi, MDBX_cursor **ret) {
-  if (unlikely(!ret))
-    return MDBX_EINVAL;
-  *ret = NULL;
-
-  MDBX_cursor *const mc = mdbx_cursor_create(nullptr);
-  if (unlikely(!mc))
-    return MDBX_ENOMEM;
-
-  int rc = mdbx_cursor_bind(txn, mc, dbi);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    mdbx_cursor_close(mc);
-    return rc;
-  }
-
-  *ret = mc;
-  return MDBX_SUCCESS;
-}
-
-int mdbx_cursor_renew(MDBX_txn *txn, MDBX_cursor *mc) {
-  return likely(mc) ? mdbx_cursor_bind(txn, mc, mc->mc_dbi) : MDBX_EINVAL;
-}
-
-int mdbx_cursor_copy(const MDBX_cursor *src, MDBX_cursor *dest) {
-  if (unlikely(!src))
-    return MDBX_EINVAL;
-  if (unlikely(src->mc_signature != MDBX_MC_LIVE))
-    return (src->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                      : MDBX_EBADSIGN;
-
-  int rc = mdbx_cursor_bind(src->mc_txn, dest, src->mc_dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  assert(dest->mc_db == src->mc_db);
-  assert(dest->mc_dbi == src->mc_dbi);
-  assert(dest->mc_dbx == src->mc_dbx);
-  assert(dest->mc_dbistate == src->mc_dbistate);
-again:
-  assert(dest->mc_txn == src->mc_txn);
-  dest->mc_flags ^= (dest->mc_flags ^ src->mc_flags) & ~C_UNTRACK;
-  dest->mc_top = src->mc_top;
-  dest->mc_snum = src->mc_snum;
-  for (unsigned i = 0; i < src->mc_snum; ++i) {
-    dest->mc_ki[i] = src->mc_ki[i];
-    dest->mc_pg[i] = src->mc_pg[i];
-  }
-
-  if (src->mc_xcursor) {
-    dest->mc_xcursor->mx_db = src->mc_xcursor->mx_db;
-    dest->mc_xcursor->mx_dbx = src->mc_xcursor->mx_dbx;
-    src = &src->mc_xcursor->mx_cursor;
-    dest = &dest->mc_xcursor->mx_cursor;
-    goto again;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-void mdbx_cursor_close(MDBX_cursor *mc) {
-  if (likely(mc)) {
-    mdbx_ensure(NULL, mc->mc_signature == MDBX_MC_LIVE ||
-                          mc->mc_signature == MDBX_MC_READY4CLOSE);
-    MDBX_txn *const txn = mc->mc_txn;
-    if (!mc->mc_backup) {
-      mc->mc_txn = NULL;
-      /* Remove from txn, if tracked.
-       * A read-only txn (!C_UNTRACK) may have been freed already,
-       * so do not peek inside it.  Only write txns track cursors. */
-      if (mc->mc_flags & C_UNTRACK) {
-        mdbx_ensure(txn->mt_env, check_txn_rw(txn, 0) == MDBX_SUCCESS);
-        MDBX_cursor **prev = &txn->tw.cursors[mc->mc_dbi];
-        while (*prev && *prev != mc)
-          prev = &(*prev)->mc_next;
-        mdbx_tassert(txn, *prev == mc);
-        *prev = mc->mc_next;
-      }
-      mc->mc_signature = 0;
-      mc->mc_next = mc;
-      mdbx_free(mc);
-    } else {
-      /* Cursor closed before nested txn ends */
-      mdbx_tassert(txn, mc->mc_signature == MDBX_MC_LIVE);
-      mdbx_ensure(txn->mt_env, check_txn_rw(txn, 0) == MDBX_SUCCESS);
-      mc->mc_signature = MDBX_MC_WAIT4EOT;
-    }
-  }
-}
-
-MDBX_txn *mdbx_cursor_txn(const MDBX_cursor *mc) {
-  if (unlikely(!mc || mc->mc_signature != MDBX_MC_LIVE))
-    return NULL;
-  MDBX_txn *txn = mc->mc_txn;
-  if (unlikely(!txn || txn->mt_signature != MDBX_MT_SIGNATURE))
-    return NULL;
-  if (unlikely(txn->mt_flags & MDBX_TXN_FINISHED))
-    return NULL;
-  return txn;
-}
-
-MDBX_dbi mdbx_cursor_dbi(const MDBX_cursor *mc) {
-  if (unlikely(!mc || mc->mc_signature != MDBX_MC_LIVE))
-    return UINT_MAX;
-  return mc->mc_dbi;
-}
-
-/* Return the count of duplicate data items for the current key */
-int mdbx_cursor_count(const MDBX_cursor *mc, size_t *countp) {
-  if (unlikely(mc == NULL))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  int rc = check_txn(mc->mc_txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(countp == NULL || !(mc->mc_flags & C_INITIALIZED)))
-    return MDBX_EINVAL;
-
-  if (!mc->mc_snum) {
-    *countp = 0;
-    return MDBX_NOTFOUND;
-  }
-
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  if ((mc->mc_flags & C_EOF) && mc->mc_ki[mc->mc_top] >= page_numkeys(mp)) {
-    *countp = 0;
-    return MDBX_NOTFOUND;
-  }
-
-  *countp = 1;
-  if (mc->mc_xcursor != NULL) {
-    MDBX_node *node = page_node(mp, mc->mc_ki[mc->mc_top]);
-    if (F_ISSET(node_flags(node), F_DUPDATA)) {
-      mdbx_cassert(mc, mc->mc_xcursor && (mc->mc_xcursor->mx_cursor.mc_flags &
-                                          C_INITIALIZED));
-      *countp = unlikely(mc->mc_xcursor->mx_db.md_entries > PTRDIFF_MAX)
-                    ? PTRDIFF_MAX
-                    : (size_t)mc->mc_xcursor->mx_db.md_entries;
-    }
-  }
-  return MDBX_SUCCESS;
-}
-
-/* Replace the key for a branch node with a new key.
- * Set MDBX_TXN_ERROR on failure.
- * [in] mc Cursor pointing to the node to operate on.
- * [in] key The new key to use.
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_update_key(MDBX_cursor *mc, const MDBX_val *key) {
-  MDBX_page *mp;
-  MDBX_node *node;
-  char *base;
-  size_t len;
-  int delta, ksize, oksize;
-  int ptr, i, nkeys, indx;
-  DKBUF;
-
-  mdbx_cassert(mc, cursor_is_tracked(mc));
-  indx = mc->mc_ki[mc->mc_top];
-  mp = mc->mc_pg[mc->mc_top];
-  node = page_node(mp, indx);
-  ptr = mp->mp_ptrs[indx];
-  if (MDBX_DEBUG) {
-    MDBX_val k2;
-    char kbuf2[DKBUF_MAXKEYSIZE * 2 + 1];
-    k2.iov_base = node_key(node);
-    k2.iov_len = node_ks(node);
-    mdbx_debug("update key %u (offset %u) [%s] to [%s] on page %" PRIaPGNO,
-               indx, ptr, mdbx_dump_val(&k2, kbuf2, sizeof(kbuf2)), DKEY(key),
-               mp->mp_pgno);
-  }
-
-  /* Sizes must be 2-byte aligned. */
-  ksize = EVEN(key->iov_len);
-  oksize = EVEN(node_ks(node));
-  delta = ksize - oksize;
-
-  /* Shift node contents if EVEN(key length) changed. */
-  if (delta) {
-    if (delta > (int)page_room(mp)) {
-      /* not enough space left, do a delete and split */
-      mdbx_debug("Not enough room, delta = %d, splitting...", delta);
-      pgno_t pgno = node_pgno(node);
-      mdbx_node_del(mc, 0);
-      int rc = mdbx_page_split(mc, key, NULL, pgno, MDBX_SPLIT_REPLACE);
-      if (rc == MDBX_SUCCESS && mdbx_audit_enabled())
-        rc = mdbx_cursor_check(mc, C_UPDATING);
-      return rc;
-    }
-
-    nkeys = page_numkeys(mp);
-    for (i = 0; i < nkeys; i++) {
-      if (mp->mp_ptrs[i] <= ptr) {
-        mdbx_cassert(mc, mp->mp_ptrs[i] >= delta);
-        mp->mp_ptrs[i] -= (indx_t)delta;
-      }
-    }
-
-    base = (char *)mp + mp->mp_upper + PAGEHDRSZ;
-    len = ptr - mp->mp_upper + NODESIZE;
-    memmove(base - delta, base, len);
-    mdbx_cassert(mc, mp->mp_upper >= delta);
-    mp->mp_upper -= (indx_t)delta;
-
-    node = page_node(mp, indx);
-  }
-
-  /* But even if no shift was needed, update ksize */
-  node_set_ks(node, key->iov_len);
-
-  if (likely(key->iov_len /* to avoid UBSAN traps*/ != 0))
-    memcpy(node_key(node), key->iov_base, key->iov_len);
-  return MDBX_SUCCESS;
-}
-
-/* Move a node from csrc to cdst. */
-static int mdbx_node_move(MDBX_cursor *csrc, MDBX_cursor *cdst, int fromleft) {
-  int rc;
-  DKBUF;
-
-  MDBX_page *psrc = csrc->mc_pg[csrc->mc_top];
-  MDBX_page *pdst = cdst->mc_pg[cdst->mc_top];
-  mdbx_cassert(csrc, PAGETYPE(psrc) == PAGETYPE(pdst));
-  mdbx_cassert(csrc, csrc->mc_dbi == cdst->mc_dbi);
-  mdbx_cassert(csrc, csrc->mc_top == cdst->mc_top);
-  if (unlikely(PAGETYPE(psrc) != PAGETYPE(pdst))) {
-  bailout:
-    csrc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-    return MDBX_PROBLEM;
-  }
-
-  MDBX_val key4move;
-  switch (PAGETYPE(psrc)) {
-  case P_BRANCH: {
-    const MDBX_node *srcnode = page_node(psrc, csrc->mc_ki[csrc->mc_top]);
-    mdbx_cassert(csrc, node_flags(srcnode) == 0);
-    const pgno_t srcpg = node_pgno(srcnode);
-    key4move.iov_len = node_ks(srcnode);
-    key4move.iov_base = node_key(srcnode);
-
-    if (csrc->mc_ki[csrc->mc_top] == 0) {
-      const unsigned snum = csrc->mc_snum;
-      mdbx_cassert(csrc, snum > 0);
-      /* must find the lowest key below src */
-      rc = mdbx_page_search_lowest(csrc);
-      MDBX_page *lowest_page = csrc->mc_pg[csrc->mc_top];
-      if (unlikely(rc))
-        return rc;
-      mdbx_cassert(csrc, IS_LEAF(lowest_page));
-      if (unlikely(!IS_LEAF(lowest_page)))
-        goto bailout;
-      if (IS_LEAF2(lowest_page)) {
-        key4move.iov_len = csrc->mc_db->md_xsize;
-        key4move.iov_base = page_leaf2key(lowest_page, 0, key4move.iov_len);
-      } else {
-        const MDBX_node *lowest_node = page_node(lowest_page, 0);
-        key4move.iov_len = node_ks(lowest_node);
-        key4move.iov_base = node_key(lowest_node);
-      }
-
-      /* restore cursor after mdbx_page_search_lowest() */
-      csrc->mc_snum = snum;
-      csrc->mc_top = snum - 1;
-      csrc->mc_ki[csrc->mc_top] = 0;
-
-      /* paranoia */
-      mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
-      mdbx_cassert(csrc, IS_BRANCH(psrc));
-      if (unlikely(!IS_BRANCH(psrc)))
-        goto bailout;
-    }
-
-    if (cdst->mc_ki[cdst->mc_top] == 0) {
-      const unsigned snum = cdst->mc_snum;
-      mdbx_cassert(csrc, snum > 0);
-      MDBX_cursor mn;
-      cursor_copy_internal(cdst, &mn);
-      mn.mc_xcursor = NULL;
-      /* must find the lowest key below dst */
-      rc = mdbx_page_search_lowest(&mn);
-      if (unlikely(rc))
-        return rc;
-      MDBX_page *const lowest_page = mn.mc_pg[mn.mc_top];
-      mdbx_cassert(cdst, IS_LEAF(lowest_page));
-      if (unlikely(!IS_LEAF(lowest_page)))
-        goto bailout;
-      MDBX_val key;
-      if (IS_LEAF2(lowest_page)) {
-        key.iov_len = mn.mc_db->md_xsize;
-        key.iov_base = page_leaf2key(lowest_page, 0, key.iov_len);
-      } else {
-        MDBX_node *lowest_node = page_node(lowest_page, 0);
-        key.iov_len = node_ks(lowest_node);
-        key.iov_base = node_key(lowest_node);
-      }
-
-      /* restore cursor after mdbx_page_search_lowest() */
-      mn.mc_snum = snum;
-      mn.mc_top = snum - 1;
-      mn.mc_ki[mn.mc_top] = 0;
-
-      const intptr_t delta =
-          EVEN(key.iov_len) - EVEN(node_ks(page_node(mn.mc_pg[mn.mc_top], 0)));
-      const intptr_t needed =
-          branch_size(cdst->mc_txn->mt_env, &key4move) + delta;
-      const intptr_t have = page_room(pdst);
-      if (unlikely(needed > have))
-        return MDBX_RESULT_TRUE;
-
-      if (unlikely((rc = mdbx_page_touch(csrc)) ||
-                   (rc = mdbx_page_touch(cdst))))
-        return rc;
-      psrc = csrc->mc_pg[csrc->mc_top];
-      pdst = cdst->mc_pg[cdst->mc_top];
-
-      WITH_CURSOR_TRACKING(mn, rc = mdbx_update_key(&mn, &key));
-      if (unlikely(rc))
-        return rc;
-    } else {
-      const size_t needed = branch_size(cdst->mc_txn->mt_env, &key4move);
-      const size_t have = page_room(pdst);
-      if (unlikely(needed > have))
-        return MDBX_RESULT_TRUE;
-
-      if (unlikely((rc = mdbx_page_touch(csrc)) ||
-                   (rc = mdbx_page_touch(cdst))))
-        return rc;
-      psrc = csrc->mc_pg[csrc->mc_top];
-      pdst = cdst->mc_pg[cdst->mc_top];
-    }
-
-    mdbx_debug("moving %s-node %u [%s] on page %" PRIaPGNO
-               " to node %u on page %" PRIaPGNO,
-               "branch", csrc->mc_ki[csrc->mc_top], DKEY(&key4move),
-               psrc->mp_pgno, cdst->mc_ki[cdst->mc_top], pdst->mp_pgno);
-    /* Add the node to the destination page. */
-    rc =
-        mdbx_node_add_branch(cdst, cdst->mc_ki[cdst->mc_top], &key4move, srcpg);
-  } break;
-
-  case P_LEAF: {
-    /* Mark src and dst as dirty. */
-    if (unlikely((rc = mdbx_page_touch(csrc)) || (rc = mdbx_page_touch(cdst))))
-      return rc;
-    psrc = csrc->mc_pg[csrc->mc_top];
-    pdst = cdst->mc_pg[cdst->mc_top];
-    const MDBX_node *srcnode = page_node(psrc, csrc->mc_ki[csrc->mc_top]);
-    MDBX_val data;
-    data.iov_len = node_ds(srcnode);
-    data.iov_base = node_data(srcnode);
-    key4move.iov_len = node_ks(srcnode);
-    key4move.iov_base = node_key(srcnode);
-    mdbx_debug("moving %s-node %u [%s] on page %" PRIaPGNO
-               " to node %u on page %" PRIaPGNO,
-               "leaf", csrc->mc_ki[csrc->mc_top], DKEY(&key4move),
-               psrc->mp_pgno, cdst->mc_ki[cdst->mc_top], pdst->mp_pgno);
-    /* Add the node to the destination page. */
-    rc = mdbx_node_add_leaf(cdst, cdst->mc_ki[cdst->mc_top], &key4move, &data,
-                            node_flags(srcnode));
-  } break;
-
-  case P_LEAF | P_LEAF2: {
-    /* Mark src and dst as dirty. */
-    if (unlikely((rc = mdbx_page_touch(csrc)) || (rc = mdbx_page_touch(cdst))))
-      return rc;
-    psrc = csrc->mc_pg[csrc->mc_top];
-    pdst = cdst->mc_pg[cdst->mc_top];
-    key4move.iov_len = csrc->mc_db->md_xsize;
-    key4move.iov_base =
-        page_leaf2key(psrc, csrc->mc_ki[csrc->mc_top], key4move.iov_len);
-    mdbx_debug("moving %s-node %u [%s] on page %" PRIaPGNO
-               " to node %u on page %" PRIaPGNO,
-               "leaf2", csrc->mc_ki[csrc->mc_top], DKEY(&key4move),
-               psrc->mp_pgno, cdst->mc_ki[cdst->mc_top], pdst->mp_pgno);
-    /* Add the node to the destination page. */
-    rc = mdbx_node_add_leaf2(cdst, cdst->mc_ki[cdst->mc_top], &key4move);
-  } break;
-
-  default:
-    goto bailout;
-  }
-
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  /* Delete the node from the source page. */
-  mdbx_node_del(csrc, key4move.iov_len);
-
-  mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
-  mdbx_cassert(cdst, pdst == cdst->mc_pg[cdst->mc_top]);
-  mdbx_cassert(csrc, PAGETYPE(psrc) == PAGETYPE(pdst));
-
-  {
-    /* Adjust other cursors pointing to mp */
-    MDBX_cursor *m2, *m3;
-    const MDBX_dbi dbi = csrc->mc_dbi;
-    mdbx_cassert(csrc, csrc->mc_top == cdst->mc_top);
-    if (fromleft) {
-      /* If we're adding on the left, bump others up */
-      for (m2 = csrc->mc_txn->tw.cursors[dbi]; m2; m2 = m2->mc_next) {
-        m3 = (csrc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-        if (!(m3->mc_flags & C_INITIALIZED) || m3->mc_top < csrc->mc_top)
-          continue;
-        if (m3 != cdst && m3->mc_pg[csrc->mc_top] == pdst &&
-            m3->mc_ki[csrc->mc_top] >= cdst->mc_ki[csrc->mc_top]) {
-          m3->mc_ki[csrc->mc_top]++;
-        }
-        if (m3 != csrc && m3->mc_pg[csrc->mc_top] == psrc &&
-            m3->mc_ki[csrc->mc_top] == csrc->mc_ki[csrc->mc_top]) {
-          m3->mc_pg[csrc->mc_top] = pdst;
-          m3->mc_ki[csrc->mc_top] = cdst->mc_ki[cdst->mc_top];
-          mdbx_cassert(csrc, csrc->mc_top > 0);
-          m3->mc_ki[csrc->mc_top - 1]++;
-        }
-        if (XCURSOR_INITED(m3) && IS_LEAF(psrc))
-          XCURSOR_REFRESH(m3, m3->mc_pg[csrc->mc_top], m3->mc_ki[csrc->mc_top]);
-      }
-    } else {
-      /* Adding on the right, bump others down */
-      for (m2 = csrc->mc_txn->tw.cursors[dbi]; m2; m2 = m2->mc_next) {
-        m3 = (csrc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-        if (m3 == csrc)
-          continue;
-        if (!(m3->mc_flags & C_INITIALIZED) || m3->mc_top < csrc->mc_top)
-          continue;
-        if (m3->mc_pg[csrc->mc_top] == psrc) {
-          if (!m3->mc_ki[csrc->mc_top]) {
-            m3->mc_pg[csrc->mc_top] = pdst;
-            m3->mc_ki[csrc->mc_top] = cdst->mc_ki[cdst->mc_top];
-            mdbx_cassert(csrc, csrc->mc_top > 0);
-            m3->mc_ki[csrc->mc_top - 1]--;
-          } else {
-            m3->mc_ki[csrc->mc_top]--;
-          }
-          if (XCURSOR_INITED(m3) && IS_LEAF(psrc))
-            XCURSOR_REFRESH(m3, m3->mc_pg[csrc->mc_top],
-                            m3->mc_ki[csrc->mc_top]);
-        }
-      }
-    }
-  }
-
-  /* Update the parent separators. */
-  if (csrc->mc_ki[csrc->mc_top] == 0) {
-    mdbx_cassert(csrc, csrc->mc_top > 0);
-    if (csrc->mc_ki[csrc->mc_top - 1] != 0) {
-      MDBX_val key;
-      if (IS_LEAF2(psrc)) {
-        key.iov_len = psrc->mp_leaf2_ksize;
-        key.iov_base = page_leaf2key(psrc, 0, key.iov_len);
-      } else {
-        MDBX_node *srcnode = page_node(psrc, 0);
-        key.iov_len = node_ks(srcnode);
-        key.iov_base = node_key(srcnode);
-      }
-      mdbx_debug("update separator for source page %" PRIaPGNO " to [%s]",
-                 psrc->mp_pgno, DKEY(&key));
-      MDBX_cursor mn;
-      cursor_copy_internal(csrc, &mn);
-      mn.mc_xcursor = NULL;
-      mdbx_cassert(csrc, mn.mc_snum > 0);
-      mn.mc_snum--;
-      mn.mc_top--;
-      /* We want mdbx_rebalance to find mn when doing fixups */
-      WITH_CURSOR_TRACKING(mn, rc = mdbx_update_key(&mn, &key));
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-    }
-    if (IS_BRANCH(psrc)) {
-      const MDBX_val nullkey = {0, 0};
-      const indx_t ix = csrc->mc_ki[csrc->mc_top];
-      csrc->mc_ki[csrc->mc_top] = 0;
-      rc = mdbx_update_key(csrc, &nullkey);
-      csrc->mc_ki[csrc->mc_top] = ix;
-      mdbx_cassert(csrc, rc == MDBX_SUCCESS);
-    }
-  }
-
-  if (cdst->mc_ki[cdst->mc_top] == 0) {
-    mdbx_cassert(cdst, cdst->mc_top > 0);
-    if (cdst->mc_ki[cdst->mc_top - 1] != 0) {
-      MDBX_val key;
-      if (IS_LEAF2(pdst)) {
-        key.iov_len = pdst->mp_leaf2_ksize;
-        key.iov_base = page_leaf2key(pdst, 0, key.iov_len);
-      } else {
-        MDBX_node *srcnode = page_node(pdst, 0);
-        key.iov_len = node_ks(srcnode);
-        key.iov_base = node_key(srcnode);
-      }
-      mdbx_debug("update separator for destination page %" PRIaPGNO " to [%s]",
-                 pdst->mp_pgno, DKEY(&key));
-      MDBX_cursor mn;
-      cursor_copy_internal(cdst, &mn);
-      mn.mc_xcursor = NULL;
-      mdbx_cassert(cdst, mn.mc_snum > 0);
-      mn.mc_snum--;
-      mn.mc_top--;
-      /* We want mdbx_rebalance to find mn when doing fixups */
-      WITH_CURSOR_TRACKING(mn, rc = mdbx_update_key(&mn, &key));
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-    }
-    if (IS_BRANCH(pdst)) {
-      const MDBX_val nullkey = {0, 0};
-      const indx_t ix = cdst->mc_ki[cdst->mc_top];
-      cdst->mc_ki[cdst->mc_top] = 0;
-      rc = mdbx_update_key(cdst, &nullkey);
-      cdst->mc_ki[cdst->mc_top] = ix;
-      mdbx_cassert(cdst, rc == MDBX_SUCCESS);
-    }
-  }
-
-  return MDBX_SUCCESS;
-}
-
-/* Merge one page into another.
- *
- * The nodes from the page pointed to by csrc will be copied to the page
- * pointed to by cdst and then the csrc page will be freed.
- *
- * [in] csrc Cursor pointing to the source page.
- * [in] cdst Cursor pointing to the destination page.
- *
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_page_merge(MDBX_cursor *csrc, MDBX_cursor *cdst) {
-  MDBX_val key;
-  int rc;
-
-  mdbx_cassert(csrc, csrc != cdst);
-  mdbx_cassert(csrc, cursor_is_tracked(csrc));
-  mdbx_cassert(cdst, cursor_is_tracked(cdst));
-  const MDBX_page *const psrc = csrc->mc_pg[csrc->mc_top];
-  MDBX_page *pdst = cdst->mc_pg[cdst->mc_top];
-  mdbx_debug("merging page %" PRIaPGNO " into %" PRIaPGNO, psrc->mp_pgno,
-             pdst->mp_pgno);
-
-  mdbx_cassert(csrc, PAGETYPE(psrc) == PAGETYPE(pdst));
-  mdbx_cassert(csrc,
-               csrc->mc_dbi == cdst->mc_dbi && csrc->mc_db == cdst->mc_db);
-  mdbx_cassert(csrc, csrc->mc_snum > 1); /* can't merge root page */
-  mdbx_cassert(cdst, cdst->mc_snum > 1);
-  mdbx_cassert(cdst, cdst->mc_snum < cdst->mc_db->md_depth ||
-                         IS_LEAF(cdst->mc_pg[cdst->mc_db->md_depth - 1]));
-  mdbx_cassert(csrc, csrc->mc_snum < csrc->mc_db->md_depth ||
-                         IS_LEAF(csrc->mc_pg[csrc->mc_db->md_depth - 1]));
-  mdbx_cassert(cdst, page_room(pdst) >= page_used(cdst->mc_txn->mt_env, psrc));
-  const int pagetype = PAGETYPE(psrc);
-
-  /* Move all nodes from src to dst */
-  const unsigned dst_nkeys = page_numkeys(pdst);
-  const unsigned src_nkeys = page_numkeys(psrc);
-  mdbx_cassert(cdst, dst_nkeys + src_nkeys >=
-                         (unsigned)(IS_LEAF(psrc) ? 1 : MDBX_MINKEYS));
-  if (likely(src_nkeys)) {
-    unsigned j = dst_nkeys;
-    if (unlikely(pagetype & P_LEAF2)) {
-      /* Mark dst as dirty. */
-      if (unlikely(rc = mdbx_page_touch(cdst)))
-        return rc;
-
-      key.iov_len = csrc->mc_db->md_xsize;
-      key.iov_base = page_data(psrc);
-      unsigned i = 0;
-      do {
-        rc = mdbx_node_add_leaf2(cdst, j++, &key);
-        if (unlikely(rc != MDBX_SUCCESS))
-          return rc;
-        key.iov_base = (char *)key.iov_base + key.iov_len;
-      } while (++i != src_nkeys);
-    } else {
-      MDBX_node *srcnode = page_node(psrc, 0);
-      key.iov_len = node_ks(srcnode);
-      key.iov_base = node_key(srcnode);
-      if (pagetype & P_BRANCH) {
-        MDBX_cursor mn;
-        cursor_copy_internal(csrc, &mn);
-        mn.mc_xcursor = NULL;
-        /* must find the lowest key below src */
-        rc = mdbx_page_search_lowest(&mn);
-        if (unlikely(rc))
-          return rc;
-
-        const MDBX_page *mp = mn.mc_pg[mn.mc_top];
-        if (likely(!IS_LEAF2(mp))) {
-          mdbx_cassert(&mn, IS_LEAF(mp));
-          const MDBX_node *lowest = page_node(mp, 0);
-          key.iov_len = node_ks(lowest);
-          key.iov_base = node_key(lowest);
-        } else {
-          mdbx_cassert(&mn, mn.mc_top > csrc->mc_top);
-          key.iov_len = mp->mp_leaf2_ksize;
-          key.iov_base = page_leaf2key(mp, mn.mc_ki[mn.mc_top], key.iov_len);
-        }
-        mdbx_cassert(&mn, key.iov_len >= csrc->mc_dbx->md_klen_min);
-        mdbx_cassert(&mn, key.iov_len <= csrc->mc_dbx->md_klen_max);
-
-        const size_t dst_room = page_room(pdst);
-        const size_t src_used = page_used(cdst->mc_txn->mt_env, psrc);
-        const size_t space_needed = src_used - node_ks(srcnode) + key.iov_len;
-        if (unlikely(space_needed > dst_room))
-          return MDBX_RESULT_TRUE;
-      }
-
-      /* Mark dst as dirty. */
-      if (unlikely(rc = mdbx_page_touch(cdst)))
-        return rc;
-
-      unsigned i = 0;
-      while (true) {
-        if (pagetype & P_LEAF) {
-          MDBX_val data;
-          data.iov_len = node_ds(srcnode);
-          data.iov_base = node_data(srcnode);
-          rc = mdbx_node_add_leaf(cdst, j++, &key, &data, node_flags(srcnode));
-        } else {
-          mdbx_cassert(csrc, node_flags(srcnode) == 0);
-          rc = mdbx_node_add_branch(cdst, j++, &key, node_pgno(srcnode));
-        }
-        if (unlikely(rc != MDBX_SUCCESS))
-          return rc;
-
-        if (++i == src_nkeys)
-          break;
-        srcnode = page_node(psrc, i);
-        key.iov_len = node_ks(srcnode);
-        key.iov_base = node_key(srcnode);
-      }
-    }
-
-    pdst = cdst->mc_pg[cdst->mc_top];
-    mdbx_debug("dst page %" PRIaPGNO " now has %u keys (%.1f%% filled)",
-               pdst->mp_pgno, page_numkeys(pdst),
-               page_fill(cdst->mc_txn->mt_env, pdst));
-
-    mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
-    mdbx_cassert(cdst, pdst == cdst->mc_pg[cdst->mc_top]);
-  }
-
-  /* Unlink the src page from parent and add to free list. */
-  csrc->mc_top--;
-  mdbx_node_del(csrc, 0);
-  if (csrc->mc_ki[csrc->mc_top] == 0) {
-    const MDBX_val nullkey = {0, 0};
-    rc = mdbx_update_key(csrc, &nullkey);
-    if (unlikely(rc)) {
-      csrc->mc_top++;
-      return rc;
-    }
-  }
-  csrc->mc_top++;
-
-  mdbx_cassert(csrc, psrc == csrc->mc_pg[csrc->mc_top]);
-  mdbx_cassert(cdst, pdst == cdst->mc_pg[cdst->mc_top]);
-
-  {
-    /* Adjust other cursors pointing to mp */
-    MDBX_cursor *m2, *m3;
-    const MDBX_dbi dbi = csrc->mc_dbi;
-    const unsigned top = csrc->mc_top;
-
-    for (m2 = csrc->mc_txn->tw.cursors[dbi]; m2; m2 = m2->mc_next) {
-      m3 = (csrc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-      if (m3 == csrc || top >= m3->mc_snum)
-        continue;
-      if (m3->mc_pg[top] == psrc) {
-        m3->mc_pg[top] = pdst;
-        mdbx_cassert(m3, dst_nkeys + m3->mc_ki[top] <= UINT16_MAX);
-        m3->mc_ki[top] += (indx_t)dst_nkeys;
-        m3->mc_ki[top - 1] = cdst->mc_ki[top - 1];
-      } else if (m3->mc_pg[top - 1] == csrc->mc_pg[top - 1] &&
-                 m3->mc_ki[top - 1] > csrc->mc_ki[top - 1]) {
-        m3->mc_ki[top - 1]--;
-      }
-      if (XCURSOR_INITED(m3) && IS_LEAF(psrc))
-        XCURSOR_REFRESH(m3, m3->mc_pg[top], m3->mc_ki[top]);
-    }
-  }
-
-  /* If not operating on GC, allow this page to be reused
-   * in this txn. Otherwise just add to free list. */
-  rc = mdbx_page_retire(csrc, (MDBX_page *)psrc);
-  if (unlikely(rc))
-    return rc;
-
-  mdbx_cassert(cdst, cdst->mc_db->md_entries > 0);
-  mdbx_cassert(cdst, cdst->mc_snum <= cdst->mc_db->md_depth);
-  mdbx_cassert(cdst, cdst->mc_top > 0);
-  mdbx_cassert(cdst, cdst->mc_snum == cdst->mc_top + 1);
-  MDBX_page *const top_page = cdst->mc_pg[cdst->mc_top];
-  const indx_t top_indx = cdst->mc_ki[cdst->mc_top];
-  const unsigned save_snum = cdst->mc_snum;
-  const uint16_t save_depth = cdst->mc_db->md_depth;
-  mdbx_cursor_pop(cdst);
-  rc = mdbx_rebalance(cdst);
-  if (unlikely(rc))
-    return rc;
-
-  mdbx_cassert(cdst, cdst->mc_db->md_entries > 0);
-  mdbx_cassert(cdst, cdst->mc_snum <= cdst->mc_db->md_depth);
-  mdbx_cassert(cdst, cdst->mc_snum == cdst->mc_top + 1);
-
-  if (IS_LEAF(cdst->mc_pg[cdst->mc_top])) {
-    /* LY: don't touch cursor if top-page is a LEAF */
-    mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
-                           PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
-    return MDBX_SUCCESS;
-  }
-
-  mdbx_cassert(cdst, page_numkeys(top_page) == dst_nkeys + src_nkeys);
-
-  if (pagetype != PAGETYPE(top_page)) {
-    /* LY: LEAF-page becomes BRANCH, unable restore cursor's stack */
-    goto bailout;
-  }
-
-  if (top_page == cdst->mc_pg[cdst->mc_top]) {
-    /* LY: don't touch cursor if prev top-page already on the top */
-    mdbx_cassert(cdst, cdst->mc_ki[cdst->mc_top] == top_indx);
-    mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
-                           PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
-    return MDBX_SUCCESS;
-  }
-
-  const int new_snum = save_snum - save_depth + cdst->mc_db->md_depth;
-  if (unlikely(new_snum < 1 || new_snum > cdst->mc_db->md_depth)) {
-    /* LY: out of range, unable restore cursor's stack */
-    goto bailout;
-  }
-
-  if (top_page == cdst->mc_pg[new_snum - 1]) {
-    mdbx_cassert(cdst, cdst->mc_ki[new_snum - 1] == top_indx);
-    /* LY: restore cursor stack */
-    cdst->mc_snum = (uint16_t)new_snum;
-    cdst->mc_top = (uint16_t)new_snum - 1;
-    mdbx_cassert(cdst, cdst->mc_snum < cdst->mc_db->md_depth ||
-                           IS_LEAF(cdst->mc_pg[cdst->mc_db->md_depth - 1]));
-    mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
-                           PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
-    return MDBX_SUCCESS;
-  }
-
-  MDBX_page *const stub_page = (MDBX_page *)(~(uintptr_t)top_page);
-  const indx_t stub_indx = top_indx;
-  if (save_depth > cdst->mc_db->md_depth &&
-      ((cdst->mc_pg[save_snum - 1] == top_page &&
-        cdst->mc_ki[save_snum - 1] == top_indx) ||
-       (cdst->mc_pg[save_snum - 1] == stub_page &&
-        cdst->mc_ki[save_snum - 1] == stub_indx))) {
-    /* LY: restore cursor stack */
-    cdst->mc_pg[new_snum - 1] = top_page;
-    cdst->mc_ki[new_snum - 1] = top_indx;
-    cdst->mc_pg[new_snum] = (MDBX_page *)(~(uintptr_t)cdst->mc_pg[new_snum]);
-    cdst->mc_ki[new_snum] = ~cdst->mc_ki[new_snum];
-    cdst->mc_snum = (uint16_t)new_snum;
-    cdst->mc_top = (uint16_t)new_snum - 1;
-    mdbx_cassert(cdst, cdst->mc_snum < cdst->mc_db->md_depth ||
-                           IS_LEAF(cdst->mc_pg[cdst->mc_db->md_depth - 1]));
-    mdbx_cassert(cdst, IS_LEAF(cdst->mc_pg[cdst->mc_top]) ||
-                           PAGETYPE(cdst->mc_pg[cdst->mc_top]) == pagetype);
-    return MDBX_SUCCESS;
-  }
-
-bailout:
-  /* LY: unable restore cursor's stack */
-  cdst->mc_flags &= ~C_INITIALIZED;
-  return MDBX_CURSOR_FULL;
-}
-
-/* Copy the contents of a cursor.
- * [in] csrc The cursor to copy from.
- * [out] cdst The cursor to copy to. */
-static void cursor_copy_internal(const MDBX_cursor *csrc, MDBX_cursor *cdst) {
-  mdbx_cassert(csrc,
-               csrc->mc_txn->mt_txnid >= csrc->mc_txn->mt_env->me_oldest->weak);
-  cdst->mc_txn = csrc->mc_txn;
-  cdst->mc_dbi = csrc->mc_dbi;
-  cdst->mc_db = csrc->mc_db;
-  cdst->mc_dbx = csrc->mc_dbx;
-  cdst->mc_snum = csrc->mc_snum;
-  cdst->mc_top = csrc->mc_top;
-  cdst->mc_flags = csrc->mc_flags;
-  cdst->mc_dbistate = csrc->mc_dbistate;
-
-  for (unsigned i = 0; i < csrc->mc_snum; i++) {
-    cdst->mc_pg[i] = csrc->mc_pg[i];
-    cdst->mc_ki[i] = csrc->mc_ki[i];
-  }
-}
-
-/* Rebalance the tree after a delete operation.
- * [in] mc Cursor pointing to the page where rebalancing should begin.
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_rebalance(MDBX_cursor *mc) {
-  mdbx_cassert(mc, cursor_is_tracked(mc));
-  mdbx_cassert(mc, mc->mc_snum > 0);
-  mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
-                       IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
-  const int pagetype = PAGETYPE(mc->mc_pg[mc->mc_top]);
-
-  STATIC_ASSERT(P_BRANCH == 1);
-  const unsigned minkeys = (pagetype & P_BRANCH) + 1;
-
-  /* The threshold of minimum page fill factor, in form of a negative binary
-   * exponent, i.e. X = 2 means 1/(2**X) == 1/(2**2) == 1/4 == 25%.
-   * Pages emptier than this are candidates for merging. */
-  const unsigned threshold_fill_exp2 = 2;
-
-  /* The threshold of minimum page fill factor, as a number of free bytes on a
-   * page. Pages emptier than this are candidates for merging. */
-  const unsigned room_threshold =
-      page_space(mc->mc_txn->mt_env) -
-      (page_space(mc->mc_txn->mt_env) >> threshold_fill_exp2);
-
-  const MDBX_page *const tp = mc->mc_pg[mc->mc_top];
-  mdbx_debug("rebalancing %s page %" PRIaPGNO " (has %u keys, %.1f%% full)",
-             (pagetype & P_LEAF) ? "leaf" : "branch", tp->mp_pgno,
-             page_numkeys(tp), page_fill(mc->mc_txn->mt_env, tp));
-
-  if (unlikely(page_numkeys(tp) < minkeys)) {
-    mdbx_debug("page %" PRIaPGNO " must be merged due keys < %u threshold",
-               tp->mp_pgno, minkeys);
-  } else if (unlikely(page_room(tp) > room_threshold)) {
-    mdbx_debug("page %" PRIaPGNO " should be merged due room %u > %u threshold",
-               tp->mp_pgno, page_room(tp), room_threshold);
-  } else {
-    mdbx_debug("no need to rebalance page %" PRIaPGNO
-               ", room %u < %u threshold",
-               tp->mp_pgno, page_room(tp), room_threshold);
-    mdbx_cassert(mc, mc->mc_db->md_entries > 0);
-    return MDBX_SUCCESS;
-  }
-
-  int rc;
-  if (mc->mc_snum < 2) {
-    MDBX_page *const mp = mc->mc_pg[0];
-    const unsigned nkeys = page_numkeys(mp);
-    mdbx_cassert(mc, (mc->mc_db->md_entries == 0) == (nkeys == 0));
-    if (IS_SUBP(mp)) {
-      mdbx_debug("%s", "Can't rebalance a subpage, ignoring");
-      mdbx_cassert(mc, pagetype & P_LEAF);
-      return MDBX_SUCCESS;
-    }
-    if (nkeys == 0) {
-      mdbx_cassert(mc, IS_LEAF(mp));
-      mdbx_debug("%s", "tree is completely empty");
-      mc->mc_db->md_root = P_INVALID;
-      mc->mc_db->md_depth = 0;
-      mdbx_cassert(mc, mc->mc_db->md_branch_pages == 0 &&
-                           mc->mc_db->md_overflow_pages == 0 &&
-                           mc->mc_db->md_leaf_pages == 1);
-      /* Adjust cursors pointing to mp */
-      for (MDBX_cursor *m2 = mc->mc_txn->tw.cursors[mc->mc_dbi]; m2;
-           m2 = m2->mc_next) {
-        MDBX_cursor *m3 =
-            (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-        if (m3 == mc || !(m3->mc_flags & C_INITIALIZED))
-          continue;
-        if (m3->mc_pg[0] == mp) {
-          m3->mc_snum = 0;
-          m3->mc_top = 0;
-          m3->mc_flags &= ~C_INITIALIZED;
-        }
-      }
-      mc->mc_snum = 0;
-      mc->mc_top = 0;
-      mc->mc_flags &= ~C_INITIALIZED;
-
-      rc = mdbx_page_retire(mc, mp);
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-    } else if (IS_BRANCH(mp) && nkeys == 1) {
-      mdbx_debug("%s", "collapsing root page!");
-      mc->mc_db->md_root = node_pgno(page_node(mp, 0));
-      rc = mdbx_page_get(mc, mc->mc_db->md_root, &mc->mc_pg[0], NULL,
-                         pp_txnid4chk(mp, mc->mc_txn));
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-      mc->mc_db->md_depth--;
-      mc->mc_ki[0] = mc->mc_ki[1];
-      for (int i = 1; i < mc->mc_db->md_depth; i++) {
-        mc->mc_pg[i] = mc->mc_pg[i + 1];
-        mc->mc_ki[i] = mc->mc_ki[i + 1];
-      }
-
-      /* Adjust other cursors pointing to mp */
-      for (MDBX_cursor *m2 = mc->mc_txn->tw.cursors[mc->mc_dbi]; m2;
-           m2 = m2->mc_next) {
-        MDBX_cursor *m3 =
-            (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-        if (m3 == mc || !(m3->mc_flags & C_INITIALIZED))
-          continue;
-        if (m3->mc_pg[0] == mp) {
-          for (int i = 0; i < mc->mc_db->md_depth; i++) {
-            m3->mc_pg[i] = m3->mc_pg[i + 1];
-            m3->mc_ki[i] = m3->mc_ki[i + 1];
-          }
-          m3->mc_snum--;
-          m3->mc_top--;
-        }
-      }
-      mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]) ||
-                           PAGETYPE(mc->mc_pg[mc->mc_top]) == pagetype);
-      mdbx_cassert(mc, mc->mc_snum < mc->mc_db->md_depth ||
-                           IS_LEAF(mc->mc_pg[mc->mc_db->md_depth - 1]));
-
-      rc = mdbx_page_retire(mc, mp);
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-    } else {
-      mdbx_debug("root page %" PRIaPGNO
-                 " doesn't need rebalancing (flags 0x%x)",
-                 mp->mp_pgno, mp->mp_flags);
-    }
-    return MDBX_SUCCESS;
-  }
-
-  /* The parent (branch page) must have at least 2 pointers,
-   * otherwise the tree is invalid. */
-  const unsigned pre_top = mc->mc_top - 1;
-  mdbx_cassert(mc, IS_BRANCH(mc->mc_pg[pre_top]));
-  mdbx_cassert(mc, !IS_SUBP(mc->mc_pg[0]));
-  mdbx_cassert(mc, page_numkeys(mc->mc_pg[pre_top]) > 1);
-
-  /* Leaf page fill factor is below the threshold.
-   * Try to move keys from left or right neighbor, or
-   * merge with a neighbor page. */
-
-  /* Find neighbors. */
-  MDBX_cursor mn;
-  cursor_copy_internal(mc, &mn);
-  mn.mc_xcursor = NULL;
-
-  MDBX_page *left = nullptr, *right = nullptr;
-  if (mn.mc_ki[pre_top] > 0) {
-    rc = mdbx_page_get(
-        &mn, node_pgno(page_node(mn.mc_pg[pre_top], mn.mc_ki[pre_top] - 1)),
-        &left, NULL, pp_txnid4chk(mn.mc_pg[pre_top], mc->mc_txn));
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    mdbx_cassert(mc, PAGETYPE(left) == PAGETYPE(mc->mc_pg[mc->mc_top]));
-  }
-  if (mn.mc_ki[pre_top] + 1u < page_numkeys(mn.mc_pg[pre_top])) {
-    rc = mdbx_page_get(
-        &mn, node_pgno(page_node(mn.mc_pg[pre_top], mn.mc_ki[pre_top] + 1)),
-        &right, NULL, pp_txnid4chk(mn.mc_pg[pre_top], mc->mc_txn));
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    mdbx_cassert(mc, PAGETYPE(right) == PAGETYPE(mc->mc_pg[mc->mc_top]));
-  }
-
-  const indx_t ki_top = mc->mc_ki[mc->mc_top];
-  const indx_t ki_pre_top = mn.mc_ki[pre_top];
-  const indx_t nkeys = (indx_t)page_numkeys(mn.mc_pg[mn.mc_top]);
-  if (left && page_room(left) > room_threshold &&
-      (!right || page_room(right) < page_room(left))) {
-    /* try merge with left */
-    mdbx_cassert(mc, page_numkeys(left) >= minkeys);
-    mn.mc_pg[mn.mc_top] = left;
-    mn.mc_ki[mn.mc_top - 1] = ki_pre_top - 1;
-    mn.mc_ki[mn.mc_top] = (indx_t)(page_numkeys(left) - 1);
-    mc->mc_ki[mc->mc_top] = 0;
-    const indx_t new_ki = (indx_t)(ki_top + page_numkeys(left));
-    mn.mc_ki[mn.mc_top] += mc->mc_ki[mn.mc_top] + 1;
-    /* We want mdbx_rebalance to find mn when doing fixups */
-    WITH_CURSOR_TRACKING(mn, rc = mdbx_page_merge(mc, &mn));
-    if (likely(rc != MDBX_RESULT_TRUE)) {
-      cursor_copy_internal(&mn, mc);
-      mc->mc_ki[mc->mc_top] = new_ki;
-      mdbx_cassert(mc, rc || page_numkeys(mc->mc_pg[mc->mc_top]) >= minkeys);
-      return rc;
-    }
-  }
-  if (right && page_room(right) > room_threshold) {
-    /* try merge with right */
-    mdbx_cassert(mc, page_numkeys(right) >= minkeys);
-    mn.mc_pg[mn.mc_top] = right;
-    mn.mc_ki[mn.mc_top - 1] = ki_pre_top + 1;
-    mn.mc_ki[mn.mc_top] = 0;
-    mc->mc_ki[mc->mc_top] = nkeys;
-    WITH_CURSOR_TRACKING(mn, rc = mdbx_page_merge(&mn, mc));
-    if (likely(rc != MDBX_RESULT_TRUE)) {
-      mc->mc_ki[mc->mc_top] = ki_top;
-      mdbx_cassert(mc, rc || page_numkeys(mc->mc_pg[mc->mc_top]) >= minkeys);
-      return rc;
-    }
-  }
-  if (left && page_numkeys(left) > minkeys &&
-      (!right || page_numkeys(right) <= minkeys ||
-       page_room(right) > page_room(left))) {
-    /* try move from left */
-    mn.mc_pg[mn.mc_top] = left;
-    mn.mc_ki[mn.mc_top - 1] = ki_pre_top - 1;
-    mn.mc_ki[mn.mc_top] = (indx_t)(page_numkeys(left) - 1);
-    mc->mc_ki[mc->mc_top] = 0;
-    WITH_CURSOR_TRACKING(mn, rc = mdbx_node_move(&mn, mc, true));
-    if (likely(rc != MDBX_RESULT_TRUE)) {
-      mc->mc_ki[mc->mc_top] = ki_top + 1;
-      mdbx_cassert(mc, rc || page_numkeys(mc->mc_pg[mc->mc_top]) >= minkeys);
-      return rc;
-    }
-  }
-  if (right && page_numkeys(right) > minkeys) {
-    /* try move from right */
-    mn.mc_pg[mn.mc_top] = right;
-    mn.mc_ki[mn.mc_top - 1] = ki_pre_top + 1;
-    mn.mc_ki[mn.mc_top] = 0;
-    mc->mc_ki[mc->mc_top] = nkeys;
-    WITH_CURSOR_TRACKING(mn, rc = mdbx_node_move(&mn, mc, false));
-    if (likely(rc != MDBX_RESULT_TRUE)) {
-      mc->mc_ki[mc->mc_top] = ki_top;
-      mdbx_cassert(mc, rc || page_numkeys(mc->mc_pg[mc->mc_top]) >= minkeys);
-      return rc;
-    }
-  }
-
-  if (nkeys >= minkeys) {
-#if MDBX_DEBUG > 0
-    if (mdbx_audit_enabled())
-      return mdbx_cursor_check(mc, C_UPDATING);
-#endif
-    return MDBX_SUCCESS;
-  }
-
-  if (left && (!right || page_room(left) > page_room(right))) {
-    /* try merge with left */
-    mdbx_cassert(mc, page_numkeys(left) >= minkeys);
-    mn.mc_pg[mn.mc_top] = left;
-    mn.mc_ki[mn.mc_top - 1] = ki_pre_top - 1;
-    mn.mc_ki[mn.mc_top] = (indx_t)(page_numkeys(left) - 1);
-    mc->mc_ki[mc->mc_top] = 0;
-    const indx_t new_ki = (indx_t)(ki_top + page_numkeys(left));
-    mn.mc_ki[mn.mc_top] += mc->mc_ki[mn.mc_top] + 1;
-    /* We want mdbx_rebalance to find mn when doing fixups */
-    WITH_CURSOR_TRACKING(mn, rc = mdbx_page_merge(mc, &mn));
-    if (likely(rc != MDBX_RESULT_TRUE)) {
-      cursor_copy_internal(&mn, mc);
-      mc->mc_ki[mc->mc_top] = new_ki;
-      mdbx_cassert(mc, rc || page_numkeys(mc->mc_pg[mc->mc_top]) >= minkeys);
-      return rc;
-    }
-  }
-  if (likely(right)) {
-    /* try merge with right */
-    mdbx_cassert(mc, page_numkeys(right) >= minkeys);
-    mn.mc_pg[mn.mc_top] = right;
-    mn.mc_ki[mn.mc_top - 1] = ki_pre_top + 1;
-    mn.mc_ki[mn.mc_top] = 0;
-    mc->mc_ki[mc->mc_top] = nkeys;
-    WITH_CURSOR_TRACKING(mn, rc = mdbx_page_merge(&mn, mc));
-    if (likely(rc != MDBX_RESULT_TRUE)) {
-      mc->mc_ki[mc->mc_top] = ki_top;
-      mdbx_cassert(mc, rc || page_numkeys(mc->mc_pg[mc->mc_top]) >= minkeys);
-      return rc;
-    }
-  }
-  return MDBX_PROBLEM;
-}
-
-static __cold int mdbx_page_check(MDBX_cursor *const mc,
-                                  const MDBX_page *const mp, unsigned options) {
-  options |= mc->mc_flags & (C_COPYING | C_UPDATING | C_RETIRING | C_SKIPORD);
-  MDBX_env *const env = mc->mc_txn->mt_env;
-  const unsigned nkeys = page_numkeys(mp);
-  char *const end_of_page = (char *)mp + env->me_psize;
-  if (unlikely(mp->mp_pgno < MIN_PAGENO || mp->mp_pgno > MAX_PAGENO))
-    return bad_page(mp, "invalid pgno (%u)\n", mp->mp_pgno);
-  if (IS_OVERFLOW(mp)) {
-    if (unlikely(mp->mp_pages < 1 && mp->mp_pages >= MAX_PAGENO / 2))
-      return bad_page(mp, "invalid overflow n-pages (%u)\n", mp->mp_pages);
-    if (unlikely(mp->mp_pgno + mp->mp_pages > mc->mc_txn->mt_next_pgno))
-      return bad_page(mp, "overflow page beyond (%u) next-pgno\n",
-                      mp->mp_pgno + mp->mp_pages);
-    return MDBX_SUCCESS;
-  }
-
-  int rc = MDBX_SUCCESS;
-  if ((options & C_UPDATING) == 0 || !IS_DIRTY(mp)) {
-    if (unlikely(nkeys < 2 && IS_BRANCH(mp)))
-      rc = bad_page(mp, "branch-page nkey (%u) < 2\n", nkeys);
-  }
-
-  MDBX_val here, prev = {0, 0};
-  for (unsigned i = 0; i < nkeys; ++i) {
-    if (IS_LEAF2(mp)) {
-      const size_t ksize = mp->mp_leaf2_ksize;
-      char *const key = page_leaf2key(mp, i, ksize);
-      if (unlikely(end_of_page < key + ksize)) {
-        rc = bad_page(mp, "leaf2-key beyond (%zu) page-end\n",
-                      key + ksize - end_of_page);
-        continue;
-      }
-
-      if ((options & C_COPYING) == 0) {
-        if (unlikely(ksize != mc->mc_dbx->md_klen_min)) {
-          if (unlikely(ksize < mc->mc_dbx->md_klen_min ||
-                       ksize > mc->mc_dbx->md_klen_max))
-            rc = bad_page(
-                mp, "leaf2-key size (%zu) <> min/max key-length (%zu/%zu)\n",
-                ksize, mc->mc_dbx->md_klen_min, mc->mc_dbx->md_klen_max);
-          else
-            mc->mc_dbx->md_klen_min = mc->mc_dbx->md_klen_max = ksize;
-        }
-        if ((options & C_SKIPORD) == 0) {
-          here.iov_len = ksize;
-          here.iov_base = key;
-          if (prev.iov_base && unlikely(mc->mc_dbx->md_cmp(&here, &prev) <= 0))
-            rc = bad_page(mp, "leaf2-key #%u wrong order\n", i);
-          prev = here;
-        }
-      }
-    } else {
-      const MDBX_node *const node = page_node(mp, i);
-      const char *node_end = (char *)node + NODESIZE;
-      if (unlikely(node_end > end_of_page)) {
-        rc = bad_page(mp, "node (%zu) beyond page-end\n",
-                      node_end - end_of_page);
-        continue;
-      }
-      if (IS_LEAF(mp) || i > 0) {
-        size_t ksize = node_ks(node);
-        char *key = node_key(node);
-        if (unlikely(end_of_page < key + ksize)) {
-          rc = bad_page(mp, "node-key (%zu) beyond page-end\n",
-                        key + ksize - end_of_page);
-          continue;
-        }
-
-        if ((options & C_COPYING) == 0) {
-          if (unlikely(ksize < mc->mc_dbx->md_klen_min ||
-                       ksize > mc->mc_dbx->md_klen_max))
-            rc = bad_page(
-                mp, "node-key size (%zu) <> min/max key-length (%zu/%zu)\n",
-                ksize, mc->mc_dbx->md_klen_min, mc->mc_dbx->md_klen_max);
-
-          if ((options & C_SKIPORD) == 0) {
-            here.iov_base = key;
-            here.iov_len = ksize;
-            if (prev.iov_base &&
-                unlikely(mc->mc_dbx->md_cmp(&here, &prev) <= 0))
-              rc = bad_page(mp, "node-key #%u wrong order\n", i);
-            prev = here;
-          }
-        }
-      }
-      if (IS_BRANCH(mp)) {
-        if ((options & C_RETIRING) == 0) {
-          const pgno_t ref = node_pgno(node);
-          if (unlikely(ref < MIN_PAGENO || ref >= mc->mc_txn->mt_next_pgno))
-            rc = bad_page(mp, "branch-node wrong pgno (%u)\n", ref);
-        }
-        continue;
-      }
-
-      switch (node_flags(node)) {
-      default:
-        rc = bad_page(mp, "invalid node flags (%u)\n", node_flags(node));
-        break;
-      case F_BIGDATA /* data on large-page */:
-      case 0 /* usual */:
-      case F_SUBDATA /* sub-db */:
-      case F_SUBDATA | F_DUPDATA /* dupsorted sub-tree */:
-      case F_DUPDATA /* short sub-page */:
-        break;
-      }
-
-      if (node_flags(node) & F_BIGDATA) {
-        const size_t dsize = node_ds(node);
-        if ((options & C_COPYING) == 0) {
-          if (unlikely(dsize <= mc->mc_dbx->md_vlen_min ||
-                       dsize > mc->mc_dbx->md_vlen_max))
-            rc = bad_page(
-                mp,
-                "big-node data size (%zu) <> min/max value-length (%zu/%zu)\n",
-                dsize, mc->mc_dbx->md_vlen_min, mc->mc_dbx->md_vlen_max);
-        }
-        if ((options & C_RETIRING) == 0) {
-          MDBX_page *lp;
-          int err = mdbx_page_get(mc, node_largedata_pgno(node), &lp, NULL,
-                                  pp_txnid4chk(mp, mc->mc_txn));
-          if (unlikely(err != MDBX_SUCCESS))
-            return err;
-          if (unlikely(!IS_OVERFLOW(lp))) {
-            rc = bad_page(mp, "big-node refs to non-overflow page (%u)\n",
-                          lp->mp_pgno);
-            continue;
-          }
-          if (unlikely(number_of_ovpages(env, dsize) > lp->mp_pages))
-            rc =
-                bad_page(mp, "big-node size (%zu) mismatch n-pages size (%u)\n",
-                         dsize, lp->mp_pages);
-        }
-        continue;
-      }
-
-      const size_t dsize = node_ds(node);
-      const char *const data = node_data(node);
-      if (unlikely(end_of_page < data + dsize)) {
-        rc = bad_page(mp,
-                      "node-data(%u of %u, %zu bytes) beyond (%zu) page-end\n",
-                      i, nkeys, dsize, data + dsize - end_of_page);
-        continue;
-      }
-
-      switch (node_flags(node)) {
-      default:
-        /* wrong, but already handled */
-        continue;
-      case 0 /* usual */:
-        if ((options & C_COPYING) == 0) {
-          if (unlikely(dsize < mc->mc_dbx->md_vlen_min ||
-                       dsize > mc->mc_dbx->md_vlen_max)) {
-            rc = bad_page(
-                mp, "node-data size (%zu) <> min/max value-length (%zu/%zu)\n",
-                dsize, mc->mc_dbx->md_vlen_min, mc->mc_dbx->md_vlen_max);
-            continue;
-          }
-        }
-        break;
-      case F_SUBDATA /* sub-db */:
-        if (unlikely(dsize != sizeof(MDBX_db))) {
-          rc = bad_page(mp, "invalid sub-db record size (%zu)\n", dsize);
-          continue;
-        }
-        break;
-      case F_SUBDATA | F_DUPDATA /* dupsorted sub-tree */:
-        if (unlikely(dsize != sizeof(MDBX_db))) {
-          rc = bad_page(mp, "invalid nested-db record size (%zu)\n", dsize);
-          continue;
-        }
-        break;
-      case F_DUPDATA /* short sub-page */:
-        if (unlikely(dsize <= PAGEHDRSZ)) {
-          rc = bad_page(mp, "invalid nested-page record size (%zu)\n", dsize);
-          continue;
-        } else {
-          const MDBX_page *const sp = (MDBX_page *)data;
-          const char *const end_of_subpage = data + dsize;
-          const int nsubkeys = page_numkeys(sp);
-          switch (sp->mp_flags & ~P_DIRTY /* ignore for sub-pages */) {
-          case P_LEAF | P_SUBP:
-          case P_LEAF | P_LEAF2 | P_SUBP:
-            break;
-          default:
-            rc = bad_page(mp, "invalid nested-page flags (%u)\n", sp->mp_flags);
-            continue;
-          }
-
-          MDBX_val sub_here, sub_prev = {0, 0};
-          for (int j = 0; j < nsubkeys; j++) {
-            if (IS_LEAF2(sp)) {
-              /* LEAF2 pages have no mp_ptrs[] or node headers */
-              size_t sub_ksize = sp->mp_leaf2_ksize;
-              char *sub_key = page_leaf2key(sp, j, sub_ksize);
-              if (unlikely(end_of_subpage < sub_key + sub_ksize)) {
-                rc = bad_page(mp, "nested-leaf2-key beyond (%zu) nested-page\n",
-                              sub_key + sub_ksize - end_of_subpage);
-                continue;
-              }
-
-              if ((options & C_COPYING) == 0) {
-                if (unlikely(sub_ksize != mc->mc_dbx->md_vlen_min)) {
-                  if (unlikely(sub_ksize < mc->mc_dbx->md_vlen_min ||
-                               sub_ksize > mc->mc_dbx->md_vlen_max)) {
-                    rc = bad_page(mp,
-                                  "nested-leaf2-key size (%zu) <> min/max "
-                                  "value-length (%zu/%zu)\n",
-                                  sub_ksize, mc->mc_dbx->md_vlen_min,
-                                  mc->mc_dbx->md_vlen_max);
-                    continue;
-                  }
-                  mc->mc_dbx->md_vlen_min = mc->mc_dbx->md_vlen_max = sub_ksize;
-                }
-                if ((options & C_SKIPORD) == 0) {
-                  sub_here.iov_len = sub_ksize;
-                  sub_here.iov_base = sub_key;
-                  if (sub_prev.iov_base &&
-                      unlikely(mc->mc_dbx->md_dcmp(&sub_prev, &sub_here) >= 0))
-                    rc = bad_page(mp, "nested-leaf2-key #%u wrong order\n", j);
-                  sub_prev = sub_here;
-                }
-              }
-            } else {
-              const MDBX_node *const sub_node = page_node(sp, j);
-              const char *sub_node_end = (char *)sub_node + NODESIZE;
-              if (unlikely(sub_node_end > end_of_subpage)) {
-                rc = bad_page(mp, "nested-node beyond (%zu) nested-page\n",
-                              end_of_subpage - sub_node_end);
-                continue;
-              }
-              if (unlikely(node_flags(sub_node) != 0))
-                rc = bad_page(mp, "nested-node invalid flags (%u)\n",
-                              node_flags(sub_node));
-
-              size_t sub_ksize = node_ks(sub_node);
-              char *sub_key = node_key(sub_node);
-              size_t sub_dsize = node_ds(sub_node);
-              /* char *sub_data = node_data(sub_node); */
-
-              if ((options & C_COPYING) == 0) {
-                if (unlikely(sub_ksize < mc->mc_dbx->md_vlen_min ||
-                             sub_ksize > mc->mc_dbx->md_vlen_max))
-                  rc = bad_page(mp,
-                                "nested-node-key size (%zu) <> min/max "
-                                "value-length (%zu/%zu)\n",
-                                sub_ksize, mc->mc_dbx->md_vlen_min,
-                                mc->mc_dbx->md_vlen_max);
-
-                if ((options & C_SKIPORD) == 0) {
-                  sub_here.iov_len = sub_ksize;
-                  sub_here.iov_base = sub_key;
-                  if (sub_prev.iov_base &&
-                      unlikely(mc->mc_dbx->md_dcmp(&sub_prev, &sub_here) >= 0))
-                    rc = bad_page(mp, "nested-node-key #%u wrong order\n", j);
-                  sub_prev = sub_here;
-                }
-              }
-              if (unlikely(sub_dsize != 0))
-                rc = bad_page(mp, "nested-node non-empty data size (%zu)\n",
-                              sub_dsize);
-              if (unlikely(end_of_subpage < sub_key + sub_ksize))
-                rc = bad_page(mp, "nested-node-key beyond (%zu) nested-page\n",
-                              sub_key + sub_ksize - end_of_subpage);
-            }
-          }
-        }
-        break;
-      }
-    }
-  }
-  return rc;
-}
-
-static __cold int mdbx_cursor_check(MDBX_cursor *mc, unsigned options) {
-  mdbx_tassert(mc->mc_txn, mc->mc_txn->mt_parent ||
-                               mc->mc_txn->tw.dirtyroom +
-                                       mc->mc_txn->tw.dirtylist->length ==
-                                   mc->mc_txn->mt_env->me_options.dp_limit);
-  mdbx_cassert(mc, mc->mc_top == mc->mc_snum - 1);
-  if (unlikely(mc->mc_top != mc->mc_snum - 1))
-    return MDBX_CURSOR_FULL;
-  mdbx_cassert(mc, (options & C_UPDATING) ? mc->mc_snum <= mc->mc_db->md_depth
-                                          : mc->mc_snum == mc->mc_db->md_depth);
-  if (unlikely((options & C_UPDATING) ? mc->mc_snum > mc->mc_db->md_depth
-                                      : mc->mc_snum != mc->mc_db->md_depth))
-    return MDBX_CURSOR_FULL;
-
-  for (int n = 0; n < (int)mc->mc_snum; ++n) {
-    MDBX_page *mp = mc->mc_pg[n];
-    const unsigned nkeys = page_numkeys(mp);
-    const bool expect_branch = (n < mc->mc_db->md_depth - 1) ? true : false;
-    const bool expect_nested_leaf =
-        (n + 1 == mc->mc_db->md_depth - 1) ? true : false;
-    const bool branch = IS_BRANCH(mp) ? true : false;
-    mdbx_cassert(mc, branch == expect_branch);
-    if (unlikely(branch != expect_branch))
-      return MDBX_CURSOR_FULL;
-    if ((options & C_UPDATING) == 0) {
-      mdbx_cassert(mc,
-                   nkeys > mc->mc_ki[n] || (!branch && nkeys == mc->mc_ki[n] &&
-                                            (mc->mc_flags & C_EOF) != 0));
-      if (unlikely(nkeys <= mc->mc_ki[n] &&
-                   !(!branch && nkeys == mc->mc_ki[n] &&
-                     (mc->mc_flags & C_EOF) != 0)))
-        return MDBX_CURSOR_FULL;
-    } else {
-      mdbx_cassert(mc, nkeys + 1 >= mc->mc_ki[n]);
-      if (unlikely(nkeys + 1 < mc->mc_ki[n]))
-        return MDBX_CURSOR_FULL;
-    }
-
-    int err = mdbx_page_check(mc, mp, options);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-
-    for (unsigned i = 0; i < nkeys; ++i) {
-      if (branch) {
-        MDBX_node *node = page_node(mp, i);
-        mdbx_cassert(mc, node_flags(node) == 0);
-        if (unlikely(node_flags(node) != 0))
-          return MDBX_CURSOR_FULL;
-        pgno_t pgno = node_pgno(node);
-        MDBX_page *np;
-        int rc =
-            mdbx_page_get(mc, pgno, &np, NULL, pp_txnid4chk(mp, mc->mc_txn));
-        mdbx_cassert(mc, rc == MDBX_SUCCESS);
-        if (unlikely(rc != MDBX_SUCCESS))
-          return rc;
-        const bool nested_leaf = IS_LEAF(np) ? true : false;
-        mdbx_cassert(mc, nested_leaf == expect_nested_leaf);
-        if (unlikely(nested_leaf != expect_nested_leaf))
-          return MDBX_CURSOR_FULL;
-        err = mdbx_page_check(mc, np, options);
-        if (unlikely(err != MDBX_SUCCESS))
-          return err;
-      }
-    }
-  }
-  return MDBX_SUCCESS;
-}
-
-/* Complete a delete operation started by mdbx_cursor_del(). */
-static int mdbx_cursor_del0(MDBX_cursor *mc) {
-  int rc;
-  MDBX_page *mp;
-  indx_t ki;
-  unsigned nkeys;
-  MDBX_dbi dbi = mc->mc_dbi;
-
-  mdbx_cassert(mc, cursor_is_tracked(mc));
-  mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
-  ki = mc->mc_ki[mc->mc_top];
-  mp = mc->mc_pg[mc->mc_top];
-  mdbx_node_del(mc, mc->mc_db->md_xsize);
-  mc->mc_db->md_entries--;
-
-  /* Adjust other cursors pointing to mp */
-  for (MDBX_cursor *m2 = mc->mc_txn->tw.cursors[dbi]; m2; m2 = m2->mc_next) {
-    MDBX_cursor *m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-    if (m3 == mc || !(m2->mc_flags & m3->mc_flags & C_INITIALIZED))
-      continue;
-    if (m3->mc_snum < mc->mc_snum)
-      continue;
-    if (m3->mc_pg[mc->mc_top] == mp) {
-      if (m3->mc_ki[mc->mc_top] == ki) {
-        m3->mc_flags |= C_DEL;
-        if (mc->mc_db->md_flags & MDBX_DUPSORT) {
-          /* Sub-cursor referred into dataset which is gone */
-          m3->mc_xcursor->mx_cursor.mc_flags &= ~(C_INITIALIZED | C_EOF);
-        }
-        continue;
-      } else if (m3->mc_ki[mc->mc_top] > ki) {
-        m3->mc_ki[mc->mc_top]--;
-      }
-      if (XCURSOR_INITED(m3))
-        XCURSOR_REFRESH(m3, m3->mc_pg[mc->mc_top], m3->mc_ki[mc->mc_top]);
-    }
-  }
-
-  rc = mdbx_rebalance(mc);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto bailout;
-
-  if (unlikely(!mc->mc_snum)) {
-    /* DB is totally empty now, just bail out.
-     * Other cursors adjustments were already done
-     * by mdbx_rebalance and aren't needed here. */
-    mdbx_cassert(mc, mc->mc_db->md_entries == 0 && mc->mc_db->md_depth == 0 &&
-                         mc->mc_db->md_root == P_INVALID);
-    mc->mc_flags |= C_EOF;
-    return MDBX_SUCCESS;
-  }
-
-  ki = mc->mc_ki[mc->mc_top];
-  mp = mc->mc_pg[mc->mc_top];
-  mdbx_cassert(mc, IS_LEAF(mc->mc_pg[mc->mc_top]));
-  nkeys = page_numkeys(mp);
-  mdbx_cassert(mc, (mc->mc_db->md_entries > 0 && nkeys > 0) ||
-                       ((mc->mc_flags & C_SUB) && mc->mc_db->md_entries == 0 &&
-                        nkeys == 0));
-
-  /* Adjust this and other cursors pointing to mp */
-  for (MDBX_cursor *m2 = mc->mc_txn->tw.cursors[dbi]; m2; m2 = m2->mc_next) {
-    MDBX_cursor *m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-    if (!(m2->mc_flags & m3->mc_flags & C_INITIALIZED))
-      continue;
-    if (m3->mc_snum < mc->mc_snum)
-      continue;
-    if (m3->mc_pg[mc->mc_top] == mp) {
-      /* if m3 points past last node in page, find next sibling */
-      if (m3->mc_ki[mc->mc_top] >= nkeys) {
-        rc = mdbx_cursor_sibling(m3, SIBLING_RIGHT);
-        if (rc == MDBX_NOTFOUND) {
-          m3->mc_flags |= C_EOF;
-          rc = MDBX_SUCCESS;
-          continue;
-        }
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      }
-      if (m3->mc_ki[mc->mc_top] >= ki ||
-          /* moved to right sibling */ m3->mc_pg[mc->mc_top] != mp) {
-        if (m3->mc_xcursor && !(m3->mc_flags & C_EOF)) {
-          MDBX_node *node =
-              page_node(m3->mc_pg[m3->mc_top], m3->mc_ki[m3->mc_top]);
-          /* If this node has dupdata, it may need to be reinited
-           * because its data has moved.
-           * If the xcursor was not inited it must be reinited.
-           * Else if node points to a subDB, nothing is needed. */
-          if (node_flags(node) & F_DUPDATA) {
-            if (m3->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
-              if (!(node_flags(node) & F_SUBDATA))
-                m3->mc_xcursor->mx_cursor.mc_pg[0] = node_data(node);
-            } else {
-              rc = mdbx_xcursor_init1(m3, node, m3->mc_pg[m3->mc_top]);
-              if (unlikely(rc != MDBX_SUCCESS))
-                goto bailout;
-              rc = mdbx_cursor_first(&m3->mc_xcursor->mx_cursor, NULL, NULL);
-              if (unlikely(rc != MDBX_SUCCESS))
-                goto bailout;
-            }
-          }
-          m3->mc_xcursor->mx_cursor.mc_flags |= C_DEL;
-        }
-        m3->mc_flags |= C_DEL;
-      }
-    }
-  }
-
-  mdbx_cassert(mc, rc == MDBX_SUCCESS);
-  if (mdbx_audit_enabled())
-    rc = mdbx_cursor_check(mc, 0);
-  return rc;
-
-bailout:
-  mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-  return rc;
-}
-
-int mdbx_del(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-             const MDBX_val *data) {
-  int rc = check_txn_rw(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!key))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
-    return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
-
-  return mdbx_del0(txn, dbi, key, data, 0);
-}
-
-static int mdbx_del0(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                     const MDBX_val *data, unsigned flags) {
-  MDBX_cursor_couple cx;
-  MDBX_cursor_op op;
-  MDBX_val rdata;
-  int rc, exact = 0;
-  DKBUF;
-
-  mdbx_debug("====> delete db %u key [%s], data [%s]", dbi, DKEY(key),
-             DVAL(data));
-
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (data) {
-    op = MDBX_GET_BOTH;
-    rdata = *data;
-    data = &rdata;
-  } else {
-    op = MDBX_SET;
-    flags |= MDBX_ALLDUPS;
-  }
-  rc =
-      mdbx_cursor_set(&cx.outer, (MDBX_val *)key, (MDBX_val *)data, op, &exact);
-  if (likely(rc == MDBX_SUCCESS)) {
-    /* let mdbx_page_split know about this cursor if needed:
-     * delete will trigger a rebalance; if it needs to move
-     * a node from one page to another, it will have to
-     * update the parent's separator key(s). If the new sepkey
-     * is larger than the current one, the parent page may
-     * run out of space, triggering a split. We need this
-     * cursor to be consistent until the end of the rebalance. */
-    cx.outer.mc_next = txn->tw.cursors[dbi];
-    txn->tw.cursors[dbi] = &cx.outer;
-    rc = mdbx_cursor_del(&cx.outer, flags);
-    txn->tw.cursors[dbi] = cx.outer.mc_next;
-  }
-  return rc;
-}
-
-/* Split a page and insert a new node.
- * Set MDBX_TXN_ERROR on failure.
- * [in,out] mc Cursor pointing to the page and desired insertion index.
- * The cursor will be updated to point to the actual page and index where
- * the node got inserted after the split.
- * [in] newkey The key for the newly inserted node.
- * [in] newdata The data for the newly inserted node.
- * [in] newpgno The page number, if the new node is a branch node.
- * [in] nflags The NODE_ADD_FLAGS for the new node.
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_page_split(MDBX_cursor *mc, const MDBX_val *newkey,
-                           MDBX_val *newdata, pgno_t newpgno, unsigned nflags) {
-  unsigned flags;
-  int rc = MDBX_SUCCESS, foliage = 0, did_split = 0;
-  pgno_t pgno = 0;
-  unsigned i, ptop;
-  MDBX_env *env = mc->mc_txn->mt_env;
-  MDBX_val sepkey, rkey, xdata;
-  MDBX_page *copy = NULL;
-  MDBX_page *rp, *pp;
-  MDBX_cursor mn;
-  DKBUF;
-
-  MDBX_page *mp = mc->mc_pg[mc->mc_top];
-  unsigned newindx = mc->mc_ki[mc->mc_top];
-  unsigned nkeys = page_numkeys(mp);
-  if (mdbx_audit_enabled()) {
-    rc = mdbx_cursor_check(mc, C_UPDATING);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  mdbx_cassert(mc,
-               nkeys >= (unsigned)(IS_BRANCH(mp) ? MDBX_MINKEYS * 2 - 1 : 1));
-  mdbx_debug("-----> splitting %s page %" PRIaPGNO
-             " and adding [%s] at index %i/%i",
-             IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno, DKEY(newkey),
-             mc->mc_ki[mc->mc_top], nkeys);
-
-  /* Create a right sibling. */
-  if ((rc = mdbx_page_new(mc, mp->mp_flags, 1, &rp)))
-    return rc;
-  rp->mp_leaf2_ksize = mp->mp_leaf2_ksize;
-  mdbx_debug("new right sibling: page %" PRIaPGNO, rp->mp_pgno);
-
-  /* Usually when splitting the root page, the cursor
-   * height is 1. But when called from mdbx_update_key,
-   * the cursor height may be greater because it walks
-   * up the stack while finding the branch slot to update. */
-  if (mc->mc_top < 1) {
-    if ((rc = mdbx_page_new(mc, P_BRANCH, 1, &pp)))
-      goto done;
-    /* shift current top to make room for new parent */
-    mdbx_cassert(mc, mc->mc_snum < 2 && mc->mc_db->md_depth > 0);
-    mc->mc_pg[2] = mc->mc_pg[1];
-    mc->mc_ki[2] = mc->mc_ki[1];
-    mc->mc_pg[1] = mc->mc_pg[0];
-    mc->mc_ki[1] = mc->mc_ki[0];
-    mc->mc_pg[0] = pp;
-    mc->mc_ki[0] = 0;
-    mc->mc_db->md_root = pp->mp_pgno;
-    mdbx_debug("root split! new root = %" PRIaPGNO, pp->mp_pgno);
-    foliage = mc->mc_db->md_depth++;
-
-    /* Add left (implicit) pointer. */
-    if (unlikely((rc = mdbx_node_add_branch(mc, 0, NULL, mp->mp_pgno)) !=
-                 MDBX_SUCCESS)) {
-      /* undo the pre-push */
-      mc->mc_pg[0] = mc->mc_pg[1];
-      mc->mc_ki[0] = mc->mc_ki[1];
-      mc->mc_db->md_root = mp->mp_pgno;
-      mc->mc_db->md_depth--;
-      goto done;
-    }
-    mc->mc_snum++;
-    mc->mc_top++;
-    ptop = 0;
-  } else {
-    ptop = mc->mc_top - 1;
-    mdbx_debug("parent branch page is %" PRIaPGNO, mc->mc_pg[ptop]->mp_pgno);
-  }
-
-  cursor_copy_internal(mc, &mn);
-  mn.mc_xcursor = NULL;
-  mn.mc_pg[mn.mc_top] = rp;
-  mn.mc_ki[mn.mc_top] = 0;
-  mn.mc_ki[ptop] = mc->mc_ki[ptop] + 1;
-
-  unsigned split_indx;
-  if (nflags & MDBX_APPEND) {
-    mn.mc_ki[mn.mc_top] = 0;
-    sepkey = *newkey;
-    split_indx = newindx;
-    nkeys = 0;
-  } else {
-    split_indx = (nkeys + 1) / 2;
-    if (IS_LEAF2(rp)) {
-      char *split, *ins;
-      unsigned lsize, rsize, ksize;
-      /* Move half of the keys to the right sibling */
-      const int x = mc->mc_ki[mc->mc_top] - split_indx;
-      ksize = mc->mc_db->md_xsize;
-      split = page_leaf2key(mp, split_indx, ksize);
-      rsize = (nkeys - split_indx) * ksize;
-      lsize = (nkeys - split_indx) * sizeof(indx_t);
-      mdbx_cassert(mc, mp->mp_lower >= lsize);
-      mp->mp_lower -= (indx_t)lsize;
-      mdbx_cassert(mc, rp->mp_lower + lsize <= UINT16_MAX);
-      rp->mp_lower += (indx_t)lsize;
-      mdbx_cassert(mc, mp->mp_upper + rsize - lsize <= UINT16_MAX);
-      mp->mp_upper += (indx_t)(rsize - lsize);
-      mdbx_cassert(mc, rp->mp_upper >= rsize - lsize);
-      rp->mp_upper -= (indx_t)(rsize - lsize);
-      sepkey.iov_len = ksize;
-      if (newindx == split_indx) {
-        sepkey.iov_base = newkey->iov_base;
-      } else {
-        sepkey.iov_base = split;
-      }
-      if (x < 0) {
-        mdbx_cassert(mc, ksize >= sizeof(indx_t));
-        ins = page_leaf2key(mp, mc->mc_ki[mc->mc_top], ksize);
-        memcpy(rp->mp_ptrs, split, rsize);
-        sepkey.iov_base = rp->mp_ptrs;
-        memmove(ins + ksize, ins, (split_indx - mc->mc_ki[mc->mc_top]) * ksize);
-        memcpy(ins, newkey->iov_base, ksize);
-        mdbx_cassert(mc, UINT16_MAX - mp->mp_lower >= (int)sizeof(indx_t));
-        mp->mp_lower += sizeof(indx_t);
-        mdbx_cassert(mc, mp->mp_upper >= ksize - sizeof(indx_t));
-        mp->mp_upper -= (indx_t)(ksize - sizeof(indx_t));
-      } else {
-        memcpy(rp->mp_ptrs, split, x * ksize);
-        ins = page_leaf2key(rp, x, ksize);
-        memcpy(ins, newkey->iov_base, ksize);
-        memcpy(ins + ksize, split + x * ksize, rsize - x * ksize);
-        mdbx_cassert(mc, UINT16_MAX - rp->mp_lower >= (int)sizeof(indx_t));
-        rp->mp_lower += sizeof(indx_t);
-        mdbx_cassert(mc, rp->mp_upper >= ksize - sizeof(indx_t));
-        rp->mp_upper -= (indx_t)(ksize - sizeof(indx_t));
-        mdbx_cassert(mc, x <= (int)UINT16_MAX);
-        mc->mc_ki[mc->mc_top] = (indx_t)x;
-      }
-    } else {
-      /* Maximum free space in an empty page */
-      const unsigned pmax = page_space(env);
-      const size_t nsize = IS_LEAF(mp) ? leaf_size(env, newkey, newdata)
-                                       : branch_size(env, newkey);
-
-      /* grab a page to hold a temporary copy */
-      copy = mdbx_page_malloc(mc->mc_txn, 1);
-      if (unlikely(copy == NULL)) {
-        rc = MDBX_ENOMEM;
-        goto done;
-      }
-      copy->mp_pgno = mp->mp_pgno;
-      copy->mp_flags = mp->mp_flags;
-      copy->mp_txnid = INVALID_TXNID;
-      copy->mp_lower = 0;
-      copy->mp_upper = (indx_t)page_space(env);
-
-      /* prepare to insert */
-      for (unsigned j = i = 0; i < nkeys; i++) {
-        if (i == newindx)
-          copy->mp_ptrs[j++] = 0;
-        copy->mp_ptrs[j++] = mp->mp_ptrs[i];
-      }
-
-      /* When items are relatively large the split point needs
-       * to be checked, because being off-by-one will make the
-       * difference between success or failure in mdbx_node_add.
-       *
-       * It's also relevant if a page happens to be laid out
-       * such that one half of its nodes are all "small" and
-       * the other half of its nodes are "large." If the new
-       * item is also "large" and falls on the half with
-       * "large" nodes, it also may not fit.
-       *
-       * As a final tweak, if the new item goes on the last
-       * spot on the page (and thus, onto the new page), bias
-       * the split so the new page is emptier than the old page.
-       * This yields better packing during sequential inserts. */
-      if (nkeys < 32 || nsize > pmax / 16 || newindx >= nkeys) {
-        /* Find split point */
-        int dir;
-        size_t psize = 0;
-        unsigned k;
-        if (newindx <= split_indx || newindx >= nkeys) {
-          i = 0;
-          dir = 1;
-          k = (newindx >= nkeys) ? nkeys : split_indx + 1 + IS_LEAF(mp);
-          split_indx = k - 1;
-        } else {
-          i = nkeys;
-          dir = -1;
-          k = split_indx - 1;
-          split_indx += 1;
-        }
-        do {
-          if (i == newindx) {
-            psize += nsize;
-          } else {
-            MDBX_node *node =
-                (MDBX_node *)((char *)mp + copy->mp_ptrs[i] + PAGEHDRSZ);
-            psize += NODESIZE + node_ks(node) + sizeof(indx_t);
-            if (IS_LEAF(mp))
-              psize += F_ISSET(node_flags(node), F_BIGDATA) ? sizeof(pgno_t)
-                                                            : node_ds(node);
-            psize = EVEN(psize);
-          }
-          if (psize > pmax) {
-            split_indx = i + (dir < 0);
-            break;
-          }
-          i += dir;
-        } while (i != k);
-      }
-
-      if (split_indx == newindx) {
-        sepkey.iov_len = newkey->iov_len;
-        sepkey.iov_base = newkey->iov_base;
-      } else {
-        MDBX_node *node =
-            (MDBX_node *)((char *)mp + copy->mp_ptrs[split_indx] + PAGEHDRSZ);
-        sepkey.iov_len = node_ks(node);
-        sepkey.iov_base = node_key(node);
-      }
-    }
-  }
-
-  mdbx_debug("separator is %d [%s]", split_indx, DKEY(&sepkey));
-  if (mdbx_audit_enabled()) {
-    rc = mdbx_cursor_check(mc, C_UPDATING);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto done;
-    rc = mdbx_cursor_check(&mn, C_UPDATING);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto done;
-  }
-
-  /* Copy separator key to the parent. */
-  if (page_room(mn.mc_pg[ptop]) < branch_size(env, &sepkey)) {
-    const int snum = mc->mc_snum;
-    const int depth = mc->mc_db->md_depth;
-    mn.mc_snum--;
-    mn.mc_top--;
-    did_split = 1;
-    /* We want other splits to find mn when doing fixups */
-    WITH_CURSOR_TRACKING(
-        mn, rc = mdbx_page_split(&mn, &sepkey, NULL, rp->mp_pgno, 0));
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto done;
-    mdbx_cassert(mc, (int)mc->mc_snum - snum == mc->mc_db->md_depth - depth);
-    if (mdbx_audit_enabled()) {
-      rc = mdbx_cursor_check(mc, C_UPDATING);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto done;
-    }
-
-    /* root split? */
-    ptop += mc->mc_snum - snum;
-
-    /* Right page might now have changed parent.
-     * Check if left page also changed parent. */
-    if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
-        mc->mc_ki[ptop] >= page_numkeys(mc->mc_pg[ptop])) {
-      for (i = 0; i < ptop; i++) {
-        mc->mc_pg[i] = mn.mc_pg[i];
-        mc->mc_ki[i] = mn.mc_ki[i];
-      }
-      mc->mc_pg[ptop] = mn.mc_pg[ptop];
-      if (mn.mc_ki[ptop]) {
-        mc->mc_ki[ptop] = mn.mc_ki[ptop] - 1;
-      } else {
-        /* find right page's left sibling */
-        mc->mc_ki[ptop] = mn.mc_ki[ptop];
-        rc = mdbx_cursor_sibling(mc, SIBLING_LEFT);
-      }
-    }
-  } else {
-    mn.mc_top--;
-    rc = mdbx_node_add_branch(&mn, mn.mc_ki[ptop], &sepkey, rp->mp_pgno);
-    mn.mc_top++;
-  }
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (rc == MDBX_NOTFOUND) /* improper mdbx_cursor_sibling() result */ {
-      mdbx_error("unexpected %s", "MDBX_NOTFOUND");
-      rc = MDBX_PROBLEM;
-    }
-    goto done;
-  }
-
-  if (nflags & MDBX_APPEND) {
-    mc->mc_pg[mc->mc_top] = rp;
-    mc->mc_ki[mc->mc_top] = 0;
-    switch (PAGETYPE(rp)) {
-    case P_BRANCH: {
-      mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0);
-      mdbx_cassert(mc, newpgno != 0 && newpgno != P_INVALID);
-      rc = mdbx_node_add_branch(mc, 0, newkey, newpgno);
-    } break;
-    case P_LEAF: {
-      mdbx_cassert(mc, newpgno == 0 || newpgno == P_INVALID);
-      rc = mdbx_node_add_leaf(mc, 0, newkey, newdata, nflags);
-    } break;
-    case P_LEAF | P_LEAF2: {
-      mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0);
-      mdbx_cassert(mc, newpgno == 0 || newpgno == P_INVALID);
-      rc = mdbx_node_add_leaf2(mc, 0, newkey);
-    } break;
-    default:
-      rc = bad_page(rp, "wrong page-type %u\n", PAGETYPE(rp));
-    }
-    if (rc)
-      goto done;
-    for (i = 0; i < mc->mc_top; i++)
-      mc->mc_ki[i] = mn.mc_ki[i];
-  } else if (!IS_LEAF2(mp)) {
-    /* Move nodes */
-    mc->mc_pg[mc->mc_top] = rp;
-    i = split_indx;
-    indx_t n = 0;
-    do {
-      MDBX_val *rdata = NULL;
-      if (i == newindx) {
-        rkey.iov_base = newkey->iov_base;
-        rkey.iov_len = newkey->iov_len;
-        if (IS_LEAF(mp)) {
-          rdata = newdata;
-        } else
-          pgno = newpgno;
-        flags = nflags;
-        /* Update index for the new key. */
-        mc->mc_ki[mc->mc_top] = n;
-      } else {
-        MDBX_node *node =
-            (MDBX_node *)((char *)mp + copy->mp_ptrs[i] + PAGEHDRSZ);
-        rkey.iov_base = node_key(node);
-        rkey.iov_len = node_ks(node);
-        if (IS_LEAF(mp)) {
-          xdata.iov_base = node_data(node);
-          xdata.iov_len = node_ds(node);
-          rdata = &xdata;
-        } else
-          pgno = node_pgno(node);
-        flags = node_flags(node);
-      }
-
-      switch (PAGETYPE(rp)) {
-      case P_BRANCH: {
-        mdbx_cassert(mc, 0 == (uint16_t)flags);
-        if (n == 0) {
-          /* First branch index doesn't need key data. */
-          rkey.iov_len = 0;
-        }
-        rc = mdbx_node_add_branch(mc, n, &rkey, pgno);
-      } break;
-      case P_LEAF: {
-        mdbx_cassert(mc, pgno == 0);
-        mdbx_cassert(mc, rdata != NULL);
-        rc = mdbx_node_add_leaf(mc, n, &rkey, rdata, flags);
-      } break;
-      /* case P_LEAF | P_LEAF2: {
-        mdbx_cassert(mc, (nflags & (F_BIGDATA | F_SUBDATA | F_DUPDATA)) == 0);
-        mdbx_cassert(mc, gno == 0);
-        rc = mdbx_node_add_leaf2(mc, n, &rkey);
-      } break; */
-      default:
-        rc = bad_page(rp, "wrong page-type %u\n", PAGETYPE(rp));
-      }
-      if (rc)
-        goto done;
-
-      if (i == nkeys) {
-        i = 0;
-        n = 0;
-        mc->mc_pg[mc->mc_top] = copy;
-      } else {
-        i++;
-        n++;
-      }
-    } while (i != split_indx);
-
-    nkeys = page_numkeys(copy);
-    for (i = 0; i < nkeys; i++)
-      mp->mp_ptrs[i] = copy->mp_ptrs[i];
-    mp->mp_lower = copy->mp_lower;
-    mp->mp_upper = copy->mp_upper;
-    memcpy(page_node(mp, nkeys - 1), page_node(copy, nkeys - 1),
-           env->me_psize - copy->mp_upper - PAGEHDRSZ);
-
-    /* reset back to original page */
-    if (newindx < split_indx) {
-      mc->mc_pg[mc->mc_top] = mp;
-    } else {
-      mc->mc_pg[mc->mc_top] = rp;
-      mc->mc_ki[ptop]++;
-      /* Make sure mc_ki is still valid. */
-      if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
-          mc->mc_ki[ptop] >= page_numkeys(mc->mc_pg[ptop])) {
-        for (i = 0; i <= ptop; i++) {
-          mc->mc_pg[i] = mn.mc_pg[i];
-          mc->mc_ki[i] = mn.mc_ki[i];
-        }
-      }
-    }
-    if (nflags & MDBX_RESERVE) {
-      MDBX_node *node = page_node(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
-      if (!(node_flags(node) & F_BIGDATA))
-        newdata->iov_base = node_data(node);
-    }
-  } else {
-    if (newindx >= split_indx) {
-      mc->mc_pg[mc->mc_top] = rp;
-      mc->mc_ki[ptop]++;
-      /* Make sure mc_ki is still valid. */
-      if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
-          mc->mc_ki[ptop] >= page_numkeys(mc->mc_pg[ptop])) {
-        for (i = 0; i <= ptop; i++) {
-          mc->mc_pg[i] = mn.mc_pg[i];
-          mc->mc_ki[i] = mn.mc_ki[i];
-        }
-      }
-    }
-  }
-
-  {
-    /* Adjust other cursors pointing to mp */
-    MDBX_cursor *m2, *m3;
-    MDBX_dbi dbi = mc->mc_dbi;
-    nkeys = page_numkeys(mp);
-
-    for (m2 = mc->mc_txn->tw.cursors[dbi]; m2; m2 = m2->mc_next) {
-      m3 = (mc->mc_flags & C_SUB) ? &m2->mc_xcursor->mx_cursor : m2;
-      if (m3 == mc)
-        continue;
-      if (!(m2->mc_flags & m3->mc_flags & C_INITIALIZED))
-        continue;
-      if (foliage) {
-        int k;
-        /* sub cursors may be on different DB */
-        if (m3->mc_pg[0] != mp)
-          continue;
-        /* root split */
-        for (k = foliage; k >= 0; k--) {
-          m3->mc_ki[k + 1] = m3->mc_ki[k];
-          m3->mc_pg[k + 1] = m3->mc_pg[k];
-        }
-        m3->mc_ki[0] = (m3->mc_ki[0] >= nkeys) ? 1 : 0;
-        m3->mc_pg[0] = mc->mc_pg[0];
-        m3->mc_snum++;
-        m3->mc_top++;
-      }
-      if (m3->mc_top >= mc->mc_top && m3->mc_pg[mc->mc_top] == mp) {
-        if (m3->mc_ki[mc->mc_top] >= newindx && !(nflags & MDBX_SPLIT_REPLACE))
-          m3->mc_ki[mc->mc_top]++;
-        if (m3->mc_ki[mc->mc_top] >= nkeys) {
-          m3->mc_pg[mc->mc_top] = rp;
-          mdbx_cassert(mc, m3->mc_ki[mc->mc_top] >= nkeys);
-          m3->mc_ki[mc->mc_top] -= (indx_t)nkeys;
-          for (i = 0; i < mc->mc_top; i++) {
-            m3->mc_ki[i] = mn.mc_ki[i];
-            m3->mc_pg[i] = mn.mc_pg[i];
-          }
-        }
-      } else if (!did_split && m3->mc_top >= ptop &&
-                 m3->mc_pg[ptop] == mc->mc_pg[ptop] &&
-                 m3->mc_ki[ptop] >= mc->mc_ki[ptop]) {
-        m3->mc_ki[ptop]++;
-      }
-      if (XCURSOR_INITED(m3) && IS_LEAF(mp))
-        XCURSOR_REFRESH(m3, m3->mc_pg[mc->mc_top], m3->mc_ki[mc->mc_top]);
-    }
-  }
-  mdbx_debug("mp left: %d, rp left: %d", page_room(mp), page_room(rp));
-
-done:
-  if (copy) /* tmp page */
-    mdbx_dpage_free(env, copy, 1);
-  if (unlikely(rc))
-    mc->mc_txn->mt_flags |= MDBX_TXN_ERROR;
-  return rc;
-}
-
-int mdbx_put(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key, MDBX_val *data,
-             unsigned flags) {
-  int rc = check_txn_rw(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!key || !data))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(flags & ~(MDBX_NOOVERWRITE | MDBX_NODUPDATA | MDBX_ALLDUPS |
-                         MDBX_ALLDUPS | MDBX_RESERVE | MDBX_APPEND |
-                         MDBX_APPENDDUP | MDBX_CURRENT | MDBX_MULTIPLE)))
-    return MDBX_EINVAL;
-
-  if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
-    return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
-
-  MDBX_cursor_couple cx;
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  cx.outer.mc_next = txn->tw.cursors[dbi];
-  txn->tw.cursors[dbi] = &cx.outer;
-
-  /* LY: support for update (explicit overwrite) */
-  if (flags & MDBX_CURRENT) {
-    rc = mdbx_cursor_get(&cx.outer, (MDBX_val *)key, NULL, MDBX_SET);
-    if (likely(rc == MDBX_SUCCESS) &&
-        (txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT) &&
-        (flags & MDBX_ALLDUPS) == 0) {
-      /* LY: allows update (explicit overwrite) only for unique keys */
-      MDBX_node *node = page_node(cx.outer.mc_pg[cx.outer.mc_top],
-                                  cx.outer.mc_ki[cx.outer.mc_top]);
-      if (F_ISSET(node_flags(node), F_DUPDATA)) {
-        mdbx_tassert(txn, XCURSOR_INITED(&cx.outer) &&
-                              cx.outer.mc_xcursor->mx_db.md_entries > 1);
-        rc = MDBX_EMULTIVAL;
-      }
-    }
-  }
-
-  if (likely(rc == MDBX_SUCCESS))
-    rc = mdbx_cursor_put(&cx.outer, key, data, flags);
-  txn->tw.cursors[dbi] = cx.outer.mc_next;
-
-  return rc;
-}
-
-/**** COPYING *****************************************************************/
-
-#ifndef MDBX_WBUF
-#define MDBX_WBUF ((size_t)1024 * 1024)
-#endif
-
-/* State needed for a double-buffering compacting copy. */
-typedef struct mdbx_copy {
-  MDBX_env *mc_env;
-  MDBX_txn *mc_txn;
-  mdbx_condpair_t mc_condpair;
-  uint8_t *mc_wbuf[2];
-  uint8_t *mc_over[2];
-  size_t mc_wlen[2];
-  size_t mc_olen[2];
-  mdbx_filehandle_t mc_fd;
-  /* Error code.  Never cleared if set.  Both threads can set nonzero
-   * to fail the copy.  Not mutex-protected, MDBX expects atomic int. */
-  volatile int mc_error;
-  pgno_t mc_next_pgno;
-  volatile unsigned mc_head;
-  volatile unsigned mc_tail;
-} mdbx_copy;
-
-/* Dedicated writer thread for compacting copy. */
-static THREAD_RESULT __cold THREAD_CALL mdbx_env_copythr(void *arg) {
-  mdbx_copy *my = arg;
-
-#if defined(EPIPE) && !(defined(_WIN32) || defined(_WIN64))
-  sigset_t sigset;
-  sigemptyset(&sigset);
-  sigaddset(&sigset, SIGPIPE);
-  my->mc_error = pthread_sigmask(SIG_BLOCK, &sigset, NULL);
-#endif /* EPIPE */
-
-  mdbx_condpair_lock(&my->mc_condpair);
-  while (!my->mc_error) {
-    while (my->mc_tail == my->mc_head && !my->mc_error) {
-      int err = mdbx_condpair_wait(&my->mc_condpair, true);
-      if (err != MDBX_SUCCESS) {
-        my->mc_error = err;
-        goto bailout;
-      }
-    }
-    const unsigned toggle = my->mc_tail & 1;
-    size_t wsize = my->mc_wlen[toggle];
-    if (wsize == 0) {
-      my->mc_tail += 1;
-      break /* EOF */;
-    }
-    my->mc_wlen[toggle] = 0;
-    uint8_t *ptr = my->mc_wbuf[toggle];
-  again:
-    if (!my->mc_error) {
-      int err = mdbx_write(my->mc_fd, ptr, wsize);
-      if (err != MDBX_SUCCESS) {
-#if defined(EPIPE) && !(defined(_WIN32) || defined(_WIN64))
-        if (err == EPIPE) {
-          /* Collect the pending SIGPIPE,
-           * otherwise at least OS X gives it to the process on thread-exit. */
-          int unused;
-          sigwait(&sigset, &unused);
-        }
-#endif /* EPIPE */
-        my->mc_error = err;
-        goto bailout;
-      }
-    }
-
-    /* If there's an overflow page tail, write it too */
-    wsize = my->mc_olen[toggle];
-    if (wsize) {
-      my->mc_olen[toggle] = 0;
-      ptr = my->mc_over[toggle];
-      goto again;
-    }
-    my->mc_tail += 1;
-    mdbx_condpair_signal(&my->mc_condpair, false);
-  }
-bailout:
-  mdbx_condpair_unlock(&my->mc_condpair);
-  return (THREAD_RESULT)0;
-}
-
-/* Give buffer and/or MDBX_EOF to writer thread, await unused buffer. */
-static __cold int mdbx_env_cthr_toggle(mdbx_copy *my) {
-  mdbx_condpair_lock(&my->mc_condpair);
-  mdbx_assert(my->mc_env, my->mc_head - my->mc_tail < 2 || my->mc_error);
-  my->mc_head += 1;
-  mdbx_condpair_signal(&my->mc_condpair, true);
-  while (!my->mc_error &&
-         my->mc_head - my->mc_tail == 2 /* both buffers in use */) {
-    int err = mdbx_condpair_wait(&my->mc_condpair, false);
-    if (err != MDBX_SUCCESS)
-      my->mc_error = err;
-  }
-  mdbx_condpair_unlock(&my->mc_condpair);
-  return my->mc_error;
-}
-
-/* Depth-first tree traversal for compacting copy.
- * [in] my control structure.
- * [in,out] pg database root.
- * [in] flags includes F_DUPDATA if it is a sorted-duplicate sub-DB. */
-static __cold int mdbx_env_cwalk(mdbx_copy *my, pgno_t *pg, int flags) {
-  MDBX_cursor_couple couple;
-  MDBX_page *mo, *mp, *leaf;
-  char *buf, *ptr;
-  int rc;
-  unsigned i;
-
-  /* Empty DB, nothing to do */
-  if (*pg == P_INVALID)
-    return MDBX_SUCCESS;
-
-  memset(&couple, 0, sizeof(couple));
-  couple.outer.mc_snum = 1;
-  couple.outer.mc_txn = my->mc_txn;
-  couple.outer.mc_flags = couple.inner.mx_cursor.mc_flags =
-      C_COPYING | C_SKIPORD;
-
-  rc = mdbx_page_get(&couple.outer, *pg, &couple.outer.mc_pg[0], NULL,
-                     my->mc_txn->mt_txnid);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  rc = mdbx_page_search_root(&couple.outer, NULL, MDBX_PS_FIRST);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  /* Make cursor pages writable */
-  buf = ptr = mdbx_malloc(pgno2bytes(my->mc_env, couple.outer.mc_snum));
-  if (buf == NULL)
-    return MDBX_ENOMEM;
-
-  for (i = 0; i < couple.outer.mc_top; i++) {
-    mdbx_page_copy((MDBX_page *)ptr, couple.outer.mc_pg[i],
-                   my->mc_env->me_psize);
-    couple.outer.mc_pg[i] = (MDBX_page *)ptr;
-    ptr += my->mc_env->me_psize;
-  }
-
-  /* This is writable space for a leaf page. Usually not needed. */
-  leaf = (MDBX_page *)ptr;
-
-  while (couple.outer.mc_snum > 0) {
-    mp = couple.outer.mc_pg[couple.outer.mc_top];
-    unsigned n = page_numkeys(mp);
-
-    if (IS_LEAF(mp)) {
-      if (!IS_LEAF2(mp) && !(flags & F_DUPDATA)) {
-        for (i = 0; i < n; i++) {
-          MDBX_node *node = page_node(mp, i);
-          if (node_flags(node) & F_BIGDATA) {
-            MDBX_page *omp;
-
-            /* Need writable leaf */
-            if (mp != leaf) {
-              couple.outer.mc_pg[couple.outer.mc_top] = leaf;
-              mdbx_page_copy(leaf, mp, my->mc_env->me_psize);
-              mp = leaf;
-              node = page_node(mp, i);
-            }
-
-            const pgno_t pgno = node_largedata_pgno(node);
-            poke_pgno(node_data(node), my->mc_next_pgno);
-            rc = mdbx_page_get(&couple.outer, pgno, &omp, NULL,
-                               pp_txnid4chk(mp, my->mc_txn));
-            if (unlikely(rc != MDBX_SUCCESS))
-              goto done;
-            unsigned toggle = my->mc_head & 1;
-            if (my->mc_wlen[toggle] + my->mc_env->me_psize > MDBX_WBUF) {
-              rc = mdbx_env_cthr_toggle(my);
-              if (unlikely(rc != MDBX_SUCCESS))
-                goto done;
-              toggle = my->mc_head & 1;
-            }
-            mo = (MDBX_page *)(my->mc_wbuf[toggle] + my->mc_wlen[toggle]);
-            memcpy(mo, omp, my->mc_env->me_psize);
-            mo->mp_pgno = my->mc_next_pgno;
-            my->mc_next_pgno += omp->mp_pages;
-            my->mc_wlen[toggle] += my->mc_env->me_psize;
-            if (omp->mp_pages > 1) {
-              my->mc_olen[toggle] = pgno2bytes(my->mc_env, omp->mp_pages - 1);
-              my->mc_over[toggle] = (uint8_t *)omp + my->mc_env->me_psize;
-              rc = mdbx_env_cthr_toggle(my);
-              if (unlikely(rc != MDBX_SUCCESS))
-                goto done;
-              toggle = my->mc_head & 1;
-            }
-          } else if (node_flags(node) & F_SUBDATA) {
-            if (node_ds(node) != sizeof(MDBX_db)) {
-              rc = MDBX_CORRUPTED;
-              goto done;
-            }
-
-            /* Need writable leaf */
-            if (mp != leaf) {
-              couple.outer.mc_pg[couple.outer.mc_top] = leaf;
-              mdbx_page_copy(leaf, mp, my->mc_env->me_psize);
-              mp = leaf;
-              node = page_node(mp, i);
-            }
-
-            MDBX_db db;
-            memcpy(&db, node_data(node), sizeof(MDBX_db));
-            rc = mdbx_env_cwalk(my, &db.md_root, node_flags(node) & F_DUPDATA);
-            if (rc)
-              goto done;
-            memcpy(node_data(node), &db, sizeof(MDBX_db));
-          }
-        }
-      }
-    } else {
-      couple.outer.mc_ki[couple.outer.mc_top]++;
-      if (couple.outer.mc_ki[couple.outer.mc_top] < n) {
-      again:
-        rc = mdbx_page_get(
-            &couple.outer,
-            node_pgno(page_node(mp, couple.outer.mc_ki[couple.outer.mc_top])),
-            &mp, NULL, pp_txnid4chk(mp, my->mc_txn));
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto done;
-        couple.outer.mc_top++;
-        couple.outer.mc_snum++;
-        couple.outer.mc_ki[couple.outer.mc_top] = 0;
-        if (IS_BRANCH(mp)) {
-          /* Whenever we advance to a sibling branch page,
-           * we must proceed all the way down to its first leaf. */
-          mdbx_page_copy(couple.outer.mc_pg[couple.outer.mc_top], mp,
-                         my->mc_env->me_psize);
-          goto again;
-        } else
-          couple.outer.mc_pg[couple.outer.mc_top] = mp;
-        continue;
-      }
-    }
-    unsigned toggle = my->mc_head & 1;
-    if (my->mc_wlen[toggle] + my->mc_wlen[toggle] > MDBX_WBUF) {
-      rc = mdbx_env_cthr_toggle(my);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto done;
-      toggle = my->mc_head & 1;
-    }
-    mo = (MDBX_page *)(my->mc_wbuf[toggle] + my->mc_wlen[toggle]);
-    mdbx_page_copy(mo, mp, my->mc_env->me_psize);
-    mo->mp_pgno = my->mc_next_pgno++;
-    my->mc_wlen[toggle] += my->mc_env->me_psize;
-    if (couple.outer.mc_top) {
-      /* Update parent if there is one */
-      node_set_pgno(page_node(couple.outer.mc_pg[couple.outer.mc_top - 1],
-                              couple.outer.mc_ki[couple.outer.mc_top - 1]),
-                    mo->mp_pgno);
-      mdbx_cursor_pop(&couple.outer);
-    } else {
-      /* Otherwise we're done */
-      *pg = mo->mp_pgno;
-      break;
-    }
-  }
-done:
-  mdbx_free(buf);
-  return rc;
-}
-
-static __cold void compact_fixup_meta(MDBX_env *env, MDBX_meta *meta) {
-  /* Calculate filesize taking in account shrink/growing thresholds */
-  if (meta->mm_geo.next != meta->mm_geo.now) {
-    meta->mm_geo.now = meta->mm_geo.next;
-    const pgno_t aligner =
-        meta->mm_geo.grow ? meta->mm_geo.grow : meta->mm_geo.shrink;
-    if (aligner) {
-      const pgno_t aligned = pgno_align2os_pgno(
-          env, meta->mm_geo.next + aligner - meta->mm_geo.next % aligner);
-      meta->mm_geo.now = aligned;
-    }
-  }
-
-  if (meta->mm_geo.now < meta->mm_geo.lower)
-    meta->mm_geo.now = meta->mm_geo.lower;
-  if (meta->mm_geo.now > meta->mm_geo.upper)
-    meta->mm_geo.now = meta->mm_geo.upper;
-
-  /* Update signature */
-  assert(meta->mm_geo.now >= meta->mm_geo.next);
-  unaligned_poke_u64(4, meta->mm_datasync_sign, mdbx_meta_sign(meta));
-}
-
-/* Make resizeable */
-static __cold void make_sizeable(MDBX_meta *meta) {
-  meta->mm_geo.lower = MIN_PAGENO;
-  if (meta->mm_geo.grow == 0) {
-    const size_t step = 1 + (meta->mm_geo.upper - meta->mm_geo.lower) / 42;
-    meta->mm_geo.grow = (step < UINT16_MAX) ? (uint16_t)step : UINT16_MAX;
-  }
-  if (meta->mm_geo.shrink == 0) {
-    const size_t step = meta->mm_geo.grow + meta->mm_geo.grow;
-    meta->mm_geo.shrink = (step < UINT16_MAX) ? (uint16_t)step : UINT16_MAX;
-  }
-}
-
-/* Copy environment with compaction. */
-static __cold int mdbx_env_compact(MDBX_env *env, MDBX_txn *read_txn,
-                                   mdbx_filehandle_t fd, uint8_t *buffer,
-                                   const bool dest_is_pipe, const int flags) {
-  const size_t meta_bytes = pgno2bytes(env, NUM_METAS);
-  uint8_t *const data_buffer =
-      buffer + ceil_powerof2(meta_bytes, env->me_os_psize);
-  MDBX_meta *const meta = mdbx_init_metas(env, buffer);
-  mdbx_meta_set_txnid(env, meta, read_txn->mt_txnid);
-
-  if (flags & MDBX_CP_FORCE_DYNAMIC_SIZE)
-    make_sizeable(meta);
-
-  /* copy canary sequences if present */
-  if (read_txn->mt_canary.v) {
-    meta->mm_canary = read_txn->mt_canary;
-    meta->mm_canary.v = mdbx_meta_txnid_stable(env, meta);
-  }
-
-  /* Set metapage 1 with current main DB */
-  pgno_t new_root, root = read_txn->mt_dbs[MAIN_DBI].md_root;
-  if ((new_root = root) == P_INVALID) {
-    /* When the DB is empty, handle it specially to
-     * fix any breakage like page leaks from ITS#8174. */
-    meta->mm_dbs[MAIN_DBI].md_flags = read_txn->mt_dbs[MAIN_DBI].md_flags;
-    compact_fixup_meta(env, meta);
-    if (dest_is_pipe) {
-      int rc = mdbx_write(fd, buffer, meta_bytes);
-      if (rc != MDBX_SUCCESS)
-        return rc;
-    }
-  } else {
-    /* Count free pages + GC pages.  Subtract from last_pg
-     * to find the new last_pg, which also becomes the new root. */
-    pgno_t freecount = 0;
-    MDBX_cursor_couple couple;
-    MDBX_val key, data;
-
-    int rc = mdbx_cursor_init(&couple.outer, read_txn, FREE_DBI);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    while ((rc = mdbx_cursor_get(&couple.outer, &key, &data, MDBX_NEXT)) == 0)
-      freecount += *(pgno_t *)data.iov_base;
-    if (unlikely(rc != MDBX_NOTFOUND))
-      return rc;
-
-    freecount += read_txn->mt_dbs[FREE_DBI].md_branch_pages +
-                 read_txn->mt_dbs[FREE_DBI].md_leaf_pages +
-                 read_txn->mt_dbs[FREE_DBI].md_overflow_pages;
-
-    new_root = read_txn->mt_next_pgno - 1 - freecount;
-    meta->mm_geo.next = new_root + 1;
-    meta->mm_dbs[MAIN_DBI] = read_txn->mt_dbs[MAIN_DBI];
-    meta->mm_dbs[MAIN_DBI].md_root = new_root;
-
-    mdbx_copy ctx;
-    memset(&ctx, 0, sizeof(ctx));
-    rc = mdbx_condpair_init(&ctx.mc_condpair);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-
-    memset(data_buffer, 0, MDBX_WBUF * 2);
-    ctx.mc_wbuf[0] = data_buffer;
-    ctx.mc_wbuf[1] = data_buffer + MDBX_WBUF;
-    ctx.mc_next_pgno = NUM_METAS;
-    ctx.mc_env = env;
-    ctx.mc_fd = fd;
-    ctx.mc_txn = read_txn;
-
-    mdbx_thread_t thread;
-    int thread_err = mdbx_thread_create(&thread, mdbx_env_copythr, &ctx);
-    if (likely(thread_err == MDBX_SUCCESS)) {
-      if (dest_is_pipe) {
-        compact_fixup_meta(env, meta);
-        rc = mdbx_write(fd, buffer, meta_bytes);
-      }
-      if (rc == MDBX_SUCCESS)
-        rc = mdbx_env_cwalk(&ctx, &root, 0);
-      mdbx_env_cthr_toggle(&ctx);
-      mdbx_env_cthr_toggle(&ctx);
-      thread_err = mdbx_thread_join(thread);
-      mdbx_assert(env, (ctx.mc_tail == ctx.mc_head &&
-                        ctx.mc_wlen[ctx.mc_head & 1] == 0) ||
-                           ctx.mc_error);
-      mdbx_condpair_destroy(&ctx.mc_condpair);
-    }
-    if (unlikely(thread_err != MDBX_SUCCESS))
-      return thread_err;
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    if (unlikely(ctx.mc_error != MDBX_SUCCESS))
-      return ctx.mc_error;
-
-    if (dest_is_pipe) {
-      if (root != new_root) {
-        mdbx_error("post-compactification root %" PRIaPGNO
-                   " NE expected %" PRIaPGNO
-                   " (source DB corrupted or has a page leak(s))",
-                   root, new_root);
-        return MDBX_CORRUPTED; /* page leak or corrupt DB */
-      }
-    } else {
-      if (root > new_root) {
-        mdbx_error("post-compactification root %" PRIaPGNO
-                   " GT expected %" PRIaPGNO " (source DB corrupted)",
-                   root, new_root);
-        return MDBX_CORRUPTED; /* page leak or corrupt DB */
-      }
-      if (root < new_root) {
-        mdbx_warning("post-compactification root %" PRIaPGNO
-                     " LT expected %" PRIaPGNO " (page leak(s) in source DB)",
-                     root, new_root);
-        /* fixup meta */
-        meta->mm_dbs[MAIN_DBI].md_root = root;
-        meta->mm_geo.next = root + 1;
-      }
-      compact_fixup_meta(env, meta);
-    }
-  }
-
-  /* Extend file if required */
-  if (meta->mm_geo.now != meta->mm_geo.next) {
-    const size_t whole_size = pgno2bytes(env, meta->mm_geo.now);
-    if (!dest_is_pipe)
-      return mdbx_ftruncate(fd, whole_size);
-
-    const size_t used_size = pgno2bytes(env, meta->mm_geo.next);
-    memset(data_buffer, 0, MDBX_WBUF);
-    for (size_t offset = used_size; offset < whole_size;) {
-      const size_t chunk =
-          (MDBX_WBUF < whole_size - offset) ? MDBX_WBUF : whole_size - offset;
-      /* copy to avoid EFAULT in case swapped-out */
-      int rc = mdbx_write(fd, data_buffer, chunk);
-      if (unlikely(rc != MDBX_SUCCESS))
-        return rc;
-      offset += chunk;
-    }
-  }
-  return MDBX_SUCCESS;
-}
-
-/* Copy environment as-is. */
-static __cold int mdbx_env_copy_asis(MDBX_env *env, MDBX_txn *read_txn,
-                                     mdbx_filehandle_t fd, uint8_t *buffer,
-                                     const bool dest_is_pipe, const int flags) {
-  /* We must start the actual read txn after blocking writers */
-  int rc = mdbx_txn_end(read_txn, MDBX_END_RESET_TMP);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  /* Temporarily block writers until we snapshot the meta pages */
-  rc = mdbx_txn_lock(env, false);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  rc = mdbx_txn_renew0(read_txn, MDBX_TXN_RDONLY);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    mdbx_txn_unlock(env);
-    return rc;
-  }
-
-  mdbx_jitter4testing(false);
-  const size_t meta_bytes = pgno2bytes(env, NUM_METAS);
-  /* Make a snapshot of meta-pages,
-   * but writing ones after the data was flushed */
-  memcpy(buffer, env->me_map, meta_bytes);
-  MDBX_meta *const headcopy = /* LY: get pointer to the snapshot copy */
-      (MDBX_meta *)(buffer + ((uint8_t *)mdbx_meta_head(env) - env->me_map));
-  mdbx_txn_unlock(env);
-
-  if (flags & MDBX_CP_FORCE_DYNAMIC_SIZE)
-    make_sizeable(headcopy);
-  /* Update signature to steady */
-  unaligned_poke_u64(4, headcopy->mm_datasync_sign, mdbx_meta_sign(headcopy));
-
-  /* Copy the data */
-  const size_t whole_size = pgno_align2os_bytes(env, read_txn->mt_end_pgno);
-  const size_t used_size = pgno2bytes(env, read_txn->mt_next_pgno);
-  mdbx_jitter4testing(false);
-
-  if (dest_is_pipe)
-    rc = mdbx_write(fd, buffer, meta_bytes);
-
-  uint8_t *const data_buffer =
-      buffer + ceil_powerof2(meta_bytes, env->me_os_psize);
-  for (size_t offset = meta_bytes; rc == MDBX_SUCCESS && offset < used_size;) {
-#if MDBX_USE_SENDFILE
-    static bool sendfile_unavailable;
-    if (dest_is_pipe && likely(!sendfile_unavailable)) {
-      off_t in_offset = offset;
-      const ssize_t written =
-          sendfile(fd, env->me_lazy_fd, &in_offset, used_size - offset);
-      if (likely(written > 0)) {
-        offset = in_offset;
-        continue;
-      }
-      rc = MDBX_ENODATA;
-      if (written == 0 || ignore_enosys(rc = errno) != MDBX_RESULT_TRUE)
-        break;
-      sendfile_unavailable = true;
-    }
-#endif /* MDBX_USE_SENDFILE */
-
-#if MDBX_USE_COPYFILERANGE
-    static bool copyfilerange_unavailable;
-    if (!dest_is_pipe && likely(!copyfilerange_unavailable)) {
-      off_t in_offset = offset, out_offset = offset;
-      ssize_t bytes_copied = copy_file_range(
-          env->me_lazy_fd, &in_offset, fd, &out_offset, used_size - offset, 0);
-      if (likely(bytes_copied > 0)) {
-        offset = in_offset;
-        continue;
-      }
-      rc = MDBX_ENODATA;
-      if (bytes_copied == 0 || ignore_enosys(rc = errno) != MDBX_RESULT_TRUE)
-        break;
-      copyfilerange_unavailable = true;
-    }
-#endif /* MDBX_USE_COPYFILERANGE */
-
-    /* fallback to portable */
-    const size_t chunk =
-        (MDBX_WBUF < used_size - offset) ? MDBX_WBUF : used_size - offset;
-    /* copy to avoid EFAULT in case swapped-out */
-    memcpy(data_buffer, env->me_map + offset, chunk);
-    rc = mdbx_write(fd, data_buffer, chunk);
-    offset += chunk;
-  }
-
-  /* Extend file if required */
-  if (likely(rc == MDBX_SUCCESS) && whole_size != used_size) {
-    if (!dest_is_pipe)
-      rc = mdbx_ftruncate(fd, whole_size);
-    else {
-      memset(data_buffer, 0, MDBX_WBUF);
-      for (size_t offset = used_size;
-           rc == MDBX_SUCCESS && offset < whole_size;) {
-        const size_t chunk =
-            (MDBX_WBUF < whole_size - offset) ? MDBX_WBUF : whole_size - offset;
-        /* copy to avoid EFAULT in case swapped-out */
-        rc = mdbx_write(fd, data_buffer, chunk);
-        offset += chunk;
-      }
-    }
-  }
-
-  return rc;
-}
-
-__cold int mdbx_env_copy2fd(MDBX_env *env, mdbx_filehandle_t fd,
-                            unsigned flags) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  const int dest_is_pipe = mdbx_is_pipe(fd);
-  if (MDBX_IS_ERROR(dest_is_pipe))
-    return dest_is_pipe;
-
-  if (!dest_is_pipe) {
-    rc = mdbx_fseek(fd, 0);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  const size_t buffer_size =
-      pgno_align2os_bytes(env, NUM_METAS) +
-      ceil_powerof2(((flags & MDBX_CP_COMPACT) ? MDBX_WBUF * 2 : MDBX_WBUF),
-                    env->me_os_psize);
-
-  uint8_t *buffer = NULL;
-  rc = mdbx_memalign_alloc(env->me_os_psize, buffer_size, (void **)&buffer);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  MDBX_txn *read_txn = NULL;
-  /* Do the lock/unlock of the reader mutex before starting the
-   * write txn. Otherwise other read txns could block writers. */
-  rc = mdbx_txn_begin(env, NULL, MDBX_TXN_RDONLY, &read_txn);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    mdbx_memalign_free(buffer);
-    return rc;
-  }
-
-  if (!dest_is_pipe) {
-    /* Firstly write a stub to meta-pages.
-     * Now we sure to incomplete copy will not be used. */
-    memset(buffer, -1, pgno2bytes(env, NUM_METAS));
-    rc = mdbx_write(fd, buffer, pgno2bytes(env, NUM_METAS));
-  }
-
-  if (likely(rc == MDBX_SUCCESS)) {
-    memset(buffer, 0, pgno2bytes(env, NUM_METAS));
-    rc = ((flags & MDBX_CP_COMPACT) ? mdbx_env_compact : mdbx_env_copy_asis)(
-        env, read_txn, fd, buffer, dest_is_pipe, flags);
-  }
-  mdbx_txn_abort(read_txn);
-
-  if (!dest_is_pipe) {
-    if (likely(rc == MDBX_SUCCESS))
-      rc = mdbx_fsync(fd, MDBX_SYNC_DATA | MDBX_SYNC_SIZE);
-
-    /* Write actual meta */
-    if (likely(rc == MDBX_SUCCESS))
-      rc = mdbx_pwrite(fd, buffer, pgno2bytes(env, NUM_METAS), 0);
-
-    if (likely(rc == MDBX_SUCCESS))
-      rc = mdbx_fsync(fd, MDBX_SYNC_DATA | MDBX_SYNC_IODQ);
-  }
-
-  mdbx_memalign_free(buffer);
-  return rc;
-}
-
-__cold int mdbx_env_copy(MDBX_env *env, const char *dest_path,
-                         MDBX_copy_flags_t flags) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!dest_path))
-    return MDBX_EINVAL;
-
-  /* The destination path must exist, but the destination file must not.
-   * We don't want the OS to cache the writes, since the source data is
-   * already in the OS cache. */
-  mdbx_filehandle_t newfd;
-  rc = mdbx_openfile(MDBX_OPEN_COPY, env, dest_path, &newfd,
-#if defined(_WIN32) || defined(_WIN64)
-                     (mdbx_mode_t)-1
-#else
-                     S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP
-#endif
-  );
-
-  if (rc == MDBX_SUCCESS) {
-#if defined(_WIN32) || defined(_WIN64)
-    OVERLAPPED ov;
-    memset(&ov, 0, sizeof(ov));
-    if (!LockFileEx(newfd, LOCKFILE_EXCLUSIVE_LOCK | LOCKFILE_FAIL_IMMEDIATELY,
-                    0, 0, INT32_MAX, &ov))
-      rc = GetLastError();
-#else
-    struct flock lock_op;
-    memset(&lock_op, 0, sizeof(lock_op));
-    lock_op.l_type = F_WRLCK;
-    lock_op.l_whence = SEEK_SET;
-    lock_op.l_start = 0;
-    lock_op.l_len =
-        (sizeof(lock_op.l_len) > 4 ? INT64_MAX : INT32_MAX) & ~(size_t)0xffff;
-    if (fcntl(newfd, F_SETLK, &lock_op)
-#if (defined(__linux__) || defined(__gnu_linux__)) && defined(LOCK_EX) &&      \
-    (!defined(__ANDROID_API__) || __ANDROID_API__ >= 24)
-        || flock(newfd, LOCK_EX | LOCK_NB)
-#endif /* Linux */
-    )
-      rc = errno;
-#endif /* Windows / POSIX */
-  }
-
-  if (rc == MDBX_SUCCESS)
-    rc = mdbx_env_copy2fd(env, newfd, flags);
-
-  if (newfd != INVALID_HANDLE_VALUE) {
-    int err = mdbx_closefile(newfd);
-    if (rc == MDBX_SUCCESS && err != rc)
-      rc = err;
-    if (rc != MDBX_SUCCESS)
-      (void)mdbx_removefile(dest_path);
-  }
-
-  return rc;
-}
-
-/******************************************************************************/
-
-__cold int mdbx_env_set_flags(MDBX_env *env, MDBX_env_flags_t flags,
-                              bool onoff) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(flags & ~ENV_CHANGEABLE_FLAGS))
-    return MDBX_EPERM;
-
-  if (unlikely(env->me_flags & MDBX_RDONLY))
-    return MDBX_EACCESS;
-
-  if (unlikely(env->me_txn0->mt_owner == mdbx_thread_self()))
-    return MDBX_BUSY;
-
-  rc = mdbx_txn_lock(env, false);
-  if (unlikely(rc))
-    return rc;
-
-  if (onoff)
-    env->me_flags = merge_sync_flags(env->me_flags, flags);
-  else
-    env->me_flags &= ~flags;
-
-  mdbx_txn_unlock(env);
-  return MDBX_SUCCESS;
-}
-
-__cold int mdbx_env_get_flags(const MDBX_env *env, unsigned *arg) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!arg))
-    return MDBX_EINVAL;
-
-  *arg = env->me_flags & ENV_USABLE_FLAGS;
-  return MDBX_SUCCESS;
-}
-
-__cold int mdbx_env_set_userctx(MDBX_env *env, void *ctx) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  env->me_userctx = ctx;
-  return MDBX_SUCCESS;
-}
-
-void *__cold mdbx_env_get_userctx(const MDBX_env *env) {
-  return env ? env->me_userctx : NULL;
-}
-
-__cold int mdbx_env_set_assert(MDBX_env *env, MDBX_assert_func *func) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-#if MDBX_DEBUG
-  env->me_assert_func = func;
-  return MDBX_SUCCESS;
-#else
-  (void)func;
-  return MDBX_ENOSYS;
-#endif
-}
-
-__cold int mdbx_env_get_path(const MDBX_env *env, const char **arg) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!arg))
-    return MDBX_EINVAL;
-
-  *arg = env->me_pathname;
-  return MDBX_SUCCESS;
-}
-
-__cold int mdbx_env_get_fd(const MDBX_env *env, mdbx_filehandle_t *arg) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!arg))
-    return MDBX_EINVAL;
-
-  *arg = env->me_lazy_fd;
-  return MDBX_SUCCESS;
-}
-
-/* Common code for mdbx_dbi_stat() and mdbx_env_stat().
- * [in] env the environment to operate in.
- * [in] db the MDBX_db record containing the stats to return.
- * [out] arg the address of an MDBX_stat structure to receive the stats.
- * Returns 0, this function always succeeds. */
-static void mdbx_stat0(const MDBX_env *env, const MDBX_db *db, MDBX_stat *dest,
-                       size_t bytes) {
-  dest->ms_psize = env->me_psize;
-  dest->ms_depth = db->md_depth;
-  dest->ms_branch_pages = db->md_branch_pages;
-  dest->ms_leaf_pages = db->md_leaf_pages;
-  dest->ms_overflow_pages = db->md_overflow_pages;
-  dest->ms_entries = db->md_entries;
-  if (likely(bytes >=
-             offsetof(MDBX_stat, ms_mod_txnid) + sizeof(dest->ms_mod_txnid)))
-    dest->ms_mod_txnid = db->md_mod_txnid;
-}
-
-__cold int mdbx_env_stat(const MDBX_env *env, MDBX_stat *stat, size_t bytes) {
-  return __inline_mdbx_env_stat(env, stat, bytes);
-}
-
-__cold int mdbx_env_stat_ex(const MDBX_env *env, const MDBX_txn *txn,
-                            MDBX_stat *dest, size_t bytes) {
-  if (unlikely((env == NULL && txn == NULL) || dest == NULL))
-    return MDBX_EINVAL;
-
-  if (txn) {
-    int err = check_txn(txn, MDBX_TXN_BLOCKED);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-  }
-  if (env) {
-    int err = check_env(env);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-    if (txn && unlikely(txn->mt_env != env))
-      return MDBX_EINVAL;
-  }
-
-  const size_t size_before_modtxnid = offsetof(MDBX_stat, ms_mod_txnid);
-  if (unlikely(bytes != sizeof(MDBX_stat)) && bytes != size_before_modtxnid)
-    return MDBX_EINVAL;
-
-  if (txn) {
-    mdbx_stat0(txn->mt_env, &txn->mt_dbs[MAIN_DBI], dest, bytes);
-    return MDBX_SUCCESS;
-  }
-
-  while (1) {
-    const MDBX_meta *const recent_meta = mdbx_meta_head(env);
-    const txnid_t txnid = mdbx_meta_txnid_fluid(env, recent_meta);
-    mdbx_stat0(env, &recent_meta->mm_dbs[MAIN_DBI], dest, bytes);
-    mdbx_compiler_barrier();
-    if (likely(txnid == mdbx_meta_txnid_fluid(env, recent_meta) &&
-               recent_meta == mdbx_meta_head(env)))
-      return MDBX_SUCCESS;
-  }
-}
-
-__cold int mdbx_dbi_dupsort_depthmask(MDBX_txn *txn, MDBX_dbi dbi,
-                                      uint32_t *mask) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mask))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_VALID)))
-    return MDBX_BAD_DBI;
-
-  MDBX_cursor_couple cx;
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  if ((cx.outer.mc_db->md_flags & MDBX_DUPSORT) == 0)
-    return MDBX_RESULT_TRUE;
-
-  MDBX_val key, data;
-  rc = mdbx_cursor_first(&cx.outer, &key, &data);
-  *mask = 0;
-  while (rc == MDBX_SUCCESS) {
-    const MDBX_node *node = page_node(cx.outer.mc_pg[cx.outer.mc_top],
-                                      cx.outer.mc_ki[cx.outer.mc_top]);
-    const MDBX_db *db = node_data(node);
-    const unsigned flags = node_flags(node);
-    switch (flags) {
-    case F_BIGDATA:
-    case 0:
-      /* single-value entry, deep = 0 */
-      *mask |= 1 << 0;
-      break;
-    case F_DUPDATA:
-      /* single sub-page, deep = 1 */
-      *mask |= 1 << 1;
-      break;
-    case F_DUPDATA | F_SUBDATA:
-      /* sub-tree */
-      *mask |= 1 << unaligned_peek_u16(1, &db->md_depth);
-      break;
-    default:
-      mdbx_error("wrong node-flags %u", flags);
-      return MDBX_CORRUPTED;
-    }
-    rc = mdbx_cursor_next(&cx.outer, &key, &data, MDBX_NEXT_NODUP);
-  }
-
-  return (rc == MDBX_NOTFOUND) ? MDBX_SUCCESS : rc;
-}
-
-__cold int mdbx_env_info(const MDBX_env *env, MDBX_envinfo *info,
-                         size_t bytes) {
-  return __inline_mdbx_env_info(env, info, bytes);
-}
-
-__cold int mdbx_env_info_ex(const MDBX_env *env, const MDBX_txn *txn,
-                            MDBX_envinfo *arg, size_t bytes) {
-  if (unlikely((env == NULL && txn == NULL) || arg == NULL))
-    return MDBX_EINVAL;
-
-  if (txn) {
-    int err = check_txn(txn, MDBX_TXN_BLOCKED);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-  }
-  if (env) {
-    int err = check_env(env);
-    if (unlikely(err != MDBX_SUCCESS))
-      return err;
-    if (txn && unlikely(txn->mt_env != env))
-      return MDBX_EINVAL;
-  } else {
-    env = txn->mt_env;
-  }
-
-  const size_t size_before_bootid = offsetof(MDBX_envinfo, mi_bootid);
-  if (unlikely(bytes != sizeof(MDBX_envinfo)) && bytes != size_before_bootid)
-    return MDBX_EINVAL;
-
-  const MDBX_meta *const meta0 = METAPAGE(env, 0);
-  const MDBX_meta *const meta1 = METAPAGE(env, 1);
-  const MDBX_meta *const meta2 = METAPAGE(env, 2);
-  pgno_t unsynced_pages;
-  while (1) {
-    if (unlikely(env->me_flags & MDBX_FATAL_ERROR))
-      return MDBX_PANIC;
-
-    const MDBX_meta *const recent_meta = mdbx_meta_head(env);
-    arg->mi_recent_txnid = mdbx_meta_txnid_fluid(env, recent_meta);
-    arg->mi_meta0_txnid = mdbx_meta_txnid_fluid(env, meta0);
-    arg->mi_meta0_sign = unaligned_peek_u64(4, meta0->mm_datasync_sign);
-    arg->mi_meta1_txnid = mdbx_meta_txnid_fluid(env, meta1);
-    arg->mi_meta1_sign = unaligned_peek_u64(4, meta1->mm_datasync_sign);
-    arg->mi_meta2_txnid = mdbx_meta_txnid_fluid(env, meta2);
-    arg->mi_meta2_sign = unaligned_peek_u64(4, meta2->mm_datasync_sign);
-    if (likely(bytes > size_before_bootid)) {
-      memcpy(&arg->mi_bootid.meta0, &meta0->mm_bootid, 16);
-      memcpy(&arg->mi_bootid.meta1, &meta1->mm_bootid, 16);
-      memcpy(&arg->mi_bootid.meta2, &meta2->mm_bootid, 16);
-    }
-
-    const MDBX_meta *txn_meta = recent_meta;
-    arg->mi_last_pgno = txn_meta->mm_geo.next - 1;
-    arg->mi_geo.current = pgno2bytes(env, txn_meta->mm_geo.now);
-    if (txn) {
-      arg->mi_last_pgno = txn->mt_next_pgno - 1;
-      arg->mi_geo.current = pgno2bytes(env, txn->mt_end_pgno);
-
-      const txnid_t wanna_meta_txnid = (txn->mt_flags & MDBX_TXN_RDONLY)
-                                           ? txn->mt_txnid
-                                           : txn->mt_txnid - MDBX_TXNID_STEP;
-      txn_meta = (arg->mi_meta0_txnid == wanna_meta_txnid) ? meta0 : txn_meta;
-      txn_meta = (arg->mi_meta1_txnid == wanna_meta_txnid) ? meta1 : txn_meta;
-      txn_meta = (arg->mi_meta2_txnid == wanna_meta_txnid) ? meta2 : txn_meta;
-    }
-    arg->mi_geo.lower = pgno2bytes(env, txn_meta->mm_geo.lower);
-    arg->mi_geo.upper = pgno2bytes(env, txn_meta->mm_geo.upper);
-    arg->mi_geo.shrink = pgno2bytes(env, txn_meta->mm_geo.shrink);
-    arg->mi_geo.grow = pgno2bytes(env, txn_meta->mm_geo.grow);
-    unsynced_pages = atomic_load32(env->me_unsynced_pages, mo_Relaxed) +
-                     (atomic_load32(env->me_meta_sync_txnid, mo_Relaxed) !=
-                      (uint32_t)arg->mi_last_pgno);
-
-    arg->mi_mapsize = env->me_dxb_mmap.limit;
-    mdbx_compiler_barrier();
-    if (likely(arg->mi_meta0_txnid == mdbx_meta_txnid_fluid(env, meta0) &&
-               arg->mi_meta0_sign ==
-                   unaligned_peek_u64(4, meta0->mm_datasync_sign) &&
-               arg->mi_meta1_txnid == mdbx_meta_txnid_fluid(env, meta1) &&
-               arg->mi_meta1_sign ==
-                   unaligned_peek_u64(4, meta1->mm_datasync_sign) &&
-               arg->mi_meta2_txnid == mdbx_meta_txnid_fluid(env, meta2) &&
-               arg->mi_meta2_sign ==
-                   unaligned_peek_u64(4, meta2->mm_datasync_sign) &&
-               recent_meta == mdbx_meta_head(env) &&
-               arg->mi_recent_txnid == mdbx_meta_txnid_fluid(env, recent_meta)))
-      break;
-  }
-
-  arg->mi_maxreaders = env->me_maxreaders;
-  arg->mi_numreaders =
-      env->me_lck ? atomic_load32(&env->me_lck->mti_numreaders, mo_Relaxed)
-                  : INT32_MAX;
-  arg->mi_dxb_pagesize = env->me_psize;
-  arg->mi_sys_pagesize = env->me_os_psize;
-
-  const MDBX_lockinfo *const lck = env->me_lck;
-  if (likely(bytes > size_before_bootid)) {
-    arg->mi_unsync_volume = pgno2bytes(env, unsynced_pages);
-    const uint64_t monotime_now = mdbx_osal_monotime();
-    arg->mi_since_sync_seconds16dot16 = mdbx_osal_monotime_to_16dot16(
-        monotime_now - atomic_load64(env->me_sync_timestamp, mo_Relaxed));
-    arg->mi_since_reader_check_seconds16dot16 =
-        lck ? mdbx_osal_monotime_to_16dot16(
-                  monotime_now -
-                  atomic_load64(&lck->mti_reader_check_timestamp, mo_Relaxed))
-            : 0;
-    arg->mi_autosync_threshold =
-        pgno2bytes(env, atomic_load32(env->me_autosync_threshold, mo_Relaxed));
-    arg->mi_autosync_period_seconds16dot16 = mdbx_osal_monotime_to_16dot16(
-        atomic_load64(env->me_autosync_period, mo_Relaxed));
-    arg->mi_bootid.current.x = bootid.x;
-    arg->mi_bootid.current.y = bootid.y;
-    arg->mi_mode = lck ? lck->mti_envmode.weak : env->me_flags;
-  }
-
-  arg->mi_self_latter_reader_txnid = arg->mi_latter_reader_txnid = 0;
-  if (lck) {
-    arg->mi_self_latter_reader_txnid = arg->mi_latter_reader_txnid =
-        arg->mi_recent_txnid;
-    for (unsigned i = 0; i < arg->mi_numreaders; ++i) {
-      const uint32_t pid =
-          atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease);
-      if (pid) {
-        const txnid_t txnid = safe64_read(&lck->mti_readers[i].mr_txnid);
-        if (arg->mi_latter_reader_txnid > txnid)
-          arg->mi_latter_reader_txnid = txnid;
-        if (pid == env->me_pid && arg->mi_self_latter_reader_txnid > txnid)
-          arg->mi_self_latter_reader_txnid = txnid;
-      }
-    }
-  }
-
-  return MDBX_SUCCESS;
-}
-
-static __inline MDBX_cmp_func *get_default_keycmp(unsigned flags) {
-  return (flags & MDBX_REVERSEKEY)
-             ? cmp_reverse
-             : (flags & MDBX_INTEGERKEY) ? cmp_int_align2 : cmp_lexical;
-}
-
-static __inline MDBX_cmp_func *get_default_datacmp(unsigned flags) {
-  return !(flags & MDBX_DUPSORT)
-             ? cmp_lenfast
-             : ((flags & MDBX_INTEGERDUP)
-                    ? cmp_int_unaligned
-                    : ((flags & MDBX_REVERSEDUP) ? cmp_reverse : cmp_lexical));
-}
-
-static int mdbx_dbi_bind(MDBX_txn *txn, const MDBX_dbi dbi, unsigned user_flags,
-                         MDBX_cmp_func *keycmp, MDBX_cmp_func *datacmp) {
-  /* LY: so, accepting only three cases for the table's flags:
-   * 1) user_flags and both comparators are zero
-   *    = assume that a by-default mode/flags is requested for reading;
-   * 2) user_flags exactly the same
-   *    = assume that the target mode/flags are requested properly;
-   * 3) user_flags differs, but table is empty and MDBX_CREATE is provided
-   *    = assume that a properly create request with custom flags;
-   */
-  if ((user_flags ^ txn->mt_dbs[dbi].md_flags) & DB_PERSISTENT_FLAGS) {
-    /* flags are differs, check other conditions */
-    if ((!user_flags && (!keycmp || keycmp == txn->mt_dbxs[dbi].md_cmp) &&
-         (!datacmp || datacmp == txn->mt_dbxs[dbi].md_dcmp)) ||
-        user_flags == MDBX_ACCEDE) {
-      /* no comparators were provided and flags are zero,
-       * seems that is case #1 above */
-      user_flags = txn->mt_dbs[dbi].md_flags;
-    } else if ((user_flags & MDBX_CREATE) && txn->mt_dbs[dbi].md_entries == 0) {
-      if (txn->mt_flags & MDBX_TXN_RDONLY)
-        return /* FIXME: return extended info */ MDBX_EACCESS;
-      /* make sure flags changes get committed */
-      txn->mt_dbs[dbi].md_flags = user_flags & DB_PERSISTENT_FLAGS;
-      txn->mt_flags |= MDBX_TXN_DIRTY;
-    } else {
-      return /* FIXME: return extended info */ MDBX_INCOMPATIBLE;
-    }
-  }
-
-  if (!keycmp)
-    keycmp = txn->mt_dbxs[dbi].md_cmp ? txn->mt_dbxs[dbi].md_cmp
-                                      : get_default_keycmp(user_flags);
-  if (txn->mt_dbxs[dbi].md_cmp != keycmp) {
-    if (txn->mt_dbxs[dbi].md_cmp)
-      return MDBX_EINVAL;
-    txn->mt_dbxs[dbi].md_cmp = keycmp;
-  }
-
-  if (!datacmp)
-    datacmp = txn->mt_dbxs[dbi].md_dcmp ? txn->mt_dbxs[dbi].md_dcmp
-                                        : get_default_datacmp(user_flags);
-  if (txn->mt_dbxs[dbi].md_dcmp != datacmp) {
-    if (txn->mt_dbxs[dbi].md_dcmp)
-      return MDBX_EINVAL;
-    txn->mt_dbxs[dbi].md_dcmp = datacmp;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-static int dbi_open(MDBX_txn *txn, const char *table_name, unsigned user_flags,
-                    MDBX_dbi *dbi, MDBX_cmp_func *keycmp,
-                    MDBX_cmp_func *datacmp) {
-  int rc = MDBX_EINVAL;
-  if (unlikely(!dbi))
-    return rc;
-
-  if (unlikely((user_flags & ~DB_USABLE_FLAGS) != 0)) {
-  early_bailout:
-    *dbi = 0;
-    return rc;
-  }
-
-  rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto early_bailout;
-
-  switch (user_flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED | MDBX_DUPSORT |
-                        MDBX_REVERSEDUP | MDBX_ACCEDE)) {
-  case MDBX_ACCEDE:
-    if ((user_flags & MDBX_CREATE) == 0)
-      break;
-    __fallthrough /* fall through */;
-  default:
-    rc = MDBX_EINVAL;
-    goto early_bailout;
-
-  case MDBX_DUPSORT:
-  case MDBX_DUPSORT | MDBX_REVERSEDUP:
-  case MDBX_DUPSORT | MDBX_DUPFIXED:
-  case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_REVERSEDUP:
-  case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP:
-  case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP:
-  case 0:
-    break;
-  }
-
-  /* main table? */
-  if (!table_name) {
-    rc = mdbx_dbi_bind(txn, MAIN_DBI, user_flags, keycmp, datacmp);
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto early_bailout;
-    *dbi = MAIN_DBI;
-    return rc;
-  }
-
-  if (txn->mt_dbxs[MAIN_DBI].md_cmp == NULL) {
-    txn->mt_dbxs[MAIN_DBI].md_cmp =
-        get_default_keycmp(txn->mt_dbs[MAIN_DBI].md_flags);
-    txn->mt_dbxs[MAIN_DBI].md_dcmp =
-        get_default_datacmp(txn->mt_dbs[MAIN_DBI].md_flags);
-  }
-
-  /* Is the DB already open? */
-  size_t len = strlen(table_name);
-  MDBX_dbi scan, slot;
-  for (slot = scan = txn->mt_numdbs; --scan >= CORE_DBS;) {
-    if (!txn->mt_dbxs[scan].md_name.iov_len) {
-      /* Remember this free slot */
-      slot = scan;
-      continue;
-    }
-    if (len == txn->mt_dbxs[scan].md_name.iov_len &&
-        !strncmp(table_name, txn->mt_dbxs[scan].md_name.iov_base, len)) {
-      rc = mdbx_dbi_bind(txn, scan, user_flags, keycmp, datacmp);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto early_bailout;
-      *dbi = scan;
-      return rc;
-    }
-  }
-
-  /* Fail, if no free slot and max hit */
-  MDBX_env *env = txn->mt_env;
-  if (unlikely(slot >= env->me_maxdbs)) {
-    rc = MDBX_DBS_FULL;
-    goto early_bailout;
-  }
-
-  /* Cannot mix named table with some main-table flags */
-  if (unlikely(txn->mt_dbs[MAIN_DBI].md_flags &
-               (MDBX_DUPSORT | MDBX_INTEGERKEY))) {
-    rc = (user_flags & MDBX_CREATE) ? MDBX_INCOMPATIBLE : MDBX_NOTFOUND;
-    goto early_bailout;
-  }
-
-  /* Find the DB info */
-  int exact = 0;
-  MDBX_val key, data;
-  key.iov_len = len;
-  key.iov_base = (void *)table_name;
-  MDBX_cursor_couple couple;
-  rc = mdbx_cursor_init(&couple.outer, txn, MAIN_DBI);
-  if (unlikely(rc != MDBX_SUCCESS))
-    goto early_bailout;
-  rc = mdbx_cursor_set(&couple.outer, &key, &data, MDBX_SET, &exact);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (rc != MDBX_NOTFOUND || !(user_flags & MDBX_CREATE))
-      goto early_bailout;
-  } else {
-    /* make sure this is actually a table */
-    MDBX_node *node = page_node(couple.outer.mc_pg[couple.outer.mc_top],
-                                couple.outer.mc_ki[couple.outer.mc_top]);
-    if (unlikely((node_flags(node) & (F_DUPDATA | F_SUBDATA)) != F_SUBDATA)) {
-      rc = MDBX_INCOMPATIBLE;
-      goto early_bailout;
-    }
-    if (unlikely(data.iov_len != sizeof(MDBX_db))) {
-      rc = MDBX_CORRUPTED;
-      goto early_bailout;
-    }
-  }
-
-  if (rc != MDBX_SUCCESS && unlikely(txn->mt_flags & MDBX_TXN_RDONLY)) {
-    rc = MDBX_EACCESS;
-    goto early_bailout;
-  }
-
-  /* Done here so we cannot fail after creating a new DB */
-  char *namedup = mdbx_strdup(table_name);
-  if (unlikely(!namedup)) {
-    rc = MDBX_ENOMEM;
-    goto early_bailout;
-  }
-
-  int err = mdbx_fastmutex_acquire(&env->me_dbi_lock);
-  if (unlikely(err != MDBX_SUCCESS)) {
-    rc = err;
-    mdbx_free(namedup);
-    goto early_bailout;
-  }
-
-  /* Import handles from env */
-  dbi_import_locked(txn);
-
-  /* Rescan after mutex acquisition & import handles */
-  for (slot = scan = txn->mt_numdbs; --scan >= CORE_DBS;) {
-    if (!txn->mt_dbxs[scan].md_name.iov_len) {
-      /* Remember this free slot */
-      slot = scan;
-      continue;
-    }
-    if (len == txn->mt_dbxs[scan].md_name.iov_len &&
-        !strncmp(table_name, txn->mt_dbxs[scan].md_name.iov_base, len)) {
-      rc = mdbx_dbi_bind(txn, scan, user_flags, keycmp, datacmp);
-      if (unlikely(rc != MDBX_SUCCESS))
-        goto later_bailout;
-      *dbi = scan;
-      goto later_exit;
-    }
-  }
-
-  if (unlikely(slot >= env->me_maxdbs)) {
-    rc = MDBX_DBS_FULL;
-    goto later_bailout;
-  }
-
-  unsigned dbiflags = DBI_FRESH | DBI_VALID | DBI_USRVALID;
-  MDBX_db db_dummy;
-  if (unlikely(rc)) {
-    /* MDBX_NOTFOUND and MDBX_CREATE: Create new DB */
-    mdbx_tassert(txn, rc == MDBX_NOTFOUND);
-    memset(&db_dummy, 0, sizeof(db_dummy));
-    db_dummy.md_root = P_INVALID;
-    db_dummy.md_flags = user_flags & DB_PERSISTENT_FLAGS;
-    data.iov_len = sizeof(db_dummy);
-    data.iov_base = &db_dummy;
-    WITH_CURSOR_TRACKING(couple.outer,
-                         rc = mdbx_cursor_put(&couple.outer, &key, &data,
-                                              F_SUBDATA | MDBX_NOOVERWRITE));
-
-    if (unlikely(rc != MDBX_SUCCESS))
-      goto later_bailout;
-
-    dbiflags |= DBI_DIRTY | DBI_CREAT;
-    txn->mt_flags |= MDBX_TXN_DIRTY;
-  }
-
-  /* Got info, register DBI in this txn */
-  memset(txn->mt_dbxs + slot, 0, sizeof(MDBX_dbx));
-  txn->mt_dbs[slot] = *(MDBX_db *)data.iov_base;
-  env->me_dbflags[slot] = 0;
-  rc = mdbx_dbi_bind(txn, slot, user_flags, keycmp, datacmp);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    mdbx_tassert(txn, (dbiflags & DBI_CREAT) == 0);
-  later_bailout:
-    *dbi = 0;
-  later_exit:
-    mdbx_free(namedup);
-  } else {
-    txn->mt_dbistate[slot] = (uint8_t)dbiflags;
-    txn->mt_dbxs[slot].md_name.iov_base = namedup;
-    txn->mt_dbxs[slot].md_name.iov_len = len;
-    txn->mt_dbiseqs[slot] = ++env->me_dbiseqs[slot];
-    if (!(dbiflags & DBI_CREAT))
-      env->me_dbflags[slot] = txn->mt_dbs[slot].md_flags | DB_VALID;
-    if (txn->mt_numdbs == slot) {
-      mdbx_compiler_barrier();
-      txn->mt_numdbs = env->me_numdbs = slot + 1;
-      if (!(txn->mt_flags & MDBX_TXN_RDONLY))
-        txn->tw.cursors[slot] = NULL;
-    }
-    mdbx_assert(env, env->me_numdbs > slot);
-    *dbi = slot;
-  }
-
-  mdbx_ensure(env, mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
-  return rc;
-}
-
-int mdbx_dbi_open(MDBX_txn *txn, const char *table_name,
-                  MDBX_db_flags_t table_flags, MDBX_dbi *dbi) {
-  return dbi_open(txn, table_name, table_flags, dbi, nullptr, nullptr);
-}
-
-int mdbx_dbi_open_ex(MDBX_txn *txn, const char *table_name,
-                     MDBX_db_flags_t table_flags, MDBX_dbi *dbi,
-                     MDBX_cmp_func *keycmp, MDBX_cmp_func *datacmp) {
-  return dbi_open(txn, table_name, table_flags, dbi, keycmp, datacmp);
-}
-
-__cold int mdbx_dbi_stat(MDBX_txn *txn, MDBX_dbi dbi, MDBX_stat *dest,
-                         size_t bytes) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!dest))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_VALID)))
-    return MDBX_BAD_DBI;
-
-  const size_t size_before_modtxnid = offsetof(MDBX_stat, ms_mod_txnid);
-  if (unlikely(bytes != sizeof(MDBX_stat)) && bytes != size_before_modtxnid)
-    return MDBX_EINVAL;
-
-  if (unlikely(txn->mt_flags & MDBX_TXN_BLOCKED))
-    return MDBX_BAD_TXN;
-
-  if (unlikely(txn->mt_dbistate[dbi] & DBI_STALE)) {
-    rc = mdbx_fetch_sdb(txn, dbi);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-  mdbx_stat0(txn->mt_env, &txn->mt_dbs[dbi], dest, bytes);
-  return MDBX_SUCCESS;
-}
-
-static int mdbx_dbi_close_locked(MDBX_env *env, MDBX_dbi dbi) {
-  mdbx_assert(env, dbi >= CORE_DBS);
-  if (unlikely(dbi >= env->me_numdbs))
-    return MDBX_BAD_DBI;
-
-  char *ptr = env->me_dbxs[dbi].md_name.iov_base;
-  /* If there was no name, this was already closed */
-  if (unlikely(!ptr))
-    return MDBX_BAD_DBI;
-
-  env->me_dbflags[dbi] = 0;
-  env->me_dbiseqs[dbi]++;
-  env->me_dbxs[dbi].md_name.iov_len = 0;
-  mdbx_memory_fence(false, true);
-  env->me_dbxs[dbi].md_name.iov_base = NULL;
-  mdbx_free(ptr);
-
-  if (env->me_numdbs == dbi + 1)
-    env->me_numdbs = dbi;
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_dbi_close(MDBX_env *env, MDBX_dbi dbi) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(dbi < CORE_DBS || dbi >= env->me_maxdbs))
-    return MDBX_BAD_DBI;
-
-  rc = mdbx_fastmutex_acquire(&env->me_dbi_lock);
-  if (likely(rc == MDBX_SUCCESS)) {
-    rc = (dbi < env->me_maxdbs && (env->me_dbflags[dbi] & DB_VALID))
-             ? mdbx_dbi_close_locked(env, dbi)
-             : MDBX_BAD_DBI;
-    mdbx_ensure(env, mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
-  }
-  return rc;
-}
-
-int mdbx_dbi_flags_ex(MDBX_txn *txn, MDBX_dbi dbi, unsigned *flags,
-                      unsigned *state) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!flags || !state))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_VALID)))
-    return MDBX_BAD_DBI;
-
-  *flags = txn->mt_dbs[dbi].md_flags & DB_PERSISTENT_FLAGS;
-  *state =
-      txn->mt_dbistate[dbi] & (DBI_FRESH | DBI_CREAT | DBI_DIRTY | DBI_STALE);
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_dbi_flags(MDBX_txn *txn, MDBX_dbi dbi, unsigned *flags) {
-  return __inline_mdbx_dbi_flags(txn, dbi, flags);
-}
-
-/* Add all the DB's pages to the free list.
- * [in] mc Cursor on the DB to free.
- * [in] subs non-Zero to check for sub-DBs in this DB.
- * Returns 0 on success, non-zero on failure. */
-static int mdbx_drop0(MDBX_cursor *mc, int subs) {
-  int rc = mdbx_page_search(mc, NULL, MDBX_PS_FIRST);
-  if (likely(rc == MDBX_SUCCESS)) {
-    MDBX_txn *txn = mc->mc_txn;
-    MDBX_cursor mx;
-    unsigned i;
-
-    /* DUPSORT sub-DBs have no ovpages/DBs. Omit scanning leaves.
-     * This also avoids any P_LEAF2 pages, which have no nodes.
-     * Also if the DB doesn't have sub-DBs and has no overflow
-     * pages, omit scanning leaves. */
-    if ((mc->mc_flags & C_SUB) || (subs | mc->mc_db->md_overflow_pages) == 0)
-      mdbx_cursor_pop(mc);
-
-    rc = mdbx_pnl_need(&txn->tw.retired_pages,
-                       mc->mc_db->md_branch_pages + mc->mc_db->md_leaf_pages +
-                           mc->mc_db->md_overflow_pages);
-    if (unlikely(rc))
-      goto done;
-
-    cursor_copy_internal(mc, &mx);
-    while (mc->mc_snum > 0) {
-      MDBX_page *mp = mc->mc_pg[mc->mc_top];
-      unsigned n = page_numkeys(mp);
-      if (IS_LEAF(mp)) {
-        for (i = 0; i < n; i++) {
-          MDBX_node *node = page_node(mp, i);
-          if (node_flags(node) & F_BIGDATA) {
-            MDBX_page *omp;
-            rc = mdbx_page_get(mc, node_largedata_pgno(node), &omp, NULL,
-                               pp_txnid4chk(mp, mc->mc_txn));
-            if (unlikely(rc))
-              goto done;
-            mdbx_cassert(mc, IS_OVERFLOW(omp));
-            rc = mdbx_page_retire(mc, omp);
-            if (unlikely(rc))
-              goto done;
-            if (!mc->mc_db->md_overflow_pages && !subs)
-              break;
-          } else if (subs && (node_flags(node) & F_SUBDATA)) {
-            rc = mdbx_xcursor_init1(mc, node, mp);
-            if (unlikely(rc != MDBX_SUCCESS))
-              goto done;
-            rc = mdbx_drop0(&mc->mc_xcursor->mx_cursor, 0);
-            if (unlikely(rc))
-              goto done;
-          }
-        }
-        if (!subs && !mc->mc_db->md_overflow_pages)
-          goto pop;
-      } else {
-        for (i = 0; i < n; i++) {
-          /* free it */
-          rc = mdbx_retire_pgno(mc, node_pgno(page_node(mp, i)));
-          if (unlikely(rc))
-            goto done;
-        }
-      }
-      if (!mc->mc_top)
-        break;
-      mdbx_cassert(mc, i <= UINT16_MAX);
-      mc->mc_ki[mc->mc_top] = (indx_t)i;
-      rc = mdbx_cursor_sibling(mc, SIBLING_RIGHT);
-      if (rc) {
-        if (unlikely(rc != MDBX_NOTFOUND))
-          goto done;
-      /* no more siblings, go back to beginning
-       * of previous level. */
-      pop:
-        mdbx_cursor_pop(mc);
-        mc->mc_ki[0] = 0;
-        for (i = 1; i < mc->mc_snum; i++) {
-          mc->mc_ki[i] = 0;
-          mc->mc_pg[i] = mx.mc_pg[i];
-        }
-      }
-    }
-    /* free it */
-    rc = mdbx_retire_pgno(mc, mc->mc_db->md_root);
-  done:
-    if (unlikely(rc))
-      txn->mt_flags |= MDBX_TXN_ERROR;
-  } else if (rc == MDBX_NOTFOUND) {
-    rc = MDBX_SUCCESS;
-  }
-  mc->mc_flags &= ~C_INITIALIZED;
-  return rc;
-}
-
-int mdbx_drop(MDBX_txn *txn, MDBX_dbi dbi, bool del) {
-  int rc = check_txn_rw(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
-    return MDBX_BAD_DBI;
-
-  MDBX_cursor *mc;
-  rc = mdbx_cursor_open(txn, dbi, &mc);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID))) {
-    rc = MDBX_BAD_DBI;
-    goto bailout;
-  }
-
-  if (unlikely(TXN_DBI_CHANGED(txn, dbi))) {
-    rc = MDBX_BAD_DBI;
-    goto bailout;
-  }
-
-  rc = mdbx_drop0(mc, mc->mc_db->md_flags & MDBX_DUPSORT);
-  /* Invalidate the dropped DB's cursors */
-  for (MDBX_cursor *m2 = txn->tw.cursors[dbi]; m2; m2 = m2->mc_next)
-    m2->mc_flags &= ~(C_INITIALIZED | C_EOF);
-  if (unlikely(rc))
-    goto bailout;
-
-  /* Can't delete the main DB */
-  if (del && dbi >= CORE_DBS) {
-    rc = mdbx_del0(txn, MAIN_DBI, &mc->mc_dbx->md_name, NULL, F_SUBDATA);
-    if (likely(rc == MDBX_SUCCESS)) {
-      txn->mt_dbistate[dbi] = DBI_STALE;
-      MDBX_env *env = txn->mt_env;
-      rc = mdbx_fastmutex_acquire(&env->me_dbi_lock);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        txn->mt_flags |= MDBX_TXN_ERROR;
-        goto bailout;
-      }
-      mdbx_dbi_close_locked(env, dbi);
-      mdbx_ensure(env,
-                  mdbx_fastmutex_release(&env->me_dbi_lock) == MDBX_SUCCESS);
-    } else {
-      txn->mt_flags |= MDBX_TXN_ERROR;
-    }
-  } else {
-    /* reset the DB record, mark it dirty */
-    txn->mt_dbistate[dbi] |= DBI_DIRTY;
-    txn->mt_dbs[dbi].md_depth = 0;
-    txn->mt_dbs[dbi].md_branch_pages = 0;
-    txn->mt_dbs[dbi].md_leaf_pages = 0;
-    txn->mt_dbs[dbi].md_overflow_pages = 0;
-    txn->mt_dbs[dbi].md_entries = 0;
-    txn->mt_dbs[dbi].md_root = P_INVALID;
-    txn->mt_dbs[dbi].md_seq = 0;
-    txn->mt_flags |= MDBX_TXN_DIRTY;
-  }
-
-bailout:
-  mdbx_cursor_close(mc);
-  return rc;
-}
-
-int mdbx_set_compare(MDBX_txn *txn, MDBX_dbi dbi, MDBX_cmp_func *cmp) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  txn->mt_dbxs[dbi].md_cmp = cmp;
-  return MDBX_SUCCESS;
-}
-
-int mdbx_set_dupsort(MDBX_txn *txn, MDBX_dbi dbi, MDBX_cmp_func *cmp) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  txn->mt_dbxs[dbi].md_dcmp = cmp;
-  return MDBX_SUCCESS;
-}
-
-__cold int mdbx_reader_list(const MDBX_env *env, MDBX_reader_list_func *func,
-                            void *ctx) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!func))
-    return MDBX_EINVAL;
-
-  rc = MDBX_RESULT_TRUE;
-  int serial = 0;
-  if (likely(env->me_lck)) {
-    const unsigned snap_nreaders =
-        atomic_load32(&env->me_lck->mti_numreaders, mo_AcquireRelease);
-    for (unsigned i = 0; i < snap_nreaders; i++) {
-      const MDBX_reader *r = env->me_lck->mti_readers + i;
-    retry_reader:;
-      const uint32_t pid = atomic_load32(&r->mr_pid, mo_AcquireRelease);
-      if (!pid)
-        continue;
-      txnid_t txnid = safe64_read(&r->mr_txnid);
-      const uint64_t tid = atomic_load64(&r->mr_tid, mo_Relaxed);
-      const pgno_t pages_used =
-          atomic_load32(&r->mr_snapshot_pages_used, mo_Relaxed);
-      const uint64_t reader_pages_retired =
-          atomic_load64(&r->mr_snapshot_pages_retired, mo_Relaxed);
-      if (unlikely(
-              txnid != safe64_read(&r->mr_txnid) ||
-              pid != atomic_load32(&r->mr_pid, mo_AcquireRelease) ||
-              tid != atomic_load64(&r->mr_tid, mo_Relaxed) ||
-              pages_used !=
-                  atomic_load32(&r->mr_snapshot_pages_used, mo_Relaxed) ||
-              reader_pages_retired !=
-                  atomic_load64(&r->mr_snapshot_pages_retired, mo_Relaxed)))
-        goto retry_reader;
-
-      mdbx_assert(env, txnid > 0);
-      if (txnid >= SAFE64_INVALID_THRESHOLD)
-        txnid = 0;
-
-      size_t bytes_used = 0;
-      size_t bytes_retained = 0;
-      uint64_t lag = 0;
-      if (txnid) {
-      retry_header:;
-        const MDBX_meta *const recent_meta = mdbx_meta_head(env);
-        const uint64_t head_pages_retired =
-            unaligned_peek_u64(4, recent_meta->mm_pages_retired);
-        const txnid_t head_txnid = mdbx_meta_txnid_fluid(env, recent_meta);
-        mdbx_compiler_barrier();
-        if (unlikely(
-                recent_meta != mdbx_meta_head(env) ||
-                head_pages_retired !=
-                    unaligned_peek_u64(4, recent_meta->mm_pages_retired)) ||
-            head_txnid != mdbx_meta_txnid_fluid(env, recent_meta))
-          goto retry_header;
-
-        lag = (head_txnid - txnid) / MDBX_TXNID_STEP;
-        bytes_used = pgno2bytes(env, pages_used);
-        bytes_retained = (head_pages_retired > reader_pages_retired)
-                             ? pgno2bytes(env, (pgno_t)(head_pages_retired -
-                                                        reader_pages_retired))
-                             : 0;
-      }
-      rc = func(ctx, ++serial, i, pid, (mdbx_tid_t)tid, txnid, lag, bytes_used,
-                bytes_retained);
-      if (unlikely(rc != MDBX_SUCCESS))
-        break;
-    }
-  }
-
-  return rc;
-}
-
-/* Insert pid into list if not already present.
- * return -1 if already present. */
-static bool __cold mdbx_pid_insert(uint32_t *ids, uint32_t pid) {
-  /* binary search of pid in list */
-  unsigned base = 0;
-  unsigned cursor = 1;
-  int val = 0;
-  unsigned n = ids[0];
-
-  while (n > 0) {
-    unsigned pivot = n >> 1;
-    cursor = base + pivot + 1;
-    val = pid - ids[cursor];
-
-    if (val < 0) {
-      n = pivot;
-    } else if (val > 0) {
-      base = cursor;
-      n -= pivot + 1;
-    } else {
-      /* found, so it's a duplicate */
-      return false;
-    }
-  }
-
-  if (val > 0)
-    ++cursor;
-
-  ids[0]++;
-  for (n = ids[0]; n > cursor; n--)
-    ids[n] = ids[n - 1];
-  ids[n] = pid;
-  return true;
-}
-
-__cold int mdbx_reader_check(MDBX_env *env, int *dead) {
-  if (dead)
-    *dead = 0;
-  return mdbx_cleanup_dead_readers(env, false, dead);
-}
-
-/* Return:
- *  MDBX_RESULT_TRUE - done and mutex recovered
- *  MDBX_SUCCESS     - done
- *  Otherwise errcode. */
-MDBX_INTERNAL_FUNC __cold int
-mdbx_cleanup_dead_readers(MDBX_env *env, int rdt_locked, int *dead) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  mdbx_assert(env, rdt_locked >= 0);
-  MDBX_lockinfo *const lck = env->me_lck;
-  if (unlikely(lck == NULL)) {
-    /* exclusive mode */
-    if (dead)
-      *dead = 0;
-    return MDBX_SUCCESS;
-  }
-
-  const unsigned snap_nreaders =
-      atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-  uint32_t pidsbuf_onstask[142];
-  uint32_t *const pids =
-      (snap_nreaders < ARRAY_LENGTH(pidsbuf_onstask))
-          ? pidsbuf_onstask
-          : mdbx_malloc((snap_nreaders + 1) * sizeof(uint32_t));
-  if (unlikely(!pids))
-    return MDBX_ENOMEM;
-
-  pids[0] = 0;
-  int count = 0;
-  for (unsigned i = 0; i < snap_nreaders; i++) {
-    const uint32_t pid =
-        atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease);
-    if (pid == 0)
-      continue /* skip empty */;
-    if (pid == env->me_pid)
-      continue /* skip self */;
-    if (!mdbx_pid_insert(pids, pid))
-      continue /* such pid already processed */;
-
-    int err = mdbx_rpid_check(env, pid);
-    if (err == MDBX_RESULT_TRUE)
-      continue /* reader is live */;
-
-    if (err != MDBX_SUCCESS) {
-      rc = err;
-      break /* mdbx_rpid_check() failed */;
-    }
-
-    /* stale reader found */
-    if (!rdt_locked) {
-      err = mdbx_rdt_lock(env);
-      if (MDBX_IS_ERROR(err)) {
-        rc = err;
-        break;
-      }
-
-      rdt_locked = -1;
-      if (err == MDBX_RESULT_TRUE) {
-        /* mutex recovered, the mdbx_ipclock_failed() checked all readers */
-        rc = MDBX_RESULT_TRUE;
-        break;
-      }
-
-      /* a other process may have clean and reused slot, recheck */
-      if (lck->mti_readers[i].mr_pid.weak != pid)
-        continue;
-
-      err = mdbx_rpid_check(env, pid);
-      if (MDBX_IS_ERROR(err)) {
-        rc = err;
-        break;
-      }
-
-      if (err != MDBX_SUCCESS)
-        continue /* the race with other process, slot reused */;
-    }
-
-    /* clean it */
-    for (unsigned j = i; j < snap_nreaders; j++) {
-      if (lck->mti_readers[j].mr_pid.weak == pid) {
-        mdbx_debug("clear stale reader pid %" PRIuPTR " txn %" PRIaTXN,
-                   (size_t)pid, lck->mti_readers[j].mr_txnid.weak);
-        atomic_store32(&lck->mti_readers[j].mr_pid, 0, mo_AcquireRelease);
-        atomic_store32(&lck->mti_readers_refresh_flag, true, mo_AcquireRelease);
-        count++;
-      }
-    }
-  }
-
-  if (likely(!MDBX_IS_ERROR(rc)))
-    atomic_store64(&lck->mti_reader_check_timestamp, mdbx_osal_monotime(),
-                   mo_AcquireRelease);
-
-  if (rdt_locked < 0)
-    mdbx_rdt_unlock(env);
-
-  if (pids != pidsbuf_onstask)
-    mdbx_free(pids);
-
-  if (dead)
-    *dead = count;
-  return rc;
-}
-
-__cold int mdbx_setup_debug(int loglevel, int flags, MDBX_debug_func *logger) {
-  const int rc = mdbx_runtime_flags | (mdbx_loglevel << 16);
-
-  if (loglevel != MDBX_LOG_DONTCHANGE)
-    mdbx_loglevel = (uint8_t)loglevel;
-
-  if (flags != MDBX_DBG_DONTCHANGE) {
-    flags &=
-#if MDBX_DEBUG
-        MDBX_DBG_ASSERT | MDBX_DBG_AUDIT | MDBX_DBG_JITTER |
-#endif
-        MDBX_DBG_DUMP | MDBX_DBG_LEGACY_MULTIOPEN | MDBX_DBG_LEGACY_OVERLAP;
-    mdbx_runtime_flags = (uint8_t)flags;
-  }
-
-  if (logger != MDBX_LOGGER_DONTCHANGE)
-    mdbx_debug_logger = logger;
-  return rc;
-}
-
-static txnid_t __cold mdbx_kick_longlived_readers(MDBX_env *env,
-                                                  const txnid_t laggard) {
-  mdbx_debug("DB size maxed out by reading #%" PRIaTXN, laggard);
-
-  int retry;
-  for (retry = 0; retry < INT_MAX; ++retry) {
-    txnid_t oldest = mdbx_recent_steady_txnid(env);
-    mdbx_assert(env, oldest < env->me_txn0->mt_txnid);
-    mdbx_assert(env, oldest >= laggard);
-    mdbx_assert(env, oldest >= env->me_oldest->weak);
-    if (oldest == laggard || unlikely(!env->me_lck /* without-LCK mode */))
-      return oldest;
-
-    if (MDBX_IS_ERROR(mdbx_cleanup_dead_readers(env, false, NULL)))
-      break;
-
-    MDBX_reader *asleep = nullptr;
-    MDBX_lockinfo *const lck = env->me_lck;
-    uint64_t oldest_retired = UINT64_MAX;
-    const unsigned snap_nreaders =
-        atomic_load32(&lck->mti_numreaders, mo_AcquireRelease);
-    for (unsigned i = 0; i < snap_nreaders; ++i) {
-    retry:
-      if (atomic_load32(&lck->mti_readers[i].mr_pid, mo_AcquireRelease)) {
-        /* mdbx_jitter4testing(true); */
-        const uint64_t snap_retired = atomic_load64(
-            &lck->mti_readers[i].mr_snapshot_pages_retired, mo_Relaxed);
-        const txnid_t snap_txnid = safe64_read(&lck->mti_readers[i].mr_txnid);
-        if (unlikely(snap_retired !=
-                         atomic_load64(
-                             &lck->mti_readers[i].mr_snapshot_pages_retired,
-                             mo_AcquireRelease) ||
-                     snap_txnid != safe64_read(&lck->mti_readers[i].mr_txnid)))
-          goto retry;
-        if (oldest > snap_txnid &&
-            laggard <= /* ignore pending updates */ snap_txnid) {
-          oldest = snap_txnid;
-          oldest_retired = snap_retired;
-          asleep = &lck->mti_readers[i];
-        }
-      }
-    }
-
-    if (laggard < oldest || !asleep) {
-      if (retry && env->me_hsr_callback) {
-        /* LY: notify end of hsr-loop */
-        const txnid_t gap = oldest - laggard;
-        env->me_hsr_callback(env, env->me_txn, 0, 0, laggard,
-                             (gap < UINT_MAX) ? (unsigned)gap : UINT_MAX, 0,
-                             -retry);
-      }
-      mdbx_notice("hsr-kick: update oldest %" PRIaTXN " -> %" PRIaTXN,
-                  env->me_oldest->weak, oldest);
-      mdbx_assert(env, env->me_oldest->weak <= oldest);
-      return atomic_store64(env->me_oldest, oldest, mo_AcquireRelease);
-    }
-
-    if (!env->me_hsr_callback)
-      break;
-
-    uint32_t pid = atomic_load32(&asleep->mr_pid, mo_AcquireRelease);
-    uint64_t tid = asleep->mr_tid.weak;
-    if (safe64_read(&asleep->mr_txnid) != laggard || pid <= 0)
-      continue;
-
-    const MDBX_meta *head_meta = mdbx_meta_head(env);
-    const txnid_t gap =
-        (mdbx_meta_txnid_stable(env, head_meta) - laggard) / MDBX_TXNID_STEP;
-    const uint64_t head_retired =
-        unaligned_peek_u64(4, head_meta->mm_pages_retired);
-    const size_t space =
-        (oldest_retired > head_retired)
-            ? pgno2bytes(env, (pgno_t)(oldest_retired - head_retired))
-            : 0;
-    int rc = env->me_hsr_callback(
-        env, env->me_txn, pid, (mdbx_tid_t)tid, laggard,
-        (gap < UINT_MAX) ? (unsigned)gap : UINT_MAX, space, retry);
-    if (rc < 0)
-      break;
-
-    if (rc > 0) {
-      if (rc == 1) {
-        safe64_reset_compare(&asleep->mr_txnid, laggard);
-      } else {
-        safe64_reset(&asleep->mr_txnid, true);
-        atomic_store64(&asleep->mr_tid, 0, mo_Relaxed);
-        atomic_store32(&asleep->mr_pid, 0, mo_Relaxed);
-      }
-      atomic_store32(&lck->mti_readers_refresh_flag, true, mo_AcquireRelease);
-    }
-  }
-
-  if (retry && env->me_hsr_callback) {
-    /* LY: notify end of hsr-loop */
-    env->me_hsr_callback(env, env->me_txn, 0, 0, laggard, 0, 0, -retry);
-  }
-  return mdbx_find_oldest(env->me_txn);
-}
-
-__cold int mdbx_env_set_syncbytes(MDBX_env *env, size_t threshold) {
-  return __inline_mdbx_env_set_syncbytes(env, threshold);
-}
-
-__cold int mdbx_env_set_syncperiod(MDBX_env *env, unsigned seconds_16dot16) {
-  return __inline_mdbx_env_set_syncperiod(env, seconds_16dot16);
-}
-
-__cold int mdbx_env_set_hsr(MDBX_env *env, MDBX_hsr_func *hsr) {
-  int rc = check_env(env);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  env->me_hsr_callback = hsr;
-  return MDBX_SUCCESS;
-}
-
-MDBX_hsr_func *__cold mdbx_env_get_hsr(const MDBX_env *env) {
-  return likely(env && env->me_signature.weak == MDBX_ME_SIGNATURE)
-             ? env->me_hsr_callback
-             : NULL;
-}
-
-#ifdef __SANITIZE_THREAD__
-/* LY: avoid tsan-trap by me_txn, mm_last_pg and mt_next_pgno */
-__attribute__((__no_sanitize_thread__, __noinline__))
-#endif
-int mdbx_txn_straggler(const MDBX_txn *txn, int *percent)
-{
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return (rc > 0) ? -rc : rc;
-
-  MDBX_env *env = txn->mt_env;
-  if (unlikely((txn->mt_flags & MDBX_TXN_RDONLY) == 0)) {
-    if (percent)
-      *percent =
-          (int)((txn->mt_next_pgno * UINT64_C(100) + txn->mt_end_pgno / 2) /
-                txn->mt_end_pgno);
-    return 0;
-  }
-
-  txnid_t recent;
-  MDBX_meta *meta;
-  do {
-    meta = mdbx_meta_head(env);
-    recent = mdbx_meta_txnid_fluid(env, meta);
-    if (percent) {
-      const pgno_t maxpg = meta->mm_geo.now;
-      *percent = (int)((meta->mm_geo.next * UINT64_C(100) + maxpg / 2) / maxpg);
-    }
-  } while (unlikely(recent != mdbx_meta_txnid_fluid(env, meta)));
-
-  txnid_t lag = (recent - txn->mt_txnid) / MDBX_TXNID_STEP;
-  return (lag > INT_MAX) ? INT_MAX : (int)lag;
-}
-
-typedef struct mdbx_walk_ctx {
-  void *mw_user;
-  MDBX_pgvisitor_func *mw_visitor;
-  MDBX_txn *mw_txn;
-  MDBX_cursor *mw_cursor;
-  bool mw_dont_check_keys_ordering;
-} mdbx_walk_ctx_t;
-
-static __cold int mdbx_walk_sdb(mdbx_walk_ctx_t *ctx, MDBX_db *const db,
-                                const char *name, int deep);
-
-static MDBX_page_type_t walk_page_type(const MDBX_page *mp) {
-  if (mp)
-    switch (mp->mp_flags) {
-    case P_BRANCH:
-      return MDBX_page_branch;
-    case P_LEAF:
-      return MDBX_page_leaf;
-    case P_LEAF | P_LEAF2:
-      return MDBX_page_dupfixed_leaf;
-    case P_OVERFLOW:
-      return MDBX_page_large;
-    case P_META:
-      return MDBX_page_meta;
-    }
-  return MDBX_page_broken;
-}
-
-/* Depth-first tree traversal. */
-static __cold int mdbx_walk_tree(mdbx_walk_ctx_t *ctx, const pgno_t pgno,
-                                 const char *name, int deep,
-                                 txnid_t parent_txnid) {
-  assert(pgno != P_INVALID);
-  MDBX_page *mp = nullptr;
-  int rc, err = mdbx_page_get(ctx->mw_cursor, pgno, &mp, NULL, parent_txnid);
-  if (err == MDBX_SUCCESS)
-    err = mdbx_page_check(ctx->mw_cursor, mp, 0);
-
-  MDBX_page_type_t type = walk_page_type(mp);
-  const int nentries = (mp && !IS_OVERFLOW(mp)) ? page_numkeys(mp) : 1;
-  unsigned npages = (mp && IS_OVERFLOW(mp)) ? mp->mp_pages : 1;
-  size_t pagesize = pgno2bytes(ctx->mw_txn->mt_env, npages);
-  size_t header_size = (mp && !IS_LEAF2(mp) && !IS_OVERFLOW(mp))
-                           ? PAGEHDRSZ + mp->mp_lower
-                           : PAGEHDRSZ;
-  size_t payload_size = 0;
-  size_t unused_size =
-      (mp && !IS_OVERFLOW(mp) ? page_room(mp) : pagesize - header_size) -
-      payload_size;
-  size_t align_bytes = 0;
-
-  if (err == MDBX_SUCCESS) {
-    /* LY: Don't use mask here, e.g bitwise
-     * (P_BRANCH|P_LEAF|P_LEAF2|P_META|P_OVERFLOW|P_SUBP).
-     * Pages should not me marked dirty/loose or otherwise. */
-    switch (mp->mp_flags) {
-    default:
-      err = MDBX_CORRUPTED;
-      break;
-    case P_BRANCH:
-      if (unlikely(nentries < 2))
-        err = MDBX_CORRUPTED;
-    case P_LEAF:
-    case P_LEAF | P_LEAF2:
-      break;
-    }
-  }
-
-  for (int i = 0; err == MDBX_SUCCESS && i < nentries;
-       align_bytes += ((payload_size + align_bytes) & 1), i++) {
-    if (type == MDBX_page_dupfixed_leaf) {
-      /* LEAF2 pages have no mp_ptrs[] or node headers */
-      payload_size += mp->mp_leaf2_ksize;
-      continue;
-    }
-
-    MDBX_node *node = page_node(mp, i);
-    payload_size += NODESIZE + node_ks(node);
-
-    if (type == MDBX_page_branch) {
-      assert(i > 0 || node_ks(node) == 0);
-      continue;
-    }
-
-    assert(type == MDBX_page_leaf);
-    switch (node_flags(node)) {
-    case 0 /* usual node */:
-      payload_size += node_ds(node);
-      break;
-
-    case F_BIGDATA /* long data on the large/overflow page */: {
-      payload_size += sizeof(pgno_t);
-      const pgno_t large_pgno = node_largedata_pgno(node);
-      const size_t over_payload = node_ds(node);
-      const size_t over_header = PAGEHDRSZ;
-      npages = 1;
-
-      MDBX_page *op;
-      err = mdbx_page_get(ctx->mw_cursor, large_pgno, &op, NULL,
-                          pp_txnid4chk(mp, ctx->mw_txn));
-      if (err == MDBX_SUCCESS)
-        err = mdbx_page_check(ctx->mw_cursor, op, 0);
-      if (err == MDBX_SUCCESS) {
-        /* LY: Don't use mask here, e.g bitwise
-         * (P_BRANCH|P_LEAF|P_LEAF2|P_META|P_OVERFLOW|P_SUBP).
-         * Pages should not me marked dirty/loose or otherwise. */
-        if (P_OVERFLOW != op->mp_flags)
-          err = bad_page(mp, "wrong page type %d for large data", op->mp_flags);
-        else
-          npages = op->mp_pages;
-      }
-
-      pagesize = pgno2bytes(ctx->mw_txn->mt_env, npages);
-      const size_t over_unused = pagesize - over_payload - over_header;
-      rc = ctx->mw_visitor(large_pgno, npages, ctx->mw_user, deep, name,
-                           pagesize, MDBX_page_large, err, 1, over_payload,
-                           over_header, over_unused);
-      if (unlikely(rc != MDBX_SUCCESS))
-        return (rc == MDBX_RESULT_TRUE) ? MDBX_SUCCESS : rc;
-    } break;
-
-    case F_SUBDATA /* sub-db */: {
-      const size_t namelen = node_ks(node);
-      payload_size += node_ds(node);
-      if (unlikely(namelen == 0 || node_ds(node) != sizeof(MDBX_db)))
-        err = MDBX_CORRUPTED;
-    } break;
-
-    case F_SUBDATA | F_DUPDATA /* dupsorted sub-tree */:
-      payload_size += sizeof(MDBX_db);
-      if (unlikely(node_ds(node) != sizeof(MDBX_db)))
-        err = MDBX_CORRUPTED;
-      break;
-
-    case F_DUPDATA /* short sub-page */: {
-      if (unlikely(node_ds(node) <= PAGEHDRSZ)) {
-        err = MDBX_CORRUPTED;
-        break;
-      }
-
-      MDBX_page *sp = node_data(node);
-      const int nsubkeys = page_numkeys(sp);
-      size_t subheader_size =
-          IS_LEAF2(sp) ? PAGEHDRSZ : PAGEHDRSZ + sp->mp_lower;
-      size_t subunused_size = page_room(sp);
-      size_t subpayload_size = 0;
-      size_t subalign_bytes = 0;
-      MDBX_page_type_t subtype;
-
-      switch (sp->mp_flags & ~P_DIRTY /* ignore for sub-pages */) {
-      case P_LEAF | P_SUBP:
-        subtype = MDBX_subpage_leaf;
-        break;
-      case P_LEAF | P_LEAF2 | P_SUBP:
-        subtype = MDBX_subpage_dupfixed_leaf;
-        break;
-      default:
-        subtype = MDBX_subpage_broken;
-        err = MDBX_CORRUPTED;
-      }
-
-      for (int j = 0; err == MDBX_SUCCESS && j < nsubkeys;
-           subalign_bytes += ((subpayload_size + subalign_bytes) & 1), j++) {
-
-        if (subtype == MDBX_subpage_dupfixed_leaf) {
-          /* LEAF2 pages have no mp_ptrs[] or node headers */
-          subpayload_size += sp->mp_leaf2_ksize;
-        } else {
-          assert(subtype == MDBX_subpage_leaf);
-          MDBX_node *subnode = page_node(sp, j);
-          subpayload_size += NODESIZE + node_ks(subnode) + node_ds(subnode);
-          if (unlikely(node_flags(subnode) != 0))
-            err = MDBX_CORRUPTED;
-        }
-      }
-
-      rc = ctx->mw_visitor(pgno, 0, ctx->mw_user, deep + 1, name, node_ds(node),
-                           subtype, err, nsubkeys, subpayload_size,
-                           subheader_size, subunused_size + subalign_bytes);
-      if (unlikely(rc != MDBX_SUCCESS))
-        return (rc == MDBX_RESULT_TRUE) ? MDBX_SUCCESS : rc;
-      header_size += subheader_size;
-      unused_size += subunused_size;
-      payload_size += subpayload_size;
-      align_bytes += subalign_bytes;
-    } break;
-
-    default:
-      err = MDBX_CORRUPTED;
-    }
-  }
-
-  rc = ctx->mw_visitor(pgno, 1, ctx->mw_user, deep, name,
-                       ctx->mw_txn->mt_env->me_psize, type, err, nentries,
-                       payload_size, header_size, unused_size + align_bytes);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return (rc == MDBX_RESULT_TRUE) ? MDBX_SUCCESS : rc;
-
-  for (int i = 0; err == MDBX_SUCCESS && i < nentries; i++) {
-    if (type == MDBX_page_dupfixed_leaf)
-      continue;
-
-    MDBX_node *node = page_node(mp, i);
-    if (type == MDBX_page_branch) {
-      err = mdbx_walk_tree(ctx, node_pgno(node), name, deep + 1,
-                           pp_txnid4chk(mp, ctx->mw_txn));
-      if (unlikely(err != MDBX_SUCCESS)) {
-        if (err == MDBX_RESULT_TRUE)
-          break;
-        return err;
-      }
-      continue;
-    }
-
-    assert(type == MDBX_page_leaf);
-    MDBX_db db;
-    switch (node_flags(node)) {
-    default:
-      continue;
-
-    case F_SUBDATA /* sub-db */: {
-      const size_t namelen = node_ks(node);
-      if (unlikely(namelen == 0 || node_ds(node) != sizeof(MDBX_db))) {
-        err = MDBX_CORRUPTED;
-        break;
-      }
-
-      char namebuf_onstask[64];
-      char *const sub_name = (namelen < sizeof(namebuf_onstask))
-                                 ? namebuf_onstask
-                                 : mdbx_malloc(namelen + 1);
-      if (sub_name) {
-        memcpy(sub_name, node_key(node), namelen);
-        sub_name[namelen] = 0;
-        memcpy(&db, node_data(node), sizeof(db));
-        err = mdbx_walk_sdb(ctx, &db, sub_name, deep + 1);
-        if (sub_name != namebuf_onstask)
-          mdbx_free(sub_name);
-      } else {
-        err = MDBX_ENOMEM;
-      }
-    } break;
-
-    case F_SUBDATA | F_DUPDATA /* dupsorted sub-tree */:
-      if (unlikely(node_ds(node) != sizeof(MDBX_db) ||
-                   ctx->mw_cursor->mc_xcursor == NULL))
-        err = MDBX_CORRUPTED;
-      else {
-        memcpy(&db, node_data(node), sizeof(db));
-        assert(ctx->mw_cursor->mc_xcursor ==
-               &container_of(ctx->mw_cursor, MDBX_cursor_couple, outer)->inner);
-        ctx->mw_cursor = &ctx->mw_cursor->mc_xcursor->mx_cursor;
-        err = mdbx_walk_tree(ctx, db.md_root, name, deep + 1,
-                             pp_txnid4chk(mp, ctx->mw_txn));
-        MDBX_xcursor *inner_xcursor =
-            container_of(ctx->mw_cursor, MDBX_xcursor, mx_cursor);
-        MDBX_cursor_couple *couple =
-            container_of(inner_xcursor, MDBX_cursor_couple, inner);
-        ctx->mw_cursor = &couple->outer;
-      }
-      break;
-    }
-  }
-
-  return MDBX_SUCCESS;
-}
-
-static __cold int mdbx_walk_sdb(mdbx_walk_ctx_t *ctx, MDBX_db *const db,
-                                const char *name, int deep) {
-  if (unlikely(db->md_root == P_INVALID))
-    return MDBX_SUCCESS; /* empty db */
-
-  MDBX_cursor_couple couple;
-  MDBX_dbx dbx = {.md_klen_min = INT_MAX};
-  uint8_t dbistate = DBI_VALID | DBI_AUDITED;
-  int rc = mdbx_couple_init(&couple, ~0u, ctx->mw_txn, db, &dbx, &dbistate);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (ctx->mw_dont_check_keys_ordering) {
-    couple.outer.mc_flags |= C_SKIPORD;
-    couple.inner.mx_cursor.mc_flags |= C_SKIPORD;
-  }
-  couple.outer.mc_next = ctx->mw_cursor;
-  ctx->mw_cursor = &couple.outer;
-  rc = mdbx_walk_tree(ctx, db->md_root, name, deep, ctx->mw_txn->mt_txnid);
-  ctx->mw_cursor = couple.outer.mc_next;
-  return rc;
-}
-
-__cold int mdbx_env_pgwalk(MDBX_txn *txn, MDBX_pgvisitor_func *visitor,
-                           void *user, bool dont_check_keys_ordering) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  mdbx_walk_ctx_t ctx;
-  memset(&ctx, 0, sizeof(ctx));
-  ctx.mw_txn = txn;
-  ctx.mw_user = user;
-  ctx.mw_visitor = visitor;
-  ctx.mw_dont_check_keys_ordering = dont_check_keys_ordering;
-
-  rc = visitor(0, NUM_METAS, user, 0, MDBX_PGWALK_META,
-               pgno2bytes(txn->mt_env, NUM_METAS), MDBX_page_meta, MDBX_SUCCESS,
-               NUM_METAS, sizeof(MDBX_meta) * NUM_METAS, PAGEHDRSZ * NUM_METAS,
-               (txn->mt_env->me_psize - sizeof(MDBX_meta) - PAGEHDRSZ) *
-                   NUM_METAS);
-  if (!MDBX_IS_ERROR(rc))
-    rc = mdbx_walk_sdb(&ctx, &txn->mt_dbs[FREE_DBI], MDBX_PGWALK_GC, 0);
-  if (!MDBX_IS_ERROR(rc))
-    rc = mdbx_walk_sdb(&ctx, &txn->mt_dbs[MAIN_DBI], MDBX_PGWALK_MAIN, 0);
-  return rc;
-}
-
-int mdbx_canary_put(MDBX_txn *txn, const MDBX_canary *canary) {
-  int rc = check_txn_rw(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (likely(canary)) {
-    if (txn->mt_canary.x == canary->x && txn->mt_canary.y == canary->y &&
-        txn->mt_canary.z == canary->z)
-      return MDBX_SUCCESS;
-    txn->mt_canary.x = canary->x;
-    txn->mt_canary.y = canary->y;
-    txn->mt_canary.z = canary->z;
-  }
-  txn->mt_canary.v = txn->mt_txnid;
-  txn->mt_flags |= MDBX_TXN_DIRTY;
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_canary_get(const MDBX_txn *txn, MDBX_canary *canary) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(canary == NULL))
-    return MDBX_EINVAL;
-
-  *canary = txn->mt_canary;
-  return MDBX_SUCCESS;
-}
-
-int mdbx_cursor_on_first(const MDBX_cursor *mc) {
-  if (unlikely(mc == NULL))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  if (!(mc->mc_flags & C_INITIALIZED))
-    return mc->mc_db->md_entries ? MDBX_RESULT_FALSE : MDBX_RESULT_TRUE;
-
-  for (unsigned i = 0; i < mc->mc_snum; ++i) {
-    if (mc->mc_ki[i])
-      return MDBX_RESULT_FALSE;
-  }
-
-  return MDBX_RESULT_TRUE;
-}
-
-int mdbx_cursor_on_last(const MDBX_cursor *mc) {
-  if (unlikely(mc == NULL))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  if (!(mc->mc_flags & C_INITIALIZED))
-    return mc->mc_db->md_entries ? MDBX_RESULT_FALSE : MDBX_RESULT_TRUE;
-
-  for (unsigned i = 0; i < mc->mc_snum; ++i) {
-    unsigned nkeys = page_numkeys(mc->mc_pg[i]);
-    if (mc->mc_ki[i] < nkeys - 1)
-      return MDBX_RESULT_FALSE;
-  }
-
-  return MDBX_RESULT_TRUE;
-}
-
-int mdbx_cursor_eof(const MDBX_cursor *mc) {
-  if (unlikely(mc == NULL))
-    return MDBX_EINVAL;
-
-  if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
-    return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                     : MDBX_EBADSIGN;
-
-  if ((mc->mc_flags & C_INITIALIZED) == 0)
-    return MDBX_RESULT_TRUE;
-
-  if (mc->mc_snum == 0)
-    return MDBX_RESULT_TRUE;
-
-  if ((mc->mc_flags & C_EOF) &&
-      mc->mc_ki[mc->mc_top] >= page_numkeys(mc->mc_pg[mc->mc_top]))
-    return MDBX_RESULT_TRUE;
-
-  return MDBX_RESULT_FALSE;
-}
-
-//------------------------------------------------------------------------------
-
-struct diff_result {
-  ptrdiff_t diff;
-  unsigned level;
-  int root_nkeys;
-};
-
-/* calculates: r = x - y */
-__hot static int cursor_diff(const MDBX_cursor *const __restrict x,
-                             const MDBX_cursor *const __restrict y,
-                             struct diff_result *const __restrict r) {
-  r->diff = 0;
-  r->level = 0;
-  r->root_nkeys = 0;
-
-  if (unlikely(x->mc_signature != MDBX_MC_LIVE))
-    return (x->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                    : MDBX_EBADSIGN;
-
-  if (unlikely(y->mc_signature != MDBX_MC_LIVE))
-    return (y->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                    : MDBX_EBADSIGN;
-
-  int rc = check_txn(x->mc_txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(x->mc_txn != y->mc_txn))
-    return MDBX_BAD_TXN;
-
-  if (unlikely(y->mc_dbi != x->mc_dbi))
-    return MDBX_EINVAL;
-
-  if (unlikely(!(y->mc_flags & x->mc_flags & C_INITIALIZED)))
-    return MDBX_ENODATA;
-
-  while (likely(r->level < y->mc_snum && r->level < x->mc_snum)) {
-    if (unlikely(y->mc_pg[r->level] != x->mc_pg[r->level]))
-      return MDBX_PROBLEM;
-
-    int nkeys = page_numkeys(y->mc_pg[r->level]);
-    assert(nkeys > 0);
-    if (r->level == 0)
-      r->root_nkeys = nkeys;
-
-    const int limit_ki = nkeys - 1;
-    const int x_ki = x->mc_ki[r->level];
-    const int y_ki = y->mc_ki[r->level];
-    r->diff = ((x_ki < limit_ki) ? x_ki : limit_ki) -
-              ((y_ki < limit_ki) ? y_ki : limit_ki);
-    if (r->diff == 0) {
-      r->level += 1;
-      continue;
-    }
-
-    while (unlikely(r->diff == 1) &&
-           likely(r->level + 1 < y->mc_snum && r->level + 1 < x->mc_snum)) {
-      r->level += 1;
-      /*   DB'PAGEs: 0------------------>MAX
-       *
-       *    CURSORs:       y < x
-       *  STACK[i ]:         |
-       *  STACK[+1]:  ...y++N|0++x...
-       */
-      nkeys = page_numkeys(y->mc_pg[r->level]);
-      r->diff = (nkeys - y->mc_ki[r->level]) + x->mc_ki[r->level];
-      assert(r->diff > 0);
-    }
-
-    while (unlikely(r->diff == -1) &&
-           likely(r->level + 1 < y->mc_snum && r->level + 1 < x->mc_snum)) {
-      r->level += 1;
-      /*   DB'PAGEs: 0------------------>MAX
-       *
-       *    CURSORs:       x < y
-       *  STACK[i ]:         |
-       *  STACK[+1]:  ...x--N|0--y...
-       */
-      nkeys = page_numkeys(x->mc_pg[r->level]);
-      r->diff = -(nkeys - x->mc_ki[r->level]) - y->mc_ki[r->level];
-      assert(r->diff < 0);
-    }
-
-    return MDBX_SUCCESS;
-  }
-
-  r->diff = CMP2INT(x->mc_flags & C_EOF, y->mc_flags & C_EOF);
-  return MDBX_SUCCESS;
-}
-
-__hot static ptrdiff_t estimate(const MDBX_db *db,
-                                struct diff_result *const __restrict dr) {
-  /*        root: branch-page    => scale = leaf-factor * branch-factor^(N-1)
-   *     level-1: branch-page(s) => scale = leaf-factor * branch-factor^2
-   *     level-2: branch-page(s) => scale = leaf-factor * branch-factor
-   *     level-N: branch-page(s) => scale = leaf-factor
-   *  leaf-level: leaf-page(s)   => scale = 1
-   */
-  ptrdiff_t btree_power = (ptrdiff_t)db->md_depth - 2 - (ptrdiff_t)dr->level;
-  if (btree_power < 0)
-    return dr->diff;
-
-  ptrdiff_t estimated =
-      (ptrdiff_t)db->md_entries * dr->diff / (ptrdiff_t)db->md_leaf_pages;
-  if (btree_power == 0)
-    return estimated;
-
-  if (db->md_depth < 4) {
-    assert(dr->level == 0 && btree_power == 1);
-    return (ptrdiff_t)db->md_entries * dr->diff / (ptrdiff_t)dr->root_nkeys;
-  }
-
-  /* average_branchpage_fillfactor = total(branch_entries) / branch_pages
-     total(branch_entries) = leaf_pages + branch_pages - 1 (root page) */
-  const size_t log2_fixedpoint = sizeof(size_t) - 1;
-  const size_t half = UINT64_C(1) << (log2_fixedpoint - 1);
-  const size_t factor =
-      ((db->md_leaf_pages + db->md_branch_pages - 1) << log2_fixedpoint) /
-      db->md_branch_pages;
-  while (1) {
-    switch ((size_t)btree_power) {
-    default: {
-      const size_t square = (factor * factor + half) >> log2_fixedpoint;
-      const size_t quad = (square * square + half) >> log2_fixedpoint;
-      do {
-        estimated = estimated * quad + half;
-        estimated >>= log2_fixedpoint;
-        btree_power -= 4;
-      } while (btree_power >= 4);
-      continue;
-    }
-    case 3:
-      estimated = estimated * factor + half;
-      estimated >>= log2_fixedpoint;
-      __fallthrough /* fall through */;
-    case 2:
-      estimated = estimated * factor + half;
-      estimated >>= log2_fixedpoint;
-      __fallthrough /* fall through */;
-    case 1:
-      estimated = estimated * factor + half;
-      estimated >>= log2_fixedpoint;
-      __fallthrough /* fall through */;
-    case 0:
-      if (unlikely(estimated > (ptrdiff_t)db->md_entries))
-        return (ptrdiff_t)db->md_entries;
-      if (unlikely(estimated < -(ptrdiff_t)db->md_entries))
-        return -(ptrdiff_t)db->md_entries;
-      return estimated;
-    }
-  }
-}
-
-int mdbx_estimate_distance(const MDBX_cursor *first, const MDBX_cursor *last,
-                           ptrdiff_t *distance_items) {
-  if (unlikely(first == NULL || last == NULL || distance_items == NULL))
-    return MDBX_EINVAL;
-
-  *distance_items = 0;
-  struct diff_result dr;
-  int rc = cursor_diff(last, first, &dr);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(dr.diff == 0) &&
-      F_ISSET(first->mc_db->md_flags & last->mc_db->md_flags,
-              MDBX_DUPSORT | C_INITIALIZED)) {
-    first = &first->mc_xcursor->mx_cursor;
-    last = &last->mc_xcursor->mx_cursor;
-    rc = cursor_diff(first, last, &dr);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  if (likely(dr.diff != 0))
-    *distance_items = estimate(first->mc_db, &dr);
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_estimate_move(const MDBX_cursor *cursor, MDBX_val *key, MDBX_val *data,
-                       MDBX_cursor_op move_op, ptrdiff_t *distance_items) {
-  if (unlikely(cursor == NULL || distance_items == NULL ||
-               move_op == MDBX_GET_CURRENT || move_op == MDBX_GET_MULTIPLE))
-    return MDBX_EINVAL;
-
-  if (unlikely(cursor->mc_signature != MDBX_MC_LIVE))
-    return (cursor->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
-                                                         : MDBX_EBADSIGN;
-
-  int rc = check_txn(cursor->mc_txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (!(cursor->mc_flags & C_INITIALIZED))
-    return MDBX_ENODATA;
-
-  MDBX_cursor_couple next;
-  cursor_copy_internal(cursor, &next.outer);
-  next.outer.mc_xcursor = NULL;
-  if (cursor->mc_db->md_flags & MDBX_DUPSORT) {
-    next.outer.mc_xcursor = &next.inner;
-    rc = mdbx_xcursor_init0(&next.outer);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    MDBX_xcursor *mx = &container_of(cursor, MDBX_cursor_couple, outer)->inner;
-    cursor_copy_internal(&mx->mx_cursor, &next.inner.mx_cursor);
-  }
-
-  MDBX_val stub = {0, 0};
-  if (data == NULL) {
-    const unsigned mask =
-        1 << MDBX_GET_BOTH | 1 << MDBX_GET_BOTH_RANGE | 1 << MDBX_SET_KEY;
-    if (unlikely(mask & (1 << move_op)))
-      return MDBX_EINVAL;
-    data = &stub;
-  }
-
-  if (key == NULL) {
-    const unsigned mask = 1 << MDBX_GET_BOTH | 1 << MDBX_GET_BOTH_RANGE |
-                          1 << MDBX_SET_KEY | 1 << MDBX_SET |
-                          1 << MDBX_SET_RANGE;
-    if (unlikely(mask & (1 << move_op)))
-      return MDBX_EINVAL;
-    key = &stub;
-  }
-
-  rc = mdbx_cursor_get(&next.outer, key, data, move_op);
-  if (unlikely(rc != MDBX_SUCCESS &&
-               (rc != MDBX_NOTFOUND || !(next.outer.mc_flags & C_INITIALIZED))))
-    return rc;
-
-  return mdbx_estimate_distance(cursor, &next.outer, distance_items);
-}
-
-int mdbx_estimate_range(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *begin_key,
-                        MDBX_val *begin_data, MDBX_val *end_key,
-                        MDBX_val *end_data, ptrdiff_t *size_items) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!size_items))
-    return MDBX_EINVAL;
-
-  if (unlikely(begin_data && (begin_key == NULL || begin_key == MDBX_EPSILON)))
-    return MDBX_EINVAL;
-
-  if (unlikely(end_data && (end_key == NULL || end_key == MDBX_EPSILON)))
-    return MDBX_EINVAL;
-
-  if (unlikely(begin_key == MDBX_EPSILON && end_key == MDBX_EPSILON))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  MDBX_cursor_couple begin;
-  /* LY: first, initialize cursor to refresh a DB in case it have DB_STALE */
-  rc = mdbx_cursor_init(&begin.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(begin.outer.mc_db->md_entries == 0)) {
-    *size_items = 0;
-    return MDBX_SUCCESS;
-  }
-
-  if (!begin_key) {
-    if (unlikely(!end_key)) {
-      /* LY: FIRST..LAST case */
-      *size_items = (ptrdiff_t)begin.outer.mc_db->md_entries;
-      return MDBX_SUCCESS;
-    }
-    MDBX_val stub = {0, 0};
-    rc = mdbx_cursor_first(&begin.outer, &stub, &stub);
-    if (unlikely(end_key == MDBX_EPSILON)) {
-      /* LY: FIRST..+epsilon case */
-      return (rc == MDBX_SUCCESS)
-                 ? mdbx_cursor_count(&begin.outer, (size_t *)size_items)
-                 : rc;
-    }
-  } else {
-    if (unlikely(begin_key == MDBX_EPSILON)) {
-      if (end_key == NULL) {
-        /* LY: -epsilon..LAST case */
-        MDBX_val stub = {0, 0};
-        rc = mdbx_cursor_last(&begin.outer, &stub, &stub);
-        return (rc == MDBX_SUCCESS)
-                   ? mdbx_cursor_count(&begin.outer, (size_t *)size_items)
-                   : rc;
-      }
-      /* LY: -epsilon..value case */
-      assert(end_key != MDBX_EPSILON);
-      begin_key = end_key;
-    } else if (unlikely(end_key == MDBX_EPSILON)) {
-      /* LY: value..+epsilon case */
-      assert(begin_key != MDBX_EPSILON);
-      end_key = begin_key;
-    }
-    if (end_key && !begin_data && !end_data &&
-        (begin_key == end_key ||
-         begin.outer.mc_dbx->md_cmp(begin_key, end_key) == 0)) {
-      /* LY: single key case */
-      int exact = 0;
-      rc = mdbx_cursor_set(&begin.outer, begin_key, NULL, MDBX_SET, &exact);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        *size_items = 0;
-        return (rc == MDBX_NOTFOUND) ? MDBX_SUCCESS : rc;
-      }
-      *size_items = 1;
-      if (begin.outer.mc_xcursor != NULL) {
-        MDBX_node *node = page_node(begin.outer.mc_pg[begin.outer.mc_top],
-                                    begin.outer.mc_ki[begin.outer.mc_top]);
-        if (F_ISSET(node_flags(node), F_DUPDATA)) {
-          /* LY: return the number of duplicates for given key */
-          mdbx_tassert(txn,
-                       begin.outer.mc_xcursor == &begin.inner &&
-                           (begin.inner.mx_cursor.mc_flags & C_INITIALIZED));
-          *size_items =
-              (sizeof(*size_items) >= sizeof(begin.inner.mx_db.md_entries) ||
-               begin.inner.mx_db.md_entries <= PTRDIFF_MAX)
-                  ? (size_t)begin.inner.mx_db.md_entries
-                  : PTRDIFF_MAX;
-        }
-      }
-      return MDBX_SUCCESS;
-    } else {
-      rc = mdbx_cursor_set(&begin.outer, begin_key, begin_data,
-                           begin_data ? MDBX_GET_BOTH_RANGE : MDBX_SET_RANGE,
-                           NULL);
-    }
-  }
-
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (rc != MDBX_NOTFOUND || !(begin.outer.mc_flags & C_INITIALIZED))
-      return rc;
-  }
-
-  MDBX_cursor_couple end;
-  rc = mdbx_cursor_init(&end.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  if (!end_key) {
-    MDBX_val stub = {0, 0};
-    rc = mdbx_cursor_last(&end.outer, &stub, &stub);
-  } else {
-    rc = mdbx_cursor_set(&end.outer, end_key, end_data,
-                         end_data ? MDBX_GET_BOTH_RANGE : MDBX_SET_RANGE, NULL);
-  }
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (rc != MDBX_NOTFOUND || !(end.outer.mc_flags & C_INITIALIZED))
-      return rc;
-  }
-
-  rc = mdbx_estimate_distance(&begin.outer, &end.outer, size_items);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  assert(*size_items >= -(ptrdiff_t)begin.outer.mc_db->md_entries &&
-         *size_items <= (ptrdiff_t)begin.outer.mc_db->md_entries);
-
-#if 0 /* LY: Was decided to returns as-is (i.e. negative) the estimation       \
-       * results for an inverted ranges. */
-
-  /* Commit 8ddfd1f34ad7cf7a3c4aa75d2e248ca7e639ed63
-     Change-Id: If59eccf7311123ab6384c4b93f9b1fed5a0a10d1 */
-
-  if (*size_items < 0) {
-    /* LY: inverted range case */
-    *size_items += (ptrdiff_t)begin.outer.mc_db->md_entries;
-  } else if (*size_items == 0 && begin_key && end_key) {
-    int cmp = begin.outer.mc_dbx->md_cmp(&origin_begin_key, &origin_end_key);
-    if (cmp == 0 && (begin.inner.mx_cursor.mc_flags & C_INITIALIZED) &&
-        begin_data && end_data)
-      cmp = begin.outer.mc_dbx->md_dcmp(&origin_begin_data, &origin_end_data);
-    if (cmp > 0) {
-      /* LY: inverted range case with empty scope */
-      *size_items = (ptrdiff_t)begin.outer.mc_db->md_entries;
-    }
-  }
-  assert(*size_items >= 0 &&
-         *size_items <= (ptrdiff_t)begin.outer.mc_db->md_entries);
-#endif
-
-  return MDBX_SUCCESS;
-}
-
-//------------------------------------------------------------------------------
-
-/* Позволяет обновить или удалить существующую запись с получением
- * в old_data предыдущего значения данных. При этом если new_data равен
- * нулю, то выполняется удаление, иначе обновление/вставка.
- *
- * Текущее значение может находиться в уже измененной (грязной) странице.
- * В этом случае страница будет перезаписана при обновлении, а само старое
- * значение утрачено. Поэтому исходно в old_data должен быть передан
- * дополнительный буфер для копирования старого значения.
- * Если переданный буфер слишком мал, то функция вернет -1, установив
- * old_data->iov_len в соответствующее значение.
- *
- * Для не-уникальных ключей также возможен второй сценарий использования,
- * когда посредством old_data из записей с одинаковым ключом для
- * удаления/обновления выбирается конкретная. Для выбора этого сценария
- * во flags следует одновременно указать MDBX_CURRENT и MDBX_NOOVERWRITE.
- * Именно эта комбинация выбрана, так как она лишена смысла, и этим позволяет
- * идентифицировать запрос такого сценария.
- *
- * Функция может быть замещена соответствующими операциями с курсорами
- * после двух доработок (TODO):
- *  - внешняя аллокация курсоров, в том числе на стеке (без malloc).
- *  - получения статуса страницы по адресу (знать о P_DIRTY).
- */
-
-int mdbx_replace_ex(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                    MDBX_val *new_data, MDBX_val *old_data,
-                    MDBX_put_flags_t flags, MDBX_preserve_func preserver,
-                    void *preserver_context) {
-  int rc = check_txn_rw(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!key || !old_data || old_data == new_data))
-    return MDBX_EINVAL;
-
-  if (unlikely(old_data->iov_base == NULL && old_data->iov_len))
-    return MDBX_EINVAL;
-
-  if (unlikely(new_data == NULL &&
-               (flags & (MDBX_CURRENT | MDBX_RESERVE)) != MDBX_CURRENT))
-    return MDBX_EINVAL;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(flags &
-               ~(MDBX_NOOVERWRITE | MDBX_NODUPDATA | MDBX_ALLDUPS |
-                 MDBX_RESERVE | MDBX_APPEND | MDBX_APPENDDUP | MDBX_CURRENT)))
-    return MDBX_EINVAL;
-
-  MDBX_cursor_couple cx;
-  rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  cx.outer.mc_next = txn->tw.cursors[dbi];
-  txn->tw.cursors[dbi] = &cx.outer;
-
-  MDBX_val present_key = *key;
-  if (F_ISSET(flags, MDBX_CURRENT | MDBX_NOOVERWRITE)) {
-    /* в old_data значение для выбора конкретного дубликата */
-    if (unlikely(!(txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT))) {
-      rc = MDBX_EINVAL;
-      goto bailout;
-    }
-
-    /* убираем лишний бит, он был признаком запрошенного режима */
-    flags -= MDBX_NOOVERWRITE;
-
-    rc = mdbx_cursor_get(&cx.outer, &present_key, old_data, MDBX_GET_BOTH);
-    if (rc != MDBX_SUCCESS)
-      goto bailout;
-  } else {
-    /* в old_data буфер для сохранения предыдущего значения */
-    if (unlikely(new_data && old_data->iov_base == new_data->iov_base))
-      return MDBX_EINVAL;
-    MDBX_val present_data;
-    rc = mdbx_cursor_get(&cx.outer, &present_key, &present_data, MDBX_SET_KEY);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      old_data->iov_base = NULL;
-      old_data->iov_len = 0;
-      if (rc != MDBX_NOTFOUND || (flags & MDBX_CURRENT))
-        goto bailout;
-    } else if (flags & MDBX_NOOVERWRITE) {
-      rc = MDBX_KEYEXIST;
-      *old_data = present_data;
-      goto bailout;
-    } else {
-      MDBX_page *page = cx.outer.mc_pg[cx.outer.mc_top];
-      if (txn->mt_dbs[dbi].md_flags & MDBX_DUPSORT) {
-        if (flags & MDBX_CURRENT) {
-          /* disallow update/delete for multi-values */
-          MDBX_node *node = page_node(page, cx.outer.mc_ki[cx.outer.mc_top]);
-          if (F_ISSET(node_flags(node), F_DUPDATA)) {
-            mdbx_tassert(txn, XCURSOR_INITED(&cx.outer) &&
-                                  cx.outer.mc_xcursor->mx_db.md_entries > 1);
-            if (cx.outer.mc_xcursor->mx_db.md_entries > 1) {
-              rc = MDBX_EMULTIVAL;
-              goto bailout;
-            }
-          }
-          /* В оригинальной LMDB флажок MDBX_CURRENT здесь приведет
-           * к замене данных без учета MDBX_DUPSORT сортировки,
-           * но здесь это в любом случае допустимо, так как мы
-           * проверили что для ключа есть только одно значение. */
-        }
-      }
-
-      if (IS_DIRTY(page)) {
-        if (new_data && cmp_lenfast(&present_data, new_data) == 0) {
-          /* если данные совпадают, то ничего делать не надо */
-          *old_data = *new_data;
-          goto bailout;
-        }
-        rc = preserver ? preserver(preserver_context, old_data,
-                                   present_data.iov_base, present_data.iov_len)
-                       : MDBX_SUCCESS;
-        if (unlikely(rc != MDBX_SUCCESS))
-          goto bailout;
-      } else {
-        *old_data = present_data;
-      }
-      flags |= MDBX_CURRENT;
-    }
-  }
-
-  if (likely(new_data))
-    rc = mdbx_cursor_put(&cx.outer, key, new_data, flags);
-  else
-    rc = mdbx_cursor_del(&cx.outer, flags & MDBX_ALLDUPS);
-
-bailout:
-  txn->tw.cursors[dbi] = cx.outer.mc_next;
-  return rc;
-}
-
-static int default_value_preserver(void *context, MDBX_val *target,
-                                   const void *src, size_t bytes) {
-  (void)context;
-  if (unlikely(target->iov_len < bytes)) {
-    target->iov_base = nullptr;
-    target->iov_len = bytes;
-    return MDBX_RESULT_TRUE;
-  }
-  memcpy(target->iov_base, src, target->iov_len = bytes);
-  return MDBX_SUCCESS;
-}
-
-int mdbx_replace(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                 MDBX_val *new_data, MDBX_val *old_data,
-                 MDBX_put_flags_t flags) {
-  return mdbx_replace_ex(txn, dbi, key, new_data, old_data, flags,
-                         default_value_preserver, nullptr);
-}
-
-/* Функция сообщает находится ли указанный адрес в "грязной" странице у
- * заданной пишущей транзакции. В конечном счете это позволяет избавиться от
- * лишнего копирования данных из НЕ-грязных страниц.
- *
- * "Грязные" страницы - это те, которые уже были изменены в ходе пишущей
- * транзакции. Соответственно, какие-либо дальнейшие изменения могут привести
- * к перезаписи таких страниц. Поэтому все функции, выполняющие изменения, в
- * качестве аргументов НЕ должны получать указатели на данные в таких
- * страницах. В свою очередь "НЕ грязные" страницы перед модификацией будут
- * скопированы.
- *
- * Другими словами, данные из "грязных" страниц должны быть либо скопированы
- * перед передачей в качестве аргументов для дальнейших модификаций, либо
- * отвергнуты на стадии проверки корректности аргументов.
- *
- * Таким образом, функция позволяет как избавиться от лишнего копирования,
- * так и выполнить более полную проверку аргументов.
- *
- * ВАЖНО: Передаваемый указатель должен указывать на начало данных. Только
- * так гарантируется что актуальный заголовок страницы будет физически
- * расположен в той-же странице памяти, в том числе для многостраничных
- * P_OVERFLOW страниц с длинными данными. */
-int mdbx_is_dirty(const MDBX_txn *txn, const void *ptr) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  const MDBX_env *env = txn->mt_env;
-  const ptrdiff_t offset = (uint8_t *)ptr - env->me_map;
-  if (offset >= 0) {
-    const pgno_t pgno = bytes2pgno(env, offset);
-    if (likely(pgno < txn->mt_next_pgno)) {
-      if (txn->mt_flags & MDBX_TXN_RDONLY)
-        return MDBX_RESULT_FALSE;
-
-      const MDBX_page *page = pgno2page(env, pgno);
-      if (unlikely(page->mp_pgno != pgno)) {
-        /* The ptr pointed into middle of a large page,
-         * not to the beginning of a data. */
-        return MDBX_EINVAL;
-      }
-      if (unlikely(page->mp_flags & (P_DIRTY | P_LOOSE | P_KEEP | P_META)))
-        return MDBX_RESULT_TRUE;
-      if (likely(txn->tw.spill_pages == nullptr))
-        return MDBX_RESULT_FALSE;
-      return mdbx_pnl_exist(txn->tw.spill_pages, pgno << 1) ? MDBX_RESULT_TRUE
-                                                            : MDBX_RESULT_FALSE;
-    }
-    if ((size_t)offset < env->me_dxb_mmap.limit) {
-      /* Указатель адресует что-то в пределах mmap, но за границей
-       * распределенных страниц. Такое может случится если mdbx_is_dirty()
-       * вызывается после операции, в ходе которой грязная страница попала
-       * в loose и затем была возвращена в нераспределенное пространство. */
-      return MDBX_RESULT_TRUE;
-    }
-  }
-
-  /* Страница вне используемого mmap-диапазона, т.е. либо в функцию был
-   * передан некорректный адрес, либо адрес в теневой странице, которая была
-   * выделена посредством malloc().
-   *
-   * Для режима WRITE_MAP режима страница однозначно "не грязная",
-   * а для режимов без WRITE_MAP следует просматривать списки dirty
-   * и spilled страниц у каких-либо транзакций (в том числе дочерних).
-   *
-   * Поэтому для WRITE_MAP возвращаем false, а для остальных режимов
-   * всегда true. Такая логика имеет ряд преимуществ:
-   *  - не тратим время на просмотр списков;
-   *  - результат всегда безопасен (может быть ложно-положительным,
-   *    но не ложно-отрицательным);
-   *  - результат не зависит от вложенности транзакций и от относительного
-   *    положения переданной транзакции в этой рекурсии. */
-  return (env->me_flags & MDBX_WRITEMAP) ? MDBX_RESULT_FALSE : MDBX_RESULT_TRUE;
-}
-
-int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
-                      uint64_t increment) {
-  int rc = check_txn(txn, MDBX_TXN_BLOCKED);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (unlikely(!mdbx_txn_dbi_exists(txn, dbi, DBI_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(txn->mt_dbistate[dbi] & DBI_STALE)) {
-    rc = mdbx_fetch_sdb(txn, dbi);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-  }
-
-  MDBX_db *dbs = &txn->mt_dbs[dbi];
-  if (likely(result))
-    *result = dbs->md_seq;
-
-  if (likely(increment > 0)) {
-    if (unlikely(txn->mt_flags & MDBX_TXN_RDONLY))
-      return MDBX_EACCESS;
-
-    uint64_t new = dbs->md_seq + increment;
-    if (unlikely(new < increment))
-      return MDBX_RESULT_TRUE;
-
-    mdbx_tassert(txn, new > dbs->md_seq);
-    dbs->md_seq = new;
-    txn->mt_flags |= MDBX_TXN_DIRTY;
-    txn->mt_dbistate[dbi] |= DBI_DIRTY;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-/*----------------------------------------------------------------------------*/
-
-__cold MDBX_NOTHROW_CONST_FUNCTION intptr_t mdbx_limits_pgsize_min(void) {
-  return __inline_mdbx_limits_pgsize_min();
-}
-
-__cold MDBX_NOTHROW_CONST_FUNCTION intptr_t mdbx_limits_pgsize_max(void) {
-  return __inline_mdbx_limits_pgsize_max();
-}
-
-__cold intptr_t mdbx_limits_dbsize_min(intptr_t pagesize) {
-  if (pagesize < 1)
-    pagesize = (intptr_t)mdbx_default_pagesize();
-  else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
-                    pagesize > (intptr_t)MAX_PAGESIZE ||
-                    !is_powerof2((size_t)pagesize)))
-    return -1;
-
-  return MIN_PAGENO * pagesize;
-}
-
-__cold intptr_t mdbx_limits_dbsize_max(intptr_t pagesize) {
-  if (pagesize < 1)
-    pagesize = (intptr_t)mdbx_default_pagesize();
-  else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
-                    pagesize > (intptr_t)MAX_PAGESIZE ||
-                    !is_powerof2((size_t)pagesize)))
-    return -1;
-
-  STATIC_ASSERT(MAX_MAPSIZE < INTPTR_MAX);
-  const uint64_t limit = MAX_PAGENO * (uint64_t)pagesize;
-  return (limit < (intptr_t)MAX_MAPSIZE) ? (intptr_t)limit
-                                         : (intptr_t)MAX_MAPSIZE;
-}
-
-__cold intptr_t mdbx_limits_txnsize_max(intptr_t pagesize) {
-  if (pagesize < 1)
-    pagesize = (intptr_t)mdbx_default_pagesize();
-  else if (unlikely(pagesize < (intptr_t)MIN_PAGESIZE ||
-                    pagesize > (intptr_t)MAX_PAGESIZE ||
-                    !is_powerof2((size_t)pagesize)))
-    return -1;
-
-  STATIC_ASSERT(MAX_MAPSIZE < INTPTR_MAX);
-  const uint64_t limit = pagesize * (uint64_t)(MDBX_PGL_LIMIT - 1);
-  return (limit < (intptr_t)MAX_MAPSIZE) ? (intptr_t)limit
-                                         : (intptr_t)MAX_MAPSIZE;
-}
-
-/*** Key-making functions to avoid custom comparators *************************/
-
-static __always_inline double key2double(const int64_t key) {
-  union {
-    uint64_t u;
-    double f;
-  } casting;
-
-  casting.u = (key < 0) ? key + UINT64_C(0x8000000000000000)
-                        : UINT64_C(0xffffFFFFffffFFFF) - key;
-  return casting.f;
-}
-
-static __always_inline uint64_t double2key(const double *const ptr) {
-  STATIC_ASSERT(sizeof(double) == sizeof(int64_t));
-  const int64_t i = *(const int64_t *)ptr;
-  const uint64_t u = (i < 0) ? UINT64_C(0xffffFFFFffffFFFF) - i
-                             : i + UINT64_C(0x8000000000000000);
-  if (mdbx_assert_enabled()) {
-    const double f = key2double(u);
-    assert(memcmp(&f, ptr, 8) == 0);
-  }
-  return u;
-}
-
-static __always_inline float key2float(const int32_t key) {
-  union {
-    uint32_t u;
-    float f;
-  } casting;
-
-  casting.u =
-      (key < 0) ? key + UINT32_C(0x80000000) : UINT32_C(0xffffFFFF) - key;
-  return casting.f;
-}
-
-static __always_inline uint32_t float2key(const float *const ptr) {
-  STATIC_ASSERT(sizeof(float) == sizeof(int32_t));
-  const int32_t i = *(const int32_t *)ptr;
-  const uint32_t u =
-      (i < 0) ? UINT32_C(0xffffFFFF) - i : i + UINT32_C(0x80000000);
-  if (mdbx_assert_enabled()) {
-    const float f = key2float(u);
-    assert(memcmp(&f, ptr, 4) == 0);
-  }
-  return u;
-}
-
-uint64_t mdbx_key_from_double(const double ieee754_64bit) {
-  return double2key(&ieee754_64bit);
-}
-
-uint64_t mdbx_key_from_ptrdouble(const double *const ieee754_64bit) {
-  return double2key(ieee754_64bit);
-}
-
-uint32_t mdbx_key_from_float(const float ieee754_32bit) {
-  return float2key(&ieee754_32bit);
-}
-
-uint32_t mdbx_key_from_ptrfloat(const float *const ieee754_32bit) {
-  return float2key(ieee754_32bit);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION uint64_t mdbx_key_from_int64(const int64_t i64) {
-  return __inline_mdbx_key_from_int64(i64);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION uint32_t mdbx_key_from_int32(const int32_t i32) {
-  return __inline_mdbx_key_from_int32(i32);
-}
-
-#define IEEE754_DOUBLE_MANTISSA_SIZE 52
-#define IEEE754_DOUBLE_EXPONENTA_BIAS 0x3FF
-#define IEEE754_DOUBLE_EXPONENTA_MAX 0x7FF
-#define IEEE754_DOUBLE_IMPLICIT_LEAD UINT64_C(0x0010000000000000)
-#define IEEE754_DOUBLE_MANTISSA_MASK UINT64_C(0x000FFFFFFFFFFFFF)
-#define IEEE754_DOUBLE_MANTISSA_AMAX UINT64_C(0x001FFFFFFFFFFFFF)
-
-static __inline int clz64(uint64_t value) {
-#if __GNUC_PREREQ(4, 1) || __has_builtin(__builtin_clzl)
-  if (sizeof(value) == sizeof(int))
-    return __builtin_clz(value);
-  if (sizeof(value) == sizeof(long))
-    return __builtin_clzl(value);
-#if (defined(__SIZEOF_LONG_LONG__) && __SIZEOF_LONG_LONG__ == 8) ||            \
-    __has_builtin(__builtin_clzll)
-  return __builtin_clzll(value);
-#endif /* have(long long) && long long == uint64_t */
-#endif /* GNU C */
-
-#if defined(_MSC_VER)
-  unsigned long index;
-#if defined(_M_AMD64) || defined(_M_ARM64) || defined(_M_X64)
-  _BitScanReverse64(&index, value);
-  return 63 - index;
-#else
-  if (value > UINT32_MAX) {
-    _BitScanReverse(&index, (uint32_t)(value >> 32));
-    return 31 - index;
-  }
-  _BitScanReverse(&index, (uint32_t)value);
-  return 63 - index;
-#endif
-#endif /* MSVC */
-
-  value |= value >> 1;
-  value |= value >> 2;
-  value |= value >> 4;
-  value |= value >> 8;
-  value |= value >> 16;
-  value |= value >> 32;
-  static const uint8_t debruijn_clz64[64] = {
-      63, 16, 62, 7,  15, 36, 61, 3,  6,  14, 22, 26, 35, 47, 60, 2,
-      9,  5,  28, 11, 13, 21, 42, 19, 25, 31, 34, 40, 46, 52, 59, 1,
-      17, 8,  37, 4,  23, 27, 48, 10, 29, 12, 43, 20, 32, 41, 53, 18,
-      38, 24, 49, 30, 44, 33, 54, 39, 50, 45, 55, 51, 56, 57, 58, 0};
-  return debruijn_clz64[value * UINT64_C(0x03F79D71B4CB0A89) >> 58];
-}
-
-static __inline uint64_t round_mantissa(const uint64_t u64, int shift) {
-  assert(shift < 0 && u64 > 0);
-  shift = -shift;
-  const unsigned half = 1 << (shift - 1);
-  const unsigned lsb = 1 & (unsigned)(u64 >> shift);
-  const unsigned tie2even = 1 ^ lsb;
-  return (u64 + half - tie2even) >> shift;
-}
-
-uint64_t mdbx_key_from_jsonInteger(const int64_t json_integer) {
-  const uint64_t bias = UINT64_C(0x8000000000000000);
-  if (json_integer > 0) {
-    const uint64_t u64 = json_integer;
-    int shift = clz64(u64) - (64 - IEEE754_DOUBLE_MANTISSA_SIZE - 1);
-    uint64_t mantissa = u64 << shift;
-    if (unlikely(shift < 0)) {
-      mantissa = round_mantissa(u64, shift);
-      if (mantissa > IEEE754_DOUBLE_MANTISSA_AMAX)
-        mantissa = round_mantissa(u64, --shift);
-    }
-
-    assert(mantissa >= IEEE754_DOUBLE_IMPLICIT_LEAD &&
-           mantissa <= IEEE754_DOUBLE_MANTISSA_AMAX);
-    const uint64_t exponent =
-        IEEE754_DOUBLE_EXPONENTA_BIAS + IEEE754_DOUBLE_MANTISSA_SIZE - shift;
-    assert(exponent > 0 && exponent <= IEEE754_DOUBLE_EXPONENTA_MAX);
-    const uint64_t key = bias + (exponent << IEEE754_DOUBLE_MANTISSA_SIZE) +
-                         (mantissa - IEEE754_DOUBLE_IMPLICIT_LEAD);
-#if !defined(_MSC_VER) ||                                                      \
-    defined(                                                                   \
-        _DEBUG) /* Workaround for MSVC error LNK2019: unresolved external      \
-                   symbol __except1 referenced in function __ftol3_except */
-    assert(key == mdbx_key_from_double((double)json_integer));
-#endif /* Workaround for MSVC */
-    return key;
-  }
-
-  if (json_integer < 0) {
-    const uint64_t u64 = -json_integer;
-    int shift = clz64(u64) - (64 - IEEE754_DOUBLE_MANTISSA_SIZE - 1);
-    uint64_t mantissa = u64 << shift;
-    if (unlikely(shift < 0)) {
-      mantissa = round_mantissa(u64, shift);
-      if (mantissa > IEEE754_DOUBLE_MANTISSA_AMAX)
-        mantissa = round_mantissa(u64, --shift);
-    }
-
-    assert(mantissa >= IEEE754_DOUBLE_IMPLICIT_LEAD &&
-           mantissa <= IEEE754_DOUBLE_MANTISSA_AMAX);
-    const uint64_t exponent =
-        IEEE754_DOUBLE_EXPONENTA_BIAS + IEEE754_DOUBLE_MANTISSA_SIZE - shift;
-    assert(exponent > 0 && exponent <= IEEE754_DOUBLE_EXPONENTA_MAX);
-    const uint64_t key = bias - 1 - (exponent << IEEE754_DOUBLE_MANTISSA_SIZE) -
-                         (mantissa - IEEE754_DOUBLE_IMPLICIT_LEAD);
-#if !defined(_MSC_VER) ||                                                      \
-    defined(                                                                   \
-        _DEBUG) /* Workaround for MSVC error LNK2019: unresolved external      \
-                   symbol __except1 referenced in function __ftol3_except */
-    assert(key == mdbx_key_from_double((double)json_integer));
-#endif /* Workaround for MSVC */
-    return key;
-  }
-
-  return bias;
-}
-
-int64_t mdbx_jsonInteger_from_key(const MDBX_val v) {
-  assert(v.iov_len == 8);
-  const uint64_t key = unaligned_peek_u64(2, v.iov_base);
-  const uint64_t bias = UINT64_C(0x8000000000000000);
-  const uint64_t covalent = (key > bias) ? key - bias : bias - key - 1;
-  const int shift = IEEE754_DOUBLE_EXPONENTA_BIAS + 63 -
-                    (IEEE754_DOUBLE_EXPONENTA_MAX &
-                     (int)(covalent >> IEEE754_DOUBLE_MANTISSA_SIZE));
-  if (unlikely(shift < 1))
-    return (key < bias) ? INT64_MIN : INT64_MAX;
-  if (unlikely(shift > 63))
-    return 0;
-
-  const uint64_t unscaled = ((covalent & IEEE754_DOUBLE_MANTISSA_MASK)
-                             << (63 - IEEE754_DOUBLE_MANTISSA_SIZE)) +
-                            bias;
-  const int64_t absolute = unscaled >> shift;
-  const int64_t value = (key < bias) ? -absolute : absolute;
-  assert(key == mdbx_key_from_jsonInteger(value) ||
-         (mdbx_key_from_jsonInteger(value - 1) < key &&
-          key < mdbx_key_from_jsonInteger(value + 1)));
-  return value;
-}
-
-double mdbx_double_from_key(const MDBX_val v) {
-  assert(v.iov_len == 8);
-  return key2double(unaligned_peek_u64(2, v.iov_base));
-}
-
-float mdbx_float_from_key(const MDBX_val v) {
-  assert(v.iov_len == 4);
-  return key2float(unaligned_peek_u32(2, v.iov_base));
-}
-
-int32_t mdbx_int32_from_key(const MDBX_val v) {
-  assert(v.iov_len == 4);
-  return (int32_t)(unaligned_peek_u32(2, v.iov_base) - UINT32_C(0x80000000));
-}
-
-int64_t mdbx_int64_from_key(const MDBX_val v) {
-  assert(v.iov_len == 8);
-  return (int64_t)(unaligned_peek_u64(2, v.iov_base) -
-                   UINT64_C(0x8000000000000000));
-}
-
-__cold MDBX_cmp_func *mdbx_get_keycmp(unsigned flags) {
-  return get_default_keycmp(flags);
-}
-
-__cold MDBX_cmp_func *mdbx_get_datacmp(unsigned flags) {
-  return get_default_datacmp(flags);
-}
-
-__cold int mdbx_env_set_option(MDBX_env *env, const MDBX_option_t option,
-                               const uint64_t value) {
-  int err = check_env(env);
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-
-  const bool lock_needed = (env->me_map && env->me_txn0 &&
-                            env->me_txn0->mt_owner != mdbx_thread_self());
-  bool should_unlock = false;
-  switch (option) {
-  case MDBX_opt_sync_bytes:
-    if (unlikely(env->me_flags & MDBX_RDONLY))
-      return MDBX_EACCESS;
-    if (unlikely(!env->me_autosync_threshold))
-      return MDBX_EPERM;
-    if (sizeof(value) > sizeof(size_t) && unlikely(value != (size_t)value))
-      return MDBX_TOO_LARGE;
-    if (atomic_store32(env->me_autosync_threshold,
-                       bytes2pgno(env, (size_t)value + env->me_psize - 1),
-                       mo_Relaxed) != 0) {
-      err = mdbx_env_sync_poll(env);
-      if (unlikely(MDBX_IS_ERROR(err)))
-        return err;
-    }
-    break;
-
-  case MDBX_opt_sync_period:
-    if (unlikely(env->me_flags & MDBX_RDONLY))
-      return MDBX_EACCESS;
-    if (unlikely(!env->me_autosync_period))
-      return MDBX_EPERM;
-    if (unlikely(value > UINT32_MAX))
-      return MDBX_TOO_LARGE;
-    if (atomic_store64(env->me_autosync_period,
-                       mdbx_osal_16dot16_to_monotime((uint32_t)value),
-                       mo_Relaxed) != 0) {
-      err = mdbx_env_sync_poll(env);
-      if (unlikely(MDBX_IS_ERROR(err)))
-        return err;
-    }
-    break;
-
-  case MDBX_opt_max_db:
-    if (unlikely(value > MDBX_MAX_DBI))
-      return MDBX_EINVAL;
-    if (unlikely(env->me_map))
-      return MDBX_EPERM;
-    env->me_maxdbs = (unsigned)value + CORE_DBS;
-    break;
-
-  case MDBX_opt_max_readers:
-    if (unlikely(value < 1 || value > MDBX_READERS_LIMIT))
-      return MDBX_EINVAL;
-    if (unlikely(env->me_map))
-      return MDBX_EPERM;
-    env->me_maxreaders = (unsigned)value;
-    break;
-
-  case MDBX_opt_dp_reserve_limit:
-    if (unlikely(value > INT_MAX))
-      return MDBX_EINVAL;
-    if (env->me_options.dp_reserve_limit != (unsigned)value) {
-      if (lock_needed) {
-        err = mdbx_txn_lock(env, false);
-        if (unlikely(err != MDBX_SUCCESS))
-          return err;
-        should_unlock = true;
-      }
-      env->me_options.dp_reserve_limit = (unsigned)value;
-      while (env->me_dp_reserve_len > env->me_options.dp_reserve_limit) {
-        mdbx_assert(env, env->me_dp_reserve != NULL);
-        MDBX_page *dp = env->me_dp_reserve;
-        ASAN_UNPOISON_MEMORY_REGION(dp, env->me_psize);
-        VALGRIND_MAKE_MEM_DEFINED(&dp->mp_next, sizeof(dp->mp_next));
-        env->me_dp_reserve = dp->mp_next;
-        VALGRIND_MEMPOOL_FREE(env, dp);
-        mdbx_free(dp);
-        env->me_dp_reserve_len -= 1;
-      }
-    }
-    break;
-
-  case MDBX_opt_rp_augment_limit:
-    if (unlikely(value > MDBX_PGL_LIMIT))
-      return MDBX_EINVAL;
-    env->me_options.rp_augment_limit = (unsigned)value;
-    break;
-
-  case MDBX_opt_txn_dp_limit:
-  case MDBX_opt_txn_dp_initial:
-    if (unlikely(value > MDBX_PGL_LIMIT || value < CURSOR_STACK * 4 ||
-                 value > bytes2pgno(env, env->me_dbgeo.upper) - NUM_METAS))
-      return MDBX_EINVAL;
-    if (unlikely(env->me_txn0 == NULL))
-      return MDBX_EACCESS;
-    if (lock_needed) {
-      err = mdbx_txn_lock(env, false);
-      if (unlikely(err != MDBX_SUCCESS))
-        return err;
-      should_unlock = true;
-    }
-    if (env->me_txn)
-      err = MDBX_EPERM /* unable change during transaction */;
-    else {
-      mdbx_dpl_clear(env->me_txn0->tw.dirtylist);
-      const unsigned value32 = (unsigned)value;
-      if (option == MDBX_opt_txn_dp_initial &&
-          env->me_options.dp_initial != value32) {
-        if (env->me_options.dp_limit < value32)
-          env->me_options.dp_limit = value32;
-        if (env->me_txn0->tw.dirtylist->allocated < value32 &&
-            !mdbx_dpl_reserve(env->me_txn0, value32))
-          err = MDBX_ENOMEM;
-        else
-          env->me_options.dp_initial = value32;
-      }
-      if (option == MDBX_opt_txn_dp_limit &&
-          env->me_options.dp_limit != value32) {
-        if (env->me_txn0->tw.dirtylist->allocated > value32 &&
-            !mdbx_dpl_reserve(env->me_txn0, value32))
-          err = MDBX_ENOMEM;
-        else {
-          if (env->me_options.dp_initial > value32)
-            env->me_options.dp_initial = value32;
-          env->me_options.dp_limit = value32;
-        }
-      }
-    }
-    break;
-
-  case MDBX_opt_spill_max_denominator:
-    if (unlikely(value > 255))
-      return MDBX_EINVAL;
-    env->me_options.spill_max_denominator = (uint8_t)value;
-    break;
-  case MDBX_opt_spill_min_denominator:
-    if (unlikely(value > 255))
-      return MDBX_EINVAL;
-    env->me_options.spill_min_denominator = (uint8_t)value;
-    break;
-  case MDBX_opt_spill_parent4child_denominator:
-    if (unlikely(value > 255))
-      return MDBX_EINVAL;
-    env->me_options.spill_parent4child_denominator = (uint8_t)value;
-    break;
-
-  case MDBX_opt_loose_limit:
-    if (unlikely(value > 255))
-      return MDBX_EINVAL;
-    env->me_options.dp_loose_limit = (uint8_t)value;
-    break;
-
-  default:
-    return MDBX_EINVAL;
-  }
-
-  if (should_unlock)
-    mdbx_txn_unlock(env);
-  return err;
-}
-
-__cold int mdbx_env_get_option(const MDBX_env *env, const MDBX_option_t option,
-                               uint64_t *value) {
-  int err = check_env(env);
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-  if (unlikely(!value))
-    return MDBX_EINVAL;
-
-  switch (option) {
-  case MDBX_opt_sync_bytes:
-    if (unlikely(!env->me_autosync_threshold))
-      return MDBX_EPERM;
-    *value =
-        pgno2bytes(env, atomic_load32(env->me_autosync_threshold, mo_Relaxed));
-    break;
-
-  case MDBX_opt_sync_period:
-    if (unlikely(!env->me_autosync_period))
-      return MDBX_EPERM;
-    *value = mdbx_osal_monotime_to_16dot16(
-        atomic_load64(env->me_autosync_period, mo_Relaxed));
-    break;
-
-  case MDBX_opt_max_db:
-    *value = env->me_maxdbs - CORE_DBS;
-    break;
-
-  case MDBX_opt_max_readers:
-    *value = env->me_maxreaders;
-    break;
-
-  case MDBX_opt_dp_reserve_limit:
-    *value = env->me_options.dp_reserve_limit;
-    break;
-
-  case MDBX_opt_rp_augment_limit:
-    *value = env->me_options.rp_augment_limit;
-    break;
-
-  case MDBX_opt_txn_dp_limit:
-    *value = env->me_options.dp_limit;
-    break;
-  case MDBX_opt_txn_dp_initial:
-    *value = env->me_options.dp_initial;
-    break;
-
-  case MDBX_opt_spill_max_denominator:
-    *value = env->me_options.spill_max_denominator;
-    break;
-  case MDBX_opt_spill_min_denominator:
-    *value = env->me_options.spill_min_denominator;
-    break;
-  case MDBX_opt_spill_parent4child_denominator:
-    *value = env->me_options.spill_parent4child_denominator;
-    break;
-
-  case MDBX_opt_loose_limit:
-    *value = env->me_options.dp_loose_limit;
-    break;
-
-  default:
-    return MDBX_EINVAL;
-  }
-
-  return MDBX_SUCCESS;
-}
-
-/*** Attribute support functions for Nexenta **********************************/
-#ifdef MDBX_NEXENTA_ATTRS
-
-static __inline int mdbx_attr_peek(MDBX_val *data, mdbx_attr_t *attrptr) {
-  if (unlikely(data->iov_len < sizeof(mdbx_attr_t)))
-    return MDBX_INCOMPATIBLE;
-
-  if (likely(attrptr != NULL))
-    *attrptr = *(mdbx_attr_t *)data->iov_base;
-  data->iov_len -= sizeof(mdbx_attr_t);
-  data->iov_base =
-      likely(data->iov_len > 0) ? ((mdbx_attr_t *)data->iov_base) + 1 : NULL;
-
-  return MDBX_SUCCESS;
-}
-
-static __inline int mdbx_attr_poke(MDBX_val *reserved, MDBX_val *data,
-                                   mdbx_attr_t attr, MDBX_put_flags_t flags) {
-  mdbx_attr_t *space = reserved->iov_base;
-  if (flags & MDBX_RESERVE) {
-    if (likely(data != NULL)) {
-      data->iov_base = data->iov_len ? space + 1 : NULL;
-    }
-  } else {
-    *space = attr;
-    if (likely(data != NULL)) {
-      memcpy(space + 1, data->iov_base, data->iov_len);
-    }
-  }
-
-  return MDBX_SUCCESS;
-}
-
-int mdbx_cursor_get_attr(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
-                         mdbx_attr_t *attrptr, MDBX_cursor_op op) {
-  int rc = mdbx_cursor_get(mc, key, data, op);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  return mdbx_attr_peek(data, attrptr);
-}
-
-int mdbx_get_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
-                  uint64_t *attrptr) {
-  int rc = mdbx_get(txn, dbi, key, data);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  return mdbx_attr_peek(data, attrptr);
-}
-
-int mdbx_put_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
-                  mdbx_attr_t attr, MDBX_put_flags_t flags) {
-  MDBX_val reserve;
-  reserve.iov_base = NULL;
-  reserve.iov_len = (data ? data->iov_len : 0) + sizeof(mdbx_attr_t);
-
-  int rc = mdbx_put(txn, dbi, key, &reserve, flags | MDBX_RESERVE);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  return mdbx_attr_poke(&reserve, data, attr, flags);
-}
-
-int mdbx_cursor_put_attr(MDBX_cursor *cursor, MDBX_val *key, MDBX_val *data,
-                         mdbx_attr_t attr, MDBX_put_flags_t flags) {
-  MDBX_val reserve;
-  reserve.iov_base = NULL;
-  reserve.iov_len = (data ? data->iov_len : 0) + sizeof(mdbx_attr_t);
-
-  int rc = mdbx_cursor_put(cursor, key, &reserve, flags | MDBX_RESERVE);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  return mdbx_attr_poke(&reserve, data, attr, flags);
-}
-
-int mdbx_set_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
-                  mdbx_attr_t attr) {
-  if (unlikely(!key || !txn))
-    return MDBX_EINVAL;
-
-  if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
-    return MDBX_EBADSIGN;
-
-  if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
-    return MDBX_BAD_DBI;
-
-  if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY | MDBX_TXN_BLOCKED)))
-    return (txn->mt_flags & MDBX_TXN_RDONLY) ? MDBX_EACCESS : MDBX_BAD_TXN;
-
-  MDBX_cursor_couple cx;
-  MDBX_val old_data;
-  int rc = mdbx_cursor_init(&cx.outer, txn, dbi);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-  rc = mdbx_cursor_set(&cx.outer, key, &old_data, MDBX_SET, NULL);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    if (rc == MDBX_NOTFOUND && data) {
-      cx.outer.mc_next = txn->tw.cursors[dbi];
-      txn->tw.cursors[dbi] = &cx.outer;
-      rc = mdbx_cursor_put_attr(&cx.outer, key, data, attr, 0);
-      txn->tw.cursors[dbi] = cx.outer.mc_next;
-    }
-    return rc;
-  }
-
-  mdbx_attr_t old_attr = 0;
-  rc = mdbx_attr_peek(&old_data, &old_attr);
-  if (unlikely(rc != MDBX_SUCCESS))
-    return rc;
-
-  if (old_attr == attr && (!data || (data->iov_len == old_data.iov_len &&
-                                     memcmp(data->iov_base, old_data.iov_base,
-                                            old_data.iov_len) == 0)))
-    return MDBX_SUCCESS;
-
-  cx.outer.mc_next = txn->tw.cursors[dbi];
-  txn->tw.cursors[dbi] = &cx.outer;
-  rc = mdbx_cursor_put_attr(&cx.outer, key, data ? data : &old_data, attr,
-                            MDBX_CURRENT);
-  txn->tw.cursors[dbi] = cx.outer.mc_next;
-  return rc;
-}
-#endif /* MDBX_NEXENTA_ATTRS */
-
-/******************************************************************************/
-/* *INDENT-OFF* */
-/* clang-format off */
-
-__dll_export
-#ifdef __attribute_used__
-    __attribute_used__
-#elif defined(__GNUC__) || __has_attribute(__used__)
-    __attribute__((__used__))
-#endif
-#ifdef __attribute_externally_visible__
-        __attribute_externally_visible__
-#elif (defined(__GNUC__) && !defined(__clang__)) ||                            \
-    __has_attribute(__externally_visible__)
-    __attribute__((__externally_visible__))
-#endif
-    const struct MDBX_build_info mdbx_build = {
-#ifdef MDBX_BUILD_TIMESTAMP
-    MDBX_BUILD_TIMESTAMP
-#else
-    __DATE__ " " __TIME__
-#endif /* MDBX_BUILD_TIMESTAMP */
-
-    ,
-#ifdef MDBX_BUILD_TARGET
-    MDBX_BUILD_TARGET
-#else
-  #if defined(__ANDROID_API__)
-    "Android" STRINGIFY(__ANDROID_API__)
-  #elif defined(__linux__) || defined(__gnu_linux__)
-    "Linux"
-  #elif defined(EMSCRIPTEN) || defined(__EMSCRIPTEN__)
-    "webassembly"
-  #elif defined(__CYGWIN__)
-    "CYGWIN"
-  #elif defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) \
-      || defined(__WINDOWS__)
-    "Windows"
-  #elif defined(__APPLE__)
-    #if (defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) \
-      || (defined(TARGET_IPHONE_SIMULATOR) && TARGET_IPHONE_SIMULATOR)
-      "iOS"
-    #else
-      "MacOS"
-    #endif
-  #elif defined(__FreeBSD__)
-    "FreeBSD"
-  #elif defined(__DragonFly__)
-    "DragonFlyBSD"
-  #elif defined(__NetBSD__)
-    "NetBSD"
-  #elif defined(__OpenBSD__)
-    "OpenBSD"
-  #elif defined(__bsdi__)
-    "UnixBSDI"
-  #elif defined(__MACH__)
-    "MACH"
-  #elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC))
-    "HPUX"
-  #elif defined(_AIX)
-    "AIX"
-  #elif defined(__sun) && defined(__SVR4)
-    "Solaris"
-  #elif defined(__BSD__) || defined(BSD)
-    "UnixBSD"
-  #elif defined(__unix__) || defined(UNIX) || defined(__unix) \
-      || defined(__UNIX) || defined(__UNIX__)
-    "UNIX"
-  #elif defined(_POSIX_VERSION)
-    "POSIX" STRINGIFY(_POSIX_VERSION)
-  #else
-    "UnknownOS"
-  #endif /* Target OS */
-
-    "-"
-
-  #if defined(__amd64__)
-    "AMD64"
-  #elif defined(__ia32__)
-    "IA32"
-  #elif defined(__e2k__) || defined(__elbrus__)
-    "Elbrus"
-  #elif defined(__alpha__) || defined(__alpha) || defined(_M_ALPHA)
-    "Alpha"
-  #elif defined(__aarch64__) || defined(_M_ARM64)
-    "ARM64"
-  #elif defined(__arm__) || defined(__thumb__) || defined(__TARGET_ARCH_ARM) \
-      || defined(__TARGET_ARCH_THUMB) || defined(_ARM) || defined(_M_ARM) \
-      || defined(_M_ARMT) || defined(__arm)
-    "ARM"
-  #elif defined(__mips64) || defined(__mips64__) || (defined(__mips) && (__mips >= 64))
-    "MIPS64"
-  #elif if defined(__mips__) || defined(__mips) || defined(_R4000) || defined(__MIPS__)
-    "MIPS"
-  #elif defined(__hppa64__) || defined(__HPPA64__) || defined(__hppa64)
-    "PARISC64"
-  #elif defined(__hppa__) || defined(__HPPA__) || defined(__hppa)
-    "PARISC"
-  #elif defined(__ia64__) || defined(__ia64) || defined(_IA64) \
-      || defined(__IA64__) || defined(_M_IA64) || defined(__itanium__)
-    "Itanium"
-  #elif defined(__powerpc64__) || defined(__ppc64__) || defined(__ppc64) \
-      || defined(__powerpc64) || defined(_ARCH_PPC64)
-    "PowerPC64"
-  #elif defined(__powerpc__) || defined(__ppc__) || defined(__powerpc) \
-      || defined(__ppc) || defined(_ARCH_PPC) || defined(__PPC__) || defined(__POWERPC__)
-    "PowerPC"
-  #elif defined(__sparc64__) || defined(__sparc64)
-    "SPARC64"
-  #elif defined(__sparc__) || defined(__sparc)
-    "SPARC"
-  #elif defined(__s390__) || defined(__s390) || defined(__zarch__) || defined(__zarch)
-    "S390"
-  #else
-    "UnknownARCH"
-  #endif
-#endif /* MDBX_BUILD_TARGET */
-
-#ifdef MDBX_BUILD_TYPE
-# if defined(_MSC_VER)
-#   pragma message("Configuration-depended MDBX_BUILD_TYPE: " MDBX_BUILD_TYPE)
-# endif
-    "-" MDBX_BUILD_TYPE
-#endif /* MDBX_BUILD_TYPE */
-    ,
-    "MDBX_DEBUG=" STRINGIFY(MDBX_DEBUG)
-    " MDBX_WORDBITS=" STRINGIFY(MDBX_WORDBITS)
-    " BYTE_ORDER="
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    "LITTLE_ENDIAN"
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    "BIG_ENDIAN"
-#else
-    #error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-    " MDBX_ENV_CHECKPID=" MDBX_ENV_CHECKPID_CONFIG
-    " MDBX_TXN_CHECKOWNER=" MDBX_TXN_CHECKOWNER_CONFIG
-    " MDBX_64BIT_ATOMIC=" MDBX_64BIT_ATOMIC_CONFIG
-    " MDBX_64BIT_CAS=" MDBX_64BIT_CAS_CONFIG
-    " MDBX_TRUST_RTC=" MDBX_TRUST_RTC_CONFIG
-    " MDBX_ENABLE_REFUND=" STRINGIFY(MDBX_ENABLE_REFUND)
-#ifdef __SANITIZE_ADDRESS__
-    " SANITIZE_ADDRESS=YES"
-#endif /* __SANITIZE_ADDRESS__ */
-#ifdef MDBX_USE_VALGRIND
-    " MDBX_USE_VALGRIND=YES"
-#endif /* MDBX_USE_VALGRIND */
-#ifdef MDBX_FORCE_ASSERTIONS
-    " MDBX_FORCE_ASSERTIONS=YES"
-#endif /* MDBX_FORCE_ASSERTIONS */
-#ifdef _GNU_SOURCE
-    " _GNU_SOURCE=YES"
-#else
-    " _GNU_SOURCE=NO"
-#endif /* _GNU_SOURCE */
-#ifdef __APPLE__
-    " MDBX_OSX_SPEED_INSTEADOF_DURABILITY=" STRINGIFY(MDBX_OSX_SPEED_INSTEADOF_DURABILITY)
-#endif /* MacOS */
-#if defined(_WIN32) || defined(_WIN64)
-    " MDBX_AVOID_CRT=" STRINGIFY(MDBX_AVOID_CRT)
-    " MDBX_CONFIG_MANUAL_TLS_CALLBACK=" STRINGIFY(MDBX_CONFIG_MANUAL_TLS_CALLBACK)
-    " MDBX_BUILD_SHARED_LIBRARY=" STRINGIFY(MDBX_BUILD_SHARED_LIBRARY)
-    " WINVER=" STRINGIFY(WINVER)
-#else /* Windows */
-    " MDBX_LOCKING=" MDBX_LOCKING_CONFIG
-    " MDBX_USE_OFDLOCKS=" MDBX_USE_OFDLOCKS_CONFIG
-#endif /* !Windows */
-    " MDBX_CACHELINE_SIZE=" STRINGIFY(MDBX_CACHELINE_SIZE)
-    " MDBX_CPU_WRITEBACK_INCOHERENT=" STRINGIFY(MDBX_CPU_WRITEBACK_INCOHERENT)
-    " MDBX_MMAP_INCOHERENT_CPU_CACHE=" STRINGIFY(MDBX_MMAP_INCOHERENT_CPU_CACHE)
-    " MDBX_MMAP_INCOHERENT_FILE_WRITE=" STRINGIFY(MDBX_MMAP_INCOHERENT_FILE_WRITE)
-    " MDBX_UNALIGNED_OK=" STRINGIFY(MDBX_UNALIGNED_OK)
-    " MDBX_PNL_ASCENDING=" STRINGIFY(MDBX_PNL_ASCENDING)
-    ,
-#ifdef MDBX_BUILD_COMPILER
-    MDBX_BUILD_COMPILER
-#else
-  #ifdef __INTEL_COMPILER
-    "Intel C/C++ " STRINGIFY(__INTEL_COMPILER)
-  #elsif defined(__apple_build_version__)
-    "Apple clang " STRINGIFY(__apple_build_version__)
-  #elif defined(__ibmxl__)
-    "IBM clang C " STRINGIFY(__ibmxl_version__) "." STRINGIFY(__ibmxl_release__)
-    "." STRINGIFY(__ibmxl_modification__) "." STRINGIFY(__ibmxl_ptf_fix_level__)
-  #elif defined(__clang__)
-    "clang " STRINGIFY(__clang_version__)
-  #elif defined(__MINGW64__)
-    "MINGW-64 " STRINGIFY(__MINGW64_MAJOR_VERSION) "." STRINGIFY(__MINGW64_MINOR_VERSION)
-  #elif defined(__MINGW32__)
-    "MINGW-32 " STRINGIFY(__MINGW32_MAJOR_VERSION) "." STRINGIFY(__MINGW32_MINOR_VERSION)
-  #elif defined(__IBMC__)
-    "IBM C " STRINGIFY(__IBMC__)
-  #elif defined(__GNUC__)
-    "GNU C/C++ "
-    #ifdef __VERSION__
-      __VERSION__
-    #else
-      STRINGIFY(__GNUC__) "." STRINGIFY(__GNUC_MINOR__) "." STRINGIFY(__GNUC_PATCHLEVEL__)
-    #endif
-  #elif defined(_MSC_VER)
-    "MSVC " STRINGIFY(_MSC_FULL_VER) "-" STRINGIFY(_MSC_BUILD)
-  #else
-    "Unknown compiler"
-  #endif
-#endif /* MDBX_BUILD_COMPILER */
-    ,
-#ifdef MDBX_BUILD_FLAGS_CONFIG
-    MDBX_BUILD_FLAGS_CONFIG
-#endif /* MDBX_BUILD_FLAGS_CONFIG */
-#ifdef MDBX_BUILD_FLAGS
-    MDBX_BUILD_FLAGS
-#endif /* MDBX_BUILD_FLAGS */
-#if !(defined(MDBX_BUILD_FLAGS_CONFIG) || defined(MDBX_BUILD_FLAGS))
-    "undefined (please use correct build script)"
-#ifdef _MSC_VER
-#pragma message("warning: Build flags undefined. Please use correct build script")
-#else
-#warning "Build flags undefined. Please use correct build script"
-#endif // _MSC_VER
-#endif
-};
-
-#ifdef __SANITIZE_ADDRESS__
-LIBMDBX_API __attribute__((__weak__)) const char *__asan_default_options() {
-  return "symbolize=1:allow_addr2line=1:"
-#ifdef _DEBUG
-         "debug=1:"
-#endif /* _DEBUG */
-         "report_globals=1:"
-         "replace_str=1:replace_intrin=1:"
-         "malloc_context_size=9:"
-         "detect_leaks=1:"
-         "check_printf=1:"
-         "detect_deadlocks=1:"
-#ifndef LTO_ENABLED
-         "check_initialization_order=1:"
-#endif
-         "detect_stack_use_after_return=1:"
-         "intercept_tls_get_addr=1:"
-         "decorate_proc_maps=1:"
-         "abort_on_error=1";
-}
-#endif /* __SANITIZE_ADDRESS__ */
-
-/* *INDENT-ON* */
-/* clang-format on */
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-#if defined(_WIN32) || defined(_WIN64)
-
-#include <winioctl.h>
-
-static int waitstatus2errcode(DWORD result) {
-  switch (result) {
-  case WAIT_OBJECT_0:
-    return MDBX_SUCCESS;
-  case WAIT_FAILED:
-    return GetLastError();
-  case WAIT_ABANDONED:
-    return ERROR_ABANDONED_WAIT_0;
-  case WAIT_IO_COMPLETION:
-    return ERROR_USER_APC;
-  case WAIT_TIMEOUT:
-    return ERROR_TIMEOUT;
-  default:
-    return ERROR_UNHANDLED_ERROR;
-  }
-}
-
-/* Map a result from an NTAPI call to WIN32 error code. */
-static int ntstatus2errcode(NTSTATUS status) {
-  DWORD dummy;
-  OVERLAPPED ov;
-  memset(&ov, 0, sizeof(ov));
-  ov.Internal = status;
-  return GetOverlappedResult(NULL, &ov, &dummy, FALSE) ? MDBX_SUCCESS
-                                                       : GetLastError();
-}
-
-/* We use native NT APIs to setup the memory map, so that we can
- * let the DB file grow incrementally instead of always preallocating
- * the full size. These APIs are defined in <wdm.h> and <ntifs.h>
- * but those headers are meant for driver-level development and
- * conflict with the regular user-level headers, so we explicitly
- * declare them here. Using these APIs also means we must link to
- * ntdll.dll, which is not linked by default in user code. */
-
-extern NTSTATUS NTAPI NtCreateSection(
-    OUT PHANDLE SectionHandle, IN ACCESS_MASK DesiredAccess,
-    IN OPTIONAL POBJECT_ATTRIBUTES ObjectAttributes,
-    IN OPTIONAL PLARGE_INTEGER MaximumSize, IN ULONG SectionPageProtection,
-    IN ULONG AllocationAttributes, IN OPTIONAL HANDLE FileHandle);
-
-typedef struct _SECTION_BASIC_INFORMATION {
-  ULONG Unknown;
-  ULONG SectionAttributes;
-  LARGE_INTEGER SectionSize;
-} SECTION_BASIC_INFORMATION, *PSECTION_BASIC_INFORMATION;
-
-extern NTSTATUS NTAPI NtMapViewOfSection(
-    IN HANDLE SectionHandle, IN HANDLE ProcessHandle, IN OUT PVOID *BaseAddress,
-    IN ULONG_PTR ZeroBits, IN SIZE_T CommitSize,
-    IN OUT OPTIONAL PLARGE_INTEGER SectionOffset, IN OUT PSIZE_T ViewSize,
-    IN SECTION_INHERIT InheritDisposition, IN ULONG AllocationType,
-    IN ULONG Win32Protect);
-
-extern NTSTATUS NTAPI NtUnmapViewOfSection(IN HANDLE ProcessHandle,
-                                           IN OPTIONAL PVOID BaseAddress);
-
-extern NTSTATUS NTAPI NtClose(HANDLE Handle);
-
-extern NTSTATUS NTAPI NtAllocateVirtualMemory(
-    IN HANDLE ProcessHandle, IN OUT PVOID *BaseAddress, IN ULONG_PTR ZeroBits,
-    IN OUT PSIZE_T RegionSize, IN ULONG AllocationType, IN ULONG Protect);
-
-extern NTSTATUS NTAPI NtFreeVirtualMemory(IN HANDLE ProcessHandle,
-                                          IN PVOID *BaseAddress,
-                                          IN OUT PSIZE_T RegionSize,
-                                          IN ULONG FreeType);
-
-#ifndef WOF_CURRENT_VERSION
-typedef struct _WOF_EXTERNAL_INFO {
-  DWORD Version;
-  DWORD Provider;
-} WOF_EXTERNAL_INFO, *PWOF_EXTERNAL_INFO;
-#endif /* WOF_CURRENT_VERSION */
-
-#ifndef WIM_PROVIDER_CURRENT_VERSION
-#define WIM_PROVIDER_HASH_SIZE 20
-
-typedef struct _WIM_PROVIDER_EXTERNAL_INFO {
-  DWORD Version;
-  DWORD Flags;
-  LARGE_INTEGER DataSourceId;
-  BYTE ResourceHash[WIM_PROVIDER_HASH_SIZE];
-} WIM_PROVIDER_EXTERNAL_INFO, *PWIM_PROVIDER_EXTERNAL_INFO;
-#endif /* WIM_PROVIDER_CURRENT_VERSION */
-
-#ifndef FILE_PROVIDER_CURRENT_VERSION
-typedef struct _FILE_PROVIDER_EXTERNAL_INFO_V1 {
-  ULONG Version;
-  ULONG Algorithm;
-  ULONG Flags;
-} FILE_PROVIDER_EXTERNAL_INFO_V1, *PFILE_PROVIDER_EXTERNAL_INFO_V1;
-#endif /* FILE_PROVIDER_CURRENT_VERSION */
-
-#ifndef STATUS_OBJECT_NOT_EXTERNALLY_BACKED
-#define STATUS_OBJECT_NOT_EXTERNALLY_BACKED ((NTSTATUS)0xC000046DL)
-#endif
-#ifndef STATUS_INVALID_DEVICE_REQUEST
-#define STATUS_INVALID_DEVICE_REQUEST ((NTSTATUS)0xC0000010L)
-#endif
-#ifndef STATUS_NOT_SUPPORTED
-#define STATUS_NOT_SUPPORTED ((NTSTATUS)0xC00000BBL)
-#endif
-
-#ifndef FILE_DEVICE_FILE_SYSTEM
-#define FILE_DEVICE_FILE_SYSTEM 0x00000009
-#endif
-
-#ifndef FSCTL_GET_EXTERNAL_BACKING
-#define FSCTL_GET_EXTERNAL_BACKING                                             \
-  CTL_CODE(FILE_DEVICE_FILE_SYSTEM, 196, METHOD_BUFFERED, FILE_ANY_ACCESS)
-#endif
-
-#endif /* _WIN32 || _WIN64 */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(__UCLIBC__)
-__extern_C void __assert(const char *, const char *, unsigned int, const char *)
-#ifdef __THROW
-    __THROW
-#else
-    __nothrow
-#endif /* __THROW */
-    MDBX_NORETURN;
-#define __assert_fail(assertion, file, line, function)                         \
-  __assert(assertion, file, line, function)
-
-#elif _POSIX_C_SOURCE > 200212 &&                                              \
-    /* workaround for avoid musl libc wrong prototype */ (                     \
-        defined(__GLIBC__) || defined(__GNU_LIBRARY__))
-/* Prototype should match libc runtime. ISO POSIX (2003) & LSB 1.x-3.x */
-__extern_C void __assert_fail(const char *assertion, const char *file,
-                              unsigned line, const char *function)
-#ifdef __THROW
-    __THROW
-#else
-    __nothrow
-#endif /* __THROW */
-    MDBX_NORETURN;
-
-#elif defined(__APPLE__) || defined(__MACH__)
-__extern_C void __assert_rtn(const char *function, const char *file, int line,
-                             const char *assertion) /* __nothrow */
-#ifdef __dead2
-    __dead2
-#else
-    MDBX_NORETURN
-#endif /* __dead2 */
-#ifdef __disable_tail_calls
-    __disable_tail_calls
-#endif /* __disable_tail_calls */
-    ;
-
-#define __assert_fail(assertion, file, line, function)                         \
-  __assert_rtn(function, file, line, assertion)
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-__extern_C void __assert_c99(const char *assection, const char *file, int line,
-                             const char *function) MDBX_NORETURN;
-#define __assert_fail(assertion, file, line, function)                         \
-  __assert_c99(assertion, file, line, function)
-#elif defined(__OpenBSD__)
-__extern_C __dead void __assert2(const char *file, int line,
-                                 const char *function,
-                                 const char *assertion) /* __nothrow */;
-#define __assert_fail(assertion, file, line, function)                         \
-  __assert2(file, line, function, assertion)
-#elif defined(__NetBSD__)
-__extern_C __dead void __assert13(const char *file, int line,
-                                  const char *function,
-                                  const char *assertion) /* __nothrow */;
-#define __assert_fail(assertion, file, line, function)                         \
-  __assert13(file, line, function, assertion)
-#elif defined(__FreeBSD__) || defined(__BSD__) || defined(__bsdi__) ||         \
-    defined(__DragonFly__)
-__extern_C void __assert(const char *function, const char *file, int line,
-                         const char *assertion) /* __nothrow */
-#ifdef __dead2
-    __dead2
-#else
-    MDBX_NORETURN
-#endif /* __dead2 */
-#ifdef __disable_tail_calls
-    __disable_tail_calls
-#endif /* __disable_tail_calls */
-    ;
-#define __assert_fail(assertion, file, line, function)                         \
-  __assert(function, file, line, assertion)
-
-#endif /* __assert_fail */
-
-#if !defined(__ANDROID_API__) || MDBX_DEBUG
-
-void __cold mdbx_assert_fail(const MDBX_env *env, const char *msg,
-                             const char *func, int line) {
-#if MDBX_DEBUG
-  if (env && env->me_assert_func) {
-    env->me_assert_func(env, msg, func, line);
-    return;
-  }
-#else
-  (void)env;
-#endif /* MDBX_DEBUG */
-
-  if (mdbx_debug_logger)
-    mdbx_debug_log(MDBX_LOG_FATAL, func, line, "assert: %s\n", msg);
-  else {
-#if defined(_WIN32) || defined(_WIN64)
-    char *message = nullptr;
-    const int num = mdbx_asprintf(&message, "\r\nMDBX-ASSERTION: %s, %s:%u",
-                                  msg, func ? func : "unknown", line);
-    if (num < 1 || !message)
-      message = "<troubles with assertion-message preparation>";
-    OutputDebugStringA(message);
-    if (IsDebuggerPresent())
-      DebugBreak();
-#elif defined(__ANDROID_API__)
-    __android_log_assert(msg, "mdbx", "%s:%u", func, line);
-#else
-    __assert_fail(msg, "mdbx", line, func);
-#endif
-  }
-
-#if defined(_WIN32) || defined(_WIN64)
-  FatalExit(ERROR_UNHANDLED_ERROR);
-#else
-  abort();
-#endif
-}
-
-#endif /* __ANDROID_API__ || MDBX_DEBUG */
-
-__cold void mdbx_panic(const char *fmt, ...) {
-  va_list ap;
-  va_start(ap, fmt);
-
-  char *message = nullptr;
-  const int num = mdbx_vasprintf(&message, fmt, ap);
-  va_end(ap);
-  const char *const const_message =
-      (num < 1 || !message) ? "<troubles with panic-message preparation>"
-                            : message;
-
-#if defined(_WIN32) || defined(_WIN64)
-  OutputDebugStringA("\r\nMDBX-PANIC: ");
-  OutputDebugStringA(const_message);
-  if (IsDebuggerPresent())
-    DebugBreak();
-  FatalExit(ERROR_UNHANDLED_ERROR);
-#else
-#if defined(__ANDROID_API__)
-  __android_log_assert("panic", "mdbx", "%s", const_message);
-#else
-  __assert_fail(const_message, "mdbx", 0, "panic");
-#endif /* __ANDROID_API__ */
-  abort();
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef mdbx_vasprintf
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt,
-                                      va_list ap) {
-  va_list ones;
-  va_copy(ones, ap);
-  int needed = vsnprintf(nullptr, 0, fmt, ap);
-
-  if (unlikely(needed < 0 || needed >= INT_MAX)) {
-    *strp = nullptr;
-    va_end(ones);
-    return needed;
-  }
-
-  *strp = mdbx_malloc(needed + 1);
-  if (unlikely(*strp == nullptr)) {
-    va_end(ones);
-#if defined(_WIN32) || defined(_WIN64)
-    SetLastError(MDBX_ENOMEM);
-#else
-    errno = MDBX_ENOMEM;
-#endif
-    return -1;
-  }
-
-  int actual = vsnprintf(*strp, needed + 1, fmt, ones);
-  va_end(ones);
-
-  assert(actual == needed);
-  if (unlikely(actual < 0)) {
-    mdbx_free(*strp);
-    *strp = nullptr;
-  }
-  return actual;
-}
-#endif /* mdbx_vasprintf */
-
-#ifndef mdbx_asprintf
-MDBX_INTERNAL_FUNC int mdbx_asprintf(char **strp, const char *fmt, ...) {
-  va_list ap;
-  va_start(ap, fmt);
-  int rc = mdbx_vasprintf(strp, fmt, ap);
-  va_end(ap);
-  return rc;
-}
-#endif /* mdbx_asprintf */
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result) {
-  assert(is_powerof2(alignment) && alignment >= sizeof(void *));
-#if defined(_WIN32) || defined(_WIN64)
-  (void)alignment;
-  *result = VirtualAlloc(NULL, bytes, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
-  return *result ? MDBX_SUCCESS : MDBX_ENOMEM /* ERROR_OUTOFMEMORY */;
-#elif defined(_ISOC11_SOURCE)
-  *result = aligned_alloc(alignment, ceil_powerof2(bytes, alignment));
-  return *result ? MDBX_SUCCESS : errno;
-#elif _POSIX_VERSION >= 200112L &&                                             \
-    (!defined(__ANDROID_API__) || __ANDROID_API__ >= 17)
-  *result = nullptr;
-  return posix_memalign(result, alignment, bytes);
-#elif __GLIBC_PREREQ(2, 16) || __STDC_VERSION__ >= 201112L
-  *result = memalign(alignment, bytes);
-  return *result ? MDBX_SUCCESS : errno;
-#else
-#error FIXME
-#endif
-}
-#endif /* mdbx_memalign_alloc */
-
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr) {
-#if defined(_WIN32) || defined(_WIN64)
-  VirtualFree(ptr, 0, MEM_RELEASE);
-#else
-  mdbx_free(ptr);
-#endif
-}
-#endif /* mdbx_memalign_free */
-
-#ifndef mdbx_strdup
-char *mdbx_strdup(const char *str) {
-  if (!str)
-    return NULL;
-  size_t bytes = strlen(str) + 1;
-  char *dup = mdbx_malloc(bytes);
-  if (dup)
-    memcpy(dup, str, bytes);
-  return dup;
-}
-#endif /* mdbx_strdup */
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair) {
-  int rc;
-  memset(condpair, 0, sizeof(mdbx_condpair_t));
-#if defined(_WIN32) || defined(_WIN64)
-  if ((condpair->mutex = CreateMutexW(NULL, FALSE, NULL)) == NULL) {
-    rc = GetLastError();
-    goto bailout_mutex;
-  }
-  if ((condpair->event[0] = CreateEventW(NULL, FALSE, FALSE, NULL)) == NULL) {
-    rc = GetLastError();
-    goto bailout_event;
-  }
-  if ((condpair->event[1] = CreateEventW(NULL, FALSE, FALSE, NULL)) != NULL)
-    return MDBX_SUCCESS;
-
-  rc = GetLastError();
-  (void)CloseHandle(condpair->event[0]);
-bailout_event:
-  (void)CloseHandle(condpair->mutex);
-#else
-  rc = pthread_mutex_init(&condpair->mutex, NULL);
-  if (unlikely(rc != 0))
-    goto bailout_mutex;
-  rc = pthread_cond_init(&condpair->cond[0], NULL);
-  if (unlikely(rc != 0))
-    goto bailout_cond;
-  rc = pthread_cond_init(&condpair->cond[1], NULL);
-  if (likely(rc == 0))
-    return MDBX_SUCCESS;
-
-  (void)pthread_cond_destroy(&condpair->cond[0]);
-bailout_cond:
-  (void)pthread_mutex_destroy(&condpair->mutex);
-#endif
-bailout_mutex:
-  memset(condpair, 0, sizeof(mdbx_condpair_t));
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair) {
-#if defined(_WIN32) || defined(_WIN64)
-  int rc = CloseHandle(condpair->mutex) ? MDBX_SUCCESS : GetLastError();
-  rc = CloseHandle(condpair->event[0]) ? rc : GetLastError();
-  rc = CloseHandle(condpair->event[1]) ? rc : GetLastError();
-#else
-  int err, rc = pthread_mutex_destroy(&condpair->mutex);
-  rc = (err = pthread_cond_destroy(&condpair->cond[0])) ? err : rc;
-  rc = (err = pthread_cond_destroy(&condpair->cond[1])) ? err : rc;
-#endif
-  memset(condpair, 0, sizeof(mdbx_condpair_t));
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD code = WaitForSingleObject(condpair->mutex, INFINITE);
-  return waitstatus2errcode(code);
-#else
-  return pthread_mutex_lock(&condpair->mutex);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair) {
-#if defined(_WIN32) || defined(_WIN64)
-  return ReleaseMutex(condpair->mutex) ? MDBX_SUCCESS : GetLastError();
-#else
-  return pthread_mutex_unlock(&condpair->mutex);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part) {
-#if defined(_WIN32) || defined(_WIN64)
-  return SetEvent(condpair->event[part]) ? MDBX_SUCCESS : GetLastError();
-#else
-  return pthread_cond_signal(&condpair->cond[part]);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair,
-                                          bool part) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD code = SignalObjectAndWait(condpair->mutex, condpair->event[part],
-                                   INFINITE, FALSE);
-  if (code == WAIT_OBJECT_0) {
-    code = WaitForSingleObject(condpair->mutex, INFINITE);
-    if (code == WAIT_OBJECT_0)
-      return MDBX_SUCCESS;
-  }
-  return waitstatus2errcode(code);
-#else
-  return pthread_cond_wait(&condpair->cond[part], &condpair->mutex);
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex) {
-#if defined(_WIN32) || defined(_WIN64)
-  InitializeCriticalSection(fastmutex);
-  return MDBX_SUCCESS;
-#else
-  return pthread_mutex_init(fastmutex, NULL);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex) {
-#if defined(_WIN32) || defined(_WIN64)
-  DeleteCriticalSection(fastmutex);
-  return MDBX_SUCCESS;
-#else
-  return pthread_mutex_destroy(fastmutex);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex) {
-#if defined(_WIN32) || defined(_WIN64)
-  __try {
-    EnterCriticalSection(fastmutex);
-  } __except (
-      (GetExceptionCode() ==
-       0xC0000194 /* STATUS_POSSIBLE_DEADLOCK / EXCEPTION_POSSIBLE_DEADLOCK */)
-          ? EXCEPTION_EXECUTE_HANDLER
-          : EXCEPTION_CONTINUE_SEARCH) {
-    return ERROR_POSSIBLE_DEADLOCK;
-  }
-  return MDBX_SUCCESS;
-#else
-  return pthread_mutex_lock(fastmutex);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex) {
-#if defined(_WIN32) || defined(_WIN64)
-  LeaveCriticalSection(fastmutex);
-  return MDBX_SUCCESS;
-#else
-  return pthread_mutex_unlock(fastmutex);
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname) {
-#if defined(_WIN32) || defined(_WIN64)
-  const size_t wlen = mbstowcs(nullptr, pathname, INT_MAX);
-  if (wlen < 1 || wlen > /* MAX_PATH */ INT16_MAX)
-    return ERROR_INVALID_NAME;
-  wchar_t *const pathnameW = _alloca((wlen + 1) * sizeof(wchar_t));
-  if (wlen != mbstowcs(pathnameW, pathname, wlen + 1))
-    return ERROR_INVALID_NAME;
-  return DeleteFileW(pathnameW) ? MDBX_SUCCESS : GetLastError();
-#else
-  return unlink(pathname) ? errno : MDBX_SUCCESS;
-#endif
-}
-
-#if !(defined(_WIN32) || defined(_WIN64))
-static bool is_valid_fd(int fd) { return !(isatty(fd) < 0 && errno == EBADF); }
-#endif /*! Windows */
-
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname) {
-#if defined(_WIN32) || defined(_WIN64)
-  const size_t wlen = mbstowcs(nullptr, pathname, INT_MAX);
-  if (wlen < 1 || wlen > /* MAX_PATH */ INT16_MAX)
-    return ERROR_INVALID_NAME;
-  wchar_t *const pathnameW = _alloca((wlen + 1) * sizeof(wchar_t));
-  if (wlen != mbstowcs(pathnameW, pathname, wlen + 1))
-    return ERROR_INVALID_NAME;
-  return RemoveDirectoryW(pathnameW) ? MDBX_SUCCESS : GetLastError();
-#else
-  return rmdir(pathname) ? errno : MDBX_SUCCESS;
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits) {
-  *fd = INVALID_HANDLE_VALUE;
-
-#if defined(_WIN32) || defined(_WIN64)
-  const size_t wlen = mbstowcs(nullptr, pathname, INT_MAX);
-  if (wlen < 1 || wlen > /* MAX_PATH */ INT16_MAX)
-    return ERROR_INVALID_NAME;
-  wchar_t *const pathnameW = _alloca((wlen + 1) * sizeof(wchar_t));
-  if (wlen != mbstowcs(pathnameW, pathname, wlen + 1))
-    return ERROR_INVALID_NAME;
-
-  DWORD CreationDisposition = unix_mode_bits ? OPEN_ALWAYS : OPEN_EXISTING;
-  DWORD FlagsAndAttributes =
-      FILE_FLAG_POSIX_SEMANTICS | FILE_ATTRIBUTE_NOT_CONTENT_INDEXED;
-  DWORD DesiredAccess = FILE_READ_ATTRIBUTES;
-  DWORD ShareMode = (env->me_flags & MDBX_EXCLUSIVE)
-                        ? 0
-                        : (FILE_SHARE_READ | FILE_SHARE_WRITE);
-
-  switch (purpose) {
-  default:
-    return ERROR_INVALID_PARAMETER;
-  case MDBX_OPEN_LCK:
-    CreationDisposition = OPEN_ALWAYS;
-    DesiredAccess |= GENERIC_READ | GENERIC_WRITE;
-    FlagsAndAttributes |= FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_TEMPORARY;
-    break;
-  case MDBX_OPEN_DXB_READ:
-    CreationDisposition = OPEN_EXISTING;
-    DesiredAccess |= GENERIC_READ;
-    ShareMode |= FILE_SHARE_READ;
-    break;
-  case MDBX_OPEN_DXB_LAZY:
-    DesiredAccess |= GENERIC_READ | GENERIC_WRITE;
-    break;
-  case MDBX_OPEN_DXB_DSYNC:
-    CreationDisposition = OPEN_EXISTING;
-    DesiredAccess |= GENERIC_WRITE;
-    FlagsAndAttributes |= FILE_FLAG_WRITE_THROUGH;
-    break;
-  case MDBX_OPEN_COPY:
-    CreationDisposition = CREATE_NEW;
-    ShareMode = 0;
-    DesiredAccess |= GENERIC_WRITE;
-    FlagsAndAttributes |=
-        (env->me_psize < env->me_os_psize) ? 0 : FILE_FLAG_NO_BUFFERING;
-    break;
-  case MDBX_OPEN_DELETE:
-    CreationDisposition = OPEN_EXISTING;
-    ShareMode |= FILE_SHARE_DELETE;
-    DesiredAccess =
-        FILE_READ_ATTRIBUTES | FILE_WRITE_ATTRIBUTES | DELETE | SYNCHRONIZE;
-    break;
-  }
-
-  *fd = CreateFileW(pathnameW, DesiredAccess, ShareMode, NULL,
-                    CreationDisposition, FlagsAndAttributes, NULL);
-  if (*fd == INVALID_HANDLE_VALUE)
-    return GetLastError();
-
-  BY_HANDLE_FILE_INFORMATION info;
-  if (!GetFileInformationByHandle(*fd, &info)) {
-    int err = GetLastError();
-    CloseHandle(*fd);
-    *fd = INVALID_HANDLE_VALUE;
-    return err;
-  }
-  const DWORD AttributesDiff =
-      (info.dwFileAttributes ^ FlagsAndAttributes) &
-      (FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_NOT_CONTENT_INDEXED |
-       FILE_ATTRIBUTE_TEMPORARY | FILE_ATTRIBUTE_COMPRESSED);
-  if (AttributesDiff)
-    (void)SetFileAttributesW(pathnameW, info.dwFileAttributes ^ AttributesDiff);
-
-#else
-  int flags = unix_mode_bits ? O_CREAT : 0;
-  switch (purpose) {
-  default:
-    return EINVAL;
-  case MDBX_OPEN_LCK:
-    flags |= O_RDWR;
-    break;
-  case MDBX_OPEN_DXB_READ:
-    flags = O_RDONLY;
-    break;
-  case MDBX_OPEN_DXB_LAZY:
-    flags |= O_RDWR;
-    break;
-  case MDBX_OPEN_COPY:
-    flags = O_CREAT | O_WRONLY | O_EXCL;
-    break;
-  case MDBX_OPEN_DXB_DSYNC:
-    flags |= O_WRONLY;
-#if defined(O_DSYNC)
-    flags |= O_DSYNC;
-#elif defined(O_SYNC)
-    flags |= O_SYNC;
-#elif defined(O_FSYNC)
-    flags |= O_FSYNC;
-#endif
-    break;
-  case MDBX_OPEN_DELETE:
-    flags = O_RDWR;
-    break;
-  }
-
-  const bool direct_nocache_for_copy =
-      env->me_psize >= env->me_os_psize && purpose == MDBX_OPEN_COPY;
-  if (direct_nocache_for_copy) {
-#if defined(O_DIRECT)
-    flags |= O_DIRECT;
-#endif /* O_DIRECT */
-#if defined(O_NOCACHE)
-    flags |= O_NOCACHE;
-#endif /* O_NOCACHE */
-  }
-
-#ifdef O_CLOEXEC
-  flags |= O_CLOEXEC;
-#endif /* O_CLOEXEC */
-
-  /* Safeguard for https://github.com/erthink/libmdbx/issues/144 */
-#if STDIN_FILENO == 0 && STDOUT_FILENO == 1 && STDERR_FILENO == 2
-  int stub_fd0 = -1, stub_fd1 = -1, stub_fd2 = -1;
-  static const char dev_null[] = "/dev/null";
-  if (!is_valid_fd(STDIN_FILENO)) {
-    mdbx_warning("STD%s_FILENO/%d is invalid, open %s for temporary stub", "IN",
-                 STDIN_FILENO, dev_null);
-    stub_fd0 = open(dev_null, O_RDONLY | O_NOCTTY);
-  }
-  if (!is_valid_fd(STDOUT_FILENO)) {
-    mdbx_warning("STD%s_FILENO/%d is invalid, open %s for temporary stub",
-                 "OUT", STDOUT_FILENO, dev_null);
-    stub_fd1 = open(dev_null, O_WRONLY | O_NOCTTY);
-  }
-  if (!is_valid_fd(STDERR_FILENO)) {
-    mdbx_warning("STD%s_FILENO/%d is invalid, open %s for temporary stub",
-                 "ERR", STDERR_FILENO, dev_null);
-    stub_fd2 = open(dev_null, O_WRONLY | O_NOCTTY);
-  }
-#else
-#error "Unexpected or unsupported UNIX or POSIX system"
-#endif /* STDIN_FILENO == 0 && STDERR_FILENO == 2 */
-
-  *fd = open(pathname, flags, unix_mode_bits);
-#if defined(O_DIRECT)
-  if (*fd < 0 && (flags & O_DIRECT) &&
-      (errno == EINVAL || errno == EAFNOSUPPORT)) {
-    flags &= ~(O_DIRECT | O_EXCL);
-    *fd = open(pathname, flags, unix_mode_bits);
-  }
-#endif /* O_DIRECT */
-
-  /* Safeguard for https://github.com/erthink/libmdbx/issues/144 */
-#if STDIN_FILENO == 0 && STDOUT_FILENO == 1 && STDERR_FILENO == 2
-  if (*fd == STDIN_FILENO) {
-    mdbx_warning("Got STD%s_FILENO/%d, avoid using it by dup(fd)", "IN",
-                 STDIN_FILENO);
-    assert(stub_fd0 == -1);
-    *fd = dup(stub_fd0 = *fd);
-  }
-  if (*fd == STDOUT_FILENO) {
-    mdbx_warning("Got STD%s_FILENO/%d, avoid using it by dup(fd)", "OUT",
-                 STDOUT_FILENO);
-    assert(stub_fd1 == -1);
-    *fd = dup(stub_fd1 = *fd);
-  }
-  if (*fd == STDERR_FILENO) {
-    mdbx_warning("Got STD%s_FILENO/%d, avoid using it by dup(fd)", "ERR",
-                 STDERR_FILENO);
-    assert(stub_fd2 == -1);
-    *fd = dup(stub_fd2 = *fd);
-  }
-  if (stub_fd0 != -1)
-    close(stub_fd0);
-  if (stub_fd1 != -1)
-    close(stub_fd1);
-  if (stub_fd2 != -1)
-    close(stub_fd2);
-  if (*fd >= STDIN_FILENO && *fd <= STDERR_FILENO) {
-    mdbx_error(
-        "Rejecting the use of a FD in the range "
-        "STDIN_FILENO/%d..STDERR_FILENO/%d to prevent database corruption",
-        STDIN_FILENO, STDERR_FILENO);
-    close(*fd);
-    return EBADF;
-  }
-#else
-#error "Unexpected or unsupported UNIX or POSIX system"
-#endif /* STDIN_FILENO == 0 && STDERR_FILENO == 2 */
-
-  if (*fd < 0)
-    return errno;
-
-#if defined(FD_CLOEXEC) && !defined(O_CLOEXEC)
-  const int fd_flags = fcntl(*fd, F_GETFD);
-  if (fd_flags != -1)
-    (void)fcntl(*fd, F_SETFD, fd_flags | FD_CLOEXEC);
-#endif /* FD_CLOEXEC && !O_CLOEXEC */
-
-  if (direct_nocache_for_copy) {
-#if defined(F_NOCACHE) && !defined(O_NOCACHE)
-    (void)fcntl(*fd, F_NOCACHE, 1);
-#endif /* F_NOCACHE */
-  }
-
-#endif
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd) {
-#if defined(_WIN32) || defined(_WIN64)
-  return CloseHandle(fd) ? MDBX_SUCCESS : GetLastError();
-#else
-  assert(fd > STDERR_FILENO);
-  return (close(fd) == 0) ? MDBX_SUCCESS : errno;
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t bytes,
-                                  uint64_t offset) {
-  if (bytes > MAX_WRITE)
-    return MDBX_EINVAL;
-#if defined(_WIN32) || defined(_WIN64)
-  OVERLAPPED ov;
-  ov.hEvent = 0;
-  ov.Offset = (DWORD)offset;
-  ov.OffsetHigh = HIGH_DWORD(offset);
-
-  DWORD read = 0;
-  if (unlikely(!ReadFile(fd, buf, (DWORD)bytes, &read, &ov))) {
-    int rc = GetLastError();
-    return (rc == MDBX_SUCCESS) ? /* paranoia */ ERROR_READ_FAULT : rc;
-  }
-#else
-  STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
-                    "libmdbx requires 64-bit file I/O on 64-bit systems");
-  intptr_t read = pread(fd, buf, bytes, offset);
-  if (read < 0) {
-    int rc = errno;
-    return (rc == MDBX_SUCCESS) ? /* paranoia */ MDBX_EIO : rc;
-  }
-#endif
-  return (bytes == (size_t)read) ? MDBX_SUCCESS : MDBX_ENODATA;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t bytes, uint64_t offset) {
-  while (true) {
-#if defined(_WIN32) || defined(_WIN64)
-    OVERLAPPED ov;
-    ov.hEvent = 0;
-    ov.Offset = (DWORD)offset;
-    ov.OffsetHigh = HIGH_DWORD(offset);
-
-    DWORD written;
-    if (unlikely(!WriteFile(
-            fd, buf, likely(bytes <= MAX_WRITE) ? (DWORD)bytes : MAX_WRITE,
-            &written, &ov)))
-      return GetLastError();
-    if (likely(bytes == written))
-      return MDBX_SUCCESS;
-#else
-    STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
-                      "libmdbx requires 64-bit file I/O on 64-bit systems");
-    const intptr_t written =
-        pwrite(fd, buf, likely(bytes <= MAX_WRITE) ? bytes : MAX_WRITE, offset);
-    if (likely(bytes == (size_t)written))
-      return MDBX_SUCCESS;
-    if (written < 0) {
-      const int rc = errno;
-      if (rc != EINTR)
-        return rc;
-      continue;
-    }
-#endif
-    bytes -= written;
-    offset += written;
-    buf = (char *)buf + written;
-  }
-}
-
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t bytes) {
-  while (true) {
-#if defined(_WIN32) || defined(_WIN64)
-    DWORD written;
-    if (unlikely(!WriteFile(
-            fd, buf, likely(bytes <= MAX_WRITE) ? (DWORD)bytes : MAX_WRITE,
-            &written, nullptr)))
-      return GetLastError();
-    if (likely(bytes == written))
-      return MDBX_SUCCESS;
-#else
-    STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
-                      "libmdbx requires 64-bit file I/O on 64-bit systems");
-    const intptr_t written =
-        write(fd, buf, likely(bytes <= MAX_WRITE) ? bytes : MAX_WRITE);
-    if (likely(bytes == (size_t)written))
-      return MDBX_SUCCESS;
-    if (written < 0) {
-      const int rc = errno;
-      if (rc != EINTR)
-        return rc;
-      continue;
-    }
-#endif
-    bytes -= written;
-    buf = (char *)buf + written;
-  }
-}
-
-int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov, int iovcnt,
-                 uint64_t offset, size_t expected_written) {
-#if defined(_WIN32) || defined(_WIN64) || defined(__APPLE__) ||                \
-    (defined(__ANDROID_API__) && __ANDROID_API__ < 24)
-  size_t written = 0;
-  for (int i = 0; i < iovcnt; ++i) {
-    int rc = mdbx_pwrite(fd, iov[i].iov_base, iov[i].iov_len, offset);
-    if (unlikely(rc != MDBX_SUCCESS))
-      return rc;
-    written += iov[i].iov_len;
-    offset += iov[i].iov_len;
-  }
-  return (expected_written == written) ? MDBX_SUCCESS
-                                       : MDBX_EIO /* ERROR_WRITE_FAULT */;
-#else
-  int rc;
-  intptr_t written;
-  do {
-    STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
-                      "libmdbx requires 64-bit file I/O on 64-bit systems");
-    written = pwritev(fd, iov, iovcnt, offset);
-    if (likely(expected_written == (size_t)written))
-      return MDBX_SUCCESS;
-    rc = errno;
-  } while (rc == EINTR);
-  return (written < 0) ? rc : MDBX_EIO /* Use which error code? */;
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  enum mdbx_syncmode_bits mode_bits) {
-#if defined(_WIN32) || defined(_WIN64)
-  if ((mode_bits & (MDBX_SYNC_DATA | MDBX_SYNC_IODQ)) && !FlushFileBuffers(fd))
-    return GetLastError();
-  return MDBX_SUCCESS;
-#else
-
-#if defined(__APPLE__) &&                                                      \
-    MDBX_OSX_SPEED_INSTEADOF_DURABILITY == MDBX_OSX_WANNA_DURABILITY
-  if (mode_bits & MDBX_SYNC_IODQ)
-    return likely(fcntl(fd, F_FULLFSYNC) != -1) ? MDBX_SUCCESS : errno;
-#endif /* MacOS */
-
-  /* LY: This approach is always safe and without appreciable performance
-   * degradation, even on a kernel with fdatasync's bug.
-   *
-   * For more info about of a corresponding fdatasync() bug
-   * see http://www.spinics.net/lists/linux-ext4/msg33714.html */
-  while (1) {
-    switch (mode_bits & (MDBX_SYNC_DATA | MDBX_SYNC_SIZE)) {
-    case MDBX_SYNC_NONE:
-      return MDBX_SUCCESS /* nothing to do */;
-#if defined(_POSIX_SYNCHRONIZED_IO) && _POSIX_SYNCHRONIZED_IO > 0
-    case MDBX_SYNC_DATA:
-      if (fdatasync(fd) == 0)
-        return MDBX_SUCCESS;
-      break /* error */;
-#if defined(__linux__) || defined(__gnu_linux__)
-    case MDBX_SYNC_SIZE:
-      if (mdbx_linux_kernel_version >= 0x03060000)
-        return MDBX_SUCCESS;
-      __fallthrough /* fall through */;
-#endif /* Linux */
-#endif /* _POSIX_SYNCHRONIZED_IO > 0 */
-    default:
-      if (fsync(fd) == 0)
-        return MDBX_SUCCESS;
-    }
-
-    int rc = errno;
-    if (rc != EINTR)
-      return rc;
-  }
-#endif
-}
-
-int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length) {
-#if defined(_WIN32) || defined(_WIN64)
-  BY_HANDLE_FILE_INFORMATION info;
-  if (!GetFileInformationByHandle(fd, &info))
-    return GetLastError();
-  *length = info.nFileSizeLow | (uint64_t)info.nFileSizeHigh << 32;
-#else
-  struct stat st;
-
-  STATIC_ASSERT_MSG(sizeof(off_t) <= sizeof(uint64_t),
-                    "libmdbx requires 64-bit file I/O on 64-bit systems");
-  if (fstat(fd, &st))
-    return errno;
-
-  *length = st.st_size;
-#endif
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd) {
-#if defined(_WIN32) || defined(_WIN64)
-  switch (GetFileType(fd)) {
-  case FILE_TYPE_DISK:
-    return MDBX_RESULT_FALSE;
-  case FILE_TYPE_CHAR:
-  case FILE_TYPE_PIPE:
-    return MDBX_RESULT_TRUE;
-  default:
-    return GetLastError();
-  }
-#else
-  struct stat info;
-  if (fstat(fd, &info))
-    return errno;
-  switch (info.st_mode & S_IFMT) {
-  case S_IFBLK:
-  case S_IFREG:
-    return MDBX_RESULT_FALSE;
-  case S_IFCHR:
-  case S_IFIFO:
-  case S_IFSOCK:
-    return MDBX_RESULT_TRUE;
-  case S_IFDIR:
-  case S_IFLNK:
-  default:
-    return MDBX_INCOMPATIBLE;
-  }
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length) {
-#if defined(_WIN32) || defined(_WIN64)
-  if (mdbx_SetFileInformationByHandle) {
-    FILE_END_OF_FILE_INFO EndOfFileInfo;
-    EndOfFileInfo.EndOfFile.QuadPart = length;
-    return mdbx_SetFileInformationByHandle(fd, FileEndOfFileInfo,
-                                           &EndOfFileInfo,
-                                           sizeof(FILE_END_OF_FILE_INFO))
-               ? MDBX_SUCCESS
-               : GetLastError();
-  } else {
-    LARGE_INTEGER li;
-    li.QuadPart = length;
-    return (SetFilePointerEx(fd, li, NULL, FILE_BEGIN) && SetEndOfFile(fd))
-               ? MDBX_SUCCESS
-               : GetLastError();
-  }
-#else
-  STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
-                    "libmdbx requires 64-bit file I/O on 64-bit systems");
-  return ftruncate(fd, length) == 0 ? MDBX_SUCCESS : errno;
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos) {
-#if defined(_WIN32) || defined(_WIN64)
-  LARGE_INTEGER li;
-  li.QuadPart = pos;
-  return SetFilePointerEx(fd, li, NULL, FILE_BEGIN) ? MDBX_SUCCESS
-                                                    : GetLastError();
-#else
-  STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
-                    "libmdbx requires 64-bit file I/O on 64-bit systems");
-  return (lseek(fd, pos, SEEK_SET) < 0) ? errno : MDBX_SUCCESS;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg) {
-#if defined(_WIN32) || defined(_WIN64)
-  *thread = CreateThread(NULL, 0, start_routine, arg, 0, NULL);
-  return *thread ? MDBX_SUCCESS : GetLastError();
-#else
-  return pthread_create(thread, NULL, start_routine, arg);
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD code = WaitForSingleObject(thread, INFINITE);
-  return waitstatus2errcode(code);
-#else
-  void *unused_retval = &unused_retval;
-  return pthread_join(thread, &unused_retval);
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits) {
-  uint8_t *ptr = (uint8_t *)map->address + offset;
-#if defined(_WIN32) || defined(_WIN64)
-  if (!FlushViewOfFile(ptr, length))
-    return GetLastError();
-#else
-#if defined(__linux__) || defined(__gnu_linux__)
-  if (mode_bits == MDBX_SYNC_NONE && mdbx_linux_kernel_version > 0x02061300)
-    /* Since Linux 2.6.19, MS_ASYNC is in fact a no-op. The kernel properly
-     * tracks dirty pages and flushes them to storage as necessary. */
-    return MDBX_SUCCESS;
-#endif /* Linux */
-  if (msync(ptr, length, (mode_bits & MDBX_SYNC_DATA) ? MS_SYNC : MS_ASYNC))
-    return errno;
-  mode_bits &= ~MDBX_SYNC_DATA;
-#endif
-  return mdbx_fsync(map->fd, mode_bits);
-}
-
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err) {
-#if defined(_WIN32) || defined(_WIN64)
-  (void)pathname;
-  (void)err;
-  if (!mdbx_GetVolumeInformationByHandleW)
-    return MDBX_ENOSYS;
-  DWORD unused, flags;
-  if (!mdbx_GetVolumeInformationByHandleW(handle, nullptr, 0, nullptr, &unused,
-                                          &flags, nullptr, 0))
-    return GetLastError();
-  if ((flags & FILE_READ_ONLY_VOLUME) == 0)
-    return MDBX_EACCESS;
-#else
-  struct statvfs info;
-  if (err != MDBX_ENOFILE) {
-    if (statvfs(pathname, &info))
-      return errno;
-    if ((info.f_flag & ST_RDONLY) == 0)
-      return err;
-  }
-  if (fstatvfs(handle, &info))
-    return errno;
-  if ((info.f_flag & ST_RDONLY) == 0)
-    return (err == MDBX_ENOFILE) ? MDBX_EACCESS : err;
-#endif /* !Windows */
-  return MDBX_SUCCESS;
-}
-
-static int mdbx_check_fs_local(mdbx_filehandle_t handle, int flags) {
-#if defined(_WIN32) || defined(_WIN64)
-  if (mdbx_RunningUnderWine() && !(flags & MDBX_EXCLUSIVE))
-    return ERROR_NOT_CAPABLE /* workaround for Wine */;
-
-  if (GetFileType(handle) != FILE_TYPE_DISK)
-    return ERROR_FILE_OFFLINE;
-
-  if (mdbx_GetFileInformationByHandleEx) {
-    FILE_REMOTE_PROTOCOL_INFO RemoteProtocolInfo;
-    if (mdbx_GetFileInformationByHandleEx(handle, FileRemoteProtocolInfo,
-                                          &RemoteProtocolInfo,
-                                          sizeof(RemoteProtocolInfo))) {
-      if ((RemoteProtocolInfo.Flags & REMOTE_PROTOCOL_INFO_FLAG_OFFLINE) &&
-          !(flags & MDBX_RDONLY))
-        return ERROR_FILE_OFFLINE;
-      if (!(RemoteProtocolInfo.Flags & REMOTE_PROTOCOL_INFO_FLAG_LOOPBACK) &&
-          !(flags & MDBX_EXCLUSIVE))
-        return ERROR_REMOTE_STORAGE_MEDIA_ERROR;
-    }
-  }
-
-  if (mdbx_NtFsControlFile) {
-    NTSTATUS rc;
-    struct {
-      WOF_EXTERNAL_INFO wof_info;
-      union {
-        WIM_PROVIDER_EXTERNAL_INFO wim_info;
-        FILE_PROVIDER_EXTERNAL_INFO_V1 file_info;
-      };
-      size_t reserved_for_microsoft_madness[42];
-    } GetExternalBacking_OutputBuffer;
-    IO_STATUS_BLOCK StatusBlock;
-    rc = mdbx_NtFsControlFile(handle, NULL, NULL, NULL, &StatusBlock,
-                              FSCTL_GET_EXTERNAL_BACKING, NULL, 0,
-                              &GetExternalBacking_OutputBuffer,
-                              sizeof(GetExternalBacking_OutputBuffer));
-    if (NT_SUCCESS(rc)) {
-      if (!(flags & MDBX_EXCLUSIVE))
-        return ERROR_REMOTE_STORAGE_MEDIA_ERROR;
-    } else if (rc != STATUS_OBJECT_NOT_EXTERNALLY_BACKED &&
-               rc != STATUS_INVALID_DEVICE_REQUEST &&
-               rc != STATUS_NOT_SUPPORTED)
-      return ntstatus2errcode(rc);
-  }
-
-  if (mdbx_GetVolumeInformationByHandleW && mdbx_GetFinalPathNameByHandleW) {
-    WCHAR *PathBuffer = mdbx_malloc(sizeof(WCHAR) * INT16_MAX);
-    if (!PathBuffer)
-      return MDBX_ENOMEM;
-
-    int rc = MDBX_SUCCESS;
-    DWORD VolumeSerialNumber, FileSystemFlags;
-    if (!mdbx_GetVolumeInformationByHandleW(handle, PathBuffer, INT16_MAX,
-                                            &VolumeSerialNumber, NULL,
-                                            &FileSystemFlags, NULL, 0)) {
-      rc = GetLastError();
-      goto bailout;
-    }
-
-    if ((flags & MDBX_RDONLY) == 0) {
-      if (FileSystemFlags &
-          (FILE_SEQUENTIAL_WRITE_ONCE | FILE_READ_ONLY_VOLUME |
-           FILE_VOLUME_IS_COMPRESSED)) {
-        rc = ERROR_REMOTE_STORAGE_MEDIA_ERROR;
-        goto bailout;
-      }
-    }
-
-    if (!mdbx_GetFinalPathNameByHandleW(handle, PathBuffer, INT16_MAX,
-                                        FILE_NAME_NORMALIZED |
-                                            VOLUME_NAME_NT)) {
-      rc = GetLastError();
-      goto bailout;
-    }
-
-    if (_wcsnicmp(PathBuffer, L"\\Device\\Mup\\", 12) == 0) {
-      if (!(flags & MDBX_EXCLUSIVE)) {
-        rc = ERROR_REMOTE_STORAGE_MEDIA_ERROR;
-        goto bailout;
-      }
-    } else if (mdbx_GetFinalPathNameByHandleW(handle, PathBuffer, INT16_MAX,
-                                              FILE_NAME_NORMALIZED |
-                                                  VOLUME_NAME_DOS)) {
-      UINT DriveType = GetDriveTypeW(PathBuffer);
-      if (DriveType == DRIVE_NO_ROOT_DIR &&
-          _wcsnicmp(PathBuffer, L"\\\\?\\", 4) == 0 &&
-          _wcsnicmp(PathBuffer + 5, L":\\", 2) == 0) {
-        PathBuffer[7] = 0;
-        DriveType = GetDriveTypeW(PathBuffer + 4);
-      }
-      switch (DriveType) {
-      case DRIVE_CDROM:
-        if (flags & MDBX_RDONLY)
-          break;
-      // fall through
-      case DRIVE_UNKNOWN:
-      case DRIVE_NO_ROOT_DIR:
-      case DRIVE_REMOTE:
-      default:
-        if (!(flags & MDBX_EXCLUSIVE))
-          rc = ERROR_REMOTE_STORAGE_MEDIA_ERROR;
-      // fall through
-      case DRIVE_REMOVABLE:
-      case DRIVE_FIXED:
-      case DRIVE_RAMDISK:
-        break;
-      }
-    }
-  bailout:
-    mdbx_free(PathBuffer);
-    return rc;
-  }
-
-#else
-
-  struct statvfs statvfs_info;
-  if (fstatvfs(handle, &statvfs_info))
-    return errno;
-#if defined(ST_LOCAL) || defined(ST_EXPORTED)
-  const unsigned long st_flags = statvfs_info.f_flag;
-#endif /* ST_LOCAL || ST_EXPORTED */
-
-#if defined(__NetBSD__)
-  const unsigned type = 0;
-  const char *const name = statvfs_info.f_fstypename;
-  const size_t name_len = VFS_NAMELEN;
-#elif defined(_AIX) || defined(__OS400__)
-  const char *const name = statvfs_info.f_basetype;
-  const size_t name_len = sizeof(statvfs_info.f_basetype);
-  struct stat st;
-  if (fstat(handle, &st))
-    return errno;
-  const unsigned type = st.st_vfstype;
-  if ((st.st_flag & FS_REMOTE) != 0 && !(flags & MDBX_EXCLUSIVE))
-    return MDBX_EREMOTE;
-#elif defined(FSTYPSZ) || defined(_FSTYPSZ)
-  const unsigned type = 0;
-  const char *const name = statvfs_info.f_basetype;
-  const size_t name_len = sizeof(statvfs_info.f_basetype);
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-    defined(ST_FSTYPSZ) || defined(_ST_FSTYPSZ)
-  const unsigned type = 0;
-  struct stat st;
-  if (fstat(handle, &st))
-    return errno;
-  const char *const name = st.st_fstype;
-  const size_t name_len = strlen(name);
-#else
-  struct statfs statfs_info;
-  if (fstatfs(handle, &statfs_info))
-    return errno;
-#if defined(__OpenBSD__)
-  const unsigned type = 0;
-#else
-  const unsigned type = statfs_info.f_type;
-#endif
-#if defined(MNT_LOCAL) || defined(MNT_EXPORTED)
-  const unsigned long mnt_flags = statfs_info.f_flags;
-#endif /* MNT_LOCAL || MNT_EXPORTED */
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__) || defined(MFSNAMELEN) ||          \
-    defined(MFSTYPENAMELEN) || defined(VFS_NAMELEN)
-  const char *const name = statfs_info.f_fstypename;
-  const size_t name_len = sizeof(statfs_info.f_fstypename);
-#elif defined(__ANDROID_API__) && __ANDROID_API__ < 21
-  const char *const name = "";
-  const unsigned name_len = 0;
-#else
-
-  const char *name = "";
-  unsigned name_len = 0;
-
-  struct stat st;
-  if (fstat(handle, &st))
-    return errno;
-
-  char pathbuf[PATH_MAX];
-  FILE *mounted = nullptr;
-#if defined(__linux__) || defined(__gnu_linux__)
-  mounted = setmntent("/proc/mounts", "r");
-#endif /* Linux */
-  if (!mounted)
-    mounted = setmntent("/etc/mtab", "r");
-  if (mounted) {
-    const struct mntent *ent;
-#if defined(_BSD_SOURCE) || defined(_SVID_SOURCE) || defined(__BIONIC__) ||    \
-    (defined(_DEFAULT_SOURCE) && __GLIBC_PREREQ(2, 19))
-    struct mntent entbuf;
-    const bool should_copy = false;
-    while (nullptr !=
-           (ent = getmntent_r(mounted, &entbuf, pathbuf, sizeof(pathbuf))))
-#else
-    const bool should_copy = true;
-    while (nullptr != (ent = getmntent(mounted)))
-#endif
-    {
-      struct stat mnt;
-      if (!stat(ent->mnt_dir, &mnt) && mnt.st_dev == st.st_dev) {
-        if (should_copy) {
-          name =
-              strncpy(pathbuf, ent->mnt_fsname, name_len = sizeof(pathbuf) - 1);
-          pathbuf[name_len] = 0;
-        } else {
-          name = ent->mnt_fsname;
-          name_len = strlen(name);
-        }
-        break;
-      }
-    }
-    endmntent(mounted);
-  }
-#endif /* !xBSD && !Android/Bionic */
-#endif
-
-  if (name_len) {
-    if (((name_len > 2 && strncasecmp("nfs", name, 3) == 0) ||
-         strncasecmp("cifs", name, name_len) == 0 ||
-         strncasecmp("ncpfs", name, name_len) == 0 ||
-         strncasecmp("smbfs", name, name_len) == 0 ||
-         ((name_len > 3 && strncasecmp("fuse", name, 4) == 0) &&
-          strncasecmp("fuseblk", name, name_len) != 0)) &&
-        !(flags & MDBX_EXCLUSIVE))
-      return MDBX_EREMOTE;
-    if (strcasecmp("ftp", name) == 0 || strcasecmp("http", name) == 0 ||
-        strcasecmp("sshfs", name) == 0)
-      return MDBX_EREMOTE;
-  }
-
-#ifdef ST_LOCAL
-  if ((st_flags & ST_LOCAL) == 0 && !(flags & MDBX_EXCLUSIVE))
-    return MDBX_EREMOTE;
-#elif defined(MNT_LOCAL)
-  if ((mnt_flags & MNT_LOCAL) == 0 && !(flags & MDBX_EXCLUSIVE))
-    return MDBX_EREMOTE;
-#endif /* ST/MNT_LOCAL */
-
-#ifdef ST_EXPORTED
-  if ((st_flags & ST_EXPORTED) != 0 && !(flags & MDBX_RDONLY))
-    return MDBX_EREMOTE;
-#elif defined(MNT_EXPORTED)
-  if ((mnt_flags & MNT_EXPORTED) != 0 && !(flags & MDBX_RDONLY))
-    return MDBX_EREMOTE;
-#endif /* ST/MNT_EXPORTED */
-
-  switch (type) {
-  case 0xFF534D42 /* CIFS_MAGIC_NUMBER */:
-  case 0x6969 /* NFS_SUPER_MAGIC */:
-  case 0x564c /* NCP_SUPER_MAGIC */:
-  case 0x517B /* SMB_SUPER_MAGIC */:
-#if defined(__digital__) || defined(__osf__) || defined(__osf)
-  case 0x0E /* Tru64 NFS */:
-#endif
-#ifdef ST_FST_NFS
-  case ST_FST_NFS:
-#endif
-    if ((flags & MDBX_EXCLUSIVE) == 0)
-      return MDBX_EREMOTE;
-  case 0:
-  default:
-    break;
-  }
-#endif /* Unix */
-
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t size, const size_t limit,
-                                 const unsigned options) {
-  assert(size <= limit);
-  map->limit = 0;
-  map->current = 0;
-  map->address = nullptr;
-#if defined(_WIN32) || defined(_WIN64)
-  map->section = NULL;
-  map->filesize = 0;
-#endif /* Windows */
-
-  int err = mdbx_check_fs_local(map->fd, flags);
-  if (unlikely(err != MDBX_SUCCESS))
-    return err;
-
-  if ((flags & MDBX_RDONLY) == 0 && (options & MMAP_OPTION_TRUNCATE) != 0) {
-    err = mdbx_ftruncate(map->fd, size);
-    if (err != MDBX_SUCCESS)
-      return err;
-#if defined(_WIN32) || defined(_WIN64)
-    map->filesize = size;
-#else
-    map->current = size;
-#endif
-  } else {
-    uint64_t filesize = 0;
-    err = mdbx_filesize(map->fd, &filesize);
-    if (err != MDBX_SUCCESS)
-      return err;
-#if defined(_WIN32) || defined(_WIN64)
-    map->filesize = filesize;
-#else
-    map->current = (filesize > limit) ? limit : (size_t)filesize;
-#endif
-  }
-
-#if defined(_WIN32) || defined(_WIN64)
-  LARGE_INTEGER SectionSize;
-  SectionSize.QuadPart = size;
-  err = NtCreateSection(
-      &map->section,
-      /* DesiredAccess */
-      (flags & MDBX_WRITEMAP)
-          ? SECTION_QUERY | SECTION_MAP_READ | SECTION_EXTEND_SIZE |
-                SECTION_MAP_WRITE
-          : SECTION_QUERY | SECTION_MAP_READ | SECTION_EXTEND_SIZE,
-      /* ObjectAttributes */ NULL, /* MaximumSize (InitialSize) */ &SectionSize,
-      /* SectionPageProtection */
-      (flags & MDBX_RDONLY) ? PAGE_READONLY : PAGE_READWRITE,
-      /* AllocationAttributes */ SEC_RESERVE, map->fd);
-  if (!NT_SUCCESS(err))
-    return ntstatus2errcode(err);
-
-  SIZE_T ViewSize =
-      (flags & MDBX_RDONLY) ? 0 : mdbx_RunningUnderWine() ? size : limit;
-  err = NtMapViewOfSection(
-      map->section, GetCurrentProcess(), &map->address,
-      /* ZeroBits */ 0,
-      /* CommitSize */ 0,
-      /* SectionOffset */ NULL, &ViewSize,
-      /* InheritDisposition */ ViewUnmap,
-      /* AllocationType */ (flags & MDBX_RDONLY) ? 0 : MEM_RESERVE,
-      /* Win32Protect */
-      (flags & MDBX_WRITEMAP) ? PAGE_READWRITE : PAGE_READONLY);
-  if (!NT_SUCCESS(err)) {
-    NtClose(map->section);
-    map->section = 0;
-    map->address = nullptr;
-    return ntstatus2errcode(err);
-  }
-  assert(map->address != MAP_FAILED);
-
-  map->current = (size_t)SectionSize.QuadPart;
-  map->limit = ViewSize;
-
-#else
-
-#ifndef MAP_TRYFIXED
-#define MAP_TRYFIXED 0
-#endif
-
-#ifndef MAP_HASSEMAPHORE
-#define MAP_HASSEMAPHORE 0
-#endif
-
-#ifndef MAP_CONCEAL
-#define MAP_CONCEAL 0
-#endif
-
-#ifndef MAP_NOSYNC
-#define MAP_NOSYNC 0
-#endif
-
-  map->address = mmap(
-      NULL, limit, (flags & MDBX_WRITEMAP) ? PROT_READ | PROT_WRITE : PROT_READ,
-      MAP_SHARED | MAP_FILE |
-          (F_ISSET(flags, MDBX_UTTERLY_NOSYNC) ? MAP_NOSYNC : 0) |
-          ((options & MMAP_OPTION_SEMAPHORE) ? MAP_HASSEMAPHORE | MAP_NOSYNC
-                                             : MAP_CONCEAL),
-      map->fd, 0);
-
-  if (unlikely(map->address == MAP_FAILED)) {
-    map->limit = 0;
-    map->current = 0;
-    map->address = nullptr;
-    return errno;
-  }
-  map->limit = limit;
-
-#ifdef MADV_DONTFORK
-  if (unlikely(madvise(map->address, map->limit, MADV_DONTFORK) != 0))
-    return errno;
-#endif
-#ifdef MADV_NOHUGEPAGE
-  (void)madvise(map->address, map->limit, MADV_NOHUGEPAGE);
-#endif
-
-#endif
-
-  VALGRIND_MAKE_MEM_DEFINED(map->address, map->current);
-  ASAN_UNPOISON_MEMORY_REGION(map->address, map->current);
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map) {
-  VALGRIND_MAKE_MEM_NOACCESS(map->address, map->current);
-  /* Unpoisoning is required for ASAN to avoid false-positive diagnostic
-   * when this memory will re-used by malloc or another mmapping.
-   * See https://github.com/erthink/libmdbx/pull/93#issuecomment-613687203 */
-  ASAN_UNPOISON_MEMORY_REGION(map->address, map->limit);
-#if defined(_WIN32) || defined(_WIN64)
-  if (map->section)
-    NtClose(map->section);
-  NTSTATUS rc = NtUnmapViewOfSection(GetCurrentProcess(), map->address);
-  if (!NT_SUCCESS(rc))
-    ntstatus2errcode(rc);
-#else
-  if (unlikely(munmap(map->address, map->limit)))
-    return errno;
-#endif
-
-  map->limit = 0;
-  map->current = 0;
-  map->address = nullptr;
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t size,
-                                    size_t limit, const bool may_move) {
-  assert(size <= limit);
-#if defined(_WIN32) || defined(_WIN64)
-  assert(size != map->current || limit != map->limit || size < map->filesize);
-
-  NTSTATUS status;
-  LARGE_INTEGER SectionSize;
-  int err, rc = MDBX_SUCCESS;
-
-  if (!(flags & MDBX_RDONLY) && limit == map->limit && size > map->current &&
-      /* workaround for Wine */ mdbx_NtExtendSection) {
-    /* growth rw-section */
-    SectionSize.QuadPart = size;
-    status = mdbx_NtExtendSection(map->section, &SectionSize);
-    if (!NT_SUCCESS(status))
-      return ntstatus2errcode(status);
-    map->current = size;
-    if (map->filesize < size)
-      map->filesize = size;
-    return MDBX_SUCCESS;
-  }
-
-  if (limit > map->limit) {
-    /* check ability of address space for growth before unmap */
-    PVOID BaseAddress = (PBYTE)map->address + map->limit;
-    SIZE_T RegionSize = limit - map->limit;
-    status = NtAllocateVirtualMemory(GetCurrentProcess(), &BaseAddress, 0,
-                                     &RegionSize, MEM_RESERVE, PAGE_NOACCESS);
-    if (status == /* STATUS_CONFLICTING_ADDRESSES */ 0xC0000018)
-      return MDBX_UNABLE_EXTEND_MAPSIZE;
-    if (!NT_SUCCESS(status))
-      return ntstatus2errcode(status);
-
-    status = NtFreeVirtualMemory(GetCurrentProcess(), &BaseAddress, &RegionSize,
-                                 MEM_RELEASE);
-    if (!NT_SUCCESS(status))
-      return ntstatus2errcode(status);
-  }
-
-  /* Windows unable:
-   *  - shrink a mapped file;
-   *  - change size of mapped view;
-   *  - extend read-only mapping;
-   * Therefore we should unmap/map entire section. */
-  status = NtUnmapViewOfSection(GetCurrentProcess(), map->address);
-  if (!NT_SUCCESS(status))
-    return ntstatus2errcode(status);
-  status = NtClose(map->section);
-  map->section = NULL;
-  PVOID ReservedAddress = NULL;
-  SIZE_T ReservedSize = limit;
-
-  if (!NT_SUCCESS(status)) {
-  bailout_ntstatus:
-    err = ntstatus2errcode(status);
-  bailout:
-    map->address = NULL;
-    map->current = map->limit = 0;
-    if (ReservedAddress) {
-      ReservedSize = 0;
-      status = NtFreeVirtualMemory(GetCurrentProcess(), &ReservedAddress,
-                                   &ReservedSize, MEM_RELEASE);
-      assert(NT_SUCCESS(status));
-      (void)status;
-    }
-    return err;
-  }
-
-retry_file_and_section:
-  /* resizing of the file may take a while,
-   * therefore we reserve address space to avoid occupy it by other threads */
-  ReservedAddress = map->address;
-  status = NtAllocateVirtualMemory(GetCurrentProcess(), &ReservedAddress, 0,
-                                   &ReservedSize, MEM_RESERVE, PAGE_NOACCESS);
-  if (!NT_SUCCESS(status)) {
-    ReservedAddress = NULL;
-    if (status != /* STATUS_CONFLICTING_ADDRESSES */ 0xC0000018)
-      goto bailout_ntstatus /* no way to recovery */;
-
-    if (may_move)
-      /* the base address could be changed */
-      map->address = NULL;
-  }
-
-  err = mdbx_filesize(map->fd, &map->filesize);
-  if (err != MDBX_SUCCESS)
-    goto bailout;
-
-  if ((flags & MDBX_RDONLY) == 0 && map->filesize != size) {
-    err = mdbx_ftruncate(map->fd, size);
-    if (err == MDBX_SUCCESS)
-      map->filesize = size;
-    /* ignore error, because Windows unable shrink file
-     * that already mapped (by another process) */
-  }
-
-  SectionSize.QuadPart = size;
-  status = NtCreateSection(
-      &map->section,
-      /* DesiredAccess */
-      (flags & MDBX_WRITEMAP)
-          ? SECTION_QUERY | SECTION_MAP_READ | SECTION_EXTEND_SIZE |
-                SECTION_MAP_WRITE
-          : SECTION_QUERY | SECTION_MAP_READ | SECTION_EXTEND_SIZE,
-      /* ObjectAttributes */ NULL,
-      /* MaximumSize (InitialSize) */ &SectionSize,
-      /* SectionPageProtection */
-      (flags & MDBX_RDONLY) ? PAGE_READONLY : PAGE_READWRITE,
-      /* AllocationAttributes */ SEC_RESERVE, map->fd);
-
-  if (!NT_SUCCESS(status))
-    goto bailout_ntstatus;
-
-  if (ReservedAddress) {
-    /* release reserved address space */
-    ReservedSize = 0;
-    status = NtFreeVirtualMemory(GetCurrentProcess(), &ReservedAddress,
-                                 &ReservedSize, MEM_RELEASE);
-    ReservedAddress = NULL;
-    if (!NT_SUCCESS(status))
-      goto bailout_ntstatus;
-  }
-
-retry_mapview:;
-  SIZE_T ViewSize = (flags & MDBX_RDONLY) ? size : limit;
-  status = NtMapViewOfSection(
-      map->section, GetCurrentProcess(), &map->address,
-      /* ZeroBits */ 0,
-      /* CommitSize */ 0,
-      /* SectionOffset */ NULL, &ViewSize,
-      /* InheritDisposition */ ViewUnmap,
-      /* AllocationType */ (flags & MDBX_RDONLY) ? 0 : MEM_RESERVE,
-      /* Win32Protect */
-      (flags & MDBX_WRITEMAP) ? PAGE_READWRITE : PAGE_READONLY);
-
-  if (!NT_SUCCESS(status)) {
-    if (status == /* STATUS_CONFLICTING_ADDRESSES */ 0xC0000018 &&
-        map->address && may_move) {
-      /* try remap at another base address */
-      map->address = NULL;
-      goto retry_mapview;
-    }
-    NtClose(map->section);
-    map->section = NULL;
-
-    if (map->address && (size != map->current || limit != map->limit)) {
-      /* try remap with previously size and limit,
-       * but will return MDBX_UNABLE_EXTEND_MAPSIZE on success */
-      rc = MDBX_UNABLE_EXTEND_MAPSIZE;
-      size = map->current;
-      ReservedSize = limit = map->limit;
-      goto retry_file_and_section;
-    }
-
-    /* no way to recovery */
-    goto bailout_ntstatus;
-  }
-  assert(map->address != MAP_FAILED);
-
-  map->current = (size_t)SectionSize.QuadPart;
-  map->limit = ViewSize;
-
-#else
-
-  uint64_t filesize = 0;
-  int rc = mdbx_filesize(map->fd, &filesize);
-  if (rc != MDBX_SUCCESS)
-    return rc;
-
-  if (flags & MDBX_RDONLY) {
-    map->current = (filesize > limit) ? limit : (size_t)filesize;
-    if (map->current != size)
-      rc = MDBX_UNABLE_EXTEND_MAPSIZE;
-  } else if (filesize != size) {
-    rc = mdbx_ftruncate(map->fd, size);
-    if (rc != MDBX_SUCCESS)
-      return rc;
-    map->current = size;
-  }
-
-  if (limit == map->limit)
-    return MDBX_SUCCESS;
-
-  if (limit < map->limit) {
-    /* unmap an excess at end of mapping. */
-    if (unlikely(munmap(map->dxb + limit, map->limit - limit)))
-      return errno;
-    map->limit = limit;
-    return MDBX_SUCCESS;
-  }
-
-  assert(limit > map->limit);
-  uint8_t *ptr = MAP_FAILED;
-
-#if defined(MREMAP_MAYMOVE)
-  ptr = mremap(map->address, map->limit, limit, may_move ? MREMAP_MAYMOVE : 0);
-  if (ptr == MAP_FAILED) {
-    const int err = errno;
-    switch (err) {
-    default:
-      return err;
-    case EAGAIN:
-    case ENOMEM:
-      return MDBX_UNABLE_EXTEND_MAPSIZE;
-    case EFAULT /* MADV_DODUMP / MADV_DONTDUMP are mixed for mmap-range */:
-      break;
-    }
-  }
-#endif /* MREMAP_MAYMOVE */
-
-  const unsigned mmap_flags =
-      MAP_CONCEAL | MAP_SHARED | MAP_FILE |
-      (F_ISSET(flags, MDBX_UTTERLY_NOSYNC) ? MAP_NOSYNC : 0);
-  const unsigned mmap_prot =
-      (flags & MDBX_WRITEMAP) ? PROT_READ | PROT_WRITE : PROT_READ;
-
-  if (ptr == MAP_FAILED) {
-    /* Try to mmap additional space beyond the end of mapping. */
-    ptr = mmap(map->dxb + map->limit, limit - map->limit, mmap_prot,
-               mmap_flags
-#if defined(MAP_FIXED_NOREPLACE)
-                   | MAP_FIXED_NOREPLACE
-#endif /* MAP_FIXED_NOREPLACE */
-               ,
-               map->fd, map->limit);
-    if (ptr == map->dxb + map->limit)
-      ptr = map->dxb;
-    else if (ptr != MAP_FAILED) {
-      /* the desired address is busy, unmap unsuitable one */
-      if (unlikely(munmap(ptr, limit - map->limit)))
-        return errno;
-      ptr = MAP_FAILED;
-    } else {
-      const int err = errno;
-      switch (err) {
-      default:
-        return err;
-      case EAGAIN:
-      case ENOMEM:
-        return MDBX_UNABLE_EXTEND_MAPSIZE;
-      case EEXIST: /* address busy */
-      case EINVAL: /* kernel don't support MAP_FIXED_NOREPLACE */
-        break;
-      }
-    }
-  }
-
-  if (ptr == MAP_FAILED) {
-    /* unmap and map again whole region */
-    if (!may_move) {
-      /* TODO: Perhaps here it is worth to implement suspend/resume threads
-       * and perform unmap/map as like for Windows. */
-      return MDBX_UNABLE_EXTEND_MAPSIZE;
-    }
-
-    if (unlikely(munmap(map->address, map->limit)))
-      return errno;
-
-    ptr = mmap(map->address, limit, mmap_prot, mmap_flags, map->fd, 0);
-    if (unlikely(ptr == MAP_FAILED)) {
-      ptr = mmap(map->address, map->limit, mmap_prot, mmap_flags, map->fd, 0);
-      if (unlikely(ptr == MAP_FAILED)) {
-        VALGRIND_MAKE_MEM_NOACCESS(map->address, map->current);
-        /* Unpoisoning is required for ASAN to avoid false-positive diagnostic
-         * when this memory will re-used by malloc or another mmapping.
-         * See https://github.com/erthink/libmdbx/pull/93#issuecomment-613687203
-         */
-        ASAN_UNPOISON_MEMORY_REGION(map->address, map->limit);
-        map->limit = 0;
-        map->current = 0;
-        map->address = nullptr;
-        return errno;
-      }
-      rc = MDBX_UNABLE_EXTEND_MAPSIZE;
-      limit = map->limit;
-    }
-  }
-
-  assert(ptr && ptr != MAP_FAILED);
-  if (map->address != ptr) {
-    VALGRIND_MAKE_MEM_NOACCESS(map->address, map->current);
-    /* Unpoisoning is required for ASAN to avoid false-positive diagnostic
-     * when this memory will re-used by malloc or another mmapping.
-     * See https://github.com/erthink/libmdbx/pull/93#issuecomment-613687203
-     */
-    ASAN_UNPOISON_MEMORY_REGION(map->address, map->limit);
-
-    VALGRIND_MAKE_MEM_DEFINED(ptr, map->current);
-    ASAN_UNPOISON_MEMORY_REGION(ptr, map->current);
-    map->address = ptr;
-  }
-  map->limit = limit;
-
-#ifdef MADV_DONTFORK
-  if (unlikely(madvise(map->address, map->limit, MADV_DONTFORK) != 0))
-    return errno;
-#endif /* MADV_DONTFORK */
-
-#ifdef MADV_NOHUGEPAGE
-  (void)madvise(map->address, map->limit, MADV_NOHUGEPAGE);
-#endif /* MADV_NOHUGEPAGE */
-
-#endif /* POSIX / Windows */
-
-  return rc;
-}
-
-/*----------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC __cold void mdbx_osal_jitter(bool tiny) {
-  for (;;) {
-#if defined(_M_IX86) || defined(_M_X64) || defined(__i386__) ||                \
-    defined(__x86_64__)
-    const unsigned salt = 277u * (unsigned)__rdtsc();
-#else
-    const unsigned salt = rand();
-#endif
-
-    const unsigned coin = salt % (tiny ? 29u : 43u);
-    if (coin < 43 / 3)
-      break;
-#if defined(_WIN32) || defined(_WIN64)
-    SwitchToThread();
-    if (coin > 43 * 2 / 3)
-      Sleep(1);
-#else
-    sched_yield();
-    if (coin > 43 * 2 / 3)
-      usleep(coin);
-#endif
-  }
-}
-
-#if defined(_WIN32) || defined(_WIN64)
-#elif defined(__APPLE__) || defined(__MACH__)
-#include <mach/mach_time.h>
-#elif defined(__linux__) || defined(__gnu_linux__)
-static __cold clockid_t choice_monoclock(void) {
-  struct timespec probe;
-#if defined(CLOCK_BOOTTIME)
-  if (clock_gettime(CLOCK_BOOTTIME, &probe) == 0)
-    return CLOCK_BOOTTIME;
-#elif defined(CLOCK_MONOTONIC_RAW)
-  if (clock_gettime(CLOCK_MONOTONIC_RAW, &probe) == 0)
-    return CLOCK_MONOTONIC_RAW;
-#elif defined(CLOCK_MONOTONIC_COARSE)
-  if (clock_gettime(CLOCK_MONOTONIC_COARSE, &probe) == 0)
-    return CLOCK_MONOTONIC_COARSE;
-#endif
-  return CLOCK_MONOTONIC;
-}
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_WIN32) || defined(_WIN64)
-static LARGE_INTEGER performance_frequency;
-#elif defined(__APPLE__) || defined(__MACH__)
-static uint64_t ratio_16dot16_to_monotine;
-#endif
-
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16) {
-#if defined(_WIN32) || defined(_WIN64)
-  if (unlikely(performance_frequency.QuadPart == 0))
-    QueryPerformanceFrequency(&performance_frequency);
-  const uint64_t ratio = performance_frequency.QuadPart;
-#elif defined(__APPLE__) || defined(__MACH__)
-  if (unlikely(ratio_16dot16_to_monotine == 0)) {
-    mach_timebase_info_data_t ti;
-    mach_timebase_info(&ti);
-    ratio_16dot16_to_monotine = UINT64_C(1000000000) * ti.denom / ti.numer;
-  }
-  const uint64_t ratio = ratio_16dot16_to_monotine;
-#else
-  const uint64_t ratio = UINT64_C(1000000000);
-#endif
-  return (ratio * seconds_16dot16 + 32768) >> 16;
-}
-
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime) {
-  static uint64_t limit;
-  if (unlikely(monotime > limit)) {
-    if (limit != 0)
-      return UINT32_MAX;
-    limit = mdbx_osal_16dot16_to_monotime(UINT32_MAX - 1);
-    if (monotime > limit)
-      return UINT32_MAX;
-  }
-#if defined(_WIN32) || defined(_WIN64)
-  return (uint32_t)((monotime << 16) / performance_frequency.QuadPart);
-#elif defined(__APPLE__) || defined(__MACH__)
-  return (uint32_t)((monotime << 16) / ratio_16dot16_to_monotine);
-#else
-  return (uint32_t)(monotime * 128 / 1953125);
-#endif
-}
-
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  LARGE_INTEGER counter;
-  counter.QuadPart = 0;
-  QueryPerformanceCounter(&counter);
-  return counter.QuadPart;
-#elif defined(__APPLE__) || defined(__MACH__)
-  return mach_absolute_time();
-#else
-
-#if defined(__linux__) || defined(__gnu_linux__)
-  static clockid_t posix_clockid = -1;
-  if (unlikely(posix_clockid < 0))
-    posix_clockid = choice_monoclock();
-#elif defined(CLOCK_MONOTONIC)
-#define posix_clockid CLOCK_MONOTONIC
-#else
-#define posix_clockid CLOCK_REALTIME
-#endif
-
-  struct timespec ts;
-  if (unlikely(clock_gettime(posix_clockid, &ts) != 0)) {
-    ts.tv_nsec = 0;
-    ts.tv_sec = 0;
-  }
-  return ts.tv_sec * UINT64_C(1000000000) + ts.tv_nsec;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-
-static void bootid_shake(bin128_t *p) {
-  /* Bob Jenkins's PRNG: https://burtleburtle.net/bob/rand/smallprng.html */
-  const uint32_t e = p->a - (p->b << 23 | p->b >> 9);
-  p->a = p->b ^ (p->c << 16 | p->c >> 16);
-  p->b = p->c + (p->d << 11 | p->d >> 21);
-  p->c = p->d + e;
-  p->d = e + p->a;
-}
-
-static void bootid_collect(bin128_t *p, const void *s, size_t n) {
-  p->y += UINT64_C(64526882297375213);
-  bootid_shake(p);
-  for (size_t i = 0; i < n; ++i) {
-    bootid_shake(p);
-    p->y ^= UINT64_C(48797879452804441) * ((const uint8_t *)s)[i];
-    bootid_shake(p);
-    p->y += 14621231;
-  }
-  bootid_shake(p);
-
-  /* minor non-linear tomfoolery */
-  const unsigned z = p->x % 61;
-  p->y = p->y << z | p->y >> (64 - z);
-  bootid_shake(p);
-  bootid_shake(p);
-  const unsigned q = p->x % 59;
-  p->y = p->y << q | p->y >> (64 - q);
-  bootid_shake(p);
-  bootid_shake(p);
-  bootid_shake(p);
-}
-
-#if defined(_WIN32) || defined(_WIN64)
-
-static uint64_t windows_systemtime_ms() {
-  FILETIME ft;
-  GetSystemTimeAsFileTime(&ft);
-  return ((uint64_t)ft.dwHighDateTime << 32 | ft.dwLowDateTime) / 10000ul;
-}
-
-static uint64_t windows_bootime(void) {
-  unsigned confirmed = 0;
-  uint64_t boottime = 0;
-  uint64_t up0 = mdbx_GetTickCount64();
-  uint64_t st0 = windows_systemtime_ms();
-  for (uint64_t fuse = st0; up0 && st0 < fuse + 1000 * 1000u / 42;) {
-    YieldProcessor();
-    const uint64_t up1 = mdbx_GetTickCount64();
-    const uint64_t st1 = windows_systemtime_ms();
-    if (st1 > fuse && st1 == st0 && up1 == up0) {
-      uint64_t diff = st1 - up1;
-      if (boottime == diff) {
-        if (++confirmed > 4)
-          return boottime;
-      } else {
-        confirmed = 0;
-        boottime = diff;
-      }
-      fuse = st1;
-      Sleep(1);
-    }
-    st0 = st1;
-    up0 = up1;
-  }
-  return 0;
-}
-
-static LSTATUS mdbx_RegGetValue(HKEY hKey, LPCSTR lpSubKey, LPCSTR lpValue,
-                                PVOID pvData, LPDWORD pcbData) {
-  LSTATUS rc;
-  if (!mdbx_RegGetValueA) {
-    /* an old Windows 2000/XP */
-    HKEY hSubKey;
-    rc = RegOpenKeyA(hKey, lpSubKey, &hSubKey);
-    if (rc == ERROR_SUCCESS) {
-      rc = RegQueryValueExA(hSubKey, lpValue, NULL, NULL, pvData, pcbData);
-      RegCloseKey(hSubKey);
-    }
-    return rc;
-  }
-
-  rc = mdbx_RegGetValueA(hKey, lpSubKey, lpValue, RRF_RT_ANY, NULL, pvData,
-                         pcbData);
-  if (rc != ERROR_FILE_NOT_FOUND)
-    return rc;
-
-  rc = mdbx_RegGetValueA(hKey, lpSubKey, lpValue,
-                         RRF_RT_ANY | 0x00010000 /* RRF_SUBKEY_WOW6464KEY */,
-                         NULL, pvData, pcbData);
-  if (rc != ERROR_FILE_NOT_FOUND)
-    return rc;
-  return mdbx_RegGetValueA(hKey, lpSubKey, lpValue,
-                           RRF_RT_ANY | 0x00020000 /* RRF_SUBKEY_WOW6432KEY */,
-                           NULL, pvData, pcbData);
-}
-#endif
-
-static __cold __maybe_unused bool bootid_parse_uuid(bin128_t *s, const void *p,
-                                                    const size_t n) {
-  if (n > 31) {
-    unsigned bits = 0;
-    for (unsigned i = 0; i < n; ++i) /* try parse an UUID in text form */ {
-      uint8_t c = ((const uint8_t *)p)[i];
-      if (c >= '0' && c <= '9')
-        c -= '0';
-      else if (c >= 'a' && c <= 'f')
-        c -= 'a' - 10;
-      else if (c >= 'A' && c <= 'F')
-        c -= 'A' - 10;
-      else
-        continue;
-      assert(c <= 15);
-      c ^= s->y >> 60;
-      s->y = s->y << 4 | s->x >> 60;
-      s->x = s->x << 4 | c;
-      bits += 4;
-    }
-    if (bits > 42 * 3)
-      /* UUID parsed successfully */
-      return true;
-  }
-
-  if (n > 15) /* is enough handle it as a binary? */ {
-    if (n == sizeof(bin128_t)) {
-      bin128_t aligned;
-      memcpy(&aligned, p, sizeof(bin128_t));
-      s->x += aligned.x;
-      s->y += aligned.y;
-    } else
-      bootid_collect(s, p, n);
-    return true;
-  }
-
-  if (n)
-    bootid_collect(s, p, n);
-  return false;
-}
-
-__cold MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void) {
-  bin128_t bin = {{0, 0}};
-  bool got_machineid = false, got_boottime = false, got_bootseq = false;
-
-#if defined(__linux__) || defined(__gnu_linux__)
-  {
-    const int fd =
-        open("/proc/sys/kernel/random/boot_id", O_RDONLY | O_NOFOLLOW);
-    if (fd != -1) {
-      struct statfs fs;
-      char buf[42];
-      const ssize_t len =
-          (fstatfs(fd, &fs) == 0 && fs.f_type == /* procfs */ 0x9FA0)
-              ? read(fd, buf, sizeof(buf))
-              : -1;
-      const int err = close(fd);
-      assert(err == 0);
-      (void)err;
-      if (len > 0 && bootid_parse_uuid(&bin, buf, len))
-        return bin;
-    }
-  }
-#endif /* Linux */
-
-#if defined(__APPLE__) || defined(__MACH__)
-  {
-    char buf[42];
-    size_t len = sizeof(buf);
-    if (!sysctlbyname("kern.bootsessionuuid", buf, &len, nullptr, 0) &&
-        bootid_parse_uuid(&bin, buf, len))
-      return bin;
-
-#if defined(__MAC_OS_X_VERSION_MIN_REQUIRED) &&                                \
-    __MAC_OS_X_VERSION_MIN_REQUIRED > 1050
-    uuid_t uuid;
-    struct timespec wait = {0, 1000000000u / 42};
-    if (!gethostuuid(uuid, &wait) &&
-        bootid_parse_uuid(&bin, uuid, sizeof(uuid)))
-      got_machineid = true;
-#endif /* > 10.5 */
-
-    struct timeval boottime;
-    len = sizeof(boottime);
-    if (!sysctlbyname("kern.boottime", &boottime, &len, nullptr, 0) &&
-        len == sizeof(boottime) && boottime.tv_sec)
-      got_boottime = true;
-  }
-#endif /* Apple/Darwin */
-
-#if defined(_WIN32) || defined(_WIN64)
-  {
-    union buf {
-      DWORD BootId;
-      DWORD BaseTime;
-      SYSTEM_TIMEOFDAY_INFORMATION SysTimeOfDayInfo;
-      struct {
-        LARGE_INTEGER BootTime;
-        LARGE_INTEGER CurrentTime;
-        LARGE_INTEGER TimeZoneBias;
-        ULONG TimeZoneId;
-        ULONG Reserved;
-        ULONGLONG BootTimeBias;
-        ULONGLONG SleepTimeBias;
-      } SysTimeOfDayInfoHacked;
-      wchar_t MachineGuid[42];
-      char DigitalProductId[248];
-    } buf;
-
-    static const char HKLM_MicrosoftCryptography[] =
-        "SOFTWARE\\Microsoft\\Cryptography";
-    DWORD len = sizeof(buf);
-    /* Windows is madness and must die */
-    if (mdbx_RegGetValue(HKEY_LOCAL_MACHINE, HKLM_MicrosoftCryptography,
-                         "MachineGuid", &buf.MachineGuid,
-                         &len) == ERROR_SUCCESS &&
-        len > 42 && len < sizeof(buf))
-      got_machineid = bootid_parse_uuid(&bin, &buf.MachineGuid, len);
-
-    if (!got_machineid) {
-      /* again, Windows is madness */
-      static const char HKLM_WindowsNT[] =
-          "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion";
-      static const char HKLM_WindowsNT_DPK[] =
-          "SOFTWARE\\Microsoft\\Windows "
-          "NT\\CurrentVersion\\DefaultProductKey";
-      static const char HKLM_WindowsNT_DPK2[] =
-          "SOFTWARE\\Microsoft\\Windows "
-          "NT\\CurrentVersion\\DefaultProductKey2";
-
-      len = sizeof(buf);
-      if (mdbx_RegGetValue(HKEY_LOCAL_MACHINE, HKLM_WindowsNT,
-                           "DigitalProductId", &buf.DigitalProductId,
-                           &len) == ERROR_SUCCESS &&
-          len > 42 && len < sizeof(buf)) {
-        bootid_collect(&bin, &buf.DigitalProductId, len);
-        got_machineid = true;
-      }
-      len = sizeof(buf);
-      if (mdbx_RegGetValue(HKEY_LOCAL_MACHINE, HKLM_WindowsNT_DPK,
-                           "DigitalProductId", &buf.DigitalProductId,
-                           &len) == ERROR_SUCCESS &&
-          len > 42 && len < sizeof(buf)) {
-        bootid_collect(&bin, &buf.DigitalProductId, len);
-        got_machineid = true;
-      }
-      len = sizeof(buf);
-      if (mdbx_RegGetValue(HKEY_LOCAL_MACHINE, HKLM_WindowsNT_DPK2,
-                           "DigitalProductId", &buf.DigitalProductId,
-                           &len) == ERROR_SUCCESS &&
-          len > 42 && len < sizeof(buf)) {
-        bootid_collect(&bin, &buf.DigitalProductId, len);
-        got_machineid = true;
-      }
-    }
-
-    static const char HKLM_PrefetcherParams[] =
-        "SYSTEM\\CurrentControlSet\\Control\\Session Manager\\Memory "
-        "Management\\PrefetchParameters";
-    len = sizeof(buf);
-    if (mdbx_RegGetValue(HKEY_LOCAL_MACHINE, HKLM_PrefetcherParams, "BootId",
-                         &buf.BootId, &len) == ERROR_SUCCESS &&
-        len > 1 && len < sizeof(buf)) {
-      bootid_collect(&bin, &buf.BootId, len);
-      got_bootseq = true;
-    }
-
-    len = sizeof(buf);
-    if (mdbx_RegGetValue(HKEY_LOCAL_MACHINE, HKLM_PrefetcherParams, "BaseTime",
-                         &buf.BaseTime, &len) == ERROR_SUCCESS &&
-        len >= sizeof(buf.BaseTime) && buf.BaseTime) {
-      bootid_collect(&bin, &buf.BaseTime, len);
-      got_boottime = true;
-    }
-
-    /* BootTime from SYSTEM_TIMEOFDAY_INFORMATION */
-    NTSTATUS status = NtQuerySystemInformation(
-        0x03 /* SystemTmeOfDayInformation */, &buf.SysTimeOfDayInfo,
-        sizeof(buf.SysTimeOfDayInfo), &len);
-    if (NT_SUCCESS(status) &&
-        len >= offsetof(union buf, SysTimeOfDayInfoHacked.BootTime) +
-                   sizeof(buf.SysTimeOfDayInfoHacked.BootTime) &&
-        buf.SysTimeOfDayInfoHacked.BootTime.QuadPart) {
-      bootid_collect(&bin, &buf.SysTimeOfDayInfoHacked.BootTime,
-                     sizeof(buf.SysTimeOfDayInfoHacked.BootTime));
-      got_boottime = true;
-    }
-
-    if (!got_boottime) {
-      uint64_t boottime = windows_bootime();
-      if (boottime) {
-        bootid_collect(&bin, &boottime, sizeof(boottime));
-        got_boottime = true;
-      }
-    }
-  }
-#endif /* Windows */
-
-#if defined(CTL_HW) && defined(HW_UUID)
-  if (!got_machineid) {
-    static const int mib[] = {CTL_HW, HW_UUID};
-    char buf[42];
-    size_t len = sizeof(buf);
-    if (sysctl(
-#ifdef SYSCTL_LEGACY_NONCONST_MIB
-            (int *)
-#endif
-                mib,
-            ARRAY_LENGTH(mib), &buf, &len, NULL, 0) == 0)
-      got_machineid = bootid_parse_uuid(&bin, buf, len);
-  }
-#endif /* CTL_HW && HW_UUID */
-
-#if defined(CTL_KERN) && defined(KERN_HOSTUUID)
-  if (!got_machineid) {
-    static const int mib[] = {CTL_KERN, KERN_HOSTUUID};
-    char buf[42];
-    size_t len = sizeof(buf);
-    if (sysctl(
-#ifdef SYSCTL_LEGACY_NONCONST_MIB
-            (int *)
-#endif
-                mib,
-            ARRAY_LENGTH(mib), &buf, &len, NULL, 0) == 0)
-      got_machineid = bootid_parse_uuid(&bin, buf, len);
-  }
-#endif /* CTL_KERN && KERN_HOSTUUID */
-
-#if defined(__NetBSD__)
-  if (!got_machineid) {
-    char buf[42];
-    size_t len = sizeof(buf);
-    if (sysctlbyname("machdep.dmi.system-uuid", buf, &len, NULL, 0) == 0)
-      got_machineid = bootid_parse_uuid(&bin, buf, len);
-  }
-#endif /* __NetBSD__ */
-
-#if _XOPEN_SOURCE_EXTENDED
-  if (!got_machineid) {
-    const int hostid = gethostid();
-    if (hostid > 0) {
-      bootid_collect(&bin, &hostid, sizeof(hostid));
-      got_machineid = true;
-    }
-  }
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-  if (!got_machineid) {
-  lack:
-    bin.x = bin.y = 0;
-    return bin;
-  }
-
-  /*--------------------------------------------------------------------------*/
-
-#if defined(CTL_KERN) && defined(KERN_BOOTTIME)
-  if (!got_boottime) {
-    static const int mib[] = {CTL_KERN, KERN_BOOTTIME};
-    struct timeval boottime;
-    size_t len = sizeof(boottime);
-    if (sysctl(
-#ifdef SYSCTL_LEGACY_NONCONST_MIB
-            (int *)
-#endif
-                mib,
-            ARRAY_LENGTH(mib), &boottime, &len, NULL, 0) == 0 &&
-        len == sizeof(boottime) && boottime.tv_sec) {
-      bootid_collect(&bin, &boottime, len);
-      got_boottime = true;
-    }
-  }
-#endif /* CTL_KERN && KERN_BOOTTIME */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-  if (!got_boottime) {
-    kstat_ctl_t *kc = kstat_open();
-    if (kc) {
-      kstat_t *kp = kstat_lookup(kc, "unix", 0, "system_misc");
-      if (kp && kstat_read(kc, kp, 0) != -1) {
-        kstat_named_t *kn = (kstat_named_t *)kstat_data_lookup(kp, "boot_time");
-        if (kn) {
-          switch (kn->data_type) {
-          case KSTAT_DATA_INT32:
-          case KSTAT_DATA_UINT32:
-            bootid_collect(&bin, &kn->value, sizeof(int32_t));
-            got_boottime = true;
-          case KSTAT_DATA_INT64:
-          case KSTAT_DATA_UINT64:
-            bootid_collect(&bin, &kn->value, sizeof(int64_t));
-            got_boottime = true;
-          }
-        }
-      }
-      kstat_close(kc);
-    }
-  }
-#endif /* SunOS / Solaris */
-
-#if _XOPEN_SOURCE_EXTENDED && defined(BOOT_TIME)
-  if (!got_boottime) {
-    setutxent();
-    const struct utmpx id = {.ut_type = BOOT_TIME};
-    const struct utmpx *entry = getutxid(&id);
-    if (entry) {
-      bootid_collect(&bin, entry, sizeof(*entry));
-      got_boottime = true;
-      while (unlikely((entry = getutxid(&id)) != nullptr)) {
-        /* have multiple reboot records, assuming we can distinguish next
-         * bootsession even if RTC is wrong or absent */
-        bootid_collect(&bin, entry, sizeof(*entry));
-        got_bootseq = true;
-      }
-    }
-    endutxent();
-  }
-#endif /* _XOPEN_SOURCE_EXTENDED && BOOT_TIME */
-
-  if (!got_bootseq) {
-    if (!got_boottime || !MDBX_TRUST_RTC)
-      goto lack;
-
-#if defined(_WIN32) || defined(_WIN64)
-    FILETIME now;
-    GetSystemTimeAsFileTime(&now);
-    if (0x1CCCCCC > now.dwHighDateTime)
-#else
-    struct timespec mono, real;
-    if (clock_gettime(CLOCK_MONOTONIC, &mono) ||
-        clock_gettime(CLOCK_REALTIME, &real) ||
-        /* wrong time, RTC is mad or absent */
-        1555555555l > real.tv_sec ||
-        /* seems no adjustment by RTC/NTP, i.e. a fake time */
-        real.tv_sec < mono.tv_sec || 1234567890l > real.tv_sec - mono.tv_sec ||
-        (real.tv_sec - mono.tv_sec) % 900u == 0)
-#endif
-      goto lack;
-  }
-
-  return bin;
-}
-/* This is CMake-template for libmdbx's version.c
- ******************************************************************************/
-
-
-#if MDBX_VERSION_MAJOR != 0 ||                             \
-    MDBX_VERSION_MINOR != 9
-#error "API version mismatch! Had `git fetch --tags` done?"
-#endif
-
-static const char sourcery[] = STRINGIFY(MDBX_BUILD_SOURCERY);
-
-__dll_export
-#ifdef __attribute_used__
-    __attribute_used__
-#elif defined(__GNUC__) || __has_attribute(__used__)
-    __attribute__((__used__))
-#endif
-#ifdef __attribute_externally_visible__
-        __attribute_externally_visible__
-#elif (defined(__GNUC__) && !defined(__clang__)) ||                            \
-    __has_attribute(__externally_visible__)
-    __attribute__((__externally_visible__))
-#endif
-    const struct MDBX_version_info mdbx_version = {
-        0,
-        9,
-        2,
-        136,
-        {"2021-01-30T02:28:12+03:00", "1ab2fa795a0dee8678b168ffcd961ca5a0fff7c5", "9f0ff865e860435b243d3d1e936e3067097a294f",
-         "v0.9.2-136-g9f0ff86"},
-        sourcery};
-
-__dll_export
-#ifdef __attribute_used__
-    __attribute_used__
-#elif defined(__GNUC__) || __has_attribute(__used__)
-    __attribute__((__used__))
-#endif
-#ifdef __attribute_externally_visible__
-        __attribute_externally_visible__
-#elif (defined(__GNUC__) && !defined(__clang__)) ||                            \
-    __has_attribute(__externally_visible__)
-    __attribute__((__externally_visible__))
-#endif
-    const char *const mdbx_sourcery_anchor = sourcery;
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-#if defined(_WIN32) || defined(_WIN64) /* Windows LCK-implementation */
-
-/* PREAMBLE FOR WINDOWS:
- *
- * We are not concerned for performance here.
- * If you are running Windows a performance could NOT be the goal.
- * Otherwise please use Linux. */
-
-
-static void mdbx_winnt_import(void);
-
-#if MDBX_BUILD_SHARED_LIBRARY
-#if MDBX_AVOID_CRT && defined(NDEBUG)
-/* DEBUG/CHECKED builds still require MSVC's CRT for runtime checks.
- *
- * Define dll's entry point only for Release build when NDEBUG is defined and
- * MDBX_AVOID_CRT=ON. if the entry point isn't defined then MSVC's will
- * automatically use DllMainCRTStartup() from CRT library, which also
- * automatically call DllMain() from our mdbx.dll */
-#pragma comment(linker, "/ENTRY:DllMain")
-#endif /* MDBX_AVOID_CRT */
-
-BOOL APIENTRY DllMain(HANDLE module, DWORD reason, LPVOID reserved)
-#else
-#if !MDBX_CONFIG_MANUAL_TLS_CALLBACK
-static
-#endif /* !MDBX_CONFIG_MANUAL_TLS_CALLBACK */
-    void NTAPI
-    mdbx_dll_handler(PVOID module, DWORD reason, PVOID reserved)
-#endif /* MDBX_BUILD_SHARED_LIBRARY */
-{
-  (void)reserved;
-  switch (reason) {
-  case DLL_PROCESS_ATTACH:
-    mdbx_winnt_import();
-    mdbx_rthc_global_init();
-    break;
-  case DLL_PROCESS_DETACH:
-    mdbx_rthc_global_dtor();
-    break;
-
-  case DLL_THREAD_ATTACH:
-    break;
-  case DLL_THREAD_DETACH:
-    mdbx_rthc_thread_dtor(module);
-    break;
-  }
-#if MDBX_BUILD_SHARED_LIBRARY
-  return TRUE;
-#endif
-}
-
-#if !MDBX_BUILD_SHARED_LIBRARY && !MDBX_CONFIG_MANUAL_TLS_CALLBACK
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(_MSC_VER)
-#  pragma const_seg(push)
-#  pragma data_seg(push)
-
-#  ifdef _WIN64
-     /* kick a linker to create the TLS directory if not already done */
-#    pragma comment(linker, "/INCLUDE:_tls_used")
-     /* Force some symbol references. */
-#    pragma comment(linker, "/INCLUDE:mdbx_tls_anchor")
-     /* specific const-segment for WIN64 */
-#    pragma const_seg(".CRT$XLB")
-     const
-#  else
-     /* kick a linker to create the TLS directory if not already done */
-#    pragma comment(linker, "/INCLUDE:__tls_used")
-     /* Force some symbol references. */
-#    pragma comment(linker, "/INCLUDE:_mdbx_tls_anchor")
-     /* specific data-segment for WIN32 */
-#    pragma data_seg(".CRT$XLB")
-#  endif
-
-   __declspec(allocate(".CRT$XLB")) PIMAGE_TLS_CALLBACK mdbx_tls_anchor = mdbx_dll_handler;
-#  pragma data_seg(pop)
-#  pragma const_seg(pop)
-
-#elif defined(__GNUC__)
-#  ifdef _WIN64
-     const
-#  endif
-   PIMAGE_TLS_CALLBACK mdbx_tls_anchor __attribute__((__section__(".CRT$XLB"), used)) = mdbx_dll_handler;
-#else
-#  error FIXME
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-#endif /* !MDBX_BUILD_SHARED_LIBRARY && !MDBX_CONFIG_MANUAL_TLS_CALLBACK */
-
-/*----------------------------------------------------------------------------*/
-
-#define LCK_SHARED 0
-#define LCK_EXCLUSIVE LOCKFILE_EXCLUSIVE_LOCK
-#define LCK_WAITFOR 0
-#define LCK_DONTWAIT LOCKFILE_FAIL_IMMEDIATELY
-
-static __inline BOOL flock(mdbx_filehandle_t fd, DWORD flags, uint64_t offset,
-                           size_t bytes) {
-  OVERLAPPED ov;
-  ov.hEvent = 0;
-  ov.Offset = (DWORD)offset;
-  ov.OffsetHigh = HIGH_DWORD(offset);
-  return LockFileEx(fd, flags, 0, (DWORD)bytes, HIGH_DWORD(bytes), &ov);
-}
-
-static __inline BOOL funlock(mdbx_filehandle_t fd, uint64_t offset,
-                             size_t bytes) {
-  return UnlockFile(fd, (DWORD)offset, HIGH_DWORD(offset), (DWORD)bytes,
-                    HIGH_DWORD(bytes));
-}
-
-/*----------------------------------------------------------------------------*/
-/* global `write` lock for write-txt processing,
- * exclusive locking both meta-pages) */
-
-#define LCK_MAXLEN (1u + (size_t)(MAXSSIZE_T))
-#define LCK_META_OFFSET 0
-#define LCK_META_LEN (MAX_PAGESIZE * NUM_METAS)
-#define LCK_BODY_OFFSET LCK_META_LEN
-#define LCK_BODY_LEN (LCK_MAXLEN - LCK_BODY_OFFSET)
-#define LCK_BODY LCK_BODY_OFFSET, LCK_BODY_LEN
-#define LCK_WHOLE 0, LCK_MAXLEN
-
-int mdbx_txn_lock(MDBX_env *env, bool dontwait) {
-  if (dontwait) {
-    if (!TryEnterCriticalSection(&env->me_windowsbug_lock))
-      return MDBX_BUSY;
-  } else {
-    __try {
-      EnterCriticalSection(&env->me_windowsbug_lock);
-    }
-    __except ((GetExceptionCode() ==
-                 0xC0000194 /* STATUS_POSSIBLE_DEADLOCK / EXCEPTION_POSSIBLE_DEADLOCK */)
-                    ? EXCEPTION_EXECUTE_HANDLER
-                    : EXCEPTION_CONTINUE_SEARCH) {
-      return ERROR_POSSIBLE_DEADLOCK;
-    }
-  }
-
-  if ((env->me_flags & MDBX_EXCLUSIVE) ||
-      flock(env->me_lazy_fd,
-            dontwait ? (LCK_EXCLUSIVE | LCK_DONTWAIT)
-                     : (LCK_EXCLUSIVE | LCK_WAITFOR),
-            LCK_BODY))
-    return MDBX_SUCCESS;
-  int rc = GetLastError();
-  LeaveCriticalSection(&env->me_windowsbug_lock);
-  return (!dontwait || rc != ERROR_LOCK_VIOLATION) ? rc : MDBX_BUSY;
-}
-
-void mdbx_txn_unlock(MDBX_env *env) {
-  int rc = (env->me_flags & MDBX_EXCLUSIVE)
-               ? TRUE
-               : funlock(env->me_lazy_fd, LCK_BODY);
-  LeaveCriticalSection(&env->me_windowsbug_lock);
-  if (!rc)
-    mdbx_panic("%s failed: err %u", __func__, GetLastError());
-}
-
-/*----------------------------------------------------------------------------*/
-/* global `read` lock for readers registration,
- * exclusive locking `mti_numreaders` (second) cacheline */
-
-#define LCK_LO_OFFSET 0
-#define LCK_LO_LEN offsetof(MDBX_lockinfo, mti_numreaders)
-#define LCK_UP_OFFSET LCK_LO_LEN
-#define LCK_UP_LEN (sizeof(MDBX_lockinfo) - LCK_UP_OFFSET)
-#define LCK_LOWER LCK_LO_OFFSET, LCK_LO_LEN
-#define LCK_UPPER LCK_UP_OFFSET, LCK_UP_LEN
-
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env) {
-  mdbx_srwlock_AcquireShared(&env->me_remap_guard);
-  if (env->me_lfd == INVALID_HANDLE_VALUE)
-    return MDBX_SUCCESS; /* readonly database in readonly filesystem */
-
-  /* transition from S-? (used) to S-E (locked),
-   * e.g. exclusive lock upper-part */
-  if ((env->me_flags & MDBX_EXCLUSIVE) ||
-      flock(env->me_lfd, LCK_EXCLUSIVE | LCK_WAITFOR, LCK_UPPER))
-    return MDBX_SUCCESS;
-
-  int rc = GetLastError();
-  mdbx_srwlock_ReleaseShared(&env->me_remap_guard);
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env) {
-  if (env->me_lfd != INVALID_HANDLE_VALUE) {
-    /* transition from S-E (locked) to S-? (used), e.g. unlock upper-part */
-    if ((env->me_flags & MDBX_EXCLUSIVE) == 0 &&
-        !funlock(env->me_lfd, LCK_UPPER))
-      mdbx_panic("%s failed: err %u", __func__, GetLastError());
-  }
-  mdbx_srwlock_ReleaseShared(&env->me_remap_guard);
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait) {
-  return flock(fd,
-               wait ? LCK_EXCLUSIVE | LCK_WAITFOR
-                    : LCK_EXCLUSIVE | LCK_DONTWAIT,
-               0, LCK_MAXLEN)
-             ? MDBX_SUCCESS
-             : GetLastError();
-}
-
-static int suspend_and_append(mdbx_handle_array_t **array,
-                              const DWORD ThreadId) {
-  const unsigned limit = (*array)->limit;
-  if ((*array)->count == limit) {
-    void *ptr = mdbx_realloc(
-        (limit > ARRAY_LENGTH((*array)->handles))
-            ? *array
-            : /* don't free initial array on the stack */ NULL,
-        sizeof(mdbx_handle_array_t) +
-            sizeof(HANDLE) * (limit * 2 - ARRAY_LENGTH((*array)->handles)));
-    if (!ptr)
-      return MDBX_ENOMEM;
-    if (limit == ARRAY_LENGTH((*array)->handles))
-      memcpy(ptr, *array, sizeof(mdbx_handle_array_t));
-    *array = (mdbx_handle_array_t *)ptr;
-    (*array)->limit = limit * 2;
-  }
-
-  HANDLE hThread = OpenThread(THREAD_SUSPEND_RESUME | THREAD_QUERY_INFORMATION,
-                              FALSE, ThreadId);
-  if (hThread == NULL)
-    return GetLastError();
-
-  if (SuspendThread(hThread) == -1) {
-    int err = GetLastError();
-    DWORD ExitCode;
-    if (err == /* workaround for Win10 UCRT bug */ ERROR_ACCESS_DENIED ||
-        !GetExitCodeThread(hThread, &ExitCode) || ExitCode != STILL_ACTIVE)
-      err = MDBX_SUCCESS;
-    CloseHandle(hThread);
-    return err;
-  }
-
-  (*array)->handles[(*array)->count++] = hThread;
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array) {
-  const uintptr_t CurrentTid = GetCurrentThreadId();
-  int rc;
-  if (env->me_lck) {
-    /* Scan LCK for threads of the current process */
-    const MDBX_reader *const begin = env->me_lck->mti_readers;
-    const MDBX_reader *const end =
-        begin + atomic_load32(&env->me_lck->mti_numreaders, mo_AcquireRelease);
-    const uintptr_t WriteTxnOwner = env->me_txn0 ? env->me_txn0->mt_owner : 0;
-    for (const MDBX_reader *reader = begin; reader < end; ++reader) {
-      if (reader->mr_pid.weak != env->me_pid || !reader->mr_tid.weak) {
-      skip_lck:
-        continue;
-      }
-      if (reader->mr_tid.weak == CurrentTid ||
-          reader->mr_tid.weak == WriteTxnOwner)
-        goto skip_lck;
-      if (env->me_flags & MDBX_NOTLS) {
-        /* Skip duplicates in no-tls mode */
-        for (const MDBX_reader *scan = reader; --scan >= begin;)
-          if (scan->mr_tid.weak == reader->mr_tid.weak)
-            goto skip_lck;
-      }
-
-      rc = suspend_and_append(array, (mdbx_tid_t)reader->mr_tid.weak);
-      if (rc != MDBX_SUCCESS) {
-      bailout_lck:
-        (void)mdbx_resume_threads_after_remap(*array);
-        return rc;
-      }
-    }
-    if (WriteTxnOwner && WriteTxnOwner != CurrentTid) {
-      rc = suspend_and_append(array, (mdbx_tid_t)WriteTxnOwner);
-      if (rc != MDBX_SUCCESS)
-        goto bailout_lck;
-    }
-  } else {
-    /* Without LCK (i.e. read-only mode).
-     * Walk through a snapshot of all running threads */
-    mdbx_assert(env,
-                env->me_txn0 == NULL || (env->me_flags & MDBX_EXCLUSIVE) != 0);
-    const HANDLE hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);
-    if (hSnapshot == INVALID_HANDLE_VALUE)
-      return GetLastError();
-
-    THREADENTRY32 entry;
-    entry.dwSize = sizeof(THREADENTRY32);
-
-    if (!Thread32First(hSnapshot, &entry)) {
-      rc = GetLastError();
-    bailout_toolhelp:
-      CloseHandle(hSnapshot);
-      (void)mdbx_resume_threads_after_remap(*array);
-      return rc;
-    }
-
-    do {
-      if (entry.th32OwnerProcessID != env->me_pid ||
-          entry.th32ThreadID == CurrentTid)
-        continue;
-
-      rc = suspend_and_append(array, entry.th32ThreadID);
-      if (rc != MDBX_SUCCESS)
-        goto bailout_toolhelp;
-
-    } while (Thread32Next(hSnapshot, &entry));
-
-    rc = GetLastError();
-    if (rc != ERROR_NO_MORE_FILES)
-      goto bailout_toolhelp;
-    CloseHandle(hSnapshot);
-  }
-
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array) {
-  int rc = MDBX_SUCCESS;
-  for (unsigned i = 0; i < array->count; ++i) {
-    const HANDLE hThread = array->handles[i];
-    if (ResumeThread(hThread) == -1) {
-      const int err = GetLastError();
-      DWORD ExitCode;
-      if (err != /* workaround for Win10 UCRT bug */ ERROR_ACCESS_DENIED &&
-          GetExitCodeThread(hThread, &ExitCode) && ExitCode == STILL_ACTIVE)
-        rc = err;
-    }
-    CloseHandle(hThread);
-  }
-  return rc;
-}
-
-/*----------------------------------------------------------------------------*/
-/* global `initial` lock for lockfile initialization,
- * exclusive/shared locking first cacheline */
-
-/* Briefly description of locking schema/algorithm:
- *  - Windows does not support upgrading or downgrading for file locking.
- *  - Therefore upgrading/downgrading is emulated by shared and exclusive
- *    locking of upper and lower halves.
- *  - In other words, we have FSM with possible 9 states,
- *    i.e. free/shared/exclusive x free/shared/exclusive == 9.
- *    Only 6 states of FSM are used, which 2 of ones are transitive.
- *
- * States:
- *   ?-?  = free, i.e. unlocked
- *   S-?  = used, i.e. shared lock
- *   E-?  = exclusive-read, i.e. operational exclusive
- *   ?-S
- *   ?-E  = middle (transitive state)
- *   S-S
- *   S-E  = locked (transitive state)
- *   E-S
- *   E-E  = exclusive-write, i.e. exclusive due (re)initialization
- *
- *  The mdbx_lck_seize() moves the locking-FSM from the initial free/unlocked
- *  state to the "exclusive write" (and returns MDBX_RESULT_TRUE) if possible,
- *  or to the "used" (and returns MDBX_RESULT_FALSE).
- *
- *  The mdbx_lck_downgrade() moves the locking-FSM from "exclusive write"
- *  state to the "used" (i.e. shared) state.
- *
- *  The mdbx_lck_upgrade() moves the locking-FSM from "used" (i.e. shared)
- *  state to the "exclusive write" state.
- */
-
-static void lck_unlock(MDBX_env *env) {
-  int err;
-
-  if (env->me_lfd != INVALID_HANDLE_VALUE) {
-    /* double `unlock` for robustly remove overlapped shared/exclusive locks */
-    while (funlock(env->me_lfd, LCK_LOWER))
-      ;
-    err = GetLastError();
-    assert(err == ERROR_NOT_LOCKED ||
-           (mdbx_RunningUnderWine() && err == ERROR_LOCK_VIOLATION));
-    (void)err;
-    SetLastError(ERROR_SUCCESS);
-
-    while (funlock(env->me_lfd, LCK_UPPER))
-      ;
-    err = GetLastError();
-    assert(err == ERROR_NOT_LOCKED ||
-           (mdbx_RunningUnderWine() && err == ERROR_LOCK_VIOLATION));
-    (void)err;
-    SetLastError(ERROR_SUCCESS);
-  }
-
-  if (env->me_lazy_fd != INVALID_HANDLE_VALUE) {
-    /* explicitly unlock to avoid latency for other processes (windows kernel
-     * releases such locks via deferred queues) */
-    while (funlock(env->me_lazy_fd, LCK_BODY))
-      ;
-    err = GetLastError();
-    assert(err == ERROR_NOT_LOCKED ||
-           (mdbx_RunningUnderWine() && err == ERROR_LOCK_VIOLATION));
-    (void)err;
-    SetLastError(ERROR_SUCCESS);
-
-    while (funlock(env->me_lazy_fd, LCK_WHOLE))
-      ;
-    err = GetLastError();
-    assert(err == ERROR_NOT_LOCKED ||
-           (mdbx_RunningUnderWine() && err == ERROR_LOCK_VIOLATION));
-    (void)err;
-    SetLastError(ERROR_SUCCESS);
-  }
-}
-
-/* Seize state as 'exclusive-write' (E-E and returns MDBX_RESULT_TRUE)
- * or as 'used' (S-? and returns MDBX_RESULT_FALSE).
- * Otherwise returns an error. */
-static int internal_seize_lck(HANDLE lfd) {
-  int rc;
-  assert(lfd != INVALID_HANDLE_VALUE);
-
-  /* 1) now on ?-? (free), get ?-E (middle) */
-  mdbx_jitter4testing(false);
-  if (!flock(lfd, LCK_EXCLUSIVE | LCK_WAITFOR, LCK_UPPER)) {
-    rc = GetLastError() /* 2) something went wrong, give up */;
-    mdbx_error("%s, err %u", "?-?(free) >> ?-E(middle)", rc);
-    return rc;
-  }
-
-  /* 3) now on ?-E (middle), try E-E (exclusive-write) */
-  mdbx_jitter4testing(false);
-  if (flock(lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_LOWER))
-    return MDBX_RESULT_TRUE /* 4) got E-E (exclusive-write), done */;
-
-  /* 5) still on ?-E (middle) */
-  rc = GetLastError();
-  mdbx_jitter4testing(false);
-  if (rc != ERROR_SHARING_VIOLATION && rc != ERROR_LOCK_VIOLATION) {
-    /* 6) something went wrong, give up */
-    if (!funlock(lfd, LCK_UPPER))
-      mdbx_panic("%s(%s) failed: err %u", __func__, "?-E(middle) >> ?-?(free)",
-                 GetLastError());
-    return rc;
-  }
-
-  /* 7) still on ?-E (middle), try S-E (locked) */
-  mdbx_jitter4testing(false);
-  rc = flock(lfd, LCK_SHARED | LCK_DONTWAIT, LCK_LOWER) ? MDBX_RESULT_FALSE
-                                                        : GetLastError();
-
-  mdbx_jitter4testing(false);
-  if (rc != MDBX_RESULT_FALSE)
-    mdbx_error("%s, err %u", "?-E(middle) >> S-E(locked)", rc);
-
-  /* 8) now on S-E (locked) or still on ?-E (middle),
-   *    transition to S-? (used) or ?-? (free) */
-  if (!funlock(lfd, LCK_UPPER))
-    mdbx_panic("%s(%s) failed: err %u", __func__,
-               "X-E(locked/middle) >> X-?(used/free)", GetLastError());
-
-  /* 9) now on S-? (used, DONE) or ?-? (free, FAILURE) */
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env) {
-  int rc;
-
-  assert(env->me_lazy_fd != INVALID_HANDLE_VALUE);
-  if (env->me_flags & MDBX_EXCLUSIVE)
-    return MDBX_RESULT_TRUE /* nope since files were must be opened
-                               non-shareable */
-        ;
-
-  if (env->me_lfd == INVALID_HANDLE_VALUE) {
-    /* LY: without-lck mode (e.g. on read-only filesystem) */
-    mdbx_jitter4testing(false);
-    if (!flock(env->me_lazy_fd, LCK_SHARED | LCK_DONTWAIT, LCK_WHOLE)) {
-      rc = GetLastError();
-      mdbx_error("%s, err %u", "without-lck", rc);
-      return rc;
-    }
-    return MDBX_RESULT_FALSE;
-  }
-
-  rc = internal_seize_lck(env->me_lfd);
-  mdbx_jitter4testing(false);
-  if (rc == MDBX_RESULT_TRUE && (env->me_flags & MDBX_RDONLY) == 0) {
-    /* Check that another process don't operates in without-lck mode.
-     * Doing such check by exclusive locking the body-part of db. Should be
-     * noted:
-     *  - we need an exclusive lock for do so;
-     *  - we can't lock meta-pages, otherwise other process could get an error
-     *    while opening db in valid (non-conflict) mode. */
-    if (!flock(env->me_lazy_fd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_BODY)) {
-      rc = GetLastError();
-      mdbx_error("%s, err %u", "lock-against-without-lck", rc);
-      mdbx_jitter4testing(false);
-      lck_unlock(env);
-    } else {
-      mdbx_jitter4testing(false);
-      if (!funlock(env->me_lazy_fd, LCK_BODY))
-        mdbx_panic("%s(%s) failed: err %u", __func__,
-                   "unlock-against-without-lck", GetLastError());
-    }
-  }
-
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env) {
-  /* Transite from exclusive-write state (E-E) to used (S-?) */
-  assert(env->me_lazy_fd != INVALID_HANDLE_VALUE);
-  assert(env->me_lfd != INVALID_HANDLE_VALUE);
-
-  if (env->me_flags & MDBX_EXCLUSIVE)
-    return MDBX_SUCCESS /* nope since files were must be opened non-shareable */
-        ;
-  /* 1) now at E-E (exclusive-write), transition to ?_E (middle) */
-  if (!funlock(env->me_lfd, LCK_LOWER))
-    mdbx_panic("%s(%s) failed: err %u", __func__,
-               "E-E(exclusive-write) >> ?-E(middle)", GetLastError());
-
-  /* 2) now at ?-E (middle), transition to S-E (locked) */
-  if (!flock(env->me_lfd, LCK_SHARED | LCK_DONTWAIT, LCK_LOWER)) {
-    int rc = GetLastError() /* 3) something went wrong, give up */;
-    mdbx_error("%s, err %u", "?-E(middle) >> S-E(locked)", rc);
-    return rc;
-  }
-
-  /* 4) got S-E (locked), continue transition to S-? (used) */
-  if (!funlock(env->me_lfd, LCK_UPPER))
-    mdbx_panic("%s(%s) failed: err %u", __func__, "S-E(locked) >> S-?(used)",
-               GetLastError());
-
-  return MDBX_SUCCESS /* 5) now at S-? (used), done */;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lck_upgrade(MDBX_env *env) {
-  /* Transite from used state (S-?) to exclusive-write (E-E) */
-  assert(env->me_lfd != INVALID_HANDLE_VALUE);
-
-  if (env->me_flags & MDBX_EXCLUSIVE)
-    return MDBX_SUCCESS /* nope since files were must be opened non-shareable */
-        ;
-
-  int rc;
-  /* 1) now on S-? (used), try S-E (locked) */
-  mdbx_jitter4testing(false);
-  if (!flock(env->me_lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_UPPER)) {
-    rc = GetLastError() /* 2) something went wrong, give up */;
-    mdbx_verbose("%s, err %u", "S-?(used) >> S-E(locked)", rc);
-    return rc;
-  }
-
-  /* 3) now on S-E (locked), transition to ?-E (middle) */
-  if (!funlock(env->me_lfd, LCK_LOWER))
-    mdbx_panic("%s(%s) failed: err %u", __func__, "S-E(locked) >> ?-E(middle)",
-               GetLastError());
-
-  /* 4) now on ?-E (middle), try E-E (exclusive-write) */
-  mdbx_jitter4testing(false);
-  if (!flock(env->me_lfd, LCK_EXCLUSIVE | LCK_DONTWAIT, LCK_LOWER)) {
-    rc = GetLastError() /* 5) something went wrong, give up */;
-    mdbx_verbose("%s, err %u", "?-E(middle) >> E-E(exclusive-write)", rc);
-    return rc;
-  }
-
-  return MDBX_SUCCESS /* 6) now at E-E (exclusive-write), done */;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag) {
-  (void)env;
-  (void)inprocess_neighbor;
-  (void)global_uniqueness_flag;
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor) {
-  /* LY: should unmap before releasing the locks to avoid race condition and
-   * STATUS_USER_MAPPED_FILE/ERROR_USER_MAPPED_FILE */
-  if (env->me_map)
-    mdbx_munmap(&env->me_dxb_mmap);
-  if (env->me_lck) {
-    const bool synced = env->me_lck_mmap.lck->mti_unsynced_pages.weak == 0;
-    mdbx_munmap(&env->me_lck_mmap);
-    if (synced && !inprocess_neighbor && env->me_lfd != INVALID_HANDLE_VALUE &&
-        mdbx_lck_upgrade(env) == MDBX_SUCCESS)
-      /* this will fail if LCK is used/mmapped by other process(es) */
-      mdbx_ftruncate(env->me_lfd, 0);
-  }
-  lck_unlock(env);
-  return MDBX_SUCCESS;
-}
-
-/*----------------------------------------------------------------------------*/
-/* reader checking (by pid) */
-
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env) {
-  (void)env;
-  return MDBX_SUCCESS;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env) {
-  (void)env;
-  return MDBX_SUCCESS;
-}
-
-/* Checks reader by pid.
- *
- * Returns:
- *   MDBX_RESULT_TRUE, if pid is live (unable to acquire lock)
- *   MDBX_RESULT_FALSE, if pid is dead (lock acquired)
- *   or otherwise the errcode. */
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid) {
-  (void)env;
-  HANDLE hProcess = OpenProcess(SYNCHRONIZE, FALSE, pid);
-  int rc;
-  if (likely(hProcess)) {
-    rc = WaitForSingleObject(hProcess, 0);
-    if (unlikely(rc == WAIT_FAILED))
-      rc = GetLastError();
-    CloseHandle(hProcess);
-  } else {
-    rc = GetLastError();
-  }
-
-  switch (rc) {
-  case ERROR_INVALID_PARAMETER:
-    /* pid seems invalid */
-    return MDBX_RESULT_FALSE;
-  case WAIT_OBJECT_0:
-    /* process just exited */
-    return MDBX_RESULT_FALSE;
-  case ERROR_ACCESS_DENIED:
-    /* The ERROR_ACCESS_DENIED would be returned for CSRSS-processes, etc.
-     * assume pid exists */
-    return MDBX_RESULT_TRUE;
-  case WAIT_TIMEOUT:
-    /* pid running */
-    return MDBX_RESULT_TRUE;
-  default:
-    /* failure */
-    return rc;
-  }
-}
-
-//----------------------------------------------------------------------------
-// Stub for slim read-write lock
-// Copyright (C) 1995-2002 Brad Wilson
-
-static void WINAPI stub_srwlock_Init(MDBX_srwlock *srwl) {
-  srwl->readerCount = srwl->writerCount = 0;
-}
-
-static void WINAPI stub_srwlock_AcquireShared(MDBX_srwlock *srwl) {
-  while (true) {
-    assert(srwl->writerCount >= 0 && srwl->readerCount >= 0);
-
-    //  If there's a writer already, spin without unnecessarily
-    //  interlocking the CPUs
-    if (srwl->writerCount != 0) {
-      YieldProcessor();
-      continue;
-    }
-
-    //  Add to the readers list
-    _InterlockedIncrement(&srwl->readerCount);
-
-    // Check for writers again (we may have been preempted). If
-    // there are no writers writing or waiting, then we're done.
-    if (srwl->writerCount == 0)
-      break;
-
-    // Remove from the readers list, spin, try again
-    _InterlockedDecrement(&srwl->readerCount);
-    YieldProcessor();
-  }
-}
-
-static void WINAPI stub_srwlock_ReleaseShared(MDBX_srwlock *srwl) {
-  assert(srwl->readerCount > 0);
-  _InterlockedDecrement(&srwl->readerCount);
-}
-
-static void WINAPI stub_srwlock_AcquireExclusive(MDBX_srwlock *srwl) {
-  while (true) {
-    assert(srwl->writerCount >= 0 && srwl->readerCount >= 0);
-
-    //  If there's a writer already, spin without unnecessarily
-    //  interlocking the CPUs
-    if (srwl->writerCount != 0) {
-      YieldProcessor();
-      continue;
-    }
-
-    // See if we can become the writer (expensive, because it inter-
-    // locks the CPUs, so writing should be an infrequent process)
-    if (_InterlockedExchange(&srwl->writerCount, 1) == 0)
-      break;
-  }
-
-  // Now we're the writer, but there may be outstanding readers.
-  // Spin until there aren't any more; new readers will wait now
-  // that we're the writer.
-  while (srwl->readerCount != 0) {
-    assert(srwl->writerCount >= 0 && srwl->readerCount >= 0);
-    YieldProcessor();
-  }
-}
-
-static void WINAPI stub_srwlock_ReleaseExclusive(MDBX_srwlock *srwl) {
-  assert(srwl->writerCount == 1 && srwl->readerCount >= 0);
-  srwl->writerCount = 0;
-}
-
-MDBX_srwlock_function mdbx_srwlock_Init, mdbx_srwlock_AcquireShared,
-    mdbx_srwlock_ReleaseShared, mdbx_srwlock_AcquireExclusive,
-    mdbx_srwlock_ReleaseExclusive;
-
-/*----------------------------------------------------------------------------*/
-
-#if 0  /* LY: unused for now */
-static DWORD WINAPI stub_DiscardVirtualMemory(PVOID VirtualAddress,
-                                              SIZE_T Size) {
-  return VirtualAlloc(VirtualAddress, Size, MEM_RESET, PAGE_NOACCESS)
-             ? ERROR_SUCCESS
-	  : GetLastError();
-}
-#endif /* unused for now */
-
-static uint64_t WINAPI stub_GetTickCount64(void) {
-  LARGE_INTEGER Counter, Frequency;
-  return (QueryPerformanceFrequency(&Frequency) &&
-          QueryPerformanceCounter(&Counter))
-             ? Counter.QuadPart * 1000ul / Frequency.QuadPart
-             : 0;
-}
-
-/*----------------------------------------------------------------------------*/
-#ifndef MDBX_ALLOY
-MDBX_NtExtendSection mdbx_NtExtendSection;
-MDBX_GetFileInformationByHandleEx mdbx_GetFileInformationByHandleEx;
-MDBX_GetVolumeInformationByHandleW mdbx_GetVolumeInformationByHandleW;
-MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-MDBX_SetFileInformationByHandle mdbx_SetFileInformationByHandle;
-MDBX_NtFsControlFile mdbx_NtFsControlFile;
-MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-MDBX_GetTickCount64 mdbx_GetTickCount64;
-MDBX_RegGetValueA mdbx_RegGetValueA;
-#if 0  /* LY: unused for now */
-MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-#endif /* unused for now */
-#endif /* MDBX_ALLOY */
-
-static void mdbx_winnt_import(void) {
-  const HINSTANCE hNtdll = GetModuleHandleA("ntdll.dll");
-
-#define GET_PROC_ADDR(dll, ENTRY)                                              \
-  mdbx_##ENTRY = (MDBX_##ENTRY)GetProcAddress(dll, #ENTRY)
-
-  if (GetProcAddress(hNtdll, "wine_get_version")) {
-    assert(mdbx_RunningUnderWine());
-  } else {
-    GET_PROC_ADDR(hNtdll, NtFsControlFile);
-    GET_PROC_ADDR(hNtdll, NtExtendSection);
-    assert(!mdbx_RunningUnderWine());
-  }
-
-  const HINSTANCE hKernel32dll = GetModuleHandleA("kernel32.dll");
-  GET_PROC_ADDR(hKernel32dll, GetFileInformationByHandleEx);
-  GET_PROC_ADDR(hKernel32dll, GetTickCount64);
-  if (!mdbx_GetTickCount64)
-    mdbx_GetTickCount64 = stub_GetTickCount64;
-  if (!mdbx_RunningUnderWine()) {
-    GET_PROC_ADDR(hKernel32dll, SetFileInformationByHandle);
-    GET_PROC_ADDR(hKernel32dll, GetVolumeInformationByHandleW);
-    GET_PROC_ADDR(hKernel32dll, GetFinalPathNameByHandleW);
-    GET_PROC_ADDR(hKernel32dll, PrefetchVirtualMemory);
-  }
-
-  const HINSTANCE hAdvapi32dll = GetModuleHandleA("advapi32.dll");
-  GET_PROC_ADDR(hAdvapi32dll, RegGetValueA);
-
-#if 0  /* LY: unused for now */
-  if (!mdbx_RunningUnderWine()) {
-    GET_PROC_ADDR(hKernel32dll, DiscardVirtualMemory);
-    GET_PROC_ADDR(hKernel32dll, OfferVirtualMemory);
-    GET_PROC_ADDR(hKernel32dll, ReclaimVirtualMemory);
-  }
-  if (!mdbx_DiscardVirtualMemory)
-    mdbx_DiscardVirtualMemory = stub_DiscardVirtualMemory;
-  if (!mdbx_OfferVirtualMemory)
-    mdbx_OfferVirtualMemory = stub_OfferVirtualMemory;
-  if (!mdbx_ReclaimVirtualMemory)
-    mdbx_ReclaimVirtualMemory = stub_ReclaimVirtualMemory;
-#endif /* unused for now */
-
-#undef GET_PROC_ADDR
-
-  const MDBX_srwlock_function init =
-      (MDBX_srwlock_function)GetProcAddress(hKernel32dll, "InitializeSRWLock");
-  if (init != NULL) {
-    mdbx_srwlock_Init = init;
-    mdbx_srwlock_AcquireShared = (MDBX_srwlock_function)GetProcAddress(
-        hKernel32dll, "AcquireSRWLockShared");
-    mdbx_srwlock_ReleaseShared = (MDBX_srwlock_function)GetProcAddress(
-        hKernel32dll, "ReleaseSRWLockShared");
-    mdbx_srwlock_AcquireExclusive = (MDBX_srwlock_function)GetProcAddress(
-        hKernel32dll, "AcquireSRWLockExclusive");
-    mdbx_srwlock_ReleaseExclusive = (MDBX_srwlock_function)GetProcAddress(
-        hKernel32dll, "ReleaseSRWLockExclusive");
-  } else {
-    mdbx_srwlock_Init = stub_srwlock_Init;
-    mdbx_srwlock_AcquireShared = stub_srwlock_AcquireShared;
-    mdbx_srwlock_ReleaseShared = stub_srwlock_ReleaseShared;
-    mdbx_srwlock_AcquireExclusive = stub_srwlock_AcquireExclusive;
-    mdbx_srwlock_ReleaseExclusive = stub_srwlock_ReleaseExclusive;
-  }
-}
-
-#endif /* Windows LCK-implementation */
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-#if !(defined(_WIN32) || defined(_WIN64)) /* !Windows LCK-implementation */
-
-#include <sys/sem.h>
-
-/*----------------------------------------------------------------------------*/
-/* global constructor/destructor */
-
-#if defined(__linux__) || defined(__gnu_linux__)
-
-#include <sys/utsname.h>
-
-#ifndef MDBX_ALLOY
-uint32_t mdbx_linux_kernel_version;
-bool mdbx_RunningOnWSL1;
-#endif /* MDBX_ALLOY */
-
-static __cold uint8_t probe_for_WSL(const char *tag) {
-  const char *const WSL = strstr(tag, "WSL");
-  if (WSL && WSL[3] >= '2' && WSL[3] <= '9')
-    return WSL[3] - '0';
-  const char *const wsl = strstr(tag, "wsl");
-  if (wsl && wsl[3] >= '2' && wsl[3] <= '9')
-    return wsl[3] - '0';
-  return (WSL || wsl || strcasestr(tag, "Microsoft")) ? 1 : 0;
-}
-
-#endif /* Linux */
-
-static __cold __attribute__((__constructor__)) void
-mdbx_global_constructor(void) {
-#if defined(__linux__) || defined(__gnu_linux__)
-  struct utsname buffer;
-  if (uname(&buffer) == 0) {
-    /* "Official" way of detecting WSL1 but not WSL2
-     * https://github.com/Microsoft/WSL/issues/423#issuecomment-221627364
-     *
-     * WARNING: False negative detection of WSL1 will result in DATA LOSS!
-     * So, the REQUIREMENTS for this code:
-     *  1. MUST detect WSL1 without false-negatives.
-     *  2. DESIRABLE detect WSL2 but without the risk of violating the first. */
-    mdbx_RunningOnWSL1 = probe_for_WSL(buffer.version) == 1 ||
-                         probe_for_WSL(buffer.sysname) == 1 ||
-                         probe_for_WSL(buffer.release) == 1;
-    int i = 0;
-    char *p = buffer.release;
-    while (*p && i < 4) {
-      if (*p >= '0' && *p <= '9') {
-        long number = strtol(p, &p, 10);
-        if (number > 0) {
-          if (number > 255)
-            number = 255;
-          mdbx_linux_kernel_version += number << (24 - i * 8);
-        }
-        ++i;
-      } else {
-        ++p;
-      }
-    }
-  }
-#endif /* Linux */
-
-  mdbx_rthc_global_init();
-}
-
-static __cold __attribute__((__destructor__)) void
-mdbx_global_destructor(void) {
-  mdbx_rthc_global_dtor();
-}
-
-/*----------------------------------------------------------------------------*/
-/* lck */
-
-/* Описание реализации блокировок для POSIX & Linux:
- *
- * lck-файл отображается в память, в нём организуется таблица читателей и
- * размещаются совместно используемые posix-мьютексы (futex). Посредством
- * этих мьютексов (см struct MDBX_lockinfo) реализуются:
- *  - Блокировка таблицы читателей для регистрации,
- *    т.е. функции mdbx_rdt_lock() и mdbx_rdt_unlock().
- *  - Блокировка БД для пишущих транзакций,
- *    т.е. функции mdbx_txn_lock() и mdbx_txn_unlock().
- *
- * Остальной функционал реализуется отдельно посредством файловых блокировок:
- *  - Первоначальный захват БД в режиме exclusive/shared и последующий перевод
- *    в операционный режим, функции mdbx_lck_seize() и mdbx_lck_downgrade().
- *  - Проверка присутствие процессов-читателей,
- *    т.е. функции mdbx_rpid_set(), mdbx_rpid_clear() и mdbx_rpid_check().
- *
- * Для блокировки файлов используется fcntl(F_SETLK), так как:
- *  - lockf() оперирует только эксклюзивной блокировкой и требует
- *    открытия файла в RW-режиме.
- *  - flock() не гарантирует атомарности при смене блокировок
- *    и оперирует только всем файлом целиком.
- *  - Для контроля процессов-читателей используются однобайтовые
- *    range-блокировки lck-файла посредством fcntl(F_SETLK). При этом
- *    в качестве позиции используется pid процесса-читателя.
- *  - Для первоначального захвата и shared/exclusive выполняется блокировка
- *    основного файла БД и при успехе lck-файла.
- *
- * ----------------------------------------------------------------------------
- * УДЕРЖИВАЕМЫЕ БЛОКИРОВКИ В ЗАВИСИМОСТИ ОТ РЕЖИМА И СОСТОЯНИЯ
- *
- * Эксклюзивный режим без lck-файла:
- *   = заблокирован весь dxb-файл посредством F_RDLCK или F_WRLCK,
- *     в зависимости от MDBX_RDONLY.
- *
- * Не-операционный режим на время пере-инициализации и разрушении lck-файла:
- *   = F_WRLCK блокировка первого байта lck-файла, другие процессы ждут её
- *     снятия при получении F_RDLCK через F_SETLKW.
- *   - блокировки dxb-файла могут меняться до снятие эксклюзивной блокировки
- *    lck-файла:
- *       + для НЕ-эксклюзивного режима блокировка pid-байта в dxb-файле
- *         посредством F_RDLCK или F_WRLCK, в зависимости от MDBX_RDONLY.
- *       + для ЭКСКЛЮЗИВНОГО режима блокировка pid-байта всего dxb-файла
- *         посредством F_RDLCK или F_WRLCK, в зависимости от MDBX_RDONLY.
- *
- * ОПЕРАЦИОННЫЙ режим с lck-файлом:
- *   = F_RDLCK блокировка первого байта lck-файла, другие процессы не могут
- *     получить F_WRLCK и таким образом видят что БД используется.
- *   + F_WRLCK блокировка pid-байта в clk-файле после первой транзакции чтения.
- *   + для НЕ-эксклюзивного режима блокировка pid-байта в dxb-файле
- *     посредством F_RDLCK или F_WRLCK, в зависимости от MDBX_RDONLY.
- *   + для ЭКСКЛЮЗИВНОГО режима блокировка pid-байта всего dxb-файла
- *     посредством F_RDLCK или F_WRLCK, в зависимости от MDBX_RDONLY.
- */
-
-#if MDBX_USE_OFDLOCKS
-static int op_setlk, op_setlkw, op_getlk;
-static void __cold choice_fcntl() {
-  assert(!op_setlk && !op_setlkw && !op_getlk);
-  if ((mdbx_runtime_flags & MDBX_DBG_LEGACY_MULTIOPEN) == 0
-#if defined(__linux__) || defined(__gnu_linux__)
-      && mdbx_linux_kernel_version >
-             0x030f0000 /* OFD locks are available since 3.15, but engages here
-                           only for 3.16 and later kernels (i.e. LTS) because
-                           of reliability reasons */
-#endif                  /* linux */
-  ) {
-    op_setlk = F_OFD_SETLK;
-    op_setlkw = F_OFD_SETLKW;
-    op_getlk = F_OFD_GETLK;
-    return;
-  }
-  op_setlk = F_SETLK;
-  op_setlkw = F_SETLKW;
-  op_getlk = F_GETLK;
-}
-#else
-#define op_setlk F_SETLK
-#define op_setlkw F_SETLKW
-#define op_getlk F_GETLK
-#endif /* MDBX_USE_OFDLOCKS */
-
-#ifndef OFF_T_MAX
-#define OFF_T_MAX                                                              \
-  ((sizeof(off_t) > 4 ? INT64_MAX : INT32_MAX) & ~(size_t)0xffff)
-#endif
-
-static int lck_op(mdbx_filehandle_t fd, int cmd, int lck, off_t offset,
-                  off_t len) {
-  mdbx_jitter4testing(true);
-  for (;;) {
-    struct flock lock_op;
-    memset(&lock_op, 0, sizeof(lock_op));
-    lock_op.l_type = lck;
-    lock_op.l_whence = SEEK_SET;
-    lock_op.l_start = offset;
-    lock_op.l_len = len;
-    int rc = fcntl(fd, cmd, &lock_op);
-    mdbx_jitter4testing(true);
-    if (rc != -1) {
-      if (cmd == op_getlk) {
-        /* Checks reader by pid. Returns:
-         *   MDBX_RESULT_TRUE   - if pid is live (reader holds a lock).
-         *   MDBX_RESULT_FALSE  - if pid is dead (a lock could be placed). */
-        return (lock_op.l_type == F_UNLCK) ? MDBX_RESULT_FALSE
-                                           : MDBX_RESULT_TRUE;
-      }
-      return MDBX_SUCCESS;
-    }
-    rc = errno;
-    if (rc != EINTR || cmd == op_setlkw) {
-      mdbx_assert(nullptr, MDBX_IS_ERROR(rc));
-      return rc;
-    }
-  }
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait) {
-#if MDBX_USE_OFDLOCKS
-  if (unlikely(op_setlk == 0))
-    choice_fcntl();
-#endif /* MDBX_USE_OFDLOCKS */
-  return lck_op(fd, wait ? op_setlkw : op_setlk, F_WRLCK, 0, OFF_T_MAX);
-}
-
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env) {
-  assert(env->me_lfd != INVALID_HANDLE_VALUE);
-  assert(env->me_pid > 0);
-  if (unlikely(mdbx_getpid() != env->me_pid))
-    return MDBX_PANIC;
-  return lck_op(env->me_lfd, op_setlk, F_WRLCK, env->me_pid, 1);
-}
-
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env) {
-  assert(env->me_lfd != INVALID_HANDLE_VALUE);
-  assert(env->me_pid > 0);
-  return lck_op(env->me_lfd, op_setlk, F_UNLCK, env->me_pid, 1);
-}
-
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid) {
-  assert(env->me_lfd != INVALID_HANDLE_VALUE);
-  assert(pid > 0);
-  return lck_op(env->me_lfd, op_getlk, F_WRLCK, pid, 1);
-}
-
-/*---------------------------------------------------------------------------*/
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc) {
-#if MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-  return sem_init(ipc, false, 1) ? errno : 0;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-  return pthread_mutex_init(ipc, nullptr);
-#else
-#error "FIXME"
-#endif
-}
-
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc) {
-#if MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-  return sem_destroy(ipc) ? errno : 0;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-  return pthread_mutex_destroy(ipc);
-#else
-#error "FIXME"
-#endif
-}
-#endif /* MDBX_LOCKING > MDBX_LOCKING_SYSV */
-
-static int check_fstat(MDBX_env *env) {
-  struct stat st;
-
-  int rc = MDBX_SUCCESS;
-  if (fstat(env->me_lazy_fd, &st)) {
-    rc = errno;
-    mdbx_error("fstat(%s), err %d", "DXB", rc);
-    return rc;
-  }
-
-  if (!S_ISREG(st.st_mode) || st.st_nlink < 1) {
-#ifdef EBADFD
-    rc = EBADFD;
-#else
-    rc = EPERM;
-#endif
-    mdbx_error("%s %s, err %d", "DXB",
-               (st.st_nlink < 1) ? "file was removed" : "not a regular file",
-               rc);
-    return rc;
-  }
-
-  if (st.st_size < (off_t)(MDBX_MIN_PAGESIZE * NUM_METAS)) {
-    mdbx_verbose("dxb-file is too short (%u), exclusive-lock needed",
-                 (unsigned)st.st_size);
-    rc = MDBX_RESULT_TRUE;
-  }
-
-  //----------------------------------------------------------------------------
-
-  if (fstat(env->me_lfd, &st)) {
-    rc = errno;
-    mdbx_error("fstat(%s), err %d", "LCK", rc);
-    return rc;
-  }
-
-  if (!S_ISREG(st.st_mode) || st.st_nlink < 1) {
-#ifdef EBADFD
-    rc = EBADFD;
-#else
-    rc = EPERM;
-#endif
-    mdbx_error("%s %s, err %d", "LCK",
-               (st.st_nlink < 1) ? "file was removed" : "not a regular file",
-               rc);
-    return rc;
-  }
-
-  /* Checking file size for detect the situation when we got the shared lock
-   * immediately after mdbx_lck_destroy(). */
-  if (st.st_size < (off_t)(sizeof(MDBX_lockinfo) + sizeof(MDBX_reader))) {
-    mdbx_verbose("lck-file is too short (%u), exclusive-lock needed",
-                 (unsigned)st.st_size);
-    rc = MDBX_RESULT_TRUE;
-  }
-
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int __cold mdbx_lck_seize(MDBX_env *env) {
-  assert(env->me_lazy_fd != INVALID_HANDLE_VALUE);
-  if (unlikely(mdbx_getpid() != env->me_pid))
-    return MDBX_PANIC;
-#if MDBX_USE_OFDLOCKS
-  if (unlikely(op_setlk == 0))
-    choice_fcntl();
-#endif /* MDBX_USE_OFDLOCKS */
-
-  int rc = MDBX_SUCCESS;
-#if defined(__linux__) || defined(__gnu_linux__)
-  if (unlikely(mdbx_RunningOnWSL1)) {
-    rc = ENOLCK /* No record locks available */;
-    mdbx_error("%s, err %u",
-               "WSL1 (Windows Subsystem for Linux) is mad and trouble-full, "
-               "injecting failure to avoid data loss",
-               rc);
-    return rc;
-  }
-#endif /* Linux */
-
-  if (env->me_lfd == INVALID_HANDLE_VALUE) {
-    /* LY: without-lck mode (e.g. exclusive or on read-only filesystem) */
-    rc =
-        lck_op(env->me_lazy_fd, op_setlk,
-               (env->me_flags & MDBX_RDONLY) ? F_RDLCK : F_WRLCK, 0, OFF_T_MAX);
-    if (rc != MDBX_SUCCESS) {
-      mdbx_error("%s, err %u", "without-lck", rc);
-      mdbx_assert(env, MDBX_IS_ERROR(rc));
-      return rc;
-    }
-    return MDBX_RESULT_TRUE /* Done: return with exclusive locking. */;
-  }
-#if defined(_POSIX_PRIORITY_SCHEDULING) && _POSIX_PRIORITY_SCHEDULING > 0
-  sched_yield();
-#endif
-
-retry:
-  if (rc == MDBX_RESULT_TRUE) {
-    rc = lck_op(env->me_lfd, op_setlk, F_UNLCK, 0, 1);
-    if (rc != MDBX_SUCCESS) {
-      mdbx_error("%s, err %u", "unlock-before-retry", rc);
-      mdbx_assert(env, MDBX_IS_ERROR(rc));
-      return rc;
-    }
-  }
-
-  /* Firstly try to get exclusive locking.  */
-  rc = lck_op(env->me_lfd, op_setlk, F_WRLCK, 0, 1);
-  if (rc == MDBX_SUCCESS) {
-    rc = check_fstat(env);
-    if (MDBX_IS_ERROR(rc))
-      return rc;
-
-  continue_dxb_exclusive:
-    rc =
-        lck_op(env->me_lazy_fd, op_setlk,
-               (env->me_flags & MDBX_RDONLY) ? F_RDLCK : F_WRLCK, 0, OFF_T_MAX);
-    if (rc == MDBX_SUCCESS)
-      return MDBX_RESULT_TRUE /* Done: return with exclusive locking. */;
-
-    int err = check_fstat(env);
-    if (MDBX_IS_ERROR(err))
-      return err;
-
-    /* the cause may be a collision with POSIX's file-lock recovery. */
-    if (!(rc == EAGAIN || rc == EACCES || rc == EBUSY || rc == EWOULDBLOCK ||
-          rc == EDEADLK)) {
-      mdbx_error("%s, err %u", "dxb-exclusive", rc);
-      mdbx_assert(env, MDBX_IS_ERROR(rc));
-      return rc;
-    }
-
-    /* Fallback to lck-shared */
-  } else if (!(rc == EAGAIN || rc == EACCES || rc == EBUSY ||
-               rc == EWOULDBLOCK || rc == EDEADLK)) {
-    mdbx_error("%s, err %u", "try-exclusive", rc);
-    mdbx_assert(env, MDBX_IS_ERROR(rc));
-    return rc;
-  }
-
-  /* Here could be one of two:
-   *  - mdbx_lck_destroy() from the another process was hold the lock
-   *    during a destruction.
-   *  - either mdbx_lck_seize() from the another process was got the exclusive
-   *    lock and doing initialization.
-   * For distinguish these cases will use size of the lck-file later. */
-
-  /* Wait for lck-shared now. */
-  /* Here may be await during transient processes, for instance until another
-   * competing process doesn't call lck_downgrade(). */
-  rc = lck_op(env->me_lfd, op_setlkw, F_RDLCK, 0, 1);
-  if (rc != MDBX_SUCCESS) {
-    mdbx_error("%s, err %u", "try-shared", rc);
-    mdbx_assert(env, MDBX_IS_ERROR(rc));
-    return rc;
-  }
-
-  rc = check_fstat(env);
-  if (rc == MDBX_RESULT_TRUE)
-    goto retry;
-  if (rc != MDBX_SUCCESS) {
-    mdbx_error("%s, err %u", "lck_fstat", rc);
-    return rc;
-  }
-
-  /* got shared, retry exclusive */
-  rc = lck_op(env->me_lfd, op_setlk, F_WRLCK, 0, 1);
-  if (rc == MDBX_SUCCESS)
-    goto continue_dxb_exclusive;
-
-  if (!(rc == EAGAIN || rc == EACCES || rc == EBUSY || rc == EWOULDBLOCK ||
-        rc == EDEADLK)) {
-    mdbx_error("%s, err %u", "try-exclusive", rc);
-    mdbx_assert(env, MDBX_IS_ERROR(rc));
-    return rc;
-  }
-
-  /* Lock against another process operating in without-lck or exclusive mode. */
-  rc =
-      lck_op(env->me_lazy_fd, op_setlk,
-             (env->me_flags & MDBX_RDONLY) ? F_RDLCK : F_WRLCK, env->me_pid, 1);
-  if (rc != MDBX_SUCCESS) {
-    mdbx_error("%s, err %u", "lock-against-without-lck", rc);
-    mdbx_assert(env, MDBX_IS_ERROR(rc));
-    return rc;
-  }
-
-  /* Done: return with shared locking. */
-  return MDBX_RESULT_FALSE;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env) {
-  assert(env->me_lfd != INVALID_HANDLE_VALUE);
-  if (unlikely(mdbx_getpid() != env->me_pid))
-    return MDBX_PANIC;
-
-  int rc = MDBX_SUCCESS;
-  if ((env->me_flags & MDBX_EXCLUSIVE) == 0) {
-    rc = lck_op(env->me_lazy_fd, op_setlk, F_UNLCK, 0, env->me_pid);
-    if (rc == MDBX_SUCCESS)
-      rc = lck_op(env->me_lazy_fd, op_setlk, F_UNLCK, env->me_pid + 1,
-                  OFF_T_MAX - env->me_pid - 1);
-  }
-  if (rc == MDBX_SUCCESS)
-    rc = lck_op(env->me_lfd, op_setlk, F_RDLCK, 0, 1);
-  if (unlikely(rc != 0)) {
-    mdbx_error("%s, err %u", "lck", rc);
-    assert(MDBX_IS_ERROR(rc));
-  }
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int __cold mdbx_lck_destroy(MDBX_env *env,
-                                               MDBX_env *inprocess_neighbor) {
-  if (unlikely(mdbx_getpid() != env->me_pid))
-    return MDBX_PANIC;
-
-  int rc = MDBX_SUCCESS;
-  struct stat lck_info;
-  if (env->me_lfd != INVALID_HANDLE_VALUE && !inprocess_neighbor &&
-      env->me_lck &&
-      /* try get exclusive access */
-      lck_op(env->me_lfd, op_setlk, F_WRLCK, 0, OFF_T_MAX) == 0 &&
-      /* if LCK was not removed */
-      fstat(env->me_lfd, &lck_info) == 0 && lck_info.st_nlink > 0 &&
-      lck_op(env->me_lazy_fd, op_setlk,
-             (env->me_flags & MDBX_RDONLY) ? F_RDLCK : F_WRLCK, 0,
-             OFF_T_MAX) == 0) {
-
-    mdbx_verbose("%p got exclusive, drown locks", (void *)env);
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-    if (env->me_sysv_ipc.semid != -1)
-      rc = semctl(env->me_sysv_ipc.semid, 2, IPC_RMID) ? errno : 0;
-#else
-    rc = mdbx_ipclock_destroy(&env->me_lck->mti_rlock);
-    if (rc == 0)
-      rc = mdbx_ipclock_destroy(&env->me_lck->mti_wlock);
-#endif /* MDBX_LOCKING */
-
-    mdbx_assert(env, rc == 0);
-    if (rc == 0) {
-      const bool synced = env->me_lck_mmap.lck->mti_unsynced_pages.weak == 0;
-      mdbx_munmap(&env->me_lck_mmap);
-      if (synced)
-        rc = ftruncate(env->me_lfd, 0) ? errno : 0;
-    }
-
-    mdbx_jitter4testing(false);
-  }
-
-  /* 1) POSIX's fcntl() locks (i.e. when op_setlk == F_SETLK) should be restored
-   * after file was closed.
-   *
-   * 2) File locks would be released (by kernel) while the file-descriptors will
-   * be closed. But to avoid false-positive EACCESS and EDEADLK from the kernel,
-   * locks should be released here explicitly with properly order. */
-
-  /* close dxb and restore lock */
-  if (env->me_dsync_fd != INVALID_HANDLE_VALUE) {
-    if (unlikely(close(env->me_dsync_fd) != 0) && rc == MDBX_SUCCESS)
-      rc = errno;
-    env->me_dsync_fd = INVALID_HANDLE_VALUE;
-  }
-  if (env->me_lazy_fd != INVALID_HANDLE_VALUE) {
-    if (unlikely(close(env->me_lazy_fd) != 0) && rc == MDBX_SUCCESS)
-      rc = errno;
-    env->me_lazy_fd = INVALID_HANDLE_VALUE;
-    if (op_setlk == F_SETLK && inprocess_neighbor && rc == MDBX_SUCCESS) {
-      /* restore file-lock */
-      rc = lck_op(
-          inprocess_neighbor->me_lazy_fd, F_SETLKW,
-          (inprocess_neighbor->me_flags & MDBX_RDONLY) ? F_RDLCK : F_WRLCK,
-          (inprocess_neighbor->me_flags & MDBX_EXCLUSIVE)
-              ? 0
-              : inprocess_neighbor->me_pid,
-          (inprocess_neighbor->me_flags & MDBX_EXCLUSIVE) ? OFF_T_MAX : 1);
-    }
-  }
-
-  /* close clk and restore locks */
-  if (env->me_lfd != INVALID_HANDLE_VALUE) {
-    if (unlikely(close(env->me_lfd) != 0) && rc == MDBX_SUCCESS)
-      rc = errno;
-    env->me_lfd = INVALID_HANDLE_VALUE;
-    if (op_setlk == F_SETLK && inprocess_neighbor && rc == MDBX_SUCCESS) {
-      /* restore file-locks */
-      rc = lck_op(inprocess_neighbor->me_lfd, F_SETLKW, F_RDLCK, 0, 1);
-      if (rc == MDBX_SUCCESS && inprocess_neighbor->me_live_reader)
-        rc = mdbx_rpid_set(inprocess_neighbor);
-    }
-  }
-
-  if (inprocess_neighbor && rc != MDBX_SUCCESS)
-    inprocess_neighbor->me_flags |= MDBX_FATAL_ERROR;
-  return rc;
-}
-
-/*---------------------------------------------------------------------------*/
-
-MDBX_INTERNAL_FUNC int __cold mdbx_lck_init(MDBX_env *env,
-                                            MDBX_env *inprocess_neighbor,
-                                            int global_uniqueness_flag) {
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  int semid = -1;
-  /* don't initialize semaphores twice */
-  (void)inprocess_neighbor;
-  if (global_uniqueness_flag == MDBX_RESULT_TRUE) {
-    struct stat st;
-    if (fstat(env->me_lazy_fd, &st))
-      return errno;
-  sysv_retry_create:
-    semid = semget(env->me_sysv_ipc.key, 2,
-                   IPC_CREAT | IPC_EXCL |
-                       (st.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO)));
-    if (unlikely(semid == -1)) {
-      int err = errno;
-      if (err != EEXIST)
-        return err;
-
-      /* remove and re-create semaphore set */
-      semid = semget(env->me_sysv_ipc.key, 2, 0);
-      if (semid == -1) {
-        err = errno;
-        if (err != ENOENT)
-          return err;
-        goto sysv_retry_create;
-      }
-      if (semctl(semid, 2, IPC_RMID)) {
-        err = errno;
-        if (err != EIDRM)
-          return err;
-      }
-      goto sysv_retry_create;
-    }
-
-    unsigned short val_array[2] = {1, 1};
-    if (semctl(semid, 2, SETALL, val_array))
-      return errno;
-  } else {
-    semid = semget(env->me_sysv_ipc.key, 2, 0);
-    if (semid == -1)
-      return errno;
-
-    /* check read & write access */
-    struct semid_ds data[2];
-    if (semctl(semid, 2, IPC_STAT, data) || semctl(semid, 2, IPC_SET, data))
-      return errno;
-  }
-
-  env->me_sysv_ipc.semid = semid;
-  return MDBX_SUCCESS;
-
-#elif MDBX_LOCKING == MDBX_LOCKING_FUTEX
-  (void)inprocess_neighbor;
-  if (global_uniqueness_flag != MDBX_RESULT_TRUE)
-    return MDBX_SUCCESS;
-#error "FIXME: Not implemented"
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-
-  /* don't initialize semaphores twice */
-  (void)inprocess_neighbor;
-  if (global_uniqueness_flag == MDBX_RESULT_TRUE) {
-    if (sem_init(&env->me_lck->mti_rlock, true, 1))
-      return errno;
-    if (sem_init(&env->me_lck->mti_wlock, true, 1))
-      return errno;
-  }
-  return MDBX_SUCCESS;
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-  if (inprocess_neighbor)
-    return MDBX_SUCCESS /* don't need any initialization for mutexes
-      if LCK already opened/used inside current process */
-        ;
-
-    /* FIXME: Unfortunately, there is no other reliable way but to long testing
-     * on each platform. On the other hand, behavior like FreeBSD is incorrect
-     * and we can expect it to be rare. Moreover, even on FreeBSD without
-     * additional in-process initialization, the probability of an problem
-     * occurring is vanishingly small, and the symptom is a return of EINVAL
-     * while locking a mutex. In other words, in the worst case, the problem
-     * results in an EINVAL error at the start of the transaction, but NOT data
-     * loss, nor database corruption, nor other fatal troubles. Thus, the code
-     * below I am inclined to think the workaround for erroneous platforms (like
-     * FreeBSD), rather than a defect of libmdbx. */
-#if defined(__FreeBSD__)
-  /* seems that shared mutexes on FreeBSD required in-process initialization */
-  (void)global_uniqueness_flag;
-#else
-  /* shared mutexes on many other platforms (including Darwin and Linux's
-   * futexes) doesn't need any addition in-process initialization */
-  if (global_uniqueness_flag != MDBX_RESULT_TRUE)
-    return MDBX_SUCCESS;
-#endif
-
-  pthread_mutexattr_t ma;
-  int rc = pthread_mutexattr_init(&ma);
-  if (rc)
-    return rc;
-
-  rc = pthread_mutexattr_setpshared(&ma, PTHREAD_PROCESS_SHARED);
-  if (rc)
-    goto bailout;
-
-#if MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#if defined(PTHREAD_MUTEX_ROBUST) || defined(pthread_mutexattr_setrobust)
-  rc = pthread_mutexattr_setrobust(&ma, PTHREAD_MUTEX_ROBUST);
-#elif defined(PTHREAD_MUTEX_ROBUST_NP) ||                                      \
-    defined(pthread_mutexattr_setrobust_np)
-  rc = pthread_mutexattr_setrobust_np(&ma, PTHREAD_MUTEX_ROBUST_NP);
-#elif _POSIX_THREAD_PROCESS_SHARED < 200809L
-  rc = pthread_mutexattr_setrobust_np(&ma, PTHREAD_MUTEX_ROBUST_NP);
-#else
-  rc = pthread_mutexattr_setrobust(&ma, PTHREAD_MUTEX_ROBUST);
-#endif
-  if (rc)
-    goto bailout;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_POSIX2008 */
-
-#if defined(_POSIX_THREAD_PRIO_INHERIT) && _POSIX_THREAD_PRIO_INHERIT >= 0 &&  \
-    !defined(MDBX_SAFE4QEMU)
-  rc = pthread_mutexattr_setprotocol(&ma, PTHREAD_PRIO_INHERIT);
-  if (rc == ENOTSUP)
-    rc = pthread_mutexattr_setprotocol(&ma, PTHREAD_PRIO_NONE);
-  if (rc && rc != ENOTSUP)
-    goto bailout;
-#endif /* PTHREAD_PRIO_INHERIT */
-
-  rc = pthread_mutexattr_settype(&ma, PTHREAD_MUTEX_ERRORCHECK);
-  if (rc && rc != ENOTSUP)
-    goto bailout;
-
-  rc = pthread_mutex_init(&env->me_lck->mti_rlock, &ma);
-  if (rc)
-    goto bailout;
-  rc = pthread_mutex_init(&env->me_lck->mti_wlock, &ma);
-
-bailout:
-  pthread_mutexattr_destroy(&ma);
-  return rc;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING > 0 */
-}
-
-static int __cold mdbx_ipclock_failed(MDBX_env *env, mdbx_ipclock_t *ipc,
-                                      const int err) {
-  int rc = err;
-#if MDBX_LOCKING == MDBX_LOCKING_POSIX2008 || MDBX_LOCKING == MDBX_LOCKING_SYSV
-  if (err == EOWNERDEAD) {
-    /* We own the mutex. Clean up after dead previous owner. */
-
-    const bool rlocked = (env->me_lck && ipc == &env->me_lck->mti_rlock);
-    rc = MDBX_SUCCESS;
-    if (!rlocked) {
-      if (unlikely(env->me_txn)) {
-        /* env is hosed if the dead thread was ours */
-        env->me_flags |= MDBX_FATAL_ERROR;
-        env->me_txn = NULL;
-        rc = MDBX_PANIC;
-      }
-    }
-    mdbx_warning("%clock owner died, %s", (rlocked ? 'r' : 'w'),
-                 (rc ? "this process' env is hosed" : "recovering"));
-
-    int check_rc = mdbx_cleanup_dead_readers(env, rlocked, NULL);
-    check_rc = (check_rc == MDBX_SUCCESS) ? MDBX_RESULT_TRUE : check_rc;
-
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-    rc = (rc == MDBX_SUCCESS) ? check_rc : rc;
-#else
-#if defined(PTHREAD_MUTEX_ROBUST) || defined(pthread_mutex_consistent)
-    int mreco_rc = pthread_mutex_consistent(ipc);
-#elif defined(PTHREAD_MUTEX_ROBUST_NP) || defined(pthread_mutex_consistent_np)
-    int mreco_rc = pthread_mutex_consistent_np(ipc);
-#elif _POSIX_THREAD_PROCESS_SHARED < 200809L
-    int mreco_rc = pthread_mutex_consistent_np(ipc);
-#else
-    int mreco_rc = pthread_mutex_consistent(ipc);
-#endif
-    check_rc = (mreco_rc == 0) ? check_rc : mreco_rc;
-
-    if (unlikely(mreco_rc))
-      mdbx_error("lock recovery failed, %s", mdbx_strerror(mreco_rc));
-
-    rc = (rc == MDBX_SUCCESS) ? check_rc : rc;
-    if (MDBX_IS_ERROR(rc))
-      pthread_mutex_unlock(ipc);
-#endif /* MDBX_LOCKING == MDBX_LOCKING_POSIX2008 */
-    return rc;
-  }
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001
-  (void)ipc;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-  (void)ipc;
-#elif MDBX_LOCKING == MDBX_LOCKING_FUTEX
-#ifdef _MSC_VER
-#pragma message("warning: TODO")
-#else
-#warning "TODO"
-#endif
-  (void)ipc;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-  mdbx_error("mutex (un)lock failed, %s", mdbx_strerror(err));
-  if (rc != EDEADLK)
-    env->me_flags |= MDBX_FATAL_ERROR;
-  return rc;
-}
-
-static int mdbx_ipclock_lock(MDBX_env *env, mdbx_ipclock_t *ipc,
-                             const bool dont_wait) {
-#if MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                  \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-  int rc = dont_wait ? pthread_mutex_trylock(ipc) : pthread_mutex_lock(ipc);
-  rc = (rc == EBUSY && dont_wait) ? MDBX_BUSY : rc;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-  int rc = MDBX_SUCCESS;
-  if (dont_wait) {
-    if (sem_trywait(ipc)) {
-      rc = errno;
-      if (rc == EAGAIN)
-        rc = MDBX_BUSY;
-    }
-  } else if (sem_wait(ipc))
-    rc = errno;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-  struct sembuf op = {.sem_num = (ipc != env->me_wlock),
-                      .sem_op = -1,
-                      .sem_flg = dont_wait ? IPC_NOWAIT | SEM_UNDO : SEM_UNDO};
-  int rc;
-  if (semop(env->me_sysv_ipc.semid, &op, 1)) {
-    rc = errno;
-    if (dont_wait && rc == EAGAIN)
-      rc = MDBX_BUSY;
-  } else {
-    rc = *ipc ? EOWNERDEAD : MDBX_SUCCESS;
-    *ipc = env->me_pid;
-  }
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-  if (unlikely(rc != MDBX_SUCCESS && rc != MDBX_BUSY))
-    rc = mdbx_ipclock_failed(env, ipc, rc);
-  return rc;
-}
-
-static int mdbx_ipclock_unlock(MDBX_env *env, mdbx_ipclock_t *ipc) {
-#if MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                  \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-  int rc = pthread_mutex_unlock(ipc);
-  (void)env;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-  int rc = sem_post(ipc) ? errno : MDBX_SUCCESS;
-  (void)env;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-  if (unlikely(*ipc != (pid_t)env->me_pid))
-    return EPERM;
-  *ipc = 0;
-  struct sembuf op = {
-      .sem_num = (ipc != env->me_wlock), .sem_op = 1, .sem_flg = SEM_UNDO};
-  int rc = semop(env->me_sysv_ipc.semid, &op, 1) ? errno : MDBX_SUCCESS;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env) {
-  mdbx_trace("%s", ">>");
-  mdbx_jitter4testing(true);
-  int rc = mdbx_ipclock_lock(env, &env->me_lck->mti_rlock, false);
-  mdbx_trace("<< rc %d", rc);
-  return rc;
-}
-
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env) {
-  mdbx_trace("%s", ">>");
-  int rc = mdbx_ipclock_unlock(env, &env->me_lck->mti_rlock);
-  mdbx_trace("<< rc %d", rc);
-  if (unlikely(rc != MDBX_SUCCESS))
-    mdbx_panic("%s() failed: err %d\n", __func__, rc);
-  mdbx_jitter4testing(true);
-}
-
-int mdbx_txn_lock(MDBX_env *env, bool dont_wait) {
-  mdbx_trace("%swait %s", dont_wait ? "dont-" : "", ">>");
-  mdbx_jitter4testing(true);
-  int rc = mdbx_ipclock_lock(env, env->me_wlock, dont_wait);
-  mdbx_trace("<< rc %d", rc);
-  return MDBX_IS_ERROR(rc) ? rc : MDBX_SUCCESS;
-}
-
-void mdbx_txn_unlock(MDBX_env *env) {
-  mdbx_trace("%s", ">>");
-  int rc = mdbx_ipclock_unlock(env, env->me_wlock);
-  mdbx_trace("<< rc %d", rc);
-  if (unlikely(rc != MDBX_SUCCESS))
-    mdbx_panic("%s() failed: err %d\n", __func__, rc);
-  mdbx_jitter4testing(true);
-}
-
-#else
-#ifdef _MSC_VER
-#pragma warning(disable : 4206) /* nonstandard extension used: translation     \
-                                   unit is empty */
-#endif                          /* _MSC_VER (warnings) */
-#endif                          /* !Windows LCK-implementation */
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx.c++ b/plugins/Dbx_mdbx/src/libmdbx/mdbx.c++
deleted file mode 100644
index e29b579cef..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx.c++
+++ /dev/null
@@ -1,4657 +0,0 @@
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_ALLOY 1
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h++"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-//
-// Copyright (c) 2020-2021, Leonid Yuriev <leo@yuriev.ru>.
-// SPDX-License-Identifier: Apache-2.0
-//
-// Non-inline part of the libmdbx C++ API (preliminary)
-//
-
-#ifdef _MSC_VER
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-
-
-
-#include <atomic>
-#include <cctype> // for isxdigit(), etc
-#include <system_error>
-
-namespace {
-
-#if 0 /* Unused for now */
-
-class trouble_location {
-
-#ifndef TROUBLE_PROVIDE_LINENO
-#define TROUBLE_PROVIDE_LINENO 1
-#endif
-
-#ifndef TROUBLE_PROVIDE_CONDITION
-#define TROUBLE_PROVIDE_CONDITION 1
-#endif
-
-#ifndef TROUBLE_PROVIDE_FUNCTION
-#define TROUBLE_PROVIDE_FUNCTION 1
-#endif
-
-#ifndef TROUBLE_PROVIDE_FILENAME
-#define TROUBLE_PROVIDE_FILENAME 1
-#endif
-
-#if TROUBLE_PROVIDE_LINENO
-  const unsigned line_;
-#endif
-#if TROUBLE_PROVIDE_CONDITION
-  const char *const condition_;
-#endif
-#if TROUBLE_PROVIDE_FUNCTION
-  const char *const function_;
-#endif
-#if TROUBLE_PROVIDE_FILENAME
-  const char *const filename_;
-#endif
-
-public:
-  MDBX_CXX11_CONSTEXPR trouble_location(unsigned line, const char *condition,
-                                   const char *function, const char *filename)
-      :
-#if TROUBLE_PROVIDE_LINENO
-        line_(line)
-#endif
-#if TROUBLE_PROVIDE_CONDITION
-        ,
-        condition_(condition)
-#endif
-#if TROUBLE_PROVIDE_FUNCTION
-        ,
-        function_(function)
-#endif
-#if TROUBLE_PROVIDE_FILENAME
-        ,
-        filename_(filename)
-#endif
-  {
-#if !TROUBLE_PROVIDE_LINENO
-    (void)line;
-#endif
-#if !TROUBLE_PROVIDE_CONDITION
-    (void)condition;
-#endif
-#if !TROUBLE_PROVIDE_FUNCTION
-    (void)function;
-#endif
-#if !TROUBLE_PROVIDE_FILENAME
-    (void)filename;
-#endif
-  }
-
-  trouble_location(const trouble_location &&) = delete;
-
-  unsigned line() const {
-#if TROUBLE_PROVIDE_LINENO
-    return line_;
-#else
-    return 0;
-#endif
-  }
-
-  const char *condition() const {
-#if TROUBLE_PROVIDE_CONDITION
-    return condition_;
-#else
-    return "";
-#endif
-  }
-
-  const char *function() const {
-#if TROUBLE_PROVIDE_FUNCTION
-    return function_;
-#else
-    return "";
-#endif
-  }
-
-  const char *filename() const {
-#if TROUBLE_PROVIDE_FILENAME
-    return filename_;
-#else
-    return "";
-#endif
-  }
-};
-
-//------------------------------------------------------------------------------
-
-__cold std::string format_va(const char *fmt, va_list ap) {
-  va_list ones;
-  va_copy(ones, ap);
-#ifdef _MSC_VER
-  int needed = _vscprintf(fmt, ap);
-#else
-  int needed = vsnprintf(nullptr, 0, fmt, ap);
-#endif
-  assert(needed >= 0);
-  std::string result;
-  result.reserve(size_t(needed + 1));
-  result.resize(size_t(needed), '\0');
-  assert(int(result.capacity()) > needed);
-  int actual = vsnprintf(const_cast<char *>(result.data()), result.capacity(),
-                         fmt, ones);
-  assert(actual == needed);
-  (void)actual;
-  va_end(ones);
-  return result;
-}
-
-__cold std::string format(const char *fmt, ...) {
-  va_list ap;
-  va_start(ap, fmt);
-  std::string result = format_va(fmt, ap);
-  va_end(ap);
-  return result;
-}
-
-class bug : public std::runtime_error {
-  const trouble_location &location_;
-
-public:
-  bug(const trouble_location &) noexcept;
-  /* temporary workaround for "private field 'FOO' is not used" from CLANG
-   * and for "function 'BAR' was declared but never referenced" from LCC. */
-#ifndef __LCC__
-  const trouble_location &location() const noexcept { return location_; }
-#endif
-  virtual ~bug() noexcept;
-};
-
-__cold bug::bug(const trouble_location &location) noexcept
-    : std::runtime_error(format("mdbx.bug: %s.%s at %s:%u", location.function(),
-                                location.condition(), location.filename(),
-                                location.line())),
-      location_(location) {}
-
-__cold bug::~bug() noexcept {}
-
-[[noreturn]] __cold void raise_bug(const trouble_location &what_and_where) {
-  throw bug(what_and_where);
-}
-
-#define RAISE_BUG(line, condition, function, file)                             \
-  do {                                                                         \
-    static MDBX_CXX11_CONSTEXPR_VAR trouble_location bug(line, condition,      \
-                                                         function, file);      \
-    raise_bug(bug);                                                            \
-  } while (0)
-
-#define ENSURE(condition)                                                      \
-  do                                                                           \
-    if (MDBX_UNLIKELY(!(condition)))                                           \
-      RAISE_BUG(__LINE__, #condition, __func__, __FILE__);                     \
-  while (0)
-
-#define NOT_IMPLEMENTED()                                                      \
-  RAISE_BUG(__LINE__, "not_implemented", __func__, __FILE__);
-
-#endif /* Unused*/
-
-//------------------------------------------------------------------------------
-
-template <typename PATH> struct path_to_pchar {
-  const std::string str;
-  path_to_pchar(const PATH &path) : str(path.generic_string()) {}
-  operator const char *() const { return str.c_str(); }
-};
-
-template <typename PATH> PATH pchar_to_path(const char *c_str) {
-  return PATH(c_str);
-}
-
-template <> struct path_to_pchar<std::string> {
-  const char *const ptr;
-  path_to_pchar(const std::string &path) : ptr(path.c_str()) {}
-  operator const char *() const { return ptr; }
-};
-
-#if defined(_WIN32) || defined(_WIN64)
-
-template <> struct path_to_pchar<std::wstring> {
-  std::string str;
-  path_to_pchar(const std::wstring &path) {
-    if (!path.empty()) {
-      const int chars =
-          WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, path.data(),
-                              int(path.size()), nullptr, 0, nullptr, nullptr);
-      if (chars == 0)
-        mdbx::error::throw_exception(GetLastError());
-      str.append(chars, '\0');
-      WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, path.data(),
-                          int(path.size()), const_cast<char *>(str.data()),
-                          chars, nullptr, nullptr);
-    }
-  }
-  operator const char *() const { return str.c_str(); }
-};
-
-template <> std::wstring pchar_to_path<std::wstring>(const char *c_str) {
-  std::wstring wstr;
-  if (c_str && *c_str) {
-    const int chars = MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, c_str,
-                                          int(strlen(c_str)), nullptr, 0);
-    if (chars == 0)
-      mdbx::error::throw_exception(GetLastError());
-    wstr.append(chars, '\0');
-    MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, c_str,
-                        int(strlen(c_str)), const_cast<wchar_t *>(wstr.data()),
-                        chars);
-  }
-  return wstr;
-}
-
-#endif /* Windows */
-
-} // namespace
-
-//------------------------------------------------------------------------------
-
-namespace mdbx {
-
-[[noreturn]] __cold void throw_max_length_exceeded() {
-  throw std::length_error(
-      "mdbx:: exceeded the maximal length of data/slice/buffer");
-}
-
-[[noreturn]] __cold void throw_too_small_target_buffer() {
-  throw std::length_error("mdbx:: the target buffer is too small");
-}
-
-[[noreturn]] __cold void throw_out_range() {
-  throw std::out_of_range("mdbx:: slice or buffer method was called with "
-                          "an argument that exceeds the length");
-}
-
-__cold exception::exception(const ::mdbx::error &error) noexcept
-    : base(error.what()), error_(error) {}
-
-__cold exception::~exception() noexcept {}
-
-static std::atomic_int fatal_countdown;
-
-__cold fatal::fatal(const ::mdbx::error &error) noexcept : base(error) {
-  ++fatal_countdown;
-}
-
-__cold fatal::~fatal() noexcept {
-  if (--fatal_countdown == 0)
-    std::terminate();
-}
-
-#define DEFINE_EXCEPTION(NAME)                                                 \
-  __cold NAME::NAME(const ::mdbx::error &rc) : exception(rc) {}                \
-  __cold NAME::~NAME() noexcept {}
-
-DEFINE_EXCEPTION(bad_map_id)
-DEFINE_EXCEPTION(bad_transaction)
-DEFINE_EXCEPTION(bad_value_size)
-DEFINE_EXCEPTION(db_corrupted)
-DEFINE_EXCEPTION(db_full)
-DEFINE_EXCEPTION(db_invalid)
-DEFINE_EXCEPTION(db_too_large)
-DEFINE_EXCEPTION(db_unable_extend)
-DEFINE_EXCEPTION(db_version_mismatch)
-DEFINE_EXCEPTION(db_wanna_write_for_recovery)
-DEFINE_EXCEPTION(incompatible_operation)
-DEFINE_EXCEPTION(internal_page_full)
-DEFINE_EXCEPTION(internal_problem)
-DEFINE_EXCEPTION(key_exists)
-DEFINE_EXCEPTION(key_mismatch)
-DEFINE_EXCEPTION(max_maps_reached)
-DEFINE_EXCEPTION(max_readers_reached)
-DEFINE_EXCEPTION(multivalue)
-DEFINE_EXCEPTION(no_data)
-DEFINE_EXCEPTION(not_found)
-DEFINE_EXCEPTION(operation_not_permitted)
-DEFINE_EXCEPTION(permission_denied_or_not_writeable)
-DEFINE_EXCEPTION(reader_slot_busy)
-DEFINE_EXCEPTION(remote_media)
-DEFINE_EXCEPTION(something_busy)
-DEFINE_EXCEPTION(thread_mismatch)
-DEFINE_EXCEPTION(transaction_full)
-DEFINE_EXCEPTION(transaction_overlapping)
-
-#undef DEFINE_EXCEPTION
-
-__cold const char *error::what() const noexcept {
-  if (is_mdbx_error())
-    return mdbx_liberr2str(code());
-
-  switch (code()) {
-#define ERROR_CASE(CODE)                                                       \
-  case CODE:                                                                   \
-    return STRINGIFY(CODE)
-    ERROR_CASE(MDBX_ENODATA);
-    ERROR_CASE(MDBX_EINVAL);
-    ERROR_CASE(MDBX_EACCESS);
-    ERROR_CASE(MDBX_ENOMEM);
-    ERROR_CASE(MDBX_EROFS);
-    ERROR_CASE(MDBX_ENOSYS);
-    ERROR_CASE(MDBX_EIO);
-    ERROR_CASE(MDBX_EPERM);
-    ERROR_CASE(MDBX_EINTR);
-    ERROR_CASE(MDBX_ENOFILE);
-    ERROR_CASE(MDBX_EREMOTE);
-#undef ERROR_CASE
-  default:
-    return "SYSTEM";
-  }
-}
-
-__cold std::string error::message() const {
-  char buf[1024];
-  const char *msg = ::mdbx_strerror_r(code(), buf, sizeof(buf));
-  return std::string(msg ? msg : "unknown");
-}
-
-[[noreturn]] __cold void error::panic(const char *context,
-                                      const char *func) const noexcept {
-  assert(code() != MDBX_SUCCESS);
-  ::mdbx_panic("mdbx::%s.%s(): \"%s\" (%d)", context, func, what(), code());
-  std::terminate();
-}
-
-__cold void error::throw_exception() const {
-  switch (code()) {
-  case MDBX_EINVAL:
-    throw std::invalid_argument("mdbx");
-  case MDBX_ENOMEM:
-    throw std::bad_alloc();
-  case MDBX_SUCCESS:
-    static_assert(MDBX_SUCCESS == MDBX_RESULT_FALSE, "WTF?");
-    throw std::logic_error("MDBX_SUCCESS (MDBX_RESULT_FALSE)");
-  case MDBX_RESULT_TRUE:
-    throw std::logic_error("MDBX_RESULT_TRUE");
-#define CASE_EXCEPTION(NAME, CODE)                                             \
-  case CODE:                                                                   \
-    throw NAME(code())
-    CASE_EXCEPTION(bad_map_id, MDBX_BAD_DBI);
-    CASE_EXCEPTION(bad_transaction, MDBX_BAD_TXN);
-    CASE_EXCEPTION(bad_value_size, MDBX_BAD_VALSIZE);
-    CASE_EXCEPTION(db_corrupted, MDBX_CORRUPTED);
-    CASE_EXCEPTION(db_corrupted, MDBX_CURSOR_FULL); /* branch-pages loop */
-    CASE_EXCEPTION(db_corrupted, MDBX_PAGE_NOTFOUND);
-    CASE_EXCEPTION(db_full, MDBX_MAP_FULL);
-    CASE_EXCEPTION(db_invalid, MDBX_INVALID);
-    CASE_EXCEPTION(db_too_large, MDBX_TOO_LARGE);
-    CASE_EXCEPTION(db_unable_extend, MDBX_UNABLE_EXTEND_MAPSIZE);
-    CASE_EXCEPTION(db_version_mismatch, MDBX_VERSION_MISMATCH);
-    CASE_EXCEPTION(db_wanna_write_for_recovery, MDBX_WANNA_RECOVERY);
-    CASE_EXCEPTION(fatal, MDBX_EBADSIGN);
-    CASE_EXCEPTION(fatal, MDBX_PANIC);
-    CASE_EXCEPTION(incompatible_operation, MDBX_INCOMPATIBLE);
-    CASE_EXCEPTION(internal_page_full, MDBX_PAGE_FULL);
-    CASE_EXCEPTION(internal_problem, MDBX_PROBLEM);
-    CASE_EXCEPTION(key_mismatch, MDBX_EKEYMISMATCH);
-    CASE_EXCEPTION(max_maps_reached, MDBX_DBS_FULL);
-    CASE_EXCEPTION(max_readers_reached, MDBX_READERS_FULL);
-    CASE_EXCEPTION(multivalue, MDBX_EMULTIVAL);
-    CASE_EXCEPTION(no_data, MDBX_ENODATA);
-    CASE_EXCEPTION(not_found, MDBX_NOTFOUND);
-    CASE_EXCEPTION(operation_not_permitted, MDBX_EPERM);
-    CASE_EXCEPTION(permission_denied_or_not_writeable, MDBX_EACCESS);
-    CASE_EXCEPTION(reader_slot_busy, MDBX_BAD_RSLOT);
-    CASE_EXCEPTION(remote_media, MDBX_EREMOTE);
-    CASE_EXCEPTION(something_busy, MDBX_BUSY);
-    CASE_EXCEPTION(thread_mismatch, MDBX_THREAD_MISMATCH);
-    CASE_EXCEPTION(transaction_full, MDBX_TXN_FULL);
-    CASE_EXCEPTION(transaction_overlapping, MDBX_TXN_OVERLAPPING);
-#undef CASE_EXCEPTION
-  default:
-    if (is_mdbx_error())
-      throw exception(*this);
-    throw std::system_error(std::error_code(code(), std::system_category()));
-  }
-}
-
-//------------------------------------------------------------------------------
-
-bool slice::is_printable(bool disable_utf8) const noexcept {
-  enum : byte {
-    LS = 4,                     // shift for UTF8 sequence length
-    P_ = 1 << LS,               // printable ASCII flag
-    N_ = 0,                     // non-printable ASCII
-    second_range_mask = P_ - 1, // mask for range flag
-    r80_BF = 0,                 // flag for UTF8 2nd byte range
-    rA0_BF = 1,                 // flag for UTF8 2nd byte range
-    r80_9F = 2,                 // flag for UTF8 2nd byte range
-    r90_BF = 3,                 // flag for UTF8 2nd byte range
-    r80_8F = 4,                 // flag for UTF8 2nd byte range
-
-    // valid utf-8 byte sequences
-    // http://www.unicode.org/versions/Unicode6.0.0/ch03.pdf - page 94
-    //                        Code               | Bytes  |        |        |
-    //                        Points             | 1st    | 2nd    | 3rd    |4th
-    //                       --------------------|--------|--------|--------|---
-    C2 = 2 << LS | r80_BF, // U+000080..U+0007FF | C2..DF | 80..BF |        |
-    E0 = 3 << LS | rA0_BF, // U+000800..U+000FFF | E0     | A0..BF | 80..BF |
-    E1 = 3 << LS | r80_BF, // U+001000..U+00CFFF | E1..EC | 80..BF | 80..BF |
-    ED = 3 << LS | r80_9F, // U+00D000..U+00D7FF | ED     | 80..9F | 80..BF |
-    EE = 3 << LS | r80_BF, // U+00E000..U+00FFFF | EE..EF | 80..BF | 80..BF |
-    F0 = 4 << LS | r90_BF, // U+010000..U+03FFFF | F0     | 90..BF | 80..BF |...
-    F1 = 4 << LS | r80_BF, // U+040000..U+0FFFFF | F1..F3 | 80..BF | 80..BF |...
-    F4 = 4 << LS | r80_BF, // U+100000..U+10FFFF | F4     | 80..8F | 80..BF |...
-  };
-
-  static const byte range_from[] = {0x80, 0xA0, 0x80, 0x90, 0x80};
-  static const byte range_to[] = {0xBF, 0xBF, 0x9F, 0xBF, 0x8F};
-
-  static const byte map[256] = {
-      //  1   2   3   4   5   6   7   8   9   a   b   c   d   e   f
-      N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, // 00
-      N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, N_, // 10
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // 20
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // 30
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // 40
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // 50
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // 60
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, N_, // 70
-      N_, N_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, N_, P_, N_, // 80
-      N_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, N_, P_, P_, // 90
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // a0
-      P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, // b0
-      P_, P_, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, // c0
-      C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, C2, // df
-      E0, E1, E1, E1, E1, E1, E1, E1, E1, E1, E1, E1, E1, ED, EE, EE, // e0
-      F0, F1, F1, F1, F4, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_, P_  // f0
-  };
-
-  if (length() < 1)
-    return false;
-
-  auto src = byte_ptr();
-  const auto end = src + length();
-  if (MDBX_UNLIKELY(disable_utf8)) {
-    do
-      if (MDBX_UNLIKELY((P_ & map[*src]) == 0))
-        return false;
-    while (++src < end);
-    return true;
-  }
-
-  do {
-    const auto bits = map[*src];
-    const auto second_from = range_from[bits & second_range_mask];
-    const auto second_to = range_to[bits & second_range_mask];
-    switch (bits >> LS) {
-    default:
-      return false;
-    case 1:
-      src += 1;
-      continue;
-    case 2:
-      if (unlikely(src + 1 >= end))
-        return false;
-      if (unlikely(src[1] < second_from || src[1] > second_to))
-        return false;
-      src += 2;
-      continue;
-    case 3:
-      if (unlikely(src + 3 >= end))
-        return false;
-      if (unlikely(src[1] < second_from || src[1] > second_to))
-        return false;
-      if (unlikely(src[2] < 0x80 || src[2] > 0xBF))
-        return false;
-      src += 3;
-      continue;
-    case 4:
-      if (unlikely(src + 4 >= end))
-        return false;
-      if (unlikely(src[1] < second_from || src[1] > second_to))
-        return false;
-      if (unlikely(src[2] < 0x80 || src[2] > 0xBF))
-        return false;
-      if (unlikely(src[3] < 0x80 || src[3] > 0xBF))
-        return false;
-      src += 4;
-      continue;
-    }
-  } while (src < end);
-
-  return true;
-}
-
-//------------------------------------------------------------------------------
-
-char *slice::to_hex(char *__restrict dest, size_t dest_size, bool uppercase,
-                    unsigned wrap_width) const {
-  if (MDBX_UNLIKELY(to_hex_bytes(wrap_width) > dest_size))
-    throw_too_small_target_buffer();
-
-  auto src = byte_ptr();
-  const char alphabase = (uppercase ? 'A' : 'a') - 10;
-  auto line = dest;
-  for (const auto end = src + length(); src != end; ++src) {
-    const int8_t hi = *src >> 4;
-    const int8_t lo = *src & 15;
-    dest[0] = char(alphabase + hi + (((hi - 10) >> 7) & -7));
-    dest[1] = char(alphabase + lo + (((lo - 10) >> 7) & -7));
-    dest += 2;
-    if (wrap_width && size_t(dest - line) >= wrap_width) {
-      *dest = '\n';
-      line = ++dest;
-    }
-  }
-  return dest;
-}
-
-byte *slice::from_hex(byte *__restrict dest, size_t dest_size,
-                      bool ignore_spaces) const {
-  if (MDBX_UNLIKELY(length() % 2 && !ignore_spaces))
-    throw std::domain_error(
-        "mdbx::from_hex:: odd length of hexadecimal string");
-  if (MDBX_UNLIKELY(from_hex_bytes() > dest_size))
-    throw_too_small_target_buffer();
-
-  auto src = byte_ptr();
-  for (auto left = length(); left > 0;) {
-    if (MDBX_UNLIKELY(*src <= ' ') &&
-        MDBX_LIKELY(ignore_spaces && isspace(*src))) {
-      ++src;
-      --left;
-      continue;
-    }
-
-    if (MDBX_UNLIKELY(left < 1 || !isxdigit(src[0]) || !isxdigit(src[1])))
-      throw std::domain_error("mdbx::from_hex:: invalid hexadecimal string");
-
-    int8_t hi = src[0];
-    hi = (hi | 0x20) - 'a';
-    hi += 10 + ((hi >> 7) & 7);
-
-    int8_t lo = src[1];
-    lo = (lo | 0x20) - 'a';
-    lo += 10 + ((lo >> 7) & 7);
-
-    *dest++ = hi << 4 | lo;
-    src += 2;
-    left -= 2;
-  }
-  return dest;
-}
-
-bool slice::is_hex(bool ignore_spaces) const noexcept {
-  if (MDBX_UNLIKELY(length() % 2 && !ignore_spaces))
-    return false;
-
-  bool got = false;
-  auto src = byte_ptr();
-  for (auto left = length(); left > 0;) {
-    if (MDBX_UNLIKELY(*src <= ' ') &&
-        MDBX_LIKELY(ignore_spaces && isspace(*src))) {
-      ++src;
-      --left;
-      continue;
-    }
-
-    if (MDBX_UNLIKELY(left < 1 || !isxdigit(src[0]) || !isxdigit(src[1])))
-      return false;
-
-    got = true;
-    src += 2;
-    left -= 2;
-  }
-  return got;
-}
-
-//------------------------------------------------------------------------------
-
-enum : signed char {
-  OO /* ASCII NUL */ = -8,
-  EQ /* BASE64 '=' pad */ = -4,
-  SP /* SPACE */ = -2,
-  IL /* invalid */ = -1
-};
-
-static const byte b58_alphabet[58] = {
-    '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F',
-    'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
-    'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'm',
-    'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'};
-
-#ifndef bswap64
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-static inline uint64_t bswap64(uint64_t v) noexcept {
-#if __GNUC_PREREQ(4, 4) || __CLANG_PREREQ(4, 0) ||                             \
-    __has_builtin(__builtin_bswap64)
-  return __builtin_bswap64(v);
-#elif defined(_MSC_VER) && !defined(__clang__)
-  return _byteswap_uint64(v);
-#elif defined(__bswap_64)
-  return __bswap_64(v);
-#elif defined(bswap_64)
-  return bswap_64(v);
-#else
-  return v << 56 | v >> 56 | ((v << 40) & UINT64_C(0x00ff000000000000)) |
-         ((v << 24) & UINT64_C(0x0000ff0000000000)) |
-         ((v << 8) & UINT64_C(0x000000ff00000000)) |
-         ((v >> 8) & UINT64_C(0x00000000ff000000)) |
-         ((v >> 24) & UINT64_C(0x0000000000ff0000)) |
-         ((v >> 40) & UINT64_C(0x000000000000ff00));
-#endif
-}
-#endif /* __BYTE_ORDER__ */
-#endif /* ifdef bswap64 */
-
-static inline char b58_8to11(uint64_t &v) noexcept {
-  const unsigned i = unsigned(v % 58);
-  v /= 58;
-  return b58_alphabet[i];
-}
-
-char *slice::to_base58(char *__restrict dest, size_t dest_size,
-                       unsigned wrap_width) const {
-  if (MDBX_UNLIKELY(to_base58_bytes(wrap_width) > dest_size))
-    throw_too_small_target_buffer();
-
-  auto src = byte_ptr();
-  size_t left = length();
-  auto line = dest;
-  while (MDBX_LIKELY(left > 7)) {
-    left -= 8;
-    uint64_t v;
-    std::memcpy(&v, src, 8);
-    src += 8;
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    v = bswap64(v);
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-    dest[10] = b58_8to11(v);
-    dest[9] = b58_8to11(v);
-    dest[8] = b58_8to11(v);
-    dest[7] = b58_8to11(v);
-    dest[6] = b58_8to11(v);
-    dest[5] = b58_8to11(v);
-    dest[4] = b58_8to11(v);
-    dest[3] = b58_8to11(v);
-    dest[2] = b58_8to11(v);
-    dest[1] = b58_8to11(v);
-    dest[0] = b58_8to11(v);
-    assert(v == 0);
-    dest += 11;
-    if (wrap_width && size_t(dest - line) >= wrap_width) {
-      *dest = '\n';
-      line = ++dest;
-    }
-  }
-
-  if (left) {
-    uint64_t v = 0;
-    unsigned parrots = 31;
-    do {
-      v = (v << 8) + *src++;
-      parrots += 43;
-    } while (--left);
-
-    auto ptr = dest += parrots >> 5;
-    do {
-      *--ptr = b58_8to11(v);
-      parrots -= 32;
-    } while (parrots > 31);
-    assert(v == 0);
-  }
-
-  return dest;
-}
-
-const signed char b58_map[256] = {
-    //   1   2   3   4   5   6   7   8   9   a   b   c   d   e   f
-    OO, IL, IL, IL, IL, IL, IL, IL, IL, SP, SP, SP, SP, SP, IL, IL, // 00
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 10
-    SP, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 20
-    IL, 0,  1,  2,  3,  4,  5,  6,  7,  8,  IL, IL, IL, IL, IL, IL, // 30
-    IL, 9,  10, 11, 12, 13, 14, 15, 16, IL, 17, 18, 19, 20, 21, IL, // 40
-    22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, IL, IL, IL, IL, IL, // 50
-    IL, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, IL, 44, 45, 46, // 60
-    47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, IL, IL, IL, IL, IL, // 70
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 80
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 90
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // a0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // b0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // c0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // d0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // e0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL  // f0
-};
-
-static inline signed char b58_11to8(uint64_t &v, const byte c) noexcept {
-  const signed char m = b58_map[c];
-  v = v * 58 + m;
-  return m;
-}
-
-byte *slice::from_base58(byte *__restrict dest, size_t dest_size,
-                         bool ignore_spaces) const {
-  if (MDBX_UNLIKELY(from_base58_bytes() > dest_size))
-    throw_too_small_target_buffer();
-
-  auto src = byte_ptr();
-  for (auto left = length(); left > 0;) {
-    if (MDBX_UNLIKELY(isspace(*src)) && ignore_spaces) {
-      ++src;
-      --left;
-      continue;
-    }
-
-    if (MDBX_LIKELY(left > 10)) {
-      uint64_t v = 0;
-      if (MDBX_UNLIKELY((b58_11to8(v, src[0]) | b58_11to8(v, src[1]) |
-                         b58_11to8(v, src[2]) | b58_11to8(v, src[3]) |
-                         b58_11to8(v, src[4]) | b58_11to8(v, src[5]) |
-                         b58_11to8(v, src[6]) | b58_11to8(v, src[7]) |
-                         b58_11to8(v, src[8]) | b58_11to8(v, src[9]) |
-                         b58_11to8(v, src[10])) < 0))
-        goto bailout;
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-      v = bswap64(v);
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-      std::memcpy(dest, &v, 8);
-      dest += 8;
-      src += 11;
-      left -= 11;
-      continue;
-    }
-
-    constexpr unsigned invalid_length_mask = 1 << 1 | 1 << 4 | 1 << 8;
-    if (invalid_length_mask & (1 << left))
-      goto bailout;
-
-    uint64_t v = 1;
-    unsigned parrots = 0;
-    do {
-      if (MDBX_UNLIKELY(b58_11to8(v, *src++) < 0))
-        goto bailout;
-      parrots += 32;
-    } while (--left);
-
-    auto ptr = dest += parrots / 43;
-    do {
-      *--ptr = byte(v);
-      v >>= 8;
-    } while (v > 255);
-    break;
-  }
-  return dest;
-
-bailout:
-  throw std::domain_error("mdbx::from_base58:: invalid base58 string");
-}
-
-bool slice::is_base58(bool ignore_spaces) const noexcept {
-  bool got = false;
-  auto src = byte_ptr();
-  for (auto left = length(); left > 0;) {
-    if (MDBX_UNLIKELY(*src <= ' ') &&
-        MDBX_LIKELY(ignore_spaces && isspace(*src))) {
-      ++src;
-      --left;
-      continue;
-    }
-
-    if (MDBX_LIKELY(left > 10)) {
-      if (MDBX_UNLIKELY((b58_map[src[0]] | b58_map[src[1]] | b58_map[src[2]] |
-                         b58_map[src[3]] | b58_map[src[4]] | b58_map[src[5]] |
-                         b58_map[src[6]] | b58_map[src[7]] | b58_map[src[8]] |
-                         b58_map[src[9]] | b58_map[src[10]]) < 0))
-        return false;
-      src += 11;
-      left -= 11;
-      got = true;
-      continue;
-    }
-
-    constexpr unsigned invalid_length_mask = 1 << 1 | 1 << 4 | 1 << 8;
-    if (invalid_length_mask & (1 << left))
-      return false;
-
-    do
-      if (MDBX_UNLIKELY(b58_map[*src++] < 0))
-        return false;
-    while (--left);
-    got = true;
-    break;
-  }
-  return got;
-}
-
-//------------------------------------------------------------------------------
-
-static inline void b64_3to4(const byte x, const byte y, const byte z,
-                            char *__restrict dest) noexcept {
-  static const byte alphabet[64] = {
-      'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
-      'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
-      'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
-      'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
-      '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};
-  dest[0] = alphabet[(x & 0xfc) >> 2];
-  dest[1] = alphabet[((x & 0x03) << 4) + ((y & 0xf0) >> 4)];
-  dest[2] = alphabet[((y & 0x0f) << 2) + ((z & 0xc0) >> 6)];
-  dest[3] = alphabet[z & 0x3f];
-}
-
-char *slice::to_base64(char *__restrict dest, size_t dest_size,
-                       unsigned wrap_width) const {
-  if (MDBX_UNLIKELY(to_base64_bytes(wrap_width) > dest_size))
-    throw_too_small_target_buffer();
-
-  auto src = byte_ptr();
-  size_t left = length();
-  auto line = dest;
-  while (true) {
-    switch (left) {
-    default:
-      MDBX_CXX20_LIKELY left -= 3;
-      b64_3to4(src[0], src[1], src[2], dest);
-      dest += 4;
-      src += 3;
-      if (wrap_width && size_t(dest - line) >= wrap_width) {
-        *dest = '\n';
-        line = ++dest;
-      }
-      continue;
-    case 2:
-      b64_3to4(src[0], 0, 0, dest);
-      dest[2] = dest[3] = '=';
-      return dest + 4;
-    case 1:
-      b64_3to4(src[0], src[1], 0, dest);
-      dest[3] = '=';
-      return dest + 4;
-    case 0:
-      return dest;
-    }
-  }
-}
-
-static const signed char b64_map[256] = {
-    //   1   2   3   4   5   6   7   8   9   a   b   c   d   e   f
-    OO, IL, IL, IL, IL, IL, IL, IL, IL, SP, SP, SP, SP, SP, IL, IL, // 00
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 10
-    SP, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, 62, IL, IL, IL, 63, // 20
-    52, 53, 54, 55, 56, 57, 58, 59, 60, 61, IL, IL, IL, EQ, IL, IL, // 30
-    IL, 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, // 40
-    15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, IL, IL, IL, IL, IL, // 50
-    IL, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, // 60
-    41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, IL, IL, IL, IL, IL, // 70
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 80
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // 90
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // a0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // b0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // c0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // d0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, // e0
-    IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL, IL  // f0
-};
-
-static inline signed char b64_4to3(signed char a, signed char b, signed char c,
-                                   signed char d,
-                                   byte *__restrict dest) noexcept {
-  dest[0] = byte((a << 2) + ((b & 0x30) >> 4));
-  dest[1] = byte(((b & 0xf) << 4) + ((c & 0x3c) >> 2));
-  dest[2] = byte(((c & 0x3) << 6) + d);
-  return a | b | c | d;
-}
-
-byte *slice::from_base64(byte *__restrict dest, size_t dest_size,
-                         bool ignore_spaces) const {
-  if (MDBX_UNLIKELY(length() % 4 && !ignore_spaces))
-    throw std::domain_error("mdbx::from_base64:: odd length of base64 string");
-  if (MDBX_UNLIKELY(from_base64_bytes() > dest_size))
-    throw_too_small_target_buffer();
-
-  auto src = byte_ptr();
-  for (auto left = length(); left > 0;) {
-    if (MDBX_UNLIKELY(*src <= ' ') &&
-        MDBX_LIKELY(ignore_spaces && isspace(*src))) {
-      ++src;
-      --left;
-      continue;
-    }
-
-    if (MDBX_UNLIKELY(left < 3)) {
-    bailout:
-      throw std::domain_error("mdbx::from_base64:: invalid base64 string");
-    }
-    const signed char a = b64_map[src[0]], b = b64_map[src[1]],
-                      c = b64_map[src[2]], d = b64_map[src[3]];
-    if (MDBX_UNLIKELY(b64_4to3(a, b, c, d, dest) < 0)) {
-      if (left == 4 && (a | b) >= 0 && d == EQ) {
-        if (c >= 0)
-          return dest + 2;
-        if (c == d)
-          return dest + 1;
-      }
-      goto bailout;
-    }
-    src += 4;
-    left -= 4;
-  }
-  return dest;
-}
-
-bool slice::is_base64(bool ignore_spaces) const noexcept {
-  if (MDBX_UNLIKELY(length() % 4 && !ignore_spaces))
-    return false;
-
-  bool got = false;
-  auto src = byte_ptr();
-  for (auto left = length(); left > 0;) {
-    if (MDBX_UNLIKELY(*src <= ' ') &&
-        MDBX_LIKELY(ignore_spaces && isspace(*src))) {
-      ++src;
-      --left;
-      continue;
-    }
-
-    if (MDBX_UNLIKELY(left < 3))
-      return false;
-    const signed char a = b64_map[src[0]], b = b64_map[src[1]],
-                      c = b64_map[src[2]], d = b64_map[src[3]];
-    if (MDBX_UNLIKELY((a | b | c | d) < 0)) {
-      if (left == 4 && (a | b) >= 0 && d == EQ && (c >= 0 || c == d))
-        return true;
-      return false;
-    }
-    got = true;
-    src += 4;
-    left -= 4;
-  }
-  return got;
-}
-
-//------------------------------------------------------------------------------
-
-template class LIBMDBX_API_TYPE buffer<legacy_allocator>;
-
-#if defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
-template class LIBMDBX_API_TYPE buffer<polymorphic_allocator>;
-#endif /* __cpp_lib_memory_resource >= 201603L */
-
-//------------------------------------------------------------------------------
-
-static inline MDBX_env_flags_t mode2flags(env::mode mode) {
-  switch (mode) {
-  default:
-    MDBX_CXX20_UNLIKELY throw std::invalid_argument("db::mode is invalid");
-  case env::mode::readonly:
-    return MDBX_RDONLY;
-  case env::mode::write_file_io:
-    return MDBX_ENV_DEFAULTS;
-  case env::mode::write_mapped_io:
-    return MDBX_WRITEMAP;
-  }
-}
-
-__cold MDBX_env_flags_t
-env::operate_parameters::make_flags(bool accede, bool use_subdirectory) const {
-  MDBX_env_flags_t flags = mode2flags(mode);
-  if (accede)
-    flags |= MDBX_ACCEDE;
-  if (!use_subdirectory)
-    flags |= MDBX_NOSUBDIR;
-  if (options.exclusive)
-    flags |= MDBX_EXCLUSIVE;
-  if (options.orphan_read_transactions)
-    flags |= MDBX_NOTLS;
-  if (options.disable_readahead)
-    flags |= MDBX_NORDAHEAD;
-  if (options.disable_clear_memory)
-    flags |= MDBX_NOMEMINIT;
-
-  if (mode != readonly) {
-    if (options.nested_write_transactions)
-      flags &= ~MDBX_WRITEMAP;
-    if (reclaiming.coalesce)
-      flags |= MDBX_COALESCE;
-    if (reclaiming.lifo)
-      flags |= MDBX_LIFORECLAIM;
-    switch (durability) {
-    default:
-      MDBX_CXX20_UNLIKELY throw std::invalid_argument(
-          "db::durability is invalid");
-    case env::durability::robust_synchronous:
-      break;
-    case env::durability::half_synchronous_weak_last:
-      flags |= MDBX_NOMETASYNC;
-      break;
-    case env::durability::lazy_weak_tail:
-      static_assert(MDBX_MAPASYNC == MDBX_SAFE_NOSYNC, "WTF? Obsolete C API?");
-      flags |= MDBX_SAFE_NOSYNC;
-      break;
-    case env::durability::whole_fragile:
-      flags |= MDBX_UTTERLY_NOSYNC;
-      break;
-    }
-  }
-  return flags;
-}
-
-env::mode
-env::operate_parameters::mode_from_flags(MDBX_env_flags_t flags) noexcept {
-  if (flags & MDBX_RDONLY)
-    return env::mode::readonly;
-  return (flags & MDBX_WRITEMAP) ? env::mode::write_mapped_io
-                                 : env::mode::write_file_io;
-}
-
-env::durability env::operate_parameters::durability_from_flags(
-    MDBX_env_flags_t flags) noexcept {
-  if ((flags & MDBX_UTTERLY_NOSYNC) == MDBX_UTTERLY_NOSYNC)
-    return env::durability::whole_fragile;
-  if (flags & MDBX_SAFE_NOSYNC)
-    return env::durability::lazy_weak_tail;
-  if (flags & MDBX_NOMETASYNC)
-    return env::durability::half_synchronous_weak_last;
-  return env::durability::robust_synchronous;
-}
-
-env::reclaiming_options::reclaiming_options(MDBX_env_flags_t flags) noexcept
-    : lifo((flags & MDBX_LIFORECLAIM) ? true : false),
-      coalesce((flags & MDBX_COALESCE) ? true : false) {}
-
-env::operate_options::operate_options(MDBX_env_flags_t flags) noexcept
-    : orphan_read_transactions(
-          ((flags & (MDBX_NOTLS | MDBX_EXCLUSIVE)) == MDBX_NOTLS) ? true
-                                                                  : false),
-      nested_write_transactions((flags & (MDBX_WRITEMAP | MDBX_RDONLY)) ? false
-                                                                        : true),
-      exclusive((flags & MDBX_EXCLUSIVE) ? true : false),
-      disable_readahead((flags & MDBX_NORDAHEAD) ? true : false),
-      disable_clear_memory((flags & MDBX_NOMEMINIT) ? true : false) {}
-
-env::operate_parameters::operate_parameters(const env &env)
-    : max_maps(env.max_maps()), max_readers(env.max_readers()) {
-  const auto flags = env.get_flags();
-  mode = mode_from_flags(flags);
-  durability = durability_from_flags(flags);
-  reclaiming = reclaiming_from_flags(flags);
-  options = options_from_flags(flags);
-}
-
-bool env::is_pristine() const {
-  return get_stat().ms_mod_txnid == 0 &&
-         get_info().mi_recent_txnid == INITIAL_TXNID;
-}
-
-bool env::is_empty() const { return get_stat().ms_branch_pages == 0; }
-
-#ifdef MDBX_STD_FILESYSTEM_PATH
-env &env::copy(const ::std::filesystem::path &destination, bool compactify,
-               bool force_dynamic_size) {
-  const path_to_pchar<::std::filesystem::path> utf8(destination);
-  error::success_or_throw(
-      ::mdbx_env_copy(handle_, utf8,
-                      (compactify ? MDBX_CP_COMPACT : MDBX_CP_DEFAULTS) |
-                          (force_dynamic_size ? MDBX_CP_FORCE_DYNAMIC_SIZE
-                                              : MDBX_CP_DEFAULTS)));
-  return *this;
-}
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-
-#if defined(_WIN32) || defined(_WIN64)
-env &env::copy(const ::std::wstring &destination, bool compactify,
-               bool force_dynamic_size) {
-  const path_to_pchar<::std::wstring> utf8(destination);
-  error::success_or_throw(
-      ::mdbx_env_copy(handle_, utf8,
-                      (compactify ? MDBX_CP_COMPACT : MDBX_CP_DEFAULTS) |
-                          (force_dynamic_size ? MDBX_CP_FORCE_DYNAMIC_SIZE
-                                              : MDBX_CP_DEFAULTS)));
-  return *this;
-}
-#endif /* Windows */
-
-env &env::copy(const ::std::string &destination, bool compactify,
-               bool force_dynamic_size) {
-  const path_to_pchar<::std::string> utf8(destination);
-  error::success_or_throw(
-      ::mdbx_env_copy(handle_, utf8,
-                      (compactify ? MDBX_CP_COMPACT : MDBX_CP_DEFAULTS) |
-                          (force_dynamic_size ? MDBX_CP_FORCE_DYNAMIC_SIZE
-                                              : MDBX_CP_DEFAULTS)));
-  return *this;
-}
-
-env &env::copy(filehandle fd, bool compactify, bool force_dynamic_size) {
-  error::success_or_throw(
-      ::mdbx_env_copy2fd(handle_, fd,
-                         (compactify ? MDBX_CP_COMPACT : MDBX_CP_DEFAULTS) |
-                             (force_dynamic_size ? MDBX_CP_FORCE_DYNAMIC_SIZE
-                                                 : MDBX_CP_DEFAULTS)));
-  return *this;
-}
-
-path env::get_path() const {
-  const char *c_str;
-  error::success_or_throw(::mdbx_env_get_path(handle_, &c_str));
-  return pchar_to_path<path>(c_str);
-}
-
-#ifdef MDBX_STD_FILESYSTEM_PATH
-bool env::remove(const ::std::filesystem::path &pathname,
-                 const remove_mode mode) {
-  const path_to_pchar<::std::filesystem::path> utf8(pathname);
-  return error::boolean_or_throw(
-      ::mdbx_env_delete(utf8, MDBX_env_delete_mode_t(mode)));
-}
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-
-#if defined(_WIN32) || defined(_WIN64)
-bool env::remove(const ::std::wstring &pathname, const remove_mode mode) {
-  const path_to_pchar<::std::wstring> utf8(pathname);
-  return error::boolean_or_throw(
-      ::mdbx_env_delete(utf8, MDBX_env_delete_mode_t(mode)));
-}
-#endif /* Windows */
-
-bool env::remove(const ::std::string &pathname, const remove_mode mode) {
-  const path_to_pchar<::std::string> utf8(pathname);
-  return error::boolean_or_throw(
-      ::mdbx_env_delete(utf8, MDBX_env_delete_mode_t(mode)));
-}
-
-//------------------------------------------------------------------------------
-
-static inline MDBX_env *create_env() {
-  MDBX_env *ptr;
-  error::success_or_throw(::mdbx_env_create(&ptr));
-  assert(ptr != nullptr);
-  return ptr;
-}
-
-env_managed::~env_managed() noexcept {
-  if (handle_)
-    error::success_or_panic(::mdbx_env_close(handle_), "mdbx::~env()",
-                            "mdbx_env_close");
-}
-
-void env_managed::close(bool dont_sync) {
-  const error rc =
-      static_cast<MDBX_error_t>(::mdbx_env_close_ex(handle_, dont_sync));
-  switch (rc.code()) {
-  case MDBX_EBADSIGN:
-    handle_ = nullptr;
-    __fallthrough /* fall through */;
-  default:
-    rc.throw_exception();
-  case MDBX_SUCCESS:
-    handle_ = nullptr;
-  }
-}
-
-__cold void env_managed::setup(unsigned max_maps, unsigned max_readers) {
-  if (max_readers > 0)
-    error::success_or_throw(::mdbx_env_set_maxreaders(handle_, max_readers));
-  if (max_maps > 0)
-    error::success_or_throw(::mdbx_env_set_maxdbs(handle_, max_maps));
-}
-
-#ifdef MDBX_STD_FILESYSTEM_PATH
-__cold env_managed::env_managed(const ::std::filesystem::path &pathname,
-                                const operate_parameters &op, bool accede)
-    : env_managed(create_env()) {
-  setup(op.max_maps, op.max_readers);
-  const path_to_pchar<::std::filesystem::path> utf8(pathname);
-  error::success_or_throw(
-      ::mdbx_env_open(handle_, utf8, op.make_flags(accede), 0));
-
-  if (op.options.nested_write_transactions &&
-      !get_options().nested_write_transactions)
-    error::throw_exception(MDBX_INCOMPATIBLE);
-}
-
-__cold env_managed::env_managed(const ::std::filesystem::path &pathname,
-                                const env_managed::create_parameters &cp,
-                                const env::operate_parameters &op, bool accede)
-    : env_managed(create_env()) {
-  setup(op.max_maps, op.max_readers);
-  const path_to_pchar<::std::filesystem::path> utf8(pathname);
-  set_geometry(cp.geometry);
-  error::success_or_throw(
-      ::mdbx_env_open(handle_, utf8, op.make_flags(accede, cp.use_subdirectory),
-                      cp.file_mode_bits));
-
-  if (op.options.nested_write_transactions &&
-      !get_options().nested_write_transactions)
-    error::throw_exception(MDBX_INCOMPATIBLE);
-}
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-
-#if defined(_WIN32) || defined(_WIN64)
-__cold env_managed::env_managed(const ::std::wstring &pathname,
-                                const operate_parameters &op, bool accede)
-    : env_managed(create_env()) {
-  setup(op.max_maps, op.max_readers);
-  const path_to_pchar<::std::wstring> utf8(pathname);
-  error::success_or_throw(
-      ::mdbx_env_open(handle_, utf8, op.make_flags(accede), 0));
-
-  if (op.options.nested_write_transactions &&
-      !get_options().nested_write_transactions)
-    error::throw_exception(MDBX_INCOMPATIBLE);
-}
-
-__cold env_managed::env_managed(const ::std::wstring &pathname,
-                                const env_managed::create_parameters &cp,
-                                const env::operate_parameters &op, bool accede)
-    : env_managed(create_env()) {
-  setup(op.max_maps, op.max_readers);
-  const path_to_pchar<::std::wstring> utf8(pathname);
-  set_geometry(cp.geometry);
-  error::success_or_throw(
-      ::mdbx_env_open(handle_, utf8, op.make_flags(accede, cp.use_subdirectory),
-                      cp.file_mode_bits));
-
-  if (op.options.nested_write_transactions &&
-      !get_options().nested_write_transactions)
-    error::throw_exception(MDBX_INCOMPATIBLE);
-}
-#endif /* Windows */
-
-__cold env_managed::env_managed(const ::std::string &pathname,
-                                const operate_parameters &op, bool accede)
-    : env_managed(create_env()) {
-  setup(op.max_maps, op.max_readers);
-  const path_to_pchar<::std::string> utf8(pathname);
-  error::success_or_throw(
-      ::mdbx_env_open(handle_, utf8, op.make_flags(accede), 0));
-
-  if (op.options.nested_write_transactions &&
-      !get_options().nested_write_transactions)
-    error::throw_exception(MDBX_INCOMPATIBLE);
-}
-
-__cold env_managed::env_managed(const ::std::string &pathname,
-                                const env_managed::create_parameters &cp,
-                                const env::operate_parameters &op, bool accede)
-    : env_managed(create_env()) {
-  setup(op.max_maps, op.max_readers);
-  const path_to_pchar<::std::string> utf8(pathname);
-  set_geometry(cp.geometry);
-  error::success_or_throw(
-      ::mdbx_env_open(handle_, utf8, op.make_flags(accede, cp.use_subdirectory),
-                      cp.file_mode_bits));
-
-  if (op.options.nested_write_transactions &&
-      !get_options().nested_write_transactions)
-    error::throw_exception(MDBX_INCOMPATIBLE);
-}
-
-//------------------------------------------------------------------------------
-
-txn_managed txn::start_nested() {
-  MDBX_txn *nested;
-  error::throw_on_nullptr(handle_, MDBX_BAD_TXN);
-  error::success_or_throw(::mdbx_txn_begin(mdbx_txn_env(handle_), handle_,
-                                           MDBX_TXN_READWRITE, &nested));
-  assert(nested != nullptr);
-  return txn_managed(nested);
-}
-
-txn_managed::~txn_managed() noexcept {
-  if (handle_)
-    error::success_or_panic(::mdbx_txn_abort(handle_), "mdbx::~txn",
-                            "mdbx_txn_abort");
-}
-
-void txn_managed::abort() {
-  const error err = static_cast<MDBX_error_t>(::mdbx_txn_abort(handle_));
-  if (MDBX_LIKELY(err.code() != MDBX_THREAD_MISMATCH))
-    handle_ = nullptr;
-  if (MDBX_UNLIKELY(err.code() != MDBX_SUCCESS))
-    err.throw_exception();
-}
-
-void txn_managed::commit() {
-  const error err = static_cast<MDBX_error_t>(::mdbx_txn_commit(handle_));
-  if (MDBX_LIKELY(err.code() != MDBX_THREAD_MISMATCH))
-    handle_ = nullptr;
-  if (MDBX_UNLIKELY(err.code() != MDBX_SUCCESS))
-    err.throw_exception();
-}
-
-//------------------------------------------------------------------------------
-
-bool txn::drop_map(const char *name, bool throw_if_absent) {
-  map_handle map;
-  const int err = ::mdbx_dbi_open(handle_, name, MDBX_DB_ACCEDE, &map.dbi);
-  switch (err) {
-  case MDBX_SUCCESS:
-    drop_map(map);
-    return true;
-  case MDBX_NOTFOUND:
-  case MDBX_BAD_DBI:
-    if (!throw_if_absent)
-      return false;
-    MDBX_CXX17_FALLTHROUGH /* fallthrough */;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-bool txn::clear_map(const char *name, bool throw_if_absent) {
-  map_handle map;
-  const int err = ::mdbx_dbi_open(handle_, name, MDBX_DB_ACCEDE, &map.dbi);
-  switch (err) {
-  case MDBX_SUCCESS:
-    clear_map(map);
-    return true;
-  case MDBX_NOTFOUND:
-  case MDBX_BAD_DBI:
-    if (!throw_if_absent)
-      return false;
-    MDBX_CXX17_FALLTHROUGH /* fallthrough */;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-//------------------------------------------------------------------------------
-
-void cursor_managed::close() {
-  if (MDBX_UNLIKELY(!handle_))
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  ::mdbx_cursor_close(handle_);
-  handle_ = nullptr;
-}
-
-//------------------------------------------------------------------------------
-
-__cold ::std::ostream &operator<<(::std::ostream &out, const slice &it) {
-  out << "{";
-  if (!it.is_valid())
-    out << "INVALID." << it.length();
-  else if (it.is_null())
-    out << "NULL";
-  else if (it.empty())
-    out << "EMPTY->" << it.data();
-  else {
-    const slice root(it.head(std::min(it.length(), size_t(64))));
-    out << it.length() << ".";
-    if (root.is_printable())
-      (out << "\"").write(root.char_ptr(), root.length()) << "\"";
-    else
-      out << root.base58_encode();
-    if (root.length() < it.length())
-      out << "...";
-  }
-  return out << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out, const pair &it) {
-  return out << "{" << it.key << " => " << it.value << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out, const pair_result &it) {
-  return out << "{" << (it.done ? "done: " : "non-done: ") << it.key << " => "
-             << it.value << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const ::mdbx::env::geometry::size &it) {
-  switch (it.bytes) {
-  case ::mdbx::env::geometry::default_value:
-    return out << "default";
-  case ::mdbx::env::geometry::minimal_value:
-    return out << "minimal";
-  case ::mdbx::env::geometry::maximal_value:
-    return out << "maximal";
-  }
-
-  const auto bytes = (it.bytes < 0) ? out << "-",
-             size_t(-it.bytes) : size_t(it.bytes);
-  struct {
-    size_t one;
-    const char *suffix;
-  } static const scales[] = {
-#if MDBX_WORDBITS > 32
-    {env_managed::geometry::EiB, "EiB"},
-    {env_managed::geometry::EB, "EB"},
-    {env_managed::geometry::PiB, "PiB"},
-    {env_managed::geometry::PB, "PB"},
-    {env_managed::geometry::TiB, "TiB"},
-    {env_managed::geometry::TB, "TB"},
-#endif
-    {env_managed::geometry::GiB, "GiB"},
-    {env_managed::geometry::GB, "GB"},
-    {env_managed::geometry::MiB, "MiB"},
-    {env_managed::geometry::MB, "MB"},
-    {env_managed::geometry::KiB, "KiB"},
-    {env_managed::geometry::kB, "kB"},
-    {1, " bytes"}
-  };
-
-  for (const auto i : scales)
-    if (bytes % i.one == 0)
-      return out << bytes / i.one << i.suffix;
-
-  assert(false);
-  __unreachable();
-  return out;
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const env::geometry &it) {
-  return                                                                //
-      out << "\tlower " << env::geometry::size(it.size_lower)           //
-          << ",\n\tnow " << env::geometry::size(it.size_now)            //
-          << ",\n\tupper " << env::geometry::size(it.size_upper)        //
-          << ",\n\tgrowth " << env::geometry::size(it.growth_step)      //
-          << ",\n\tshrink " << env::geometry::size(it.shrink_threshold) //
-          << ",\n\tpagesize " << env::geometry::size(it.pagesize) << "\n";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const env::operate_parameters &it) {
-  return out << "{\n"                                 //
-             << "\tmax_maps " << it.max_maps          //
-             << ",\n\tmax_readers " << it.max_readers //
-             << ",\n\tmode " << it.mode               //
-             << ",\n\tdurability " << it.durability   //
-             << ",\n\treclaiming " << it.reclaiming   //
-             << ",\n\toptions " << it.options         //
-             << "\n}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out, const env::mode &it) {
-  switch (it) {
-  case env::mode::readonly:
-    return out << "readonly";
-  case env::mode::write_file_io:
-    return out << "write_file_io";
-  case env::mode::write_mapped_io:
-    return out << "write_mapped_io";
-  default:
-    return out << "mdbx::env::mode::invalid";
-  }
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const env::durability &it) {
-  switch (it) {
-  case env::durability::robust_synchronous:
-    return out << "robust_synchronous";
-  case env::durability::half_synchronous_weak_last:
-    return out << "half_synchronous_weak_last";
-  case env::durability::lazy_weak_tail:
-    return out << "lazy_weak_tail";
-  case env::durability::whole_fragile:
-    return out << "whole_fragile";
-  default:
-    return out << "mdbx::env::durability::invalid";
-  }
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const env::reclaiming_options &it) {
-  return out << "{"                                            //
-             << "lifo: " << (it.lifo ? "yes" : "no")           //
-             << ", coalesce: " << (it.coalesce ? "yes" : "no") //
-             << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const env::operate_options &it) {
-  static const char comma[] = ", ";
-  const char *delimiter = "";
-  out << "{";
-  if (it.orphan_read_transactions) {
-    out << delimiter << "orphan_read_transactions";
-    delimiter = comma;
-  }
-  if (it.nested_write_transactions) {
-    out << delimiter << "nested_write_transactions";
-    delimiter = comma;
-  }
-  if (it.exclusive) {
-    out << delimiter << "exclusive";
-    delimiter = comma;
-  }
-  if (it.disable_readahead) {
-    out << delimiter << "disable_readahead";
-    delimiter = comma;
-  }
-  if (it.disable_clear_memory) {
-    out << delimiter << "disable_clear_memory";
-    delimiter = comma;
-  }
-  if (delimiter != comma)
-    out << "default";
-  return out << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const env_managed::create_parameters &it) {
-  return out << "{\n"                                                        //
-             << "\tfile_mode " << std::oct << it.file_mode_bits << std::dec  //
-             << ",\n\tsubdirectory " << (it.use_subdirectory ? "yes" : "no") //
-             << ",\n"
-             << it.geometry << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const MDBX_log_level_t &it) {
-  switch (it) {
-  case MDBX_LOG_FATAL:
-    return out << "LOG_FATAL";
-  case MDBX_LOG_ERROR:
-    return out << "LOG_ERROR";
-  case MDBX_LOG_WARN:
-    return out << "LOG_WARN";
-  case MDBX_LOG_NOTICE:
-    return out << "LOG_NOTICE";
-  case MDBX_LOG_VERBOSE:
-    return out << "LOG_VERBOSE";
-  case MDBX_LOG_DEBUG:
-    return out << "LOG_DEBUG";
-  case MDBX_LOG_TRACE:
-    return out << "LOG_TRACE";
-  case MDBX_LOG_EXTRA:
-    return out << "LOG_EXTRA";
-  case MDBX_LOG_DONTCHANGE:
-    return out << "LOG_DONTCHANGE";
-  default:
-    return out << "mdbx::log_level::invalid";
-  }
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const MDBX_debug_flags_t &it) {
-  if (it == MDBX_DBG_DONTCHANGE)
-    return out << "DBG_DONTCHANGE";
-
-  static const char comma[] = "|";
-  const char *delimiter = "";
-  out << "{";
-  if (it & MDBX_DBG_ASSERT) {
-    out << delimiter << "DBG_ASSERT";
-    delimiter = comma;
-  }
-  if (it & MDBX_DBG_AUDIT) {
-    out << delimiter << "DBG_AUDIT";
-    delimiter = comma;
-  }
-  if (it & MDBX_DBG_JITTER) {
-    out << delimiter << "DBG_JITTER";
-    delimiter = comma;
-  }
-  if (it & MDBX_DBG_DUMP) {
-    out << delimiter << "DBG_DUMP";
-    delimiter = comma;
-  }
-  if (it & MDBX_DBG_LEGACY_MULTIOPEN) {
-    out << delimiter << "DBG_LEGACY_MULTIOPEN";
-    delimiter = comma;
-  }
-  if (it & MDBX_DBG_LEGACY_OVERLAP) {
-    out << delimiter << "DBG_LEGACY_OVERLAP";
-    delimiter = comma;
-  }
-  if (delimiter != comma)
-    out << "DBG_NONE";
-  return out << "}";
-}
-
-__cold ::std::ostream &operator<<(::std::ostream &out,
-                                  const ::mdbx::error &err) {
-  return out << err.what() << " (" << long(err.code()) << ")";
-}
-
-} // namespace mdbx
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx.h b/plugins/Dbx_mdbx/src/libmdbx/mdbx.h
deleted file mode 100644
index 9d7dba99e9..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx.h
+++ /dev/null
@@ -1,5017 +0,0 @@
-/**
-
-_libmdbx_ is an extremely fast, compact, powerful, embedded,
-transactional [key-value
-store](https://en.wikipedia.org/wiki/Key-value_database) database, with
-[permissive license](./LICENSE). _MDBX_ has a specific set of properties and
-capabilities, focused on creating unique lightweight solutions with
-extraordinary performance.
-
-_libmdbx_ is superior to [LMDB](https://bit.ly/26ts7tL) in terms of features
-and reliability, not inferior in performance. In comparison to LMDB, _libmdbx_
-makes many things just work perfectly, not silently and catastrophically
-break down. _libmdbx_ supports Linux, Windows, MacOS, OSX, iOS, Android,
-FreeBSD, DragonFly, Solaris, OpenSolaris, OpenIndiana, NetBSD, OpenBSD and other
-systems compliant with POSIX.1-2008.
-
-_The Future will (be) [Positive](https://www.ptsecurity.com). Всё будет хорошо._
-
-
-\section copyright LICENSE & COPYRIGHT
-
-\authors Copyright (c) 2015-2021, Leonid Yuriev <leo@yuriev.ru>
-and other _libmdbx_ authors: please see [AUTHORS](./AUTHORS) file.
-
-\copyright Redistribution and use in source and binary forms, with or without
-modification, are permitted only as authorized by the OpenLDAP Public License.
-
-A copy of this license is available in the file LICENSE in the
-top-level directory of the distribution or, alternatively, at
-<http://www.OpenLDAP.org/license.html>.
-
- ---
-
-This code is derived from "LMDB engine" written by
-Howard Chu (Symas Corporation), which itself derived from btree.c
-written by Martin Hedenfalk.
-
- ---
-
-Portions Copyright 2011-2015 Howard Chu, Symas Corp. All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted only as authorized by the OpenLDAP
-Public License.
-
-A copy of this license is available in the file LICENSE in the
-top-level directory of the distribution or, alternatively, at
-<http://www.OpenLDAP.org/license.html>.
-
- ---
-
-Portions Copyright (c) 2009, 2010 Martin Hedenfalk <martin@bzero.se>
-
-Permission to use, copy, modify, and distribute this software for any
-purpose with or without fee is hereby granted, provided that the above
-copyright notice and this permission notice appear in all copies.
-
-THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
-MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
-ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-
-*******************************************************************************/
-
-#pragma once
-#ifndef LIBMDBX_H
-#define LIBMDBX_H
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/**
- \file mdbx.h
- \brief The libmdbx C API header file
-
- \defgroup c_api C API
- @{
- \defgroup c_err Error handling
- \defgroup c_opening Opening & Closing
- \defgroup c_transactions Transactions
- \defgroup c_dbi Databases
- \defgroup c_crud Create/Read/Update/Delete (see Quick Reference in details)
-
- \details
- \anchor c_crud_hints
-# Quick Reference for Insert/Update/Delete operations
-
-Historically, libmdbx inherits the API basis from LMDB, where it is often
-difficult to select flags/options and functions for the desired operation.
-So it is recommend using this hints.
-
-## Databases with UNIQUE keys
-
-In databases created without the \ref MDBX_DUPSORT option, keys are always
-unique. Thus always a single value corresponds to the each key, and so there
-are only a few cases of changing data.
-
-| Case                                        | Flags to use        | Result                 |
-|---------------------------------------------|---------------------|------------------------|
-| _INSERTING_|||
-|Key is absent → Insertion                    |\ref MDBX_NOOVERWRITE|Insertion               |
-|Key exist → Error since key present          |\ref MDBX_NOOVERWRITE|Error \ref MDBX_KEYEXIST and return Present value|
-| _UPSERTING_|||
-|Key is absent → Insertion                    |\ref MDBX_UPSERT     |Insertion               |
-|Key exist → Update                           |\ref MDBX_UPSERT     |Update                  |
-|  _UPDATING_|||
-|Key is absent → Error since no such key      |\ref MDBX_CURRENT    |Error \ref MDBX_NOTFOUND|
-|Key exist → Update                           |\ref MDBX_CURRENT    |Update value            |
-| _DELETING_|||
-|Key is absent → Error since no such key      |\ref mdbx_del() or \ref mdbx_replace()|Error \ref MDBX_NOTFOUND|
-|Key exist → Delete by key                    |\ref mdbx_del() with the parameter `data = NULL`|Deletion|
-|Key exist → Delete by key with with data matching check|\ref mdbx_del() with the parameter `data` filled with the value which should be match for deletion|Deletion or \ref MDBX_NOTFOUND if the value does not match|
-|Delete at the current cursor position        |\ref mdbx_cursor_del() with \ref MDBX_CURRENT flag|Deletion|
-|Extract (read & delete) value by the key     |\ref mdbx_replace() with zero flag and parameter `new_data = NULL`|Returning a deleted value|
-
-
-## Databases with NON-UNIQUE keys
-
-In databases created with the \ref MDBX_DUPSORT (Sorted Duplicates) option, keys
-may be non unique. Such non-unique keys in a key-value database may be treated
-as a duplicates or as like a multiple values corresponds to keys.
-
-
-| Case                                        | Flags to use        | Result                 |
-|---------------------------------------------|---------------------|------------------------|
-| _INSERTING_|||
-|Key is absent → Insertion                    |\ref MDBX_NOOVERWRITE|Insertion|
-|Key exist → Needn't to add new values        |\ref MDBX_NOOVERWRITE|Error \ref MDBX_KEYEXIST with returning the first value from those already present|
-| _UPSERTING_|||
-|Key is absent → Insertion                    |\ref MDBX_UPSERT     |Insertion|
-|Key exist → Wanna to add new values          |\ref MDBX_UPSERT     |Add one more value to the key|
-|Key exist → Replace all values with a new one|\ref MDBX_UPSERT + \ref MDBX_ALLDUPS|Overwrite by single new value|
-|  _UPDATING_|||
-|Key is absent → Error since no such key      |\ref MDBX_CURRENT    |Error \ref MDBX_NOTFOUND|
-|Key exist, Single value → Update             |\ref MDBX_CURRENT    |Update single value    |
-|Key exist, Multiple values → Replace all values with a new one|\ref MDBX_CURRENT + \ref MDBX_ALLDUPS|Overwrite by single new value|
-|Key exist, Multiple values → Error since it is unclear which of the values should be updated|\ref mdbx_put() with \ref MDBX_CURRENT|Error \ref MDBX_EMULTIVAL|
-|Key exist, Multiple values → Update particular entry of multi-value|\ref mdbx_replace() with \ref MDBX_CURRENT + \ref MDBX_NOOVERWRITE and the parameter `old_value` filled with the value that wanna to update|Update one multi-value entry|
-|Key exist, Multiple values → Update the current entry of multi-value|\ref mdbx_cursor_put() with \ref MDBX_CURRENT|Update one multi-value entry|
-| _DELETING_|||
-|Key is absent → Error since no such key      |\ref mdbx_del() or \ref mdbx_replace()|Error \ref MDBX_NOTFOUND|
-|Key exist → Delete all values corresponds given key|\ref mdbx_del() with the parameter `data = NULL`|Deletion|
-|Key exist → Delete particular value corresponds given key|\ref mdbx_del() with the parameter `data` filled with the value that wanna to delete, or \ref mdbx_replace() with \ref MDBX_CURRENT + \ref MDBX_NOOVERWRITE and the `old_value` parameter filled with the value that wanna to delete and `new_data = NULL`| Deletion or \ref MDBX_NOTFOUND if no such key-value pair|
-|Delete one value at the current cursor position|\ref mdbx_cursor_del() with \ref MDBX_CURRENT flag|Deletion only the current entry|
-|Delete all values of key at the current cursor position|\ref mdbx_cursor_del() with with \ref MDBX_ALLDUPS flag|Deletion all duplicates of key (all multi-values) at the current cursor position|
-
- \defgroup c_cursors Cursors
- \defgroup c_statinfo Statistics & Information
- \defgroup c_settings Settings
- \defgroup c_debug Logging and runtime debug
- \defgroup c_rqest Range query estimation
- \defgroup c_extra Extra operations
-*/
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#include <stdarg.h>
-#include <stddef.h>
-#include <stdint.h>
-
-#if defined(_WIN32) || defined(_WIN64)
-#include <windows.h>
-#include <winnt.h>
-#ifndef __mode_t_defined
-typedef unsigned short mdbx_mode_t;
-#else
-typedef mode_t mdbx_mode_t;
-#endif /* __mode_t_defined */
-typedef HANDLE mdbx_filehandle_t;
-typedef DWORD mdbx_pid_t;
-typedef DWORD mdbx_tid_t;
-#else                  /* Windows */
-#include <errno.h>     /* for error codes */
-#include <pthread.h>   /* for pthread_t */
-#include <sys/types.h> /* for pid_t */
-#include <sys/uio.h>   /* for struct iovec */
-#define HAVE_STRUCT_IOVEC 1
-typedef int mdbx_filehandle_t;
-typedef pid_t mdbx_pid_t;
-typedef pthread_t mdbx_tid_t;
-typedef mode_t mdbx_mode_t;
-#endif /* !Windows */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-/** @} close c_api
- * \defgroup api_macros Common Macros
- * @{ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __has_attribute
-#define __has_attribute(x) (0)
-#endif /* __has_attribute */
-
-#ifndef __has_cpp_attribute
-#define __has_cpp_attribute(x) 0
-#endif /* __has_cpp_attribute */
-
-#ifndef __has_feature
-#define __has_feature(x) (0)
-#endif /* __has_feature */
-
-#ifndef __has_extension
-#define __has_extension(x) (0)
-#endif /* __has_extension */
-
-#ifndef __has_builtin
-#define __has_builtin(x) (0)
-#endif /* __has_builtin */
-
-/** Many functions have no effects except the return value and their
- * return value depends only on the parameters and/or global variables.
- * Such a function can be subject to common subexpression elimination
- * and loop optimization just as an arithmetic operator would be.
- * These functions should be declared with the attribute pure. */
-#if (defined(__GNUC__) || __has_attribute(__pure__)) &&                        \
-    (!defined(__clang__) /* https://bugs.llvm.org/show_bug.cgi?id=43275 */     \
-     || !defined(__cplusplus) || !__has_feature(cxx_exceptions))
-#define MDBX_PURE_FUNCTION __attribute__((__pure__))
-#elif defined(_MSC_VER) && !defined(__clang__) && _MSC_VER >= 1920
-#define MDBX_PURE_FUNCTION
-#elif defined(__cplusplus) && __has_cpp_attribute(gnu::pure) &&                \
-    (!defined(__clang__) || !__has_feature(cxx_exceptions))
-#define MDBX_PURE_FUNCTION [[gnu::pure]]
-#else
-#define MDBX_PURE_FUNCTION
-#endif /* MDBX_PURE_FUNCTION */
-
-/** Like \ref MDBX_PURE_FUNCTION with addition `noexcept` restriction
- * that is compatible to CLANG and proposed [[pure]]. */
-#if defined(__GNUC__) ||                                                       \
-    (__has_attribute(__pure__) && __has_attribute(__nothrow__))
-#define MDBX_NOTHROW_PURE_FUNCTION __attribute__((__pure__, __nothrow__))
-#elif defined(_MSC_VER) && !defined(__clang__) && _MSC_VER >= 1920
-#if __has_cpp_attribute(pure)
-#define MDBX_NOTHROW_PURE_FUNCTION [[pure]]
-#else
-#define MDBX_NOTHROW_PURE_FUNCTION
-#endif
-#elif defined(__cplusplus) && __has_cpp_attribute(gnu::pure)
-#if __has_cpp_attribute(gnu::nothrow)
-#define MDBX_NOTHROW_PURE_FUNCTION [[gnu::pure, gnu::nothrow]]
-#else
-#define MDBX_NOTHROW_PURE_FUNCTION [[gnu::pure]]
-#endif
-#elif defined(__cplusplus) && __has_cpp_attribute(pure)
-#define MDBX_NOTHROW_PURE_FUNCTION [[pure]]
-#else
-#define MDBX_NOTHROW_PURE_FUNCTION
-#endif /* MDBX_NOTHROW_PURE_FUNCTION */
-
-/** Many functions do not examine any values except their arguments,
- * and have no effects except the return value. Basically this is just
- * slightly more strict class than the PURE attribute, since function
- * is not allowed to read global memory.
- *
- * Note that a function that has pointer arguments and examines the
- * data pointed to must not be declared const. Likewise, a function
- * that calls a non-const function usually must not be const.
- * It does not make sense for a const function to return void. */
-#if (defined(__GNUC__) || __has_attribute(__pure__)) &&                        \
-    (!defined(__clang__) /* https://bugs.llvm.org/show_bug.cgi?id=43275 */     \
-     || !defined(__cplusplus) || !__has_feature(cxx_exceptions))
-#define MDBX_CONST_FUNCTION __attribute__((__const__))
-#elif defined(_MSC_VER) && !defined(__clang__) && _MSC_VER >= 1920
-#define MDBX_CONST_FUNCTION MDBX_PURE_FUNCTION
-#elif defined(__cplusplus) && __has_cpp_attribute(gnu::const) &&               \
-    (!defined(__clang__) || !__has_feature(cxx_exceptions))
-#define MDBX_CONST_FUNCTION [[gnu::const]]
-#else
-#define MDBX_CONST_FUNCTION MDBX_PURE_FUNCTION
-#endif /* MDBX_CONST_FUNCTION */
-
-/** Like \ref MDBX_CONST_FUNCTION with addition `noexcept` restriction
- * that is compatible to CLANG and future [[const]]. */
-#if defined(__GNUC__) ||                                                       \
-    (__has_attribute(__const__) && __has_attribute(__nothrow__))
-#define MDBX_NOTHROW_CONST_FUNCTION __attribute__((__const__, __nothrow__))
-#elif defined(_MSC_VER) && !defined(__clang__) && _MSC_VER >= 1920
-#define MDBX_NOTHROW_CONST_FUNCTION MDBX_NOTHROW_PURE_FUNCTION
-#elif defined(__cplusplus) && __has_cpp_attribute(gnu::const)
-#if __has_cpp_attribute(gnu::nothrow)
-#define MDBX_NOTHROW_PURE_FUNCTION [[gnu::const, gnu::nothrow]]
-#else
-#define MDBX_NOTHROW_PURE_FUNCTION [[gnu::const]]
-#endif
-#elif defined(__cplusplus) && __has_cpp_attribute(const)
-#define MDBX_NOTHROW_CONST_FUNCTION [[const]]
-#else
-#define MDBX_NOTHROW_CONST_FUNCTION MDBX_NOTHROW_PURE_FUNCTION
-#endif /* MDBX_NOTHROW_CONST_FUNCTION */
-
-#ifndef MDBX_DEPRECATED /* may be predefined to avoid warnings "deprecated" */
-#ifdef __deprecated
-#define MDBX_DEPRECATED __deprecated
-#elif defined(__GNUC__) || __has_attribute(__deprecated__)
-#define MDBX_DEPRECATED __attribute__((__deprecated__))
-#elif defined(_MSC_VER)
-#define MDBX_DEPRECATED __declspec(deprecated)
-#else
-#define MDBX_DEPRECATED
-#endif
-#endif /* MDBX_DEPRECATED */
-
-#ifndef __dll_export
-#if defined(_WIN32) || defined(__CYGWIN__)
-#if defined(__GNUC__) || __has_attribute(__dllexport__)
-#define __dll_export __attribute__((__dllexport__))
-#elif defined(_MSC_VER)
-#define __dll_export __declspec(dllexport)
-#else
-#define __dll_export
-#endif
-#elif defined(__GNUC__) || __has_attribute(__visibility__)
-#define __dll_export __attribute__((__visibility__("default")))
-#else
-#define __dll_export
-#endif
-#endif /* __dll_export */
-
-#ifndef __dll_import
-#if defined(_WIN32) || defined(__CYGWIN__)
-#if defined(__GNUC__) || __has_attribute(__dllimport__)
-#define __dll_import __attribute__((__dllimport__))
-#elif defined(_MSC_VER)
-#define __dll_import __declspec(dllimport)
-#else
-#define __dll_import
-#endif
-#else
-#define __dll_import
-#endif
-#endif /* __dll_import */
-
-/** \brief Auxiliary macro for robustly define the both inline version of API
- * function and non-inline fallback dll-exported version for applications linked
- * with old version of libmdbx, with a strictly ODR-common implementation. */
-#if !defined(LIBMDBX_INTERNALS)
-#define LIBMDBX_INLINE_API(TYPE, NAME, ARGS) static __inline TYPE NAME ARGS
-#else
-#define LIBMDBX_INLINE_API(TYPE, NAME, ARGS)                                   \
-  /* proto of exported which uses common impl */ LIBMDBX_API TYPE NAME ARGS;   \
-  /* definition of common impl */ static __inline TYPE __inline_##NAME ARGS
-#endif /* LIBMDBX_INLINE_API */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __cplusplus
-#ifndef bool
-#define bool _Bool
-#endif
-#ifndef true
-#define true (1)
-#endif
-#ifndef false
-#define false (0)
-#endif
-#endif /* bool without __cplusplus */
-
-#if !defined(DOXYGEN) && (!defined(__cpp_noexcept_function_type) ||            \
-                          __cpp_noexcept_function_type < 201510L)
-#define MDBX_CXX17_NOEXCEPT
-#else
-#define MDBX_CXX17_NOEXCEPT noexcept
-#endif /* MDBX_CXX17_NOEXCEPT */
-
-/* Workaround for old compilers without properly support for constexpr. */
-#if !defined(__cplusplus)
-#define MDBX_CXX01_CONSTEXPR __inline
-#define MDBX_CXX01_CONSTEXPR_VAR const
-#elif !defined(DOXYGEN) &&                                                     \
-    (!defined(__cpp_constexpr) || __cpp_constexpr < 200704L ||                 \
-     (defined(__LCC__) && __LCC__ < 124) ||                                    \
-     (defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 407) &&          \
-      !defined(__clang__) && !defined(__LCC__)) ||                             \
-     (defined(_MSC_VER) && _MSC_VER < 1910) ||                                 \
-     (defined(__clang__) && __clang_major__ < 4))
-#define MDBX_CXX01_CONSTEXPR inline
-#define MDBX_CXX01_CONSTEXPR_VAR const
-#else
-#define MDBX_CXX01_CONSTEXPR constexpr
-#define MDBX_CXX01_CONSTEXPR_VAR constexpr
-#endif /* MDBX_CXX01_CONSTEXPR */
-
-#if !defined(__cplusplus)
-#define MDBX_CXX11_CONSTEXPR __inline
-#define MDBX_CXX11_CONSTEXPR_VAR const
-#elif !defined(DOXYGEN) &&                                                     \
-    (!defined(__cpp_constexpr) || __cpp_constexpr < 201304 ||                  \
-     (defined(__LCC__) && __LCC__ < 124) ||                                    \
-     (defined(__GNUC__) && __GNUC__ < 6 && !defined(__clang__) &&              \
-      !defined(__LCC__)) ||                                                    \
-     (defined(_MSC_VER) && _MSC_VER < 1910) ||                                 \
-     (defined(__clang__) && __clang_major__ < 5))
-#define MDBX_CXX11_CONSTEXPR inline
-#define MDBX_CXX11_CONSTEXPR_VAR const
-#else
-#define MDBX_CXX11_CONSTEXPR constexpr
-#define MDBX_CXX11_CONSTEXPR_VAR constexpr
-#endif /* MDBX_CXX11_CONSTEXPR */
-
-#if !defined(__cplusplus)
-#define MDBX_CXX14_CONSTEXPR __inline
-#define MDBX_CXX14_CONSTEXPR_VAR const
-#elif defined(DOXYGEN) ||                                                      \
-    defined(__cpp_constexpr) && __cpp_constexpr >= 201304L &&                  \
-        ((defined(_MSC_VER) && _MSC_VER >= 1910) ||                            \
-         (defined(__clang__) && __clang_major__ > 4) ||                        \
-         (defined(__GNUC__) && __GNUC__ > 6) ||                                \
-         (!defined(__GNUC__) && !defined(__clang__) && !defined(_MSC_VER)))
-#define MDBX_CXX14_CONSTEXPR constexpr
-#define MDBX_CXX14_CONSTEXPR_VAR constexpr
-#else
-#define MDBX_CXX14_CONSTEXPR inline
-#define MDBX_CXX14_CONSTEXPR_VAR const
-#endif /* MDBX_CXX14_CONSTEXPR */
-
-#if defined(__noreturn)
-#define MDBX_NORETURN __noreturn
-#elif defined(_Noreturn)
-#define MDBX_NORETURN _Noreturn
-#elif defined(__GNUC__) || __has_attribute(__noreturn__)
-#define MDBX_NORETURN __attribute__((__noreturn__))
-#elif defined(_MSC_VER) && !defined(__clang__)
-#define MDBX_NORETURN __declspec(noreturn)
-#else
-#define MDBX_NORETURN
-#endif /* MDBX_NORETURN */
-
-#ifndef MDBX_PRINTF_ARGS
-#if defined(__GNUC__) || __has_attribute(__format__)
-#define MDBX_PRINTF_ARGS(format_index, first_arg)                              \
-  __attribute__((__format__(__printf__, format_index, first_arg)))
-#else
-#define MDBX_PRINTF_ARGS(format_index, first_arg)
-#endif
-#endif /* MDBX_PRINTF_ARGS */
-
-/* Oh, below are some songs and dances since:
- *  - C++ requires explicit definition of the necessary operators.
- *  - the proper implementation of DEFINE_ENUM_FLAG_OPERATORS for C++ required
- *    the constexpr feature which is broken in most old compilers;
- *  - DEFINE_ENUM_FLAG_OPERATORS may be defined broken as in the Windows SDK. */
-#ifndef DEFINE_ENUM_FLAG_OPERATORS
-
-#ifdef __cplusplus
-#if !defined(__cpp_constexpr) || __cpp_constexpr < 200704L ||                  \
-    (defined(__LCC__) && __LCC__ < 124) ||                                     \
-    (defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 407) &&           \
-     !defined(__clang__) && !defined(__LCC__)) ||                              \
-    (defined(_MSC_VER) && _MSC_VER < 1910) ||                                  \
-    (defined(__clang__) && __clang_major__ < 4)
-/* The constexpr feature is not available or (may be) broken */
-#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 0
-#else
-/* C always allows these operators for enums */
-#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 1
-#endif /* __cpp_constexpr */
-
-/// Define operator overloads to enable bit operations on enum values that are
-/// used to define flags (based on Microsoft's DEFINE_ENUM_FLAG_OPERATORS).
-#define DEFINE_ENUM_FLAG_OPERATORS(ENUM)                                       \
-  extern "C++" {                                                               \
-  MDBX_CXX01_CONSTEXPR ENUM operator|(ENUM a, ENUM b) {                        \
-    return ENUM(unsigned(a) | unsigned(b));                                    \
-  }                                                                            \
-  MDBX_CXX14_CONSTEXPR ENUM &operator|=(ENUM &a, ENUM b) { return a = a | b; } \
-  MDBX_CXX01_CONSTEXPR ENUM operator&(ENUM a, ENUM b) {                        \
-    return ENUM(unsigned(a) & unsigned(b));                                    \
-  }                                                                            \
-  MDBX_CXX01_CONSTEXPR ENUM operator&(ENUM a, unsigned b) {                    \
-    return ENUM(unsigned(a) & b);                                              \
-  }                                                                            \
-  MDBX_CXX01_CONSTEXPR ENUM operator&(unsigned a, ENUM b) {                    \
-    return ENUM(a & unsigned(b));                                              \
-  }                                                                            \
-  MDBX_CXX14_CONSTEXPR ENUM &operator&=(ENUM &a, ENUM b) { return a = a & b; } \
-  MDBX_CXX14_CONSTEXPR ENUM &operator&=(ENUM &a, unsigned b) {                 \
-    return a = a & b;                                                          \
-  }                                                                            \
-  MDBX_CXX01_CONSTEXPR unsigned operator~(ENUM a) { return ~unsigned(a); }     \
-  MDBX_CXX01_CONSTEXPR ENUM operator^(ENUM a, ENUM b) {                        \
-    return ENUM(unsigned(a) ^ unsigned(b));                                    \
-  }                                                                            \
-  MDBX_CXX14_CONSTEXPR ENUM &operator^=(ENUM &a, ENUM b) { return a = a ^ b; } \
-  }
-#else /* __cplusplus */
-/* nope for C since it always allows these operators for enums */
-#define DEFINE_ENUM_FLAG_OPERATORS(ENUM)
-#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 1
-#endif /* !__cplusplus */
-
-#elif !defined(CONSTEXPR_ENUM_FLAGS_OPERATIONS)
-
-#ifdef __cplusplus
-/* DEFINE_ENUM_FLAG_OPERATORS may be defined broken as in the Windows SDK */
-#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 0
-#else
-/* C always allows these operators for enums */
-#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 1
-#endif
-
-#endif /* DEFINE_ENUM_FLAG_OPERATORS */
-
-/** @} end of Common Macros */
-
-/*----------------------------------------------------------------------------*/
-
-/** \addtogroup c_api
- * @{ */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* MDBX version 0.9.x */
-#define MDBX_VERSION_MAJOR 0
-#define MDBX_VERSION_MINOR 9
-
-#ifndef LIBMDBX_API
-#if defined(LIBMDBX_EXPORTS)
-#define LIBMDBX_API __dll_export
-#elif defined(LIBMDBX_IMPORTS)
-#define LIBMDBX_API __dll_import
-#else
-#define LIBMDBX_API
-#endif
-#endif /* LIBMDBX_API */
-
-#ifdef __cplusplus
-#if defined(__clang__) || __has_attribute(type_visibility)
-#define LIBMDBX_API_TYPE LIBMDBX_API __attribute__((type_visibility("default")))
-#else
-#define LIBMDBX_API_TYPE LIBMDBX_API
-#endif
-#else
-#define LIBMDBX_API_TYPE
-#endif /* LIBMDBX_API_TYPE */
-
-#if defined(LIBMDBX_IMPORTS)
-#define LIBMDBX_VERINFO_API __dll_import
-#else
-#define LIBMDBX_VERINFO_API __dll_export
-#endif /* LIBMDBX_VERINFO_API */
-
-/** \brief libmdbx version information */
-extern LIBMDBX_VERINFO_API const struct MDBX_version_info {
-  uint8_t major;     /**< Major version number */
-  uint8_t minor;     /**< Minor version number */
-  uint16_t release;  /**< Release number of Major.Minor */
-  uint32_t revision; /**< Revision number of Release */
-  struct {
-    const char *datetime; /**< committer date, strict ISO-8601 format */
-    const char *tree;     /**< commit hash (hexadecimal digits) */
-    const char *commit;   /**< tree hash, i.e. digest of the source code */
-    const char *describe; /**< git-describe string */
-  } git;                  /**< source information from git */
-  const char *sourcery;   /**< sourcery anchor for pinning */
-} /** \brief libmdbx version information */ mdbx_version;
-
-/** \brief libmdbx build information
- * \attention Some strings could be NULL in case no corresponding information
- *            was provided at build time (i.e. flags). */
-extern LIBMDBX_VERINFO_API const struct MDBX_build_info {
-  const char *datetime; /**< build timestamp (ISO-8601 or __DATE__ __TIME__) */
-  const char *target;   /**< cpu/arch-system-config triplet */
-  const char *options;  /**< mdbx-related options */
-  const char *compiler; /**< compiler */
-  const char *flags;    /**< CFLAGS and CXXFLAGS */
-} /** \brief libmdbx build information */ mdbx_build;
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !MDBX_BUILD_SHARED_LIBRARY
-
-/* MDBX internally uses global and thread local storage destructors to
- * automatically (de)initialization, releasing reader lock table slots
- * and so on.
- *
- * If MDBX builded as a DLL this is done out-of-the-box by DllEntry() function,
- * which called automatically by Windows core with passing corresponding reason
- * argument.
- *
- * Otherwise, if MDBX was builded not as a DLL, some black magic
- * may be required depending of Windows version:
- *  - Modern Windows versions, including Windows Vista and later, provides
- *    support for "TLS Directory" (e.g .CRT$XL[A-Z] sections in executable
- *    or dll file). In this case, MDBX capable of doing all automatically,
- *    and you do not need to call mdbx_dll_handler().
- *  - Obsolete versions of Windows, prior to Windows Vista, REQUIRES calling
- *    mdbx_dll_handler() manually from corresponding DllMain() or WinMain()
- *    of your DLL or application.
- *  - This behavior is under control of the MODX_CONFIG_MANUAL_TLS_CALLBACK
- *    option, which is determined by default according to the target version
- *    of Windows at build time.
- *    But you may override MODX_CONFIG_MANUAL_TLS_CALLBACK in special cases.
- *
- * Therefore, building MDBX as a DLL is recommended for all version of Windows.
- * So, if you doubt, just build MDBX as the separate DLL and don't worry. */
-
-#ifndef MDBX_CONFIG_MANUAL_TLS_CALLBACK
-#if defined(_WIN32_WINNT_VISTA) && WINVER >= _WIN32_WINNT_VISTA
-/* As described above mdbx_dll_handler() is NOT needed forWindows Vista
- * and later. */
-#define MDBX_CONFIG_MANUAL_TLS_CALLBACK 0
-#else
-/* As described above mdbx_dll_handler() IS REQUIRED for Windows versions
- * prior to Windows Vista. */
-#define MDBX_CONFIG_MANUAL_TLS_CALLBACK 1
-#endif
-#endif /* MDBX_CONFIG_MANUAL_TLS_CALLBACK */
-
-#if MDBX_CONFIG_MANUAL_TLS_CALLBACK
-void LIBMDBX_API NTAPI mdbx_dll_handler(PVOID module, DWORD reason,
-                                        PVOID reserved);
-#endif /* MDBX_CONFIG_MANUAL_TLS_CALLBACK */
-#endif /* !MDBX_BUILD_SHARED_LIBRARY */
-#endif /* Windows */
-
-/* OPACITY STRUCTURES *********************************************************/
-
-/** \brief Opaque structure for a database environment.
- * \details An environment supports multiple key-value sub-databases (aka
- * key-value spaces or tables), all residing in the same shared-memory map.
- * \see mdbx_env_create() \see mdbx_env_close() */
-#ifndef __cplusplus
-typedef struct MDBX_env MDBX_env;
-#else
-struct MDBX_env;
-#endif
-
-/** \brief Opaque structure for a transaction handle.
- * \ingroup c_transactions
- * \details All database operations require a transaction handle. Transactions
- * may be read-only or read-write.
- * \see mdbx_txn_begin() \see mdbx_txn_commit() \see mdbx_txn_abort() */
-#ifndef __cplusplus
-typedef struct MDBX_txn MDBX_txn;
-#else
-struct MDBX_txn;
-#endif
-
-/** \brief A handle for an individual database (key-value spaces) in the
- * environment. \ingroup c_dbi \details Zero handle is used internally (hidden
- * Garbage Collection DB). So, any valid DBI-handle great than 0 and less than
- * or equal \ref MDBX_MAX_DBI. \see mdbx_dbi_open() \see mdbx_dbi_close() */
-typedef uint32_t MDBX_dbi;
-
-/** \brief Opaque structure for navigating through a database
- * \ingroup c_cursors
- * \see mdbx_cursor_create() \see mdbx_cursor_bind() \see mdbx_cursor_close()
- */
-#ifndef __cplusplus
-typedef struct MDBX_cursor MDBX_cursor;
-#else
-struct MDBX_cursor;
-#endif
-
-/** \brief Generic structure used for passing keys and data in and out of the
- * database.
- * \anchor MDBX_val \see mdbx::slice \see mdbx::buffer
- *
- * \details Values returned from the database are valid only until a subsequent
- * update operation, or the end of the transaction. Do not modify or
- * free them, they commonly point into the database itself.
- *
- * Key sizes must be between 0 and \ref mdbx_env_get_maxkeysize() inclusive.
- * The same applies to data sizes in databases with the \ref MDBX_DUPSORT flag.
- * Other data items can in theory be from 0 to \ref MDBX_MAXDATASIZE bytes long.
- *
- * \note The notable difference between MDBX and LMDB is that MDBX support zero
- * length keys. */
-#ifndef HAVE_STRUCT_IOVEC
-struct iovec {
-  void *iov_base; /**< pointer to some data */
-  size_t iov_len; /**< the length of data in bytes */
-};
-#define HAVE_STRUCT_IOVEC
-#endif /* HAVE_STRUCT_IOVEC */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-/* The `iov_len` is signed on Sun/Solaris.
- * So define custom MDBX_val to avoid a lot of warnings. */
-struct MDBX_val {
-  void *iov_base; /**< pointer to some data */
-  size_t iov_len; /**< the length of data in bytes */
-};
-#ifndef __cplusplus
-typedef struct MDBX_val MDBX_val;
-#endif
-#else  /* SunOS */
-typedef struct iovec MDBX_val;
-#endif /* ! SunOS */
-
-enum MDBX_constants {
-  /** The hard limit for DBI handles */
-  MDBX_MAX_DBI = UINT32_C(32765),
-
-  /** The maximum size of a data item. */
-  MDBX_MAXDATASIZE = UINT32_C(0x7fff0000),
-
-  /** The minimal database page size in bytes. */
-  MDBX_MIN_PAGESIZE = 256,
-
-  /** The maximal database page size in bytes. */
-  MDBX_MAX_PAGESIZE = 65536,
-};
-
-/* THE FILES *******************************************************************
- * At the file system level, the environment corresponds to a pair of files. */
-
-/** \brief The name of the lock file in the environment */
-#define MDBX_LOCKNAME "/mdbx.lck"
-/** \brief The name of the data file in the environment */
-#define MDBX_DATANAME "/mdbx.dat"
-
-/** \brief The suffix of the lock file when \ref MDBX_NOSUBDIR is used */
-#define MDBX_LOCK_SUFFIX "-lck"
-
-/* DEBUG & LOGGING ************************************************************/
-
-/** \addtogroup c_debug
- * \note Most of debug feature enabled only when libmdbx builded with
- * \ref MDBX_DEBUG build option. @{ */
-
-/** Log level (requires build libmdbx with \ref MDBX_DEBUG option) */
-enum MDBX_log_level_t {
-  /** Critical conditions, i.e. assertion failures */
-  MDBX_LOG_FATAL = 0,
-
-  /** Enables logging for error conditions and \ref MDBX_LOG_FATAL */
-  MDBX_LOG_ERROR = 1,
-
-  /** Enables logging for warning conditions and \ref MDBX_LOG_ERROR ...
-      \ref MDBX_LOG_FATAL */
-  MDBX_LOG_WARN = 2,
-
-  /** Enables logging for normal but significant condition and
-      \ref MDBX_LOG_WARN ... \ref MDBX_LOG_FATAL */
-  MDBX_LOG_NOTICE = 3,
-
-  /** Enables logging for verbose informational and \ref MDBX_LOG_NOTICE ...
-      \ref MDBX_LOG_FATAL */
-  MDBX_LOG_VERBOSE = 4,
-
-  /** Enables logging for debug-level messages and \ref MDBX_LOG_VERBOSE ...
-      \ref MDBX_LOG_FATAL */
-  MDBX_LOG_DEBUG = 5,
-
-  /** Enables logging for trace debug-level messages and \ref MDBX_LOG_DEBUG ...
-      \ref MDBX_LOG_FATAL */
-  MDBX_LOG_TRACE = 6,
-
-  /** Enables extra debug-level messages (dump pgno lists)
-      and all other log-messages */
-  MDBX_LOG_EXTRA = 7,
-
-  /** for \ref mdbx_setup_debug() only: Don't change current settings */
-  MDBX_LOG_DONTCHANGE = -1
-};
-#ifndef __cplusplus
-typedef enum MDBX_log_level_t MDBX_log_level_t;
-#endif
-
-/** \brief Runtime debug flags
- *
- * \details `MDBX_DBG_DUMP` and `MDBX_DBG_LEGACY_MULTIOPEN` always have an
- * effect, but `MDBX_DBG_ASSERT`, `MDBX_DBG_AUDIT` and `MDBX_DBG_JITTER` only if
- * libmdbx builded with \ref MDBX_DEBUG. */
-enum MDBX_debug_flags_t {
-  /** Enable assertion checks.
-   * Requires build with \ref MDBX_DEBUG > 0 */
-  MDBX_DBG_ASSERT = 1,
-
-  /** Enable pages usage audit at commit transactions.
-   * Requires build with \ref MDBX_DEBUG > 0 */
-  MDBX_DBG_AUDIT = 2,
-
-  /** Enable small random delays in critical points.
-   * Requires build with \ref MDBX_DEBUG > 0 */
-  MDBX_DBG_JITTER = 4,
-
-  /** Include or not meta-pages in coredump files.
-   * May affect performance in \ref MDBX_WRITEMAP mode */
-  MDBX_DBG_DUMP = 8,
-
-  /** Allow multi-opening environment(s) */
-  MDBX_DBG_LEGACY_MULTIOPEN = 16,
-
-  /** Allow read and write transactions overlapping for the same thread */
-  MDBX_DBG_LEGACY_OVERLAP = 32,
-
-  /** for mdbx_setup_debug() only: Don't change current settings */
-  MDBX_DBG_DONTCHANGE = -1
-};
-#ifndef __cplusplus
-typedef enum MDBX_debug_flags_t MDBX_debug_flags_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_debug_flags_t)
-#endif
-
-/** \brief A debug-logger callback function,
- * called before printing the message and aborting.
- * \see mdbx_setup_debug()
- *
- * \param [in] env  An environment handle returned by \ref mdbx_env_create().
- * \param [in] msg  The assertion message, not including newline. */
-typedef void MDBX_debug_func(MDBX_log_level_t loglevel, const char *function,
-                             int line, const char *fmt,
-                             va_list args) MDBX_CXX17_NOEXCEPT;
-
-/** \brief The "don't change `logger`" value for mdbx_setup_debug() */
-#define MDBX_LOGGER_DONTCHANGE ((MDBX_debug_func *)(intptr_t)-1)
-
-/** \brief Setup global log-level, debug options and debug logger.
- * \returns The previously `debug_flags` in the 0-15 bits
- *          and `log_level` in the 16-31 bits. */
-LIBMDBX_API int mdbx_setup_debug(MDBX_log_level_t log_level,
-                                 MDBX_debug_flags_t debug_flags,
-                                 MDBX_debug_func *logger);
-
-/** \brief A callback function for most MDBX assert() failures,
- * called before printing the message and aborting.
- * \see mdbx_env_set_assert()
- *
- * \param [in] env  An environment handle returned by mdbx_env_create().
- * \param [in] msg  The assertion message, not including newline. */
-typedef void MDBX_assert_func(const MDBX_env *env, const char *msg,
-                              const char *function,
-                              unsigned line) MDBX_CXX17_NOEXCEPT;
-
-/** \brief Set or reset the assert() callback of the environment.
- *
- * Does nothing if libmdbx was built with MDBX_DEBUG=0 or with NDEBUG,
- * and will return `MDBX_ENOSYS` in such case.
- *
- * \param [in] env   An environment handle returned by mdbx_env_create().
- * \param [in] func  An MDBX_assert_func function, or 0.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_set_assert(MDBX_env *env, MDBX_assert_func *func);
-
-/** \brief Dump given MDBX_val to the buffer
- *
- * Dumps it as string if value is printable (all bytes in the range 0x20..0x7E),
- * otherwise made hexadecimal dump. Requires at least 4 byte length buffer.
- *
- * \returns One of:
- *  - NULL if given buffer size less than 4 bytes;
- *  - pointer to constant string if given value NULL or empty;
- *  - otherwise pointer to given buffer. */
-LIBMDBX_API const char *mdbx_dump_val(const MDBX_val *key, char *const buf,
-                                      const size_t bufsize);
-
-/** \brief Panics with message and causes abnormal process termination. */
-LIBMDBX_API void mdbx_panic(const char *fmt, ...) MDBX_PRINTF_ARGS(1, 2);
-
-/** @} end of logging & debug */
-
-/** \brief Environment flags
- * \ingroup c_opening
- * \anchor env_flags
- * \see mdbx_env_open() \see mdbx_env_set_flags() */
-enum MDBX_env_flags_t {
-  MDBX_ENV_DEFAULTS = 0,
-
-  /** No environment directory.
-   *
-   * By default, MDBX creates its environment in a directory whose pathname is
-   * given in path, and creates its data and lock files under that directory.
-   * With this option, path is used as-is for the database main data file.
-   * The database lock file is the path with "-lck" appended.
-   *
-   * - with `MDBX_NOSUBDIR` = in a filesystem we have the pair of MDBX-files
-   *   which names derived from given pathname by appending predefined suffixes.
-   *
-   * - without `MDBX_NOSUBDIR` = in a filesystem we have the MDBX-directory with
-   *   given pathname, within that a pair of MDBX-files with predefined names.
-   *
-   * This flag affects only at new environment creating by \ref mdbx_env_open(),
-   * otherwise at opening an existing environment libmdbx will choice this
-   * automatically. */
-  MDBX_NOSUBDIR = UINT32_C(0x4000),
-
-  /** Read only mode.
-   *
-   * Open the environment in read-only mode. No write operations will be
-   * allowed. MDBX will still modify the lock file - except on read-only
-   * filesystems, where MDBX does not use locks.
-   *
-   * - with `MDBX_RDONLY` = open environment in read-only mode.
-   *   MDBX supports pure read-only mode (i.e. without opening LCK-file) only
-   *   when environment directory and/or both files are not writable (and the
-   *   LCK-file may be missing). In such case allowing file(s) to be placed
-   *   on a network read-only share.
-   *
-   * - without `MDBX_RDONLY` = open environment in read-write mode.
-   *
-   * This flag affects only at environment opening but can't be changed after.
-   */
-  MDBX_RDONLY = UINT32_C(0x20000),
-
-  /** Open environment in exclusive/monopolistic mode.
-   *
-   * `MDBX_EXCLUSIVE` flag can be used as a replacement for `MDB_NOLOCK`,
-   * which don't supported by MDBX.
-   * In this way, you can get the minimal overhead, but with the correct
-   * multi-process and multi-thread locking.
-   *
-   * - with `MDBX_EXCLUSIVE` = open environment in exclusive/monopolistic mode
-   *   or return \ref MDBX_BUSY if environment already used by other process.
-   *   The main feature of the exclusive mode is the ability to open the
-   *   environment placed on a network share.
-   *
-   * - without `MDBX_EXCLUSIVE` = open environment in cooperative mode,
-   *   i.e. for multi-process access/interaction/cooperation.
-   *   The main requirements of the cooperative mode are:
-   *
-   *   1. data files MUST be placed in the LOCAL file system,
-   *      but NOT on a network share.
-   *   2. environment MUST be opened only by LOCAL processes,
-   *      but NOT over a network.
-   *   3. OS kernel (i.e. file system and memory mapping implementation) and
-   *      all processes that open the given environment MUST be running
-   *      in the physically single RAM with cache-coherency. The only
-   *      exception for cache-consistency requirement is Linux on MIPS
-   *      architecture, but this case has not been tested for a long time).
-   *
-   * This flag affects only at environment opening but can't be changed after.
-   */
-  MDBX_EXCLUSIVE = UINT32_C(0x400000),
-
-  /** Using database/environment which already opened by another process(es).
-   *
-   * The `MDBX_ACCEDE` flag is useful to avoid \ref MDBX_INCOMPATIBLE error
-   * while opening the database/environment which is already used by another
-   * process(es) with unknown mode/flags. In such cases, if there is a
-   * difference in the specified flags (\ref MDBX_NOMETASYNC,
-   * \ref MDBX_SAFE_NOSYNC, \ref MDBX_UTTERLY_NOSYNC, \ref MDBX_LIFORECLAIM,
-   * \ref MDBX_COALESCE and \ref MDBX_NORDAHEAD), instead of returning an error,
-   * the database will be opened in a compatibility with the already used mode.
-   *
-   * `MDBX_ACCEDE` has no effect if the current process is the only one either
-   * opening the DB in read-only mode or other process(es) uses the DB in
-   * read-only mode. */
-  MDBX_ACCEDE = UINT32_C(0x40000000),
-
-  /** Map data into memory with write permission.
-   *
-   * Use a writeable memory map unless \ref MDBX_RDONLY is set. This uses fewer
-   * mallocs and requires much less work for tracking database pages, but
-   * loses protection from application bugs like wild pointer writes and other
-   * bad updates into the database. This may be slightly faster for DBs that
-   * fit entirely in RAM, but is slower for DBs larger than RAM. Also adds the
-   * possibility for stray application writes thru pointers to silently
-   * corrupt the database.
-   *
-   * - with `MDBX_WRITEMAP` = all data will be mapped into memory in the
-   *   read-write mode. This offers a significant performance benefit, since the
-   *   data will be modified directly in mapped memory and then flushed to disk
-   *   by single system call, without any memory management nor copying.
-   *
-   * - without `MDBX_WRITEMAP` = data will be mapped into memory in the
-   *   read-only mode. This requires stocking all modified database pages in
-   *   memory and then writing them to disk through file operations.
-   *
-   * \warning On the other hand, `MDBX_WRITEMAP` adds the possibility for stray
-   * application writes thru pointers to silently corrupt the database.
-   *
-   * \note The `MDBX_WRITEMAP` mode is incompatible with nested transactions,
-   * since this is unreasonable. I.e. nested transactions requires mallocation
-   * of database pages and more work for tracking ones, which neuters a
-   * performance boost caused by the `MDBX_WRITEMAP` mode.
-   *
-   * This flag affects only at environment opening but can't be changed after.
-   */
-  MDBX_WRITEMAP = UINT32_C(0x80000),
-
-  /** Tie reader locktable slots to read-only transactions
-   * instead of to threads.
-   *
-   * Don't use Thread-Local Storage, instead tie reader locktable slots to
-   * \ref MDBX_txn objects instead of to threads. So, \ref mdbx_txn_reset()
-   * keeps the slot reserved for the \ref MDBX_txn object. A thread may use
-   * parallel read-only transactions. And a read-only transaction may span
-   * threads if you synchronizes its use.
-   *
-   * Applications that multiplex many user threads over individual OS threads
-   * need this option. Such an application must also serialize the write
-   * transactions in an OS thread, since MDBX's write locking is unaware of
-   * the user threads.
-   *
-   * \note Regardless to `MDBX_NOTLS` flag a write transaction entirely should
-   * always be used in one thread from start to finish. MDBX checks this in a
-   * reasonable manner and return the \ref MDBX_THREAD_MISMATCH error in rules
-   * violation.
-   *
-   * This flag affects only at environment opening but can't be changed after.
-   */
-  MDBX_NOTLS = UINT32_C(0x200000),
-
-  /** Don't do readahead.
-   *
-   * Turn off readahead. Most operating systems perform readahead on read
-   * requests by default. This option turns it off if the OS supports it.
-   * Turning it off may help random read performance when the DB is larger
-   * than RAM and system RAM is full.
-   *
-   * By default libmdbx dynamically enables/disables readahead depending on
-   * the actual database size and currently available memory. On the other
-   * hand, such automation has some limitation, i.e. could be performed only
-   * when DB size changing but can't tracks and reacts changing a free RAM
-   * availability, since it changes independently and asynchronously.
-   *
-   * \note The mdbx_is_readahead_reasonable() function allows to quickly find
-   * out whether to use readahead or not based on the size of the data and the
-   * amount of available memory.
-   *
-   * This flag affects only at environment opening and can't be changed after.
-   */
-  MDBX_NORDAHEAD = UINT32_C(0x800000),
-
-  /** Don't initialize malloc'd memory before writing to datafile.
-   *
-   * Don't initialize malloc'd memory before writing to unused spaces in the
-   * data file. By default, memory for pages written to the data file is
-   * obtained using malloc. While these pages may be reused in subsequent
-   * transactions, freshly malloc'd pages will be initialized to zeroes before
-   * use. This avoids persisting leftover data from other code (that used the
-   * heap and subsequently freed the memory) into the data file.
-   *
-   * Note that many other system libraries may allocate and free memory from
-   * the heap for arbitrary uses. E.g., stdio may use the heap for file I/O
-   * buffers. This initialization step has a modest performance cost so some
-   * applications may want to disable it using this flag. This option can be a
-   * problem for applications which handle sensitive data like passwords, and
-   * it makes memory checkers like Valgrind noisy. This flag is not needed
-   * with \ref MDBX_WRITEMAP, which writes directly to the mmap instead of using
-   * malloc for pages. The initialization is also skipped if \ref MDBX_RESERVE
-   * is used; the caller is expected to overwrite all of the memory that was
-   * reserved in that case.
-   *
-   * This flag may be changed at any time using `mdbx_env_set_flags()`. */
-  MDBX_NOMEMINIT = UINT32_C(0x1000000),
-
-  /** Aims to coalesce a Garbage Collection items.
-   *
-   * With `MDBX_COALESCE` flag MDBX will aims to coalesce items while recycling
-   * a Garbage Collection. Technically, when possible short lists of pages
-   * will be combined into longer ones, but to fit on one database page. As a
-   * result, there will be fewer items in Garbage Collection and a page lists
-   * are longer, which slightly increases the likelihood of returning pages to
-   * Unallocated space and reducing the database file.
-   *
-   * This flag may be changed at any time using mdbx_env_set_flags(). */
-  MDBX_COALESCE = UINT32_C(0x2000000),
-
-  /** LIFO policy for recycling a Garbage Collection items.
-   *
-   * `MDBX_LIFORECLAIM` flag turns on LIFO policy for recycling a Garbage
-   * Collection items, instead of FIFO by default. On systems with a disk
-   * write-back cache, this can significantly increase write performance, up
-   * to several times in a best case scenario.
-   *
-   * LIFO recycling policy means that for reuse pages will be taken which became
-   * unused the lastest (i.e. just now or most recently). Therefore the loop of
-   * database pages circulation becomes as short as possible. In other words,
-   * the number of pages, that are overwritten in memory and on disk during a
-   * series of write transactions, will be as small as possible. Thus creates
-   * ideal conditions for the efficient operation of the disk write-back cache.
-   *
-   * \ref MDBX_LIFORECLAIM is compatible with all no-sync flags, but gives NO
-   * noticeable impact in combination with \ref MDBX_SAFE_NOSYNC or
-   * \ref MDBX_UTTERLY_NOSYNC. Because MDBX will reused pages only before the
-   * last "steady" MVCC-snapshot, i.e. the loop length of database pages
-   * circulation will be mostly defined by frequency of calling
-   * \ref mdbx_env_sync() rather than LIFO and FIFO difference.
-   *
-   * This flag may be changed at any time using mdbx_env_set_flags(). */
-  MDBX_LIFORECLAIM = UINT32_C(0x4000000),
-
-  /** Debugging option, fill/perturb released pages. */
-  MDBX_PAGEPERTURB = UINT32_C(0x8000000),
-
-  /* SYNC MODES****************************************************************/
-  /** \defgroup sync_modes SYNC MODES
-   *
-   * \attention Using any combination of \ref MDBX_SAFE_NOSYNC, \ref
-   * MDBX_NOMETASYNC and especially \ref MDBX_UTTERLY_NOSYNC is always a deal to
-   * reduce durability for gain write performance. You must know exactly what
-   * you are doing and what risks you are taking!
-   *
-   * \note for LMDB users: \ref MDBX_SAFE_NOSYNC is NOT similar to LMDB_NOSYNC,
-   * but \ref MDBX_UTTERLY_NOSYNC is exactly match LMDB_NOSYNC. See details
-   * below.
-   *
-   * THE SCENE:
-   * - The DAT-file contains several MVCC-snapshots of B-tree at same time,
-   *   each of those B-tree has its own root page.
-   * - Each of meta pages at the beginning of the DAT file contains a
-   *   pointer to the root page of B-tree which is the result of the particular
-   *   transaction, and a number of this transaction.
-   * - For data durability, MDBX must first write all MVCC-snapshot data
-   *   pages and ensure that are written to the disk, then update a meta page
-   *   with the new transaction number and a pointer to the corresponding new
-   *   root page, and flush any buffers yet again.
-   * - Thus during commit a I/O buffers should be flushed to the disk twice;
-   *   i.e. fdatasync(), FlushFileBuffers() or similar syscall should be
-   *   called twice for each commit. This is very expensive for performance,
-   *   but guaranteed durability even on unexpected system failure or power
-   *   outage. Of course, provided that the operating system and the
-   *   underlying hardware (e.g. disk) work correctly.
-   *
-   * TRADE-OFF:
-   * By skipping some stages described above, you can significantly benefit in
-   * speed, while partially or completely losing in the guarantee of data
-   * durability and/or consistency in the event of system or power failure.
-   * Moreover, if for any reason disk write order is not preserved, then at
-   * moment of a system crash, a meta-page with a pointer to the new B-tree may
-   * be written to disk, while the itself B-tree not yet. In that case, the
-   * database will be corrupted!
-   *
-   * \see MDBX_SYNC_DURABLE \see MDBX_NOMETASYNC \see MDBX_SAFE_NOSYNC
-   * \see MDBX_UTTERLY_NOSYNC
-   *
-   * @{ */
-
-  /** Default robust and durable sync mode.
-   *
-   * Metadata is written and flushed to disk after a data is written and
-   * flushed, which guarantees the integrity of the database in the event
-   * of a crash at any time.
-   *
-   * \attention Please do not use other modes until you have studied all the
-   * details and are sure. Otherwise, you may lose your users' data, as happens
-   * in [Miranda NG](https://www.miranda-ng.org/) messenger. */
-  MDBX_SYNC_DURABLE = 0,
-
-  /** Don't sync the meta-page after commit.
-   *
-   * Flush system buffers to disk only once per transaction commit, omit the
-   * metadata flush. Defer that until the system flushes files to disk,
-   * or next non-\ref MDBX_RDONLY commit or \ref mdbx_env_sync(). Depending on
-   * the platform and hardware, with \ref MDBX_NOMETASYNC you may get a doubling
-   * of write performance.
-   *
-   * This trade-off maintains database integrity, but a system crash may
-   * undo the last committed transaction. I.e. it preserves the ACI
-   * (atomicity, consistency, isolation) but not D (durability) database
-   * property.
-   *
-   * `MDBX_NOMETASYNC` flag may be changed at any time using
-   * \ref mdbx_env_set_flags() or by passing to \ref mdbx_txn_begin() for
-   * particular write transaction. \see sync_modes */
-  MDBX_NOMETASYNC = UINT32_C(0x40000),
-
-  /** Don't sync anything but keep previous steady commits.
-   *
-   * Like \ref MDBX_UTTERLY_NOSYNC the `MDBX_SAFE_NOSYNC` flag disable similarly
-   * flush system buffers to disk when committing a transaction. But there is a
-   * huge difference in how are recycled the MVCC snapshots corresponding to
-   * previous "steady" transactions (see below).
-   *
-   * With \ref MDBX_WRITEMAP the `MDBX_SAFE_NOSYNC` instructs MDBX to use
-   * asynchronous mmap-flushes to disk. Asynchronous mmap-flushes means that
-   * actually all writes will scheduled and performed by operation system on it
-   * own manner, i.e. unordered. MDBX itself just notify operating system that
-   * it would be nice to write data to disk, but no more.
-   *
-   * Depending on the platform and hardware, with `MDBX_SAFE_NOSYNC` you may get
-   * a multiple increase of write performance, even 10 times or more.
-   *
-   * In contrast to \ref MDBX_UTTERLY_NOSYNC mode, with `MDBX_SAFE_NOSYNC` flag
-   * MDBX will keeps untouched pages within B-tree of the last transaction
-   * "steady" which was synced to disk completely. This has big implications for
-   * both data durability and (unfortunately) performance:
-   *  - a system crash can't corrupt the database, but you will lose the last
-   *    transactions; because MDBX will rollback to last steady commit since it
-   *    kept explicitly.
-   *  - the last steady transaction makes an effect similar to "long-lived" read
-   *    transaction (see above in the \ref restrictions section) since prevents
-   *    reuse of pages freed by newer write transactions, thus the any data
-   *    changes will be placed in newly allocated pages.
-   *  - to avoid rapid database growth, the system will sync data and issue
-   *    a steady commit-point to resume reuse pages, each time there is
-   *    insufficient space and before increasing the size of the file on disk.
-   *
-   * In other words, with `MDBX_SAFE_NOSYNC` flag MDBX insures you from the
-   * whole database corruption, at the cost increasing database size and/or
-   * number of disk IOPs. So, `MDBX_SAFE_NOSYNC` flag could be used with
-   * \ref mdbx_env_sync() as alternatively for batch committing or nested
-   * transaction (in some cases). As well, auto-sync feature exposed by
-   * \ref mdbx_env_set_syncbytes() and \ref mdbx_env_set_syncperiod() functions
-   * could be very useful with `MDBX_SAFE_NOSYNC` flag.
-   *
-   * The number and volume of of disk IOPs with MDBX_SAFE_NOSYNC flag will
-   * exactly the as without any no-sync flags. However, you should expect a
-   * larger process's [work set](https://bit.ly/2kA2tFX) and significantly worse
-   * a [locality of reference](https://bit.ly/2mbYq2J), due to the more
-   * intensive allocation of previously unused pages and increase the size of
-   * the database.
-   *
-   * `MDBX_SAFE_NOSYNC` flag may be changed at any time using
-   * \ref mdbx_env_set_flags() or by passing to \ref mdbx_txn_begin() for
-   * particular write transaction. */
-  MDBX_SAFE_NOSYNC = UINT32_C(0x10000),
-
-  /** \deprecated Please use \ref MDBX_SAFE_NOSYNC instead of `MDBX_MAPASYNC`.
-   *
-   * Since version 0.9.x the `MDBX_MAPASYNC` is deprecated and has the same
-   * effect as \ref MDBX_SAFE_NOSYNC with \ref MDBX_WRITEMAP. This just API
-   * simplification is for convenience and clarity. */
-  MDBX_MAPASYNC = MDBX_SAFE_NOSYNC,
-
-  /** Don't sync anything and wipe previous steady commits.
-   *
-   * Don't flush system buffers to disk when committing a transaction. This
-   * optimization means a system crash can corrupt the database, if buffers are
-   * not yet flushed to disk. Depending on the platform and hardware, with
-   * `MDBX_UTTERLY_NOSYNC` you may get a multiple increase of write performance,
-   * even 100 times or more.
-   *
-   * If the filesystem preserves write order (which is rare and never provided
-   * unless explicitly noted) and the \ref MDBX_WRITEMAP and \ref
-   * MDBX_LIFORECLAIM flags are not used, then a system crash can't corrupt the
-   * database, but you can lose the last transactions, if at least one buffer is
-   * not yet flushed to disk. The risk is governed by how often the system
-   * flushes dirty buffers to disk and how often \ref mdbx_env_sync() is called.
-   * So, transactions exhibit ACI (atomicity, consistency, isolation) properties
-   * and only lose `D` (durability). I.e. database integrity is maintained, but
-   * a system crash may undo the final transactions.
-   *
-   * Otherwise, if the filesystem not preserves write order (which is
-   * typically) or \ref MDBX_WRITEMAP or \ref MDBX_LIFORECLAIM flags are used,
-   * you should expect the corrupted database after a system crash.
-   *
-   * So, most important thing about `MDBX_UTTERLY_NOSYNC`:
-   *  - a system crash immediately after commit the write transaction
-   *    high likely lead to database corruption.
-   *  - successful completion of mdbx_env_sync(force = true) after one or
-   *    more committed transactions guarantees consistency and durability.
-   *  - BUT by committing two or more transactions you back database into
-   *    a weak state, in which a system crash may lead to database corruption!
-   *    In case single transaction after mdbx_env_sync, you may lose transaction
-   *    itself, but not a whole database.
-   *
-   * Nevertheless, `MDBX_UTTERLY_NOSYNC` provides "weak" durability in case
-   * of an application crash (but no durability on system failure), and
-   * therefore may be very useful in scenarios where data durability is
-   * not required over a system failure (e.g for short-lived data), or if you
-   * can take such risk.
-   *
-   * `MDBX_UTTERLY_NOSYNC` flag may be changed at any time using
-   * \ref mdbx_env_set_flags(), but don't has effect if passed to
-   * \ref mdbx_txn_begin() for particular write transaction. \see sync_modes */
-  MDBX_UTTERLY_NOSYNC = MDBX_SAFE_NOSYNC | UINT32_C(0x100000),
-
-  /** @} end of SYNC MODES */
-};
-#ifndef __cplusplus
-/** \ingroup c_opening */
-typedef enum MDBX_env_flags_t MDBX_env_flags_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_env_flags_t)
-#endif
-
-/** Transaction flags
- * \ingroup c_transactions
- * \anchor txn_flags
- * \see mdbx_txn_begin() \see mdbx_txn_flags() */
-enum MDBX_txn_flags_t {
-  /** Start read-write transaction.
-   *
-   * Only one write transaction may be active at a time. Writes are fully
-   * serialized, which guarantees that writers can never deadlock. */
-  MDBX_TXN_READWRITE = 0,
-
-  /** Start read-only transaction.
-   *
-   * There can be multiple read-only transactions simultaneously that do not
-   * block each other and a write transactions. */
-  MDBX_TXN_RDONLY = MDBX_RDONLY,
-
-/** Prepare but not start read-only transaction.
- *
- * Transaction will not be started immediately, but created transaction handle
- * will be ready for use with \ref mdbx_txn_renew(). This flag allows to
- * preallocate memory and assign a reader slot, thus avoiding these operations
- * at the next start of the transaction. */
-#if CONSTEXPR_ENUM_FLAGS_OPERATIONS || defined(DOXYGEN)
-  MDBX_TXN_RDONLY_PREPARE = MDBX_RDONLY | MDBX_NOMEMINIT,
-#else
-  MDBX_TXN_RDONLY_PREPARE = uint32_t(MDBX_RDONLY) | uint32_t(MDBX_NOMEMINIT),
-#endif
-
-  /** Do not block when starting a write transaction. */
-  MDBX_TXN_TRY = UINT32_C(0x10000000),
-
-  /** Exactly the same as \ref MDBX_NOMETASYNC,
-   * but for this transaction only */
-  MDBX_TXN_NOMETASYNC = MDBX_NOMETASYNC,
-
-  /** Exactly the same as \ref MDBX_SAFE_NOSYNC,
-   * but for this transaction only */
-  MDBX_TXN_NOSYNC = MDBX_SAFE_NOSYNC
-};
-#ifndef __cplusplus
-typedef enum MDBX_txn_flags_t MDBX_txn_flags_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_txn_flags_t)
-#endif
-
-/** \brief Database flags
- * \ingroup c_dbi
- * \anchor db_flags
- * \see mdbx_dbi_open() */
-enum MDBX_db_flags_t {
-  MDBX_DB_DEFAULTS = 0,
-
-  /** Use reverse string keys */
-  MDBX_REVERSEKEY = UINT32_C(0x02),
-
-  /** Use sorted duplicates, i.e. allow multi-values */
-  MDBX_DUPSORT = UINT32_C(0x04),
-
-  /** Numeric keys in native byte order either uint32_t or uint64_t. The keys
-   * must all be of the same size and must be aligned while passing as
-   * arguments. */
-  MDBX_INTEGERKEY = UINT32_C(0x08),
-
-  /** With \ref MDBX_DUPSORT; sorted dup items have fixed size */
-  MDBX_DUPFIXED = UINT32_C(0x10),
-
-  /** With \ref MDBX_DUPSORT and with \ref MDBX_DUPFIXED; dups are fixed size
-   * \ref MDBX_INTEGERKEY -style integers. The data values must all be of the
-   * same size and must be aligned while passing as arguments. */
-  MDBX_INTEGERDUP = UINT32_C(0x20),
-
-  /** With \ref MDBX_DUPSORT; use reverse string comparison */
-  MDBX_REVERSEDUP = UINT32_C(0x40),
-
-  /** Create DB if not already existing */
-  MDBX_CREATE = UINT32_C(0x40000),
-
-  /** Opens an existing sub-database created with unknown flags.
-   *
-   * The `MDBX_DB_ACCEDE` flag is intend to open a existing sub-database which
-   * was created with unknown flags (\ref MDBX_REVERSEKEY, \ref MDBX_DUPSORT,
-   * \ref MDBX_INTEGERKEY, \ref MDBX_DUPFIXED, \ref MDBX_INTEGERDUP and
-   * \ref MDBX_REVERSEDUP).
-   *
-   * In such cases, instead of returning the \ref MDBX_INCOMPATIBLE error, the
-   * sub-database will be opened with flags which it was created, and then an
-   * application could determine the actual flags by \ref mdbx_dbi_flags(). */
-  MDBX_DB_ACCEDE = MDBX_ACCEDE
-};
-#ifndef __cplusplus
-/** \ingroup c_dbi */
-typedef enum MDBX_db_flags_t MDBX_db_flags_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_db_flags_t)
-#endif
-
-/** \brief Data changing flags
- * \ingroup c_crud
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- * \see mdbx_put() \see mdbx_cursor_put() \see mdbx_replace() */
-enum MDBX_put_flags_t {
-  /** Upsertion by default (without any other flags) */
-  MDBX_UPSERT = 0,
-
-  /** For insertion: Don't write if the key already exists. */
-  MDBX_NOOVERWRITE = UINT32_C(0x10),
-
-  /** Has effect only for \ref MDBX_DUPSORT databases.
-   * For upsertion: don't write if the key-value pair already exist.
-   * For deletion: remove all values for key. */
-  MDBX_NODUPDATA = UINT32_C(0x20),
-
-  /** For upsertion: overwrite the current key/data pair.
-   * MDBX allows this flag for \ref mdbx_put() for explicit overwrite/update
-   * without insertion.
-   * For deletion: remove only single entry at the current cursor position. */
-  MDBX_CURRENT = UINT32_C(0x40),
-
-  /** Has effect only for \ref MDBX_DUPSORT databases.
-   * For deletion: remove all multi-values (aka duplicates) for given key.
-   * For upsertion: replace all multi-values for given key with a new one. */
-  MDBX_ALLDUPS = UINT32_C(0x80),
-
-  /** For upsertion: Just reserve space for data, don't copy it.
-   * Return a pointer to the reserved space. */
-  MDBX_RESERVE = UINT32_C(0x10000),
-
-  /** Data is being appended.
-   * Don't split full pages, continue on a new instead. */
-  MDBX_APPEND = UINT32_C(0x20000),
-
-  /** Has effect only for \ref MDBX_DUPSORT databases.
-   * Duplicate data is being appended.
-   * Don't split full pages, continue on a new instead. */
-  MDBX_APPENDDUP = UINT32_C(0x40000),
-
-  /** Only for \ref MDBX_DUPFIXED.
-   * Store multiple data items in one call. */
-  MDBX_MULTIPLE = UINT32_C(0x80000)
-};
-#ifndef __cplusplus
-/** \ingroup c_crud */
-typedef enum MDBX_put_flags_t MDBX_put_flags_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_put_flags_t)
-#endif
-
-/** \brief Environment copy flags
- * \ingroup c_extra
- * \see mdbx_env_copy() \see mdbx_env_copy2fd() */
-enum MDBX_copy_flags_t {
-  MDBX_CP_DEFAULTS = 0,
-
-  /** Copy with compactification: Omit free space from copy and renumber all
-   * pages sequentially */
-  MDBX_CP_COMPACT = 1u,
-
-  /** Force to make resizeable copy, i.e. dynamic size instead of fixed */
-  MDBX_CP_FORCE_DYNAMIC_SIZE = 2u
-};
-#ifndef __cplusplus
-/** \ingroup c_extra */
-typedef enum MDBX_copy_flags_t MDBX_copy_flags_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_copy_flags_t)
-#endif
-
-/** \brief Cursor operations
- * \ingroup c_cursors
- * This is the set of all operations for retrieving data using a cursor.
- * \see mdbx_cursor_set() */
-enum MDBX_cursor_op {
-  /** Position at first key/data item */
-  MDBX_FIRST,
-
-  /** \ref MDBX_DUPSORT -only: Position at first data item of current key. */
-  MDBX_FIRST_DUP,
-
-  /** \ref MDBX_DUPSORT -only: Position at key/data pair. */
-  MDBX_GET_BOTH,
-
-  /** \ref MDBX_DUPSORT -only: Position at given key and at first data greater
-   * than or equal to specified data. */
-  MDBX_GET_BOTH_RANGE,
-
-  /** Return key/data at current cursor position */
-  MDBX_GET_CURRENT,
-
-  /** \ref MDBX_DUPFIXED -only: Return up to a page of duplicate data items
-   * from current cursor position. Move cursor to prepare
-   * for \ref MDBX_NEXT_MULTIPLE. */
-  MDBX_GET_MULTIPLE,
-
-  /** Position at last key/data item */
-  MDBX_LAST,
-
-  /** \ref MDBX_DUPSORT -only: Position at last data item of current key. */
-  MDBX_LAST_DUP,
-
-  /** Position at next data item */
-  MDBX_NEXT,
-
-  /** \ref MDBX_DUPSORT -only: Position at next data item of current key. */
-  MDBX_NEXT_DUP,
-
-  /** \ref MDBX_DUPFIXED -only: Return up to a page of duplicate data items
-   * from next cursor position. Move cursor to prepare
-   * for `MDBX_NEXT_MULTIPLE`. */
-  MDBX_NEXT_MULTIPLE,
-
-  /** Position at first data item of next key */
-  MDBX_NEXT_NODUP,
-
-  /** Position at previous data item */
-  MDBX_PREV,
-
-  /** \ref MDBX_DUPSORT -only: Position at previous data item of current key. */
-  MDBX_PREV_DUP,
-
-  /** Position at last data item of previous key */
-  MDBX_PREV_NODUP,
-
-  /** Position at specified key */
-  MDBX_SET,
-
-  /** Position at specified key, return both key and data */
-  MDBX_SET_KEY,
-
-  /** Position at first key greater than or equal to specified key. */
-  MDBX_SET_RANGE,
-
-  /** \ref MDBX_DUPFIXED -only: Position at previous page and return up to
-   * a page of duplicate data items. */
-  MDBX_PREV_MULTIPLE,
-
-  /** Position at first key-value pair greater than or equal to specified,
-   * return both key and data, and the return code depends on a exact match.
-   *
-   * For non DUPSORT-ed collections this work the same to \ref MDBX_SET_RANGE,
-   * but returns \ref MDBX_SUCCESS if key found exactly and
-   * \ref MDBX_RESULT_TRUE if greater key was found.
-   *
-   * For DUPSORT-ed a data value is taken into account for duplicates,
-   * i.e. for a pairs/tuples of a key and an each data value of duplicates.
-   * Returns \ref MDBX_SUCCESS if key-value pair found exactly and
-   * \ref MDBX_RESULT_TRUE if the next pair was returned. */
-  MDBX_SET_LOWERBOUND
-};
-#ifndef __cplusplus
-/** \ingroup c_cursors */
-typedef enum MDBX_cursor_op MDBX_cursor_op;
-#endif
-
-/** \brief Errors and return codes
- * \ingroup c_err
- *
- * BerkeleyDB uses -30800 to -30999, we'll go under them
- * \see mdbx_strerror() \see mdbx_strerror_r() \see mdbx_liberr2str() */
-enum MDBX_error_t {
-  /** Successful result */
-  MDBX_SUCCESS = 0,
-
-  /** Alias for \ref MDBX_SUCCESS */
-  MDBX_RESULT_FALSE = MDBX_SUCCESS,
-
-  /** Successful result with special meaning or a flag */
-  MDBX_RESULT_TRUE = -1,
-
-  /** key/data pair already exists */
-  MDBX_KEYEXIST = -30799,
-
-  /** The first LMDB-compatible defined error code */
-  MDBX_FIRST_LMDB_ERRCODE = MDBX_KEYEXIST,
-
-  /** key/data pair not found (EOF) */
-  MDBX_NOTFOUND = -30798,
-
-  /** Requested page not found - this usually indicates corruption */
-  MDBX_PAGE_NOTFOUND = -30797,
-
-  /** Database is corrupted (page was wrong type and so on) */
-  MDBX_CORRUPTED = -30796,
-
-  /** Environment had fatal error,
-   * i.e. update of meta page failed and so on. */
-  MDBX_PANIC = -30795,
-
-  /** DB file version mismatch with libmdbx */
-  MDBX_VERSION_MISMATCH = -30794,
-
-  /** File is not a valid MDBX file */
-  MDBX_INVALID = -30793,
-
-  /** Environment mapsize reached */
-  MDBX_MAP_FULL = -30792,
-
-  /** Environment maxdbs reached */
-  MDBX_DBS_FULL = -30791,
-
-  /** Environment maxreaders reached */
-  MDBX_READERS_FULL = -30790,
-
-  /** Transaction has too many dirty pages, i.e transaction too big */
-  MDBX_TXN_FULL = -30788,
-
-  /** Cursor stack too deep - this usually indicates corruption,
-   * i.e branch-pages loop */
-  MDBX_CURSOR_FULL = -30787,
-
-  /** Page has not enough space - internal error */
-  MDBX_PAGE_FULL = -30786,
-
-  /** Database engine was unable to extend mapping, e.g. since address space
-   * is unavailable or busy. This can mean:
-   *  - Database size extended by other process beyond to environment mapsize
-   *    and engine was unable to extend mapping while starting read
-   *    transaction. Environment should be reopened to continue.
-   *  - Engine was unable to extend mapping during write transaction
-   *    or explicit call of \ref mdbx_env_set_geometry(). */
-  MDBX_UNABLE_EXTEND_MAPSIZE = -30785,
-
-  /** Environment or database is not compatible with the requested operation
-   * or the specified flags. This can mean:
-   *  - The operation expects an \ref MDBX_DUPSORT / \ref MDBX_DUPFIXED
-   *    database.
-   *  - Opening a named DB when the unnamed DB has \ref MDBX_DUPSORT /
-   *    \ref MDBX_INTEGERKEY.
-   *  - Accessing a data record as a database, or vice versa.
-   *  - The database was dropped and recreated with different flags. */
-  MDBX_INCOMPATIBLE = -30784,
-
-  /** Invalid reuse of reader locktable slot,
-   * e.g. read-transaction already run for current thread */
-  MDBX_BAD_RSLOT = -30783,
-
-  /** Transaction is not valid for requested operation,
-   * e.g. had errored and be must aborted, has a child, or is invalid */
-  MDBX_BAD_TXN = -30782,
-
-  /** Invalid size or alignment of key or data for target database,
-   * either invalid subDB name */
-  MDBX_BAD_VALSIZE = -30781,
-
-  /** The specified DBI-handle is invalid
-   * or changed by another thread/transaction */
-  MDBX_BAD_DBI = -30780,
-
-  /** Unexpected internal error, transaction should be aborted */
-  MDBX_PROBLEM = -30779,
-
-  /** The last LMDB-compatible defined error code */
-  MDBX_LAST_LMDB_ERRCODE = MDBX_PROBLEM,
-
-  /** Another write transaction is running or environment is already used while
-   * opening with \ref MDBX_EXCLUSIVE flag */
-  MDBX_BUSY = -30778,
-
-  /** The first of MDBX-added error codes */
-  MDBX_FIRST_ADDED_ERRCODE = MDBX_BUSY,
-
-  /** The specified key has more than one associated value */
-  MDBX_EMULTIVAL = -30421,
-
-  /** Bad signature of a runtime object(s), this can mean:
-   *  - memory corruption or double-free;
-   *  - ABI version mismatch (rare case); */
-  MDBX_EBADSIGN = -30420,
-
-  /** Database should be recovered, but this could NOT be done for now
-   * since it opened in read-only mode */
-  MDBX_WANNA_RECOVERY = -30419,
-
-  /** The given key value is mismatched to the current cursor position */
-  MDBX_EKEYMISMATCH = -30418,
-
-  /** Database is too large for current system,
-   * e.g. could NOT be mapped into RAM. */
-  MDBX_TOO_LARGE = -30417,
-
-  /** A thread has attempted to use a not owned object,
-   * e.g. a transaction that started by another thread. */
-  MDBX_THREAD_MISMATCH = -30416,
-
-  /** Overlapping read and write transactions for the current thread */
-  MDBX_TXN_OVERLAPPING = -30415,
-
-  /* The last of MDBX-added error codes */
-  MDBX_LAST_ADDED_ERRCODE = MDBX_TXN_OVERLAPPING,
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_ENODATA = ERROR_HANDLE_EOF,
-  MDBX_EINVAL = ERROR_INVALID_PARAMETER,
-  MDBX_EACCESS = ERROR_ACCESS_DENIED,
-  MDBX_ENOMEM = ERROR_OUTOFMEMORY,
-  MDBX_EROFS = ERROR_FILE_READ_ONLY,
-  MDBX_ENOSYS = ERROR_NOT_SUPPORTED,
-  MDBX_EIO = ERROR_WRITE_FAULT,
-  MDBX_EPERM = ERROR_INVALID_FUNCTION,
-  MDBX_EINTR = ERROR_CANCELLED,
-  MDBX_ENOFILE = ERROR_FILE_NOT_FOUND,
-  MDBX_EREMOTE = ERROR_REMOTE_STORAGE_MEDIA_ERROR
-#else /* Windows */
-#ifdef ENODATA
-  MDBX_ENODATA = ENODATA,
-#else
-  MDBX_ENODATA = -1,
-#endif /* ENODATA */
-  MDBX_EINVAL = EINVAL,
-  MDBX_EACCESS = EACCES,
-  MDBX_ENOMEM = ENOMEM,
-  MDBX_EROFS = EROFS,
-  MDBX_ENOSYS = ENOSYS,
-  MDBX_EIO = EIO,
-  MDBX_EPERM = EPERM,
-  MDBX_EINTR = EINTR,
-  MDBX_ENOFILE = ENOENT,
-  MDBX_EREMOTE = ENOTBLK
-#endif /* !Windows */
-};
-#ifndef __cplusplus
-/** \ingroup c_err */
-typedef enum MDBX_error_t MDBX_error_t;
-#endif
-
-/** MDBX_MAP_RESIZED
- * \ingroup c_err
- * \deprecated Please review your code to use MDBX_UNABLE_EXTEND_MAPSIZE
- * instead. */
-MDBX_DEPRECATED static __inline int MDBX_MAP_RESIZED_is_deprecated() {
-  return MDBX_UNABLE_EXTEND_MAPSIZE;
-}
-#define MDBX_MAP_RESIZED MDBX_MAP_RESIZED_is_deprecated()
-
-/** \brief Return a string describing a given error code.
- * \ingroup c_err
- *
- * This function is a superset of the ANSI C X3.159-1989 (ANSI C) `strerror()`
- * function. If the error code is greater than or equal to 0, then the string
- * returned by the system function `strerror()` is returned. If the error code
- * is less than 0, an error string corresponding to the MDBX library error is
- * returned. See errors for a list of MDBX-specific error codes.
- *
- * `mdbx_strerror()` is NOT thread-safe because may share common internal buffer
- * for system messages. The returned string must NOT be modified by the
- * application, but MAY be modified by a subsequent call to
- * \ref mdbx_strerror(), `strerror()` and other related functions.
- * \see mdbx_strerror_r()
- *
- * \param [in] errnum  The error code.
- *
- * \returns "error message" The description of the error. */
-LIBMDBX_API const char *mdbx_strerror(int errnum);
-
-/** \brief Return a string describing a given error code.
- * \ingroup c_err
- *
- * This function is a superset of the ANSI C X3.159-1989 (ANSI C) `strerror()`
- * function. If the error code is greater than or equal to 0, then the string
- * returned by the system function `strerror()` is returned. If the error code
- * is less than 0, an error string corresponding to the MDBX library error is
- * returned. See errors for a list of MDBX-specific error codes.
- *
- * `mdbx_strerror_r()` is thread-safe since uses user-supplied buffer where
- * appropriate. The returned string must NOT be modified by the application,
- * since it may be pointer to internal constant string. However, there is no
- * restriction if the returned string points to the supplied buffer.
- * \see mdbx_strerror()
- *
- * mdbx_liberr2str() returns string describing only MDBX error numbers but NULL
- * for non-MDBX error codes. This function is thread-safe since return pointer
- * to constant non-localized strings.
- *
- * \param [in] errnum  The error code.
- * \param [in,out] buf Buffer to store the error message.
- * \param [in] buflen The size of buffer to store the message.
- *
- * \returns "error message" The description of the error. */
-LIBMDBX_API const char *mdbx_strerror_r(int errnum, char *buf, size_t buflen);
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API const char *mdbx_liberr2str(int errnum);
-
-#if defined(_WIN32) || defined(_WIN64) || defined(DOXYGEN)
-/** Bit of Windows' madness. The similar to \ref mdbx_strerror() but returns
- * Windows error-messages in the OEM-encoding for console utilities.
- * \ingroup c_err
- * \see mdbx_strerror_r_ANSI2OEM() */
-LIBMDBX_API const char *mdbx_strerror_ANSI2OEM(int errnum);
-
-/** Bit of Windows' madness. The similar to \ref mdbx_strerror_r() but returns
- * Windows error-messages in the OEM-encoding for console utilities.
- * \ingroup c_err
- * \see mdbx_strerror_ANSI2OEM() */
-LIBMDBX_API const char *mdbx_strerror_r_ANSI2OEM(int errnum, char *buf,
-                                                 size_t buflen);
-#endif /* Bit of Windows' madness */
-
-/** \brief Create an MDBX environment instance.
- * \ingroup c_opening
- *
- * This function allocates memory for a \ref MDBX_env structure. To release
- * the allocated memory and discard the handle, call \ref mdbx_env_close().
- * Before the handle may be used, it must be opened using \ref mdbx_env_open().
- *
- * Various other options may also need to be set before opening the handle,
- * e.g. \ref mdbx_env_set_geometry(), \ref mdbx_env_set_maxreaders(),
- * \ref mdbx_env_set_maxdbs(), depending on usage requirements.
- *
- * \param [out] penv  The address where the new handle will be stored.
- *
- * \returns a non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_create(MDBX_env **penv);
-
-/** \brief MDBX environment options. */
-enum MDBX_option_t {
-  /** \brief Controls the maximum number of named databases for the environment.
-   *
-   * \details By default only unnamed key-value database could used and
-   * appropriate value should set by `MDBX_opt_max_db` to using any more named
-   * subDB(s). To reduce overhead, use the minimum sufficient value. This option
-   * may only set after \ref mdbx_env_create() and before \ref mdbx_env_open().
-   *
-   * \see mdbx_env_set_maxdbs() \see mdbx_env_get_maxdbs() */
-  MDBX_opt_max_db,
-
-  /** \brief Defines the maximum number of threads/reader slots
-   * for all processes interacting with the database.
-   *
-   * \details This defines the number of slots in the lock table that is used to
-   * track readers in the the environment. The default is about 100 for 4K
-   * system page size. Starting a read-only transaction normally ties a lock
-   * table slot to the current thread until the environment closes or the thread
-   * exits. If \ref MDBX_NOTLS is in use, \ref mdbx_txn_begin() instead ties the
-   * slot to the \ref MDBX_txn object until it or the \ref MDBX_env object is
-   * destroyed. This option may only set after \ref mdbx_env_create() and before
-   * \ref mdbx_env_open(), and has an effect only when the database is opened by
-   * the first process interacts with the database.
-   *
-   * \see mdbx_env_set_maxreaders() \see mdbx_env_get_maxreaders() */
-  MDBX_opt_max_readers,
-
-  /** \brief Controls interprocess/shared threshold to force flush the data
-   * buffers to disk, if \ref MDBX_SAFE_NOSYNC is used.
-   *
-   * \see mdbx_env_set_syncbytes() \see mdbx_env_get_syncbytes() */
-  MDBX_opt_sync_bytes,
-
-  /** \brief Controls interprocess/shared relative period since the last
-   * unsteady commit to force flush the data buffers to disk,
-   * if \ref MDBX_SAFE_NOSYNC is used.
-   * \see mdbx_env_set_syncperiod() \see mdbx_env_get_syncperiod() */
-  MDBX_opt_sync_period,
-
-  /** \brief Controls the in-process limit to grow a list of reclaimed/recycled
-   * page's numbers for finding a sequence of contiguous pages for large data
-   * items.
-   *
-   * \details A long values requires allocation of contiguous database pages.
-   * To find such sequences, it may be necessary to accumulate very large lists,
-   * especially when placing very long values (more than a megabyte) in a large
-   * databases (several tens of gigabytes), which is much expensive in extreme
-   * cases. This threshold allows you to avoid such costs by allocating new
-   * pages at the end of the database (with its possible growth on disk),
-   * instead of further accumulating/reclaiming Garbage Collection records.
-   *
-   * On the other hand, too small threshold will lead to unreasonable database
-   * growth, or/and to the inability of put long values.
-   *
-   * The `MDBX_opt_rp_augment_limit` controls described limit for the current
-   * process. Default is 262144, it is usually enough for most cases. */
-  MDBX_opt_rp_augment_limit,
-
-  /** \brief Controls the in-process limit to grow a cache of dirty
-   * pages for reuse in the current transaction.
-   *
-   * \details A 'dirty page' refers to a page that has been updated in memory
-   * only, the changes to a dirty page are not yet stored on disk.
-   * To reduce overhead, it is reasonable to release not all such pages
-   * immediately, but to leave some ones in cache for reuse in the current
-   * transaction.
-   *
-   * The `MDBX_opt_loose_limit` allows you to set a limit for such cache inside
-   * the current process. Should be in the range 0..255, default is 64. */
-  MDBX_opt_loose_limit,
-
-  /** \brief Controls the in-process limit of a pre-allocated memory items
-   * for dirty pages.
-   *
-   * \details A 'dirty page' refers to a page that has been updated in memory
-   * only, the changes to a dirty page are not yet stored on disk.
-   * Without \ref MDBX_WRITEMAP dirty pages are allocated from memory and
-   * released when a transaction is committed. To reduce overhead, it is
-   * reasonable to release not all ones, but to leave some allocations in
-   * reserve for reuse in the next transaction(s).
-   *
-   * The `MDBX_opt_dp_reserve_limit` allows you to set a limit for such reserve
-   * inside the current process. Default is 1024. */
-  MDBX_opt_dp_reserve_limit,
-
-  /** \brief Controls the in-process limit of dirty pages
-   * for a write transaction.
-   *
-   * \details A 'dirty page' refers to a page that has been updated in memory
-   * only, the changes to a dirty page are not yet stored on disk.
-   * Without \ref MDBX_WRITEMAP dirty pages are allocated from memory and will
-   * be busy until are written to disk. Therefore for a large transactions is
-   * reasonable to limit dirty pages collecting above an some threshold but
-   * spill to disk instead.
-   *
-   * The `MDBX_opt_txn_dp_limit` controls described threshold for the current
-   * process. Default is 65536, it is usually enough for most cases. */
-  MDBX_opt_txn_dp_limit,
-
-  /** \brief Controls the in-process initial allocation size for dirty pages
-   * list of a write transaction. Default is 1024. */
-  MDBX_opt_txn_dp_initial,
-
-  /** \brief Controls the in-process how maximal part of the dirty pages may be
-   * spilled when necessary.
-   *
-   * \details The `MDBX_opt_spill_max_denominator` defines the denominator for
-   * limiting from the top for part of the current dirty pages may be spilled
-   * when the free room for a new dirty pages (i.e. distance to the
-   * `MDBX_opt_txn_dp_limit` threshold) is not enough to perform requested
-   * operation.
-   * Exactly `max_pages_to_spill = dirty_pages - dirty_pages / N`,
-   * where `N` is the value set by `MDBX_opt_spill_max_denominator`.
-   *
-   * Should be in the range 0..255, where zero means no limit, i.e. all dirty
-   * pages could be spilled. Default is 8, i.e. no more than 7/8 of the current
-   * dirty pages may be spilled when reached the condition described above. */
-  MDBX_opt_spill_max_denominator,
-
-  /** \brief Controls the in-process how minimal part of the dirty pages should
-   * be spilled when necessary.
-   *
-   * \details The `MDBX_opt_spill_min_denominator` defines the denominator for
-   * limiting from the bottom for part of the current dirty pages should be
-   * spilled when the free room for a new dirty pages (i.e. distance to the
-   * `MDBX_opt_txn_dp_limit` threshold) is not enough to perform requested
-   * operation.
-   * Exactly `min_pages_to_spill = dirty_pages / N`,
-   * where `N` is the value set by `MDBX_opt_spill_min_denominator`.
-   *
-   * Should be in the range 0..255, where zero means no restriction at the
-   * bottom. Default is 8, i.e. at least the 1/8 of the current dirty pages
-   * should be spilled when reached the condition described above. */
-  MDBX_opt_spill_min_denominator,
-
-  /** \brief Controls the in-process how much of the parent transaction dirty
-   * pages will be spilled while start each child transaction.
-   *
-   * \details The `MDBX_opt_spill_parent4child_denominator` defines the
-   * denominator to determine how much of parent transaction dirty pages will be
-   * spilled explicitly while start each child transaction.
-   * Exactly `pages_to_spill = dirty_pages / N`,
-   * where `N` is the value set by `MDBX_opt_spill_parent4child_denominator`.
-   *
-   * For a stack of nested transactions each dirty page could be spilled only
-   * once, and parent's dirty pages couldn't be spilled while child
-   * transaction(s) are running. Therefore a child transaction could reach
-   * \ref MDBX_TXN_FULL when parent(s) transaction has  spilled too less (and
-   * child reach the limit of dirty pages), either when parent(s) has spilled
-   * too more (since child can't spill already spilled pages). So there is no
-   * universal golden ratio.
-   *
-   * Should be in the range 0..255, where zero means no explicit spilling will
-   * be performed during starting nested transactions.
-   * Default is 0, i.e. by default no spilling performed during starting nested
-   * transactions, that correspond historically behaviour. */
-  MDBX_opt_spill_parent4child_denominator,
-};
-#ifndef __cplusplus
-/** \ingroup c_settings */
-typedef enum MDBX_option_t MDBX_option_t;
-#endif
-
-LIBMDBX_API int mdbx_env_set_option(MDBX_env *env, const MDBX_option_t option,
-                                    const uint64_t value);
-LIBMDBX_API int mdbx_env_get_option(const MDBX_env *env,
-                                    const MDBX_option_t option,
-                                    uint64_t *value);
-
-/** \brief Open an environment instance.
- * \ingroup c_opening
- *
- * Indifferently this function will fails or not, the \ref mdbx_env_close() must
- * be called later to discard the \ref MDBX_env handle and release associated
- * resources.
- *
- * \param [in] env       An environment handle returned
- *                       by \ref mdbx_env_create()
- *
- * \param [in] pathname  The pathname for the database or the directory in which
- *                       the database files reside. In the case of directory it
- *                       must already exist and be writable.
- *
- * \param [in] flags     Special options for this environment. This parameter
- *                       must be set to 0 or by bitwise OR'ing together one
- *                       or more of the values described above in the
- *                       \ref env_flags and \ref sync_modes sections.
- *
- * Flags set by mdbx_env_set_flags() are also used:
- *  - \ref MDBX_NOSUBDIR, \ref MDBX_RDONLY, \ref MDBX_EXCLUSIVE,
- *    \ref MDBX_WRITEMAP, \ref MDBX_NOTLS, \ref MDBX_NORDAHEAD,
- *    \ref MDBX_NOMEMINIT, \ref MDBX_COALESCE, \ref MDBX_LIFORECLAIM.
- *    See \ref env_flags section.
- *
- *  - \ref MDBX_NOMETASYNC, \ref MDBX_SAFE_NOSYNC, \ref MDBX_UTTERLY_NOSYNC.
- *    See \ref sync_modes section.
- *
- * \note `MDB_NOLOCK` flag don't supported by MDBX,
- *       try use \ref MDBX_EXCLUSIVE as a replacement.
- *
- * \note MDBX don't allow to mix processes with different \ref MDBX_SAFE_NOSYNC
- *       flags on the same environment.
- *       In such case \ref MDBX_INCOMPATIBLE will be returned.
- *
- * If the database is already exist and parameters specified early by
- * \ref mdbx_env_set_geometry() are incompatible (i.e. for instance, different
- * page size) then \ref mdbx_env_open() will return \ref MDBX_INCOMPATIBLE
- * error.
- *
- * \param [in] mode   The UNIX permissions to set on created files.
- *                    Zero value means to open existing, but do not create.
- *
- * \return A non-zero error value on failure and 0 on success,
- *         some possible errors are:
- * \retval MDBX_VERSION_MISMATCH The version of the MDBX library doesn't match
- *                            the version that created the database environment.
- * \retval MDBX_INVALID       The environment file headers are corrupted.
- * \retval MDBX_ENOENT        The directory specified by the path parameter
- *                            doesn't exist.
- * \retval MDBX_EACCES        The user didn't have permission to access
- *                            the environment files.
- * \retval MDBX_EAGAIN        The environment was locked by another process.
- * \retval MDBX_BUSY          The \ref MDBX_EXCLUSIVE flag was specified and the
- *                            environment is in use by another process,
- *                            or the current process tries to open environment
- *                            more than once.
- * \retval MDBX_INCOMPATIBLE  Environment is already opened by another process,
- *                            but with different set of \ref MDBX_SAFE_NOSYNC,
- *                            \ref MDBX_UTTERLY_NOSYNC flags.
- *                            Or if the database is already exist and parameters
- *                            specified early by \ref mdbx_env_set_geometry()
- *                            are incompatible (i.e. different pagesize, etc).
- *
- * \retval MDBX_WANNA_RECOVERY The \ref MDBX_RDONLY flag was specified but
- *                             read-write access is required to rollback
- *                             inconsistent state after a system crash.
- *
- * \retval MDBX_TOO_LARGE      Database is too large for this process,
- *                             i.e. 32-bit process tries to open >4Gb database.
- */
-LIBMDBX_API int mdbx_env_open(MDBX_env *env, const char *pathname,
-                              MDBX_env_flags_t flags, mdbx_mode_t mode);
-
-/** \brief Deletion modes for \ref mdbx_env_delete().
- * \ingroup c_extra
- * \see mdbx_env_delete() */
-enum MDBX_env_delete_mode_t {
-  /** \brief Just delete the environment's files and directory if any.
-   * \note On POSIX systems, processes already working with the database will
-   * continue to work without interference until it close the environment.
-   * \note On Windows, the behavior of `MDB_ENV_JUST_DELETE` is different
-   * because the system does not support deleting files that are currently
-   * memory mapped. */
-  MDBX_ENV_JUST_DELETE = 0,
-  /** \brief Make sure that the environment is not being used by other
-   * processes, or return an error otherwise. */
-  MDBX_ENV_ENSURE_UNUSED = 1,
-  /** \brief Wait until other processes closes the environment before deletion.
-   */
-  MDBX_ENV_WAIT_FOR_UNUSED = 2,
-};
-#ifndef __cplusplus
-/** \ingroup c_extra */
-typedef enum MDBX_env_delete_mode_t MDBX_env_delete_mode_t;
-#endif
-
-/** \brief Delete the environment's files in a proper and multiprocess-safe way.
- * \ingroup c_extra
- *
- * \param [in] pathname  The pathname for the database or the directory in which
- *                       the database files reside.
- *
- * \param [in] mode      Special deletion mode for the environment. This
- *                       parameter must be set to one of the values described
- *                       above in the \ref MDBX_env_delete_mode_t section.
- *
- * \note The \ref MDBX_ENV_JUST_DELETE don't supported on Windows since system
- * unable to delete a memory-mapped files.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_RESULT_TRUE   No corresponding files or directories were found,
- *                            so no deletion was performed. */
-LIBMDBX_API int mdbx_env_delete(const char *pathname,
-                                MDBX_env_delete_mode_t mode);
-
-/** \brief Copy an MDBX environment to the specified path, with options.
- * \ingroup c_extra
- *
- * This function may be used to make a backup of an existing environment.
- * No lockfile is created, since it gets recreated at need.
- * \note This call can trigger significant file size growth if run in
- * parallel with write transactions, because it employs a read-only
- * transaction. See long-lived transactions under \ref restrictions section.
- *
- * \param [in] env    An environment handle returned by mdbx_env_create().
- *                    It must have already been opened successfully.
- * \param [in] dest   The pathname of a file in which the copy will reside.
- *                    This file must not be already exist, but parent directory
- *                    must be writable.
- * \param [in] flags  Special options for this operation. This parameter must
- *                    be set to 0 or by bitwise OR'ing together one or more
- *                    of the values described here:
- *
- *  - \ref MDBX_CP_COMPACT
- *      Perform compaction while copying: omit free pages and sequentially
- *      renumber all pages in output. This option consumes little bit more
- *      CPU for processing, but may running quickly than the default, on
- *      account skipping free pages.
- *
- *  - \ref MDBX_CP_FORCE_DYNAMIC_SIZE
- *      Force to make resizeable copy, i.e. dynamic size instead of fixed.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_copy(MDBX_env *env, const char *dest,
-                              MDBX_copy_flags_t flags);
-
-/** \brief Copy an environment to the specified file descriptor, with
- * options. \ingroup c_extra
- *
- * This function may be used to make a backup of an existing environment.
- * No lockfile is created, since it gets recreated at need.
- * \see mdbx_env_copy()
- *
- * \note This call can trigger significant file size growth if run in
- *       parallel with write transactions, because it employs a read-only
- *       transaction. See long-lived transactions under \ref restrictions
- *       section.
- *
- * \note Fails if the environment has suffered a page leak and the destination
- *       file descriptor is associated with a pipe, socket, or FIFO.
- *
- * \param [in] env     An environment handle returned by mdbx_env_create().
- *                     It must have already been opened successfully.
- * \param [in] fd      The file descriptor to write the copy to. It must have
- *                     already been opened for Write access.
- * \param [in] flags   Special options for this operation. \see mdbx_env_copy()
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_copy2fd(MDBX_env *env, mdbx_filehandle_t fd,
-                                 MDBX_copy_flags_t flags);
-
-/** \brief Statistics for a database in the environment
- * \ingroup c_statinfo
- * \see mdbx_env_stat_ex() \see mdbx_dbi_stat() */
-struct MDBX_stat {
-  uint32_t ms_psize; /**< Size of a database page. This is the same for all
-                        databases. */
-  uint32_t ms_depth; /**< Depth (height) of the B-tree */
-  uint64_t ms_branch_pages;   /**< Number of internal (non-leaf) pages */
-  uint64_t ms_leaf_pages;     /**< Number of leaf pages */
-  uint64_t ms_overflow_pages; /**< Number of overflow pages */
-  uint64_t ms_entries;        /**< Number of data items */
-  uint64_t ms_mod_txnid; /**< Transaction ID of committed last modification */
-};
-#ifndef __cplusplus
-/** \ingroup c_statinfo */
-typedef struct MDBX_stat MDBX_stat;
-#endif
-
-/** \brief Return statistics about the MDBX environment.
- * \ingroup c_statinfo
- *
- * At least one of env or txn argument must be non-null. If txn is passed
- * non-null then stat will be filled accordingly to the given transaction.
- * Otherwise, if txn is null, then stat will be populated by a snapshot from
- * the last committed write transaction, and at next time, other information
- * can be returned.
- *
- * Legacy mdbx_env_stat() correspond to calling \ref mdbx_env_stat_ex() with the
- * null `txn` argument.
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create()
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin()
- * \param [out] stat   The address of an \ref MDBX_stat structure where
- *                     the statistics will be copied
- * \param [in] bytes   The size of \ref MDBX_stat.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_stat_ex(const MDBX_env *env, const MDBX_txn *txn,
-                                 MDBX_stat *stat, size_t bytes);
-
-/** \brief Return statistics about the MDBX environment.
- * \ingroup c_statinfo
- * \deprecated Please use mdbx_env_stat_ex() instead. */
-MDBX_DEPRECATED LIBMDBX_INLINE_API(int, mdbx_env_stat,
-                                   (const MDBX_env *env, MDBX_stat *stat,
-                                    size_t bytes)) {
-  return mdbx_env_stat_ex(env, NULL, stat, bytes);
-}
-
-/** \brief Information about the environment
- * \ingroup c_statinfo
- * \see mdbx_env_info_ex() */
-struct MDBX_envinfo {
-  struct {
-    uint64_t lower;   /**< Lower limit for datafile size */
-    uint64_t upper;   /**< Upper limit for datafile size */
-    uint64_t current; /**< Current datafile size */
-    uint64_t shrink;  /**< Shrink threshold for datafile */
-    uint64_t grow;    /**< Growth step for datafile */
-  } mi_geo;
-  uint64_t mi_mapsize;             /**< Size of the data memory map */
-  uint64_t mi_last_pgno;           /**< Number of the last used page */
-  uint64_t mi_recent_txnid;        /**< ID of the last committed transaction */
-  uint64_t mi_latter_reader_txnid; /**< ID of the last reader transaction */
-  uint64_t mi_self_latter_reader_txnid; /**< ID of the last reader transaction
-                                           of caller process */
-  uint64_t mi_meta0_txnid, mi_meta0_sign;
-  uint64_t mi_meta1_txnid, mi_meta1_sign;
-  uint64_t mi_meta2_txnid, mi_meta2_sign;
-  uint32_t mi_maxreaders;   /**< Total reader slots in the environment */
-  uint32_t mi_numreaders;   /**< Max reader slots used in the environment */
-  uint32_t mi_dxb_pagesize; /**< Database pagesize */
-  uint32_t mi_sys_pagesize; /**< System pagesize */
-
-  /** \brief A mostly unique ID that is regenerated on each boot.
-
-   As such it can be used to identify the local machine's current boot. MDBX
-   uses such when open the database to determine whether rollback required to
-   the last steady sync point or not. I.e. if current bootid is differ from the
-   value within a database then the system was rebooted and all changes since
-   last steady sync must be reverted for data integrity. Zeros mean that no
-   relevant information is available from the system. */
-  struct {
-    struct {
-      uint64_t x, y;
-    } current, meta0, meta1, meta2;
-  } mi_bootid;
-
-  /** Bytes not explicitly synchronized to disk */
-  uint64_t mi_unsync_volume;
-  /** Current auto-sync threshold, see \ref mdbx_env_set_syncbytes(). */
-  uint64_t mi_autosync_threshold;
-  /** Time since the last steady sync in 1/65536 of second */
-  uint32_t mi_since_sync_seconds16dot16;
-  /** Current auto-sync period in 1/65536 of second,
-   * see \ref mdbx_env_set_syncperiod(). */
-  uint32_t mi_autosync_period_seconds16dot16;
-  /** Time since the last readers check in 1/65536 of second,
-   * see \ref mdbx_reader_check(). */
-  uint32_t mi_since_reader_check_seconds16dot16;
-  /** Current environment mode.
-   * The same as \ref mdbx_env_get_flags() returns. */
-  uint32_t mi_mode;
-};
-#ifndef __cplusplus
-/** \ingroup c_statinfo */
-typedef struct MDBX_envinfo MDBX_envinfo;
-#endif
-
-/** \brief Return information about the MDBX environment.
- * \ingroup c_statinfo
- *
- * At least one of env or txn argument must be non-null. If txn is passed
- * non-null then stat will be filled accordingly to the given transaction.
- * Otherwise, if txn is null, then stat will be populated by a snapshot from
- * the last committed write transaction, and at next time, other information
- * can be returned.
- *
- * Legacy \ref mdbx_env_info() correspond to calling \ref mdbx_env_info_ex()
- * with the null `txn` argument.
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create()
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin()
- * \param [out] info   The address of an \ref MDBX_envinfo structure
- *                     where the information will be copied
- * \param [in] bytes   The size of \ref MDBX_envinfo.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_info_ex(const MDBX_env *env, const MDBX_txn *txn,
-                                 MDBX_envinfo *info, size_t bytes);
-/** \brief Return information about the MDBX environment.
- * \ingroup c_statinfo
- * \deprecated Please use mdbx_env_info_ex() instead. */
-MDBX_DEPRECATED LIBMDBX_INLINE_API(int, mdbx_env_info,
-                                   (const MDBX_env *env, MDBX_envinfo *info,
-                                    size_t bytes)) {
-  return mdbx_env_info_ex(env, NULL, info, bytes);
-}
-
-/** \brief Flush the environment data buffers to disk.
- * \ingroup c_extra
- *
- * Unless the environment was opened with no-sync flags (\ref MDBX_NOMETASYNC,
- * \ref MDBX_SAFE_NOSYNC and \ref MDBX_UTTERLY_NOSYNC), then
- * data is always written an flushed to disk when \ref mdbx_txn_commit() is
- * called. Otherwise \ref mdbx_env_sync() may be called to manually write and
- * flush unsynced data to disk.
- *
- * Besides, \ref mdbx_env_sync_ex() with argument `force=false` may be used to
- * provide polling mode for lazy/asynchronous sync in conjunction with
- * \ref mdbx_env_set_syncbytes() and/or \ref mdbx_env_set_syncperiod().
- *
- * \note This call is not valid if the environment was opened with MDBX_RDONLY.
- *
- * \param [in] env      An environment handle returned by \ref mdbx_env_create()
- * \param [in] force    If non-zero, force a flush. Otherwise, If force is
- *                      zero, then will run in polling mode,
- *                      i.e. it will check the thresholds that were
- *                      set \ref mdbx_env_set_syncbytes()
- *                      and/or \ref mdbx_env_set_syncperiod() and perform flush
- *                      if at least one of the thresholds is reached.
- *
- * \param [in] nonblock Don't wait if write transaction
- *                      is running by other thread.
- *
- * \returns A non-zero error value on failure and \ref MDBX_RESULT_TRUE or 0 on
- *     success. The \ref MDBX_RESULT_TRUE means no data pending for flush
- *     to disk, and 0 otherwise. Some possible errors are:
- *
- * \retval MDBX_EACCES   the environment is read-only.
- * \retval MDBX_BUSY     the environment is used by other thread
- *                       and `nonblock=true`.
- * \retval MDBX_EINVAL   an invalid parameter was specified.
- * \retval MDBX_EIO      an error occurred during synchronization. */
-LIBMDBX_API int mdbx_env_sync_ex(MDBX_env *env, bool force, bool nonblock);
-
-/** \brief The shortcut to calling \ref mdbx_env_sync_ex() with
- * the `force=true` and `nonblock=false` arguments.
- * \ingroup c_extra */
-LIBMDBX_INLINE_API(int, mdbx_env_sync, (MDBX_env * env)) {
-  return mdbx_env_sync_ex(env, true, false);
-}
-
-/** \brief The shortcut to calling \ref mdbx_env_sync_ex() with
- * the `force=false` and `nonblock=true` arguments.
- * \ingroup c_extra */
-LIBMDBX_INLINE_API(int, mdbx_env_sync_poll, (MDBX_env * env)) {
-  return mdbx_env_sync_ex(env, false, true);
-}
-
-/** \brief Sets threshold to force flush the data buffers to disk, even any of
- * \ref MDBX_SAFE_NOSYNC flag in the environment.
- * \ingroup c_settings
- *
- * The threshold value affects all processes which operates with given
- * environment until the last process close environment or a new value will be
- * settled.
- *
- * Data is always written to disk when \ref mdbx_txn_commit() is called, but
- * the operating system may keep it buffered. MDBX always flushes the OS buffers
- * upon commit as well, unless the environment was opened with
- * \ref MDBX_SAFE_NOSYNC, \ref MDBX_UTTERLY_NOSYNC
- * or in part \ref MDBX_NOMETASYNC.
- *
- * The default is 0, than mean no any threshold checked, and no additional
- * flush will be made.
- *
- * \param [in] env         An environment handle returned by mdbx_env_create().
- * \param [in] threshold   The size in bytes of summary changes when
- *                         a synchronous flush would be made.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_INLINE_API(int, mdbx_env_set_syncbytes,
-                   (MDBX_env * env, size_t threshold)) {
-  return mdbx_env_set_option(env, MDBX_opt_sync_bytes, threshold);
-}
-
-/** \brief Sets relative period since the last unsteady commit to force flush
- * the data buffers to disk, even of \ref MDBX_SAFE_NOSYNC flag in the
- * environment.
- *
- * \ingroup c_settings
- *
- * The relative period value affects all processes which operates with given
- * environment until the last process close environment or a new value will be
- * settled.
- *
- * Data is always written to disk when \ref mdbx_txn_commit() is called, but the
- * operating system may keep it buffered. MDBX always flushes the OS buffers
- * upon commit as well, unless the environment was opened with
- * \ref MDBX_SAFE_NOSYNC or in part \ref MDBX_NOMETASYNC.
- *
- * Settled period don't checked asynchronously, but only by the
- * \ref mdbx_txn_commit() and \ref mdbx_env_sync() functions. Therefore, in
- * cases where transactions are committed infrequently and/or irregularly,
- * polling by \ref mdbx_env_sync() may be a reasonable solution to timeout
- * enforcement.
- *
- * The default is 0, than mean no any timeout checked, and no additional
- * flush will be made.
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- * \param [in] seconds_16dot16  The period in 1/65536 of second when
- *                              a synchronous flush would be made since
- *                              the last unsteady commit.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_INLINE_API(int, mdbx_env_set_syncperiod,
-                   (MDBX_env * env, unsigned seconds_16dot16)) {
-  return mdbx_env_set_option(env, MDBX_opt_sync_period, seconds_16dot16);
-}
-
-/** \brief Close the environment and release the memory map.
- * \ingroup c_opening
- *
- * Only a single thread may call this function. All transactions, databases,
- * and cursors must already be closed before calling this function. Attempts
- * to use any such handles after calling this function will cause a `SIGSEGV`.
- * The environment handle will be freed and must not be used again after this
- * call.
- *
- * \param [in] env        An environment handle returned by
- *                        \ref mdbx_env_create().
- *
- * \param [in] dont_sync  A dont'sync flag, if non-zero the last checkpoint
- *                        will be kept "as is" and may be still "weak" in the
- *                        \ref MDBX_SAFE_NOSYNC or \ref MDBX_UTTERLY_NOSYNC
- *                        modes. Such "weak" checkpoint will be ignored on
- *                        opening next time, and transactions since the last
- *                        non-weak checkpoint (meta-page update) will rolledback
- *                        for consistency guarantee.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_BUSY   The write transaction is running by other thread,
- *                     in such case \ref MDBX_env instance has NOT be destroyed
- *                     not released!
- *                     \note If any OTHER error code was returned then
- *                     given MDBX_env instance has been destroyed and released.
- *
- * \retval MDBX_EBADSIGN  Environment handle already closed or not valid,
- *                        i.e. \ref mdbx_env_close() was already called for the
- *                        `env` or was not created by \ref mdbx_env_create().
- *
- * \retval MDBX_PANIC  If \ref mdbx_env_close_ex() was called in the child
- *                     process after `fork()`. In this case \ref MDBX_PANIC
- *                     is expected, i.e. \ref MDBX_env instance was freed in
- *                     proper manner.
- *
- * \retval MDBX_EIO    An error occurred during synchronization. */
-LIBMDBX_API int mdbx_env_close_ex(MDBX_env *env, bool dont_sync);
-
-/** \brief The shortcut to calling \ref mdbx_env_close_ex() with
- * the `dont_sync=false` argument.
- * \ingroup c_opening */
-LIBMDBX_INLINE_API(int, mdbx_env_close, (MDBX_env * env)) {
-  return mdbx_env_close_ex(env, false);
-}
-
-/** \brief Set environment flags.
- * \ingroup c_settings
- *
- * This may be used to set some flags in addition to those from
- * mdbx_env_open(), or to unset these flags.
- * \see mdbx_env_get_flags()
- *
- * \note In contrast to LMDB, the MDBX serialize threads via mutex while
- * changing the flags. Therefore this function will be blocked while a write
- * transaction running by other thread, or \ref MDBX_BUSY will be returned if
- * function called within a write transaction.
- *
- * \param [in] env      An environment handle returned
- *                      by \ref mdbx_env_create().
- * \param [in] flags    The \ref env_flags to change, bitwise OR'ed together.
- * \param [in] onoff    A non-zero value sets the flags, zero clears them.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL  An invalid parameter was specified. */
-LIBMDBX_API int mdbx_env_set_flags(MDBX_env *env, MDBX_env_flags_t flags,
-                                   bool onoff);
-
-/** \brief Get environment flags.
- * \ingroup c_statinfo
- * \see mdbx_env_set_flags()
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create().
- * \param [out] flags  The address of an integer to store the flags.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL An invalid parameter was specified. */
-LIBMDBX_API int mdbx_env_get_flags(const MDBX_env *env, unsigned *flags);
-
-/** \brief Return the path that was used in mdbx_env_open().
- * \ingroup c_statinfo
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create()
- * \param [out] dest   Address of a string pointer to contain the path.
- *                     This is the actual string in the environment, not a
- *                     copy. It should not be altered in any way.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL  An invalid parameter was specified. */
-LIBMDBX_API int mdbx_env_get_path(const MDBX_env *env, const char **dest);
-
-/** \brief Return the file descriptor for the given environment.
- * \ingroup c_statinfo
- *
- * \note All MDBX file descriptors have `FD_CLOEXEC` and
- *       couldn't be used after exec() and or `fork()`.
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- * \param [out] fd   Address of a int to contain the descriptor.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL  An invalid parameter was specified. */
-LIBMDBX_API int mdbx_env_get_fd(const MDBX_env *env, mdbx_filehandle_t *fd);
-
-/** \brief Set all size-related parameters of environment, including page size
- * and the min/max size of the memory map. \ingroup c_settings
- *
- * In contrast to LMDB, the MDBX provide automatic size management of an
- * database according the given parameters, including shrinking and resizing
- * on the fly. From user point of view all of these just working. Nevertheless,
- * it is reasonable to know some details in order to make optimal decisions
- * when choosing parameters.
- *
- * Both \ref mdbx_env_info_ex() and legacy \ref mdbx_env_info() are inapplicable
- * to read-only opened environment.
- *
- * Both \ref mdbx_env_info_ex() and legacy \ref mdbx_env_info() could be called
- * either before or after \ref mdbx_env_open(), either within the write
- * transaction running by current thread or not:
- *
- *  - In case \ref mdbx_env_info_ex() or legacy \ref mdbx_env_info() was called
- *    BEFORE \ref mdbx_env_open(), i.e. for closed environment, then the
- *    specified parameters will be used for new database creation, or will be
- *    applied during opening if database exists and no other process using it.
- *
- *    If the database is already exist, opened with \ref MDBX_EXCLUSIVE or not
- *    used by any other process, and parameters specified by
- *    \ref mdbx_env_set_geometry() are incompatible (i.e. for instance,
- *    different page size) then \ref mdbx_env_open() will return
- *    \ref MDBX_INCOMPATIBLE error.
- *
- *    In another way, if database will opened read-only or will used by other
- *    process during calling \ref mdbx_env_open() that specified parameters will
- *    silently discarded (open the database with \ref MDBX_EXCLUSIVE flag
- *    to avoid this).
- *
- *  - In case \ref mdbx_env_info_ex() or legacy \ref mdbx_env_info() was called
- *    after \ref mdbx_env_open() WITHIN the write transaction running by current
- *    thread, then specified parameters will be applied as a part of write
- *    transaction, i.e. will not be visible to any others processes until the
- *    current write transaction has been committed by the current process.
- *    However, if transaction will be aborted, then the database file will be
- *    reverted to the previous size not immediately, but when a next transaction
- *    will be committed or when the database will be opened next time.
- *
- *  - In case \ref mdbx_env_info_ex() or legacy \ref mdbx_env_info() was called
- *    after \ref mdbx_env_open() but OUTSIDE a write transaction, then MDBX will
- *    execute internal pseudo-transaction to apply new parameters (but only if
- *    anything has been changed), and changes be visible to any others processes
- *    immediately after succesful completion of function.
- *
- * Essentially a concept of "automatic size management" is simple and useful:
- *  - There are the lower and upper bound of the database file size;
- *  - There is the growth step by which the database file will be increased,
- *    in case of lack of space.
- *  - There is the threshold for unused space, beyond which the database file
- *    will be shrunk.
- *  - The size of the memory map is also the maximum size of the database.
- *  - MDBX will automatically manage both the size of the database and the size
- *    of memory map, according to the given parameters.
- *
- * So, there some considerations about choosing these parameters:
- *  - The lower bound allows you to prevent database shrinking below some
- *    rational size to avoid unnecessary resizing costs.
- *  - The upper bound allows you to prevent database growth above some rational
- *    size. Besides, the upper bound defines the linear address space
- *    reservation in each process that opens the database. Therefore changing
- *    the upper bound is costly and may be required reopening environment in
- *    case of \ref MDBX_UNABLE_EXTEND_MAPSIZE errors, and so on. Therefore, this
- *    value should be chosen reasonable as large as possible, to accommodate
- *    future growth of the database.
- *  - The growth step must be greater than zero to allow the database to grow,
- *    but also reasonable not too small, since increasing the size by little
- *    steps will result a large overhead.
- *  - The shrink threshold must be greater than zero to allow the database
- *    to shrink but also reasonable not too small (to avoid extra overhead) and
- *    not less than growth step to avoid up-and-down flouncing.
- *  - The current size (i.e. size_now argument) is an auxiliary parameter for
- *    simulation legacy \ref mdbx_env_set_mapsize() and as workaround Windows
- *    issues (see below).
- *
- * Unfortunately, Windows has is a several issues
- * with resizing of memory-mapped file:
- *  - Windows unable shrinking a memory-mapped file (i.e memory-mapped section)
- *    in any way except unmapping file entirely and then map again. Moreover,
- *    it is impossible in any way if a memory-mapped file is used more than
- *    one process.
- *  - Windows does not provide the usual API to augment a memory-mapped file
- *    (that is, a memory-mapped partition), but only by using "Native API"
- *    in an undocumented way.
- *
- * MDBX bypasses all Windows issues, but at a cost:
- *  - Ability to resize database on the fly requires an additional lock
- *    and release `SlimReadWriteLock during` each read-only transaction.
- *  - During resize all in-process threads should be paused and then resumed.
- *  - Shrinking of database file is performed only when it used by single
- *    process, i.e. when a database closes by the last process or opened
- *    by the first.
- *  = Therefore, the size_now argument may be useful to set database size
- *    by the first process which open a database, and thus avoid expensive
- *    remapping further.
- *
- * For create a new database with particular parameters, including the page
- * size, \ref mdbx_env_set_geometry() should be called after
- * \ref mdbx_env_create() and before mdbx_env_open(). Once the database is
- * created, the page size cannot be changed. If you do not specify all or some
- * of the parameters, the corresponding default values will be used. For
- * instance, the default for database size is 10485760 bytes.
- *
- * If the mapsize is increased by another process, MDBX silently and
- * transparently adopt these changes at next transaction start. However,
- * \ref mdbx_txn_begin() will return \ref MDBX_UNABLE_EXTEND_MAPSIZE if new
- * mapping size could not be applied for current process (for instance if
- * address space is busy).  Therefore, in the case of
- * \ref MDBX_UNABLE_EXTEND_MAPSIZE error you need close and reopen the
- * environment to resolve error.
- *
- * \note Actual values may be different than your have specified because of
- * rounding to specified database page size, the system page size and/or the
- * size of the system virtual memory management unit. You can get actual values
- * by \ref mdbx_env_sync_ex() or see by using the tool `mdbx_chk` with the `-v`
- * option.
- *
- * Legacy \ref mdbx_env_set_mapsize() correspond to calling
- * \ref mdbx_env_set_geometry() with the arguments `size_lower`, `size_now`,
- * `size_upper` equal to the `size` and `-1` (i.e. default) for all other
- * parameters.
- *
- * \param [in] env         An environment handle returned
- *                         by \ref mdbx_env_create()
- *
- * \param [in] size_lower  The lower bound of database size in bytes.
- *                         Zero value means "minimal acceptable",
- *                         and negative means "keep current or use default".
- *
- * \param [in] size_now    The size in bytes to setup the database size for
- *                         now. Zero value means "minimal acceptable", and
- *                         negative means "keep current or use default". So,
- *                         it is recommended always pass -1 in this argument
- *                         except some special cases.
- *
- * \param [in] size_upper The upper bound of database size in bytes.
- *                        Zero value means "minimal acceptable",
- *                        and negative means "keep current or use default".
- *                        It is recommended to avoid change upper bound while
- *                        database is used by other processes or threaded
- *                        (i.e. just pass -1 in this argument except absolutely
- *                        necessary). Otherwise you must be ready for
- *                        \ref MDBX_UNABLE_EXTEND_MAPSIZE error(s), unexpected
- *                        pauses during remapping and/or system errors like
- *                        "address busy", and so on. In other words, there
- *                        is no way to handle a growth of the upper bound
- *                        robustly because there may be a lack of appropriate
- *                        system resources (which are extremely volatile in
- *                        a multi-process multi-threaded environment).
- *
- * \param [in] growth_step  The growth step in bytes, must be greater than
- *                          zero to allow the database to grow. Negative value
- *                          means "keep current or use default".
- *
- * \param [in] shrink_threshold  The shrink threshold in bytes, must be greater
- *                               than zero to allow the database to shrink and
- *                               greater than growth_step to avoid shrinking
- *                               right after grow.
- *                               Negative value means "keep current
- *                               or use default". Default is 2*growth_step.
- *
- * \param [in] pagesize          The database page size for new database
- *                               creation or -1 otherwise. Must be power of 2
- *                               in the range between \ref MDBX_MIN_PAGESIZE and
- *                               \ref MDBX_MAX_PAGESIZE. Zero value means
- *                               "minimal acceptable", and negative means
- *                               "keep current or use default".
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL    An invalid parameter was specified,
- *                        or the environment has an active write transaction.
- * \retval MDBX_EPERM     Specific for Windows: Shrinking was disabled before
- *                        and now it wanna be enabled, but there are reading
- *                        threads that don't use the additional `SRWL` (that
- *                        is required to avoid Windows issues).
- * \retval MDBX_EACCESS   The environment opened in read-only.
- * \retval MDBX_MAP_FULL  Specified size smaller than the space already
- *                        consumed by the environment.
- * \retval MDBX_TOO_LARGE Specified size is too large, i.e. too many pages for
- *                        given size, or a 32-bit process requests too much
- *                        bytes for the 32-bit address space. */
-LIBMDBX_API int mdbx_env_set_geometry(MDBX_env *env, intptr_t size_lower,
-                                      intptr_t size_now, intptr_t size_upper,
-                                      intptr_t growth_step,
-                                      intptr_t shrink_threshold,
-                                      intptr_t pagesize);
-
-/** \deprecated Please use \ref mdbx_env_set_geometry() instead.
- * \ingroup c_settings */
-MDBX_DEPRECATED LIBMDBX_INLINE_API(int, mdbx_env_set_mapsize,
-                                   (MDBX_env * env, size_t size)) {
-  return mdbx_env_set_geometry(env, size, size, size, -1, -1, -1);
-}
-
-/** \brief Find out whether to use readahead or not, based on the given database
- * size and the amount of available memory. \ingroup c_extra
- *
- * \param [in] volume      The expected database size in bytes.
- * \param [in] redundancy  Additional reserve or overload in case of negative
- *                         value.
- *
- * \returns A \ref MDBX_RESULT_TRUE or \ref MDBX_RESULT_FALSE value,
- *          otherwise the error code:
- * \retval MDBX_RESULT_TRUE   Readahead is reasonable.
- * \retval MDBX_RESULT_FALSE  Readahead is NOT reasonable,
- *                            i.e. \ref MDBX_NORDAHEAD is useful to
- *                            open environment by \ref mdbx_env_open().
- * \retval Otherwise the error code. */
-LIBMDBX_API int mdbx_is_readahead_reasonable(size_t volume,
-                                             intptr_t redundancy);
-
-/** \brief Returns the minimal database page size in bytes.
- * \ingroup c_statinfo */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_INLINE_API(intptr_t, mdbx_limits_pgsize_min,
-                                               (void)) {
-  return MDBX_MIN_PAGESIZE;
-}
-
-/** \brief Returns the maximal database page size in bytes.
- * \ingroup c_statinfo */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_INLINE_API(intptr_t, mdbx_limits_pgsize_max,
-                                               (void)) {
-  return MDBX_MAX_PAGESIZE;
-}
-
-/** \brief Returns minimal database size in bytes for given page size,
- * or -1 if pagesize is invalid.
- * \ingroup c_statinfo */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
-mdbx_limits_dbsize_min(intptr_t pagesize);
-
-/** \brief Returns maximal database size in bytes for given page size,
- * or -1 if pagesize is invalid.
- * \ingroup c_statinfo */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
-mdbx_limits_dbsize_max(intptr_t pagesize);
-
-/** \brief Returns maximal key size in bytes for given page size
- * and database flags, or -1 if pagesize is invalid.
- * \ingroup c_statinfo
- * \see db_flags */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
-mdbx_limits_keysize_max(intptr_t pagesize, MDBX_db_flags_t flags);
-
-/** \brief Returns maximal data size in bytes for given page size
- * and database flags, or -1 if pagesize is invalid.
- * \ingroup c_statinfo
- * \see db_flags */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
-mdbx_limits_valsize_max(intptr_t pagesize, MDBX_db_flags_t flags);
-
-/** \brief Returns maximal write transaction size (i.e. limit for summary volume
- * of dirty pages) in bytes for given page size, or -1 if pagesize is invalid.
- * \ingroup c_statinfo */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API intptr_t
-mdbx_limits_txnsize_max(intptr_t pagesize);
-
-/** \brief Set the maximum number of threads/reader slots for for all processes
- * interacts with the database. \ingroup c_settings
- *
- * \details This defines the number of slots in the lock table that is used to
- * track readers in the the environment. The default is about 100 for 4K system
- * page size. Starting a read-only transaction normally ties a lock table slot
- * to the current thread until the environment closes or the thread exits. If
- * \ref MDBX_NOTLS is in use, \ref mdbx_txn_begin() instead ties the slot to the
- * \ref MDBX_txn object until it or the \ref MDBX_env object is destroyed.
- * This function may only be called after \ref mdbx_env_create() and before
- * \ref mdbx_env_open(), and has an effect only when the database is opened by
- * the first process interacts with the database.
- * \see mdbx_env_get_maxreaders()
- *
- * \param [in] env       An environment handle returned
- *                       by \ref mdbx_env_create().
- * \param [in] readers   The maximum number of reader lock table slots.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL   An invalid parameter was specified.
- * \retval MDBX_EPERM    The environment is already open. */
-LIBMDBX_INLINE_API(int, mdbx_env_set_maxreaders,
-                   (MDBX_env * env, unsigned readers)) {
-  return mdbx_env_set_option(env, MDBX_opt_max_readers, readers);
-}
-
-/** \brief Get the maximum number of threads/reader slots for the environment.
- * \ingroup c_statinfo
- * \see mdbx_env_set_maxreaders()
- *
- * \param [in] env       An environment handle returned
- *                       by \ref mdbx_env_create().
- * \param [out] readers  Address of an integer to store the number of readers.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL   An invalid parameter was specified. */
-LIBMDBX_INLINE_API(int, mdbx_env_get_maxreaders,
-                   (const MDBX_env *env, unsigned *readers)) {
-  int rc = MDBX_EINVAL;
-  if (readers) {
-    uint64_t proxy = 0;
-    rc = mdbx_env_get_option(env, MDBX_opt_max_readers, &proxy);
-    *readers = (unsigned)proxy;
-  }
-  return rc;
-}
-
-/** \brief Set the maximum number of named databases for the environment.
- * \ingroup c_settings
- *
- * This function is only needed if multiple databases will be used in the
- * environment. Simpler applications that use the environment as a single
- * unnamed database can ignore this option.
- * This function may only be called after \ref mdbx_env_create() and before
- * \ref mdbx_env_open().
- *
- * Currently a moderate number of slots are cheap but a huge number gets
- * expensive: 7-120 words per transaction, and every \ref mdbx_dbi_open()
- * does a linear search of the opened slots.
- * \see mdbx_env_get_maxdbs()
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- * \param [in] dbs   The maximum number of databases.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL   An invalid parameter was specified.
- * \retval MDBX_EPERM    The environment is already open. */
-LIBMDBX_INLINE_API(int, mdbx_env_set_maxdbs, (MDBX_env * env, MDBX_dbi dbs)) {
-  return mdbx_env_set_option(env, MDBX_opt_max_db, dbs);
-}
-
-/** \brief Get the maximum number of named databases for the environment.
- * \ingroup c_statinfo
- * \see mdbx_env_set_maxdbs()
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- * \param [out] dbs  Address to store the maximum number of databases.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EINVAL   An invalid parameter was specified. */
-LIBMDBX_INLINE_API(int, mdbx_env_get_maxdbs,
-                   (const MDBX_env *env, MDBX_dbi *dbs)) {
-  int rc = MDBX_EINVAL;
-  if (dbs) {
-    uint64_t proxy = 0;
-    rc = mdbx_env_get_option(env, MDBX_opt_max_db, &proxy);
-    *dbs = (MDBX_dbi)proxy;
-  }
-  return rc;
-}
-
-/** \brief Returns the default size of database page for the current system.
- * \ingroup c_statinfo
- * \details Default size of database page depends on the size of the system
- * page and usually exactly match it. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API size_t mdbx_default_pagesize(void);
-
-/** \brief Get the maximum size of keys can write.
- * \ingroup c_statinfo
- *
- * \param [in] env    An environment handle returned by \ref mdbx_env_create().
- * \param [in] flags  Database options (\ref MDBX_DUPSORT, \ref MDBX_INTEGERKEY
- *                    and so on). \see db_flags
- *
- * \returns The maximum size of a key can write,
- *          or -1 if something is wrong. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
-mdbx_env_get_maxkeysize_ex(const MDBX_env *env, MDBX_db_flags_t flags);
-
-/** \brief Get the maximum size of data we can write.
- * \ingroup c_statinfo
- *
- * \param [in] env    An environment handle returned by \ref mdbx_env_create().
- * \param [in] flags  Database options (\ref MDBX_DUPSORT, \ref MDBX_INTEGERKEY
- *                    and so on). \see db_flags
- *
- * \returns The maximum size of a data can write,
- *          or -1 if something is wrong. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
-mdbx_env_get_maxvalsize_ex(const MDBX_env *env, MDBX_db_flags_t flags);
-
-/** \deprecated Please use \ref mdbx_env_get_maxkeysize_ex()
- *              and/or \ref mdbx_env_get_maxvalsize_ex()
- * \ingroup c_statinfo */
-MDBX_NOTHROW_PURE_FUNCTION MDBX_DEPRECATED LIBMDBX_API int
-mdbx_env_get_maxkeysize(const MDBX_env *env);
-
-/** \brief Set application information associated with the \ref MDBX_env.
- * \ingroup c_settings
- * \see mdbx_env_get_userctx()
- *
- * \param [in] env  An environment handle returned by \ref mdbx_env_create().
- * \param [in] ctx  An arbitrary pointer for whatever the application needs.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_set_userctx(MDBX_env *env, void *ctx);
-
-/** \brief Get the application information associated with the MDBX_env.
- * \ingroup c_statinfo
- * \see mdbx_env_set_userctx()
- *
- * \param [in] env An environment handle returned by \ref mdbx_env_create()
- * \returns The pointer set by \ref mdbx_env_set_userctx()
- *          or `NULL` if something wrong. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API void *
-mdbx_env_get_userctx(const MDBX_env *env);
-
-/** \brief Create a transaction with a user provided context pointer
- * for use with the environment.
- * \ingroup c_transactions
- *
- * The transaction handle may be discarded using \ref mdbx_txn_abort()
- * or \ref mdbx_txn_commit().
- * \see mdbx_txn_begin()
- *
- * \note A transaction and its cursors must only be used by a single thread,
- * and a thread may only have a single transaction at a time. If \ref MDBX_NOTLS
- * is in use, this does not apply to read-only transactions.
- *
- * \note Cursors may not span transactions.
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create().
- *
- * \param [in] parent  If this parameter is non-NULL, the new transaction will
- *                     be a nested transaction, with the transaction indicated
- *                     by parent as its parent. Transactions may be nested
- *                     to any level. A parent transaction and its cursors may
- *                     not issue any other operations than mdbx_txn_commit and
- *                     \ref mdbx_txn_abort() while it has active child
- *                     transactions.
- *
- * \param [in] flags   Special options for this transaction. This parameter
- *                     must be set to 0 or by bitwise OR'ing together one
- *                     or more of the values described here:
- *                      - \ref MDBX_RDONLY   This transaction will not perform
- *                                           any write operations.
- *
- *                      - \ref MDBX_TXN_TRY  Do not block when starting
- *                                           a write transaction.
- *
- *                      - \ref MDBX_SAFE_NOSYNC, \ref MDBX_NOMETASYNC.
- *                        Do not sync data to disk corresponding
- *                        to \ref MDBX_NOMETASYNC or \ref MDBX_SAFE_NOSYNC
- *                        description. \see sync_modes
- *
- * \param [out] txn    Address where the new MDBX_txn handle will be stored.
- *
- * \param [in] context A pointer to application context to be associated with
- *                     created transaction and could be retrieved by
- *                     \ref mdbx_txn_get_userctx() until transaction finished.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_PANIC         A fatal error occurred earlier and the
- *                            environment must be shut down.
- * \retval MDBX_UNABLE_EXTEND_MAPSIZE  Another process wrote data beyond
- *                                     this MDBX_env's mapsize and this
- *                                     environment map must be resized as well.
- *                                     See \ref mdbx_env_set_mapsize().
- * \retval MDBX_READERS_FULL  A read-only transaction was requested and
- *                            the reader lock table is full.
- *                            See \ref mdbx_env_set_maxreaders().
- * \retval MDBX_ENOMEM        Out of memory.
- * \retval MDBX_BUSY          The write transaction is already started by the
- *                            current thread. */
-LIBMDBX_API int mdbx_txn_begin_ex(MDBX_env *env, MDBX_txn *parent,
-                                  MDBX_txn_flags_t flags, MDBX_txn **txn,
-                                  void *context);
-
-/** \brief Create a transaction for use with the environment.
- * \ingroup c_transactions
- *
- * The transaction handle may be discarded using \ref mdbx_txn_abort()
- * or \ref mdbx_txn_commit().
- * \see mdbx_txn_begin_ex()
- *
- * \note A transaction and its cursors must only be used by a single thread,
- * and a thread may only have a single transaction at a time. If \ref MDBX_NOTLS
- * is in use, this does not apply to read-only transactions.
- *
- * \note Cursors may not span transactions.
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create().
- *
- * \param [in] parent  If this parameter is non-NULL, the new transaction will
- *                     be a nested transaction, with the transaction indicated
- *                     by parent as its parent. Transactions may be nested
- *                     to any level. A parent transaction and its cursors may
- *                     not issue any other operations than mdbx_txn_commit and
- *                     \ref mdbx_txn_abort() while it has active child
- *                     transactions.
- *
- * \param [in] flags   Special options for this transaction. This parameter
- *                     must be set to 0 or by bitwise OR'ing together one
- *                     or more of the values described here:
- *                      - \ref MDBX_RDONLY   This transaction will not perform
- *                                           any write operations.
- *
- *                      - \ref MDBX_TXN_TRY  Do not block when starting
- *                                           a write transaction.
- *
- *                      - \ref MDBX_SAFE_NOSYNC, \ref MDBX_NOMETASYNC.
- *                        Do not sync data to disk corresponding
- *                        to \ref MDBX_NOMETASYNC or \ref MDBX_SAFE_NOSYNC
- *                        description. \see sync_modes
- *
- * \param [out] txn    Address where the new MDBX_txn handle will be stored.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_PANIC         A fatal error occurred earlier and the
- *                            environment must be shut down.
- * \retval MDBX_UNABLE_EXTEND_MAPSIZE  Another process wrote data beyond
- *                                     this MDBX_env's mapsize and this
- *                                     environment map must be resized as well.
- *                                     See \ref mdbx_env_set_mapsize().
- * \retval MDBX_READERS_FULL  A read-only transaction was requested and
- *                            the reader lock table is full.
- *                            See \ref mdbx_env_set_maxreaders().
- * \retval MDBX_ENOMEM        Out of memory.
- * \retval MDBX_BUSY          The write transaction is already started by the
- *                            current thread. */
-LIBMDBX_INLINE_API(int, mdbx_txn_begin,
-                   (MDBX_env * env, MDBX_txn *parent, MDBX_txn_flags_t flags,
-                    MDBX_txn **txn)) {
-  return mdbx_txn_begin_ex(env, parent, flags, txn, NULL);
-}
-
-/** \brief Set application information associated with the \ref MDBX_txn.
- * \ingroup c_transactions
- * \see mdbx_txn_get_userctx()
- *
- * \param [in] txn  An transaction handle returned by \ref mdbx_txn_begin_ex()
- *                  or \ref mdbx_txn_begin().
- * \param [in] ctx  An arbitrary pointer for whatever the application needs.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_txn_set_userctx(MDBX_txn *txn, void *ctx);
-
-/** \brief Get the application information associated with the MDBX_txn.
- * \ingroup c_transactions
- * \see mdbx_txn_set_userctx()
- *
- * \param [in] txn  An transaction handle returned by \ref mdbx_txn_begin_ex()
- *                  or \ref mdbx_txn_begin().
- * \returns The pointer which was passed via the `context` parameter
- *          of `mdbx_txn_begin_ex()` or set by \ref mdbx_txn_set_userctx(),
- *          or `NULL` if something wrong. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API void *
-mdbx_txn_get_userctx(const MDBX_txn *txn);
-
-/** \brief Information about the transaction
- * \ingroup c_statinfo
- * \see mdbx_txn_info */
-struct MDBX_txn_info {
-  /** The ID of the transaction. For a READ-ONLY transaction, this corresponds
-      to the snapshot being read. */
-  uint64_t txn_id;
-
-  /** For READ-ONLY transaction: the lag from a recent MVCC-snapshot, i.e. the
-     number of committed transaction since read transaction started.
-     For WRITE transaction (provided if `scan_rlt=true`): the lag of the oldest
-     reader from current transaction (i.e. at least 1 if any reader running). */
-  uint64_t txn_reader_lag;
-
-  /** Used space by this transaction, i.e. corresponding to the last used
-   * database page. */
-  uint64_t txn_space_used;
-
-  /** Current size of database file. */
-  uint64_t txn_space_limit_soft;
-
-  /** Upper bound for size the database file, i.e. the value `size_upper`
-     argument of the appropriate call of \ref mdbx_env_set_geometry(). */
-  uint64_t txn_space_limit_hard;
-
-  /** For READ-ONLY transaction: The total size of the database pages that were
-     retired by committed write transactions after the reader's MVCC-snapshot,
-     i.e. the space which would be freed after the Reader releases the
-     MVCC-snapshot for reuse by completion read transaction.
-     For WRITE transaction: The summarized size of the database pages that were
-     retired for now due Copy-On-Write during this transaction. */
-  uint64_t txn_space_retired;
-
-  /** For READ-ONLY transaction: the space available for writer(s) and that
-     must be exhausted for reason to call the Handle-Slow-Readers callback for
-     this read transaction.
-     For WRITE transaction: the space inside transaction
-     that left to `MDBX_TXN_FULL` error. */
-  uint64_t txn_space_leftover;
-
-  /** For READ-ONLY transaction (provided if `scan_rlt=true`): The space that
-     actually become available for reuse when only this transaction will be
-     finished.
-     For WRITE transaction: The summarized size of the dirty database
-     pages that generated during this transaction. */
-  uint64_t txn_space_dirty;
-};
-#ifndef __cplusplus
-/** \ingroup c_statinfo */
-typedef struct MDBX_txn_info MDBX_txn_info;
-#endif
-
-/** \brief Return information about the MDBX transaction.
- * \ingroup c_statinfo
- *
- * \param [in] txn        A transaction handle returned by \ref mdbx_txn_begin()
- * \param [out] info      The address of an \ref MDBX_txn_info structure
- *                        where the information will be copied.
- * \param [in] scan_rlt   The boolean flag controls the scan of the read lock
- *                        table to provide complete information. Such scan
- *                        is relatively expensive and you can avoid it
- *                        if corresponding fields are not needed.
- *                        See description of \ref MDBX_txn_info.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_txn_info(const MDBX_txn *txn, MDBX_txn_info *info,
-                              bool scan_rlt);
-
-/** \brief Returns the transaction's MDBX_env.
- * \ingroup c_transactions
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin() */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API MDBX_env *
-mdbx_txn_env(const MDBX_txn *txn);
-
-/** \brief Return the transaction's flags.
- * \ingroup c_transactions
- *
- * This returns the flags associated with this transaction.
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \returns A transaction flags, valid if input is an valid transaction,
- *          otherwise -1. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int mdbx_txn_flags(const MDBX_txn *txn);
-
-/** \brief Return the transaction's ID.
- * \ingroup c_statinfo
- *
- * This returns the identifier associated with this transaction. For a
- * read-only transaction, this corresponds to the snapshot being read;
- * concurrent readers will frequently have the same transaction ID.
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \returns A transaction ID, valid if input is an active transaction,
- *          otherwise 0. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API uint64_t
-mdbx_txn_id(const MDBX_txn *txn);
-
-/** \brief Latency of commit stages in 1/65536 of seconds units.
- * \warning This structure may be changed in future releases.
- * \see mdbx_txn_commit_ex() */
-struct MDBX_commit_latency {
-  /** \brief Duration of preparation (commit child transactions, update
-   * sub-databases records and cursors destroying). */
-  uint32_t preparation;
-  /** \brief Duration of GC/freeDB handling & updation. */
-  uint32_t gc;
-  /** \brief Duration of internal audit if enabled. */
-  uint32_t audit;
-  /** \brief Duration of writing dirty/modified data pages. */
-  uint32_t write;
-  /** \brief Duration of syncing written data to the dist/storage. */
-  uint32_t sync;
-  /** \brief Duration of transaction ending (releasing resources). */
-  uint32_t ending;
-  /** \brief The total duration of a commit. */
-  uint32_t whole;
-};
-#ifndef __cplusplus
-/** \ingroup c_statinfo */
-typedef struct MDBX_commit_latency MDBX_commit_latency;
-#endif
-
-/** \brief Commit all the operations of a transaction into the database and
- * collect latency information.
- * \see mdbx_txn_commit()
- * \ingroup c_statinfo
- * \warning This function may be changed in future releases. */
-LIBMDBX_API int mdbx_txn_commit_ex(MDBX_txn *txn, MDBX_commit_latency *latency);
-
-/** \brief Commit all the operations of a transaction into the database.
- * \ingroup c_transactions
- *
- * If the current thread is not eligible to manage the transaction then
- * the \ref MDBX_THREAD_MISMATCH error will returned. Otherwise the transaction
- * will be committed and its handle is freed. If the transaction cannot
- * be committed, it will be aborted with the corresponding error returned.
- *
- * Thus, a result other than \ref MDBX_THREAD_MISMATCH means that the
- * transaction is terminated:
- *  - Resources are released;
- *  - Transaction handle is invalid;
- *  - Cursor(s) associated with transaction must not be used, except with
- *    mdbx_cursor_renew() and \ref mdbx_cursor_close().
- *    Such cursor(s) must be closed explicitly by \ref mdbx_cursor_close()
- *    before or after transaction commit, either can be reused with
- *    \ref mdbx_cursor_renew() until it will be explicitly closed by
- *    \ref mdbx_cursor_close().
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_RESULT_TRUE      Transaction was aborted since it should
- *                               be aborted due to previous errors.
- * \retval MDBX_PANIC            A fatal error occurred earlier
- *                               and the environment must be shut down.
- * \retval MDBX_BAD_TXN          Transaction is already finished or never began.
- * \retval MDBX_EBADSIGN         Transaction object has invalid signature,
- *                               e.g. transaction was already terminated
- *                               or memory was corrupted.
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL           Transaction handle is NULL.
- * \retval MDBX_ENOSPC           No more disk space.
- * \retval MDBX_EIO              A system-level I/O error occurred.
- * \retval MDBX_ENOMEM           Out of memory. */
-LIBMDBX_INLINE_API(int, mdbx_txn_commit, (MDBX_txn * txn)) {
-  return mdbx_txn_commit_ex(txn, NULL);
-}
-
-/** \brief Abandon all the operations of the transaction instead of saving them.
- * \ingroup c_transactions
- *
- * The transaction handle is freed. It and its cursors must not be used again
- * after this call, except with \ref mdbx_cursor_renew() and
- * \ref mdbx_cursor_close().
- *
- * If the current thread is not eligible to manage the transaction then
- * the \ref MDBX_THREAD_MISMATCH error will returned. Otherwise the transaction
- * will be aborted and its handle is freed. Thus, a result other than
- * \ref MDBX_THREAD_MISMATCH means that the transaction is terminated:
- *  - Resources are released;
- *  - Transaction handle is invalid;
- *  - Cursor(s) associated with transaction must not be used, except with
- *    \ref mdbx_cursor_renew() and \ref mdbx_cursor_close().
- *    Such cursor(s) must be closed explicitly by \ref mdbx_cursor_close()
- *    before or after transaction abort, either can be reused with
- *    \ref mdbx_cursor_renew() until it will be explicitly closed by
- *    \ref mdbx_cursor_close().
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_PANIC            A fatal error occurred earlier and
- *                               the environment must be shut down.
- * \retval MDBX_BAD_TXN          Transaction is already finished or never began.
- * \retval MDBX_EBADSIGN         Transaction object has invalid signature,
- *                               e.g. transaction was already terminated
- *                               or memory was corrupted.
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL           Transaction handle is NULL. */
-LIBMDBX_API int mdbx_txn_abort(MDBX_txn *txn);
-
-/** \brief Marks transaction as broken.
- * \ingroup c_transactions
- *
- * Function keeps the transaction handle and corresponding locks, but it
- * is not possible to perform any operations in a broken transaction.
- * Broken transaction must then be aborted explicitly later.
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \see mdbx_txn_abort() \see mdbx_txn_reset() \see mdbx_txn_commit()
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_txn_break(MDBX_txn *txn);
-
-/** \brief Reset a read-only transaction.
- * \ingroup c_transactions
- *
- * Abort the read-only transaction like \ref mdbx_txn_abort(), but keep the
- * transaction handle. Therefore \ref mdbx_txn_renew() may reuse the handle.
- * This saves allocation overhead if the process will start a new read-only
- * transaction soon, and also locking overhead if \ref MDBX_NOTLS is in use. The
- * reader table lock is released, but the table slot stays tied to its thread
- * or \ref MDBX_txn. Use \ref mdbx_txn_abort() to discard a reset handle, and to
- * free its lock table slot if \ref MDBX_NOTLS is in use.
- *
- * Cursors opened within the transaction must not be used again after this
- * call, except with \ref mdbx_cursor_renew() and \ref mdbx_cursor_close().
- *
- * Reader locks generally don't interfere with writers, but they keep old
- * versions of database pages allocated. Thus they prevent the old pages from
- * being reused when writers commit new data, and so under heavy load the
- * database size may grow much more rapidly than otherwise.
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_PANIC            A fatal error occurred earlier and
- *                               the environment must be shut down.
- * \retval MDBX_BAD_TXN          Transaction is already finished or never began.
- * \retval MDBX_EBADSIGN         Transaction object has invalid signature,
- *                               e.g. transaction was already terminated
- *                               or memory was corrupted.
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL           Transaction handle is NULL. */
-LIBMDBX_API int mdbx_txn_reset(MDBX_txn *txn);
-
-/** \brief Renew a read-only transaction.
- * \ingroup c_transactions
- *
- * This acquires a new reader lock for a transaction handle that had been
- * released by \ref mdbx_txn_reset(). It must be called before a reset
- * transaction may be used again.
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_PANIC            A fatal error occurred earlier and
- *                               the environment must be shut down.
- * \retval MDBX_BAD_TXN          Transaction is already finished or never began.
- * \retval MDBX_EBADSIGN         Transaction object has invalid signature,
- *                               e.g. transaction was already terminated
- *                               or memory was corrupted.
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL           Transaction handle is NULL. */
-LIBMDBX_API int mdbx_txn_renew(MDBX_txn *txn);
-
-/** \brief The fours integers markers (aka "canary") associated with the
- * environment. \ingroup c_crud \see mdbx_canary_set() \see mdbx_canary_get()
- *
- * The `x`, `y` and `z` values could be set by \ref mdbx_canary_put(), while the
- * 'v' will be always set to the transaction number. Updated values becomes
- * visible outside the current transaction only after it was committed. Current
- * values could be retrieved by \ref mdbx_canary_get(). */
-struct MDBX_canary {
-  uint64_t x, y, z, v;
-};
-#ifndef __cplusplus
-/** \ingroup c_crud */
-typedef struct MDBX_canary MDBX_canary;
-#endif
-
-/** \brief Set integers markers (aka "canary") associated with the environment.
- * \ingroup c_crud
- * \see mdbx_canary_get()
- *
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin()
- * \param [in] canary  A optional pointer to \ref MDBX_canary structure for `x`,
- *              `y` and `z` values from.
- *            - If canary is NOT NULL then the `x`, `y` and `z` values will be
- *              updated from given canary argument, but the 'v' be always set
- *              to the current transaction number if at least one `x`, `y` or
- *              `z` values have changed (i.e. if `x`, `y` and `z` have the same
- *              values as currently present then nothing will be changes or
- *              updated).
- *            - if canary is NULL then the `v` value will be explicitly update
- *              to the current transaction number without changes `x`, `y` nor
- *              `z`.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_canary_put(MDBX_txn *txn, const MDBX_canary *canary);
-
-/** \brief Returns fours integers markers (aka "canary") associated with the
- * environment.
- * \ingroup c_crud
- * \see mdbx_canary_set()
- *
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] canary  The address of an MDBX_canary structure where the
- *                     information will be copied.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_canary_get(const MDBX_txn *txn, MDBX_canary *canary);
-
-/** \brief A callback function used to compare two keys in a database
- * \ingroup c_crud
- * \see mdbx_cmp() \see mdbx_get_keycmp()
- * \see mdbx_get_datacmp \see mdbx_dcmp() */
-typedef int(MDBX_cmp_func)(const MDBX_val *a,
-                           const MDBX_val *b) MDBX_CXX17_NOEXCEPT;
-
-/** \brief Open or Create a database in the environment.
- * \ingroup c_dbi
- *
- * A database handle denotes the name and parameters of a database,
- * independently of whether such a database exists. The database handle may be
- * discarded by calling \ref mdbx_dbi_close(). The old database handle is
- * returned if the database was already open. The handle may only be closed
- * once.
- *
- * \note A notable difference between MDBX and LMDB is that MDBX make handles
- * opened for existing databases immediately available for other transactions,
- * regardless this transaction will be aborted or reset. The REASON for this is
- * to avoiding the requirement for multiple opening a same handles in
- * concurrent read transactions, and tracking of such open but hidden handles
- * until the completion of read transactions which opened them.
- *
- * Nevertheless, the handle for the NEWLY CREATED database will be invisible
- * for other transactions until the this write transaction is successfully
- * committed. If the write transaction is aborted the handle will be closed
- * automatically. After a successful commit the such handle will reside in the
- * shared environment, and may be used by other transactions.
- *
- * In contrast to LMDB, the MDBX allow this function to be called from multiple
- * concurrent transactions or threads in the same process.
- *
- * To use named database (with name != NULL), \ref mdbx_env_set_maxdbs()
- * must be called before opening the environment. Table names are
- * keys in the internal unnamed database, and may be read but not written.
- *
- * \param [in] txn    transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] name   The name of the database to open. If only a single
- *                    database is needed in the environment,
- *                    this value may be NULL.
- * \param [in] flags  Special options for this database. This parameter must
- *                    be set to 0 or by bitwise OR'ing together one or more
- *                    of the values described here:
- *  - \ref MDBX_REVERSEKEY
- *      Keys are strings to be compared in reverse order, from the end
- *      of the strings to the beginning. By default, Keys are treated as
- *      strings and compared from beginning to end.
- *  - \ref MDBX_INTEGERKEY
- *      Keys are binary integers in native byte order, either uint32_t or
- *      uint64_t, and will be sorted as such. The keys must all be of the
- *      same size and must be aligned while passing as arguments.
- *  - \ref MDBX_DUPSORT
- *      Duplicate keys may be used in the database. Or, from another point of
- *      view, keys may have multiple data items, stored in sorted order. By
- *      default keys must be unique and may have only a single data item.
- *  - \ref MDBX_DUPFIXED
- *      This flag may only be used in combination with \ref MDBX_DUPSORT. This
- *      option tells the library that the data items for this database are
- *      all the same size, which allows further optimizations in storage and
- *      retrieval. When all data items are the same size, the
- *      \ref MDBX_GET_MULTIPLE, \ref MDBX_NEXT_MULTIPLE and
- *      \ref MDBX_PREV_MULTIPLE cursor operations may be used to retrieve
- *      multiple items at once.
- *  - \ref MDBX_INTEGERDUP
- *      This option specifies that duplicate data items are binary integers,
- *      similar to \ref MDBX_INTEGERKEY keys. The data values must all be of the
- *      same size and must be aligned while passing as arguments.
- *  - \ref MDBX_REVERSEDUP
- *      This option specifies that duplicate data items should be compared as
- *      strings in reverse order (the comparison is performed in the direction
- *      from the last byte to the first).
- *  - \ref MDBX_CREATE
- *      Create the named database if it doesn't exist. This option is not
- *      allowed in a read-only transaction or a read-only environment.
- *
- * \param [out] dbi     Address where the new \ref MDBX_dbi handle
- *                      will be stored.
- *
- * For \ref mdbx_dbi_open_ex() additional arguments allow you to set custom
- * comparison functions for keys and values (for multimaps).
- * However, I recommend not using custom comparison functions, but instead
- * converting the keys to one of the forms that are suitable for built-in
- * comparators (for instance take look to the \ref value2key).
- * The reasons to not using custom comparators are:
- *   - The order of records could not be validated without your code.
- *     So `mdbx_chk` utility will reports "wrong order" errors
- *     and the `-i` option is required to ignore ones.
- *   - A records could not be ordered or sorted without your code.
- *     So mdbx_load utility should be used with `-a` option to preserve
- *     input data order.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_NOTFOUND   The specified database doesn't exist in the
- *                         environment and \ref MDBX_CREATE was not specified.
- * \retval MDBX_DBS_FULL   Too many databases have been opened.
- *                         \see mdbx_env_set_maxdbs()
- * \retval MDBX_INCOMPATIBLE  Database is incompatible with given flags,
- *                         i.e. the passed flags is different with which the
- *                         database was created, or the database was already
- *                         opened with a different comparison function(s).
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread. */
-LIBMDBX_API int mdbx_dbi_open(MDBX_txn *txn, const char *name,
-                              MDBX_db_flags_t flags, MDBX_dbi *dbi);
-
-/** \deprecated Please avoid using custom comparators
- *              and use mdbx_dbi_open() instead.
- * \ingroup c_dbi
- *
- * \param [in] txn    transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] name   The name of the database to open. If only a single
- *                    database is needed in the environment,
- *                    this value may be NULL.
- * \param [in] flags  Special options for this database.
- * \param [in] keycmp  Optional custom key comparison function for a database.
- * \param [in] datacmp Optional custom data comparison function for a database.
- * \param [out] dbi    Address where the new MDBX_dbi handle will be stored.
- * \returns A non-zero error value on failure and 0 on success. */
-MDBX_DEPRECATED LIBMDBX_API int
-mdbx_dbi_open_ex(MDBX_txn *txn, const char *name, MDBX_db_flags_t flags,
-                 MDBX_dbi *dbi, MDBX_cmp_func *keycmp, MDBX_cmp_func *datacmp);
-
-/** \defgroup value2key Value-to-Key functions to avoid custom comparators
- * \see key2value
- * @{
- *
- * The \ref mdbx_key_from_jsonInteger() build a keys which are comparable with
- * keys created by \ref mdbx_key_from_double(). So this allows mixing `int64_t`
- * and IEEE754 double values in one index for JSON-numbers with restriction for
- * integer numbers range corresponding to RFC-7159, i.e. \f$[-2^{53}+1,
- * 2^{53}-1]\f$. See bottom of page 6 at https://tools.ietf.org/html/rfc7159 */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API uint64_t
-mdbx_key_from_jsonInteger(const int64_t json_integer);
-
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API uint64_t
-mdbx_key_from_double(const double ieee754_64bit);
-
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API uint64_t
-mdbx_key_from_ptrdouble(const double *const ieee754_64bit);
-
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API uint32_t
-mdbx_key_from_float(const float ieee754_32bit);
-
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API uint32_t
-mdbx_key_from_ptrfloat(const float *const ieee754_32bit);
-
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_INLINE_API(uint64_t, mdbx_key_from_int64,
-                                               (const int64_t i64)) {
-  return UINT64_C(0x8000000000000000) + i64;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_INLINE_API(uint32_t, mdbx_key_from_int32,
-                                               (const int32_t i32)) {
-  return UINT32_C(0x80000000) + i32;
-}
-/** @} */
-
-/** \defgroup key2value Key-to-Value functions to avoid custom comparators
- * \see value2key
- * @{ */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int64_t
-mdbx_jsonInteger_from_key(const MDBX_val);
-
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API double
-mdbx_double_from_key(const MDBX_val);
-
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API float
-mdbx_float_from_key(const MDBX_val);
-
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int32_t
-mdbx_int32_from_key(const MDBX_val);
-
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int64_t
-mdbx_int64_from_key(const MDBX_val);
-/** @} */
-
-/** \brief Retrieve statistics for a database.
- * \ingroup c_statinfo
- *
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi     A database handle returned by \ref mdbx_dbi_open().
- * \param [out] stat   The address of an \ref MDBX_stat structure where
- *                     the statistics will be copied.
- * \param [in] bytes   The size of \ref MDBX_stat.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL   An invalid parameter was specified. */
-LIBMDBX_API int mdbx_dbi_stat(MDBX_txn *txn, MDBX_dbi dbi, MDBX_stat *stat,
-                              size_t bytes);
-
-/** \brief Retrieve depth (bitmask) information of nested dupsort (multi-value)
- * B+trees for given database.
- * \ingroup c_statinfo
- *
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi     A database handle returned by \ref mdbx_dbi_open().
- * \param [out] mask   The address of an uint32_t value where the bitmask
- *                     will be stored.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL       An invalid parameter was specified.
- * \retval MDBX_RESULT_TRUE  The dbi isn't a dupsort (multi-value) database. */
-LIBMDBX_API int mdbx_dbi_dupsort_depthmask(MDBX_txn *txn, MDBX_dbi dbi,
-                                           uint32_t *mask);
-
-/** \brief DBI state bits returted by \ref mdbx_dbi_flags_ex()
- * \ingroup c_statinfo
- * \see mdbx_dbi_flags_ex() */
-enum MDBX_dbi_state_t {
-  /** DB was written in this txn */
-  MDBX_DBI_DIRTY = 0x01,
-  /** Named-DB record is older than txnID */
-  MDBX_DBI_STALE = 0x02,
-  /** Named-DB handle opened in this txn */
-  MDBX_DBI_FRESH = 0x04,
-  /** Named-DB handle created in this txn */
-  MDBX_DBI_CREAT = 0x08,
-};
-#ifndef __cplusplus
-/** \ingroup c_statinfo */
-typedef enum MDBX_dbi_state_t MDBX_dbi_state_t;
-#else
-DEFINE_ENUM_FLAG_OPERATORS(MDBX_dbi_state_t)
-#endif
-
-/** \brief Retrieve the DB flags and status for a database handle.
- * \ingroup c_statinfo
- *
- * \param [in] txn     A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi     A database handle returned by \ref mdbx_dbi_open().
- * \param [out] flags  Address where the flags will be returned.
- * \param [out] state  Address where the state will be returned.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_dbi_flags_ex(MDBX_txn *txn, MDBX_dbi dbi, unsigned *flags,
-                                  unsigned *state);
-/** \brief The shortcut to calling \ref mdbx_dbi_flags_ex() with `state=NULL`
- * for discarding it result. \ingroup c_statinfo */
-LIBMDBX_INLINE_API(int, mdbx_dbi_flags,
-                   (MDBX_txn * txn, MDBX_dbi dbi, unsigned *flags)) {
-  unsigned state;
-  return mdbx_dbi_flags_ex(txn, dbi, flags, &state);
-}
-
-/** \brief Close a database handle. Normally unnecessary.
- * \ingroup c_dbi
- *
- * Closing a database handle is not necessary, but lets \ref mdbx_dbi_open()
- * reuse the handle value. Usually it's better to set a bigger
- * \ref mdbx_env_set_maxdbs(), unless that value would be large.
- *
- * \note Use with care.
- * This call is synchronized via mutex with \ref mdbx_dbi_close(), but NOT with
- * other transactions running by other threads. The "next" version of libmdbx
- * (\ref MithrilDB) will solve this issue.
- *
- * Handles should only be closed if no other threads are going to reference
- * the database handle or one of its cursors any further. Do not close a handle
- * if an existing transaction has modified its database. Doing so can cause
- * misbehavior from database corruption to errors like \ref MDBX_BAD_DBI
- * (since the DB name is gone).
- *
- * \param [in] env  An environment handle returned by \ref mdbx_env_create().
- * \param [in] dbi  A database handle returned by \ref mdbx_dbi_open().
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_dbi_close(MDBX_env *env, MDBX_dbi dbi);
-
-/** \brief Empty or delete and close a database.
- * \ingroup c_crud
- *
- * \see mdbx_dbi_close() \see mdbx_dbi_open()
- *
- * \param [in] txn  A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi  A database handle returned by \ref mdbx_dbi_open().
- * \param [in] del  `false` to empty the DB, `true` to delete it
- *                  from the environment and close the DB handle.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_drop(MDBX_txn *txn, MDBX_dbi dbi, bool del);
-
-/** \brief Get items from a database.
- * \ingroup c_crud
- *
- * This function retrieves key/data pairs from the database. The address
- * and length of the data associated with the specified key are returned
- * in the structure to which data refers.
- * If the database supports duplicate keys (\ref MDBX_DUPSORT) then the
- * first data item for the key will be returned. Retrieval of other
- * items requires the use of \ref mdbx_cursor_get().
- *
- * \note The memory pointed to by the returned values is owned by the
- * database. The caller need not dispose of the memory, and may not
- * modify it in any way. For values returned in a read-only transaction
- * any modification attempts will cause a `SIGSEGV`.
- *
- * \note Values returned from the database are valid only until a
- * subsequent update operation, or the end of the transaction.
- *
- * \param [in] txn       A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi       A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key       The key to search for in the database.
- * \param [in,out] data  The data corresponding to the key.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_NOTFOUND  The key was not in the database.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_get(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                         MDBX_val *data);
-
-/** \brief Get items from a database
- * and optionally number of data items for a given key.
- *
- * \ingroup c_crud
- *
- * Briefly this function does the same as \ref mdbx_get() with a few
- * differences:
- *  1. If values_count is NOT NULL, then returns the count
- *     of multi-values/duplicates for a given key.
- *  2. Updates BOTH the key and the data for pointing to the actual key-value
- *     pair inside the database.
- *
- * \param [in] txn           A transaction handle returned
- *                           by \ref mdbx_txn_begin().
- * \param [in] dbi           A database handle returned by \ref mdbx_dbi_open().
- * \param [in,out] key       The key to search for in the database.
- * \param [in,out] data      The data corresponding to the key.
- * \param [out] values_count The optional address to return number of values
- *                           associated with given key:
- *                            = 0 - in case \ref MDBX_NOTFOUND error;
- *                            = 1 - exactly for databases
- *                                  WITHOUT \ref MDBX_DUPSORT;
- *                            >= 1 for databases WITH \ref MDBX_DUPSORT.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_NOTFOUND  The key was not in the database.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_get_ex(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key,
-                            MDBX_val *data, size_t *values_count);
-
-/** \brief Get equal or great item from a database.
- * \ingroup c_crud
- *
- * Briefly this function does the same as \ref mdbx_get() with a few
- * differences:
- * 1. Return equal or great (due comparison function) key-value
- *    pair, but not only exactly matching with the key.
- * 2. On success return \ref MDBX_SUCCESS if key found exactly,
- *    and \ref MDBX_RESULT_TRUE otherwise. Moreover, for databases with
- *    \ref MDBX_DUPSORT flag the data argument also will be used to match over
- *    multi-value/duplicates, and \ref MDBX_SUCCESS will be returned only when
- *    BOTH the key and the data match exactly.
- * 3. Updates BOTH the key and the data for pointing to the actual key-value
- *    pair inside the database.
- *
- * \param [in] txn           A transaction handle returned
- *                           by \ref mdbx_txn_begin().
- * \param [in] dbi           A database handle returned by \ref mdbx_dbi_open().
- * \param [in,out] key       The key to search for in the database.
- * \param [in,out] data      The data corresponding to the key.
- *
- * \returns A non-zero error value on failure and \ref MDBX_RESULT_FALSE
- *          or \ref MDBX_RESULT_TRUE on success (as described above).
- *          Some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_NOTFOUND      The key was not in the database.
- * \retval MDBX_EINVAL        An invalid parameter was specified. */
-LIBMDBX_API int mdbx_get_equal_or_great(MDBX_txn *txn, MDBX_dbi dbi,
-                                        MDBX_val *key, MDBX_val *data);
-
-/** \brief Store items into a database.
- * \ingroup c_crud
- *
- * This function stores key/data pairs in the database. The default behavior
- * is to enter the new key/data pair, replacing any previously existing key
- * if duplicates are disallowed, or adding a duplicate data item if
- * duplicates are allowed (see \ref MDBX_DUPSORT).
- *
- * \param [in] txn        A transaction handle returned
- *                        by \ref mdbx_txn_begin().
- * \param [in] dbi        A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key        The key to store in the database.
- * \param [in,out] data   The data to store.
- * \param [in] flags      Special options for this operation.
- *                        This parameter must be set to 0 or by bitwise OR'ing
- *                        together one or more of the values described here:
- *   - \ref MDBX_NODUPDATA
- *      Enter the new key-value pair only if it does not already appear
- *      in the database. This flag may only be specified if the database
- *      was opened with \ref MDBX_DUPSORT. The function will return
- *      \ref MDBX_KEYEXIST if the key/data pair already appears in the database.
- *
- *  - \ref MDBX_NOOVERWRITE
- *      Enter the new key/data pair only if the key does not already appear
- *      in the database. The function will return \ref MDBX_KEYEXIST if the key
- *      already appears in the database, even if the database supports
- *      duplicates (see \ref  MDBX_DUPSORT). The data parameter will be set
- *      to point to the existing item.
- *
- *  - \ref MDBX_CURRENT
- *      Update an single existing entry, but not add new ones. The function will
- *      return \ref MDBX_NOTFOUND if the given key not exist in the database.
- *      In case multi-values for the given key, with combination of
- *      the \ref MDBX_ALLDUPS will replace all multi-values,
- *      otherwise return the \ref MDBX_EMULTIVAL.
- *
- *  - \ref MDBX_RESERVE
- *      Reserve space for data of the given size, but don't copy the given
- *      data. Instead, return a pointer to the reserved space, which the
- *      caller can fill in later - before the next update operation or the
- *      transaction ends. This saves an extra memcpy if the data is being
- *      generated later. MDBX does nothing else with this memory, the caller
- *      is expected to modify all of the space requested. This flag must not
- *      be specified if the database was opened with \ref MDBX_DUPSORT.
- *
- *  - \ref MDBX_APPEND
- *      Append the given key/data pair to the end of the database. This option
- *      allows fast bulk loading when keys are already known to be in the
- *      correct order. Loading unsorted keys with this flag will cause
- *      a \ref MDBX_EKEYMISMATCH error.
- *
- *  - \ref MDBX_APPENDDUP
- *      As above, but for sorted dup data.
- *
- *  - \ref MDBX_MULTIPLE
- *      Store multiple contiguous data elements in a single request. This flag
- *      may only be specified if the database was opened with
- *      \ref MDBX_DUPFIXED. With combination the \ref MDBX_ALLDUPS
- *      will replace all multi-values.
- *      The data argument must be an array of two \ref MDBX_val. The `iov_len`
- *      of the first \ref MDBX_val must be the size of a single data element.
- *      The `iov_base` of the first \ref MDBX_val must point to the beginning
- *      of the array of contiguous data elements which must be properly aligned
- *      in case of database with \ref MDBX_INTEGERDUP flag.
- *      The `iov_len` of the second \ref MDBX_val must be the count of the
- *      number of data elements to store. On return this field will be set to
- *      the count of the number of elements actually written. The `iov_base` of
- *      the second \ref MDBX_val is unused.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_KEYEXIST  The key/value pair already exists in the database.
- * \retval MDBX_MAP_FULL  The database is full, see \ref mdbx_env_set_mapsize().
- * \retval MDBX_TXN_FULL  The transaction has too many dirty pages.
- * \retval MDBX_EACCES    An attempt was made to write
- *                        in a read-only transaction.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_put(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                         MDBX_val *data, MDBX_put_flags_t flags);
-
-/** \brief Replace items in a database.
- * \ingroup c_crud
- *
- * This function allows to update or delete an existing value at the same time
- * as the previous value is retrieved. If the argument new_data equal is NULL
- * zero, the removal is performed, otherwise the update/insert.
- *
- * The current value may be in an already changed (aka dirty) page. In this
- * case, the page will be overwritten during the update, and the old value will
- * be lost. Therefore, an additional buffer must be passed via old_data
- * argument initially to copy the old value. If the buffer passed in is too
- * small, the function will return \ref MDBX_RESULT_TRUE by setting iov_len
- * field pointed by old_data argument to the appropriate value, without
- * performing any changes.
- *
- * For databases with non-unique keys (i.e. with \ref MDBX_DUPSORT flag),
- * another use case is also possible, when by old_data argument selects a
- * specific item from multi-value/duplicates with the same key for deletion or
- * update. To select this scenario in flags should simultaneously specify
- * \ref MDBX_CURRENT and \ref MDBX_NOOVERWRITE. This combination is chosen
- * because it makes no sense, and thus allows you to identify the request of
- * such a scenario.
- *
- * \param [in] txn           A transaction handle returned
- *                           by \ref mdbx_txn_begin().
- * \param [in] dbi           A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key           The key to store in the database.
- * \param [in] new_data      The data to store, if NULL then deletion will
- *                           be performed.
- * \param [in,out] old_data  The buffer for retrieve previous value as describe
- *                           above.
- * \param [in] flags         Special options for this operation.
- *                           This parameter must be set to 0 or by bitwise
- *                           OR'ing together one or more of the values
- *                           described in \ref mdbx_put() description above,
- *                           and additionally
- *                           (\ref MDBX_CURRENT | \ref MDBX_NOOVERWRITE)
- *                           combination for selection particular item from
- *                           multi-value/duplicates.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_replace(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                             MDBX_val *new_data, MDBX_val *old_data,
-                             MDBX_put_flags_t flags);
-
-typedef int (*MDBX_preserve_func)(void *context, MDBX_val *target,
-                                  const void *src, size_t bytes);
-LIBMDBX_API int mdbx_replace_ex(MDBX_txn *txn, MDBX_dbi dbi,
-                                const MDBX_val *key, MDBX_val *new_data,
-                                MDBX_val *old_data, MDBX_put_flags_t flags,
-                                MDBX_preserve_func preserver,
-                                void *preserver_context);
-
-/** \brief Delete items from a database.
- * \ingroup c_crud
- *
- * This function removes key/data pairs from the database.
- *
- * \note The data parameter is NOT ignored regardless the database does
- * support sorted duplicate data items or not. If the data parameter
- * is non-NULL only the matching data item will be deleted. Otherwise, if data
- * parameter is NULL, any/all value(s) for specified key will be deleted.
- *
- * This function will return \ref MDBX_NOTFOUND if the specified key/data
- * pair is not in the database.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \param [in] txn   A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi   A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key   The key to delete from the database.
- * \param [in] data  The data to delete.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EACCES   An attempt was made to write
- *                       in a read-only transaction.
- * \retval MDBX_EINVAL   An invalid parameter was specified. */
-LIBMDBX_API int mdbx_del(MDBX_txn *txn, MDBX_dbi dbi, const MDBX_val *key,
-                         const MDBX_val *data);
-
-/** \brief Create a cursor handle but not bind it to transaction nor DBI handle.
- * \ingroup c_cursors
- *
- * An capable of operation cursor is associated with a specific transaction and
- * database. A cursor cannot be used when its database handle is closed. Nor
- * when its transaction has ended, except with \ref mdbx_cursor_bind() and
- * \ref mdbx_cursor_renew().
- * Also it can be discarded with \ref mdbx_cursor_close().
- *
- * A cursor must be closed explicitly always, before or after its transaction
- * ends. It can be reused with \ref mdbx_cursor_bind()
- * or \ref mdbx_cursor_renew() before finally closing it.
- *
- * \note In contrast to LMDB, the MDBX required that any opened cursors can be
- * reused and must be freed explicitly, regardless ones was opened in a
- * read-only or write transaction. The REASON for this is eliminates ambiguity
- * which helps to avoid errors such as: use-after-free, double-free, i.e.
- * memory corruption and segfaults.
- *
- * \param [in] context A pointer to application context to be associated with
- *                     created cursor and could be retrieved by
- *                     \ref mdbx_cursor_get_userctx() until cursor closed.
- *
- * \returns Created cursor handle or NULL in case out of memory. */
-LIBMDBX_API MDBX_cursor *mdbx_cursor_create(void *context);
-
-/** \brief Set application information associated with the \ref MDBX_cursor.
- * \ingroup c_cursors
- * \see mdbx_cursor_get_userctx()
- *
- * \param [in] cursor  An cursor handle returned by \ref mdbx_cursor_create()
- *                     or \ref mdbx_cursor_open().
- * \param [in] ctx     An arbitrary pointer for whatever the application needs.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_cursor_set_userctx(MDBX_cursor *cursor, void *ctx);
-
-/** \brief Get the application information associated with the MDBX_cursor.
- * \ingroup c_cursors
- * \see mdbx_cursor_set_userctx()
- *
- * \param [in] cursor  An cursor handle returned by \ref mdbx_cursor_create()
- *                     or \ref mdbx_cursor_open().
- * \returns The pointer which was passed via the `context` parameter
- *          of `mdbx_cursor_create()` or set by \ref mdbx_cursor_set_userctx(),
- *          or `NULL` if something wrong. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API void *
-mdbx_cursor_get_userctx(const MDBX_cursor *cursor);
-
-/** \brief Bind cursor to specified transaction and DBI handle.
- * \ingroup c_cursors
- *
- * Using of the `mdbx_cursor_bind()` is equivalent to calling
- * \ref mdbx_cursor_renew() but with specifying an arbitrary dbi handle.
- *
- * An capable of operation cursor is associated with a specific transaction and
- * database. The cursor may be associated with a new transaction,
- * and referencing a new or the same database handle as it was created with.
- * This may be done whether the previous transaction is live or dead.
- *
- * \note In contrast to LMDB, the MDBX required that any opened cursors can be
- * reused and must be freed explicitly, regardless ones was opened in a
- * read-only or write transaction. The REASON for this is eliminates ambiguity
- * which helps to avoid errors such as: use-after-free, double-free, i.e.
- * memory corruption and segfaults.
- *
- * \param [in] txn      A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi      A database handle returned by \ref mdbx_dbi_open().
- * \param [out] cursor  A cursor handle returned by \ref mdbx_cursor_create().
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL  An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_bind(MDBX_txn *txn, MDBX_cursor *cursor,
-                                 MDBX_dbi dbi);
-
-/** \brief Create a cursor handle for the specified transaction and DBI handle.
- * \ingroup c_cursors
- *
- * Using of the `mdbx_cursor_open()` is equivalent to calling
- * \ref mdbx_cursor_create() and then \ref mdbx_cursor_bind() functions.
- *
- * An capable of operation cursor is associated with a specific transaction and
- * database. A cursor cannot be used when its database handle is closed. Nor
- * when its transaction has ended, except with \ref mdbx_cursor_bind() and
- * \ref mdbx_cursor_renew().
- * Also it can be discarded with \ref mdbx_cursor_close().
- *
- * A cursor must be closed explicitly always, before or after its transaction
- * ends. It can be reused with \ref mdbx_cursor_bind()
- * or \ref mdbx_cursor_renew() before finally closing it.
- *
- * \note In contrast to LMDB, the MDBX required that any opened cursors can be
- * reused and must be freed explicitly, regardless ones was opened in a
- * read-only or write transaction. The REASON for this is eliminates ambiguity
- * which helps to avoid errors such as: use-after-free, double-free, i.e.
- * memory corruption and segfaults.
- *
- * \param [in] txn      A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi      A database handle returned by \ref mdbx_dbi_open().
- * \param [out] cursor  Address where the new \ref MDBX_cursor handle will be
- *                      stored.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL  An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_open(MDBX_txn *txn, MDBX_dbi dbi,
-                                 MDBX_cursor **cursor);
-
-/** \brief Close a cursor handle.
- * \ingroup c_cursors
- *
- * The cursor handle will be freed and must not be used again after this call,
- * but its transaction may still be live.
- *
- * \note In contrast to LMDB, the MDBX required that any opened cursors can be
- * reused and must be freed explicitly, regardless ones was opened in a
- * read-only or write transaction. The REASON for this is eliminates ambiguity
- * which helps to avoid errors such as: use-after-free, double-free, i.e.
- * memory corruption and segfaults.
- *
- * \param [in] cursor  A cursor handle returned by \ref mdbx_cursor_open()
- *                     or \ref mdbx_cursor_create(). */
-LIBMDBX_API void mdbx_cursor_close(MDBX_cursor *cursor);
-
-/** \brief Renew a cursor handle.
- * \ingroup c_cursors
- *
- * An capable of operation cursor is associated with a specific transaction and
- * database. The cursor may be associated with a new transaction,
- * and referencing a new or the same database handle as it was created with.
- * This may be done whether the previous transaction is live or dead.
- *
- * Using of the `mdbx_cursor_renew()` is equivalent to calling
- * \ref mdbx_cursor_bind() with the DBI handle that previously
- * the cursor was used with.
- *
- * \note In contrast to LMDB, the MDBX allow any cursor to be re-used by using
- * \ref mdbx_cursor_renew(), to avoid unnecessary malloc/free overhead until it
- * freed by \ref mdbx_cursor_close().
- *
- * \param [in] txn      A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] cursor   A cursor handle returned by \ref mdbx_cursor_open().
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL  An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_renew(MDBX_txn *txn, MDBX_cursor *cursor);
-
-/** \brief Return the cursor's transaction handle.
- * \ingroup c_cursors
- *
- * \param [in] cursor A cursor handle returned by \ref mdbx_cursor_open(). */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API MDBX_txn *
-mdbx_cursor_txn(const MDBX_cursor *cursor);
-
-/** \brief Return the cursor's database handle.
- * \ingroup c_cursors
- *
- * \param [in] cursor  A cursor handle returned by \ref mdbx_cursor_open(). */
-LIBMDBX_API MDBX_dbi mdbx_cursor_dbi(const MDBX_cursor *cursor);
-
-/** \brief Copy cursor position and state.
- * \ingroup c_cursors
- *
- * \param [in] src       A source cursor handle returned
- * by \ref mdbx_cursor_create() or \ref mdbx_cursor_open().
- *
- * \param [in,out] dest  A destination cursor handle returned
- * by \ref mdbx_cursor_create() or \ref mdbx_cursor_open().
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_cursor_copy(const MDBX_cursor *src, MDBX_cursor *dest);
-
-/** \brief Retrieve by cursor.
- * \ingroup c_cursors c_crud
- *
- * This function retrieves key/data pairs from the database. The address and
- * length of the key are returned in the object to which key refers (except
- * for the case of the \ref MDBX_SET option, in which the key object is
- * unchanged), and the address and length of the data are returned in the object
- * to which data refers.
- * \see mdbx_get()
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- * \param [in,out] key   The key for a retrieved item.
- * \param [in,out] data  The data of a retrieved item.
- * \param [in] op        A cursor operation \ref MDBX_cursor_op.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_NOTFOUND  No matching key found.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_get(MDBX_cursor *cursor, MDBX_val *key,
-                                MDBX_val *data, MDBX_cursor_op op);
-
-/** \brief Store by cursor.
- * \ingroup c_cursors c_crud
- *
- * This function stores key/data pairs into the database. The cursor is
- * positioned at the new item, or on failure usually near it.
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- * \param [in] key       The key operated on.
- * \param [in,out] data  The data operated on.
- * \param [in] flags     Options for this operation. This parameter
- *                       must be set to 0 or by bitwise OR'ing together
- *                       one or more of the values described here:
- *  - \ref MDBX_CURRENT
- *      Replace the item at the current cursor position. The key parameter
- *      must still be provided, and must match it, otherwise the function
- *      return \ref MDBX_EKEYMISMATCH. With combination the
- *      \ref MDBX_ALLDUPS will replace all multi-values.
- *
- *      \note MDBX allows (unlike LMDB) you to change the size of the data and
- *      automatically handles reordering for sorted duplicates
- *      (see \ref MDBX_DUPSORT).
- *
- *  - \ref MDBX_NODUPDATA
- *      Enter the new key-value pair only if it does not already appear in the
- *      database. This flag may only be specified if the database was opened
- *      with \ref MDBX_DUPSORT. The function will return \ref MDBX_KEYEXIST
- *      if the key/data pair already appears in the database.
- *
- *  - \ref MDBX_NOOVERWRITE
- *      Enter the new key/data pair only if the key does not already appear
- *      in the database. The function will return \ref MDBX_KEYEXIST if the key
- *      already appears in the database, even if the database supports
- *      duplicates (\ref MDBX_DUPSORT).
- *
- *  - \ref MDBX_RESERVE
- *      Reserve space for data of the given size, but don't copy the given
- *      data. Instead, return a pointer to the reserved space, which the
- *      caller can fill in later - before the next update operation or the
- *      transaction ends. This saves an extra memcpy if the data is being
- *      generated later. This flag must not be specified if the database
- *      was opened with \ref MDBX_DUPSORT.
- *
- *  - \ref MDBX_APPEND
- *      Append the given key/data pair to the end of the database. No key
- *      comparisons are performed. This option allows fast bulk loading when
- *      keys are already known to be in the correct order. Loading unsorted
- *      keys with this flag will cause a \ref MDBX_KEYEXIST error.
- *
- *  - \ref MDBX_APPENDDUP
- *      As above, but for sorted dup data.
- *
- *  - \ref MDBX_MULTIPLE
- *      Store multiple contiguous data elements in a single request. This flag
- *      may only be specified if the database was opened with
- *      \ref MDBX_DUPFIXED. With combination the \ref MDBX_ALLDUPS
- *      will replace all multi-values.
- *      The data argument must be an array of two \ref MDBX_val. The `iov_len`
- *      of the first \ref MDBX_val must be the size of a single data element.
- *      The `iov_base` of the first \ref MDBX_val must point to the beginning
- *      of the array of contiguous data elements which must be properly aligned
- *      in case of database with \ref MDBX_INTEGERDUP flag.
- *      The `iov_len` of the second \ref MDBX_val must be the count of the
- *      number of data elements to store. On return this field will be set to
- *      the count of the number of elements actually written. The `iov_base` of
- *      the second \ref MDBX_val is unused.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EKEYMISMATCH  The given key value is mismatched to the current
- *                            cursor position
- * \retval MDBX_MAP_FULL      The database is full,
- *                             see \ref mdbx_env_set_mapsize().
- * \retval MDBX_TXN_FULL      The transaction has too many dirty pages.
- * \retval MDBX_EACCES        An attempt was made to write in a read-only
- *                            transaction.
- * \retval MDBX_EINVAL        An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_put(MDBX_cursor *cursor, const MDBX_val *key,
-                                MDBX_val *data, MDBX_put_flags_t flags);
-
-/** \brief Delete current key/data pair.
- * \ingroup c_cursors c_crud
- *
- * This function deletes the key/data pair to which the cursor refers. This
- * does not invalidate the cursor, so operations such as \ref MDBX_NEXT can
- * still be used on it. Both \ref MDBX_NEXT and \ref MDBX_GET_CURRENT will
- * return the same record after this operation.
- *
- * \param [in] cursor  A cursor handle returned by mdbx_cursor_open().
- * \param [in] flags   Options for this operation. This parameter must be set
- * to one of the values described here.
- *
- *  - \ref MDBX_CURRENT Delete only single entry at current cursor position.
- *  - \ref MDBX_ALLDUPS
- *    or \ref MDBX_NODUPDATA (supported for compatibility)
- *      Delete all of the data items for the current key. This flag has effect
- *      only for database(s) was created with \ref MDBX_DUPSORT.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_MAP_FULL      The database is full,
- *                            see \ref mdbx_env_set_mapsize().
- * \retval MDBX_TXN_FULL      The transaction has too many dirty pages.
- * \retval MDBX_EACCES        An attempt was made to write in a read-only
- *                            transaction.
- * \retval MDBX_EINVAL        An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_del(MDBX_cursor *cursor, MDBX_put_flags_t flags);
-
-/** \brief Return count of duplicates for current key.
- * \ingroup c_cursors c_crud
- *
- * This call is valid for all databases, but reasonable only for that support
- * sorted duplicate data items \ref MDBX_DUPSORT.
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- * \param [out] pcount   Address where the count will be stored.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_THREAD_MISMATCH  Given transaction is not owned
- *                               by current thread.
- * \retval MDBX_EINVAL   Cursor is not initialized, or an invalid parameter
- *                       was specified. */
-LIBMDBX_API int mdbx_cursor_count(const MDBX_cursor *cursor, size_t *pcount);
-
-/** \brief Determines whether the cursor is pointed to a key-value pair or not,
- * i.e. was not positioned or points to the end of data.
- * \ingroup c_cursors
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- *
- * \returns A \ref MDBX_RESULT_TRUE or \ref MDBX_RESULT_FALSE value,
- *          otherwise the error code:
- * \retval MDBX_RESULT_TRUE    No more data available or cursor not
- *                             positioned
- * \retval MDBX_RESULT_FALSE   A data is available
- * \retval Otherwise the error code */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
-mdbx_cursor_eof(const MDBX_cursor *cursor);
-
-/** \brief Determines whether the cursor is pointed to the first key-value pair
- * or not. \ingroup c_cursors
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- *
- * \returns A MDBX_RESULT_TRUE or MDBX_RESULT_FALSE value,
- *          otherwise the error code:
- * \retval MDBX_RESULT_TRUE   Cursor positioned to the first key-value pair
- * \retval MDBX_RESULT_FALSE  Cursor NOT positioned to the first key-value
- * pair \retval Otherwise the error code */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
-mdbx_cursor_on_first(const MDBX_cursor *cursor);
-
-/** \brief Determines whether the cursor is pointed to the last key-value pair
- * or not. \ingroup c_cursors
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- *
- * \returns A \ref MDBX_RESULT_TRUE or \ref MDBX_RESULT_FALSE value,
- *          otherwise the error code:
- * \retval MDBX_RESULT_TRUE   Cursor positioned to the last key-value pair
- * \retval MDBX_RESULT_FALSE  Cursor NOT positioned to the last key-value pair
- * \retval Otherwise the error code */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
-mdbx_cursor_on_last(const MDBX_cursor *cursor);
-
-/** \addtogroup c_rqest
- * \details \note The estimation result varies greatly depending on the filling
- * of specific pages and the overall balance of the b-tree:
- *
- * 1. The number of items is estimated by analyzing the height and fullness of
- * the b-tree. The accuracy of the result directly depends on the balance of
- * the b-tree, which in turn is determined by the history of previous
- * insert/delete operations and the nature of the data (i.e. variability of
- * keys length and so on). Therefore, the accuracy of the estimation can vary
- * greatly in a particular situation.
- *
- * 2. To understand the potential spread of results, you should consider a
- * possible situations basing on the general criteria for splitting and merging
- * b-tree pages:
- *  - the page is split into two when there is no space for added data;
- *  - two pages merge if the result fits in half a page;
- *  - thus, the b-tree can consist of an arbitrary combination of pages filled
- *    both completely and only 1/4. Therefore, in the worst case, the result
- *    can diverge 4 times for each level of the b-tree excepting the first and
- *    the last.
- *
- * 3. In practice, the probability of extreme cases of the above situation is
- * close to zero and in most cases the error does not exceed a few percent. On
- * the other hand, it's just a chance you shouldn't overestimate. */
-
-/** \brief Estimates the distance between cursors as a number of elements.
- * \ingroup c_rqest
- *
- * This function performs a rough estimate based only on b-tree pages that are
- * common for the both cursor's stacks. The results of such estimation can be
- * used to build and/or optimize query execution plans.
- *
- * Please see notes on accuracy of the result in the details
- * of \ref c_rqest section.
- *
- * Both cursors must be initialized for the same database and the same
- * transaction.
- *
- * \param [in] first            The first cursor for estimation.
- * \param [in] last             The second cursor for estimation.
- * \param [out] distance_items  The pointer to store estimated distance value,
- *                              i.e. `*distance_items = distance(first, last)`.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_estimate_distance(const MDBX_cursor *first,
-                                       const MDBX_cursor *last,
-                                       ptrdiff_t *distance_items);
-
-/** \brief Estimates the move distance.
- * \ingroup c_rqest
- *
- * This function performs a rough estimate distance between the current
- * cursor position and next position after the specified move-operation with
- * given key and data. The results of such estimation can be used to build
- * and/or optimize query execution plans. Current cursor position and state are
- * preserved.
- *
- * Please see notes on accuracy of the result in the details
- * of \ref c_rqest section.
- *
- * \param [in] cursor            Cursor for estimation.
- * \param [in,out] key           The key for a retrieved item.
- * \param [in,out] data          The data of a retrieved item.
- * \param [in] move_op           A cursor operation \ref MDBX_cursor_op.
- * \param [out] distance_items   A pointer to store estimated move distance
- *                               as the number of elements.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_estimate_move(const MDBX_cursor *cursor, MDBX_val *key,
-                                   MDBX_val *data, MDBX_cursor_op move_op,
-                                   ptrdiff_t *distance_items);
-
-/** \brief Estimates the size of a range as a number of elements.
- * \ingroup c_rqest
- *
- * The results of such estimation can be used to build and/or optimize query
- * execution plans.
- *
- * Please see notes on accuracy of the result in the details
- * of \ref c_rqest section.
- *
- *
- * \param [in] txn        A transaction handle returned
- *                        by \ref mdbx_txn_begin().
- * \param [in] dbi        A database handle returned by  \ref mdbx_dbi_open().
- * \param [in] begin_key  The key of range beginning or NULL for explicit FIRST.
- * \param [in] begin_data Optional additional data to seeking among sorted
- *                        duplicates.
- *                        Only for \ref MDBX_DUPSORT, NULL otherwise.
- * \param [in] end_key    The key of range ending or NULL for explicit LAST.
- * \param [in] end_data   Optional additional data to seeking among sorted
- *                        duplicates.
- *                        Only for \ref MDBX_DUPSORT, NULL otherwise.
- * \param [out] distance_items  A pointer to store range estimation result.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_estimate_range(MDBX_txn *txn, MDBX_dbi dbi,
-                                    MDBX_val *begin_key, MDBX_val *begin_data,
-                                    MDBX_val *end_key, MDBX_val *end_data,
-                                    ptrdiff_t *distance_items);
-
-/** \brief The EPSILON value for mdbx_estimate_range()
- * \ingroup c_rqest */
-#define MDBX_EPSILON ((MDBX_val *)((ptrdiff_t)-1))
-
-/** \brief Determines whether the given address is on a dirty database page of
- * the transaction or not. \ingroup c_statinfo
- *
- * Ultimately, this allows to avoid copy data from non-dirty pages.
- *
- * "Dirty" pages are those that have already been changed during a write
- * transaction. Accordingly, any further changes may result in such pages being
- * overwritten. Therefore, all functions libmdbx performing changes inside the
- * database as arguments should NOT get pointers to data in those pages. In
- * turn, "not dirty" pages before modification will be copied.
- *
- * In other words, data from dirty pages must either be copied before being
- * passed as arguments for further processing or rejected at the argument
- * validation stage. Thus, `mdbx_is_dirty()` allows you to get rid of
- * unnecessary copying, and perform a more complete check of the arguments.
- *
- * \note The address passed must point to the beginning of the data. This is
- * the only way to ensure that the actual page header is physically located in
- * the same memory page, including for multi-pages with long data.
- *
- * \note In rare cases the function may return a false positive answer
- * (\ref MDBX_RESULT_TRUE when data is NOT on a dirty page), but never a false
- * negative if the arguments are correct.
- *
- * \param [in] txn      A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] ptr      The address of data to check.
- *
- * \returns A MDBX_RESULT_TRUE or MDBX_RESULT_FALSE value,
- *          otherwise the error code:
- * \retval MDBX_RESULT_TRUE    Given address is on the dirty page.
- * \retval MDBX_RESULT_FALSE   Given address is NOT on the dirty page.
- * \retval Otherwise the error code. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int mdbx_is_dirty(const MDBX_txn *txn,
-                                                         const void *ptr);
-
-/** \brief Sequence generation for a database.
- * \ingroup c_crud
- *
- * The function allows to create a linear sequence of unique positive integers
- * for each database. The function can be called for a read transaction to
- * retrieve the current sequence value, and the increment must be zero.
- * Sequence changes become visible outside the current write transaction after
- * it is committed, and discarded on abort.
- *
- * \param [in] txn        A transaction handle returned
- *                        by \ref mdbx_txn_begin().
- * \param [in] dbi        A database handle returned by \ref mdbx_dbi_open().
- * \param [out] result    The optional address where the value of sequence
- *                        before the change will be stored.
- * \param [in] increment  Value to increase the sequence,
- *                        must be 0 for read-only transactions.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_RESULT_TRUE   Increasing the sequence has resulted in an
- *                            overflow and therefore cannot be executed. */
-LIBMDBX_API int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
-                                  uint64_t increment);
-
-/** \brief Compare two keys according to a particular database.
- * \ingroup c_crud
- *
- * This returns a comparison as if the two data items were keys in the
- * specified database.
- *
- * \warning There ss a Undefined behavior if one of arguments is invalid.
- *
- * \param [in] txn   A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi   A database handle returned by \ref mdbx_dbi_open().
- * \param [in] a     The first item to compare.
- * \param [in] b     The second item to compare.
- *
- * \returns < 0 if a < b, 0 if a == b, > 0 if a > b */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int mdbx_cmp(const MDBX_txn *txn,
-                                                    MDBX_dbi dbi,
-                                                    const MDBX_val *a,
-                                                    const MDBX_val *b);
-
-/** \brief Returns default internal key's comparator for given database flags.
- * \ingroup c_extra */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API MDBX_cmp_func *
-mdbx_get_keycmp(MDBX_db_flags_t flags);
-
-/** \brief Compare two data items according to a particular database.
- * \ingroup c_crud
- *
- * This returns a comparison as if the two items were data items of the
- * specified database.
- *
- * \warning There ss a Undefined behavior if one of arguments is invalid.
- *
- * \param [in] txn   A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi   A database handle returned by \ref mdbx_dbi_open().
- * \param [in] a     The first item to compare.
- * \param [in] b     The second item to compare.
- *
- * \returns < 0 if a < b, 0 if a == b, > 0 if a > b */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int mdbx_dcmp(const MDBX_txn *txn,
-                                                     MDBX_dbi dbi,
-                                                     const MDBX_val *a,
-                                                     const MDBX_val *b);
-
-/** \brief Returns default internal data's comparator for given database flags
- * \ingroup c_extra */
-MDBX_NOTHROW_CONST_FUNCTION LIBMDBX_API MDBX_cmp_func *
-mdbx_get_datacmp(MDBX_db_flags_t flags);
-
-/** \brief A callback function used to enumerate the reader lock table.
- * \ingroup c_statinfo
- *
- * \param [in] ctx           An arbitrary context pointer for the callback.
- * \param [in] num           The serial number during enumeration,
- *                           starting from 1.
- * \param [in] slot          The reader lock table slot number.
- * \param [in] txnid         The ID of the transaction being read,
- *                           i.e. the MVCC-snapshot number.
- * \param [in] lag           The lag from a recent MVCC-snapshot,
- *                           i.e. the number of committed write transactions
- *                           since the current read transaction started.
- * \param [in] pid           The reader process ID.
- * \param [in] thread        The reader thread ID.
- * \param [in] bytes_used    The number of last used page in the MVCC-snapshot
- *                           which being read,
- *                           i.e. database file can't shrinked beyond this.
- * \param [in] bytes_retired The total size of the database pages that were
- *                           retired by committed write transactions after
- *                           the reader's MVCC-snapshot,
- *                           i.e. the space which would be freed after
- *                           the Reader releases the MVCC-snapshot
- *                           for reuse by completion read transaction.
- *
- * \returns < 0 on failure, >= 0 on success. \see mdbx_reader_list() */
-typedef int(MDBX_reader_list_func)(void *ctx, int num, int slot, mdbx_pid_t pid,
-                                   mdbx_tid_t thread, uint64_t txnid,
-                                   uint64_t lag, size_t bytes_used,
-                                   size_t bytes_retained) MDBX_CXX17_NOEXCEPT;
-
-/** \brief Enumerate the entries in the reader lock table.
- *
- * \ingroup c_statinfo
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create().
- * \param [in] func    A \ref MDBX_reader_list_func function.
- * \param [in] ctx     An arbitrary context pointer for the enumeration
- *                     function.
- *
- * \returns A non-zero error value on failure and 0 on success,
- * or \ref MDBX_RESULT_TRUE if the reader lock table is empty. */
-LIBMDBX_API int mdbx_reader_list(const MDBX_env *env,
-                                 MDBX_reader_list_func *func, void *ctx);
-
-/** \brief Check for stale entries in the reader lock table.
- * \ingroup c_extra
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create().
- * \param [out] dead   Number of stale slots that were cleared.
- *
- * \returns A non-zero error value on failure and 0 on success,
- * or \ref MDBX_RESULT_TRUE if a dead reader(s) found or mutex was recovered. */
-LIBMDBX_API int mdbx_reader_check(MDBX_env *env, int *dead);
-
-/** \brief Returns a lag of the reading for the given transaction.
- * \ingroup c_statinfo
- *
- * Returns an information for estimate how much given read-only
- * transaction is lagging relative the to actual head.
- * \deprecated Please use \ref mdbx_txn_info() instead.
- *
- * \param [in] txn       A transaction handle returned by \ref mdbx_txn_begin().
- * \param [out] percent  Percentage of page allocation in the database.
- *
- * \returns Number of transactions committed after the given was started for
- *          read, or negative value on failure. */
-MDBX_DEPRECATED LIBMDBX_API int mdbx_txn_straggler(const MDBX_txn *txn,
-                                                   int *percent);
-
-/** \brief Registers the current thread as a reader for the environment.
- * \ingroup c_extra
- *
- * To perform read operations without blocking, a reader slot must be assigned
- * for each thread. However, this assignment requires a short-term lock
- * acquisition which is performed automatically. This function allows you to
- * assign the reader slot in advance and thus avoid capturing the blocker when
- * the read transaction starts firstly from current thread.
- * \see mdbx_thread_unregister()
- *
- * \note Threads are registered automatically the first time a read transaction
- *       starts. Therefore, there is no need to use this function, except in
- *       special cases.
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- *
- * \returns A non-zero error value on failure and 0 on success,
- * or \ref MDBX_RESULT_TRUE if thread is already registered. */
-LIBMDBX_API int mdbx_thread_register(const MDBX_env *env);
-
-/** \brief Unregisters the current thread as a reader for the environment.
- * \ingroup c_extra
- *
- * To perform read operations without blocking, a reader slot must be assigned
- * for each thread. However, the assigned reader slot will remain occupied until
- * the thread ends or the environment closes. This function allows you to
- * explicitly release the assigned reader slot.
- * \see mdbx_thread_register()
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- *
- * \returns A non-zero error value on failure and 0 on success, or
- * \ref MDBX_RESULT_TRUE if thread is not registered or already unregistered. */
-LIBMDBX_API int mdbx_thread_unregister(const MDBX_env *env);
-
-/** \brief A Handle-Slow-Readers callback function to resolve database
- * full/overflow issue due to a reader(s) which prevents the old data from being
- * recycled.
- * \ingroup c_err
- *
- * Read transactions prevent reuse of pages freed by newer write transactions,
- * thus the database can grow quickly. This callback will be called when there
- * is not enough space in the database (i.e. before increasing the database size
- * or before \ref MDBX_MAP_FULL error) and thus can be used to resolve issues
- * with a "long-lived" read transactions.
- * \see long-lived-read
- *
- * Using this callback you can choose how to resolve the situation:
- *   - abort the write transaction with an error;
- *   - wait for the read transaction(s) to complete;
- *   - notify a thread performing a long-lived read transaction
- *     and wait for an effect;
- *   - kill the thread or whole process that performs the long-lived read
- *     transaction;
- *
- * Depending on the arguments and needs, your implementation may wait,
- * terminate a process or thread that is performing a long read, or perform
- * some other action. In doing so it is important that the returned code always
- * corresponds to the performed action.
- *
- * \param [in] env     An environment handle returned by \ref mdbx_env_create().
- * \param [in] txn     The current write transaction which internally at
- *                     the \ref MDBX_MAP_FULL condition.
- * \param [in] pid     A pid of the reader process.
- * \param [in] tid     A thread_id of the reader thread.
- * \param [in] laggard An oldest read transaction number on which stalled.
- * \param [in] gap     A lag from the last committed txn.
- * \param [in] space   A space that actually become available for reuse after
- *                     this reader finished. The callback function can take
- *                     this value into account to evaluate the impact that
- *                     a long-running transaction has.
- * \param [in] retry   A retry number starting from 0.
- *                     If callback has returned 0 at least once, then at end
- *                     of current handling loop the callback function will be
- *                     called additionally with negative value to notify about
- *                     the end of loop. The callback function can use this value
- *                     to implement timeout logic while waiting for readers.
- *
- * \returns The RETURN CODE determines the further actions libmdbx and must
- *          match the action which was executed by the callback:
- *
- * \retval -2 or less  An error condition and the reader was not killed.
- *
- * \retval -1          The callback was unable to solve the problem and
- *                     agreed on \ref MDBX_MAP_FULL error;
- *                     libmdbx should increase the database size or
- *                     return \ref MDBX_MAP_FULL error.
- *
- * \retval 0 (zero)    The callback solved the problem or just waited for
- *                     a while, libmdbx should rescan the reader lock table and
- *                     retry. This also includes a situation when corresponding
- *                     transaction terminated in normal way by
- *                     \ref mdbx_txn_abort() or \ref mdbx_txn_reset(),
- *                     and my be restarted. I.e. reader slot don't needed
- *                     to be cleaned from transaction.
- *
- * \retval 1           Transaction aborted asynchronous and reader slot
- *                     should be cleared immediately, i.e. read transaction
- *                     will not continue but \ref mdbx_txn_abort()
- *                     or \ref mdbx_txn_reset() will be called later.
- *
- * \retval 2 or great  The reader process was terminated or killed,
- *                     and libmdbx should entirely reset reader registration.
- *
- * \see mdbx_env_set_hsr() \see mdbx_env_get_hsr()
- */
-typedef int(MDBX_hsr_func)(const MDBX_env *env, const MDBX_txn *txn,
-                           mdbx_pid_t pid, mdbx_tid_t tid, uint64_t laggard,
-                           unsigned gap, size_t space,
-                           int retry) MDBX_CXX17_NOEXCEPT;
-
-/** \brief Sets a Handle-Slow-Readers callback to resolve database full/overflow
- * issue due to a reader(s) which prevents the old data from being recycled.
- * \ingroup c_err
- *
- * The callback will only be triggered when the database is full due to a
- * reader(s) prevents the old data from being recycled.
- *
- * \see mdbx_env_get_hsr()
- * \see long-lived-read
- *
- * \param [in] env             An environment handle returned
- *                             by \ref mdbx_env_create().
- * \param [in] hsr_callback    A \ref MDBX_hsr_func function
- *                             or NULL to disable.
- *
- * \returns A non-zero error value on failure and 0 on success. */
-LIBMDBX_API int mdbx_env_set_hsr(MDBX_env *env, MDBX_hsr_func *hsr_callback);
-
-/** \brief Gets current Handle-Slow-Readers callback used to resolve database
- * full/overflow issue due to a reader(s) which prevents the old data from being
- * recycled.
- * \see mdbx_env_set_hsr()
- *
- * \param [in] env   An environment handle returned by \ref mdbx_env_create().
- *
- * \returns A MDBX_hsr_func function or NULL if disabled
- *          or something wrong. */
-MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API MDBX_hsr_func *
-mdbx_env_get_hsr(const MDBX_env *env);
-
-/** \defgroup btree_traversal B-tree Traversal
- * This is internal API for mdbx_chk tool. You should avoid to use it, except
- * some extremal special cases.
- * \ingroup c_extra
- * @{ */
-
-/** \brief Page types for traverse the b-tree.
- * \see mdbx_env_pgwalk() \see MDBX_pgvisitor_func */
-enum MDBX_page_type_t {
-  MDBX_page_broken,
-  MDBX_page_meta,
-  MDBX_page_large,
-  MDBX_page_branch,
-  MDBX_page_leaf,
-  MDBX_page_dupfixed_leaf,
-  MDBX_subpage_leaf,
-  MDBX_subpage_dupfixed_leaf,
-  MDBX_subpage_broken,
-};
-#ifndef __cplusplus
-typedef enum MDBX_page_type_t MDBX_page_type_t;
-#endif
-
-/** \brief Pseudo-name for MainDB */
-#define MDBX_PGWALK_MAIN ((const char *)((ptrdiff_t)0))
-/** \brief Pseudo-name for GarbageCollectorDB */
-#define MDBX_PGWALK_GC ((const char *)((ptrdiff_t)-1))
-/** \brief Pseudo-name for MetaPages */
-#define MDBX_PGWALK_META ((const char *)((ptrdiff_t)-2))
-
-/** \brief Callback function for traverse the b-tree. \see mdbx_env_pgwalk() */
-typedef int MDBX_pgvisitor_func(
-    const uint64_t pgno, const unsigned number, void *const ctx, const int deep,
-    const char *const dbi, const size_t page_size, const MDBX_page_type_t type,
-    const MDBX_error_t err, const size_t nentries, const size_t payload_bytes,
-    const size_t header_bytes, const size_t unused_bytes) MDBX_CXX17_NOEXCEPT;
-
-/** \brief B-tree traversal function. */
-LIBMDBX_API int mdbx_env_pgwalk(MDBX_txn *txn, MDBX_pgvisitor_func *visitor,
-                                void *ctx, bool dont_check_keys_ordering);
-
-/** \brief Open an environment instance using specific meta-page
- * for checking and recovery.
- *
- * This function mostly of internal API for `mdbx_chk` utility and subject to
- * change at any time. Do not use this function to avoid shooting your own
- * leg(s). */
-LIBMDBX_API int mdbx_env_open_for_recovery(MDBX_env *env, const char *pathname,
-                                           unsigned target_meta,
-                                           bool writeable);
-
-/** \brief Turn database to the specified meta-page.
- *
- * This function mostly of internal API for `mdbx_chk` utility and subject to
- * change at any time. Do not use this function to avoid shooting your own
- * leg(s). */
-LIBMDBX_API int mdbx_env_turn_for_recovery(MDBX_env *env, unsigned target_meta);
-
-/** @} B-tree Traversal */
-
-/**** Attribute support functions for Nexenta
- * *******************************************/
-#if defined(MDBX_NEXENTA_ATTRS) || defined(DOXYGEN)
-/** \defgroup nexenta Attribute support functions for Nexenta
- * \ingroup c_crud
- * @{ */
-typedef uint_fast64_t mdbx_attr_t;
-
-/** Store by cursor with attribute.
- *
- * This function stores key/data pairs into the database. The cursor is
- * positioned at the new item, or on failure usually near it.
- *
- * \note Internally based on \ref MDBX_RESERVE feature,
- *       therefore doesn't support \ref MDBX_DUPSORT.
- *
- * \param [in] cursor  A cursor handle returned by \ref mdbx_cursor_open()
- * \param [in] key     The key operated on.
- * \param [in] data    The data operated on.
- * \param [in] attr    The attribute.
- * \param [in] flags   Options for this operation. This parameter must be set
- *                     to 0 or one of the values described here:
- *  - \ref MDBX_CURRENT
- *      Replace the item at the current cursor position. The key parameter
- *      must still be provided, and must match it, otherwise the function
- *      return \ref MDBX_EKEYMISMATCH.
- *
- *  - \ref MDBX_APPEND
- *      Append the given key/data pair to the end of the database. No key
- *      comparisons are performed. This option allows fast bulk loading when
- *      keys are already known to be in the correct order. Loading unsorted
- *      keys with this flag will cause a \ref MDBX_KEYEXIST error.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_EKEYMISMATCH
- * \retval MDBX_MAP_FULL  The database is full, see \ref mdbx_env_set_mapsize().
- * \retval MDBX_TXN_FULL  The transaction has too many dirty pages.
- * \retval MDBX_EACCES    An attempt was made to write in a read-only
- *                        transaction.
- * \retval MDBX_EINVAL    an invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_put_attr(MDBX_cursor *cursor, MDBX_val *key,
-                                     MDBX_val *data, mdbx_attr_t attr,
-                                     MDBX_put_flags_t flags);
-
-/** Store items and attributes into a database.
- *
- * This function stores key/data pairs in the database. The default behavior
- * is to enter the new key/data pair, replacing any previously existing key
- * if duplicates are disallowed.
- *
- * \note Internally based on \ref MDBX_RESERVE feature,
- *       therefore doesn't support \ref MDBX_DUPSORT.
- *
- * \param [in] txn       A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi       A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key       The key to store in the database.
- * \param [in] attr      The attribute to store in the database.
- * \param [in,out] data  The data to store.
- * \param [in] flags     Special options for this operation. This parameter
- *                       must be set to 0 or by bitwise OR'ing together one or
- *                       more of the values described here:
- *  - \ref MDBX_NOOVERWRITE
- *      Enter the new key/data pair only if the key does not already appear
- *      in the database. The function will return \ref MDBX_KEYEXIST if the key
- *      already appears in the database. The data parameter will be set to
- *      point to the existing item.
- *
- *  - \ref MDBX_CURRENT
- *      Update an single existing entry, but not add new ones. The function
- *      will return \ref MDBX_NOTFOUND if the given key not exist in the
- *      database. Or the \ref MDBX_EMULTIVAL in case duplicates for the given
- *     key.
- *
- *  - \ref MDBX_APPEND
- *      Append the given key/data pair to the end of the database. This option
- *      allows fast bulk loading when keys are already known to be in the
- *      correct order. Loading unsorted keys with this flag will cause
- *      a \ref MDBX_EKEYMISMATCH error.
- *
- * \see \ref c_crud_hints "Quick reference for Insert/Update/Delete operations"
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_KEYEXIST
- * \retval MDBX_MAP_FULL  The database is full, see \ref mdbx_env_set_mapsize().
- * \retval MDBX_TXN_FULL  The transaction has too many dirty pages.
- * \retval MDBX_EACCES    An attempt was made to write
- *                        in a read-only transaction.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_put_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key,
-                              MDBX_val *data, mdbx_attr_t attr,
-                              MDBX_put_flags_t flags);
-
-/** Set items attribute from a database.
- *
- * This function stores key/data pairs attribute to the database.
- *
- * \note Internally based on \ref MDBX_RESERVE feature,
- *       therefore doesn't support \ref MDBX_DUPSORT.
- *
- * \param [in] txn   A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi   A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key   The key to search for in the database.
- * \param [in] data  The data to be stored or NULL to save previous value.
- * \param [in] attr  The attribute to be stored.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_NOTFOUND   The key-value pair was not in the database.
- * \retval MDBX_EINVAL     An invalid parameter was specified. */
-LIBMDBX_API int mdbx_set_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key,
-                              MDBX_val *data, mdbx_attr_t attr);
-
-/** Get items attribute from a database cursor.
- *
- * This function retrieves key/data pairs from the database. The address and
- * length of the key are returned in the object to which key refers (except
- * for the case of the \ref MDBX_SET option, in which the key object is
- * unchanged), and the address and length of the data are returned in the object
- * to which data refers.
- * \see mdbx_get()
- *
- * \param [in] cursor    A cursor handle returned by \ref mdbx_cursor_open().
- * \param [in,out] key   The key for a retrieved item.
- * \param [in,out] data  The data of a retrieved item.
- * \param [out] pattr    The pointer to retrieve attribute.
- * \param [in] op        A cursor operation MDBX_cursor_op.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_NOTFOUND  No matching key found.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_cursor_get_attr(MDBX_cursor *cursor, MDBX_val *key,
-                                     MDBX_val *data, mdbx_attr_t *pattr,
-                                     MDBX_cursor_op op);
-
-/** Get items attribute from a database.
- *
- * This function retrieves key/data pairs from the database. The address
- * and length of the data associated with the specified key are returned
- * in the structure to which data refers.
- * If the database supports duplicate keys (see \ref MDBX_DUPSORT) then the
- * first data item for the key will be returned. Retrieval of other
- * items requires the use of \ref mdbx_cursor_get().
- *
- * \note The memory pointed to by the returned values is owned by the
- * database. The caller need not dispose of the memory, and may not
- * modify it in any way. For values returned in a read-only transaction
- * any modification attempts will cause a `SIGSEGV`.
- *
- * \note Values returned from the database are valid only until a
- * subsequent update operation, or the end of the transaction.
- *
- * \param [in] txn       A transaction handle returned by \ref mdbx_txn_begin().
- * \param [in] dbi       A database handle returned by \ref mdbx_dbi_open().
- * \param [in] key       The key to search for in the database.
- * \param [in,out] data  The data corresponding to the key.
- * \param [out] pattr    The pointer to retrieve attribute.
- *
- * \returns A non-zero error value on failure and 0 on success,
- *          some possible errors are:
- * \retval MDBX_NOTFOUND  The key was not in the database.
- * \retval MDBX_EINVAL    An invalid parameter was specified. */
-LIBMDBX_API int mdbx_get_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key,
-                              MDBX_val *data, mdbx_attr_t *pattr);
-/** @} end of Attribute support functions for Nexenta */
-#endif /* MDBX_NEXENTA_ATTRS */
-
-/** @} end of C API */
-
-/*******************************************************************************
- * Workaround for mmaped-lookahead-cross-page-boundary bug
- * in an obsolete versions of Elbrus's libc and kernels. */
-#if defined(__e2k__) && defined(MDBX_E2K_MLHCPB_WORKAROUND) &&                 \
-    MDBX_E2K_MLHCPB_WORKAROUND
-LIBMDBX_API int mdbx_e2k_memcmp_bug_workaround(const void *s1, const void *s2,
-                                               size_t n);
-LIBMDBX_API int mdbx_e2k_strcmp_bug_workaround(const char *s1, const char *s2);
-LIBMDBX_API int mdbx_e2k_strncmp_bug_workaround(const char *s1, const char *s2,
-                                                size_t n);
-LIBMDBX_API size_t mdbx_e2k_strlen_bug_workaround(const char *s);
-LIBMDBX_API size_t mdbx_e2k_strnlen_bug_workaround(const char *s,
-                                                   size_t maxlen);
-#ifdef __cplusplus
-namespace std {
-inline int mdbx_e2k_memcmp_bug_workaround(const void *s1, const void *s2,
-                                          size_t n) {
-  return ::mdbx_e2k_memcmp_bug_workaround(s1, s2, n);
-}
-inline int mdbx_e2k_strcmp_bug_workaround(const char *s1, const char *s2) {
-  return ::mdbx_e2k_strcmp_bug_workaround(s1, s2);
-}
-inline int mdbx_e2k_strncmp_bug_workaround(const char *s1, const char *s2,
-                                           size_t n) {
-  return ::mdbx_e2k_strncmp_bug_workaround(s1, s2, n);
-}
-inline size_t mdbx_e2k_strlen_bug_workaround(const char *s) {
-  return ::mdbx_e2k_strlen_bug_workaround(s);
-}
-inline size_t mdbx_e2k_strnlen_bug_workaround(const char *s, size_t maxlen) {
-  return ::mdbx_e2k_strnlen_bug_workaround(s, maxlen);
-}
-} // namespace std
-#endif /* __cplusplus */
-
-#include <string.h>
-#include <strings.h>
-#undef memcmp
-#define memcmp mdbx_e2k_memcmp_bug_workaround
-#undef bcmp
-#define bcmp mdbx_e2k_memcmp_bug_workaround
-#undef strcmp
-#define strcmp mdbx_e2k_strcmp_bug_workaround
-#undef strncmp
-#define strncmp mdbx_e2k_strncmp_bug_workaround
-#undef strlen
-#define strlen mdbx_e2k_strlen_bug_workaround
-#undef strnlen
-#define strnlen mdbx_e2k_strnlen_bug_workaround
-#endif /* MDBX_E2K_MLHCPB_WORKAROUND */
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#endif /* LIBMDBX_H */
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx.h++ b/plugins/Dbx_mdbx/src/libmdbx/mdbx.h++
deleted file mode 100644
index 5ae3838aeb..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx.h++
+++ /dev/null
@@ -1,4707 +0,0 @@
-/// \file mdbx.h++
-/// \brief The libmdbx C++ API header file (preliminary).
-///
-/// \author Copyright (c) 2020-2021, Leonid Yuriev <leo@yuriev.ru>.
-/// \copyright SPDX-License-Identifier: Apache-2.0
-///
-/// Tested with:
-///  - LCC >= 1.23 (http://www.mcst.ru/lcc),
-///  - GNU C++ >= 4.8,
-///  - clang >= 4.0,
-///  - MSVC >= 19.0 (Visual Studio 2015),
-///    but 19.2x could hang due optimizer bug.
-///
-
-#pragma once
-
-#if (!defined(__cplusplus) || __cplusplus < 201103L) &&                        \
-    !(defined(                                                                 \
-          _MSC_VER) /* MSVC is mad and don't define __cplusplus properly */    \
-      && _MSC_VER == 1900)
-#error "C++11 or better is required"
-#endif
-
-#if (defined(_WIN32) || defined(_WIN64)) && MDBX_AVOID_CRT
-#error "CRT is required for C++ API, the MDBX_AVOID_CRT option must be disabled"
-#endif /* Windows */
-
-#ifndef __has_include
-#define __has_include(header) (0)
-#endif /* __has_include */
-
-#if __has_include(<version>)
-#include <version>
-#endif /* <version> */
-
-/* Disable min/max macros from C' headers */
-#ifndef NOMINMAX
-#define NOMINMAX
-#endif
-
-#include <algorithm>   // for std::min/max
-#include <cassert>     // for assert()
-#include <cstring>     // for std::strlen, str:memcmp
-#include <exception>   // for std::exception_ptr
-#include <ostream>     // for std::ostream
-#include <sstream>     // for std::ostringstream
-#include <stdexcept>   // for std::invalid_argument
-#include <string>      // for std::string
-#include <type_traits> // for std::is_pod<>, etc.
-#include <vector>      // for std::vector<> as template args
-
-// Unused for now
-// #if defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
-// #include <bit>
-// #endif
-
-#if defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
-#include <memory_resource>
-#endif
-
-#if defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L
-#include <string_view>
-#endif
-
-#if defined(__cpp_lib_filesystem) && __cpp_lib_filesystem >= 201703L
-#include <filesystem>
-#endif
-
-#include "mdbx.h"
-
-#if defined(DOXYGEN) ||                                                        \
-    defined(__cpp_constexpr) && __cpp_constexpr >= 201603L &&                  \
-        ((defined(_MSC_VER) && _MSC_VER >= 1915) ||                            \
-         (defined(__clang__) && __clang_major__ > 5) ||                        \
-         (defined(__GNUC__) && __GNUC__ > 7) ||                                \
-         (!defined(__GNUC__) && !defined(__clang__) && !defined(_MSC_VER)))
-#define MDBX_CXX17_CONSTEXPR constexpr
-#else
-#define MDBX_CXX17_CONSTEXPR inline
-#endif /* MDBX_CXX17_CONSTEXPR */
-
-#if defined(DOXYGEN) || defined(__cpp_lib_is_constant_evaluated) &&            \
-                            __cpp_lib_is_constant_evaluated >= 201811L &&      \
-                            defined(__cpp_lib_constexpr_string) &&             \
-                            __cpp_lib_constexpr_string >= 201907L
-#define MDBX_CXX20_CONSTEXPR constexpr
-#else
-#define MDBX_CXX20_CONSTEXPR inline
-#endif /* MDBX_CXX20_CONSTEXPR */
-
-#if defined(CONSTEXPR_ASSERT)
-#define MDBX_CONSTEXPR_ASSERT(expr) CONSTEXPR_ASSERT(expr)
-#elif defined NDEBUG
-#define MDBX_CONSTEXPR_ASSERT(expr) void(0)
-#else
-#define MDBX_CONSTEXPR_ASSERT(expr)                                            \
-  ((expr) ? void(0) : [] { assert(!#expr); }())
-#endif /* MDBX_CONSTEXPR_ASSERT */
-
-#ifndef MDBX_LIKELY
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__GNUC__) || __has_builtin(__builtin_expect)) &&                  \
-        !defined(__COVERITY__)
-#define MDBX_LIKELY(cond) __builtin_expect(!!(cond), 1)
-#else
-#define MDBX_LIKELY(x) (x)
-#endif
-#endif /* MDBX_LIKELY */
-
-#ifndef MDBX_UNLIKELY
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__GNUC__) || __has_builtin(__builtin_expect)) &&                  \
-        !defined(__COVERITY__)
-#define MDBX_UNLIKELY(cond) __builtin_expect(!!(cond), 0)
-#else
-#define MDBX_UNLIKELY(x) (x)
-#endif
-#endif /* MDBX_UNLIKELY */
-
-#if defined(DOXYGEN) ||                                                        \
-    (__has_cpp_attribute(fallthrough) &&                                       \
-     (!defined(__clang__) || __clang__ > 4)) ||                                \
-    __cplusplus >= 201703L
-#define MDBX_CXX17_FALLTHROUGH [[fallthrough]]
-#else
-#define MDBX_CXX17_FALLTHROUGH
-#endif /* MDBX_CXX17_FALLTHROUGH */
-
-#if defined(DOXYGEN) || __has_cpp_attribute(likely)
-#define MDBX_CXX20_LIKELY [[likely]]
-#else
-#define MDBX_CXX20_LIKELY
-#endif /* MDBX_CXX20_LIKELY */
-
-#ifndef MDBX_CXX20_UNLIKELY
-#if defined(DOXYGEN) || __has_cpp_attribute(unlikely)
-#define MDBX_CXX20_UNLIKELY [[unlikely]]
-#else
-#define MDBX_CXX20_UNLIKELY
-#endif
-#endif /* MDBX_CXX20_UNLIKELY */
-
-#ifdef _MSC_VER
-#pragma warning(push, 4)
-#pragma warning(disable : 4251) /* 'std::FOO' needs to have dll-interface to   \
-                                   be used by clients of 'mdbx::BAR' */
-#pragma warning(disable : 4275) /* non dll-interface 'std::FOO' used as        \
-                                   base for dll-interface 'mdbx::BAR' */
-/* MSVC is mad and can generate this warning for its own intermediate
- * automatically generated code, which becomes unreachable after some kinds of
- * optimization (copy elision, etc). */
-#pragma warning(disable : 4702) /* unreachable code */
-#endif                          /* _MSC_VER (warnings) */
-
-//------------------------------------------------------------------------------
-/// \defgroup cxx_api C++ API
-/// @{
-
-namespace mdbx {
-
-// Functions whose signature depends on the `mdbx::byte` type
-// must be strictly defined as inline!
-#if defined(DOXYGEN) || (defined(__cpp_char8_t) && __cpp_char8_t >= 201811)
-// Wanna using a non-aliasing type to release more power of an optimizer.
-using byte = char8_t;
-#else
-// Wanna not using std::byte since it doesn't add features,
-// but add inconvenient restrictions.
-using byte = unsigned char;
-#endif /* __cpp_char8_t >= 201811*/
-
-/// \copydoc MDBX_version_info
-using version_info = ::MDBX_version_info;
-/// \brief Returns libmdbx version information.
-MDBX_CXX11_CONSTEXPR const version_info &get_version() noexcept;
-/// \copydoc MDBX_build_info
-using build_info = ::MDBX_build_info;
-/// \brief Returns libmdbx build information.
-MDBX_CXX11_CONSTEXPR const build_info &get_build() noexcept;
-
-/// \brief constexpr-compatible strlen().
-static MDBX_CXX17_CONSTEXPR size_t strlen(const char *c_str) noexcept;
-
-struct slice;
-class env;
-class env_managed;
-class txn;
-class txn_managed;
-class cursor;
-class cursor_managed;
-
-/// \brief Legacy default allocator
-/// but it is recommended to use \ref polymorphic_allocator.
-using legacy_allocator = ::std::string::allocator_type;
-
-#if defined(DOXYGEN) ||                                                        \
-    defined(__cpp_lib_memory_resource) && __cpp_lib_memory_resource >= 201603L
-/// \brief Default polymorphic allocator for modern code.
-using polymorphic_allocator = ::std::pmr::string::allocator_type;
-#endif /* __cpp_lib_memory_resource >= 201603L */
-
-/// \brief Default singe-byte string.
-template <class ALLOCATOR = legacy_allocator>
-using string = ::std::basic_string<char, ::std::char_traits<char>, ALLOCATOR>;
-
-using filehandle = ::mdbx_filehandle_t;
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_filesystem) && __cpp_lib_filesystem >= 201703L &&       \
-     (!defined(__MAC_OS_X_VERSION_MIN_REQUIRED) ||                             \
-      __MAC_OS_X_VERSION_MIN_REQUIRED >= 101500))
-#define MDBX_STD_FILESYSTEM_PATH
-using path = ::std::filesystem::path;
-#elif defined(_WIN32) || defined(_WIN64)
-using path = ::std::wstring;
-#else
-using path = ::std::string;
-#endif
-
-/// \brief Transfers C++ exceptions thru C callbacks.
-/// \details Implements saving exceptions before returning
-/// from an C++'s environment to the intermediate C code and re-throwing after
-/// returning from C to the C++'s environment.
-class LIBMDBX_API_TYPE exception_thunk {
-  ::std::exception_ptr captured_;
-
-public:
-  exception_thunk() noexcept = default;
-  exception_thunk(const exception_thunk &) = delete;
-  exception_thunk(exception_thunk &&) = delete;
-  exception_thunk &operator=(const exception_thunk &) = delete;
-  exception_thunk &operator=(exception_thunk &&) = delete;
-  inline bool is_clean() const noexcept;
-  inline void capture() noexcept;
-  inline void rethrow_captured() const;
-};
-
-/// \brief Implements error information and throwing corresponding exceptions.
-class LIBMDBX_API_TYPE error {
-  MDBX_error_t code_;
-  inline error &operator=(MDBX_error_t error_code) noexcept;
-
-public:
-  MDBX_CXX11_CONSTEXPR error(MDBX_error_t error_code) noexcept;
-  error(const error &) = default;
-  error(error &&) = default;
-  error &operator=(const error &) = default;
-  error &operator=(error &&) = default;
-
-  MDBX_CXX11_CONSTEXPR friend bool operator==(const error &a,
-                                              const error &b) noexcept;
-  MDBX_CXX11_CONSTEXPR friend bool operator!=(const error &a,
-                                              const error &b) noexcept;
-
-  MDBX_CXX11_CONSTEXPR bool is_success() const noexcept;
-  MDBX_CXX11_CONSTEXPR bool is_result_true() const noexcept;
-  MDBX_CXX11_CONSTEXPR bool is_result_false() const noexcept;
-  MDBX_CXX11_CONSTEXPR bool is_failure() const noexcept;
-
-  /// \brief Returns error code.
-  MDBX_CXX11_CONSTEXPR MDBX_error_t code() const noexcept;
-
-  /// \brief Returns message for MDBX's errors only and "SYSTEM" for others.
-  const char *what() const noexcept;
-
-  /// \brief Returns message for any errors.
-  ::std::string message() const;
-
-  /// \brief Returns true for MDBX's errors.
-  MDBX_CXX11_CONSTEXPR bool is_mdbx_error() const noexcept;
-  /// \brief Panics on unrecoverable errors inside destructors etc.
-  [[noreturn]] void panic(const char *context_where_when,
-                          const char *func_who_what) const noexcept;
-  [[noreturn]] void throw_exception() const;
-  [[noreturn]] static inline void throw_exception(int error_code);
-  inline void throw_on_failure() const;
-  inline void success_or_throw() const;
-  inline void success_or_throw(const exception_thunk &) const;
-  inline void panic_on_failure(const char *context_where,
-                               const char *func_who) const noexcept;
-  inline void success_or_panic(const char *context_where,
-                               const char *func_who) const noexcept;
-  static inline void throw_on_nullptr(const void *ptr, MDBX_error_t error_code);
-  static inline void success_or_throw(MDBX_error_t error_code);
-  static void success_or_throw(int error_code) {
-    success_or_throw(static_cast<MDBX_error_t>(error_code));
-  }
-  static inline void throw_on_failure(int error_code);
-  static inline bool boolean_or_throw(int error_code);
-  static inline void success_or_throw(int error_code, const exception_thunk &);
-  static inline void panic_on_failure(int error_code, const char *context_where,
-                                      const char *func_who) noexcept;
-  static inline void success_or_panic(int error_code, const char *context_where,
-                                      const char *func_who) noexcept;
-};
-
-/// \brief Base class for all libmdbx's exceptions that are corresponds
-/// to libmdbx errors.
-///
-/// \see MDBX_error_t
-class LIBMDBX_API_TYPE exception : public ::std::runtime_error {
-  using base = ::std::runtime_error;
-  ::mdbx::error error_;
-
-public:
-  exception(const ::mdbx::error &) noexcept;
-  exception(const exception &) = default;
-  exception(exception &&) = default;
-  exception &operator=(const exception &) = default;
-  exception &operator=(exception &&) = default;
-  virtual ~exception() noexcept;
-  const mdbx::error error() const noexcept { return error_; }
-};
-
-/// \brief Fatal exception that lead termination anyway
-/// in dangerous unrecoverable cases.
-class LIBMDBX_API_TYPE fatal : public exception {
-  using base = exception;
-
-public:
-  fatal(const ::mdbx::error &) noexcept;
-  fatal(const exception &src) noexcept : fatal(src.error()) {}
-  fatal(exception &&src) noexcept : fatal(src.error()) {}
-  fatal(const fatal &src) noexcept : fatal(src.error()) {}
-  fatal(fatal &&src) noexcept : fatal(src.error()) {}
-  fatal &operator=(fatal &&) = default;
-  fatal &operator=(const fatal &) = default;
-  virtual ~fatal() noexcept;
-};
-
-#define MDBX_DECLARE_EXCEPTION(NAME)                                           \
-  struct LIBMDBX_API_TYPE NAME : public exception {                            \
-    NAME(const ::mdbx::error &);                                               \
-    virtual ~NAME() noexcept;                                                  \
-  }
-MDBX_DECLARE_EXCEPTION(bad_map_id);
-MDBX_DECLARE_EXCEPTION(bad_transaction);
-MDBX_DECLARE_EXCEPTION(bad_value_size);
-MDBX_DECLARE_EXCEPTION(db_corrupted);
-MDBX_DECLARE_EXCEPTION(db_full);
-MDBX_DECLARE_EXCEPTION(db_invalid);
-MDBX_DECLARE_EXCEPTION(db_too_large);
-MDBX_DECLARE_EXCEPTION(db_unable_extend);
-MDBX_DECLARE_EXCEPTION(db_version_mismatch);
-MDBX_DECLARE_EXCEPTION(db_wanna_write_for_recovery);
-MDBX_DECLARE_EXCEPTION(incompatible_operation);
-MDBX_DECLARE_EXCEPTION(internal_page_full);
-MDBX_DECLARE_EXCEPTION(internal_problem);
-MDBX_DECLARE_EXCEPTION(key_exists);
-MDBX_DECLARE_EXCEPTION(key_mismatch);
-MDBX_DECLARE_EXCEPTION(max_maps_reached);
-MDBX_DECLARE_EXCEPTION(max_readers_reached);
-MDBX_DECLARE_EXCEPTION(multivalue);
-MDBX_DECLARE_EXCEPTION(no_data);
-MDBX_DECLARE_EXCEPTION(not_found);
-MDBX_DECLARE_EXCEPTION(operation_not_permitted);
-MDBX_DECLARE_EXCEPTION(permission_denied_or_not_writeable);
-MDBX_DECLARE_EXCEPTION(reader_slot_busy);
-MDBX_DECLARE_EXCEPTION(remote_media);
-MDBX_DECLARE_EXCEPTION(something_busy);
-MDBX_DECLARE_EXCEPTION(thread_mismatch);
-MDBX_DECLARE_EXCEPTION(transaction_full);
-MDBX_DECLARE_EXCEPTION(transaction_overlapping);
-#undef MDBX_DECLARE_EXCEPTION
-
-[[noreturn]] LIBMDBX_API void throw_too_small_target_buffer();
-[[noreturn]] LIBMDBX_API void throw_max_length_exceeded();
-[[noreturn]] LIBMDBX_API void throw_out_range();
-MDBX_CXX14_CONSTEXPR size_t check_length(size_t bytes);
-
-//------------------------------------------------------------------------------
-
-/// \brief References a data located outside the slice.
-///
-/// The `slice` is similar in many ways to `std::string_view`, but it
-/// implements specific capabilities and manipulates with bytes but
-/// not a characters.
-///
-/// \copydetails MDBX_val
-struct LIBMDBX_API_TYPE slice : public ::MDBX_val {
-  /// \todo slice& operator<<(slice&, ...) for reading
-  /// \todo key-to-value (parse/unpack) functions
-  /// \todo template<class X> key(X); for decoding keys while reading
-
-  enum { max_length = MDBX_MAXDATASIZE };
-
-  /// \brief Create an empty slice.
-  MDBX_CXX11_CONSTEXPR slice() noexcept;
-
-  /// \brief Create a slice that refers to [0,bytes-1] of memory bytes pointed
-  /// by ptr.
-  MDBX_CXX14_CONSTEXPR slice(const void *ptr, size_t bytes);
-
-  /// \brief Create a slice that refers to [begin,end] of memory bytes.
-  MDBX_CXX14_CONSTEXPR slice(const void *begin, const void *end);
-
-  /// \brief Create a slice that refers to text[0,strlen(text)-1].
-  template <size_t SIZE>
-  MDBX_CXX14_CONSTEXPR slice(const char (&text)[SIZE]) noexcept
-      : slice(text, SIZE - 1) {
-    MDBX_CONSTEXPR_ASSERT(SIZE > 0 && text[SIZE - 1] == '\0');
-  }
-  /// \brief Create a slice that refers to c_str[0,strlen(c_str)-1].
-  explicit MDBX_CXX17_CONSTEXPR slice(const char *c_str);
-
-  /// \brief Create a slice that refers to the contents of "str".
-  /* 'explicit' to avoid reference to the temporary std::string instance */
-  template <class C, class T, class A>
-  explicit MDBX_CXX20_CONSTEXPR slice(const ::std::basic_string<C, T, A> &str)
-      : slice(str.data(), str.length() * sizeof(C)) {}
-
-  MDBX_CXX14_CONSTEXPR slice(const MDBX_val &src);
-  MDBX_CXX11_CONSTEXPR slice(const slice &) noexcept = default;
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  /// \brief Create a slice that refers to the same contents as "sv"
-  template <class C, class T>
-  explicit MDBX_CXX14_CONSTEXPR slice(const ::std::basic_string_view<C, T> &sv)
-      : slice(sv.data(), sv.data() + sv.length()) {}
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  inline slice(MDBX_val &&src);
-  inline slice(slice &&src) noexcept;
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  slice(::std::basic_string_view<C, T> &&sv) : slice(sv) {
-    sv = {};
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  template <size_t SIZE>
-  static MDBX_CXX14_CONSTEXPR slice wrap(const char (&text)[SIZE]) {
-    return slice(text);
-  }
-
-  template <typename POD>
-  MDBX_CXX14_CONSTEXPR static slice wrap(const POD &pod) {
-    static_assert(::std::is_standard_layout<POD>::value &&
-                      !std::is_pointer<POD>::value,
-                  "Must be a standard layout type!");
-    return slice(&pod, sizeof(pod));
-  }
-
-  inline slice &assign(const void *ptr, size_t bytes);
-  inline slice &assign(const slice &src) noexcept;
-  inline slice &assign(const ::MDBX_val &src);
-  inline slice &assign(slice &&src) noexcept;
-  inline slice &assign(::MDBX_val &&src);
-  inline slice &assign(const void *begin, const void *end);
-  template <class C, class T, class A>
-  slice &assign(const ::std::basic_string<C, T, A> &str) {
-    return assign(str.data(), str.length() * sizeof(C));
-  }
-  inline slice &assign(const char *c_str);
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  slice &assign(const ::std::basic_string_view<C, T> &view) {
-    return assign(view.begin(), view.end());
-  }
-  template <class C, class T>
-  slice &assign(::std::basic_string_view<C, T> &&view) {
-    assign(view);
-    view = {};
-    return *this;
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  slice &operator=(const slice &) noexcept = default;
-  inline slice &operator=(slice &&src) noexcept;
-  inline slice &operator=(::MDBX_val &&src);
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  slice &operator=(const ::std::basic_string_view<C, T> &view) {
-    return assign(view);
-  }
-  template <class C, class T>
-  slice &operator=(::std::basic_string_view<C, T> &&view) {
-    return assign(view);
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  template <class C = char, class T = ::std::char_traits<C>,
-            class A = legacy_allocator>
-  MDBX_CXX20_CONSTEXPR ::std::basic_string<C, T, A>
-  string(const A &allocator = A()) const {
-    static_assert(sizeof(C) == 1, "Must be single byte characters");
-    return ::std::basic_string<C, T, A>(char_ptr(), length(), allocator);
-  }
-
-  template <class C, class T, class A>
-  MDBX_CXX20_CONSTEXPR operator ::std::basic_string<C, T, A>() const {
-    return this->string<C, T, A>();
-  }
-
-  /// \brief Fills the buffer by hexadecimal data dump of slice content.
-  /// \throws std::length_error if given buffer is too small.
-  char *to_hex(char *dest, size_t dest_size, bool uppercase = false,
-               unsigned wrap_width = 0) const;
-
-  /// \brief Returns the buffer size in bytes needed for hexadecimal data dump
-  /// of slice content.
-  MDBX_CXX11_CONSTEXPR size_t
-  to_hex_bytes(unsigned wrap_width = 0) const noexcept {
-    const size_t bytes = length() << 1;
-    return wrap_width ? bytes + bytes / wrap_width : bytes;
-  }
-
-  /// \brief Fills the buffer with data converted from hexadecimal dump
-  /// from slice content.
-  /// \throws std::length_error if given buffer is too small.
-  byte *from_hex(byte *dest, size_t dest_size,
-                 bool ignore_spaces = false) const;
-
-  /// \brief Returns the buffer size in bytes needed for conversion
-  /// hexadecimal dump from slice content to data.
-  MDBX_CXX11_CONSTEXPR size_t from_hex_bytes() const noexcept {
-    return length() >> 1;
-  }
-
-  /// \brief Fills the buffer by [Base58](https://en.wikipedia.org/wiki/Base58)
-  /// data dump of slice content.
-  /// \throws std::length_error if given buffer is too small.
-  char *to_base58(char *dest, size_t dest_size, unsigned wrap_width = 0) const;
-
-  /// \brief Returns the buffer size in bytes needed for
-  /// [Base58](https://en.wikipedia.org/wiki/Base58) data dump of slice content.
-  MDBX_CXX11_CONSTEXPR size_t
-  to_base58_bytes(unsigned wrap_width = 0) const noexcept {
-    const size_t bytes = length() / 8 * 11 + (length() % 8 * 43 + 31) / 32;
-    return wrap_width ? bytes + bytes / wrap_width : bytes;
-  }
-
-  /// \brief Fills the buffer with data converted from
-  /// [Base58](https://en.wikipedia.org/wiki/Base58) dump from slice content.
-  /// \throws std::length_error if given buffer is too small.
-  byte *from_base58(byte *dest, size_t dest_size,
-                    bool ignore_spaces = false) const;
-
-  /// \brief Returns the buffer size in bytes needed for conversion
-  /// [Base58](https://en.wikipedia.org/wiki/Base58) dump to data.
-  MDBX_CXX11_CONSTEXPR size_t from_base58_bytes() const noexcept {
-    return length() / 11 * 8 + length() % 11 * 32 / 43;
-  }
-
-  /// \brief Fills the buffer by [Base64](https://en.wikipedia.org/wiki/Base64)
-  /// data dump.
-  /// \throws std::length_error if given buffer is too small.
-  char *to_base64(char *dest, size_t dest_size, unsigned wrap_width = 0) const;
-
-  /// \brief Returns the buffer size in bytes needed for
-  /// [Base64](https://en.wikipedia.org/wiki/Base64) data dump.
-  MDBX_CXX11_CONSTEXPR size_t
-  to_base64_bytes(unsigned wrap_width = 0) const noexcept {
-    const size_t bytes = (length() + 2) / 3 * 4;
-    return wrap_width ? bytes + bytes / wrap_width : bytes;
-  }
-
-  /// \brief Fills the buffer with data converted from
-  /// [Base64](https://en.wikipedia.org/wiki/Base64) dump.
-  /// \throws std::length_error if given buffer is too small.
-  byte *from_base64(byte *dest, size_t dest_size,
-                    bool ignore_spaces = false) const;
-
-  /// \brief Returns the buffer size in bytes needed for conversion
-  /// [Base64](https://en.wikipedia.org/wiki/Base64) dump to data.
-  MDBX_CXX11_CONSTEXPR size_t from_base64_bytes() const noexcept {
-    return (length() + 3) / 4 * 3;
-  }
-
-  /// \brief Returns a string with a hexadecimal dump of the slice content.
-  template <class ALLOCATOR = legacy_allocator>
-  inline ::mdbx::string<ALLOCATOR>
-  hex_encode(bool uppercase = false,
-             const ALLOCATOR &allocator = ALLOCATOR()) const;
-
-  /// \brief Decodes hexadecimal dump from the slice content into returned data
-  /// string.
-  template <class ALLOCATOR = legacy_allocator>
-  inline ::mdbx::string<ALLOCATOR>
-  hex_decode(const ALLOCATOR &allocator = ALLOCATOR()) const;
-
-  /// \brief Returns a string with a
-  /// [Base58](https://en.wikipedia.org/wiki/Base58) dump of the slice content.
-  template <class ALLOCATOR = legacy_allocator>
-  inline ::mdbx::string<ALLOCATOR>
-  base58_encode(const ALLOCATOR &allocator = ALLOCATOR()) const;
-
-  /// \brief Decodes [Base58](https://en.wikipedia.org/wiki/Base58) dump
-  /// from the slice content into returned data string.
-  template <class ALLOCATOR = legacy_allocator>
-  inline ::mdbx::string<ALLOCATOR>
-  base58_decode(const ALLOCATOR &allocator = ALLOCATOR()) const;
-
-  /// \brief Returns a string with a
-  /// [Base64](https://en.wikipedia.org/wiki/Base64) dump of the slice content.
-  template <class ALLOCATOR = legacy_allocator>
-  inline ::mdbx::string<ALLOCATOR>
-  base64_encode(const ALLOCATOR &allocator = ALLOCATOR()) const;
-
-  /// \brief Decodes [Base64](https://en.wikipedia.org/wiki/Base64) dump
-  /// from the slice content into returned data string.
-  template <class ALLOCATOR = legacy_allocator>
-  inline ::mdbx::string<ALLOCATOR>
-  base64_decode(const ALLOCATOR &allocator = ALLOCATOR()) const;
-
-  /// \brief Checks whether the content of the slice is printable.
-  /// \param [in] disable_utf8 By default if `disable_utf8` is `false` function
-  /// checks that content bytes are printable ASCII-7 characters or a valid UTF8
-  /// sequences. Otherwise, if if `disable_utf8` is `true` function checks that
-  /// content bytes are printable extended 8-bit ASCII codes.
-  MDBX_NOTHROW_PURE_FUNCTION bool
-  is_printable(bool disable_utf8 = false) const noexcept;
-
-  /// \brief Checks whether the content of the slice is a hexadecimal dump.
-  /// \param [in] ignore_spaces If `true` function will skips spaces surrounding
-  /// (before, between and after) a encoded bytes. However, spaces should not
-  /// break a pair of characters encoding a single byte.
-  MDBX_NOTHROW_PURE_FUNCTION bool
-  is_hex(bool ignore_spaces = false) const noexcept;
-  MDBX_NOTHROW_PURE_FUNCTION bool
-
-  /// \brief Checks whether the content of the slice is a
-  /// [Base58](https://en.wikipedia.org/wiki/Base58) dump.
-  /// \param [in] ignore_spaces If `true` function will skips spaces surrounding
-  /// (before, between and after) a encoded bytes. However, spaces should not
-  /// break a code group of characters.
-  is_base58(bool ignore_spaces = false) const noexcept;
-  MDBX_NOTHROW_PURE_FUNCTION bool
-
-  /// \brief Checks whether the content of the slice is a
-  /// [Base64](https://en.wikipedia.org/wiki/Base64) dump.
-  /// \param [in] ignore_spaces If `true` function will skips spaces surrounding
-  /// (before, between and after) a encoded bytes. However, spaces should not
-  /// break a code group of characters.
-  is_base64(bool ignore_spaces = false) const noexcept;
-
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  /// \brief Return a string_view that references the same data as this slice.
-  template <class C, class T>
-  MDBX_CXX11_CONSTEXPR explicit
-  operator ::std::basic_string_view<C, T>() const noexcept {
-    static_assert(sizeof(C) == 1, "Must be single byte characters");
-    return ::std::basic_string_view<C, T>(char_ptr(), length());
-  }
-
-  /// \brief Return a string_view that references the same data as this slice.
-  template <class C = char, class T = ::std::char_traits<C>>
-  MDBX_CXX11_CONSTEXPR ::std::basic_string_view<C, T>
-  string_view() const noexcept {
-    static_assert(sizeof(C) == 1, "Must be single byte characters");
-    return ::std::basic_string_view<C, T>(char_ptr(), length());
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  inline void swap(slice &other) noexcept;
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  void swap(::std::basic_string_view<C, T> &view) noexcept {
-    static_assert(sizeof(C) == 1, "Must be single byte characters");
-    const auto temp = ::std::basic_string_view<C, T>(*this);
-    *this = view;
-    view = temp;
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  /// \brief Returns casted to pointer to byte an address of data.
-  MDBX_CXX11_CONSTEXPR const byte *byte_ptr() const noexcept;
-
-  /// \brief Returns casted to pointer to char an address of data.
-  MDBX_CXX11_CONSTEXPR const char *char_ptr() const noexcept;
-
-  /// \brief Return a pointer to the beginning of the referenced data.
-  MDBX_CXX11_CONSTEXPR const void *data() const noexcept;
-
-  /// \brief Returns the number of bytes.
-  MDBX_CXX11_CONSTEXPR size_t length() const noexcept;
-
-  /// \brief Checks whether the slice is empty.
-  MDBX_CXX11_CONSTEXPR bool empty() const noexcept;
-
-  /// \brief Checks whether the slice data pointer is nullptr.
-  MDBX_CXX11_CONSTEXPR bool is_null() const noexcept;
-
-  /// \brief Returns the number of bytes.
-  MDBX_CXX11_CONSTEXPR size_t size() const noexcept;
-
-  /// \brief Returns true if slice is not empty.
-  MDBX_CXX11_CONSTEXPR operator bool() const noexcept;
-
-  /// \brief Depletes content of slice and make it invalid.
-  inline void invalidate() noexcept;
-
-  /// \brief Makes the slice empty and referencing to nothing.
-  inline void clear() noexcept;
-
-  /// \brief Drops the first "n" bytes from this slice.
-  /// \pre REQUIRES: `n <= size()`
-  inline void remove_prefix(size_t n) noexcept;
-
-  /// \brief Drops the last "n" bytes from this slice.
-  /// \pre REQUIRES: `n <= size()`
-  inline void remove_suffix(size_t n) noexcept;
-
-  /// \brief Drops the first "n" bytes from this slice.
-  /// \throws std::out_of_range if `n > size()`
-  inline void safe_remove_prefix(size_t n);
-
-  /// \brief Drops the last "n" bytes from this slice.
-  /// \throws std::out_of_range if `n > size()`
-  inline void safe_remove_suffix(size_t n);
-
-  /// \brief Checks if the data starts with the given prefix.
-  MDBX_NOTHROW_PURE_FUNCTION inline bool
-  starts_with(const slice &prefix) const noexcept;
-
-  /// \brief Checks if the data ends with the given suffix.
-  MDBX_NOTHROW_PURE_FUNCTION inline bool
-  ends_with(const slice &suffix) const noexcept;
-
-  /// \brief Returns the nth byte in the referenced data.
-  /// \pre REQUIRES: `n < size()`
-  inline byte operator[](size_t n) const noexcept;
-
-  /// \brief Returns the nth byte in the referenced data with bounds checking.
-  /// \throws std::out_of_range if `n >= size()`
-  inline byte at(size_t n) const;
-
-  /// \brief Returns the first "n" bytes of the slice.
-  /// \pre REQUIRES: `n <= size()`
-  inline slice head(size_t n) const noexcept;
-
-  /// \brief Returns the last "n" bytes of the slice.
-  /// \pre REQUIRES: `n <= size()`
-  inline slice tail(size_t n) const noexcept;
-
-  /// \brief Returns the middle "n" bytes of the slice.
-  /// \pre REQUIRES: `from + n <= size()`
-  inline slice middle(size_t from, size_t n) const noexcept;
-
-  /// \brief Returns the first "n" bytes of the slice.
-  /// \throws std::out_of_range if `n >= size()`
-  inline slice safe_head(size_t n) const;
-
-  /// \brief Returns the last "n" bytes of the slice.
-  /// \throws std::out_of_range if `n >= size()`
-  inline slice safe_tail(size_t n) const;
-
-  /// \brief Returns the middle "n" bytes of the slice.
-  /// \throws std::out_of_range if `from + n >= size()`
-  inline slice safe_middle(size_t from, size_t n) const;
-
-  /// \brief Returns the hash value of referenced data.
-  /// \attention Function implementation and returned hash values may changed
-  /// version to version, and in future the t1ha3 will be used here. Therefore
-  /// values obtained from this function shouldn't be persisted anywhere.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX14_CONSTEXPR size_t
-  hash_value() const noexcept;
-
-  /// \brief Three-way fast non-lexicographically length-based comparison.
-  /// \return value:
-  ///   == 0 if "a" == "b",
-  ///   <  0 if "a" shorter than "b",
-  ///   >  0 if "a" longer than "b",
-  ///   <  0 if "a" length-equal and lexicographically less than "b",
-  ///   >  0 if "a" length-equal and lexicographically great than "b".
-  MDBX_NOTHROW_PURE_FUNCTION static inline intptr_t
-  compare_fast(const slice &a, const slice &b) noexcept;
-
-  /// \brief Three-way lexicographically comparison.
-  /// \return value:
-  ///   <  0 if "a" <  "b",
-  ///   == 0 if "a" == "b",
-  ///   >  0 if "a" >  "b".
-  MDBX_NOTHROW_PURE_FUNCTION static inline intptr_t
-  compare_lexicographically(const slice &a, const slice &b) noexcept;
-  friend inline bool operator==(const slice &a, const slice &b) noexcept;
-  friend inline bool operator<(const slice &a, const slice &b) noexcept;
-  friend inline bool operator>(const slice &a, const slice &b) noexcept;
-  friend inline bool operator<=(const slice &a, const slice &b) noexcept;
-  friend inline bool operator>=(const slice &a, const slice &b) noexcept;
-  friend inline bool operator!=(const slice &a, const slice &b) noexcept;
-
-  /// \brief Checks the slice is not refers to null address or has zero length.
-  MDBX_CXX11_CONSTEXPR bool is_valid() const noexcept {
-    return !(iov_base == nullptr && iov_len != 0);
-  }
-
-  /// \brief Build an invalid slice which non-zero length and refers to null
-  /// address.
-  MDBX_CXX11_CONSTEXPR static slice invalid() noexcept {
-    return slice(size_t(-1));
-  }
-
-protected:
-  MDBX_CXX11_CONSTEXPR slice(size_t invalid_length) noexcept
-      : ::MDBX_val({nullptr, invalid_length}) {}
-};
-
-//------------------------------------------------------------------------------
-
-/// \brief The chunk of data stored inside the buffer or located outside it.
-template <class ALLOCATOR = legacy_allocator> class buffer {
-  friend class txn;
-  using silo = ::mdbx::string<ALLOCATOR>;
-  silo silo_;
-  ::mdbx::slice slice_;
-
-  void insulate() {
-    assert(is_reference());
-    silo_.assign(slice_.char_ptr(), slice_.length());
-    slice_.iov_base = const_cast<char *>(silo_.data());
-  }
-
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR const byte *
-  silo_begin() const noexcept {
-    return static_cast<const byte *>(static_cast<const void *>(silo_.data()));
-  }
-
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR const byte *
-  silo_end() const noexcept {
-    return silo_begin() + silo_.capacity();
-  }
-
-  struct data_preserver : public exception_thunk {
-    buffer data;
-    data_preserver(ALLOCATOR &allocator) : data(allocator) {}
-    static int callback(void *context, MDBX_val *target, const void *src,
-                        size_t bytes) noexcept;
-    MDBX_CXX11_CONSTEXPR operator MDBX_preserve_func() const noexcept {
-      return callback;
-    }
-    MDBX_CXX11_CONSTEXPR operator const buffer &() const noexcept {
-      return data;
-    }
-    MDBX_CXX11_CONSTEXPR operator buffer &() noexcept { return data; }
-  };
-
-public:
-  /// \todo buffer& operator<<(buffer&, ...) for writing
-  /// \todo buffer& operator>>(buffer&, ...) for reading (delegated to slice)
-  /// \todo template<class X> key(X) for encoding keys while writing
-
-  using allocator_type = ALLOCATOR;
-  enum : size_t {
-    max_length = MDBX_MAXDATASIZE,
-    default_shrink_threshold = 1024
-  };
-
-  /// \brief Returns the associated allocator.
-  MDBX_CXX20_CONSTEXPR allocator_type get_allocator() const {
-    return silo_.get_allocator();
-  }
-
-  /// \brief Checks whether data chunk stored inside the buffer, otherwise
-  /// buffer just refers to data located outside the buffer.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR bool
-  is_freestanding() const noexcept {
-    return size_t(byte_ptr() - silo_begin()) < silo_.capacity();
-  }
-
-  /// \brief Checks whether the buffer just refers to data located outside
-  /// the buffer, rather than stores it.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR bool
-  is_reference() const noexcept {
-    return !is_freestanding();
-  }
-
-  /// \brief Returns the number of bytes that can be held in currently allocated
-  /// storage.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR size_t
-  capacity() const noexcept {
-    return is_freestanding() ? silo_.capacity() : 0;
-  }
-
-  /// \brief Returns the number of bytes that available in currently allocated
-  /// storage ahead the currently beginning of data.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR size_t
-  headroom() const noexcept {
-    return is_freestanding() ? slice_.byte_ptr() - silo_begin() : 0;
-  }
-
-  /// \brief Returns the number of bytes that available in currently allocated
-  /// storage after the currently data end.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR size_t
-  tailroom() const noexcept {
-    return is_freestanding() ? capacity() - headroom() - slice_.length() : 0;
-  }
-
-  /// \brief Returns casted to const pointer to byte an address of data.
-  MDBX_CXX11_CONSTEXPR const byte *byte_ptr() const noexcept {
-    return slice_.byte_ptr();
-  }
-
-  /// \brief Returns casted to pointer to byte an address of data.
-  /// \pre REQUIRES: The buffer should store data chunk, but not referenced to
-  /// an external one.
-  MDBX_CXX11_CONSTEXPR byte *byte_ptr() noexcept {
-    assert(is_freestanding());
-    return const_cast<byte *>(slice_.byte_ptr());
-  }
-
-  /// \brief Returns casted to const pointer to char an address of data.
-  MDBX_CXX11_CONSTEXPR const char *char_ptr() const noexcept {
-    return slice_.char_ptr();
-  }
-
-  /// \brief Returns casted to pointer to char an address of data.
-  /// \pre REQUIRES: The buffer should store data chunk, but not referenced to
-  /// an external one.
-  MDBX_CXX11_CONSTEXPR char *char_ptr() noexcept {
-    assert(is_freestanding());
-    return const_cast<char *>(slice_.char_ptr());
-  }
-
-  /// \brief Return a const pointer to the beginning of the referenced data.
-  MDBX_CXX11_CONSTEXPR const void *data() const noexcept {
-    return slice_.data();
-  }
-
-  /// \brief Return a pointer to the beginning of the referenced data.
-  /// \pre REQUIRES: The buffer should store data chunk, but not referenced to
-  /// an external one.
-  MDBX_CXX11_CONSTEXPR void *data() noexcept {
-    assert(is_freestanding());
-    return const_cast<void *>(slice_.data());
-  }
-
-  /// \brief Returns the number of bytes.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR size_t
-  length() const noexcept {
-    return MDBX_CONSTEXPR_ASSERT(is_reference() ||
-                                 slice_.length() + headroom() ==
-                                     silo_.length()),
-           slice_.length();
-  }
-
-  void make_freestanding() {
-    if (is_reference())
-      insulate();
-  }
-
-  buffer(const ::mdbx::slice &src, bool make_reference,
-         const allocator_type &allocator = allocator_type())
-      : silo_(allocator), slice_(src) {
-    if (!make_reference)
-      insulate();
-  }
-
-  buffer(const buffer &src, bool make_reference,
-         const allocator_type &allocator = allocator_type())
-      : buffer(src.slice_, make_reference, allocator) {}
-
-  buffer(const void *ptr, size_t bytes, bool make_reference,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(ptr, bytes), make_reference, allocator) {}
-
-  template <class C, class T, class A>
-  buffer(const ::std::basic_string<C, T, A> &str, bool make_reference,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(str), make_reference, allocator) {}
-
-  buffer(const char *c_str, bool make_reference,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(c_str), make_reference, allocator) {}
-
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  buffer(const ::std::basic_string_view<C, T> &view, bool make_reference,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(view), make_reference, allocator) {}
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  MDBX_CXX20_CONSTEXPR
-  buffer(const ::mdbx::slice &src,
-         const allocator_type &allocator = allocator_type())
-      : silo_(src.char_ptr(), src.length(), allocator), slice_(silo_) {}
-
-  MDBX_CXX20_CONSTEXPR
-  buffer(const buffer &src, const allocator_type &allocator = allocator_type())
-      : buffer(src.slice_, allocator) {}
-
-  MDBX_CXX20_CONSTEXPR
-  buffer(const void *ptr, size_t bytes,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(ptr, bytes), allocator) {}
-
-  template <class C, class T, class A>
-  MDBX_CXX20_CONSTEXPR
-  buffer(const ::std::basic_string<C, T, A> &str,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(str), allocator) {}
-
-  MDBX_CXX20_CONSTEXPR
-  buffer(const char *c_str, const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(c_str), allocator) {}
-
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  MDBX_CXX20_CONSTEXPR
-  buffer(const ::std::basic_string_view<C, T> &view,
-         const allocator_type &allocator = allocator_type())
-      : buffer(::mdbx::slice(view), allocator) {}
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  inline buffer(size_t head_room, size_t tail_room,
-                const allocator_type &allocator = allocator_type());
-
-  inline buffer(size_t capacity,
-                const allocator_type &allocator = allocator_type());
-
-  inline buffer(size_t head_room, const ::mdbx::slice &src, size_t tail_room,
-                const allocator_type &allocator = allocator_type());
-
-  buffer(size_t head_room, const buffer &src, size_t tail_room,
-         const allocator_type &allocator = allocator_type())
-      : buffer(head_room, src.slice_, tail_room, allocator) {}
-
-  MDBX_CXX20_CONSTEXPR
-  buffer(const allocator_type &allocator = allocator_type()) noexcept
-      : silo_(allocator) {}
-
-  inline buffer(const txn &txn, const ::mdbx::slice &src,
-                const allocator_type &allocator = allocator_type());
-
-  buffer(buffer &&src) noexcept
-      : silo_(::std::move(src.silo_)), slice_(::std::move(src.slice_)) {}
-
-  buffer(silo &&str) noexcept : silo_(::std::move(str)), slice_(silo_) {}
-
-  MDBX_CXX11_CONSTEXPR const ::mdbx::slice &slice() const noexcept {
-    return slice_;
-  }
-
-  MDBX_CXX11_CONSTEXPR operator const ::mdbx::slice &() const noexcept {
-    return slice_;
-  }
-
-  template <typename POD>
-  static buffer wrap(const POD &pod, bool make_reference = false,
-                     const allocator_type &allocator = allocator_type()) {
-    return buffer(::mdbx::slice::wrap(pod), make_reference, allocator);
-  }
-
-  /// \brief Reserves storage.
-  inline void reserve(size_t wanna_headroom, size_t wanna_tailroom,
-                      size_t shrink_threshold = default_shrink_threshold);
-
-  buffer &assign_reference(const void *ptr, size_t bytes) noexcept {
-    silo_.clear();
-    slice_.assign(ptr, bytes);
-    return *this;
-  }
-
-  buffer &assign_freestanding(const void *ptr, size_t bytes) {
-    silo_.assign(static_cast<const typename silo::value_type *>(ptr),
-                 check_length(bytes));
-    slice_.assign(silo_);
-    return *this;
-  }
-
-  void swap(buffer &other)
-#if defined(__cpp_noexcept_function_type) &&                                   \
-    __cpp_noexcept_function_type >= 201510L
-      noexcept(
-          std::allocator_traits<ALLOCATOR>::propagate_on_container_swap::value
-#if defined(__cpp_lib_allocator_traits_is_always_equal) &&                     \
-    __cpp_lib_allocator_traits_is_always_equal >= 201411L
-          || std::allocator_traits<ALLOCATOR>::is_always_equal::value
-#endif /* __cpp_lib_allocator_traits_is_always_equal */
-      )
-#endif /* __cpp_noexcept_function_type */
-          ;
-
-  buffer &assign(buffer &&src)
-#if defined(__cpp_noexcept_function_type) &&                                   \
-    __cpp_noexcept_function_type >= 201510L
-      noexcept(std::allocator_traits<
-                   ALLOCATOR>::propagate_on_container_move_assignment::value
-#if defined(__cpp_lib_allocator_traits_is_always_equal) &&                     \
-    __cpp_lib_allocator_traits_is_always_equal >= 201411L
-               || std::allocator_traits<ALLOCATOR>::is_always_equal::value
-#endif /* __cpp_lib_allocator_traits_is_always_equal */
-      )
-#endif /* __cpp_noexcept_function_type */
-  {
-    silo_.assign(::std::move(src.silo_));
-    slice_.assign(::std::move(src.slice_));
-    return *this;
-  }
-
-  buffer &assign(silo &&src)
-#if defined(__cpp_noexcept_function_type) &&                                   \
-    __cpp_noexcept_function_type >= 201510L
-      noexcept(std::allocator_traits<
-                   ALLOCATOR>::propagate_on_container_move_assignment::value
-#if defined(__cpp_lib_allocator_traits_is_always_equal) &&                     \
-    __cpp_lib_allocator_traits_is_always_equal >= 201411L
-               || std::allocator_traits<ALLOCATOR>::is_always_equal::value
-#endif /* __cpp_lib_allocator_traits_is_always_equal */
-      )
-#endif /* __cpp_noexcept_function_type */
-  {
-    return assign(buffer(::std::move(src)));
-  }
-
-  static buffer clone(const buffer &src,
-                      const allocator_type &allocator = allocator_type()) {
-    return buffer(src.headroom(), src.slice_, src.tailroom(), allocator);
-  }
-
-  buffer &assign(const buffer &src, bool make_reference = false) {
-    return assign(src.slice_, make_reference);
-  }
-
-  buffer &assign(const void *ptr, size_t bytes, bool make_reference = false) {
-    return make_reference ? assign_reference(ptr, bytes)
-                          : assign_freestanding(ptr, bytes);
-  }
-
-  buffer &assign(const ::mdbx::slice &src, bool make_reference = false) {
-    return assign(src.data(), src.length(), make_reference);
-  }
-
-  buffer &assign(const ::MDBX_val &src, bool make_reference = false) {
-    return assign(src.iov_base, src.iov_len, make_reference);
-  }
-
-  buffer &assign(::mdbx::slice &&src, bool make_reference = false) {
-    assign(src.data(), src.length(), make_reference);
-    src.invalidate();
-    return *this;
-  }
-
-  buffer &assign(::MDBX_val &&src, bool make_reference = false) {
-    assign(src.iov_base, src.iov_len, make_reference);
-    src.iov_base = nullptr;
-    return *this;
-  }
-
-  buffer &assign(const void *begin, const void *end,
-                 bool make_reference = false) {
-    return assign(begin,
-                  static_cast<const byte *>(end) -
-                      static_cast<const byte *>(begin),
-                  make_reference);
-  }
-
-  template <class C, class T, class A>
-  buffer &assign(const ::std::basic_string<C, T, A> &str,
-                 bool make_reference = false) {
-    return assign(str.data(), str.length(), make_reference);
-  }
-
-  buffer &assign(const char *c_str, bool make_reference = false) {
-    return assign(c_str, ::mdbx::strlen(c_str), make_reference);
-  }
-
-#if defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L
-  template <class C, class T>
-  buffer &assign(const ::std::basic_string_view<C, T> &view,
-                 bool make_reference = false) {
-    return assign(view.data(), view.length(), make_reference);
-  }
-
-  template <class C, class T>
-  buffer &assign(::std::basic_string_view<C, T> &&view,
-                 bool make_reference = false) {
-    assign(view.data(), view.length(), make_reference);
-    view = {};
-    return *this;
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  buffer &operator=(const buffer &src) { return assign(src); }
-
-  buffer &operator=(buffer &&src) noexcept { return assign(::std::move(src)); }
-
-  buffer &operator=(silo &&src) noexcept { return assign(::std::move(src)); }
-
-  buffer &operator=(const ::mdbx::slice &src) { return assign(src); }
-
-  buffer &operator=(::mdbx::slice &&src) { return assign(::std::move(src)); }
-
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  buffer &operator=(const ::std::basic_string_view<C, T> &view) noexcept {
-    return assign(view);
-  }
-
-  /// \brief Return a string_view that references the data of this buffer.
-  template <class C = char, class T = ::std::char_traits<C>>
-  ::std::basic_string_view<C, T> string_view() const noexcept {
-    return slice_.string_view<C, T>();
-  }
-
-  /// \brief Return a string_view that references the data of this buffer.
-  template <class C, class T>
-  operator ::std::basic_string_view<C, T>() const noexcept {
-    return string_view<C, T>();
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  /// \brief Decodes hexadecimal dump from the given slice to the returned
-  /// buffer.
-  static buffer decode_hex(const ::mdbx::slice &hex,
-                           const allocator_type &allocator = allocator_type()) {
-#if __cplusplus >= 201703L
-    return buffer(hex.hex_decode(allocator));
-#else
-    silo data(hex.hex_decode(allocator));
-    return buffer(::std::move(data));
-#endif
-  }
-
-  /// \brief Returns a buffer with a hexadecimal dump of the given slice.
-  static buffer encode_hex(const ::mdbx::slice &data, bool uppercase = false,
-                           const allocator_type &allocator = allocator_type()) {
-#if __cplusplus >= 201703L
-    return buffer(data.hex_encode(uppercase, allocator));
-#else
-    silo hex(data.hex_encode(uppercase, allocator));
-    return buffer(::std::move(hex));
-#endif
-  }
-
-  /// \brief Decodes [Base58](https://en.wikipedia.org/wiki/Base58) dump from
-  /// the given slice to the returned buffer.
-  static buffer
-  decode_base58(const ::mdbx::slice &base58,
-                const allocator_type &allocator = allocator_type()) {
-#if __cplusplus >= 201703L
-    return buffer(base58.base58_decode(allocator));
-#else
-    silo data(base58.base58_decode(allocator));
-    return buffer(::std::move(data));
-#endif
-  }
-
-  /// \brief Returns a buffer with a
-  /// [Base58](https://en.wikipedia.org/wiki/Base58) dump of the given slice.
-  static buffer
-  encode_base58(const ::mdbx::slice &data,
-                const allocator_type &allocator = allocator_type()) {
-#if __cplusplus >= 201703L
-    return buffer(data.base58_encode(allocator));
-#else
-    silo base58(data.base58_encode(allocator));
-    return buffer(::std::move(base58));
-#endif
-  }
-
-  /// \brief Decodes [Base64](https://en.wikipedia.org/wiki/Base64) dump from
-  /// the given slice to the returned buffer.
-  static buffer
-  decode_base64(const ::mdbx::slice &base64,
-                const allocator_type &allocator = allocator_type()) {
-#if __cplusplus >= 201703L
-    return buffer(base64.base64_decode(allocator));
-#else
-    silo data(base64.base64_decode(allocator));
-    return buffer(::std::move(data));
-#endif
-  }
-
-  /// \brief Returns a buffer with a
-  /// [Base64](https://en.wikipedia.org/wiki/Base64) dump of the given slice.
-  static buffer
-  encode_base64(const ::mdbx::slice &data,
-                const allocator_type &allocator = allocator_type()) {
-#if __cplusplus >= 201703L
-    return buffer(data.base64_encode(allocator));
-#else
-    silo base64(data.base64_encode(allocator));
-    return buffer(::std::move(base64));
-#endif
-  }
-
-  /// \brief Checks whether the string is empty.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR bool empty() const noexcept {
-    return length() == 0;
-  }
-
-  /// \brief Checks whether the data pointer of the buffer is nullptr.
-  MDBX_CXX11_CONSTEXPR bool is_null() const noexcept {
-    return data() == nullptr;
-  }
-
-  /// \brief Returns the number of bytes.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX20_CONSTEXPR size_t size() const noexcept {
-    return length();
-  }
-
-  /// \brief Returns the hash value of the data.
-  /// \attention Function implementation and returned hash values may changed
-  /// version to version, and in future the t1ha3 will be used here. Therefore
-  /// values obtained from this function shouldn't be persisted anywhere.
-  MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX14_CONSTEXPR size_t
-  hash_value() const noexcept {
-    return slice_.hash_value();
-  }
-
-  template <class C = char, class T = ::std::char_traits<C>,
-            class A = legacy_allocator>
-  MDBX_CXX20_CONSTEXPR ::std::basic_string<C, T, A>
-  string(const A &allocator = A()) const {
-    return slice_.string<C, T, A>(allocator);
-  }
-
-  template <class C, class T, class A>
-  MDBX_CXX20_CONSTEXPR operator ::std::basic_string<C, T, A>() const {
-    return this->string<C, T, A>();
-  }
-
-  /// \brief Checks if the data starts with the given prefix.
-  MDBX_NOTHROW_PURE_FUNCTION bool
-  starts_with(const ::mdbx::slice &prefix) const noexcept {
-    return slice_.starts_with(prefix);
-  }
-
-  /// \brief Checks if the data ends with the given suffix.
-  MDBX_NOTHROW_PURE_FUNCTION bool
-  ends_with(const ::mdbx::slice &suffix) const noexcept {
-    return slice_.ends_with(suffix);
-  }
-
-  /// \brief Clears the contents and storage.
-  void clear() noexcept {
-    slice_.clear();
-    silo_.clear();
-  }
-
-  /// \brief Reduces memory usage by freeing unused storage space.
-  void shrink_to_fit(size_t threshold = 64) { reserve(0, 0, threshold); }
-
-  /// \brief Drops the first "n" bytes from the data chunk.
-  /// \pre REQUIRES: `n <= size()`
-  void remove_prefix(size_t n) noexcept { slice_.remove_prefix(n); }
-
-  /// \brief Drops the last "n" bytes from the data chunk.
-  /// \pre REQUIRES: `n <= size()`
-  void remove_suffix(size_t n) noexcept { slice_.remove_suffix(n); }
-
-  /// \brief Drops the first "n" bytes from the data chunk.
-  /// \throws std::out_of_range if `n > size()`
-  void safe_remove_prefix(size_t n) { slice_.safe_remove_prefix(n); }
-
-  /// \brief Drops the last "n" bytes from the data chunk.
-  /// \throws std::out_of_range if `n > size()`
-  void safe_remove_suffix(size_t n) { slice_.safe_remove_suffix(n); }
-
-  /// \brief Accesses the specified byte of data chunk.
-  /// \pre REQUIRES: `n < size()`
-  byte operator[](size_t n) const noexcept { return slice_[n]; }
-
-  /// \brief Accesses the specified byte of data chunk.
-  /// \pre REQUIRES: `n < size()`
-  byte &operator[](size_t n) noexcept {
-    assert(n < size());
-    return byte_ptr()[n];
-  }
-
-  /// \brief Accesses the specified byte of data chunk with bounds checking.
-  /// \throws std::out_of_range if `n >= size()`
-  byte at(size_t n) const { return slice_.at(n); }
-
-  /// \brief Accesses the specified byte of data chunk with bounds checking.
-  /// \throws std::out_of_range if `n >= size()`
-  byte &at(size_t n) {
-    if (MDBX_UNLIKELY(n >= size()))
-      MDBX_CXX20_UNLIKELY throw_out_range();
-    return byte_ptr()[n];
-  }
-
-  /// \brief Returns the first "n" bytes of the data chunk.
-  /// \pre REQUIRES: `n <= size()`
-  ::mdbx::slice head(size_t n) const noexcept { return slice_.head(n); }
-
-  /// \brief Returns the last "n" bytes of the data chunk.
-  /// \pre REQUIRES: `n <= size()`
-  ::mdbx::slice tail(size_t n) const noexcept { return slice_.tail(n); }
-
-  /// \brief Returns the middle "n" bytes of the data chunk.
-  /// \pre REQUIRES: `from + n <= size()`
-  ::mdbx::slice middle(size_t from, size_t n) const noexcept {
-    return slice_.middle(from, n);
-  }
-
-  /// \brief Returns the first "n" bytes of the data chunk.
-  /// \throws std::out_of_range if `n >= size()`
-  ::mdbx::slice safe_head(size_t n) const { return slice_.safe_head(n); }
-
-  /// \brief Returns the last "n" bytes of the data chunk.
-  /// \throws std::out_of_range if `n >= size()`
-  ::mdbx::slice safe_tail(size_t n) const { return slice_.safe_tail(n); }
-
-  /// \brief Returns the middle "n" bytes of the data chunk.
-  /// \throws std::out_of_range if `from + n >= size()`
-  ::mdbx::slice safe_middle(size_t from, size_t n) const {
-    return slice_.safe_middle(from, n);
-  }
-
-  inline buffer &append(const void *src, size_t bytes);
-
-  buffer &append(const ::mdbx::slice &chunk) {
-    return append(chunk.data(), chunk.size());
-  }
-
-  inline buffer &add_header(const void *src, size_t bytes);
-
-  buffer &add_header(const ::mdbx::slice &chunk) {
-    return add_header(chunk.data(), chunk.size());
-  }
-
-  //----------------------------------------------------------------------------
-
-  template <size_t SIZE>
-  static buffer key_from(const char (&text)[SIZE], bool make_reference = true) {
-    return buffer(::mdbx::slice(text), make_reference);
-  }
-
-#if defined(DOXYGEN) ||                                                        \
-    (defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L)
-  template <class C, class T>
-  static buffer key_from(const ::std::basic_string_view<C, T> &src,
-                         bool make_reference = false) {
-    return buffer(src, make_reference);
-  }
-#endif /* __cpp_lib_string_view >= 201606L */
-
-  static buffer key_from(const char *src, bool make_reference = false) {
-    return buffer(src, make_reference);
-  }
-
-  template <class C, class T, class A>
-  static buffer key_from(const ::std::basic_string<C, T, A> &src,
-                         bool make_reference = false) {
-    return buffer(src, make_reference);
-  }
-
-  static buffer key_from(const silo &&src) noexcept {
-    return buffer(::std::move(src));
-  }
-
-  static buffer key_from(const double ieee754_64bit) {
-    return wrap(::mdbx_key_from_double(ieee754_64bit));
-  }
-
-  static buffer key_from(const double *ieee754_64bit) {
-    return wrap(::mdbx_key_from_ptrdouble(ieee754_64bit));
-  }
-
-  static buffer key_from(const uint64_t unsigned_int64) {
-    return wrap(unsigned_int64);
-  }
-
-  static buffer key_from(const int64_t signed_int64) {
-    return wrap(::mdbx_key_from_int64(signed_int64));
-  }
-
-  static buffer key_from_jsonInteger(const int64_t json_integer) {
-    return wrap(::mdbx_key_from_jsonInteger(json_integer));
-  }
-
-  static buffer key_from(const float ieee754_32bit) {
-    return wrap(::mdbx_key_from_float(ieee754_32bit));
-  }
-
-  static buffer key_from(const float *ieee754_32bit) {
-    return wrap(::mdbx_key_from_ptrfloat(ieee754_32bit));
-  }
-
-  static buffer key_from(const uint32_t unsigned_int32) {
-    return wrap(unsigned_int32);
-  }
-
-  static buffer key_from(const int32_t signed_int32) {
-    return wrap(::mdbx_key_from_int32(signed_int32));
-  }
-};
-
-/// \brief Combines data slice with boolean flag to represent result of certain
-/// operations.
-struct value_result {
-  slice value;
-  bool done;
-  value_result(const slice &value, bool done) noexcept
-      : value(value), done(done) {}
-  value_result(const value_result &) noexcept = default;
-  value_result &operator=(const value_result &) noexcept = default;
-  MDBX_CXX14_CONSTEXPR operator bool() const noexcept {
-    assert(!done || bool(value));
-    return done;
-  }
-};
-
-/// \brief Combines pair of slices for key and value to represent result of
-/// certain operations.
-struct pair {
-  slice key, value;
-  pair(const slice &key, const slice &value) noexcept
-      : key(key), value(value) {}
-  pair(const pair &) noexcept = default;
-  pair &operator=(const pair &) noexcept = default;
-  MDBX_CXX14_CONSTEXPR operator bool() const noexcept {
-    assert(bool(key) == bool(value));
-    return key;
-  }
-};
-
-/// \brief Combines pair of slices for key and value with boolean flag to
-/// represent result of certain operations.
-struct pair_result : public pair {
-  bool done;
-  pair_result(const slice &key, const slice &value, bool done) noexcept
-      : pair(key, value), done(done) {}
-  pair_result(const pair_result &) noexcept = default;
-  pair_result &operator=(const pair_result &) noexcept = default;
-  MDBX_CXX14_CONSTEXPR operator bool() const noexcept {
-    assert(!done || (bool(key) && bool(value)));
-    return done;
-  }
-};
-
-//------------------------------------------------------------------------------
-
-/// \brief Loop control constants for readers enumeration functor and other
-/// cases. \see env::enumerate_readers()
-enum loop_control { continue_loop = 0, exit_loop = INT32_MIN };
-
-/// \brief Kinds of the keys and corresponding modes of comparing it.
-enum class key_mode {
-  usual = MDBX_DB_DEFAULTS,  ///< Usual variable length keys with byte-by-byte
-                             ///< lexicographic comparison like `std::memcmp()`.
-  reverse = MDBX_REVERSEKEY, ///< Variable length keys with byte-by-byte
-                             ///< lexicographic comparison in reverse order,
-                             ///< from the end of the keys to the beginning.
-  ordinal = MDBX_INTEGERKEY, ///< Keys are binary integers in native byte order,
-                             ///< either `uint32_t` or `uint64_t`, and will be
-                             ///< sorted as such. The keys must all be of the
-                             ///< same size and must be aligned while passing
-                             ///< as arguments.
-  msgpack = -1 ///< Keys are in [MessagePack](https://msgpack.org/)
-               ///< format with appropriate comparison.
-               ///< \note Not yet implemented and PRs are welcome.
-};
-
-/// \brief Kind of the values and sorted multi-values with corresponding
-/// comparison.
-enum class value_mode {
-  single = MDBX_DB_DEFAULTS, ///< Usual single value for each key. In terms of
-                             ///< keys, they are unique.
-  multi =
-      MDBX_DUPSORT, ///< A more than one data value could be associated with
-                    ///< each key. Internally each key is stored once, and the
-                    ///< corresponding data values are sorted by byte-by-byte
-                    ///< lexicographic comparison like `std::memcmp()`.
-                    ///< In terms of keys, they are not unique, i.e. has
-                    ///< duplicates which are sorted by associated data values.
-#if CONSTEXPR_ENUM_FLAGS_OPERATIONS || defined(DOXYGEN)
-  multi_reverse =
-      MDBX_DUPSORT |
-      MDBX_REVERSEDUP, ///< A more than one data value could be associated with
-                       ///< each key. Internally each key is stored once, and
-                       ///< the corresponding data values are sorted by
-                       ///< byte-by-byte lexicographic comparison in reverse
-                       ///< order, from the end of the keys to the beginning.
-                       ///< In terms of keys, they are not unique, i.e. has
-                       ///< duplicates which are sorted by associated data
-                       ///< values.
-  multi_samelength =
-      MDBX_DUPSORT |
-      MDBX_DUPFIXED, ///< A more than one data value could be associated with
-                     ///< each key, and all data values must be same length.
-                     ///< Internally each key is stored once, and the
-                     ///< corresponding data values are sorted by byte-by-byte
-                     ///< lexicographic comparison like `std::memcmp()`. In
-                     ///< terms of keys, they are not unique, i.e. has
-                     ///< duplicates which are sorted by associated data values.
-  multi_ordinal =
-      MDBX_DUPSORT | MDBX_DUPFIXED |
-      MDBX_INTEGERDUP, ///< A more than one data value could be associated with
-                       ///< each key, and all data values are binary integers in
-                       ///< native byte order, either `uint32_t` or `uint64_t`,
-                       ///< and will be sorted as such. Internally each key is
-                       ///< stored once, and the corresponding data values are
-                       ///< sorted. In terms of keys, they are not unique, i.e.
-                       ///< has duplicates which are sorted by associated data
-                       ///< values.
-  multi_reverse_samelength =
-      MDBX_DUPSORT | MDBX_REVERSEDUP |
-      MDBX_DUPFIXED, ///< A more than one data value could be associated with
-                     ///< each key, and all data values must be same length.
-                     ///< Internally each key is stored once, and the
-                     ///< corresponding data values are sorted by byte-by-byte
-                     ///< lexicographic comparison in reverse order, from the
-                     ///< end of the keys to the beginning. In terms of keys,
-                     ///< they are not unique, i.e. has duplicates which are
-                     ///< sorted by associated data values.
-  msgpack = -1 ///< A more than one data value could be associated with each
-               ///< key. Values are in [MessagePack](https://msgpack.org/)
-               ///< format with appropriate comparison. Internally each key is
-               ///< stored once, and the corresponding data values are sorted.
-               ///< In terms of keys, they are not unique, i.e. has duplicates
-               ///< which are sorted by associated data values.
-               ///< \note Not yet implemented and PRs are welcome.
-#else
-  multi_reverse = uint32_t(MDBX_DUPSORT) | uint32_t(MDBX_REVERSEDUP),
-  multi_samelength = uint32_t(MDBX_DUPSORT) | uint32_t(MDBX_DUPFIXED),
-  multi_ordinal = uint32_t(MDBX_DUPSORT) | uint32_t(MDBX_DUPFIXED) |
-                  uint32_t(MDBX_INTEGERDUP),
-  multi_reverse_samelength = uint32_t(MDBX_DUPSORT) |
-                             uint32_t(MDBX_REVERSEDUP) | uint32_t(MDBX_DUPFIXED)
-#endif
-};
-
-/// \brief A handle for an individual database (key-value spaces) in the
-/// environment.
-/// \see txn::open_map() \see txn::create_map()
-/// \see txn::clear_map() \see txn::drop_map()
-/// \see txn::get_handle_info() \see txn::get_map_stat()
-/// \see env::close_amp()
-/// \see cursor::map()
-struct LIBMDBX_API_TYPE map_handle {
-  MDBX_dbi dbi{0};
-  MDBX_CXX11_CONSTEXPR map_handle() noexcept {}
-  MDBX_CXX11_CONSTEXPR map_handle(MDBX_dbi dbi) noexcept : dbi(dbi) {}
-  map_handle(const map_handle &) noexcept = default;
-  map_handle &operator=(const map_handle &) noexcept = default;
-  operator bool() const noexcept { return dbi != 0; }
-
-  using flags = ::MDBX_db_flags_t;
-  using state = ::MDBX_dbi_state_t;
-  struct LIBMDBX_API_TYPE info {
-    map_handle::flags flags;
-    map_handle::state state;
-    MDBX_CXX11_CONSTEXPR info(map_handle::flags flags,
-                              map_handle::state state) noexcept;
-    info(const info &) noexcept = default;
-    info &operator=(const info &) noexcept = default;
-    MDBX_CXX11_CONSTEXPR ::mdbx::key_mode key_mode() const noexcept;
-    MDBX_CXX11_CONSTEXPR ::mdbx::value_mode value_mode() const noexcept;
-  };
-};
-
-/// \brief Key-value pairs put mode.
-enum put_mode {
-  insert_unique = MDBX_NOOVERWRITE, ///< Insert only unique keys.
-  upsert = MDBX_UPSERT,             ///< Insert or update.
-  update = MDBX_CURRENT,            ///< Update existing, don't insert new.
-};
-
-/// \brief Unmanaged database environment.
-///
-/// Like other unmanaged classes, `env` allows copying and assignment for
-/// instances, but does not destroys the represented underlying object from the
-/// own class destructor.
-///
-/// An environment supports multiple key-value sub-databases (aka key-value
-/// spaces or tables), all residing in the same shared-memory map.
-class LIBMDBX_API_TYPE env {
-  friend class txn;
-
-protected:
-  MDBX_env *handle_{nullptr};
-  MDBX_CXX11_CONSTEXPR env(MDBX_env *ptr) noexcept;
-
-public:
-  MDBX_CXX11_CONSTEXPR env() noexcept = default;
-  env(const env &) noexcept = default;
-  inline env &operator=(env &&other) noexcept;
-  inline env(env &&other) noexcept;
-  inline ~env() noexcept;
-
-  MDBX_CXX14_CONSTEXPR operator bool() const noexcept;
-  MDBX_CXX14_CONSTEXPR operator const MDBX_env *() const;
-  MDBX_CXX14_CONSTEXPR operator MDBX_env *();
-  friend MDBX_CXX11_CONSTEXPR bool operator==(const env &a,
-                                              const env &b) noexcept;
-  friend MDBX_CXX11_CONSTEXPR bool operator!=(const env &a,
-                                              const env &b) noexcept;
-
-  //----------------------------------------------------------------------------
-
-  /// Database geometry for size management.
-  struct LIBMDBX_API_TYPE geometry {
-    enum : int64_t {
-      default_value = -1,         ///< Means "keep current or use default"
-      minimal_value = 0,          ///< Means "minimal acceptable"
-      maximal_value = INTPTR_MAX, ///< Means "maximal acceptable"
-      kB = 1000,                  ///< \f$10^{3}\f$ bytes
-      MB = kB * 1000,             ///< \f$10^{6}\f$ bytes
-      GB = MB * 1000,             ///< \f$10^{9}\f$ bytes
-      TB = GB * 1000,             ///< \f$10^{12}\f$ bytes
-      PB = TB * 1000,             ///< \f$10^{15}\f$ bytes
-      EB = PB * 1000,             ///< \f$10^{18}\f$ bytes
-      KiB = 1024,                 ///< \f$2^{10}\f$ bytes
-      MiB = KiB << 10,            ///< \f$2^{20}\f$ bytes
-      GiB = MiB << 10,            ///< \f$2^{30}\f$ bytes
-      TiB = GiB << 10,            ///< \f$2^{40}\f$ bytes
-      PiB = TiB << 10,            ///< \f$2^{50}\f$ bytes
-      EiB = PiB << 10,            ///< \f$2^{60}\f$ bytes
-    };
-
-    /// \brief Tagged type for output to std::ostream
-    struct size {
-      intptr_t bytes;
-      MDBX_CXX11_CONSTEXPR size(intptr_t bytes) noexcept : bytes(bytes) {}
-      MDBX_CXX11_CONSTEXPR operator intptr_t() const noexcept { return bytes; }
-    };
-
-    /// \brief The lower bound of database size in bytes.
-    intptr_t size_lower{minimal_value};
-
-    /// \brief The size in bytes to setup the database size for now.
-    /// \details It is recommended always pass \ref default_value in this
-    /// argument except some special cases.
-    intptr_t size_now{default_value};
-
-    /// \brief The upper bound of database size in bytes.
-    /// \details It is recommended to avoid change upper bound while database is
-    /// used by other processes or threaded (i.e. just pass \ref default_value
-    /// in this argument except absolutely necessary). Otherwise you must be
-    /// ready for \ref MDBX_UNABLE_EXTEND_MAPSIZE error(s), unexpected pauses
-    /// during remapping and/or system errors like "address busy", and so on. In
-    /// other words, there is no way to handle a growth of the upper bound
-    /// robustly because there may be a lack of appropriate system resources
-    /// (which are extremely volatile in a multi-process multi-threaded
-    /// environment).
-    intptr_t size_upper{maximal_value};
-
-    /// \brief The growth step in bytes, must be greater than zero to allow the
-    /// database to grow.
-    intptr_t growth_step{default_value};
-
-    /// \brief The shrink threshold in bytes, must be greater than zero to allow
-    /// the database to shrink.
-    intptr_t shrink_threshold{default_value};
-
-    /// \brief The database page size for new database creation
-    /// or \ref default_value otherwise.
-    /// \details Must be power of 2 in the range between \ref MDBX_MIN_PAGESIZE
-    /// and \ref MDBX_MAX_PAGESIZE.
-    intptr_t pagesize{default_value};
-
-    inline geometry &make_fixed(intptr_t size) noexcept;
-    inline geometry &make_dynamic(intptr_t lower = minimal_value,
-                                  intptr_t upper = maximal_value) noexcept;
-  };
-
-  /// \brief Operation mode.
-  enum mode {
-    readonly,       ///< \copydoc MDBX_RDONLY
-    write_file_io,  // don't available on OpenBSD
-    write_mapped_io ///< \copydoc MDBX_WRITEMAP
-  };
-
-  /// \brief Durability level.
-  enum durability {
-    robust_synchronous,         ///< \copydoc MDBX_SYNC_DURABLE
-    half_synchronous_weak_last, ///< \copydoc MDBX_NOMETASYNC
-    lazy_weak_tail,             ///< \copydoc MDBX_SAFE_NOSYNC
-    whole_fragile               ///< \copydoc MDBX_UTTERLY_NOSYNC
-  };
-
-  /// \brief Garbage reclaiming options.
-  struct LIBMDBX_API_TYPE reclaiming_options {
-    /// \copydoc MDBX_LIFORECLAIM
-    bool lifo{false};
-    /// \copydoc MDBX_COALESCE
-    bool coalesce{false};
-    MDBX_CXX11_CONSTEXPR reclaiming_options() noexcept {}
-    reclaiming_options(MDBX_env_flags_t) noexcept;
-  };
-
-  /// \brief Operate options.
-  struct LIBMDBX_API_TYPE operate_options {
-    /// \copydoc MDBX_NOTLS
-    bool orphan_read_transactions{false};
-    bool nested_write_transactions{false};
-    /// \copydoc MDBX_EXCLUSIVE
-    bool exclusive{false};
-    /// \copydoc MDBX_NORDAHEAD
-    bool disable_readahead{false};
-    /// \copydoc MDBX_NOMEMINIT
-    bool disable_clear_memory{false};
-    MDBX_CXX11_CONSTEXPR operate_options() noexcept {}
-    operate_options(MDBX_env_flags_t) noexcept;
-  };
-
-  /// \brief Operate parameters.
-  struct LIBMDBX_API_TYPE operate_parameters {
-    /// \brief The maximum number of named databases for the environment.
-    /// Zero means default value.
-    unsigned max_maps{0};
-    /// \brief The maximum number of threads/reader slots for the environment.
-    /// Zero means default value.
-    unsigned max_readers{0};
-    env::mode mode{write_mapped_io};
-    env::durability durability{robust_synchronous};
-    env::reclaiming_options reclaiming;
-    env::operate_options options;
-
-    MDBX_CXX11_CONSTEXPR operate_parameters() noexcept {}
-    MDBX_env_flags_t make_flags(bool accede = true, ///< \copydoc MDBX_ACCEDE
-                                bool use_subdirectory = false) const;
-    static env::mode mode_from_flags(MDBX_env_flags_t) noexcept;
-    static env::durability durability_from_flags(MDBX_env_flags_t) noexcept;
-    inline static env::reclaiming_options
-    reclaiming_from_flags(MDBX_env_flags_t flags) noexcept;
-    inline static env::operate_options
-    options_from_flags(MDBX_env_flags_t flags) noexcept;
-    operate_parameters(const env &);
-  };
-
-  /// \brief Returns current operation parameters.
-  inline env::operate_parameters get_operation_parameters() const;
-  /// \brief Returns current operation mode.
-  inline env::mode get_mode() const;
-  /// \brief Returns current durability mode.
-  inline env::durability get_durability() const;
-  /// \brief Returns current reclaiming options.
-  inline env::reclaiming_options get_reclaiming() const;
-  /// \brief Returns current operate options.
-  inline env::operate_options get_options() const;
-
-  /// \brief Returns `true` for a freshly created database,
-  /// but `false` if at least one transaction was committed.
-  bool is_pristine() const;
-
-  /// \brief Checks whether the database is empty.
-  bool is_empty() const;
-
-  /// \brief Returns default page size for current system/platform.
-  static size_t default_pagesize() noexcept {
-    return ::mdbx_default_pagesize();
-  }
-
-  struct limits {
-    limits() = delete;
-    /// \brief Returns the minimal database page size in bytes.
-    static inline size_t pagesize_min() noexcept;
-    /// \brief Returns the maximal database page size in bytes.
-    static inline size_t pagesize_max() noexcept;
-    /// \brief Returns the minimal database size in bytes for specified page
-    /// size.
-    static inline size_t dbsize_min(intptr_t pagesize);
-    /// \brief Returns the maximal database size in bytes for specified page
-    /// size.
-    static inline size_t dbsize_max(intptr_t pagesize);
-    /// \brief Returns the minimal key size in bytes for specified database
-    /// flags.
-    static inline size_t key_min(MDBX_db_flags_t flags) noexcept;
-    /// \brief Returns the minimal key size in bytes for specified keys mode.
-    static inline size_t key_min(key_mode mode) noexcept;
-    /// \brief Returns the maximal key size in bytes for specified page size and
-    /// database flags.
-    static inline size_t key_max(intptr_t pagesize, MDBX_db_flags_t flags);
-    /// \brief Returns the maximal key size in bytes for specified page size and
-    /// keys mode.
-    static inline size_t key_max(intptr_t pagesize, key_mode mode);
-    /// \brief Returns the maximal key size in bytes for given environment and
-    /// database flags.
-    static inline size_t key_max(const env &, MDBX_db_flags_t flags);
-    /// \brief Returns the maximal key size in bytes for given environment and
-    /// keys mode.
-    static inline size_t key_max(const env &, key_mode mode);
-    /// \brief Returns the minimal values size in bytes for specified database
-    /// flags.
-    static inline size_t value_min(MDBX_db_flags_t flags) noexcept;
-    /// \brief Returns the minimal values size in bytes for specified values
-    /// mode.
-    static inline size_t value_min(value_mode) noexcept;
-    /// \brief Returns the maximal value size in bytes for specified page size
-    /// and database flags.
-    static inline size_t value_max(intptr_t pagesize, MDBX_db_flags_t flags);
-    /// \brief Returns the maximal value size in bytes for specified page size
-    /// and values mode.
-    static inline size_t value_max(intptr_t pagesize, value_mode);
-    /// \brief Returns the maximal value size in bytes for given environment and
-    /// database flags.
-    static inline size_t value_max(const env &, MDBX_db_flags_t flags);
-    /// \brief Returns the maximal value size in bytes for specified page size
-    /// and values mode.
-    static inline size_t value_max(const env &, value_mode);
-    /// \brief Returns the maximal write transaction size (i.e. limit for
-    /// summary volume of dirty pages) in bytes for specified page size.
-    static inline size_t transaction_size_max(intptr_t pagesize);
-  };
-
-  /// \brief Returns the minimal database size in bytes for the environment.
-  size_t dbsize_min() const { return limits::dbsize_min(this->get_pagesize()); }
-  /// \brief Returns the maximal database size in bytes for the environment.
-  size_t dbsize_max() const { return limits::dbsize_max(this->get_pagesize()); }
-  /// \brief Returns the minimal key size in bytes for specified keys mode.
-  size_t key_min(key_mode mode) const noexcept { return limits::key_min(mode); }
-  /// \brief Returns the maximal key size in bytes for specified keys mode.
-  size_t key_max(key_mode mode) const { return limits::key_max(*this, mode); }
-  /// \brief Returns the minimal value size in bytes for specified values mode.
-  size_t value_min(value_mode mode) const noexcept {
-    return limits::value_min(mode);
-  }
-  /// \brief Returns the maximal value size in bytes for specified values mode.
-  size_t value_max(value_mode mode) const {
-    return limits::value_max(*this, mode);
-  }
-  /// \brief Returns the maximal write transaction size (i.e. limit for summary
-  /// volume of dirty pages) in bytes.
-  size_t transaction_size_max() const {
-    return limits::transaction_size_max(this->get_pagesize());
-  }
-
-  /// \brief Make a copy (backup) of an existing environment to the specified
-  /// path.
-#ifdef MDBX_STD_FILESYSTEM_PATH
-  env &copy(const ::std::filesystem::path &destination, bool compactify,
-            bool force_dynamic_size = false);
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-#if defined(_WIN32) || defined(_WIN64)
-  env &copy(const ::std::wstring &destination, bool compactify,
-            bool force_dynamic_size = false);
-#endif /* Windows */
-  env &copy(const ::std::string &destination, bool compactify,
-            bool force_dynamic_size = false);
-
-  /// \brief Copy an environment to the specified file descriptor.
-  env &copy(filehandle fd, bool compactify, bool force_dynamic_size = false);
-
-  /// \brief Deletion modes for \ref remove().
-  enum remove_mode {
-    /// \brief Just delete the environment's files and directory if any.
-    /// \note On POSIX systems, processes already working with the database will
-    /// continue to work without interference until it close the environment.
-    /// \note On Windows, the behavior of `just_remove` is different
-    /// because the system does not support deleting files that are currently
-    /// memory mapped.
-    just_remove = MDBX_ENV_JUST_DELETE,
-    /// \brief Make sure that the environment is not being used by other
-    /// processes, or return an error otherwise.
-    ensure_unused = MDBX_ENV_ENSURE_UNUSED,
-    /// \brief Wait until other processes closes the environment before
-    /// deletion.
-    wait_for_unused = MDBX_ENV_WAIT_FOR_UNUSED
-  };
-
-  /// \brief Removes the environment's files in a proper and multiprocess-safe
-  /// way.
-#ifdef MDBX_STD_FILESYSTEM_PATH
-  static bool remove(const ::std::filesystem::path &,
-                     const remove_mode mode = just_remove);
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-#if defined(_WIN32) || defined(_WIN64)
-  static bool remove(const ::std::wstring &,
-                     const remove_mode mode = just_remove);
-#endif /* Windows */
-  static bool remove(const ::std::string &,
-                     const remove_mode mode = just_remove);
-
-  /// \brief Statistics for a database in the MDBX environment.
-  using stat = ::MDBX_stat;
-
-  /// \brief Information about the environment.
-  using info = ::MDBX_envinfo;
-
-  /// \brief Returns snapshot statistics about the MDBX environment.
-  inline stat get_stat() const;
-
-  /// \brief Returns pagesize of this MDBX environment.
-  size_t get_pagesize() const { return get_stat().ms_psize; }
-
-  /// \brief Return snapshot information about the MDBX environment.
-  inline info get_info() const;
-
-  /// \brief Return statistics about the MDBX environment accordingly to the
-  /// specified transaction.
-  inline stat get_stat(const txn &) const;
-
-  /// \brief Return information about the MDBX environment accordingly to the
-  /// specified transaction.
-  inline info get_info(const txn &) const;
-
-  /// \brief Returns the file descriptor for the DXB file of MDBX environment.
-  inline filehandle get_filehandle() const;
-
-  /// \brief Return the path that was used for opening the environment.
-  path get_path() const;
-
-  /// Returns environment flags.
-  inline MDBX_env_flags_t get_flags() const;
-
-  /// \brief Returns the maximum number of threads/reader slots for the
-  /// environment.
-  inline unsigned max_readers() const;
-
-  /// \brief Returns the maximum number of named databases for the environment.
-  inline unsigned max_maps() const;
-
-  /// \brief Returns the application context associated with the environment.
-  inline void *get_context() const noexcept;
-
-  /// \brief Sets the application context associated with the environment.
-  inline env &set_context(void *);
-
-  /// \brief Sets threshold to force flush the data buffers to disk, for
-  /// non-sync durability modes.
-  ///
-  /// The threshold value affects all processes which operates with given
-  /// environment until the last process close environment or a new value will
-  /// be settled.
-  /// Data is always written to disk when \ref txn_managed::commit() is called,
-  /// but the operating system may keep it buffered. MDBX always flushes the OS
-  /// buffers upon commit as well, unless the environment was opened with \ref
-  /// whole_fragile, \ref lazy_weak_tail or in part \ref
-  /// half_synchronous_weak_last. The default is 0, than mean no any threshold
-  /// checked, and no additional flush will be made.
-  ///
-  inline env &set_sync_threshold(size_t bytes);
-
-  /// \brief Sets relative period since the last unsteady commit to force flush
-  /// the data buffers to disk, for non-sync durability modes.
-  ///
-  /// The relative period value affects all processes which operates with given
-  /// environment until the last process close environment or a new value will
-  /// be settled.
-  /// Data is always written to disk when \ref txn_managed::commit() is called,
-  /// but the operating system may keep it buffered. MDBX always flushes the OS
-  /// buffers upon commit as well, unless the environment was opened with \ref
-  /// whole_fragile, \ref lazy_weak_tail or in part \ref
-  /// half_synchronous_weak_last. Settled period don't checked asynchronously,
-  /// but only by the \ref txn_managed::commit() and \ref env::sync_to_disk()
-  /// functions. Therefore, in cases where transactions are committed
-  /// infrequently and/or irregularly, polling by \ref env::poll_sync_to_disk()
-  /// may be a reasonable solution to timeout enforcement. The default is 0,
-  /// than mean no any timeout checked, and no additional flush will be made.
-  ///
-  /// \param [in] seconds_16dot16  The period in 1/65536 of second when a
-  /// synchronous flush would be made since the last unsteady commit.
-  inline env &set_sync_period(unsigned seconds_16dot16);
-
-  /// \brief Sets relative period since the last unsteady commit to force flush
-  /// the data buffers to disk, for non-sync durability modes.
-  ///
-  /// The relative period value affects all processes which operates with given
-  /// environment until the last process close environment or a new value will
-  /// be settled.
-  /// Data is always written to disk when \ref txn_managed::commit() is called,
-  /// but the operating system may keep it buffered. MDBX always flushes the OS
-  /// buffers upon commit as well, unless the environment was opened with \ref
-  /// whole_fragile, \ref lazy_weak_tail or in part \ref
-  /// half_synchronous_weak_last. Settled period don't checked asynchronously,
-  /// but only by the \ref txn_managed::commit() and \ref env::sync_to_disk()
-  /// functions. Therefore, in cases where transactions are committed
-  /// infrequently and/or irregularly, polling by \ref env::poll_sync_to_disk()
-  /// may be a reasonable solution to timeout enforcement. The default is 0,
-  /// than mean no any timeout checked, and no additional flush will be made.
-  ///
-  /// \param [in] seconds  The period in second when a synchronous flush would
-  /// be made since the last unsteady commit.
-  inline env &set_sync_period(double seconds);
-
-  /// \brief Alter environment flags.
-  inline env &alter_flags(MDBX_env_flags_t flags, bool on_off);
-
-  /// \brief Set all size-related parameters of environment.
-  inline env &set_geometry(const geometry &size);
-
-  /// \brief Flush the environment data buffers.
-  /// \return `True` if sync done or no data to sync, or `false` if the
-  /// environment is busy by other thread or none of the thresholds are reached.
-  inline bool sync_to_disk(bool force = true, bool nonblock = false);
-
-  /// \brief Performs non-blocking polling of sync-to-disk thresholds.
-  /// \return `True` if sync done or no data to sync, or `false` if the
-  /// environment is busy by other thread or none of the thresholds are reached.
-  bool poll_sync_to_disk() { return sync_to_disk(false, true); }
-
-  /// \brief Close a key-value map (aka sub-database) handle. Normally
-  /// unnecessary.
-  ///
-  /// Closing a database handle is not necessary, but lets \ref txn::open_map()
-  /// reuse the handle value. Usually it's better to set a bigger
-  /// \ref env::operate_parameters::max_maps, unless that value would be
-  /// large.
-  ///
-  /// \note Use with care.
-  /// This call is synchronized via mutex with other calls \ref close_map(), but
-  /// NOT with other transactions running by other threads. The "next" version
-  /// of libmdbx (\ref MithrilDB) will solve this issue.
-  ///
-  /// Handles should only be closed if no other threads are going to reference
-  /// the database handle or one of its cursors any further. Do not close a
-  /// handle if an existing transaction has modified its database. Doing so can
-  /// cause misbehavior from database corruption to errors like
-  /// \ref MDBX_BAD_DBI (since the DB name is gone).
-  inline void close_map(const map_handle &);
-
-  /// \brief Reader information
-  struct reader_info {
-    int slot;                 ///< The reader lock table slot number.
-    mdbx_pid_t pid;           ///< The reader process ID.
-    mdbx_tid_t thread;        ///< The reader thread ID.
-    uint64_t transaction_id;  ///< The ID of the transaction being read,
-                              ///< i.e. the MVCC-snapshot number.
-    uint64_t transaction_lag; ///< The lag from a recent MVCC-snapshot,
-                              ///< i.e. the number of committed write
-                              /// transactions since the current read
-                              /// transaction started.
-    size_t bytes_used; ///< The number of last used page in the MVCC-snapshot
-                       ///< which being read, i.e. database file can't shrinked
-                       ///< beyond this.
-    size_t bytes_retained; ///< The total size of the database pages that
-                           ///< were retired by committed write transactions
-                           ///< after the reader's MVCC-snapshot, i.e. the space
-                           ///< which would be freed after the Reader releases
-                           ///< the MVCC-snapshot for reuse by completion read
-                           ///< transaction.
-
-    MDBX_CXX11_CONSTEXPR reader_info(int slot, mdbx_pid_t pid,
-                                     mdbx_tid_t thread, uint64_t txnid,
-                                     uint64_t lag, size_t used,
-                                     size_t retained) noexcept;
-  };
-
-  /// \brief Enumerate readers.
-  ///
-  /// The VISITOR class must have `int operator(const reader_info&, int serial)`
-  /// which should return \ref continue_loop (zero) to continue enumeration,
-  /// or any non-zero value to exit.
-  ///
-  /// \returns The last value returned from visitor' functor.
-  template <typename VISITOR> inline int enumerate_readers(VISITOR &visitor);
-
-  /// \brief Checks for stale readers in the lock table and
-  /// return number of cleared slots.
-  inline unsigned check_readers();
-
-  /// \brief Sets a Handle-Slow-Readers callback to resolve database
-  /// full/overflow issue due to a reader(s) which prevents the old data from
-  /// being recycled.
-  ///
-  /// Such callback will be triggered in a case where there is not enough free
-  /// space in the database due to long read transaction(s) which impedes
-  /// reusing the pages of an old MVCC snapshot(s).
-  ///
-  /// Using this callback you can choose how to resolve the situation:
-  ///  - abort the write transaction with an error;
-  ///  - wait for the read transaction(s) to complete;
-  ///  - notify a thread performing a long-lived read transaction
-  ///    and wait for an effect;
-  ///  - kill the thread or whole process that performs the long-lived read
-  ///    transaction;
-  ///
-  /// \see long-lived-read
-  inline env &set_HandleSlowReaders(MDBX_hsr_func *);
-
-  /// \brief Returns the current Handle-Slow-Readers callback used to resolve
-  /// database full/overflow issue due to a reader(s) which prevents the old
-  /// data from being recycled.
-  /// \see set_HandleSlowReaders()
-  inline MDBX_hsr_func *get_HandleSlowReaders() const noexcept;
-
-  /// \brief Starts read (read-only) transaction.
-  inline txn_managed start_read() const;
-
-  /// \brief Creates but not start read transaction.
-  inline txn_managed prepare_read() const;
-
-  /// \brief Starts write (read-write) transaction.
-  inline txn_managed start_write(bool dont_wait = false);
-
-  /// \brief Tries to start write (read-write) transaction without blocking.
-  inline txn_managed try_start_write();
-};
-
-/// \brief Managed database environment.
-///
-/// As other managed classes, `env_managed` destroys the represented underlying
-/// object from the own class destructor, but disallows copying and assignment
-/// for instances.
-///
-/// An environment supports multiple key-value databases (aka key-value spaces
-/// or tables), all residing in the same shared-memory map.
-class LIBMDBX_API_TYPE env_managed : public env {
-  using inherited = env;
-  /// delegated constructor for RAII
-  MDBX_CXX11_CONSTEXPR env_managed(MDBX_env *ptr) noexcept : inherited(ptr) {}
-  void setup(unsigned max_maps, unsigned max_readers = 0);
-
-public:
-  MDBX_CXX11_CONSTEXPR env_managed() noexcept = default;
-
-  /// \brief Open existing database.
-#ifdef MDBX_STD_FILESYSTEM_PATH
-  env_managed(const ::std::filesystem::path &, const operate_parameters &,
-              bool accede = true);
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-#if defined(_WIN32) || defined(_WIN64)
-  env_managed(const ::std::wstring &, const operate_parameters &,
-              bool accede = true);
-#endif /* Windows */
-  env_managed(const ::std::string &, const operate_parameters &,
-              bool accede = true);
-
-  /// \brief Additional parameters for creating a new database.
-  struct create_parameters {
-    env::geometry geometry;
-    mdbx_mode_t file_mode_bits{0640};
-    bool use_subdirectory{false};
-  };
-
-  /// \brief Create new or open existing database.
-#ifdef MDBX_STD_FILESYSTEM_PATH
-  env_managed(const ::std::filesystem::path &, const create_parameters &,
-              const operate_parameters &, bool accede = true);
-#endif /* MDBX_STD_FILESYSTEM_PATH */
-#if defined(_WIN32) || defined(_WIN64)
-  env_managed(const ::std::wstring &, const create_parameters &,
-              const operate_parameters &, bool accede = true);
-#endif /* Windows */
-  env_managed(const ::std::string &, const create_parameters &,
-              const operate_parameters &, bool accede = true);
-
-  /// \brief Explicitly closes the environment and release the memory map.
-  ///
-  /// Only a single thread may call this function. All transactions, databases,
-  /// and cursors must already be closed before calling this function. Attempts
-  /// to use any such handles after calling this function will cause a
-  /// `SIGSEGV`. The environment handle will be freed and must not be used again
-  /// after this call.
-  ///
-  /// \param [in] dont_sync  A dont'sync flag, if non-zero the last checkpoint
-  /// will be kept "as is" and may be still "weak" in the \ref lazy_weak_tail
-  /// or \ref whole_fragile modes. Such "weak" checkpoint will be ignored
-  /// on opening next time, and transactions since the last non-weak checkpoint
-  /// (meta-page update) will rolledback for consistency guarantee.
-  void close(bool dont_sync = false);
-
-  env_managed(env_managed &&) = default;
-  env_managed &operator=(env_managed &&) = default;
-  env_managed(const env_managed &) = delete;
-  env_managed &operator=(const env_managed &) = delete;
-  virtual ~env_managed() noexcept;
-};
-
-/// \brief Unmanaged database transaction.
-///
-/// Like other unmanaged classes, `txn` allows copying and assignment for
-/// instances, but does not destroys the represented underlying object from the
-/// own class destructor.
-///
-/// All database operations require a transaction handle. Transactions may be
-/// read-only or read-write.
-class LIBMDBX_API_TYPE txn {
-protected:
-  friend class cursor;
-  MDBX_txn *handle_{nullptr};
-  MDBX_CXX11_CONSTEXPR txn(MDBX_txn *ptr) noexcept;
-
-public:
-  MDBX_CXX11_CONSTEXPR txn() noexcept = default;
-  txn(const txn &) noexcept = default;
-  inline txn &operator=(txn &&other) noexcept;
-  inline txn(txn &&other) noexcept;
-  inline ~txn() noexcept;
-
-  MDBX_CXX14_CONSTEXPR operator bool() const noexcept;
-  MDBX_CXX14_CONSTEXPR operator const MDBX_txn *() const;
-  MDBX_CXX14_CONSTEXPR operator MDBX_txn *();
-  friend MDBX_CXX11_CONSTEXPR bool operator==(const txn &a,
-                                              const txn &b) noexcept;
-  friend MDBX_CXX11_CONSTEXPR bool operator!=(const txn &a,
-                                              const txn &b) noexcept;
-
-  /// \brief Returns the transaction's environment.
-  inline ::mdbx::env env() const noexcept;
-  /// \brief Returns transaction's flags.
-  inline MDBX_txn_flags_t flags() const;
-  /// \brief Return the transaction's ID.
-  inline uint64_t id() const;
-
-  /// \brief Checks whether the given data is on a dirty page.
-  inline bool is_dirty(const void *ptr) const;
-
-  /// \brief Checks whether the transaction is read-only.
-  bool is_readonly() const { return (flags() & MDBX_TXN_RDONLY) != 0; }
-
-  /// \brief Checks whether the transaction is read-write.
-  bool is_readwrite() const { return (flags() & MDBX_TXN_RDONLY) == 0; }
-
-  using info = ::MDBX_txn_info;
-  /// \brief Returns information about the MDBX transaction.
-  inline info get_info(bool scan_reader_lock_table = false) const;
-
-  /// \brief Returns maximal write transaction size (i.e. limit for summary
-  /// volume of dirty pages) in bytes.
-  size_t size_max() const { return env().transaction_size_max(); }
-
-  /// \brief Returns current write transaction size (i.e.summary volume of dirty
-  /// pages) in bytes.
-  size_t size_current() const {
-    assert(is_readwrite());
-    return size_t(get_info().txn_space_dirty);
-  }
-
-  //----------------------------------------------------------------------------
-
-  /// \brief Reset a read-only transaction.
-  inline void reset_reading();
-
-  /// \brief Renew a read-only transaction.
-  inline void renew_reading();
-
-  /// \brief Start nested write transaction.
-  txn_managed start_nested();
-
-  /// \brief Opens cursor for specified key-value map handle.
-  inline cursor_managed open_cursor(map_handle map);
-
-  /// \brief Open existing key-value map.
-  inline map_handle open_map(
-      const char *name,
-      const ::mdbx::key_mode key_mode = ::mdbx::key_mode::usual,
-      const ::mdbx::value_mode value_mode = ::mdbx::value_mode::single) const;
-  /// \brief Open existing key-value map.
-  inline map_handle open_map(
-      const ::std::string &name,
-      const ::mdbx::key_mode key_mode = ::mdbx::key_mode::usual,
-      const ::mdbx::value_mode value_mode = ::mdbx::value_mode::single) const;
-
-  /// \brief Create new or open existing key-value map.
-  inline map_handle
-  create_map(const char *name,
-             const ::mdbx::key_mode key_mode = ::mdbx::key_mode::usual,
-             const ::mdbx::value_mode value_mode = ::mdbx::value_mode::single);
-  /// \brief Create new or open existing key-value map.
-  inline map_handle
-  create_map(const ::std::string &name,
-             const ::mdbx::key_mode key_mode = ::mdbx::key_mode::usual,
-             const ::mdbx::value_mode value_mode = ::mdbx::value_mode::single);
-
-  /// \brief Drops key-value map using handle.
-  inline void drop_map(map_handle map);
-  /// \brief Drops key-value map using name.
-  /// \return `True` if the key-value map existed and was deleted, either
-  /// `false` if the key-value map did not exist and there is nothing to delete.
-  bool drop_map(const char *name, bool throw_if_absent = false);
-  /// \brief Drop key-value map.
-  /// \return `True` if the key-value map existed and was deleted, either
-  /// `false` if the key-value map did not exist and there is nothing to delete.
-  inline bool drop_map(const ::std::string &name, bool throw_if_absent = false);
-
-  /// \brief Clear key-value map.
-  inline void clear_map(map_handle map);
-  /// \return `True` if the key-value map existed and was cleared, either
-  /// `false` if the key-value map did not exist and there is nothing to clear.
-  bool clear_map(const char *name, bool throw_if_absent = false);
-  /// \return `True` if the key-value map existed and was cleared, either
-  /// `false` if the key-value map did not exist and there is nothing to clear.
-  inline bool clear_map(const ::std::string &name,
-                        bool throw_if_absent = false);
-
-  using map_stat = ::MDBX_stat;
-  /// \brief Returns statistics for a sub-database.
-  inline map_stat get_map_stat(map_handle map) const;
-  /// \brief Returns depth (bitmask) information of nested dupsort (multi-value)
-  /// B+trees for given database.
-  inline uint32_t get_tree_deepmask(map_handle map) const;
-  /// \brief Returns information about key-value map (aka sub-database) handle.
-  inline map_handle::info get_handle_info(map_handle map) const;
-
-  using canary = ::MDBX_canary;
-  /// \brief Set integers markers (aka "canary") associated with the
-  /// environment.
-  inline txn &put_canary(const canary &);
-  /// \brief Returns fours integers markers (aka "canary") associated with the
-  /// environment.
-  inline canary get_canary() const;
-
-  /// Reads sequence generator associated with a key-value map (aka
-  /// sub-database).
-  inline uint64_t sequence(map_handle map) const;
-  /// \brief Reads and increment sequence generator associated with a key-value
-  /// map (aka sub-database).
-  inline uint64_t sequence(map_handle map, uint64_t increment);
-
-  /// \brief Compare two keys according to a particular key-value map (aka
-  /// sub-database).
-  inline int compare_keys(map_handle map, const slice &a,
-                          const slice &b) const noexcept;
-  /// \brief Compare two values according to a particular key-value map (aka
-  /// sub-database).
-  inline int compare_values(map_handle map, const slice &a,
-                            const slice &b) const noexcept;
-  /// \brief Compare keys of two pairs according to a particular key-value map
-  /// (aka sub-database).
-  inline int compare_keys(map_handle map, const pair &a,
-                          const pair &b) const noexcept;
-  /// \brief Compare values of two pairs according to a particular key-value map
-  /// (aka sub-database).
-  inline int compare_values(map_handle map, const pair &a,
-                            const pair &b) const noexcept;
-
-  /// \brief Get value by key from a key-value map (aka sub-database).
-  inline slice get(map_handle map, const slice &key) const;
-  /// \brief Get first of multi-value and values count by key from a key-value
-  /// multimap (aka sub-database).
-  inline slice get(map_handle map, slice key, size_t &values_count) const;
-  /// \brief Get value by key from a key-value map (aka sub-database).
-  inline slice get(map_handle map, const slice &key,
-                   const slice &value_at_absence) const;
-  /// \brief Get first of multi-value and values count by key from a key-value
-  /// multimap (aka sub-database).
-  inline slice get(map_handle map, slice key, size_t &values_count,
-                   const slice &value_at_absence) const;
-  /// \brief Get value for equal or great key from a database.
-  /// \return Bundle of key-value pair and boolean flag,
-  /// which will be `true` if the exact key was found and `false` otherwise.
-  inline pair_result get_equal_or_great(map_handle map, const slice &key) const;
-  /// \brief Get value for equal or great key from a database.
-  /// \return Bundle of key-value pair and boolean flag,
-  /// which will be `true` if the exact key was found and `false` otherwise.
-  inline pair_result get_equal_or_great(map_handle map, const slice &key,
-                                        const slice &value_at_absence) const;
-
-  inline MDBX_error_t put(map_handle map, const slice &key, slice *value,
-                          MDBX_put_flags_t flags) noexcept;
-  inline void put(map_handle map, const slice &key, slice value,
-                  put_mode mode) noexcept;
-  inline void insert(map_handle map, const slice &key, slice value);
-  inline value_result try_insert(map_handle map, const slice &key, slice value);
-  inline slice insert_reserve(map_handle map, const slice &key,
-                              size_t value_length);
-  inline value_result try_insert_reserve(map_handle map, const slice &key,
-                                         size_t value_length);
-
-  inline void upsert(map_handle map, const slice &key, const slice &value);
-  inline slice upsert_reserve(map_handle map, const slice &key,
-                              size_t value_length);
-
-  inline void update(map_handle map, const slice &key, const slice &value);
-  inline bool try_update(map_handle map, const slice &key, const slice &value);
-  inline slice update_reserve(map_handle map, const slice &key,
-                              size_t value_length);
-  inline value_result try_update_reserve(map_handle map, const slice &key,
-                                         size_t value_length);
-
-  inline bool erase(map_handle map, const slice &key);
-
-  /// \brief Removes the particular multi-value entry of the key.
-  inline bool erase(map_handle map, const slice &key, const slice &value);
-
-  /// \brief Replaces the particular multi-value of the key with a new value.
-  inline void replace(map_handle map, const slice &key, slice old_value,
-                      const slice &new_value);
-
-  /// \brief Removes and return a value of the key.
-  template <class ALLOCATOR>
-  inline buffer<ALLOCATOR> extract(map_handle map, const slice &key,
-                                   const ALLOCATOR &allocator = ALLOCATOR());
-
-  /// \brief Replaces and returns a value of the key with new one.
-  template <class ALLOCATOR>
-  inline buffer<ALLOCATOR> replace(map_handle map, const slice &key,
-                                   const slice &new_value,
-                                   const ALLOCATOR &allocator = ALLOCATOR());
-
-  template <class ALLOCATOR>
-  inline buffer<ALLOCATOR>
-  replace_reserve(map_handle map, const slice &key, slice &new_value,
-                  const ALLOCATOR &allocator = ALLOCATOR());
-
-  /// \brief Adding a key-value pair, provided that ascending order of the keys
-  /// and (optionally) values are preserved.
-  ///
-  /// Instead of splitting the full b+tree pages, the data will be placed on new
-  /// ones. Thus appending is about two times faster than insertion, and the
-  /// pages will be filled in completely mostly but not half as after splitting
-  /// ones. On the other hand, any subsequent insertion or update with an
-  /// increase in the length of the value will be twice as slow, since it will
-  /// require splitting already filled pages.
-  ///
-  /// \param [in] multivalue_order_preserved
-  /// If `multivalue_order_preserved == true` then the same rules applied for
-  /// to pages of nested b+tree of multimap's values.
-  inline void append(map_handle map, const slice &key, const slice &value,
-                     bool multivalue_order_preserved = true);
-
-  size_t put_multiple(map_handle map, const slice &key,
-                      const size_t value_length, const void *values_array,
-                      size_t values_count, put_mode mode,
-                      bool allow_partial = false);
-  template <typename VALUE>
-  void put_multiple(map_handle map, const slice &key,
-                    const std::vector<VALUE> &vector, put_mode mode) {
-    put_multiple(map, key, sizeof(VALUE), vector.data(), vector.size(), mode,
-                 false);
-  }
-
-  inline ptrdiff_t estimate(map_handle map, pair from, pair to) const;
-  inline ptrdiff_t estimate(map_handle map, slice from, slice to) const;
-  inline ptrdiff_t estimate_from_first(map_handle map, slice to) const;
-  inline ptrdiff_t estimate_to_last(map_handle map, slice from) const;
-};
-
-/// \brief Managed database transaction.
-///
-/// As other managed classes, `txn_managed` destroys the represented underlying
-/// object from the own class destructor, but disallows copying and assignment
-/// for instances.
-///
-/// All database operations require a transaction handle. Transactions may be
-/// read-only or read-write.
-class LIBMDBX_API_TYPE txn_managed : public txn {
-  using inherited = txn;
-  friend class env;
-  friend class txn;
-  /// delegated constructor for RAII
-  MDBX_CXX11_CONSTEXPR txn_managed(MDBX_txn *ptr) noexcept : inherited(ptr) {}
-
-public:
-  MDBX_CXX11_CONSTEXPR txn_managed() noexcept = default;
-  txn_managed(txn_managed &&) = default;
-  txn_managed &operator=(txn_managed &&) = default;
-  txn_managed(const txn_managed &) = delete;
-  txn_managed &operator=(const txn_managed &) = delete;
-  ~txn_managed() noexcept;
-
-  //----------------------------------------------------------------------------
-
-  /// \brief Abandon all the operations of the transaction instead of saving
-  /// them.
-  void abort();
-
-  /// \brief Commit all the operations of a transaction into the database.
-  void commit();
-};
-
-/// \brief Unmanaged cursor.
-///
-/// Like other unmanaged classes, `cursor` allows copying and assignment for
-/// instances, but does not destroys the represented underlying object from the
-/// own class destructor.
-///
-/// \copydetails MDBX_cursor
-class LIBMDBX_API_TYPE cursor {
-protected:
-  MDBX_cursor *handle_{nullptr};
-  MDBX_CXX11_CONSTEXPR cursor(MDBX_cursor *ptr) noexcept;
-
-public:
-  MDBX_CXX11_CONSTEXPR cursor() noexcept = default;
-  cursor(const cursor &) noexcept = default;
-  inline cursor &operator=(cursor &&other) noexcept;
-  inline cursor(cursor &&other) noexcept;
-  inline ~cursor() noexcept;
-  MDBX_CXX14_CONSTEXPR operator bool() const noexcept;
-  MDBX_CXX14_CONSTEXPR operator const MDBX_cursor *() const;
-  MDBX_CXX14_CONSTEXPR operator MDBX_cursor *();
-  friend MDBX_CXX11_CONSTEXPR bool operator==(const cursor &a,
-                                              const cursor &b) noexcept;
-  friend MDBX_CXX11_CONSTEXPR bool operator!=(const cursor &a,
-                                              const cursor &b) noexcept;
-
-  enum move_operation {
-    first = MDBX_FIRST,
-    last = MDBX_LAST,
-    next = MDBX_NEXT,
-    previous = MDBX_PREV,
-    get_current = MDBX_GET_CURRENT,
-
-    multi_prevkey_lastvalue = MDBX_PREV_NODUP,
-    multi_currentkey_firstvalue = MDBX_FIRST_DUP,
-    multi_currentkey_prevvalue = MDBX_PREV_DUP,
-    multi_currentkey_nextvalue = MDBX_NEXT_DUP,
-    multi_currentkey_lastvalue = MDBX_LAST_DUP,
-    multi_nextkey_firstvalue = MDBX_NEXT_NODUP,
-
-    multi_find_pair = MDBX_GET_BOTH,
-    multi_exactkey_lowerboundvalue = MDBX_GET_BOTH_RANGE,
-
-    find_key = MDBX_SET,
-    key_exact = MDBX_SET_KEY,
-    key_lowerbound = MDBX_SET_RANGE
-  };
-
-  struct move_result : public pair_result {
-    inline move_result(const cursor &cursor, bool throw_notfound);
-    inline move_result(cursor &cursor, move_operation operation,
-                       bool throw_notfound);
-    inline move_result(cursor &cursor, move_operation operation,
-                       const slice &key, bool throw_notfound);
-    inline move_result(cursor &cursor, move_operation operation,
-                       const slice &key, const slice &value,
-                       bool throw_notfound);
-    move_result(const move_result &) noexcept = default;
-  };
-
-protected:
-  inline bool move(move_operation operation, MDBX_val *key, MDBX_val *value,
-                   bool throw_notfound) const
-      /* fake const, i.e. for some operations */;
-  inline ptrdiff_t estimate(move_operation operation, MDBX_val *key,
-                            MDBX_val *value) const;
-
-public:
-  inline move_result move(move_operation operation, bool throw_notfound);
-  inline move_result to_first(bool throw_notfound = true);
-  inline move_result to_previous(bool throw_notfound = true);
-  inline move_result to_previous_last_multi(bool throw_notfound = true);
-  inline move_result to_current_first_multi(bool throw_notfound = true);
-  inline move_result to_current_prev_multi(bool throw_notfound = true);
-  inline move_result current(bool throw_notfound = true) const;
-  inline move_result to_current_next_multi(bool throw_notfound = true);
-  inline move_result to_current_last_multi(bool throw_notfound = true);
-  inline move_result to_next_first_multi(bool throw_notfound = true);
-  inline move_result to_next(bool throw_notfound = true);
-  inline move_result to_last(bool throw_notfound = true);
-
-  inline move_result move(move_operation operation, const slice &key,
-                          bool throw_notfound);
-  inline move_result find(const slice &key, bool throw_notfound = true);
-  inline move_result lower_bound(const slice &key, bool throw_notfound = true);
-
-  inline move_result move(move_operation operation, const slice &key,
-                          const slice &value, bool throw_notfound);
-  inline move_result find_multivalue(const slice &key, const slice &value,
-                                     bool throw_notfound = true);
-  inline move_result lower_bound_multivalue(const slice &key,
-                                            const slice &value,
-                                            bool throw_notfound = false);
-
-  inline bool seek(const slice &key);
-  inline bool move(move_operation operation, slice &key, slice &value,
-                   bool throw_notfound);
-
-  /// \brief Return count of duplicates for current key.
-  inline size_t count_multivalue() const;
-
-  inline bool eof() const;
-  inline bool on_first() const;
-  inline bool on_last() const;
-  inline ptrdiff_t estimate(slice key, slice value) const;
-  inline ptrdiff_t estimate(slice key) const;
-  inline ptrdiff_t estimate(move_operation operation) const;
-
-  //----------------------------------------------------------------------------
-
-  /// \brief Renew/bind a cursor with a new transaction and previously used
-  /// key-value map handle.
-  inline void renew(::mdbx::txn &txn);
-
-  /// \brief Bind/renew a cursor with a new transaction and specified key-value
-  /// map handle.
-  inline void bind(::mdbx::txn &txn, ::mdbx::map_handle map_handle);
-
-  /// \brief Returns the cursor's transaction.
-  inline ::mdbx::txn txn() const;
-  inline map_handle map() const;
-
-  inline operator ::mdbx::txn() const { return txn(); }
-  inline operator ::mdbx::map_handle() const { return map(); }
-
-  inline MDBX_error_t put(const slice &key, slice *value,
-                          MDBX_put_flags_t flags) noexcept;
-  inline void insert(const slice &key, slice value);
-  inline value_result try_insert(const slice &key, slice value);
-  inline slice insert_reserve(const slice &key, size_t value_length);
-  inline value_result try_insert_reserve(const slice &key, size_t value_length);
-
-  inline void upsert(const slice &key, const slice &value);
-  inline slice upsert_reserve(const slice &key, size_t value_length);
-
-  inline void update(const slice &key, const slice &value);
-  inline bool try_update(const slice &key, const slice &value);
-  inline slice update_reserve(const slice &key, size_t value_length);
-  inline value_result try_update_reserve(const slice &key, size_t value_length);
-
-  inline bool erase(bool whole_multivalue = false);
-};
-
-/// \brief Managed cursor.
-///
-/// As other managed classes, `cursor_managed` destroys the represented
-/// underlying object from the own class destructor, but disallows copying and
-/// assignment for instances.
-///
-/// \copydetails MDBX_cursor
-class LIBMDBX_API_TYPE cursor_managed : public cursor {
-  using inherited = cursor;
-  friend class txn;
-  /// delegated constructor for RAII
-  MDBX_CXX11_CONSTEXPR cursor_managed(MDBX_cursor *ptr) noexcept
-      : inherited(ptr) {}
-
-public:
-  /// \brief Creates a new managed cursor with underlying object.
-  inline cursor_managed();
-
-  /// \brief Explicitly closes the cursor.
-  void close();
-
-  cursor_managed(cursor_managed &&) = default;
-  cursor_managed &operator=(cursor_managed &&) = default;
-  cursor_managed(const cursor_managed &) = delete;
-  cursor_managed &operator=(const cursor_managed &) = delete;
-  ~cursor_managed() noexcept { ::mdbx_cursor_close(handle_); }
-};
-
-//------------------------------------------------------------------------------
-
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &, const slice &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &, const pair &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &, const pair_result &);
-template <class ALLOCATOR>
-inline ::std::ostream &operator<<(::std::ostream &out,
-                                  const buffer<ALLOCATOR> &it) {
-  return (it.is_freestanding()
-              ? out << "buf-" << it.headroom() << "." << it.tailroom()
-              : out << "ref-")
-         << it.slice();
-}
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const env::geometry::size &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &, const env::geometry &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const env::operate_parameters &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &, const env::mode &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const env::durability &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const env::reclaiming_options &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const env::operate_options &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const env_managed::create_parameters &);
-
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const MDBX_log_level_t &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &,
-                                       const MDBX_debug_flags_t &);
-LIBMDBX_API ::std::ostream &operator<<(::std::ostream &, const error &);
-inline ::std::ostream &operator<<(::std::ostream &out,
-                                  const MDBX_error_t &errcode) {
-  return out << error(errcode);
-}
-
-//==============================================================================
-//
-// Inline body of the libmdbx C++ API (preliminary draft)
-//
-
-MDBX_CXX11_CONSTEXPR const version_info &get_version() noexcept {
-  return ::mdbx_version;
-}
-MDBX_CXX11_CONSTEXPR const build_info &get_build() noexcept {
-  return ::mdbx_build;
-}
-
-static MDBX_CXX17_CONSTEXPR size_t strlen(const char *c_str) noexcept {
-#if defined(__cpp_lib_is_constant_evaluated) &&                                \
-    __cpp_lib_is_constant_evaluated >= 201811L
-  if (::std::is_constant_evaluated()) {
-    for (size_t i = 0; c_str; ++i)
-      if (!c_str[i])
-        return i;
-    return 0;
-  }
-#endif /* __cpp_lib_is_constant_evaluated >= 201811 */
-#if defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201606L
-  return c_str ? ::std::string_view(c_str).length() : 0;
-#else
-  return c_str ? ::std::strlen(c_str) : 0;
-#endif
-}
-
-MDBX_CXX14_CONSTEXPR size_t check_length(size_t bytes) {
-  if (MDBX_UNLIKELY(bytes > size_t(MDBX_MAXDATASIZE)))
-    MDBX_CXX20_UNLIKELY throw_max_length_exceeded();
-  return bytes;
-}
-
-inline bool exception_thunk::is_clean() const noexcept { return !captured_; }
-
-inline void exception_thunk::capture() noexcept {
-  assert(is_clean());
-  captured_ = ::std::current_exception();
-}
-
-inline void exception_thunk::rethrow_captured() const {
-  if (captured_)
-    MDBX_CXX20_UNLIKELY ::std::rethrow_exception(captured_);
-}
-
-//------------------------------------------------------------------------------
-
-MDBX_CXX11_CONSTEXPR error::error(MDBX_error_t error_code) noexcept
-    : code_(error_code) {}
-
-inline error &error::operator=(MDBX_error_t error_code) noexcept {
-  code_ = error_code;
-  return *this;
-}
-
-MDBX_CXX11_CONSTEXPR bool operator==(const error &a, const error &b) noexcept {
-  return a.code_ == b.code_;
-}
-
-MDBX_CXX11_CONSTEXPR bool operator!=(const error &a, const error &b) noexcept {
-  return !(a == b);
-}
-
-MDBX_CXX11_CONSTEXPR bool error::is_success() const noexcept {
-  return code_ == MDBX_SUCCESS;
-}
-
-MDBX_CXX11_CONSTEXPR bool error::is_result_true() const noexcept {
-  return code_ == MDBX_RESULT_FALSE;
-}
-
-MDBX_CXX11_CONSTEXPR bool error::is_result_false() const noexcept {
-  return code_ == MDBX_RESULT_TRUE;
-}
-
-MDBX_CXX11_CONSTEXPR bool error::is_failure() const noexcept {
-  return code_ != MDBX_SUCCESS && code_ != MDBX_RESULT_TRUE;
-}
-
-MDBX_CXX11_CONSTEXPR MDBX_error_t error::code() const noexcept { return code_; }
-
-MDBX_CXX11_CONSTEXPR bool error::is_mdbx_error() const noexcept {
-  return (code() >= MDBX_FIRST_LMDB_ERRCODE &&
-          code() <= MDBX_LAST_LMDB_ERRCODE) ||
-         (code() >= MDBX_FIRST_ADDED_ERRCODE &&
-          code() <= MDBX_LAST_ADDED_ERRCODE);
-}
-
-inline void error::throw_exception(int error_code) {
-  const error trouble(static_cast<MDBX_error_t>(error_code));
-  trouble.throw_exception();
-}
-
-inline void error::throw_on_failure() const {
-  if (MDBX_UNLIKELY(is_failure()))
-    MDBX_CXX20_UNLIKELY throw_exception();
-}
-
-inline void error::success_or_throw() const {
-  if (MDBX_UNLIKELY(!is_success()))
-    MDBX_CXX20_UNLIKELY throw_exception();
-}
-
-inline void error::success_or_throw(const exception_thunk &thunk) const {
-  assert(thunk.is_clean() || code() != MDBX_SUCCESS);
-  if (MDBX_UNLIKELY(!is_success())) {
-    MDBX_CXX20_UNLIKELY if (!thunk.is_clean()) thunk.rethrow_captured();
-    else throw_exception();
-  }
-}
-
-inline void error::panic_on_failure(const char *context_where,
-                                    const char *func_who) const noexcept {
-  if (MDBX_UNLIKELY(is_failure()))
-    MDBX_CXX20_UNLIKELY panic(context_where, func_who);
-}
-
-inline void error::success_or_panic(const char *context_where,
-                                    const char *func_who) const noexcept {
-  if (MDBX_UNLIKELY(!is_success()))
-    MDBX_CXX20_UNLIKELY panic(context_where, func_who);
-}
-
-inline void error::throw_on_nullptr(const void *ptr, MDBX_error_t error_code) {
-  if (MDBX_UNLIKELY(ptr == nullptr))
-    MDBX_CXX20_UNLIKELY error(error_code).throw_exception();
-}
-
-inline void error::throw_on_failure(int error_code) {
-  error rc(static_cast<MDBX_error_t>(error_code));
-  rc.throw_on_failure();
-}
-
-inline void error::success_or_throw(MDBX_error_t error_code) {
-  error rc(error_code);
-  rc.success_or_throw();
-}
-
-inline bool error::boolean_or_throw(int error_code) {
-  switch (error_code) {
-  case MDBX_RESULT_FALSE:
-    return false;
-  case MDBX_RESULT_TRUE:
-    return true;
-  default:
-    MDBX_CXX20_UNLIKELY throw_exception(error_code);
-  }
-}
-
-inline void error::success_or_throw(int error_code,
-                                    const exception_thunk &thunk) {
-  error rc(static_cast<MDBX_error_t>(error_code));
-  rc.success_or_throw(thunk);
-}
-
-inline void error::panic_on_failure(int error_code, const char *context_where,
-                                    const char *func_who) noexcept {
-  error rc(static_cast<MDBX_error_t>(error_code));
-  rc.panic_on_failure(context_where, func_who);
-}
-
-inline void error::success_or_panic(int error_code, const char *context_where,
-                                    const char *func_who) noexcept {
-  error rc(static_cast<MDBX_error_t>(error_code));
-  rc.success_or_panic(context_where, func_who);
-}
-
-//------------------------------------------------------------------------------
-
-MDBX_CXX11_CONSTEXPR slice::slice() noexcept : ::MDBX_val({nullptr, 0}) {}
-
-MDBX_CXX14_CONSTEXPR slice::slice(const void *ptr, size_t bytes)
-    : ::MDBX_val({const_cast<void *>(ptr), check_length(bytes)}) {}
-
-MDBX_CXX14_CONSTEXPR slice::slice(const void *begin, const void *end)
-    : slice(begin, static_cast<const byte *>(end) -
-                       static_cast<const byte *>(begin)) {}
-
-MDBX_CXX17_CONSTEXPR slice::slice(const char *c_str)
-    : slice(c_str, ::mdbx::strlen(c_str)) {}
-
-MDBX_CXX14_CONSTEXPR slice::slice(const MDBX_val &src)
-    : slice(src.iov_base, src.iov_len) {}
-
-inline slice::slice(MDBX_val &&src) : slice(src) { src.iov_base = nullptr; }
-
-inline slice::slice(slice &&src) noexcept : slice(src) { src.invalidate(); }
-
-inline slice &slice::assign(const void *ptr, size_t bytes) {
-  iov_base = const_cast<void *>(ptr);
-  iov_len = check_length(bytes);
-  return *this;
-}
-
-inline slice &slice::assign(const slice &src) noexcept {
-  iov_base = src.iov_base;
-  iov_len = src.iov_len;
-  return *this;
-}
-
-inline slice &slice::assign(const ::MDBX_val &src) {
-  return assign(src.iov_base, src.iov_len);
-}
-
-slice &slice::assign(slice &&src) noexcept {
-  assign(src);
-  src.invalidate();
-  return *this;
-}
-
-inline slice &slice::assign(::MDBX_val &&src) {
-  assign(src.iov_base, src.iov_len);
-  src.iov_base = nullptr;
-  return *this;
-}
-
-inline slice &slice::assign(const void *begin, const void *end) {
-  return assign(begin, static_cast<const byte *>(end) -
-                           static_cast<const byte *>(begin));
-}
-
-inline slice &slice::assign(const char *c_str) {
-  return assign(c_str, ::mdbx::strlen(c_str));
-}
-
-inline slice &slice::operator=(slice &&src) noexcept {
-  return assign(::std::move(src));
-}
-
-inline slice &slice::operator=(::MDBX_val &&src) {
-  return assign(::std::move(src));
-}
-
-inline void slice::swap(slice &other) noexcept {
-  const auto temp = *this;
-  *this = other;
-  other = temp;
-}
-
-MDBX_CXX11_CONSTEXPR const mdbx::byte *slice::byte_ptr() const noexcept {
-  return static_cast<const byte *>(iov_base);
-}
-
-MDBX_CXX11_CONSTEXPR const char *slice::char_ptr() const noexcept {
-  return static_cast<const char *>(iov_base);
-}
-
-MDBX_CXX11_CONSTEXPR const void *slice::data() const noexcept {
-  return iov_base;
-}
-
-MDBX_CXX11_CONSTEXPR size_t slice::length() const noexcept { return iov_len; }
-
-MDBX_CXX11_CONSTEXPR bool slice::empty() const noexcept {
-  return length() == 0;
-}
-
-MDBX_CXX11_CONSTEXPR bool slice::is_null() const noexcept {
-  return data() == nullptr;
-}
-
-MDBX_CXX11_CONSTEXPR size_t slice::size() const noexcept { return length(); }
-
-MDBX_CXX11_CONSTEXPR slice::operator bool() const noexcept {
-  return !is_null();
-}
-
-inline void slice::invalidate() noexcept { iov_base = nullptr; }
-
-inline void slice::clear() noexcept {
-  iov_base = nullptr;
-  iov_len = 0;
-}
-
-inline void slice::remove_prefix(size_t n) noexcept {
-  assert(n <= size());
-  iov_base = static_cast<byte *>(iov_base) + n;
-  iov_len -= n;
-}
-
-inline void slice::safe_remove_prefix(size_t n) {
-  if (MDBX_UNLIKELY(n > size()))
-    MDBX_CXX20_UNLIKELY throw_out_range();
-  remove_prefix(n);
-}
-
-inline void slice::remove_suffix(size_t n) noexcept {
-  assert(n <= size());
-  iov_len -= n;
-}
-
-inline void slice::safe_remove_suffix(size_t n) {
-  if (MDBX_UNLIKELY(n > size()))
-    MDBX_CXX20_UNLIKELY throw_out_range();
-  remove_suffix(n);
-}
-
-inline bool slice::starts_with(const slice &prefix) const noexcept {
-  return length() >= prefix.length() &&
-         ::std::memcmp(data(), prefix.data(), prefix.length()) == 0;
-}
-
-inline bool slice::ends_with(const slice &suffix) const noexcept {
-  return length() >= suffix.length() &&
-         ::std::memcmp(byte_ptr() + length() - suffix.length(), suffix.data(),
-                       suffix.length()) == 0;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION MDBX_CXX14_CONSTEXPR size_t
-slice::hash_value() const noexcept {
-  size_t h = length() * 3977471;
-  for (size_t i = 0; i < length(); ++i)
-    h = (h ^ static_cast<const uint8_t *>(data())[i]) * 1664525 + 1013904223;
-  return h ^ 3863194411 * (h >> 11);
-}
-
-inline byte slice::operator[](size_t n) const noexcept {
-  assert(n < size());
-  return byte_ptr()[n];
-}
-
-inline byte slice::at(size_t n) const {
-  if (MDBX_UNLIKELY(n >= size()))
-    MDBX_CXX20_UNLIKELY throw_out_range();
-  return byte_ptr()[n];
-}
-
-inline slice slice::head(size_t n) const noexcept {
-  assert(n <= size());
-  return slice(data(), n);
-}
-
-inline slice slice::tail(size_t n) const noexcept {
-  assert(n <= size());
-  return slice(char_ptr() + size() - n, n);
-}
-
-inline slice slice::middle(size_t from, size_t n) const noexcept {
-  assert(from + n <= size());
-  return slice(char_ptr() + from, n);
-}
-
-inline slice slice::safe_head(size_t n) const {
-  if (MDBX_UNLIKELY(n > size()))
-    MDBX_CXX20_UNLIKELY throw_out_range();
-  return head(n);
-}
-
-inline slice slice::safe_tail(size_t n) const {
-  if (MDBX_UNLIKELY(n > size()))
-    MDBX_CXX20_UNLIKELY throw_out_range();
-  return tail(n);
-}
-
-inline slice slice::safe_middle(size_t from, size_t n) const {
-  if (MDBX_UNLIKELY(n > max_length))
-    MDBX_CXX20_UNLIKELY throw_max_length_exceeded();
-  if (MDBX_UNLIKELY(from + n > size()))
-    MDBX_CXX20_UNLIKELY throw_out_range();
-  return middle(from, n);
-}
-
-inline intptr_t slice::compare_fast(const slice &a, const slice &b) noexcept {
-  const intptr_t diff = a.length() - b.length();
-  return diff ? diff
-              : (a.data() == b.data())
-                    ? 0
-                    : ::std::memcmp(a.data(), b.data(), a.length());
-}
-
-inline intptr_t slice::compare_lexicographically(const slice &a,
-                                                 const slice &b) noexcept {
-  const intptr_t diff =
-      ::std::memcmp(a.data(), b.data(), ::std::min(a.length(), b.length()));
-  return diff ? diff : intptr_t(a.length() - b.length());
-}
-
-MDBX_NOTHROW_PURE_FUNCTION inline bool operator==(const slice &a,
-                                                  const slice &b) noexcept {
-  return slice::compare_fast(a, b) == 0;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION inline bool operator<(const slice &a,
-                                                 const slice &b) noexcept {
-  return slice::compare_lexicographically(a, b) < 0;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION inline bool operator>(const slice &a,
-                                                 const slice &b) noexcept {
-  return slice::compare_lexicographically(a, b) > 0;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION inline bool operator<=(const slice &a,
-                                                  const slice &b) noexcept {
-  return slice::compare_lexicographically(a, b) <= 0;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION inline bool operator>=(const slice &a,
-                                                  const slice &b) noexcept {
-  return slice::compare_lexicographically(a, b) >= 0;
-}
-
-MDBX_NOTHROW_PURE_FUNCTION inline bool operator!=(const slice &a,
-                                                  const slice &b) noexcept {
-  return slice::compare_fast(a, b) != 0;
-}
-
-template <class ALLOCATOR>
-inline ::mdbx::string<ALLOCATOR>
-slice::hex_encode(bool uppercase, const ALLOCATOR &allocator) const {
-  ::mdbx::string<ALLOCATOR> result(allocator);
-  if (MDBX_LIKELY(length() > 0)) {
-    result.resize(to_hex_bytes());
-    result.resize(to_hex(const_cast<char *>(result.data()), result.capacity()) -
-                      result.data(),
-                  uppercase);
-  }
-  return result;
-}
-
-template <class ALLOCATOR>
-inline ::mdbx::string<ALLOCATOR>
-slice::hex_decode(const ALLOCATOR &allocator) const {
-  ::mdbx::string<ALLOCATOR> result(allocator);
-  if (MDBX_LIKELY(length() > 0)) {
-    result.resize(from_hex_bytes());
-    result.resize(
-        from_hex(static_cast<byte *>(
-                     static_cast<void *>(const_cast<char *>(result.data()))),
-                 result.capacity()) -
-        static_cast<const byte *>(static_cast<const void *>(result.data())));
-  }
-  return result;
-}
-
-template <class ALLOCATOR>
-inline ::mdbx::string<ALLOCATOR>
-slice::base58_encode(const ALLOCATOR &allocator) const {
-  ::mdbx::string<ALLOCATOR> result(allocator);
-  if (MDBX_LIKELY(length() > 0)) {
-    result.resize(to_base58_bytes());
-    result.resize(
-        to_base58(const_cast<char *>(result.data()), result.capacity()) -
-        result.data());
-  }
-  return result;
-}
-
-template <class ALLOCATOR>
-inline ::mdbx::string<ALLOCATOR>
-slice::base58_decode(const ALLOCATOR &allocator) const {
-  ::mdbx::string<ALLOCATOR> result(allocator);
-  if (MDBX_LIKELY(length() > 0)) {
-    result.resize(from_base58_bytes());
-    result.resize(
-        from_base58(static_cast<byte *>(
-                        static_cast<void *>(const_cast<char *>(result.data()))),
-                    result.capacity()) -
-        static_cast<const byte *>(static_cast<const void *>(result.data())));
-  }
-  return result;
-}
-
-template <class ALLOCATOR>
-inline ::mdbx::string<ALLOCATOR>
-slice::base64_encode(const ALLOCATOR &allocator) const {
-  ::mdbx::string<ALLOCATOR> result(allocator);
-  if (MDBX_LIKELY(length() > 0)) {
-    result.resize(to_base64_bytes());
-    result.resize(
-        to_base64(const_cast<char *>(result.data()), result.capacity()) -
-        result.data());
-  }
-  return result;
-}
-
-template <class ALLOCATOR>
-inline ::mdbx::string<ALLOCATOR>
-slice::base64_decode(const ALLOCATOR &allocator) const {
-  ::mdbx::string<ALLOCATOR> result(allocator);
-  if (MDBX_LIKELY(length() > 0)) {
-    result.resize(from_base64_bytes());
-    result.resize(
-        from_base64(static_cast<byte *>(
-                        static_cast<void *>(const_cast<char *>(result.data()))),
-                    result.capacity()) -
-        static_cast<const byte *>(static_cast<const void *>(result.data())));
-  }
-  return result;
-}
-
-//------------------------------------------------------------------------------
-
-MDBX_CXX11_CONSTEXPR map_handle::info::info(map_handle::flags flags,
-                                            map_handle::state state) noexcept
-    : flags(flags), state(state) {}
-
-MDBX_CXX11_CONSTEXPR ::mdbx::key_mode
-map_handle::info::key_mode() const noexcept {
-  return ::mdbx::key_mode(flags & (MDBX_REVERSEKEY | MDBX_INTEGERKEY));
-}
-
-MDBX_CXX11_CONSTEXPR ::mdbx::value_mode
-map_handle::info::value_mode() const noexcept {
-  return ::mdbx::value_mode(flags & (MDBX_DUPSORT | MDBX_REVERSEDUP |
-                                     MDBX_DUPFIXED | MDBX_INTEGERDUP));
-}
-
-//------------------------------------------------------------------------------
-
-MDBX_CXX11_CONSTEXPR env::env(MDBX_env *ptr) noexcept : handle_(ptr) {}
-
-inline env &env::operator=(env &&other) noexcept {
-  handle_ = other.handle_;
-  other.handle_ = nullptr;
-  return *this;
-}
-
-inline env::env(env &&other) noexcept : handle_(other.handle_) {
-  other.handle_ = nullptr;
-}
-
-inline env::~env() noexcept {
-#ifndef NDEBUG
-  handle_ = reinterpret_cast<MDBX_env *>(uintptr_t(0xDeadBeef));
-#endif
-}
-
-MDBX_CXX14_CONSTEXPR env::operator bool() const noexcept {
-  return handle_ != nullptr;
-}
-
-MDBX_CXX14_CONSTEXPR env::operator const MDBX_env *() const { return handle_; }
-
-MDBX_CXX14_CONSTEXPR env::operator MDBX_env *() { return handle_; }
-
-MDBX_CXX11_CONSTEXPR bool operator==(const env &a, const env &b) noexcept {
-  return a.handle_ == b.handle_;
-}
-
-MDBX_CXX11_CONSTEXPR bool operator!=(const env &a, const env &b) noexcept {
-  return a.handle_ != b.handle_;
-}
-
-inline env::geometry &env::geometry::make_fixed(intptr_t size) noexcept {
-  size_lower = size_now = size_upper = size;
-  growth_step = shrink_threshold = 0;
-  return *this;
-}
-
-inline env::geometry &env::geometry::make_dynamic(intptr_t lower,
-                                                  intptr_t upper) noexcept {
-  size_now = size_lower = lower;
-  size_upper = upper;
-  growth_step = shrink_threshold = default_value;
-  return *this;
-}
-
-inline env::reclaiming_options env::operate_parameters::reclaiming_from_flags(
-    MDBX_env_flags_t flags) noexcept {
-  return reclaiming_options(flags);
-}
-
-inline env::operate_options
-env::operate_parameters::options_from_flags(MDBX_env_flags_t flags) noexcept {
-  return operate_options(flags);
-}
-
-inline size_t env::limits::pagesize_min() noexcept { return MDBX_MIN_PAGESIZE; }
-
-inline size_t env::limits::pagesize_max() noexcept { return MDBX_MAX_PAGESIZE; }
-
-inline size_t env::limits::dbsize_min(intptr_t pagesize) {
-  const intptr_t result = mdbx_limits_dbsize_min(pagesize);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline size_t env::limits::dbsize_max(intptr_t pagesize) {
-  const intptr_t result = mdbx_limits_dbsize_max(pagesize);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline size_t env::limits::key_min(MDBX_db_flags_t flags) noexcept {
-  return (flags & MDBX_INTEGERKEY) ? 4 : 0;
-}
-
-inline size_t env::limits::key_min(key_mode mode) noexcept {
-  return key_min(MDBX_db_flags_t(mode));
-}
-
-inline size_t env::limits::key_max(intptr_t pagesize, MDBX_db_flags_t flags) {
-  const intptr_t result = mdbx_limits_keysize_max(pagesize, flags);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline size_t env::limits::key_max(intptr_t pagesize, key_mode mode) {
-  return key_max(pagesize, MDBX_db_flags_t(mode));
-}
-
-inline size_t env::limits::key_max(const env &env, MDBX_db_flags_t flags) {
-  const intptr_t result = mdbx_env_get_maxkeysize_ex(env, flags);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline size_t env::limits::key_max(const env &env, key_mode mode) {
-  return key_max(env, MDBX_db_flags_t(mode));
-}
-
-inline size_t env::limits::value_min(MDBX_db_flags_t flags) noexcept {
-  return (flags & MDBX_INTEGERDUP) ? 4 : 0;
-}
-
-inline size_t env::limits::value_min(value_mode mode) noexcept {
-  return value_min(MDBX_db_flags_t(mode));
-}
-
-inline size_t env::limits::value_max(intptr_t pagesize, MDBX_db_flags_t flags) {
-  const intptr_t result = mdbx_limits_valsize_max(pagesize, flags);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline size_t env::limits::value_max(intptr_t pagesize, value_mode mode) {
-  return value_max(pagesize, MDBX_db_flags_t(mode));
-}
-
-inline size_t env::limits::value_max(const env &env, MDBX_db_flags_t flags) {
-  const intptr_t result = mdbx_env_get_maxvalsize_ex(env, flags);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline size_t env::limits::value_max(const env &env, value_mode mode) {
-  return value_max(env, MDBX_db_flags_t(mode));
-}
-
-inline size_t env::limits::transaction_size_max(intptr_t pagesize) {
-  const intptr_t result = mdbx_limits_txnsize_max(pagesize);
-  if (result < 0)
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_EINVAL);
-  return static_cast<size_t>(result);
-}
-
-inline env::operate_parameters env::get_operation_parameters() const {
-  return env::operate_parameters(*this);
-}
-
-inline env::mode env::get_mode() const {
-  return operate_parameters::mode_from_flags(get_flags());
-}
-
-inline env::durability env::get_durability() const {
-  return env::operate_parameters::durability_from_flags(get_flags());
-}
-
-inline env::reclaiming_options env::get_reclaiming() const {
-  return env::operate_parameters::reclaiming_from_flags(get_flags());
-}
-
-inline env::operate_options env::get_options() const {
-  return env::operate_parameters::options_from_flags(get_flags());
-}
-
-inline env::stat env::get_stat() const {
-  env::stat r;
-  error::success_or_throw(::mdbx_env_stat_ex(handle_, nullptr, &r, sizeof(r)));
-  return r;
-}
-
-inline env::stat env::get_stat(const txn &txn) const {
-  env::stat r;
-  error::success_or_throw(::mdbx_env_stat_ex(handle_, txn, &r, sizeof(r)));
-  return r;
-}
-
-inline env::info env::get_info() const {
-  env::info r;
-  error::success_or_throw(::mdbx_env_info_ex(handle_, nullptr, &r, sizeof(r)));
-  return r;
-}
-
-inline env::info env::get_info(const txn &txn) const {
-  env::info r;
-  error::success_or_throw(::mdbx_env_info_ex(handle_, txn, &r, sizeof(r)));
-  return r;
-}
-
-inline filehandle env::get_filehandle() const {
-  filehandle fd;
-  error::success_or_throw(::mdbx_env_get_fd(handle_, &fd));
-  return fd;
-}
-
-inline MDBX_env_flags_t env::get_flags() const {
-  unsigned bits;
-  error::success_or_throw(::mdbx_env_get_flags(handle_, &bits));
-  return MDBX_env_flags_t(bits);
-}
-
-inline unsigned env::max_readers() const {
-  unsigned r;
-  error::success_or_throw(::mdbx_env_get_maxreaders(handle_, &r));
-  return r;
-}
-
-inline unsigned env::max_maps() const {
-  unsigned r;
-  error::success_or_throw(::mdbx_env_get_maxdbs(handle_, &r));
-  return r;
-}
-
-inline void *env::get_context() const noexcept {
-  return mdbx_env_get_userctx(handle_);
-}
-
-inline env &env::set_context(void *ptr) {
-  error::success_or_throw(::mdbx_env_set_userctx(handle_, ptr));
-  return *this;
-}
-
-inline env &env::set_sync_threshold(size_t bytes) {
-  error::success_or_throw(::mdbx_env_set_syncbytes(handle_, bytes));
-  return *this;
-}
-
-inline env &env::set_sync_period(unsigned seconds_16dot16) {
-  error::success_or_throw(::mdbx_env_set_syncperiod(handle_, seconds_16dot16));
-  return *this;
-}
-
-inline env &env::set_sync_period(double seconds) {
-  return set_sync_period(unsigned(seconds * 65536));
-}
-
-inline env &env::alter_flags(MDBX_env_flags_t flags, bool on_off) {
-  error::success_or_throw(::mdbx_env_set_flags(handle_, flags, on_off));
-  return *this;
-}
-
-inline env &env::set_geometry(const geometry &geo) {
-  error::success_or_throw(::mdbx_env_set_geometry(
-      handle_, geo.size_lower, geo.size_now, geo.size_upper, geo.growth_step,
-      geo.shrink_threshold, geo.pagesize));
-  return *this;
-}
-
-inline bool env::sync_to_disk(bool force, bool nonblock) {
-  const int err = ::mdbx_env_sync_ex(handle_, force, nonblock);
-  switch (err) {
-  case MDBX_SUCCESS /* flush done */:
-  case MDBX_RESULT_TRUE /* no data pending for flush to disk */:
-    return true;
-  case MDBX_BUSY /* the environment is used by other thread */:
-    return false;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline void env::close_map(const map_handle &handle) {
-  error::success_or_throw(::mdbx_dbi_close(*this, handle.dbi));
-}
-
-MDBX_CXX11_CONSTEXPR
-env::reader_info::reader_info(int slot, mdbx_pid_t pid, mdbx_tid_t thread,
-                              uint64_t txnid, uint64_t lag, size_t used,
-                              size_t retained) noexcept
-    : slot(slot), pid(pid), thread(thread), transaction_id(txnid),
-      transaction_lag(lag), bytes_used(used), bytes_retained(retained) {}
-
-template <typename VISITOR>
-inline int env::enumerate_readers(VISITOR &visitor) {
-  struct reader_visitor_thunk : public exception_thunk {
-    VISITOR &visitor_;
-    static int cb(void *ctx, int number, int slot, mdbx_pid_t pid,
-                  mdbx_tid_t thread, uint64_t txnid, uint64_t lag, size_t used,
-                  size_t retained) noexcept {
-      reader_visitor_thunk *thunk = static_cast<reader_visitor_thunk *>(ctx);
-      assert(thunk->is_clean());
-      try {
-        const reader_info info(slot, pid, thread, txnid, lag, used, retained);
-        return loop_control(thunk->visitor_(info, number));
-      } catch (... /* capture any exception to rethrow it over C code */) {
-        thunk->capture();
-        return loop_control::exit_loop;
-      }
-    }
-    MDBX_CXX11_CONSTEXPR reader_visitor_thunk(VISITOR &visitor) noexcept
-        : visitor_(visitor) {}
-  };
-  reader_visitor_thunk thunk(visitor);
-  const auto rc = ::mdbx_reader_list(*this, thunk.cb, &thunk);
-  thunk.rethrow_captured();
-  return rc;
-}
-
-inline unsigned env::check_readers() {
-  int dead_count;
-  error::throw_on_failure(::mdbx_reader_check(*this, &dead_count));
-  assert(dead_count >= 0);
-  return static_cast<unsigned>(dead_count);
-}
-
-inline env &env::set_HandleSlowReaders(MDBX_hsr_func *cb) {
-  error::success_or_throw(::mdbx_env_set_hsr(handle_, cb));
-  return *this;
-}
-
-inline MDBX_hsr_func *env::get_HandleSlowReaders() const noexcept {
-  return ::mdbx_env_get_hsr(handle_);
-}
-
-inline txn_managed env::start_read() const {
-  ::MDBX_txn *ptr;
-  error::success_or_throw(
-      ::mdbx_txn_begin(handle_, nullptr, MDBX_TXN_RDONLY, &ptr));
-  assert(ptr != nullptr);
-  return txn_managed(ptr);
-}
-
-inline txn_managed env::prepare_read() const {
-  ::MDBX_txn *ptr;
-  error::success_or_throw(
-      ::mdbx_txn_begin(handle_, nullptr, MDBX_TXN_RDONLY_PREPARE, &ptr));
-  assert(ptr != nullptr);
-  return txn_managed(ptr);
-}
-
-inline txn_managed env::start_write(bool dont_wait) {
-  ::MDBX_txn *ptr;
-  error::success_or_throw(::mdbx_txn_begin(
-      handle_, nullptr, dont_wait ? MDBX_TXN_TRY : MDBX_TXN_READWRITE, &ptr));
-  assert(ptr != nullptr);
-  return txn_managed(ptr);
-}
-
-inline txn_managed env::try_start_write() { return start_write(true); }
-
-//------------------------------------------------------------------------------
-
-MDBX_CXX11_CONSTEXPR txn::txn(MDBX_txn *ptr) noexcept : handle_(ptr) {}
-
-inline txn &txn::operator=(txn &&other) noexcept {
-  handle_ = other.handle_;
-  other.handle_ = nullptr;
-  return *this;
-}
-
-inline txn::txn(txn &&other) noexcept : handle_(other.handle_) {
-  other.handle_ = nullptr;
-}
-
-inline txn::~txn() noexcept {
-#ifndef NDEBUG
-  handle_ = reinterpret_cast<MDBX_txn *>(uintptr_t(0xDeadBeef));
-#endif
-}
-
-MDBX_CXX14_CONSTEXPR txn::operator bool() const noexcept {
-  return handle_ != nullptr;
-}
-
-MDBX_CXX14_CONSTEXPR txn::operator const MDBX_txn *() const { return handle_; }
-
-MDBX_CXX14_CONSTEXPR txn::operator MDBX_txn *() { return handle_; }
-
-MDBX_CXX11_CONSTEXPR bool operator==(const txn &a, const txn &b) noexcept {
-  return a.handle_ == b.handle_;
-}
-
-MDBX_CXX11_CONSTEXPR bool operator!=(const txn &a, const txn &b) noexcept {
-  return a.handle_ != b.handle_;
-}
-
-inline bool txn::is_dirty(const void *ptr) const {
-  int err = ::mdbx_is_dirty(handle_, ptr);
-  switch (err) {
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  case MDBX_RESULT_TRUE:
-    return true;
-  case MDBX_RESULT_FALSE:
-    return false;
-  }
-}
-
-inline ::mdbx::env txn::env() const noexcept { return ::mdbx_txn_env(handle_); }
-
-inline MDBX_txn_flags_t txn::flags() const {
-  const int bits = mdbx_txn_flags(handle_);
-  error::throw_on_failure((bits != -1) ? MDBX_SUCCESS : MDBX_BAD_TXN);
-  return static_cast<MDBX_txn_flags_t>(bits);
-}
-
-inline uint64_t txn::id() const {
-  const uint64_t txnid = mdbx_txn_id(handle_);
-  error::throw_on_failure(txnid ? MDBX_SUCCESS : MDBX_BAD_TXN);
-  return txnid;
-}
-
-inline void txn::reset_reading() {
-  error::success_or_throw(::mdbx_txn_reset(handle_));
-}
-
-inline void txn::renew_reading() {
-  error::success_or_throw(::mdbx_txn_renew(handle_));
-}
-
-inline txn::info txn::get_info(bool scan_reader_lock_table) const {
-  txn::info r;
-  error::success_or_throw(::mdbx_txn_info(handle_, &r, scan_reader_lock_table));
-  return r;
-}
-
-inline cursor_managed txn::open_cursor(map_handle map) {
-  MDBX_cursor *ptr;
-  error::success_or_throw(::mdbx_cursor_open(handle_, map.dbi, &ptr));
-  return cursor_managed(ptr);
-}
-
-inline ::mdbx::map_handle
-txn::open_map(const char *name, const ::mdbx::key_mode key_mode,
-              const ::mdbx::value_mode value_mode) const {
-  ::mdbx::map_handle map;
-  error::success_or_throw(::mdbx_dbi_open(
-      handle_, name, MDBX_db_flags_t(key_mode) | MDBX_db_flags_t(value_mode),
-      &map.dbi));
-  assert(map.dbi != 0);
-  return map;
-}
-
-inline ::mdbx::map_handle
-txn::open_map(const ::std::string &name, const ::mdbx::key_mode key_mode,
-              const ::mdbx::value_mode value_mode) const {
-  return open_map(name.c_str(), key_mode, value_mode);
-}
-
-inline ::mdbx::map_handle txn::create_map(const char *name,
-                                          const ::mdbx::key_mode key_mode,
-                                          const ::mdbx::value_mode value_mode) {
-  ::mdbx::map_handle map;
-  error::success_or_throw(::mdbx_dbi_open(
-      handle_, name,
-      MDBX_CREATE | MDBX_db_flags_t(key_mode) | MDBX_db_flags_t(value_mode),
-      &map.dbi));
-  assert(map.dbi != 0);
-  return map;
-}
-
-inline ::mdbx::map_handle txn::create_map(const ::std::string &name,
-                                          const ::mdbx::key_mode key_mode,
-                                          const ::mdbx::value_mode value_mode) {
-  return create_map(name.c_str(), key_mode, value_mode);
-}
-
-inline void txn::drop_map(map_handle map) {
-  error::success_or_throw(::mdbx_drop(handle_, map.dbi, true));
-}
-
-inline bool txn::drop_map(const ::std::string &name, bool throw_if_absent) {
-  return drop_map(name.c_str(), throw_if_absent);
-}
-
-inline void txn::clear_map(map_handle map) {
-  error::success_or_throw(::mdbx_drop(handle_, map.dbi, false));
-}
-
-inline bool txn::clear_map(const ::std::string &name, bool throw_if_absent) {
-  return clear_map(name.c_str(), throw_if_absent);
-}
-
-inline txn::map_stat txn::get_map_stat(map_handle map) const {
-  txn::map_stat r;
-  error::success_or_throw(::mdbx_dbi_stat(handle_, map.dbi, &r, sizeof(r)));
-  return r;
-}
-
-inline uint32_t txn::get_tree_deepmask(map_handle map) const {
-  uint32_t r;
-  error::success_or_throw(::mdbx_dbi_dupsort_depthmask(handle_, map.dbi, &r));
-  return r;
-}
-
-inline map_handle::info txn::get_handle_info(map_handle map) const {
-  unsigned flags, state;
-  error::success_or_throw(
-      ::mdbx_dbi_flags_ex(handle_, map.dbi, &flags, &state));
-  return map_handle::info(MDBX_db_flags_t(flags), MDBX_dbi_state_t(state));
-}
-
-inline txn &txn::put_canary(const txn::canary &canary) {
-  error::success_or_throw(::mdbx_canary_put(handle_, &canary));
-  return *this;
-}
-
-inline txn::canary txn::get_canary() const {
-  txn::canary r;
-  error::success_or_throw(::mdbx_canary_get(handle_, &r));
-  return r;
-}
-
-inline uint64_t txn::sequence(map_handle map) const {
-  uint64_t result;
-  error::success_or_throw(::mdbx_dbi_sequence(handle_, map.dbi, &result, 0));
-  return result;
-}
-
-inline uint64_t txn::sequence(map_handle map, uint64_t increment) {
-  uint64_t result;
-  error::success_or_throw(
-      ::mdbx_dbi_sequence(handle_, map.dbi, &result, increment));
-  return result;
-}
-
-inline int txn::compare_keys(map_handle map, const slice &a,
-                             const slice &b) const noexcept {
-  return ::mdbx_cmp(handle_, map.dbi, &a, &b);
-}
-
-inline int txn::compare_values(map_handle map, const slice &a,
-                               const slice &b) const noexcept {
-  return ::mdbx_dcmp(handle_, map.dbi, &a, &b);
-}
-
-inline int txn::compare_keys(map_handle map, const pair &a,
-                             const pair &b) const noexcept {
-  return compare_keys(map, a.key, b.key);
-}
-
-inline int txn::compare_values(map_handle map, const pair &a,
-                               const pair &b) const noexcept {
-  return compare_values(map, a.value, b.value);
-}
-
-inline slice txn::get(map_handle map, const slice &key) const {
-  slice result;
-  error::success_or_throw(::mdbx_get(handle_, map.dbi, &key, &result));
-  return result;
-}
-
-inline slice txn::get(map_handle map, slice key, size_t &values_count) const {
-  slice result;
-  error::success_or_throw(
-      ::mdbx_get_ex(handle_, map.dbi, &key, &result, &values_count));
-  return result;
-}
-
-inline slice txn::get(map_handle map, const slice &key,
-                      const slice &value_at_absence) const {
-  slice result;
-  const int err = ::mdbx_get(handle_, map.dbi, &key, &result);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return result;
-  case MDBX_NOTFOUND:
-    return value_at_absence;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline slice txn::get(map_handle map, slice key, size_t &values_count,
-                      const slice &value_at_absence) const {
-  slice result;
-  const int err = ::mdbx_get_ex(handle_, map.dbi, &key, &result, &values_count);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return result;
-  case MDBX_NOTFOUND:
-    return value_at_absence;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline pair_result txn::get_equal_or_great(map_handle map,
-                                           const slice &key) const {
-  pair result(key, slice());
-  bool exact = !error::boolean_or_throw(
-      ::mdbx_get_equal_or_great(handle_, map.dbi, &result.key, &result.value));
-  return pair_result(result.key, result.value, exact);
-}
-
-inline pair_result
-txn::get_equal_or_great(map_handle map, const slice &key,
-                        const slice &value_at_absence) const {
-  pair result{key, slice()};
-  const int err =
-      ::mdbx_get_equal_or_great(handle_, map.dbi, &result.key, &result.value);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return pair_result{result.key, result.value, true};
-  case MDBX_RESULT_TRUE:
-    return pair_result{result.key, result.value, false};
-  case MDBX_NOTFOUND:
-    return pair_result{key, value_at_absence, false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline MDBX_error_t txn::put(map_handle map, const slice &key, slice *value,
-                             MDBX_put_flags_t flags) noexcept {
-  return MDBX_error_t(::mdbx_put(handle_, map.dbi, &key, value, flags));
-}
-
-inline void txn::put(map_handle map, const slice &key, slice value,
-                     put_mode mode) noexcept {
-  error::success_or_throw(put(map, key, &value, MDBX_put_flags_t(mode)));
-}
-
-inline void txn::insert(map_handle map, const slice &key, slice value) {
-  error::success_or_throw(
-      put(map, key, &value /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique)));
-}
-
-inline value_result txn::try_insert(map_handle map, const slice &key,
-                                    slice value) {
-  const int err =
-      put(map, key, &value /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique));
-  switch (err) {
-  case MDBX_SUCCESS:
-    return value_result{slice(), true};
-  case MDBX_KEYEXIST:
-    return value_result{value, false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline slice txn::insert_reserve(map_handle map, const slice &key,
-                                 size_t value_length) {
-  slice result(nullptr, value_length);
-  error::success_or_throw(
-      put(map, key, &result /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique) | MDBX_RESERVE));
-  return result;
-}
-
-inline value_result txn::try_insert_reserve(map_handle map, const slice &key,
-                                            size_t value_length) {
-  slice result(nullptr, value_length);
-  const int err =
-      put(map, key, &result /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique) | MDBX_RESERVE);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return value_result{result, true};
-  case MDBX_KEYEXIST:
-    return value_result{result, false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline void txn::upsert(map_handle map, const slice &key, const slice &value) {
-  error::success_or_throw(put(map, key, const_cast<slice *>(&value),
-                              MDBX_put_flags_t(put_mode::upsert)));
-}
-
-inline slice txn::upsert_reserve(map_handle map, const slice &key,
-                                 size_t value_length) {
-  slice result(nullptr, value_length);
-  error::success_or_throw(put(
-      map, key, &result, MDBX_put_flags_t(put_mode::upsert) | MDBX_RESERVE));
-  return result;
-}
-
-inline void txn::update(map_handle map, const slice &key, const slice &value) {
-  error::success_or_throw(put(map, key, const_cast<slice *>(&value),
-                              MDBX_put_flags_t(put_mode::update)));
-}
-
-inline bool txn::try_update(map_handle map, const slice &key,
-                            const slice &value) {
-  const int err = put(map, key, const_cast<slice *>(&value),
-                      MDBX_put_flags_t(put_mode::update));
-  switch (err) {
-  case MDBX_SUCCESS:
-    return true;
-  case MDBX_NOTFOUND:
-    return false;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline slice txn::update_reserve(map_handle map, const slice &key,
-                                 size_t value_length) {
-  slice result(nullptr, value_length);
-  error::success_or_throw(put(
-      map, key, &result, MDBX_put_flags_t(put_mode::update) | MDBX_RESERVE));
-  return result;
-}
-
-inline value_result txn::try_update_reserve(map_handle map, const slice &key,
-                                            size_t value_length) {
-  slice result(nullptr, value_length);
-  const int err =
-      put(map, key, &result, MDBX_put_flags_t(put_mode::update) | MDBX_RESERVE);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return value_result{result, true};
-  case MDBX_NOTFOUND:
-    return value_result{slice(), false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline bool txn::erase(map_handle map, const slice &key) {
-  const int err = ::mdbx_del(handle_, map.dbi, &key, nullptr);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return true;
-  case MDBX_NOTFOUND:
-    return false;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline bool txn::erase(map_handle map, const slice &key, const slice &value) {
-  const int err = ::mdbx_del(handle_, map.dbi, &key, &value);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return true;
-  case MDBX_NOTFOUND:
-    return false;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline void txn::replace(map_handle map, const slice &key, slice old_value,
-                         const slice &new_value) {
-  error::success_or_throw(::mdbx_replace_ex(
-      handle_, map.dbi, &key, const_cast<slice *>(&new_value), &old_value,
-      MDBX_CURRENT | MDBX_NOOVERWRITE, nullptr, nullptr));
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR> txn::extract(map_handle map, const slice &key,
-                                      const ALLOCATOR &allocator) {
-  typename buffer<ALLOCATOR>::data_preserver result(allocator);
-  error::success_or_throw(::mdbx_replace_ex(handle_, map.dbi, &key, nullptr,
-                                            &result.slice_, MDBX_CURRENT,
-                                            result, &result),
-                          result);
-  return result;
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR> txn::replace(map_handle map, const slice &key,
-                                      const slice &new_value,
-                                      const ALLOCATOR &allocator) {
-  typename buffer<ALLOCATOR>::data_preserver result(allocator);
-  error::success_or_throw(
-      ::mdbx_replace_ex(handle_, map.dbi, &key, const_cast<slice *>(&new_value),
-                        &result.slice_, MDBX_CURRENT, result, &result),
-      result);
-  return result;
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR> txn::replace_reserve(map_handle map, const slice &key,
-                                              slice &new_value,
-                                              const ALLOCATOR &allocator) {
-  typename buffer<ALLOCATOR>::data_preserver result(allocator);
-  error::success_or_throw(
-      ::mdbx_replace_ex(handle_, map.dbi, &key, &new_value, &result.slice_,
-                        MDBX_CURRENT | MDBX_RESERVE, result, &result),
-      result);
-  return result;
-}
-
-inline void txn::append(map_handle map, const slice &key, const slice &value,
-                        bool multivalue_order_preserved) {
-  error::success_or_throw(::mdbx_put(
-      handle_, map.dbi, const_cast<slice *>(&key), const_cast<slice *>(&value),
-      multivalue_order_preserved ? (MDBX_APPEND | MDBX_APPENDDUP)
-                                 : MDBX_APPEND));
-}
-
-inline size_t txn::put_multiple(map_handle map, const slice &key,
-                                const size_t value_length,
-                                const void *values_array, size_t values_count,
-                                put_mode mode, bool allow_partial) {
-  MDBX_val args[2] = {{const_cast<void *>(values_array), value_length},
-                      {nullptr, values_count}};
-  const int err = ::mdbx_put(handle_, map.dbi, const_cast<slice *>(&key), args,
-                             MDBX_put_flags_t(mode) | MDBX_MULTIPLE);
-  switch (err) {
-  case MDBX_SUCCESS:
-    MDBX_CXX20_LIKELY break;
-  case MDBX_KEYEXIST:
-    if (allow_partial)
-      break;
-    mdbx_txn_break(handle_);
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-  return args[1].iov_len /* done item count */;
-}
-
-inline ptrdiff_t txn::estimate(map_handle map, pair from, pair to) const {
-  ptrdiff_t result;
-  error::success_or_throw(mdbx_estimate_range(
-      handle_, map.dbi, &from.key, &from.value, &to.key, &to.value, &result));
-  return result;
-}
-
-inline ptrdiff_t txn::estimate(map_handle map, slice from, slice to) const {
-  ptrdiff_t result;
-  error::success_or_throw(mdbx_estimate_range(handle_, map.dbi, &from, nullptr,
-                                              &to, nullptr, &result));
-  return result;
-}
-
-inline ptrdiff_t txn::estimate_from_first(map_handle map, slice to) const {
-  ptrdiff_t result;
-  error::success_or_throw(mdbx_estimate_range(handle_, map.dbi, nullptr,
-                                              nullptr, &to, nullptr, &result));
-  return result;
-}
-
-inline ptrdiff_t txn::estimate_to_last(map_handle map, slice from) const {
-  ptrdiff_t result;
-  error::success_or_throw(mdbx_estimate_range(handle_, map.dbi, &from, nullptr,
-                                              nullptr, nullptr, &result));
-  return result;
-}
-
-//------------------------------------------------------------------------------
-
-MDBX_CXX11_CONSTEXPR cursor::cursor(MDBX_cursor *ptr) noexcept : handle_(ptr) {}
-
-inline cursor &cursor::operator=(cursor &&other) noexcept {
-  handle_ = other.handle_;
-  other.handle_ = nullptr;
-  return *this;
-}
-
-inline cursor::cursor(cursor &&other) noexcept : handle_(other.handle_) {
-  other.handle_ = nullptr;
-}
-
-inline cursor::~cursor() noexcept {
-#ifndef NDEBUG
-  handle_ = reinterpret_cast<MDBX_cursor *>(uintptr_t(0xDeadBeef));
-#endif
-}
-
-MDBX_CXX14_CONSTEXPR cursor::operator bool() const noexcept {
-  return handle_ != nullptr;
-}
-
-MDBX_CXX14_CONSTEXPR cursor::operator const MDBX_cursor *() const {
-  return handle_;
-}
-
-MDBX_CXX14_CONSTEXPR cursor::operator MDBX_cursor *() { return handle_; }
-
-MDBX_CXX11_CONSTEXPR bool operator==(const cursor &a,
-                                     const cursor &b) noexcept {
-  return a.handle_ == b.handle_;
-}
-
-MDBX_CXX11_CONSTEXPR bool operator!=(const cursor &a,
-                                     const cursor &b) noexcept {
-  return a.handle_ != b.handle_;
-}
-
-inline cursor::move_result::move_result(const cursor &cursor,
-                                        bool throw_notfound)
-    : pair_result(key, value, false) {
-  done = cursor.move(get_current, &key, &value, throw_notfound);
-}
-
-inline cursor::move_result::move_result(cursor &cursor,
-                                        move_operation operation,
-                                        bool throw_notfound)
-    : pair_result(key, value, false) {
-  done = cursor.move(operation, &key, &value, throw_notfound);
-}
-
-inline cursor::move_result::move_result(cursor &cursor,
-                                        move_operation operation,
-                                        const slice &key, bool throw_notfound)
-    : pair_result(key, slice(), false) {
-  this->done = cursor.move(operation, &this->key, &this->value, throw_notfound);
-}
-
-inline cursor::move_result::move_result(cursor &cursor,
-                                        move_operation operation,
-                                        const slice &key, const slice &value,
-                                        bool throw_notfound)
-    : pair_result(key, value, false) {
-  this->done = cursor.move(operation, &this->key, &this->value, throw_notfound);
-}
-
-inline bool cursor::move(move_operation operation, MDBX_val *key,
-                         MDBX_val *value, bool throw_notfound) const {
-  const int err =
-      ::mdbx_cursor_get(handle_, key, value, MDBX_cursor_op(operation));
-  switch (err) {
-  case MDBX_SUCCESS:
-    MDBX_CXX20_LIKELY return true;
-  case MDBX_NOTFOUND:
-    if (!throw_notfound)
-      return false;
-    MDBX_CXX17_FALLTHROUGH /* fallthrough */;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline ptrdiff_t cursor::estimate(move_operation operation, MDBX_val *key,
-                                  MDBX_val *value) const {
-  ptrdiff_t result;
-  error::success_or_throw(::mdbx_estimate_move(
-      *this, key, value, MDBX_cursor_op(operation), &result));
-  return result;
-}
-
-inline ptrdiff_t estimate(const cursor &from, const cursor &to) {
-  ptrdiff_t result;
-  error::success_or_throw(mdbx_estimate_distance(from, to, &result));
-  return result;
-}
-
-inline cursor::move_result cursor::move(move_operation operation,
-                                        bool throw_notfound) {
-  return move_result(*this, operation, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_first(bool throw_notfound) {
-  return move(first, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_previous(bool throw_notfound) {
-  return move(previous, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_previous_last_multi(bool throw_notfound) {
-  return move(multi_prevkey_lastvalue, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_current_first_multi(bool throw_notfound) {
-  return move(multi_currentkey_firstvalue, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_current_prev_multi(bool throw_notfound) {
-  return move(multi_currentkey_prevvalue, throw_notfound);
-}
-
-inline cursor::move_result cursor::current(bool throw_notfound) const {
-  return move_result(*this, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_current_next_multi(bool throw_notfound) {
-  return move(multi_currentkey_nextvalue, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_current_last_multi(bool throw_notfound) {
-  return move(multi_currentkey_lastvalue, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_next_first_multi(bool throw_notfound) {
-  return move(multi_nextkey_firstvalue, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_next(bool throw_notfound) {
-  return move(next, throw_notfound);
-}
-
-inline cursor::move_result cursor::to_last(bool throw_notfound) {
-  return move(last, throw_notfound);
-}
-
-inline cursor::move_result cursor::move(move_operation operation,
-                                        const slice &key, bool throw_notfound) {
-  return move_result(*this, operation, key, throw_notfound);
-}
-
-inline cursor::move_result cursor::find(const slice &key, bool throw_notfound) {
-  return move(key_exact, key, throw_notfound);
-}
-
-inline cursor::move_result cursor::lower_bound(const slice &key,
-                                               bool throw_notfound) {
-  return move(key_lowerbound, key, throw_notfound);
-}
-
-inline cursor::move_result cursor::move(move_operation operation,
-                                        const slice &key, const slice &value,
-                                        bool throw_notfound) {
-  return move_result(*this, operation, key, value, throw_notfound);
-}
-
-inline cursor::move_result cursor::find_multivalue(const slice &key,
-                                                   const slice &value,
-                                                   bool throw_notfound) {
-  return move(key_exact, key, value, throw_notfound);
-}
-
-inline cursor::move_result cursor::lower_bound_multivalue(const slice &key,
-                                                          const slice &value,
-                                                          bool throw_notfound) {
-  return move(multi_exactkey_lowerboundvalue, key, value, throw_notfound);
-}
-
-inline bool cursor::seek(const slice &key) {
-  return move(find_key, const_cast<slice *>(&key), nullptr, false);
-}
-
-inline bool cursor::move(move_operation operation, slice &key, slice &value,
-                         bool throw_notfound) {
-  return move(operation, &key, &value, throw_notfound);
-}
-
-inline size_t cursor::count_multivalue() const {
-  size_t result;
-  error::success_or_throw(::mdbx_cursor_count(*this, &result));
-  return result;
-}
-
-inline bool cursor::eof() const {
-  return error::boolean_or_throw(::mdbx_cursor_eof(*this));
-}
-
-inline bool cursor::on_first() const {
-  return error::boolean_or_throw(::mdbx_cursor_on_first(*this));
-}
-
-inline bool cursor::on_last() const {
-  return error::boolean_or_throw(::mdbx_cursor_on_last(*this));
-}
-
-inline ptrdiff_t cursor::estimate(slice key, slice value) const {
-  return estimate(multi_exactkey_lowerboundvalue, &key, &value);
-}
-
-inline ptrdiff_t cursor::estimate(slice key) const {
-  return estimate(key_lowerbound, &key, nullptr);
-}
-
-inline ptrdiff_t cursor::estimate(move_operation operation) const {
-  slice unused_key;
-  return estimate(operation, &unused_key, nullptr);
-}
-
-inline void cursor::renew(::mdbx::txn &txn) {
-  error::success_or_throw(::mdbx_cursor_renew(txn, handle_));
-}
-
-inline void cursor::bind(::mdbx::txn &txn, ::mdbx::map_handle map_handle) {
-  error::success_or_throw(::mdbx_cursor_bind(txn, handle_, map_handle.dbi));
-}
-
-inline txn cursor::txn() const {
-  MDBX_txn *txn = ::mdbx_cursor_txn(handle_);
-  error::throw_on_nullptr(txn, MDBX_EINVAL);
-  return ::mdbx::txn(txn);
-}
-
-inline map_handle cursor::map() const {
-  const MDBX_dbi dbi = ::mdbx_cursor_dbi(handle_);
-  if (MDBX_UNLIKELY(dbi > MDBX_MAX_DBI))
-    error::throw_exception(MDBX_EINVAL);
-  return map_handle(dbi);
-}
-
-inline MDBX_error_t cursor::put(const slice &key, slice *value,
-                                MDBX_put_flags_t flags) noexcept {
-  return MDBX_error_t(::mdbx_cursor_put(handle_, &key, value, flags));
-}
-
-inline void cursor::insert(const slice &key, slice value) {
-  error::success_or_throw(
-      put(key, &value /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique)));
-}
-
-inline value_result cursor::try_insert(const slice &key, slice value) {
-  const int err =
-      put(key, &value /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique));
-  switch (err) {
-  case MDBX_SUCCESS:
-    return value_result{slice(), true};
-  case MDBX_KEYEXIST:
-    return value_result{value, false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline slice cursor::insert_reserve(const slice &key, size_t value_length) {
-  slice result(nullptr, value_length);
-  error::success_or_throw(
-      put(key, &result /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique) | MDBX_RESERVE));
-  return result;
-}
-
-inline value_result cursor::try_insert_reserve(const slice &key,
-                                               size_t value_length) {
-  slice result(nullptr, value_length);
-  const int err =
-      put(key, &result /* takes the present value in case MDBX_KEYEXIST */,
-          MDBX_put_flags_t(put_mode::insert_unique) | MDBX_RESERVE);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return value_result{result, true};
-  case MDBX_KEYEXIST:
-    return value_result{result, false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline void cursor::upsert(const slice &key, const slice &value) {
-  error::success_or_throw(put(key, const_cast<slice *>(&value),
-                              MDBX_put_flags_t(put_mode::upsert)));
-}
-
-inline slice cursor::upsert_reserve(const slice &key, size_t value_length) {
-  slice result(nullptr, value_length);
-  error::success_or_throw(
-      put(key, &result, MDBX_put_flags_t(put_mode::upsert) | MDBX_RESERVE));
-  return result;
-}
-
-inline void cursor::update(const slice &key, const slice &value) {
-  error::success_or_throw(put(key, const_cast<slice *>(&value),
-                              MDBX_put_flags_t(put_mode::update)));
-}
-
-inline bool cursor::try_update(const slice &key, const slice &value) {
-  const int err =
-      put(key, const_cast<slice *>(&value), MDBX_put_flags_t(put_mode::update));
-  switch (err) {
-  case MDBX_SUCCESS:
-    return true;
-  case MDBX_NOTFOUND:
-    return false;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline slice cursor::update_reserve(const slice &key, size_t value_length) {
-  slice result(nullptr, value_length);
-  error::success_or_throw(
-      put(key, &result, MDBX_put_flags_t(put_mode::update) | MDBX_RESERVE));
-  return result;
-}
-
-inline value_result cursor::try_update_reserve(const slice &key,
-                                               size_t value_length) {
-  slice result(nullptr, value_length);
-  const int err =
-      put(key, &result, MDBX_put_flags_t(put_mode::update) | MDBX_RESERVE);
-  switch (err) {
-  case MDBX_SUCCESS:
-    return value_result{result, true};
-  case MDBX_NOTFOUND:
-    return value_result{slice(), false};
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-inline bool cursor::erase(bool whole_multivalue) {
-  const int err = ::mdbx_cursor_del(handle_, whole_multivalue ? MDBX_ALLDUPS
-                                                              : MDBX_CURRENT);
-  switch (err) {
-  case MDBX_SUCCESS:
-    MDBX_CXX20_LIKELY return true;
-  case MDBX_NOTFOUND:
-    return false;
-  default:
-    MDBX_CXX20_UNLIKELY error::throw_exception(err);
-  }
-}
-
-//------------------------------------------------------------------------------
-
-inline cursor_managed::cursor_managed()
-    : cursor_managed(::mdbx_cursor_create(nullptr)) {
-  if (MDBX_UNLIKELY(!handle_))
-    MDBX_CXX20_UNLIKELY error::throw_exception(MDBX_ENOMEM);
-}
-
-//------------------------------------------------------------------------------
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR>::buffer(const txn &txn, const ::mdbx::slice &src,
-                                 const ALLOCATOR &allocator)
-    : buffer(src, !txn.is_dirty(src.data()), allocator) {}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR>::buffer(size_t head_room, size_t tail_room,
-                                 const ALLOCATOR &allocator)
-    : silo_(allocator) {
-  if (MDBX_UNLIKELY(head_room > max_length || tail_room > max_length ||
-                    head_room + tail_room > max_length))
-    throw_max_length_exceeded();
-  silo_.reserve(head_room + tail_room);
-  silo_.append(head_room, '\0');
-  slice_.iov_base = const_cast<char *>(silo_.data());
-  assert(slice_.iov_len == 0);
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR>::buffer(size_t capacity, const ALLOCATOR &allocator)
-    : silo_(allocator) {
-  silo_.reserve(check_length(capacity));
-  slice_.iov_base = const_cast<char *>(silo_.data());
-  assert(slice_.iov_len == 0);
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR>::buffer(size_t head_room, const ::mdbx::slice &src,
-                                 size_t tail_room, const ALLOCATOR &allocator)
-    : silo_(allocator) {
-  if (MDBX_UNLIKELY(head_room > max_length || tail_room > max_length ||
-                    head_room + tail_room > max_length - slice_.length()))
-    throw_max_length_exceeded();
-  silo_.reserve(head_room + src.length() + tail_room);
-  silo_.append(head_room, '\0');
-  silo_.append(src.char_ptr(), src.length());
-  slice_.iov_base = const_cast<char *>(silo_.data());
-  slice_.iov_len = src.length();
-}
-
-template <class ALLOCATOR>
-inline void buffer<ALLOCATOR>::reserve(size_t wanna_headroom,
-                                       size_t wanna_tailroom,
-                                       size_t shrink_threshold) {
-  if (MDBX_UNLIKELY(
-          wanna_headroom > max_length || wanna_tailroom > max_length ||
-          wanna_headroom + wanna_tailroom > max_length - slice_.length()))
-    throw_max_length_exceeded();
-
-  wanna_headroom = std::min(std::max(headroom(), wanna_headroom),
-                            wanna_headroom + shrink_threshold);
-  wanna_tailroom = std::min(std::max(tailroom(), wanna_tailroom),
-                            wanna_tailroom + shrink_threshold);
-  const auto wanna_capacity = wanna_headroom + slice_.length() + wanna_tailroom;
-  if (is_reference() || slice_.empty()) {
-    silo_.reserve(wanna_capacity);
-    silo_.resize(wanna_headroom);
-    silo_.append(slice_.char_ptr(), slice_.length());
-  } else {
-    const auto was_headroom = headroom();
-    if (was_headroom > wanna_headroom)
-      silo_.erase(wanna_headroom, was_headroom - wanna_headroom);
-    silo_.reserve(wanna_capacity);
-    if (was_headroom < wanna_headroom)
-      silo_.insert(was_headroom, wanna_headroom - was_headroom, '\0');
-  }
-  slice_.iov_base = const_cast<byte *>(silo_begin()) + wanna_headroom;
-  assert(headroom() >= wanna_headroom &&
-         headroom() <= wanna_headroom + shrink_threshold);
-  assert(tailroom() >= wanna_tailroom &&
-         tailroom() <= wanna_tailroom + shrink_threshold);
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR> &buffer<ALLOCATOR>::append(const void *src,
-                                                    size_t bytes) {
-  if (MDBX_UNLIKELY(tailroom() < check_length(bytes)))
-    reserve(0, bytes);
-  std::memcpy(static_cast<char *>(slice_.iov_base) + size(), src, bytes);
-  slice_.iov_len += bytes;
-  return *this;
-}
-
-template <class ALLOCATOR>
-inline buffer<ALLOCATOR> &buffer<ALLOCATOR>::add_header(const void *src,
-                                                        size_t bytes) {
-  if (MDBX_UNLIKELY(headroom() < check_length(bytes)))
-    reserve(bytes, 0);
-  slice_.iov_base =
-      std::memcpy(static_cast<char *>(slice_.iov_base) - bytes, src, bytes);
-  slice_.iov_len += bytes;
-  return *this;
-}
-
-template <class ALLOCATOR>
-inline void buffer<ALLOCATOR>::swap(buffer &other)
-#if defined(__cpp_noexcept_function_type) &&                                   \
-    __cpp_noexcept_function_type >= 201510L
-    noexcept(
-        std::allocator_traits<ALLOCATOR>::propagate_on_container_swap::value
-#if defined(__cpp_lib_allocator_traits_is_always_equal) &&                     \
-    __cpp_lib_allocator_traits_is_always_equal >= 201411L
-        || std::allocator_traits<ALLOCATOR>::is_always_equal::value
-#endif /* __cpp_lib_allocator_traits_is_always_equal */
-    )
-#endif /* __cpp_noexcept_function_type */
-{
-  if /* checking the equality of allocators to avoid UB */
-#if defined(__cpp_if_constexpr) && __cpp_if_constexpr >= 201606L
-      constexpr
-#endif
-      (!std::allocator_traits<ALLOCATOR>::propagate_on_container_swap::value
-#if defined(__cpp_lib_allocator_traits_is_always_equal) &&                     \
-    __cpp_lib_allocator_traits_is_always_equal >= 201411L
-       && !std::allocator_traits<ALLOCATOR>::is_always_equal::value
-#endif /* __cpp_lib_allocator_traits_is_always_equal */
-      ) {
-    if (MDBX_UNLIKELY(silo_.get_allocator() != other.silo_.get_allocator()))
-      throw std::bad_alloc();
-  }
-  silo_.swap(other.silo_);
-  slice_.swap(other.slice_);
-}
-
-template <class ALLOCATOR>
-inline int buffer<ALLOCATOR>::data_preserver::callback(void *context,
-                                                       MDBX_val *target,
-                                                       const void *src,
-                                                       size_t bytes) noexcept {
-  auto self = static_cast<data_preserver *>(context);
-  assert(self->is_clean());
-  assert(&self->data.slice_ == target);
-  (void)target;
-  try {
-    self->data.assign(src, bytes, false);
-    return MDBX_RESULT_FALSE;
-  } catch (... /* capture any exception to rethrow it over C code */) {
-    self->capture();
-    return MDBX_RESULT_TRUE;
-  }
-}
-
-} // namespace mdbx
-
-//------------------------------------------------------------------------------
-
-namespace std {
-
-inline string to_string(const mdbx::slice &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-template <class ALLOCATOR>
-inline string to_string(const mdbx::buffer<ALLOCATOR> &buffer) {
-  ostringstream out;
-  out << buffer;
-  return out.str();
-}
-
-inline string to_string(const mdbx::pair &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env::geometry &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env::operate_parameters &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env::mode &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env::durability &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env::reclaiming_options &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env::operate_options &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::env_managed::create_parameters &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const ::MDBX_log_level_t &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const ::MDBX_debug_flags_t &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const mdbx::error &value) {
-  ostringstream out;
-  out << value;
-  return out.str();
-}
-
-inline string to_string(const ::MDBX_error_t &errcode) {
-  return to_string(mdbx::error(errcode));
-}
-
-template <> struct hash<mdbx::slice> {
-  MDBX_CXX14_CONSTEXPR size_t
-  operator()(mdbx::slice const &slice) const noexcept {
-    return slice.hash_value();
-  }
-};
-} // namespace std
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-/// @} end of C++ API
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx_chk.c b/plugins/Dbx_mdbx/src/libmdbx/mdbx_chk.c
deleted file mode 100644
index a30003be28..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx_chk.c
+++ /dev/null
@@ -1,4818 +0,0 @@
-/* mdbx_chk.c - memory-mapped database check tool */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#ifdef _MSC_VER
-#if _MSC_VER > 1800
-#pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#pragma warning(disable : 4996) /* The POSIX name is deprecated... */
-#endif                          /* _MSC_VER (warnings) */
-
-#define MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-
-typedef struct flagbit {
-  int bit;
-  const char *name;
-} flagbit;
-
-const flagbit dbflags[] = {{MDBX_DUPSORT, "dupsort"},
-                           {MDBX_INTEGERKEY, "integerkey"},
-                           {MDBX_REVERSEKEY, "reversekey"},
-                           {MDBX_DUPFIXED, "dupfixed"},
-                           {MDBX_REVERSEDUP, "reversedup"},
-                           {MDBX_INTEGERDUP, "integerdup"},
-                           {0, nullptr}};
-
-#if defined(_WIN32) || defined(_WIN64)
-/*
- * POSIX getopt for Windows
- *
- * AT&T Public License
- *
- * Code given out at the 1985 UNIFORUM conference in Dallas.
- */
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#endif /* _MSC_VER (warnings) */
-
-#include <stdio.h>
-#include <string.h>
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-/*----------------------------------------------------------------------------*/
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-#ifndef EOF
-#define EOF (-1)
-#endif
-
-int optind = 1;
-int optopt;
-char *optarg;
-
-int getopt(int argc, char *const argv[], const char *opts) {
-  static int sp = 1;
-  int c;
-  const char *cp;
-
-  if (sp == 1) {
-    if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0')
-      return EOF;
-    else if (strcmp(argv[optind], "--") == 0) {
-      optind++;
-      return EOF;
-    }
-  }
-  optopt = c = argv[optind][sp];
-  if (c == ':' || (cp = strchr(opts, c)) == NULL) {
-    fprintf(stderr, "%s: %s -- %c\n", argv[0], "illegal option", c);
-    if (argv[optind][++sp] == '\0') {
-      optind++;
-      sp = 1;
-    }
-    return '?';
-  }
-  if (*++cp == ':') {
-    if (argv[optind][sp + 1] != '\0')
-      optarg = &argv[optind++][sp + 1];
-    else if (++optind >= argc) {
-      fprintf(stderr, "%s: %s -- %c\n", argv[0], "option requires an argument",
-              c);
-      sp = 1;
-      return '?';
-    } else
-      optarg = argv[optind++];
-    sp = 1;
-  } else {
-    if (argv[optind][++sp] == '\0') {
-      sp = 1;
-      optind++;
-    }
-    optarg = NULL;
-  }
-  return c;
-}
-
-static volatile BOOL user_break;
-static BOOL WINAPI ConsoleBreakHandlerRoutine(DWORD dwCtrlType) {
-  (void)dwCtrlType;
-  user_break = 1;
-  return true;
-}
-
-static uint64_t GetMilliseconds(void) {
-  LARGE_INTEGER Counter, Frequency;
-  return (QueryPerformanceFrequency(&Frequency) &&
-          QueryPerformanceCounter(&Counter))
-             ? Counter.QuadPart * 1000ul / Frequency.QuadPart
-             : 0;
-}
-
-#else /* WINDOWS */
-
-static volatile sig_atomic_t user_break;
-static void signal_handler(int sig) {
-  (void)sig;
-  user_break = 1;
-}
-
-#endif /* !WINDOWS */
-
-#define EXIT_INTERRUPTED (EXIT_FAILURE + 4)
-#define EXIT_FAILURE_SYS (EXIT_FAILURE + 3)
-#define EXIT_FAILURE_MDBX (EXIT_FAILURE + 2)
-#define EXIT_FAILURE_CHECK_MAJOR (EXIT_FAILURE + 1)
-#define EXIT_FAILURE_CHECK_MINOR EXIT_FAILURE
-
-typedef struct {
-  const char *name;
-  struct {
-    uint64_t branch, large_count, large_volume, leaf;
-    uint64_t subleaf_dupsort, leaf_dupfixed, subleaf_dupfixed;
-    uint64_t total, empty, other;
-  } pages;
-  uint64_t payload_bytes;
-  uint64_t lost_bytes;
-} walk_dbi_t;
-
-struct {
-  short *pagemap;
-  uint64_t total_payload_bytes;
-  uint64_t pgcount;
-  walk_dbi_t
-      dbi[MDBX_MAX_DBI + CORE_DBS + /* account pseudo-entry for meta */ 1];
-} walk;
-
-#define dbi_free walk.dbi[FREE_DBI]
-#define dbi_main walk.dbi[MAIN_DBI]
-#define dbi_meta walk.dbi[CORE_DBS]
-
-int envflags = MDBX_RDONLY | MDBX_EXCLUSIVE;
-MDBX_env *env;
-MDBX_txn *txn;
-MDBX_envinfo envinfo;
-MDBX_stat envstat;
-size_t userdb_count, skipped_subdb;
-uint64_t total_unused_bytes, reclaimable_pages, gc_pages, alloc_pages,
-    unused_pages, backed_pages;
-unsigned verbose;
-bool ignore_wrong_order, quiet, dont_traversal;
-const char *only_subdb;
-int stuck_meta = -1;
-
-struct problem {
-  struct problem *pr_next;
-  size_t count;
-  const char *caption;
-};
-
-struct problem *problems_list;
-uint64_t total_problems;
-
-static void MDBX_PRINTF_ARGS(1, 2) print(const char *msg, ...) {
-  if (!quiet) {
-    va_list args;
-
-    fflush(stderr);
-    va_start(args, msg);
-    vfprintf(stdout, msg, args);
-    va_end(args);
-  }
-}
-
-static void va_log(MDBX_log_level_t level, const char *msg, va_list args) {
-  static const char *const prefixes[] = {
-      "!!!fatal: ",       " ! " /* error */,      " ~ " /* warning */,
-      "   " /* notice */, "   // " /* verbose */, "   //// " /* debug */,
-      "   ////// " /* trace */
-  };
-
-  FILE *out = stdout;
-  if (level <= MDBX_LOG_ERROR) {
-    total_problems++;
-    out = stderr;
-  }
-
-  if (!quiet && verbose + 1 >= (unsigned)level) {
-    fflush(nullptr);
-    fputs(prefixes[level], out);
-    vfprintf(out, msg, args);
-    if (msg[strlen(msg) - 1] != '\n')
-      fputc('\n', out);
-    fflush(nullptr);
-  }
-
-  if (level == MDBX_LOG_FATAL) {
-    exit(EXIT_FAILURE_MDBX);
-    abort();
-  }
-}
-
-static void MDBX_PRINTF_ARGS(1, 2) error(const char *msg, ...) {
-  va_list args;
-  va_start(args, msg);
-  va_log(MDBX_LOG_ERROR, msg, args);
-  va_end(args);
-}
-
-static void logger(MDBX_log_level_t level, const char *function, int line,
-                   const char *msg, va_list args) {
-  (void)line;
-  (void)function;
-  if (level < MDBX_LOG_EXTRA)
-    va_log(level, msg, args);
-}
-
-static int check_user_break(void) {
-  switch (user_break) {
-  case 0:
-    return MDBX_SUCCESS;
-  case 1:
-    print(" - interrupted by signal\n");
-    fflush(nullptr);
-    user_break = 2;
-  }
-  return MDBX_EINTR;
-}
-
-static void pagemap_cleanup(void) {
-  for (size_t i = CORE_DBS + /* account pseudo-entry for meta */ 1;
-       i < ARRAY_LENGTH(walk.dbi); ++i) {
-    if (walk.dbi[i].name) {
-      mdbx_free((void *)walk.dbi[i].name);
-      walk.dbi[i].name = nullptr;
-    }
-  }
-
-  mdbx_free(walk.pagemap);
-  walk.pagemap = nullptr;
-}
-
-static walk_dbi_t *pagemap_lookup_dbi(const char *dbi_name, bool silent) {
-  static walk_dbi_t *last;
-
-  if (dbi_name == MDBX_PGWALK_MAIN)
-    return &dbi_main;
-  if (dbi_name == MDBX_PGWALK_GC)
-    return &dbi_free;
-  if (dbi_name == MDBX_PGWALK_META)
-    return &dbi_meta;
-
-  if (last && strcmp(last->name, dbi_name) == 0)
-    return last;
-
-  walk_dbi_t *dbi = walk.dbi + CORE_DBS + /* account pseudo-entry for meta */ 1;
-  for (; dbi < ARRAY_END(walk.dbi) && dbi->name; ++dbi) {
-    if (strcmp(dbi->name, dbi_name) == 0)
-      return last = dbi;
-  }
-
-  if (verbose > 0 && !silent) {
-    print(" - found '%s' area\n", dbi_name);
-    fflush(nullptr);
-  }
-
-  if (dbi == ARRAY_END(walk.dbi))
-    return nullptr;
-
-  dbi->name = mdbx_strdup(dbi_name);
-  return last = dbi;
-}
-
-static void MDBX_PRINTF_ARGS(4, 5)
-    problem_add(const char *object, uint64_t entry_number, const char *msg,
-                const char *extra, ...) {
-  total_problems++;
-
-  if (!quiet) {
-    int need_fflush = 0;
-    struct problem *p;
-
-    for (p = problems_list; p; p = p->pr_next)
-      if (p->caption == msg)
-        break;
-
-    if (!p) {
-      p = mdbx_calloc(1, sizeof(*p));
-      p->caption = msg;
-      p->pr_next = problems_list;
-      problems_list = p;
-      need_fflush = 1;
-    }
-
-    p->count++;
-    if (verbose > 1) {
-      print("     %s #%" PRIu64 ": %s", object, entry_number, msg);
-      if (extra) {
-        va_list args;
-        printf(" (");
-        va_start(args, extra);
-        vfprintf(stdout, extra, args);
-        va_end(args);
-        printf(")");
-      }
-      printf("\n");
-      if (need_fflush)
-        fflush(nullptr);
-    }
-  }
-}
-
-static struct problem *problems_push(void) {
-  struct problem *p = problems_list;
-  problems_list = nullptr;
-  return p;
-}
-
-static size_t problems_pop(struct problem *list) {
-  size_t count = 0;
-
-  if (problems_list) {
-    int i;
-
-    print(" - problems: ");
-    for (i = 0; problems_list; ++i) {
-      struct problem *p = problems_list->pr_next;
-      count += problems_list->count;
-      print("%s%s (%" PRIuPTR ")", i ? ", " : "", problems_list->caption,
-            problems_list->count);
-      mdbx_free(problems_list);
-      problems_list = p;
-    }
-    print("\n");
-    fflush(nullptr);
-  }
-
-  problems_list = list;
-  return count;
-}
-
-static int pgvisitor(const uint64_t pgno, const unsigned pgnumber,
-                     void *const ctx, const int deep,
-                     const char *const dbi_name_or_tag, const size_t page_size,
-                     const MDBX_page_type_t pagetype, const MDBX_error_t err,
-                     const size_t nentries, const size_t payload_bytes,
-                     const size_t header_bytes, const size_t unused_bytes) {
-  (void)ctx;
-  if (deep > 42) {
-    problem_add("deep", deep, "too large", nullptr);
-    return MDBX_CORRUPTED /* avoid infinite loop/recursion */;
-  }
-
-  walk_dbi_t *dbi = pagemap_lookup_dbi(dbi_name_or_tag, false);
-  if (!dbi)
-    return MDBX_ENOMEM;
-
-  const size_t page_bytes = payload_bytes + header_bytes + unused_bytes;
-  walk.pgcount += pgnumber;
-
-  const char *pagetype_caption;
-  bool branch = false;
-  switch (pagetype) {
-  default:
-    problem_add("page", pgno, "unknown page-type", "type %u, deep %i",
-                (unsigned)pagetype, deep);
-    pagetype_caption = "unknown";
-    dbi->pages.other += pgnumber;
-    break;
-  case MDBX_page_broken:
-    pagetype_caption = "broken";
-    dbi->pages.other += pgnumber;
-    break;
-  case MDBX_subpage_broken:
-    pagetype_caption = "broken-subpage";
-    break;
-  case MDBX_page_meta:
-    pagetype_caption = "meta";
-    dbi->pages.other += pgnumber;
-    break;
-  case MDBX_page_large:
-    pagetype_caption = "large";
-    dbi->pages.large_volume += pgnumber;
-    dbi->pages.large_count += 1;
-    break;
-  case MDBX_page_branch:
-    pagetype_caption = "branch";
-    dbi->pages.branch += pgnumber;
-    branch = true;
-    break;
-  case MDBX_page_leaf:
-    pagetype_caption = "leaf";
-    dbi->pages.leaf += pgnumber;
-    break;
-  case MDBX_page_dupfixed_leaf:
-    pagetype_caption = "leaf-dupfixed";
-    dbi->pages.leaf_dupfixed += pgnumber;
-    break;
-  case MDBX_subpage_leaf:
-    pagetype_caption = "subleaf-dupsort";
-    dbi->pages.subleaf_dupsort += 1;
-    break;
-  case MDBX_subpage_dupfixed_leaf:
-    pagetype_caption = "subleaf-dupfixed";
-    dbi->pages.subleaf_dupfixed += 1;
-    break;
-  }
-
-  if (pgnumber) {
-    if (verbose > 3 && (!only_subdb || strcmp(only_subdb, dbi->name) == 0)) {
-      if (pgnumber == 1)
-        print("     %s-page %" PRIu64, pagetype_caption, pgno);
-      else
-        print("     %s-span %" PRIu64 "[%u]", pagetype_caption, pgno, pgnumber);
-      print(" of %s: header %" PRIiPTR ", payload %" PRIiPTR
-            ", unused %" PRIiPTR ", deep %i\n",
-            dbi->name, header_bytes, payload_bytes, unused_bytes, deep);
-    }
-
-    bool already_used = false;
-    for (unsigned n = 0; n < pgnumber; ++n) {
-      uint64_t spanpgno = pgno + n;
-      if (spanpgno >= alloc_pages)
-        problem_add("page", spanpgno, "wrong page-no",
-                    "%s-page: %" PRIu64 " > %" PRIu64 ", deep %i",
-                    pagetype_caption, spanpgno, alloc_pages, deep);
-      else if (walk.pagemap[spanpgno]) {
-        walk_dbi_t *coll_dbi = &walk.dbi[walk.pagemap[spanpgno] - 1];
-        problem_add("page", spanpgno,
-                    (branch && coll_dbi == dbi) ? "loop" : "already used",
-                    "%s-page: by %s, deep %i", pagetype_caption, coll_dbi->name,
-                    deep);
-        already_used = true;
-      } else {
-        walk.pagemap[spanpgno] = (short)(dbi - walk.dbi + 1);
-        dbi->pages.total += 1;
-      }
-    }
-
-    if (already_used)
-      return branch ? MDBX_RESULT_TRUE /* avoid infinite loop/recursion */
-                    : MDBX_SUCCESS;
-  }
-
-  if (MDBX_IS_ERROR(err)) {
-    problem_add("page", pgno, "invalid/corrupted", "%s-page", pagetype_caption);
-  } else {
-    if (unused_bytes > page_size)
-      problem_add("page", pgno, "illegal unused-bytes",
-                  "%s-page: %u < %" PRIuPTR " < %u", pagetype_caption, 0,
-                  unused_bytes, envstat.ms_psize);
-
-    if (header_bytes < (int)sizeof(long) ||
-        (size_t)header_bytes >= envstat.ms_psize - sizeof(long))
-      problem_add("page", pgno, "illegal header-length",
-                  "%s-page: %" PRIuPTR " < %" PRIuPTR " < %" PRIuPTR,
-                  pagetype_caption, sizeof(long), header_bytes,
-                  envstat.ms_psize - sizeof(long));
-    if (payload_bytes < 1) {
-      if (nentries > 1) {
-        problem_add("page", pgno, "zero size-of-entry",
-                    "%s-page: payload %" PRIuPTR " bytes, %" PRIuPTR " entries",
-                    pagetype_caption, payload_bytes, nentries);
-        /* if ((size_t)header_bytes + unused_bytes < page_size) {
-          // LY: hush a misuse error
-          page_bytes = page_size;
-        } */
-      } else {
-        problem_add("page", pgno, "empty",
-                    "%s-page: payload %" PRIuPTR " bytes, %" PRIuPTR
-                    " entries, deep %i",
-                    pagetype_caption, payload_bytes, nentries, deep);
-        dbi->pages.empty += 1;
-      }
-    }
-
-    if (pgnumber) {
-      if (page_bytes != page_size) {
-        problem_add("page", pgno, "misused",
-                    "%s-page: %" PRIuPTR " != %" PRIuPTR " (%" PRIuPTR
-                    "h + %" PRIuPTR "p + %" PRIuPTR "u), deep %i",
-                    pagetype_caption, page_size, page_bytes, header_bytes,
-                    payload_bytes, unused_bytes, deep);
-        if (page_size > page_bytes)
-          dbi->lost_bytes += page_size - page_bytes;
-      } else {
-        dbi->payload_bytes += payload_bytes + header_bytes;
-        walk.total_payload_bytes += payload_bytes + header_bytes;
-      }
-    }
-  }
-
-  return check_user_break();
-}
-
-typedef int(visitor)(const uint64_t record_number, const MDBX_val *key,
-                     const MDBX_val *data);
-static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
-                      bool silent);
-
-static int handle_userdb(const uint64_t record_number, const MDBX_val *key,
-                         const MDBX_val *data) {
-  (void)record_number;
-  (void)key;
-  (void)data;
-  return check_user_break();
-}
-
-static int handle_freedb(const uint64_t record_number, const MDBX_val *key,
-                         const MDBX_val *data) {
-  char *bad = "";
-  pgno_t *iptr = data->iov_base;
-
-  if (key->iov_len != sizeof(txnid_t))
-    problem_add("entry", record_number, "wrong txn-id size",
-                "key-size %" PRIiPTR, key->iov_len);
-  else {
-    txnid_t txnid;
-    memcpy(&txnid, key->iov_base, sizeof(txnid));
-    if (txnid < 1 || txnid > envinfo.mi_recent_txnid)
-      problem_add("entry", record_number, "wrong txn-id", "%" PRIaTXN, txnid);
-    else {
-      if (data->iov_len < sizeof(pgno_t) || data->iov_len % sizeof(pgno_t))
-        problem_add("entry", txnid, "wrong idl size", "%" PRIuPTR,
-                    data->iov_len);
-      size_t number = (data->iov_len >= sizeof(pgno_t)) ? *iptr++ : 0;
-      if (number < 1 || number > MDBX_PGL_LIMIT)
-        problem_add("entry", txnid, "wrong idl length", "%" PRIuPTR, number);
-      else if ((number + 1) * sizeof(pgno_t) > data->iov_len) {
-        problem_add("entry", txnid, "trimmed idl",
-                    "%" PRIuSIZE " > %" PRIuSIZE " (corruption)",
-                    (number + 1) * sizeof(pgno_t), data->iov_len);
-        number = data->iov_len / sizeof(pgno_t) - 1;
-      } else if (data->iov_len - (number + 1) * sizeof(pgno_t) >=
-                 /* LY: allow gap up to one page. it is ok
-                  * and better than shink-and-retry inside mdbx_update_gc() */
-                 envstat.ms_psize)
-        problem_add("entry", txnid, "extra idl space",
-                    "%" PRIuSIZE " < %" PRIuSIZE " (minor, not a trouble)",
-                    (number + 1) * sizeof(pgno_t), data->iov_len);
-
-      gc_pages += number;
-      if (envinfo.mi_latter_reader_txnid > txnid)
-        reclaimable_pages += number;
-
-      pgno_t prev = MDBX_PNL_ASCENDING ? NUM_METAS - 1 : txn->mt_next_pgno;
-      pgno_t span = 1;
-      for (unsigned i = 0; i < number; ++i) {
-        if (check_user_break())
-          return MDBX_EINTR;
-        const pgno_t pgno = iptr[i];
-        if (pgno < NUM_METAS)
-          problem_add("entry", txnid, "wrong idl entry",
-                      "pgno %" PRIaPGNO " < meta-pages %u", pgno, NUM_METAS);
-        else if (pgno >= backed_pages)
-          problem_add("entry", txnid, "wrong idl entry",
-                      "pgno %" PRIaPGNO " > backed-pages %" PRIu64, pgno,
-                      backed_pages);
-        else if (pgno >= alloc_pages)
-          problem_add("entry", txnid, "wrong idl entry",
-                      "pgno %" PRIaPGNO " > alloc-pages %" PRIu64, pgno,
-                      alloc_pages - 1);
-        else {
-          if (MDBX_PNL_DISORDERED(prev, pgno)) {
-            bad = " [bad sequence]";
-            problem_add("entry", txnid, "bad sequence",
-                        "%" PRIaPGNO " %c [%u].%" PRIaPGNO, prev,
-                        (prev == pgno) ? '=' : (MDBX_PNL_ASCENDING ? '>' : '<'),
-                        i, pgno);
-          }
-          if (walk.pagemap) {
-            int idx = walk.pagemap[pgno];
-            if (idx == 0)
-              walk.pagemap[pgno] = -1;
-            else if (idx > 0)
-              problem_add("page", pgno, "already used", "by %s",
-                          walk.dbi[idx - 1].name);
-            else
-              problem_add("page", pgno, "already listed in GC", nullptr);
-          }
-        }
-        prev = pgno;
-        while (i + span < number &&
-               iptr[i + span] == (MDBX_PNL_ASCENDING ? pgno_add(pgno, span)
-                                                     : pgno_sub(pgno, span)))
-          ++span;
-      }
-      if (verbose > 3 && !only_subdb) {
-        print("     transaction %" PRIaTXN ", %" PRIuPTR
-              " pages, maxspan %" PRIaPGNO "%s\n",
-              txnid, number, span, bad);
-        if (verbose > 4) {
-          for (unsigned i = 0; i < number; i += span) {
-            const pgno_t pgno = iptr[i];
-            for (span = 1;
-                 i + span < number &&
-                 iptr[i + span] == (MDBX_PNL_ASCENDING ? pgno_add(pgno, span)
-                                                       : pgno_sub(pgno, span));
-                 ++span)
-              ;
-            if (span > 1) {
-              print("    %9" PRIaPGNO "[%" PRIaPGNO "]\n", pgno, span);
-            } else
-              print("    %9" PRIaPGNO "\n", pgno);
-          }
-        }
-      }
-    }
-  }
-
-  return check_user_break();
-}
-
-static int equal_or_greater(const MDBX_val *a, const MDBX_val *b) {
-  return (a->iov_len == b->iov_len &&
-          memcmp(a->iov_base, b->iov_base, a->iov_len) == 0)
-             ? 0
-             : 1;
-}
-
-static int handle_maindb(const uint64_t record_number, const MDBX_val *key,
-                         const MDBX_val *data) {
-  char *name;
-  int rc;
-  size_t i;
-
-  name = key->iov_base;
-  for (i = 0; i < key->iov_len; ++i) {
-    if (name[i] < ' ')
-      return handle_userdb(record_number, key, data);
-  }
-
-  name = mdbx_malloc(key->iov_len + 1);
-  memcpy(name, key->iov_base, key->iov_len);
-  name[key->iov_len] = '\0';
-  userdb_count++;
-
-  rc = process_db(~0u, name, handle_userdb, false);
-  mdbx_free(name);
-  if (rc != MDBX_INCOMPATIBLE)
-    return rc;
-
-  return handle_userdb(record_number, key, data);
-}
-
-static const char *db_flags2keymode(unsigned flags) {
-  flags &= (MDBX_REVERSEKEY | MDBX_INTEGERKEY);
-  switch (flags) {
-  case 0:
-    return "usual";
-  case MDBX_REVERSEKEY:
-    return "reserve";
-  case MDBX_INTEGERKEY:
-    return "ordinal";
-  case MDBX_REVERSEKEY | MDBX_INTEGERKEY:
-    return "msgpack";
-  default:
-    assert(false);
-    __unreachable();
-  }
-}
-
-static const char *db_flags2valuemode(unsigned flags) {
-  flags &= (MDBX_DUPSORT | MDBX_REVERSEDUP | MDBX_DUPFIXED | MDBX_INTEGERDUP);
-  switch (flags) {
-  case 0:
-    return "single";
-  case MDBX_DUPSORT:
-    return "multi";
-  case MDBX_REVERSEDUP:
-  case MDBX_DUPSORT | MDBX_REVERSEDUP:
-    return "multi-reverse";
-  case MDBX_DUPFIXED:
-  case MDBX_DUPSORT | MDBX_DUPFIXED:
-    return "multi-samelength";
-  case MDBX_DUPFIXED | MDBX_REVERSEDUP:
-  case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_REVERSEDUP:
-    return "multi-reverse-samelength";
-  case MDBX_INTEGERDUP:
-  case MDBX_DUPSORT | MDBX_INTEGERDUP:
-  case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP:
-  case MDBX_DUPFIXED | MDBX_INTEGERDUP:
-    return "multi-ordinal";
-  case MDBX_INTEGERDUP | MDBX_REVERSEDUP:
-  case MDBX_DUPSORT | MDBX_INTEGERDUP | MDBX_REVERSEDUP:
-    return "multi-msgpack";
-  case MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP:
-  case MDBX_DUPSORT | MDBX_DUPFIXED | MDBX_INTEGERDUP | MDBX_REVERSEDUP:
-    return "reserved";
-  default:
-    assert(false);
-    __unreachable();
-  }
-}
-
-static int process_db(MDBX_dbi dbi_handle, char *dbi_name, visitor *handler,
-                      bool silent) {
-  MDBX_cursor *mc;
-  MDBX_stat ms;
-  MDBX_val key, data;
-  MDBX_val prev_key, prev_data;
-  unsigned flags;
-  int rc, i;
-  struct problem *saved_list;
-  uint64_t problems_count;
-
-  uint64_t record_count = 0, dups = 0;
-  uint64_t key_bytes = 0, data_bytes = 0;
-
-  if ((MDBX_TXN_FINISHED | MDBX_TXN_ERROR) & mdbx_txn_flags(txn)) {
-    print(" ! abort processing '%s' due to a previous error\n",
-          dbi_name ? dbi_name : "@MAIN");
-    return MDBX_BAD_TXN;
-  }
-
-  if (dbi_handle == ~0u) {
-    rc = mdbx_dbi_open_ex(
-        txn, dbi_name, MDBX_DB_ACCEDE, &dbi_handle,
-        (dbi_name && ignore_wrong_order) ? equal_or_greater : nullptr,
-        (dbi_name && ignore_wrong_order) ? equal_or_greater : nullptr);
-    if (rc) {
-      if (!dbi_name ||
-          rc !=
-              MDBX_INCOMPATIBLE) /* LY: mainDB's record is not a user's DB. */ {
-        error("mdbx_open '%s' failed, error %d %s\n",
-              dbi_name ? dbi_name : "main", rc, mdbx_strerror(rc));
-      }
-      return rc;
-    }
-  }
-
-  if (dbi_handle >= CORE_DBS && dbi_name && only_subdb &&
-      strcmp(only_subdb, dbi_name) != 0) {
-    if (verbose) {
-      print("Skip processing '%s'...\n", dbi_name);
-      fflush(nullptr);
-    }
-    skipped_subdb++;
-    return MDBX_SUCCESS;
-  }
-
-  if (!silent && verbose) {
-    print("Processing '%s'...\n", dbi_name ? dbi_name : "@MAIN");
-    fflush(nullptr);
-  }
-
-  rc = mdbx_dbi_flags(txn, dbi_handle, &flags);
-  if (rc) {
-    error("mdbx_dbi_flags failed, error %d %s\n", rc, mdbx_strerror(rc));
-    return rc;
-  }
-
-  rc = mdbx_dbi_stat(txn, dbi_handle, &ms, sizeof(ms));
-  if (rc) {
-    error("mdbx_dbi_stat failed, error %d %s\n", rc, mdbx_strerror(rc));
-    return rc;
-  }
-
-  if (!silent && verbose) {
-    print(" - key-value kind: %s-key => %s-value", db_flags2keymode(flags),
-          db_flags2valuemode(flags));
-    if (verbose > 1) {
-      print(", flags:");
-      if (!flags)
-        print(" none");
-      else {
-        for (i = 0; dbflags[i].bit; i++)
-          if (flags & dbflags[i].bit)
-            print(" %s", dbflags[i].name);
-      }
-      if (verbose > 2)
-        print(" (0x%02X), dbi-id %d", flags, dbi_handle);
-    }
-    print("\n");
-    if (ms.ms_mod_txnid)
-      print(" - last modification txn#%" PRIu64 "\n", ms.ms_mod_txnid);
-    if (verbose > 1) {
-      print(" - page size %u, entries %" PRIu64 "\n", ms.ms_psize,
-            ms.ms_entries);
-      print(" - b-tree depth %u, pages: branch %" PRIu64 ", leaf %" PRIu64
-            ", overflow %" PRIu64 "\n",
-            ms.ms_depth, ms.ms_branch_pages, ms.ms_leaf_pages,
-            ms.ms_overflow_pages);
-    }
-  }
-
-  walk_dbi_t *dbi = (dbi_handle < CORE_DBS)
-                        ? &walk.dbi[dbi_handle]
-                        : pagemap_lookup_dbi(dbi_name, true);
-  if (!dbi) {
-    error("too many DBIs or out of memory\n");
-    return MDBX_ENOMEM;
-  }
-  if (!dont_traversal) {
-    const uint64_t subtotal_pages =
-        ms.ms_branch_pages + ms.ms_leaf_pages + ms.ms_overflow_pages;
-    if (subtotal_pages != dbi->pages.total)
-      error("%s pages mismatch (%" PRIu64 " != walked %" PRIu64 ")\n",
-            "subtotal", subtotal_pages, dbi->pages.total);
-    if (ms.ms_branch_pages != dbi->pages.branch)
-      error("%s pages mismatch (%" PRIu64 " != walked %" PRIu64 ")\n", "branch",
-            ms.ms_branch_pages, dbi->pages.branch);
-    const uint64_t allleaf_pages = dbi->pages.leaf + dbi->pages.leaf_dupfixed;
-    if (ms.ms_leaf_pages != allleaf_pages)
-      error("%s pages mismatch (%" PRIu64 " != walked %" PRIu64 ")\n",
-            "all-leaf", ms.ms_leaf_pages, allleaf_pages);
-    if (ms.ms_overflow_pages != dbi->pages.large_volume)
-      error("%s pages mismatch (%" PRIu64 " != walked %" PRIu64 ")\n",
-            "large/overlow", ms.ms_overflow_pages, dbi->pages.large_volume);
-  }
-  rc = mdbx_cursor_open(txn, dbi_handle, &mc);
-  if (rc) {
-    error("mdbx_cursor_open failed, error %d %s\n", rc, mdbx_strerror(rc));
-    return rc;
-  }
-
-  if (ignore_wrong_order) { /* for debugging with enabled assertions */
-    mc->mc_flags |= C_SKIPORD;
-    if (mc->mc_xcursor)
-      mc->mc_xcursor->mx_cursor.mc_flags |= C_SKIPORD;
-  }
-
-  const size_t maxkeysize = mdbx_env_get_maxkeysize_ex(env, flags);
-  saved_list = problems_push();
-  prev_key.iov_base = nullptr;
-  prev_key.iov_len = 0;
-  prev_data.iov_base = nullptr;
-  prev_data.iov_len = 0;
-  rc = mdbx_cursor_get(mc, &key, &data, MDBX_FIRST);
-  while (rc == MDBX_SUCCESS) {
-    rc = check_user_break();
-    if (rc)
-      goto bailout;
-
-    bool bad_key = false;
-    if (key.iov_len > maxkeysize) {
-      problem_add("entry", record_count, "key length exceeds max-key-size",
-                  "%" PRIuPTR " > %" PRIuPTR, key.iov_len, maxkeysize);
-      bad_key = true;
-    } else if ((flags & MDBX_INTEGERKEY) && key.iov_len != sizeof(uint64_t) &&
-               key.iov_len != sizeof(uint32_t)) {
-      problem_add("entry", record_count, "wrong key length",
-                  "%" PRIuPTR " != 4or8", key.iov_len);
-      bad_key = true;
-    }
-
-    bool bad_data = false;
-    if ((flags & MDBX_INTEGERDUP) && data.iov_len != sizeof(uint64_t) &&
-        data.iov_len != sizeof(uint32_t)) {
-      problem_add("entry", record_count, "wrong data length",
-                  "%" PRIuPTR " != 4or8", data.iov_len);
-      bad_data = true;
-    }
-
-    if (prev_key.iov_base && !bad_data) {
-      if ((flags & MDBX_DUPFIXED) && prev_data.iov_len != data.iov_len) {
-        problem_add("entry", record_count, "different data length",
-                    "%" PRIuPTR " != %" PRIuPTR, prev_data.iov_len,
-                    data.iov_len);
-        bad_data = true;
-      }
-
-      if (!bad_key) {
-        int cmp = mdbx_cmp(txn, dbi_handle, &key, &prev_key);
-        if (cmp == 0) {
-          ++dups;
-          if ((flags & MDBX_DUPSORT) == 0) {
-            problem_add("entry", record_count, "duplicated entries", nullptr);
-            if (data.iov_len == prev_data.iov_len &&
-                memcmp(data.iov_base, prev_data.iov_base, data.iov_len) == 0) {
-              problem_add("entry", record_count, "complete duplicate", nullptr);
-            }
-          } else if (!bad_data) {
-            cmp = mdbx_dcmp(txn, dbi_handle, &data, &prev_data);
-            if (cmp == 0) {
-              problem_add("entry", record_count, "complete duplicate", nullptr);
-            } else if (cmp < 0 && !ignore_wrong_order) {
-              problem_add("entry", record_count, "wrong order of multi-values",
-                          nullptr);
-            }
-          }
-        } else if (cmp < 0 && !ignore_wrong_order) {
-          problem_add("entry", record_count, "wrong order of entries", nullptr);
-        }
-      }
-    } else if (verbose) {
-      if (flags & MDBX_INTEGERKEY)
-        print(" - fixed key-size %" PRIuPTR "\n", key.iov_len);
-      if (flags & (MDBX_INTEGERDUP | MDBX_DUPFIXED))
-        print(" - fixed data-size %" PRIuPTR "\n", data.iov_len);
-    }
-
-    if (handler) {
-      rc = handler(record_count, &key, &data);
-      if (MDBX_IS_ERROR(rc))
-        goto bailout;
-    }
-
-    record_count++;
-    key_bytes += key.iov_len;
-    data_bytes += data.iov_len;
-
-    if (!bad_key)
-      prev_key = key;
-    if (!bad_data)
-      prev_data = data;
-    rc = mdbx_cursor_get(mc, &key, &data, MDBX_NEXT);
-  }
-  if (rc != MDBX_NOTFOUND)
-    error("mdbx_cursor_get failed, error %d %s\n", rc, mdbx_strerror(rc));
-  else
-    rc = 0;
-
-  if (record_count != ms.ms_entries)
-    problem_add("entry", record_count, "different number of entries",
-                "%" PRIu64 " != %" PRIu64, record_count, ms.ms_entries);
-bailout:
-  problems_count = problems_pop(saved_list);
-  if (!silent && verbose) {
-    print(" - summary: %" PRIu64 " records, %" PRIu64 " dups, %" PRIu64
-          " key's bytes, %" PRIu64 " data's "
-          "bytes, %" PRIu64 " problems\n",
-          record_count, dups, key_bytes, data_bytes, problems_count);
-    fflush(nullptr);
-  }
-
-  mdbx_cursor_close(mc);
-  return (rc || problems_count) ? MDBX_RESULT_TRUE : MDBX_SUCCESS;
-}
-
-static void usage(char *prog) {
-  fprintf(stderr,
-          "usage: %s [-V] [-v] [-q] [-c] [-0|1|2] [-w] [-d] [-i] [-s subdb] "
-          "dbpath\n"
-          "  -V\t\tprint version and exit\n"
-          "  -v\t\tmore verbose, could be used multiple times\n"
-          "  -q\t\tbe quiet\n"
-          "  -c\t\tforce cooperative mode (don't try exclusive)\n"
-          "  -w\t\twrite-mode checking\n"
-          "  -d\t\tdisable page-by-page traversal of B-tree\n"
-          "  -i\t\tignore wrong order errors (for custom comparators case)\n"
-          "  -s subdb\tprocess a specific subdatabase only\n"
-          "  -0|1|2\tforce using specific meta-page 0, or 2 for checking\n"
-          "  -t\t\tturn to a specified meta-page on successful check\n"
-          "  -T\t\tturn to a specified meta-page EVEN ON UNSUCCESSFUL CHECK!\n",
-          prog);
-  exit(EXIT_INTERRUPTED);
-}
-
-static __inline bool meta_ot(txnid_t txn_a, uint64_t sign_a, txnid_t txn_b,
-                             uint64_t sign_b, const bool wanna_steady) {
-  if (txn_a == txn_b)
-    return SIGN_IS_STEADY(sign_b);
-
-  if (wanna_steady && SIGN_IS_STEADY(sign_a) != SIGN_IS_STEADY(sign_b))
-    return SIGN_IS_STEADY(sign_b);
-
-  return txn_a < txn_b;
-}
-
-static __inline bool meta_eq(txnid_t txn_a, uint64_t sign_a, txnid_t txn_b,
-                             uint64_t sign_b) {
-  if (txn_a != txn_b)
-    return false;
-
-  if (SIGN_IS_STEADY(sign_a) != SIGN_IS_STEADY(sign_b))
-    return false;
-
-  return true;
-}
-
-static __inline int meta_recent(const bool wanna_steady) {
-  if (meta_ot(envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign,
-              envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign, wanna_steady))
-    return meta_ot(envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign,
-                   envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign, wanna_steady)
-               ? 1
-               : 2;
-  else
-    return meta_ot(envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign,
-                   envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign, wanna_steady)
-               ? 2
-               : 0;
-}
-
-static __inline int meta_tail(int head) {
-  switch (head) {
-  case 0:
-    return meta_ot(envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign,
-                   envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign, true)
-               ? 1
-               : 2;
-  case 1:
-    return meta_ot(envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign,
-                   envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign, true)
-               ? 0
-               : 2;
-  case 2:
-    return meta_ot(envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign,
-                   envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign, true)
-               ? 0
-               : 1;
-  default:
-    assert(false);
-    return -1;
-  }
-}
-
-static int meta_head(void) { return meta_recent(false); }
-
-void verbose_meta(int num, txnid_t txnid, uint64_t sign, uint64_t bootid_x,
-                  uint64_t bootid_y) {
-  const bool have_bootid = (bootid_x | bootid_y) != 0;
-  const bool bootid_match = bootid_x == envinfo.mi_bootid.current.x &&
-                            bootid_y == envinfo.mi_bootid.current.y;
-
-  print(" - meta-%d: ", num);
-  switch (sign) {
-  case MDBX_DATASIGN_NONE:
-    print("no-sync/legacy");
-    break;
-  case MDBX_DATASIGN_WEAK:
-    print("weak-%s", bootid_match ? (have_bootid ? "intact (same boot-id)"
-                                                 : "unknown (no boot-id")
-                                  : "dead");
-    break;
-  default:
-    print("steady");
-    break;
-  }
-  print(" txn#%" PRIu64, txnid);
-
-  const int head = meta_head();
-  if (num == head)
-    print(", head");
-  else if (num == meta_tail(head))
-    print(", tail");
-  else
-    print(", stay");
-
-  if (stuck_meta >= 0) {
-    if (num == stuck_meta)
-      print(", forced for checking");
-  } else if (txnid > envinfo.mi_recent_txnid &&
-             (envflags & (MDBX_EXCLUSIVE | MDBX_RDONLY)) == MDBX_EXCLUSIVE)
-    print(", rolled-back %" PRIu64 " (%" PRIu64 " >>> %" PRIu64 ")",
-          txnid - envinfo.mi_recent_txnid, txnid, envinfo.mi_recent_txnid);
-  print("\n");
-}
-
-static uint64_t get_meta_txnid(const unsigned meta_id) {
-  switch (meta_id) {
-  default:
-    assert(false);
-    error("unexpected meta_id %u\n", meta_id);
-    return 0;
-  case 0:
-    return envinfo.mi_meta0_txnid;
-  case 1:
-    return envinfo.mi_meta1_txnid;
-  case 2:
-    return envinfo.mi_meta2_txnid;
-  }
-}
-
-static void print_size(const char *prefix, const uint64_t value,
-                       const char *suffix) {
-  const char sf[] =
-      "KMGTPEZY"; /* LY: Kilo, Mega, Giga, Tera, Peta, Exa, Zetta, Yotta! */
-  double k = 1024.0;
-  size_t i;
-  for (i = 0; sf[i + 1] && value / k > 1000.0; ++i)
-    k *= 1024;
-  print("%s%" PRIu64 " (%.2f %cb)%s", prefix, value, value / k, sf[i], suffix);
-}
-
-int main(int argc, char *argv[]) {
-  int rc;
-  char *prog = argv[0];
-  char *envname;
-  int problems_maindb = 0, problems_freedb = 0, problems_meta = 0;
-  bool write_locked = false;
-  bool turn_meta = false;
-  bool force_turn_meta = false;
-
-  double elapsed;
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t timestamp_start, timestamp_finish;
-  timestamp_start = GetMilliseconds();
-#else
-  struct timespec timestamp_start, timestamp_finish;
-  if (clock_gettime(CLOCK_MONOTONIC, &timestamp_start)) {
-    rc = errno;
-    error("clock_gettime failed, error %d %s\n", rc, mdbx_strerror(rc));
-    return EXIT_FAILURE_SYS;
-  }
-#endif
-
-  dbi_meta.name = "@META";
-  dbi_free.name = "@GC";
-  dbi_main.name = "@MAIN";
-  atexit(pagemap_cleanup);
-
-  if (argc < 2)
-    usage(prog);
-
-  for (int i; (i = getopt(argc, argv,
-                          "0"
-                          "1"
-                          "2"
-                          "T"
-                          "V"
-                          "v"
-                          "q"
-                          "n"
-                          "w"
-                          "c"
-                          "t"
-                          "d"
-                          "i"
-                          "s:")) != EOF;) {
-    switch (i) {
-    case 'V':
-      printf("mdbx_chk version %d.%d.%d.%d\n"
-             " - source: %s %s, commit %s, tree %s\n"
-             " - anchor: %s\n"
-             " - build: %s for %s by %s\n"
-             " - flags: %s\n"
-             " - options: %s\n",
-             mdbx_version.major, mdbx_version.minor, mdbx_version.release,
-             mdbx_version.revision, mdbx_version.git.describe,
-             mdbx_version.git.datetime, mdbx_version.git.commit,
-             mdbx_version.git.tree, mdbx_sourcery_anchor, mdbx_build.datetime,
-             mdbx_build.target, mdbx_build.compiler, mdbx_build.flags,
-             mdbx_build.options);
-      return EXIT_SUCCESS;
-    case 'v':
-      verbose++;
-      break;
-    case '0':
-      stuck_meta = 0;
-      break;
-    case '1':
-      stuck_meta = 1;
-      break;
-    case '2':
-      stuck_meta = 2;
-      break;
-    case 't':
-      turn_meta = true;
-      break;
-    case 'T':
-      turn_meta = force_turn_meta = true;
-      quiet = false;
-      if (verbose < 2)
-        verbose = 2;
-      break;
-    case 'q':
-      quiet = true;
-      break;
-    case 'n':
-      envflags |= MDBX_NOSUBDIR;
-      break;
-    case 'w':
-      envflags &= ~MDBX_RDONLY;
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-      /* Temporary `workaround` for OpenBSD kernel's flaw.
-       * See https://github.com/erthink/libmdbx/issues/67 */
-      envflags |= MDBX_WRITEMAP;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-      break;
-    case 'c':
-      envflags = (envflags & ~MDBX_EXCLUSIVE) | MDBX_ACCEDE;
-      break;
-    case 'd':
-      dont_traversal = true;
-      break;
-    case 's':
-      if (only_subdb && strcmp(only_subdb, optarg))
-        usage(prog);
-      only_subdb = optarg;
-      break;
-    case 'i':
-      ignore_wrong_order = true;
-      break;
-    default:
-      usage(prog);
-    }
-  }
-
-  if (optind != argc - 1)
-    usage(prog);
-
-  rc = MDBX_SUCCESS;
-  if (stuck_meta >= 0 && (envflags & MDBX_EXCLUSIVE) == 0) {
-    error("exclusive mode is required to using specific meta-page(%d) for "
-          "checking.\n",
-          stuck_meta);
-    rc = EXIT_INTERRUPTED;
-  }
-  if (turn_meta) {
-    if (stuck_meta < 0) {
-      error("meta-page must be specified (by -0, -1 or -2 options) to turn to "
-            "it.\n");
-      rc = EXIT_INTERRUPTED;
-    }
-    if (envflags & MDBX_RDONLY) {
-      error("write-mode must be enabled to turn to the specified meta-page.\n");
-      rc = EXIT_INTERRUPTED;
-    }
-    if (only_subdb || dont_traversal) {
-      error("whole database checking with tree-traversal are required to turn "
-            "to the specified meta-page.\n");
-      rc = EXIT_INTERRUPTED;
-    }
-  }
-  if (rc)
-    exit(rc);
-
-#if defined(_WIN32) || defined(_WIN64)
-  SetConsoleCtrlHandler(ConsoleBreakHandlerRoutine, true);
-#else
-#ifdef SIGPIPE
-  signal(SIGPIPE, signal_handler);
-#endif
-#ifdef SIGHUP
-  signal(SIGHUP, signal_handler);
-#endif
-  signal(SIGINT, signal_handler);
-  signal(SIGTERM, signal_handler);
-#endif /* !WINDOWS */
-
-  envname = argv[optind];
-  print("mdbx_chk %s (%s, T-%s)\nRunning for %s in 'read-%s' mode...\n",
-        mdbx_version.git.describe, mdbx_version.git.datetime,
-        mdbx_version.git.tree, envname,
-        (envflags & MDBX_RDONLY) ? "only" : "write");
-  fflush(nullptr);
-  mdbx_setup_debug((verbose < MDBX_LOG_TRACE - 1)
-                       ? (MDBX_log_level_t)(verbose + 1)
-                       : MDBX_LOG_TRACE,
-                   MDBX_DBG_LEGACY_OVERLAP, logger);
-
-  rc = mdbx_env_create(&env);
-  if (rc) {
-    error("mdbx_env_create failed, error %d %s\n", rc, mdbx_strerror(rc));
-    return rc < 0 ? EXIT_FAILURE_MDBX : EXIT_FAILURE_SYS;
-  }
-
-  rc = mdbx_env_set_maxdbs(env, MDBX_MAX_DBI);
-  if (rc) {
-    error("mdbx_env_set_maxdbs failed, error %d %s\n", rc, mdbx_strerror(rc));
-    goto bailout;
-  }
-
-  if (stuck_meta >= 0) {
-    rc = mdbx_env_open_for_recovery(env, envname, stuck_meta,
-                                    (envflags & MDBX_RDONLY) ? false : true);
-  } else {
-    rc = mdbx_env_open(env, envname, envflags, 0);
-    if ((envflags & MDBX_EXCLUSIVE) &&
-        (rc == MDBX_BUSY ||
-#if defined(_WIN32) || defined(_WIN64)
-         rc == ERROR_LOCK_VIOLATION || rc == ERROR_SHARING_VIOLATION
-#else
-         rc == EBUSY || rc == EAGAIN
-#endif
-         )) {
-      envflags &= ~MDBX_EXCLUSIVE;
-      rc = mdbx_env_open(env, envname, envflags | MDBX_ACCEDE, 0);
-    }
-  }
-
-  if (rc) {
-    error("mdbx_env_open failed, error %d %s\n", rc, mdbx_strerror(rc));
-    if (rc == MDBX_WANNA_RECOVERY && (envflags & MDBX_RDONLY))
-      print("Please run %s in the read-write mode (with '-w' option).\n", prog);
-    goto bailout;
-  }
-  if (verbose)
-    print(" - %s mode\n",
-          (envflags & MDBX_EXCLUSIVE) ? "monopolistic" : "cooperative");
-
-  if ((envflags & (MDBX_RDONLY | MDBX_EXCLUSIVE)) == 0) {
-    rc = mdbx_txn_lock(env, false);
-    if (rc != MDBX_SUCCESS) {
-      error("mdbx_txn_lock failed, error %d %s\n", rc, mdbx_strerror(rc));
-      goto bailout;
-    }
-    write_locked = true;
-  }
-
-  rc = mdbx_txn_begin(env, nullptr, MDBX_TXN_RDONLY, &txn);
-  if (rc) {
-    error("mdbx_txn_begin() failed, error %d %s\n", rc, mdbx_strerror(rc));
-    goto bailout;
-  }
-
-  rc = mdbx_env_info_ex(env, txn, &envinfo, sizeof(envinfo));
-  if (rc) {
-    error("mdbx_env_info failed, error %d %s\n", rc, mdbx_strerror(rc));
-    goto bailout;
-  }
-  if (verbose) {
-    print(" - current boot-id ");
-    if (envinfo.mi_bootid.current.x | envinfo.mi_bootid.current.y)
-      print("%016" PRIx64 "-%016" PRIx64 "\n", envinfo.mi_bootid.current.x,
-            envinfo.mi_bootid.current.y);
-    else
-      print("unavailable\n");
-  }
-
-  rc = mdbx_env_stat_ex(env, txn, &envstat, sizeof(envstat));
-  if (rc) {
-    error("mdbx_env_stat failed, error %d %s\n", rc, mdbx_strerror(rc));
-    goto bailout;
-  }
-
-  mdbx_filehandle_t dxb_fd;
-  rc = mdbx_env_get_fd(env, &dxb_fd);
-  if (rc) {
-    error("mdbx_env_get_fd failed, error %d %s\n", rc, mdbx_strerror(rc));
-    goto bailout;
-  }
-
-  uint64_t dxb_filesize = 0;
-#if defined(_WIN32) || defined(_WIN64)
-  {
-    BY_HANDLE_FILE_INFORMATION info;
-    if (!GetFileInformationByHandle(dxb_fd, &info))
-      rc = GetLastError();
-    else
-      dxb_filesize = info.nFileSizeLow | (uint64_t)info.nFileSizeHigh << 32;
-  }
-#else
-  {
-    struct stat st;
-    STATIC_ASSERT_MSG(sizeof(off_t) <= sizeof(uint64_t),
-                      "libmdbx requires 64-bit file I/O on 64-bit systems");
-    if (fstat(dxb_fd, &st))
-      rc = errno;
-    else
-      dxb_filesize = st.st_size;
-  }
-#endif
-  if (rc) {
-    error("mdbx_filesize failed, error %d %s\n", rc, mdbx_strerror(rc));
-    goto bailout;
-  }
-
-  errno = 0;
-  const uint64_t dxbfile_pages = dxb_filesize / envinfo.mi_dxb_pagesize;
-  alloc_pages = txn->mt_next_pgno;
-  backed_pages = envinfo.mi_geo.current / envinfo.mi_dxb_pagesize;
-  if (backed_pages > dxbfile_pages) {
-    print(" ! backed-pages %" PRIu64 " > file-pages %" PRIu64 "\n",
-          backed_pages, dxbfile_pages);
-    ++problems_meta;
-  }
-  if (dxbfile_pages < NUM_METAS)
-    print(" ! file-pages %" PRIu64 " < %u\n", dxbfile_pages, NUM_METAS);
-  if (backed_pages < NUM_METAS)
-    print(" ! backed-pages %" PRIu64 " < %u\n", backed_pages, NUM_METAS);
-  if (backed_pages < NUM_METAS || dxbfile_pages < NUM_METAS)
-    goto bailout;
-  if (backed_pages > MAX_PAGENO) {
-    print(" ! backed-pages %" PRIu64 " > max-pages %" PRIaPGNO "\n",
-          backed_pages, MAX_PAGENO);
-    ++problems_meta;
-    backed_pages = MAX_PAGENO;
-  }
-
-  if ((envflags & (MDBX_EXCLUSIVE | MDBX_RDONLY)) != MDBX_RDONLY) {
-    if (backed_pages > dxbfile_pages) {
-      print(" ! backed-pages %" PRIu64 " > file-pages %" PRIu64 "\n",
-            backed_pages, dxbfile_pages);
-      ++problems_meta;
-      backed_pages = dxbfile_pages;
-    }
-    if (alloc_pages > backed_pages) {
-      print(" ! alloc-pages %" PRIu64 " > backed-pages %" PRIu64 "\n",
-            alloc_pages, backed_pages);
-      ++problems_meta;
-      alloc_pages = backed_pages;
-    }
-  } else {
-    /* LY: DB may be shrinked by writer down to the allocated pages. */
-    if (alloc_pages > backed_pages) {
-      print(" ! alloc-pages %" PRIu64 " > backed-pages %" PRIu64 "\n",
-            alloc_pages, backed_pages);
-      ++problems_meta;
-      alloc_pages = backed_pages;
-    }
-    if (alloc_pages > dxbfile_pages) {
-      print(" ! alloc-pages %" PRIu64 " > file-pages %" PRIu64 "\n",
-            alloc_pages, dxbfile_pages);
-      ++problems_meta;
-      alloc_pages = dxbfile_pages;
-    }
-    if (backed_pages > dxbfile_pages)
-      backed_pages = dxbfile_pages;
-  }
-
-  if (verbose) {
-    print(" - pagesize %u (%u system), max keysize %d..%d"
-          ", max readers %u\n",
-          envinfo.mi_dxb_pagesize, envinfo.mi_sys_pagesize,
-          mdbx_env_get_maxkeysize_ex(env, MDBX_DUPSORT),
-          mdbx_env_get_maxkeysize_ex(env, 0), envinfo.mi_maxreaders);
-    print_size(" - mapsize ", envinfo.mi_mapsize, "\n");
-    if (envinfo.mi_geo.lower == envinfo.mi_geo.upper)
-      print_size(" - fixed datafile: ", envinfo.mi_geo.current, "");
-    else {
-      print_size(" - dynamic datafile: ", envinfo.mi_geo.lower, "");
-      print_size(" .. ", envinfo.mi_geo.upper, ", ");
-      print_size("+", envinfo.mi_geo.grow, ", ");
-      print_size("-", envinfo.mi_geo.shrink, "\n");
-      print_size(" - current datafile: ", envinfo.mi_geo.current, "");
-    }
-    printf(", %" PRIu64 " pages\n",
-           envinfo.mi_geo.current / envinfo.mi_dxb_pagesize);
-#if defined(_WIN32) || defined(_WIN64)
-    if (envinfo.mi_geo.shrink && envinfo.mi_geo.current != envinfo.mi_geo.upper)
-      print(
-          "                     WARNING: Due Windows system limitations a "
-          "file couldn't\n                     be truncated while the database "
-          "is opened. So, the size\n                     database file "
-          "of may by large than the database itself,\n                     "
-          "until it will be closed or reopened in read-write mode.\n");
-#endif
-    print(" - transactions: recent %" PRIu64 ", latter reader %" PRIu64
-          ", lag %" PRIi64 "\n",
-          envinfo.mi_recent_txnid, envinfo.mi_latter_reader_txnid,
-          envinfo.mi_recent_txnid - envinfo.mi_latter_reader_txnid);
-
-    verbose_meta(0, envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign,
-                 envinfo.mi_bootid.meta0.x, envinfo.mi_bootid.meta0.y);
-    verbose_meta(1, envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign,
-                 envinfo.mi_bootid.meta1.x, envinfo.mi_bootid.meta1.y);
-    verbose_meta(2, envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign,
-                 envinfo.mi_bootid.meta2.x, envinfo.mi_bootid.meta2.y);
-  }
-
-  if (verbose > 1)
-    print(" - performs check for meta-pages clashes\n");
-  if (meta_eq(envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign,
-              envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign)) {
-    print(" ! meta-%d and meta-%d are clashed\n", 0, 1);
-    ++problems_meta;
-  }
-  if (meta_eq(envinfo.mi_meta1_txnid, envinfo.mi_meta1_sign,
-              envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign)) {
-    print(" ! meta-%d and meta-%d are clashed\n", 1, 2);
-    ++problems_meta;
-  }
-  if (meta_eq(envinfo.mi_meta2_txnid, envinfo.mi_meta2_sign,
-              envinfo.mi_meta0_txnid, envinfo.mi_meta0_sign)) {
-    print(" ! meta-%d and meta-%d are clashed\n", 2, 0);
-    ++problems_meta;
-  }
-
-  const unsigned steady_meta_id = meta_recent(true);
-  const uint64_t steady_meta_txnid = get_meta_txnid(steady_meta_id);
-  const unsigned weak_meta_id = meta_recent(false);
-  const uint64_t weak_meta_txnid = get_meta_txnid(weak_meta_id);
-  if (envflags & MDBX_EXCLUSIVE) {
-    if (verbose > 1)
-      print(" - performs full check recent-txn-id with meta-pages\n");
-    if (steady_meta_txnid != envinfo.mi_recent_txnid) {
-      print(" ! steady meta-%d txn-id mismatch recent-txn-id (%" PRIi64
-            " != %" PRIi64 ")\n",
-            steady_meta_id, steady_meta_txnid, envinfo.mi_recent_txnid);
-      ++problems_meta;
-    }
-  } else if (write_locked) {
-    if (verbose > 1)
-      print(" - performs lite check recent-txn-id with meta-pages (not a "
-            "monopolistic mode)\n");
-    if (weak_meta_txnid != envinfo.mi_recent_txnid) {
-      print(" ! weak meta-%d txn-id mismatch recent-txn-id (%" PRIi64
-            " != %" PRIi64 ")\n",
-            weak_meta_id, weak_meta_txnid, envinfo.mi_recent_txnid);
-      ++problems_meta;
-    }
-  } else if (verbose) {
-    print(" - skip check recent-txn-id with meta-pages (monopolistic or "
-          "read-write mode only)\n");
-  }
-  total_problems += problems_meta;
-
-  if (!dont_traversal) {
-    struct problem *saved_list;
-    size_t traversal_problems;
-    uint64_t empty_pages, lost_bytes;
-
-    print("Traversal b-tree by txn#%" PRIaTXN "...\n", txn->mt_txnid);
-    fflush(nullptr);
-    walk.pagemap = mdbx_calloc((size_t)backed_pages, sizeof(*walk.pagemap));
-    if (!walk.pagemap) {
-      rc = errno ? errno : MDBX_ENOMEM;
-      error("calloc failed, error %d %s\n", rc, mdbx_strerror(rc));
-      goto bailout;
-    }
-
-    saved_list = problems_push();
-    rc = mdbx_env_pgwalk(txn, pgvisitor, nullptr,
-                         true /* always skip key ordering checking to avoid
-                               MDBX_CORRUPTED when using custom comparators */);
-    traversal_problems = problems_pop(saved_list);
-
-    if (rc) {
-      if (rc != MDBX_EINTR || !check_user_break())
-        error("mdbx_env_pgwalk failed, error %d %s\n", rc, mdbx_strerror(rc));
-      goto bailout;
-    }
-
-    for (uint64_t n = 0; n < alloc_pages; ++n)
-      if (!walk.pagemap[n])
-        unused_pages += 1;
-
-    empty_pages = lost_bytes = 0;
-    for (walk_dbi_t *dbi = &dbi_main; dbi < ARRAY_END(walk.dbi) && dbi->name;
-         ++dbi) {
-      empty_pages += dbi->pages.empty;
-      lost_bytes += dbi->lost_bytes;
-    }
-
-    if (verbose) {
-      uint64_t total_page_bytes = walk.pgcount * envstat.ms_psize;
-      print(" - pages: walked %" PRIu64 ", left/unused %" PRIu64 "\n",
-            walk.pgcount, unused_pages);
-      if (verbose > 1) {
-        for (walk_dbi_t *dbi = walk.dbi; dbi < ARRAY_END(walk.dbi) && dbi->name;
-             ++dbi) {
-          print("     %s: subtotal %" PRIu64, dbi->name, dbi->pages.total);
-          if (dbi->pages.other && dbi->pages.other != dbi->pages.total)
-            print(", other %" PRIu64, dbi->pages.other);
-          if (dbi->pages.branch)
-            print(", branch %" PRIu64, dbi->pages.branch);
-          if (dbi->pages.large_count)
-            print(", large %" PRIu64, dbi->pages.large_count);
-          uint64_t all_leaf = dbi->pages.leaf + dbi->pages.leaf_dupfixed;
-          if (all_leaf) {
-            print(", leaf %" PRIu64, all_leaf);
-            if (verbose > 2 &&
-                (dbi->pages.leaf_dupfixed | dbi->pages.subleaf_dupsort |
-                 dbi->pages.subleaf_dupsort))
-              print(" (usual %" PRIu64 ", sub-dupsort %" PRIu64
-                    ", dupfixed %" PRIu64 ", sub-dupfixed %" PRIu64 ")",
-                    dbi->pages.leaf, dbi->pages.subleaf_dupsort,
-                    dbi->pages.leaf_dupfixed, dbi->pages.subleaf_dupfixed);
-          }
-          print("\n");
-        }
-      }
-
-      if (verbose > 1)
-        print(" - usage: total %" PRIu64 " bytes, payload %" PRIu64
-              " (%.1f%%), unused "
-              "%" PRIu64 " (%.1f%%)\n",
-              total_page_bytes, walk.total_payload_bytes,
-              walk.total_payload_bytes * 100.0 / total_page_bytes,
-              total_page_bytes - walk.total_payload_bytes,
-              (total_page_bytes - walk.total_payload_bytes) * 100.0 /
-                  total_page_bytes);
-      if (verbose > 2) {
-        for (walk_dbi_t *dbi = walk.dbi; dbi < ARRAY_END(walk.dbi) && dbi->name;
-             ++dbi)
-          if (dbi->pages.total) {
-            uint64_t dbi_bytes = dbi->pages.total * envstat.ms_psize;
-            print("     %s: subtotal %" PRIu64 " bytes (%.1f%%),"
-                  " payload %" PRIu64 " (%.1f%%), unused %" PRIu64 " (%.1f%%)",
-                  dbi->name, dbi_bytes, dbi_bytes * 100.0 / total_page_bytes,
-                  dbi->payload_bytes, dbi->payload_bytes * 100.0 / dbi_bytes,
-                  dbi_bytes - dbi->payload_bytes,
-                  (dbi_bytes - dbi->payload_bytes) * 100.0 / dbi_bytes);
-            if (dbi->pages.empty)
-              print(", %" PRIu64 " empty pages", dbi->pages.empty);
-            if (dbi->lost_bytes)
-              print(", %" PRIu64 " bytes lost", dbi->lost_bytes);
-            print("\n");
-          } else
-            print("     %s: empty\n", dbi->name);
-      }
-      print(" - summary: average fill %.1f%%",
-            walk.total_payload_bytes * 100.0 / total_page_bytes);
-      if (empty_pages)
-        print(", %" PRIu64 " empty pages", empty_pages);
-      if (lost_bytes)
-        print(", %" PRIu64 " bytes lost", lost_bytes);
-      print(", %" PRIuPTR " problems\n", traversal_problems);
-    }
-  } else if (verbose) {
-    print("Skipping b-tree walk...\n");
-    fflush(nullptr);
-  }
-
-  if (!verbose)
-    print("Iterating DBIs...\n");
-  problems_maindb = process_db(~0u, /* MAIN_DBI */ nullptr, nullptr, false);
-  problems_freedb = process_db(FREE_DBI, "@GC", handle_freedb, false);
-
-  if (verbose) {
-    uint64_t value = envinfo.mi_mapsize / envstat.ms_psize;
-    double percent = value / 100.0;
-    print(" - space: %" PRIu64 " total pages", value);
-    print(", backed %" PRIu64 " (%.1f%%)", backed_pages,
-          backed_pages / percent);
-    print(", allocated %" PRIu64 " (%.1f%%)", alloc_pages,
-          alloc_pages / percent);
-
-    if (verbose > 1) {
-      value = envinfo.mi_mapsize / envstat.ms_psize - alloc_pages;
-      print(", remained %" PRIu64 " (%.1f%%)", value, value / percent);
-
-      value = dont_traversal ? alloc_pages - gc_pages : walk.pgcount;
-      print(", used %" PRIu64 " (%.1f%%)", value, value / percent);
-
-      print(", gc %" PRIu64 " (%.1f%%)", gc_pages, gc_pages / percent);
-
-      value = gc_pages - reclaimable_pages;
-      print(", detained %" PRIu64 " (%.1f%%)", value, value / percent);
-
-      print(", reclaimable %" PRIu64 " (%.1f%%)", reclaimable_pages,
-            reclaimable_pages / percent);
-    }
-
-    value =
-        envinfo.mi_mapsize / envstat.ms_psize - alloc_pages + reclaimable_pages;
-    print(", available %" PRIu64 " (%.1f%%)\n", value, value / percent);
-  }
-
-  if (problems_maindb == 0 && problems_freedb == 0) {
-    if (!dont_traversal &&
-        (envflags & (MDBX_EXCLUSIVE | MDBX_RDONLY)) != MDBX_RDONLY) {
-      if (walk.pgcount != alloc_pages - gc_pages) {
-        error("used pages mismatch (%" PRIu64 "(walked) != %" PRIu64
-              "(allocated - GC))\n",
-              walk.pgcount, alloc_pages - gc_pages);
-      }
-      if (unused_pages != gc_pages) {
-        error("gc pages mismatch (%" PRIu64 "(expected) != %" PRIu64 "(GC))\n",
-              unused_pages, gc_pages);
-      }
-    } else if (verbose) {
-      print(" - skip check used and gc pages (btree-traversal with "
-            "monopolistic or read-write mode only)\n");
-    }
-
-    if (!process_db(MAIN_DBI, nullptr, handle_maindb, true)) {
-      if (!userdb_count && verbose)
-        print(" - does not contain multiple databases\n");
-    }
-  }
-
-  if (rc == 0 && total_problems == 1 && problems_meta == 1 && !dont_traversal &&
-      (envflags & MDBX_RDONLY) == 0 && !only_subdb && stuck_meta < 0 &&
-      steady_meta_txnid < envinfo.mi_recent_txnid) {
-    print("Perform sync-to-disk for make steady checkpoint at txn-id #%" PRIi64
-          "\n",
-          envinfo.mi_recent_txnid);
-    fflush(nullptr);
-    if (write_locked) {
-      mdbx_txn_unlock(env);
-      write_locked = false;
-    }
-    rc = mdbx_env_sync_ex(env, true, false);
-    if (rc != MDBX_SUCCESS)
-      error("mdbx_env_pgwalk failed, error %d %s\n", rc, mdbx_strerror(rc));
-    else {
-      total_problems -= 1;
-      problems_meta -= 1;
-    }
-  }
-
-  if (turn_meta && stuck_meta >= 0 && !dont_traversal && !only_subdb &&
-      (envflags & (MDBX_RDONLY | MDBX_EXCLUSIVE)) == MDBX_EXCLUSIVE) {
-    const bool successful_check = (rc | total_problems | problems_meta) == 0;
-    if (successful_check || force_turn_meta) {
-      fflush(nullptr);
-      print(" = Performing turn to the specified meta-page (%d) due to %s!\n",
-            stuck_meta,
-            successful_check ? "successful check" : "the -T option was given");
-      fflush(nullptr);
-      rc = mdbx_env_turn_for_recovery(env, stuck_meta);
-      if (rc != MDBX_SUCCESS)
-        error("mdbx_env_turn_for_recovery failed, error %d %s\n", rc,
-              mdbx_strerror(rc));
-    } else {
-      print(" = Skipping turn to the specified meta-page (%d) due to "
-            "unsuccessful check!\n",
-            stuck_meta);
-    }
-  }
-
-bailout:
-  if (txn)
-    mdbx_txn_abort(txn);
-  if (write_locked) {
-    mdbx_txn_unlock(env);
-    write_locked = false;
-  }
-  if (env) {
-    const bool dont_sync = rc != 0 || total_problems;
-    mdbx_env_close_ex(env, dont_sync);
-  }
-  fflush(nullptr);
-  if (rc) {
-    if (rc < 0)
-      return user_break ? EXIT_INTERRUPTED : EXIT_FAILURE_SYS;
-    return EXIT_FAILURE_MDBX;
-  }
-
-#if defined(_WIN32) || defined(_WIN64)
-  timestamp_finish = GetMilliseconds();
-  elapsed = (timestamp_finish - timestamp_start) * 1e-3;
-#else
-  if (clock_gettime(CLOCK_MONOTONIC, &timestamp_finish)) {
-    rc = errno;
-    error("clock_gettime failed, error %d %s\n", rc, mdbx_strerror(rc));
-    return EXIT_FAILURE_SYS;
-  }
-  elapsed = timestamp_finish.tv_sec - timestamp_start.tv_sec +
-            (timestamp_finish.tv_nsec - timestamp_start.tv_nsec) * 1e-9;
-#endif /* !WINDOWS */
-
-  if (total_problems) {
-    print("Total %" PRIu64 " error%s detected, elapsed %.3f seconds.\n",
-          total_problems, (total_problems > 1) ? "s are" : " is", elapsed);
-    if (problems_meta || problems_maindb || problems_freedb)
-      return EXIT_FAILURE_CHECK_MAJOR;
-    return EXIT_FAILURE_CHECK_MINOR;
-  }
-  print("No error is detected, elapsed %.3f seconds\n", elapsed);
-  return EXIT_SUCCESS;
-}
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx_copy.c b/plugins/Dbx_mdbx/src/libmdbx/mdbx_copy.c
deleted file mode 100644
index faec17ac15..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx_copy.c
+++ /dev/null
@@ -1,3270 +0,0 @@
-/* mdbx_copy.c - memory-mapped database backup tool */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#ifdef _MSC_VER
-#if _MSC_VER > 1800
-#pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#pragma warning(disable : 4996) /* The POSIX name is deprecated... */
-#endif                          /* _MSC_VER (warnings) */
-
-#define MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-
-#if defined(_WIN32) || defined(_WIN64)
-/*
- * POSIX getopt for Windows
- *
- * AT&T Public License
- *
- * Code given out at the 1985 UNIFORUM conference in Dallas.
- */
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#endif /* _MSC_VER (warnings) */
-
-#include <stdio.h>
-#include <string.h>
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-/*----------------------------------------------------------------------------*/
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-#ifndef EOF
-#define EOF (-1)
-#endif
-
-int optind = 1;
-int optopt;
-char *optarg;
-
-int getopt(int argc, char *const argv[], const char *opts) {
-  static int sp = 1;
-  int c;
-  const char *cp;
-
-  if (sp == 1) {
-    if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0')
-      return EOF;
-    else if (strcmp(argv[optind], "--") == 0) {
-      optind++;
-      return EOF;
-    }
-  }
-  optopt = c = argv[optind][sp];
-  if (c == ':' || (cp = strchr(opts, c)) == NULL) {
-    fprintf(stderr, "%s: %s -- %c\n", argv[0], "illegal option", c);
-    if (argv[optind][++sp] == '\0') {
-      optind++;
-      sp = 1;
-    }
-    return '?';
-  }
-  if (*++cp == ':') {
-    if (argv[optind][sp + 1] != '\0')
-      optarg = &argv[optind++][sp + 1];
-    else if (++optind >= argc) {
-      fprintf(stderr, "%s: %s -- %c\n", argv[0], "option requires an argument",
-              c);
-      sp = 1;
-      return '?';
-    } else
-      optarg = argv[optind++];
-    sp = 1;
-  } else {
-    if (argv[optind][++sp] == '\0') {
-      sp = 1;
-      optind++;
-    }
-    optarg = NULL;
-  }
-  return c;
-}
-
-static volatile BOOL user_break;
-static BOOL WINAPI ConsoleBreakHandlerRoutine(DWORD dwCtrlType) {
-  (void)dwCtrlType;
-  user_break = true;
-  return true;
-}
-
-#else /* WINDOWS */
-
-static volatile sig_atomic_t user_break;
-static void signal_handler(int sig) {
-  (void)sig;
-  user_break = 1;
-}
-
-#endif /* !WINDOWS */
-
-static void usage(const char *prog) {
-  fprintf(stderr,
-          "usage: %s [-V] [-q] [-c] src_path [dest_path]\n"
-          "  -V\t\tprint version and exit\n"
-          "  -q\t\tbe quiet\n"
-          "  -c\t\tenable compactification (skip unused pages)\n"
-          "  src_path\tsource database\n"
-          "  dest_path\tdestination (stdout if not specified)\n",
-          prog);
-  exit(EXIT_FAILURE);
-}
-
-int main(int argc, char *argv[]) {
-  int rc;
-  MDBX_env *env = NULL;
-  const char *progname = argv[0], *act;
-  unsigned flags = MDBX_RDONLY;
-  unsigned cpflags = 0;
-  bool quiet = false;
-
-  for (; argc > 1 && argv[1][0] == '-'; argc--, argv++) {
-    if (argv[1][1] == 'n' && argv[1][2] == '\0')
-      flags |= MDBX_NOSUBDIR;
-    else if (argv[1][1] == 'c' && argv[1][2] == '\0')
-      cpflags |= MDBX_CP_COMPACT;
-    else if (argv[1][1] == 'q' && argv[1][2] == '\0')
-      quiet = true;
-    else if ((argv[1][1] == 'h' && argv[1][2] == '\0') ||
-             strcmp(argv[1], "--help") == 0)
-      usage(progname);
-    else if (argv[1][1] == 'V' && argv[1][2] == '\0') {
-      printf("mdbx_copy version %d.%d.%d.%d\n"
-             " - source: %s %s, commit %s, tree %s\n"
-             " - anchor: %s\n"
-             " - build: %s for %s by %s\n"
-             " - flags: %s\n"
-             " - options: %s\n",
-             mdbx_version.major, mdbx_version.minor, mdbx_version.release,
-             mdbx_version.revision, mdbx_version.git.describe,
-             mdbx_version.git.datetime, mdbx_version.git.commit,
-             mdbx_version.git.tree, mdbx_sourcery_anchor, mdbx_build.datetime,
-             mdbx_build.target, mdbx_build.compiler, mdbx_build.flags,
-             mdbx_build.options);
-      return EXIT_SUCCESS;
-    } else
-      argc = 0;
-  }
-
-  if (argc < 2 || argc > 3)
-    usage(progname);
-
-#if defined(_WIN32) || defined(_WIN64)
-  SetConsoleCtrlHandler(ConsoleBreakHandlerRoutine, true);
-#else
-#ifdef SIGPIPE
-  signal(SIGPIPE, signal_handler);
-#endif
-#ifdef SIGHUP
-  signal(SIGHUP, signal_handler);
-#endif
-  signal(SIGINT, signal_handler);
-  signal(SIGTERM, signal_handler);
-#endif /* !WINDOWS */
-
-  if (!quiet) {
-    fprintf((argc == 2) ? stderr : stdout,
-            "mdbx_copy %s (%s, T-%s)\nRunning for copy %s to %s...\n",
-            mdbx_version.git.describe, mdbx_version.git.datetime,
-            mdbx_version.git.tree, argv[1], (argc == 2) ? "stdout" : argv[2]);
-    fflush(NULL);
-  }
-
-  act = "opening environment";
-  rc = mdbx_env_create(&env);
-  if (rc == MDBX_SUCCESS) {
-    rc = mdbx_env_open(env, argv[1], flags, 0640);
-  }
-  if (rc == MDBX_SUCCESS) {
-    act = "copying";
-    if (argc == 2) {
-      mdbx_filehandle_t fd;
-#if defined(_WIN32) || defined(_WIN64)
-      fd = GetStdHandle(STD_OUTPUT_HANDLE);
-#else
-      fd = fileno(stdout);
-#endif
-      rc = mdbx_env_copy2fd(env, fd, cpflags);
-    } else
-      rc = mdbx_env_copy(env, argv[2], cpflags);
-  }
-  if (rc)
-    fprintf(stderr, "%s: %s failed, error %d (%s)\n", progname, act, rc,
-            mdbx_strerror(rc));
-  mdbx_env_close(env);
-
-  return rc ? EXIT_FAILURE : EXIT_SUCCESS;
-}
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx_dump.c b/plugins/Dbx_mdbx/src/libmdbx/mdbx_dump.c
deleted file mode 100644
index abf82b0d7c..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx_dump.c
+++ /dev/null
@@ -1,3626 +0,0 @@
-/* mdbx_dump.c - memory-mapped database dump tool */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#ifdef _MSC_VER
-#if _MSC_VER > 1800
-#pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#pragma warning(disable : 4996) /* The POSIX name is deprecated... */
-#endif                          /* _MSC_VER (warnings) */
-
-#define MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-
-#include <ctype.h>
-
-#define PRINT 1
-#define GLOBAL 2
-static int mode = GLOBAL;
-
-typedef struct flagbit {
-  int bit;
-  char *name;
-} flagbit;
-
-flagbit dbflags[] = {{MDBX_REVERSEKEY, "reversekey"},
-                     {MDBX_DUPSORT, "dupsort"},
-                     {MDBX_INTEGERKEY, "integerkey"},
-                     {MDBX_DUPFIXED, "dupfixed"},
-                     {MDBX_INTEGERDUP, "integerdup"},
-                     {MDBX_REVERSEDUP, "reversedup"},
-                     {0, nullptr}};
-
-#if defined(_WIN32) || defined(_WIN64)
-/*
- * POSIX getopt for Windows
- *
- * AT&T Public License
- *
- * Code given out at the 1985 UNIFORUM conference in Dallas.
- */
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#endif /* _MSC_VER (warnings) */
-
-#include <stdio.h>
-#include <string.h>
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-/*----------------------------------------------------------------------------*/
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-#ifndef EOF
-#define EOF (-1)
-#endif
-
-int optind = 1;
-int optopt;
-char *optarg;
-
-int getopt(int argc, char *const argv[], const char *opts) {
-  static int sp = 1;
-  int c;
-  const char *cp;
-
-  if (sp == 1) {
-    if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0')
-      return EOF;
-    else if (strcmp(argv[optind], "--") == 0) {
-      optind++;
-      return EOF;
-    }
-  }
-  optopt = c = argv[optind][sp];
-  if (c == ':' || (cp = strchr(opts, c)) == NULL) {
-    fprintf(stderr, "%s: %s -- %c\n", argv[0], "illegal option", c);
-    if (argv[optind][++sp] == '\0') {
-      optind++;
-      sp = 1;
-    }
-    return '?';
-  }
-  if (*++cp == ':') {
-    if (argv[optind][sp + 1] != '\0')
-      optarg = &argv[optind++][sp + 1];
-    else if (++optind >= argc) {
-      fprintf(stderr, "%s: %s -- %c\n", argv[0], "option requires an argument",
-              c);
-      sp = 1;
-      return '?';
-    } else
-      optarg = argv[optind++];
-    sp = 1;
-  } else {
-    if (argv[optind][++sp] == '\0') {
-      sp = 1;
-      optind++;
-    }
-    optarg = NULL;
-  }
-  return c;
-}
-
-static volatile BOOL user_break;
-static BOOL WINAPI ConsoleBreakHandlerRoutine(DWORD dwCtrlType) {
-  (void)dwCtrlType;
-  user_break = true;
-  return true;
-}
-
-#else /* WINDOWS */
-
-static volatile sig_atomic_t user_break;
-static void signal_handler(int sig) {
-  (void)sig;
-  user_break = 1;
-}
-
-#endif /* !WINDOWS */
-
-static const char hexc[] = "0123456789abcdef";
-
-static void dumpbyte(unsigned char c) {
-  putchar(hexc[c >> 4]);
-  putchar(hexc[c & 0xf]);
-}
-
-static void text(MDBX_val *v) {
-  unsigned char *c, *end;
-
-  putchar(' ');
-  c = v->iov_base;
-  end = c + v->iov_len;
-  while (c < end) {
-    if (isprint(*c) && *c != '\\') {
-      putchar(*c);
-    } else {
-      putchar('\\');
-      dumpbyte(*c);
-    }
-    c++;
-  }
-  putchar('\n');
-}
-
-static void dumpval(MDBX_val *v) {
-  unsigned char *c, *end;
-
-  putchar(' ');
-  c = v->iov_base;
-  end = c + v->iov_len;
-  while (c < end)
-    dumpbyte(*c++);
-  putchar('\n');
-}
-
-bool quiet = false, rescue = false;
-const char *prog;
-static void error(const char *func, int rc) {
-  fprintf(stderr, "%s: %s() error %d %s\n", prog, func, rc, mdbx_strerror(rc));
-}
-
-/* Dump in BDB-compatible format */
-static int dump_sdb(MDBX_txn *txn, MDBX_dbi dbi, char *name) {
-  unsigned int flags;
-  int rc = mdbx_dbi_flags(txn, dbi, &flags);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_dbi_flags", rc);
-    return rc;
-  }
-
-  MDBX_stat ms;
-  rc = mdbx_dbi_stat(txn, dbi, &ms, sizeof(ms));
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_dbi_stat", rc);
-    return rc;
-  }
-
-  MDBX_envinfo info;
-  rc = mdbx_env_info_ex(mdbx_txn_env(txn), txn, &info, sizeof(info));
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_info_ex", rc);
-    return rc;
-  }
-
-  printf("VERSION=3\n");
-  if (mode & GLOBAL) {
-    mode -= GLOBAL;
-    if (info.mi_geo.upper != info.mi_geo.lower)
-      printf("geometry=l%" PRIu64 ",c%" PRIu64 ",u%" PRIu64 ",s%" PRIu64
-             ",g%" PRIu64 "\n",
-             info.mi_geo.lower, info.mi_geo.current, info.mi_geo.upper,
-             info.mi_geo.shrink, info.mi_geo.grow);
-    printf("mapsize=%" PRIu64 "\n", info.mi_geo.upper);
-    printf("maxreaders=%u\n", info.mi_maxreaders);
-
-    MDBX_canary canary;
-    rc = mdbx_canary_get(txn, &canary);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_canary_get", rc);
-      return rc;
-    }
-    if (canary.v)
-      printf("canary=v%" PRIu64 ",x%" PRIu64 ",y%" PRIu64 ",z%" PRIu64 "\n",
-             canary.v, canary.x, canary.y, canary.z);
-  }
-  printf("format=%s\n", mode & PRINT ? "print" : "bytevalue");
-  if (name)
-    printf("database=%s\n", name);
-  printf("type=btree\n");
-  printf("db_pagesize=%u\n", ms.ms_psize);
-  /* if (ms.ms_mod_txnid)
-    printf("txnid=%" PRIaTXN "\n", ms.ms_mod_txnid);
-  else if (!name)
-    printf("txnid=%" PRIaTXN "\n", mdbx_txn_id(txn)); */
-
-  printf("duplicates=%d\n", (flags & (MDBX_DUPSORT | MDBX_DUPFIXED |
-                                      MDBX_INTEGERDUP | MDBX_REVERSEDUP))
-                                ? 1
-                                : 0);
-  for (int i = 0; dbflags[i].bit; i++)
-    if (flags & dbflags[i].bit)
-      printf("%s=1\n", dbflags[i].name);
-
-  uint64_t sequence;
-  rc = mdbx_dbi_sequence(txn, dbi, &sequence, 0);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_dbi_sequence", rc);
-    return rc;
-  }
-  if (sequence)
-    printf("sequence=%" PRIu64 "\n", sequence);
-
-  printf("HEADER=END\n"); /*-------------------------------------------------*/
-
-  MDBX_cursor *cursor;
-  MDBX_val key, data;
-  rc = mdbx_cursor_open(txn, dbi, &cursor);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_cursor_open", rc);
-    return rc;
-  }
-  if (MDBX_DEBUG > 0 && rescue) {
-    cursor->mc_flags |= C_SKIPORD;
-    if (cursor->mc_xcursor)
-      cursor->mc_xcursor->mx_cursor.mc_flags |= C_SKIPORD;
-  }
-
-  while ((rc = mdbx_cursor_get(cursor, &key, &data, MDBX_NEXT)) ==
-         MDBX_SUCCESS) {
-    if (user_break) {
-      rc = MDBX_EINTR;
-      break;
-    }
-    if (mode & PRINT) {
-      text(&key);
-      text(&data);
-    } else {
-      dumpval(&key);
-      dumpval(&data);
-    }
-  }
-  printf("DATA=END\n");
-  if (rc == MDBX_NOTFOUND)
-    rc = MDBX_SUCCESS;
-  if (unlikely(rc != MDBX_SUCCESS))
-    error("mdbx_cursor_get", rc);
-
-  mdbx_cursor_close(cursor);
-  return rc;
-}
-
-static void usage(void) {
-  fprintf(stderr,
-          "usage: %s [-V] [-q] [-f file] [-l] [-p] [-a|-s subdb] [-r] "
-          "dbpath\n"
-          "  -V\t\tprint version and exit\n"
-          "  -q\t\tbe quiet\n"
-          "  -f\t\twrite to file instead of stdout\n"
-          "  -l\t\tlist subDBs and exit\n"
-          "  -p\t\tuse printable characters\n"
-          "  -a\t\tdump main DB and all subDBs,\n"
-          "    \t\tby default dump only the main DB\n"
-          "  -s\t\tdump only the named subDB\n"
-          "  -r\t\trescue mode (ignore errors to dump corrupted DB)\n",
-          prog);
-  exit(EXIT_FAILURE);
-}
-
-static int equal_or_greater(const MDBX_val *a, const MDBX_val *b) {
-  return (a->iov_len == b->iov_len &&
-          memcmp(a->iov_base, b->iov_base, a->iov_len) == 0)
-             ? 0
-             : 1;
-}
-
-int main(int argc, char *argv[]) {
-  int i, rc;
-  MDBX_env *env;
-  MDBX_txn *txn;
-  MDBX_dbi dbi;
-  prog = argv[0];
-  char *envname;
-  char *subname = nullptr, *buf4free = nullptr;
-  unsigned envflags = 0;
-  bool alldbs = false, list = false;
-
-  if (argc < 2)
-    usage();
-
-  while ((i = getopt(argc, argv,
-                     "a"
-                     "f:"
-                     "l"
-                     "n"
-                     "p"
-                     "s:"
-                     "V"
-                     "r"
-                     "q")) != EOF) {
-    switch (i) {
-    case 'V':
-      printf("mdbx_dump version %d.%d.%d.%d\n"
-             " - source: %s %s, commit %s, tree %s\n"
-             " - anchor: %s\n"
-             " - build: %s for %s by %s\n"
-             " - flags: %s\n"
-             " - options: %s\n",
-             mdbx_version.major, mdbx_version.minor, mdbx_version.release,
-             mdbx_version.revision, mdbx_version.git.describe,
-             mdbx_version.git.datetime, mdbx_version.git.commit,
-             mdbx_version.git.tree, mdbx_sourcery_anchor, mdbx_build.datetime,
-             mdbx_build.target, mdbx_build.compiler, mdbx_build.flags,
-             mdbx_build.options);
-      return EXIT_SUCCESS;
-    case 'l':
-      list = true;
-      /*FALLTHROUGH*/;
-      __fallthrough;
-    case 'a':
-      if (subname)
-        usage();
-      alldbs = true;
-      break;
-    case 'f':
-      if (freopen(optarg, "w", stdout) == nullptr) {
-        fprintf(stderr, "%s: %s: reopen: %s\n", prog, optarg,
-                mdbx_strerror(errno));
-        exit(EXIT_FAILURE);
-      }
-      break;
-    case 'n':
-      envflags |= MDBX_NOSUBDIR;
-      break;
-    case 'p':
-      mode |= PRINT;
-      break;
-    case 's':
-      if (alldbs)
-        usage();
-      subname = optarg;
-      break;
-    case 'q':
-      quiet = true;
-      break;
-    case 'r':
-      rescue = true;
-      break;
-    default:
-      usage();
-    }
-  }
-
-  if (optind != argc - 1)
-    usage();
-
-#if defined(_WIN32) || defined(_WIN64)
-  SetConsoleCtrlHandler(ConsoleBreakHandlerRoutine, true);
-#else
-#ifdef SIGPIPE
-  signal(SIGPIPE, signal_handler);
-#endif
-#ifdef SIGHUP
-  signal(SIGHUP, signal_handler);
-#endif
-  signal(SIGINT, signal_handler);
-  signal(SIGTERM, signal_handler);
-#endif /* !WINDOWS */
-
-  envname = argv[optind];
-  if (!quiet) {
-    fprintf(stderr, "mdbx_dump %s (%s, T-%s)\nRunning for %s...\n",
-            mdbx_version.git.describe, mdbx_version.git.datetime,
-            mdbx_version.git.tree, envname);
-    fflush(nullptr);
-  }
-
-  rc = mdbx_env_create(&env);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_create", rc);
-    return EXIT_FAILURE;
-  }
-
-  if (alldbs || subname) {
-    rc = mdbx_env_set_maxdbs(env, 2);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_env_set_maxdbs", rc);
-      goto env_close;
-    }
-  }
-
-  rc = mdbx_env_open(
-      env, envname,
-      envflags | (rescue ? MDBX_RDONLY | MDBX_EXCLUSIVE : MDBX_RDONLY), 0);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_open", rc);
-    goto env_close;
-  }
-
-  rc = mdbx_txn_begin(env, nullptr, MDBX_TXN_RDONLY, &txn);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_txn_begin", rc);
-    goto env_close;
-  }
-
-  rc = mdbx_dbi_open(txn, subname, MDBX_DB_ACCEDE, &dbi);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_dbi_open", rc);
-    goto txn_abort;
-  }
-
-  if (alldbs) {
-    assert(dbi == MAIN_DBI);
-
-    MDBX_cursor *cursor;
-    rc = mdbx_cursor_open(txn, MAIN_DBI, &cursor);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_cursor_open", rc);
-      goto txn_abort;
-    }
-    if (MDBX_DEBUG > 0 && rescue) {
-      cursor->mc_flags |= C_SKIPORD;
-      if (cursor->mc_xcursor)
-        cursor->mc_xcursor->mx_cursor.mc_flags |= C_SKIPORD;
-    }
-
-    bool have_raw = false;
-    int count = 0;
-    MDBX_val key;
-    while (MDBX_SUCCESS ==
-           (rc = mdbx_cursor_get(cursor, &key, nullptr, MDBX_NEXT_NODUP))) {
-      if (user_break) {
-        rc = MDBX_EINTR;
-        break;
-      }
-
-      if (memchr(key.iov_base, '\0', key.iov_len))
-        continue;
-      subname = mdbx_realloc(buf4free, key.iov_len + 1);
-      if (!subname) {
-        rc = MDBX_ENOMEM;
-        break;
-      }
-
-      buf4free = subname;
-      memcpy(subname, key.iov_base, key.iov_len);
-      subname[key.iov_len] = '\0';
-
-      MDBX_dbi sub_dbi;
-      rc = mdbx_dbi_open_ex(txn, subname, MDBX_DB_ACCEDE, &sub_dbi,
-                            rescue ? equal_or_greater : nullptr,
-                            rescue ? equal_or_greater : nullptr);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        if (rc == MDBX_INCOMPATIBLE) {
-          have_raw = true;
-          continue;
-        }
-        error("mdbx_dbi_open", rc);
-        if (!rescue)
-          break;
-      } else {
-        count++;
-        if (list) {
-          printf("%s\n", subname);
-        } else {
-          rc = dump_sdb(txn, sub_dbi, subname);
-          if (unlikely(rc != MDBX_SUCCESS)) {
-            if (!rescue)
-              break;
-            fprintf(stderr, "%s: %s: ignore %s for `%s` and continue\n", prog,
-                    envname, mdbx_strerror(rc), subname);
-            /* Here is a hack for rescue mode, don't do that:
-             *  - we should restart transaction in case error due
-             *    database corruption;
-             *  - but we won't close cursor, reopen and re-positioning it
-             *    for new a transaction;
-             *  - this is possible since DB is opened in read-only exclusive
-             *    mode and transaction is the same, i.e. has the same address
-             *    and so on. */
-            rc = mdbx_txn_reset(txn);
-            if (unlikely(rc != MDBX_SUCCESS)) {
-              error("mdbx_txn_reset", rc);
-              goto env_close;
-            }
-            rc = mdbx_txn_renew(txn);
-            if (unlikely(rc != MDBX_SUCCESS)) {
-              error("mdbx_txn_renew", rc);
-              goto env_close;
-            }
-          }
-        }
-        rc = mdbx_dbi_close(env, sub_dbi);
-        if (unlikely(rc != MDBX_SUCCESS)) {
-          error("mdbx_dbi_close", rc);
-          break;
-        }
-      }
-    }
-    mdbx_cursor_close(cursor);
-    cursor = nullptr;
-
-    if (have_raw && (!count /* || rescue */))
-      rc = dump_sdb(txn, MAIN_DBI, nullptr);
-    else if (!count) {
-      fprintf(stderr, "%s: %s does not contain multiple databases\n", prog,
-              envname);
-      rc = MDBX_NOTFOUND;
-    }
-  } else {
-    rc = dump_sdb(txn, dbi, subname);
-  }
-
-  switch (rc) {
-  case MDBX_NOTFOUND:
-    rc = MDBX_SUCCESS;
-  case MDBX_SUCCESS:
-    break;
-  case MDBX_EINTR:
-    fprintf(stderr, "Interrupted by signal/user\n");
-    break;
-  default:
-    if (unlikely(rc != MDBX_SUCCESS))
-      error("mdbx_cursor_get", rc);
-  }
-
-  mdbx_dbi_close(env, dbi);
-txn_abort:
-  mdbx_txn_abort(txn);
-env_close:
-  mdbx_env_close(env);
-  free(buf4free);
-
-  return rc ? EXIT_FAILURE : EXIT_SUCCESS;
-}
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx_load.c b/plugins/Dbx_mdbx/src/libmdbx/mdbx_load.c
deleted file mode 100644
index fc0021bf1c..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx_load.c
+++ /dev/null
@@ -1,3965 +0,0 @@
-/* mdbx_load.c - memory-mapped database load tool */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#ifdef _MSC_VER
-#if _MSC_VER > 1800
-#pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#pragma warning(disable : 4996) /* The POSIX name is deprecated... */
-#endif                          /* _MSC_VER (warnings) */
-
-#define MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-
-#include <ctype.h>
-
-#if defined(_WIN32) || defined(_WIN64)
-/*
- * POSIX getopt for Windows
- *
- * AT&T Public License
- *
- * Code given out at the 1985 UNIFORUM conference in Dallas.
- */
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#endif /* _MSC_VER (warnings) */
-
-#include <stdio.h>
-#include <string.h>
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-/*----------------------------------------------------------------------------*/
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-#ifndef EOF
-#define EOF (-1)
-#endif
-
-int optind = 1;
-int optopt;
-char *optarg;
-
-int getopt(int argc, char *const argv[], const char *opts) {
-  static int sp = 1;
-  int c;
-  const char *cp;
-
-  if (sp == 1) {
-    if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0')
-      return EOF;
-    else if (strcmp(argv[optind], "--") == 0) {
-      optind++;
-      return EOF;
-    }
-  }
-  optopt = c = argv[optind][sp];
-  if (c == ':' || (cp = strchr(opts, c)) == NULL) {
-    fprintf(stderr, "%s: %s -- %c\n", argv[0], "illegal option", c);
-    if (argv[optind][++sp] == '\0') {
-      optind++;
-      sp = 1;
-    }
-    return '?';
-  }
-  if (*++cp == ':') {
-    if (argv[optind][sp + 1] != '\0')
-      optarg = &argv[optind++][sp + 1];
-    else if (++optind >= argc) {
-      fprintf(stderr, "%s: %s -- %c\n", argv[0], "option requires an argument",
-              c);
-      sp = 1;
-      return '?';
-    } else
-      optarg = argv[optind++];
-    sp = 1;
-  } else {
-    if (argv[optind][++sp] == '\0') {
-      sp = 1;
-      optind++;
-    }
-    optarg = NULL;
-  }
-  return c;
-}
-
-static volatile BOOL user_break;
-static BOOL WINAPI ConsoleBreakHandlerRoutine(DWORD dwCtrlType) {
-  (void)dwCtrlType;
-  user_break = true;
-  return true;
-}
-
-#else /* WINDOWS */
-
-static volatile sig_atomic_t user_break;
-static void signal_handler(int sig) {
-  (void)sig;
-  user_break = 1;
-}
-
-#endif /* !WINDOWS */
-
-static char *prog;
-static size_t lineno;
-static void error(const char *func, int rc) {
-  if (lineno)
-    fprintf(stderr, "%s: at input line %" PRIiSIZE ": %s() error %d, %s\n",
-            prog, lineno, func, rc, mdbx_strerror(rc));
-  else
-    fprintf(stderr, "%s: %s() error %d %s\n", prog, func, rc,
-            mdbx_strerror(rc));
-}
-
-static char *valstr(char *line, const char *item) {
-  const size_t len = strlen(item);
-  if (strncmp(line, item, len) != 0)
-    return nullptr;
-  if (line[len] != '=') {
-    if (line[len] > ' ')
-      return nullptr;
-    fprintf(stderr, "%s: line %" PRIiSIZE ": unexpected line format for '%s'\n",
-            prog, lineno, item);
-    exit(EXIT_FAILURE);
-  }
-  char *ptr = strchr(line, '\n');
-  if (ptr)
-    *ptr = '\0';
-  return line + len + 1;
-}
-
-static bool valnum(char *line, const char *item, uint64_t *value) {
-  char *str = valstr(line, item);
-  if (!str)
-    return false;
-
-  char *end = nullptr;
-  *value = strtoull(str, &end, 0);
-  if (end && *end) {
-    fprintf(stderr,
-            "%s: line %" PRIiSIZE ": unexpected number format for '%s'\n", prog,
-            lineno, item);
-    exit(EXIT_FAILURE);
-  }
-  return true;
-}
-
-static bool valbool(char *line, const char *item, bool *value) {
-  uint64_t u64;
-  if (!valnum(line, item, &u64))
-    return false;
-
-  if (u64 > 1) {
-    fprintf(stderr, "%s: line %" PRIiSIZE ": unexpected value for '%s'\n", prog,
-            lineno, item);
-    exit(EXIT_FAILURE);
-  }
-  *value = u64 != 0;
-  return true;
-}
-
-/*----------------------------------------------------------------------------*/
-
-static char *subname = nullptr;
-static int dbi_flags;
-static txnid_t txnid;
-static uint64_t sequence;
-static MDBX_canary canary;
-static MDBX_envinfo envinfo;
-
-#define PRINT 1
-#define NOHDR 2
-#define GLOBAL 4
-static int mode = GLOBAL;
-
-static MDBX_val kbuf, dbuf;
-
-#define STRLENOF(s) (sizeof(s) - 1)
-
-typedef struct flagbit {
-  unsigned bit;
-  char *name;
-  unsigned len;
-} flagbit;
-
-#define S(s) s, STRLENOF(s)
-
-flagbit dbflags[] = {
-    {MDBX_REVERSEKEY, S("reversekey")}, {MDBX_DUPSORT, S("duplicates")},
-    {MDBX_DUPSORT, S("dupsort")},       {MDBX_INTEGERKEY, S("integerkey")},
-    {MDBX_DUPFIXED, S("dupfixed")},     {MDBX_INTEGERDUP, S("integerdup")},
-    {MDBX_REVERSEDUP, S("reversedup")}, {0, nullptr, 0}};
-
-static int readhdr(void) {
-  /* reset parameters */
-  if (subname) {
-    free(subname);
-    subname = nullptr;
-  }
-  dbi_flags = 0;
-  txnid = 0;
-  sequence = 0;
-
-  while (true) {
-    errno = 0;
-    if (fgets(dbuf.iov_base, (int)dbuf.iov_len, stdin) == nullptr)
-      return errno ? errno : EOF;
-    if (user_break)
-      return MDBX_EINTR;
-
-    lineno++;
-    uint64_t u64;
-
-    if (valnum(dbuf.iov_base, "VERSION", &u64)) {
-      if (u64 != 3) {
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": unsupported value %" PRIu64
-                " for %s\n",
-                prog, lineno, u64, "VERSION");
-        exit(EXIT_FAILURE);
-      }
-      continue;
-    }
-
-    if (valnum(dbuf.iov_base, "db_pagesize", &u64)) {
-      if (!(mode & GLOBAL) && envinfo.mi_dxb_pagesize != u64)
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore value %" PRIu64
-                " for '%s' in non-global context\n",
-                prog, lineno, u64, "db_pagesize");
-      else if (u64 < MDBX_MIN_PAGESIZE || u64 > MDBX_MAX_PAGESIZE)
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore unsupported value %" PRIu64
-                " for %s\n",
-                prog, lineno, u64, "db_pagesize");
-      else
-        envinfo.mi_dxb_pagesize = (uint32_t)u64;
-      continue;
-    }
-
-    char *str = valstr(dbuf.iov_base, "format");
-    if (str) {
-      if (strcmp(str, "print") == 0) {
-        mode |= PRINT;
-        continue;
-      }
-      if (strcmp(str, "bytevalue") == 0) {
-        mode &= ~PRINT;
-        continue;
-      }
-      fprintf(stderr, "%s: line %" PRIiSIZE ": unsupported value '%s' for %s\n",
-              prog, lineno, str, "format");
-      exit(EXIT_FAILURE);
-    }
-
-    str = valstr(dbuf.iov_base, "database");
-    if (str) {
-      if (*str) {
-        free(subname);
-        subname = mdbx_strdup(str);
-        if (!subname) {
-          perror("strdup()");
-          exit(EXIT_FAILURE);
-        }
-      }
-      continue;
-    }
-
-    str = valstr(dbuf.iov_base, "type");
-    if (str) {
-      if (strcmp(str, "btree") != 0) {
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": unsupported value '%s' for %s\n", prog,
-                lineno, str, "type");
-        free(subname);
-        exit(EXIT_FAILURE);
-      }
-      continue;
-    }
-
-    if (valnum(dbuf.iov_base, "mapaddr", &u64)) {
-      if (u64)
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore unsupported value 0x%" PRIx64
-                " for %s\n",
-                prog, lineno, u64, "mapaddr");
-      continue;
-    }
-
-    if (valnum(dbuf.iov_base, "mapsize", &u64)) {
-      if (!(mode & GLOBAL))
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore value %" PRIu64
-                " for '%s' in non-global context\n",
-                prog, lineno, u64, "mapsize");
-      else if (u64 < MIN_MAPSIZE || u64 > MAX_MAPSIZE64)
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore unsupported value 0x%" PRIx64
-                " for %s\n",
-                prog, lineno, u64, "mapsize");
-      else
-        envinfo.mi_mapsize = (size_t)u64;
-      continue;
-    }
-
-    if (valnum(dbuf.iov_base, "maxreaders", &u64)) {
-      if (!(mode & GLOBAL))
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore value %" PRIu64
-                " for '%s' in non-global context\n",
-                prog, lineno, u64, "maxreaders");
-      else if (u64 < 1 || u64 > MDBX_READERS_LIMIT)
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore unsupported value 0x%" PRIx64
-                " for %s\n",
-                prog, lineno, u64, "maxreaders");
-      else
-        envinfo.mi_maxreaders = (int)u64;
-      continue;
-    }
-
-    if (valnum(dbuf.iov_base, "txnid", &u64)) {
-      if (u64 < MIN_TXNID || u64 > MAX_TXNID)
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore unsupported value 0x%" PRIx64
-                " for %s\n",
-                prog, lineno, u64, "txnid");
-      txnid = u64;
-      continue;
-    }
-
-    if (valnum(dbuf.iov_base, "sequence", &u64)) {
-      sequence = u64;
-      continue;
-    }
-
-    str = valstr(dbuf.iov_base, "geometry");
-    if (str) {
-      if (!(mode & GLOBAL))
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore values %s"
-                " for '%s' in non-global context\n",
-                prog, lineno, str, "geometry");
-      else if (sscanf(str,
-                      "l%" PRIu64 ",c%" PRIu64 ",u%" PRIu64 ",s%" PRIu64
-                      ",g%" PRIu64,
-                      &envinfo.mi_geo.lower, &envinfo.mi_geo.current,
-                      &envinfo.mi_geo.upper, &envinfo.mi_geo.shrink,
-                      &envinfo.mi_geo.grow) != 5) {
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": unexpected line format for '%s'\n",
-                prog, lineno, "geometry");
-        exit(EXIT_FAILURE);
-      }
-      continue;
-    }
-
-    str = valstr(dbuf.iov_base, "canary");
-    if (str) {
-      if (!(mode & GLOBAL))
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": ignore values %s"
-                " for '%s' in non-global context\n",
-                prog, lineno, str, "canary");
-      else if (sscanf(str, "v%" PRIu64 ",x%" PRIu64 ",y%" PRIu64 ",z%" PRIu64,
-                      &canary.v, &canary.x, &canary.y, &canary.z) != 4) {
-        fprintf(stderr,
-                "%s: line %" PRIiSIZE ": unexpected line format for '%s'\n",
-                prog, lineno, "canary");
-        exit(EXIT_FAILURE);
-      }
-      continue;
-    }
-
-    for (int i = 0; dbflags[i].bit; i++) {
-      bool value = false;
-      if (valbool(dbuf.iov_base, dbflags[i].name, &value)) {
-        if (value)
-          dbi_flags |= dbflags[i].bit;
-        else
-          dbi_flags &= ~dbflags[i].bit;
-        goto next;
-      }
-    }
-
-    str = valstr(dbuf.iov_base, "HEADER");
-    if (str) {
-      if (strcmp(str, "END") == 0)
-        return MDBX_SUCCESS;
-    }
-
-    fprintf(stderr,
-            "%s: line %" PRIiSIZE ": unrecognized keyword ignored: %s\n", prog,
-            lineno, (char *)dbuf.iov_base);
-  next:;
-  }
-  return EOF;
-}
-
-static int badend(void) {
-  fprintf(stderr, "%s: line %" PRIiSIZE ": unexpected end of input\n", prog,
-          lineno);
-  return errno ? errno : MDBX_ENODATA;
-}
-
-static int unhex(unsigned char *c2) {
-  int x, c;
-  x = *c2++ & 0x4f;
-  if (x & 0x40)
-    x -= 55;
-  c = x << 4;
-  x = *c2 & 0x4f;
-  if (x & 0x40)
-    x -= 55;
-  c |= x;
-  return c;
-}
-
-static int readline(MDBX_val *out, MDBX_val *buf) {
-  unsigned char *c1, *c2, *end;
-  size_t len, l2;
-  int c;
-
-  if (user_break)
-    return MDBX_EINTR;
-
-  errno = 0;
-  if (!(mode & NOHDR)) {
-    c = fgetc(stdin);
-    if (c == EOF)
-      return errno ? errno : EOF;
-    if (c != ' ') {
-      lineno++;
-      errno = 0;
-      if (fgets(buf->iov_base, (int)buf->iov_len, stdin)) {
-        if (c == 'D' && !strncmp(buf->iov_base, "ATA=END", STRLENOF("ATA=END")))
-          return EOF;
-      }
-      return badend();
-    }
-  }
-  if (fgets(buf->iov_base, (int)buf->iov_len, stdin) == nullptr)
-    return errno ? errno : EOF;
-  lineno++;
-
-  c1 = buf->iov_base;
-  len = strlen((char *)c1);
-  l2 = len;
-
-  /* Is buffer too short? */
-  while (c1[len - 1] != '\n') {
-    buf->iov_base = mdbx_realloc(buf->iov_base, buf->iov_len * 2);
-    if (!buf->iov_base) {
-      fprintf(stderr, "%s: line %" PRIiSIZE ": out of memory, line too long\n",
-              prog, lineno);
-      return MDBX_ENOMEM;
-    }
-    c1 = buf->iov_base;
-    c1 += l2;
-    errno = 0;
-    if (fgets((char *)c1, (int)buf->iov_len + 1, stdin) == nullptr)
-      return errno ? errno : EOF;
-    buf->iov_len *= 2;
-    len = strlen((char *)c1);
-    l2 += len;
-  }
-  c1 = c2 = buf->iov_base;
-  len = l2;
-  c1[--len] = '\0';
-  end = c1 + len;
-
-  if (mode & PRINT) {
-    while (c2 < end) {
-      if (unlikely(*c2 == '\\')) {
-        if (c2[1] == '\\') {
-          *c1++ = '\\';
-        } else {
-          if (c2 + 3 > end || !isxdigit(c2[1]) || !isxdigit(c2[2]))
-            return badend();
-          *c1++ = (char)unhex(++c2);
-        }
-        c2 += 2;
-      } else {
-        /* copies are redundant when no escapes were used */
-        *c1++ = *c2++;
-      }
-    }
-  } else {
-    /* odd length not allowed */
-    if (len & 1)
-      return badend();
-    while (c2 < end) {
-      if (!isxdigit(*c2) || !isxdigit(c2[1]))
-        return badend();
-      *c1++ = (char)unhex(c2);
-      c2 += 2;
-    }
-  }
-  c2 = out->iov_base = buf->iov_base;
-  out->iov_len = c1 - c2;
-
-  return MDBX_SUCCESS;
-}
-
-static void usage(void) {
-  fprintf(stderr,
-          "usage: %s "
-          "[-V] [-q] [-a] [-f file] [-s name] [-N] [-p] [-T] [-r] [-n] dbpath\n"
-          "  -V\t\tprint version and exit\n"
-          "  -q\t\tbe quiet\n"
-          "  -a\t\tappend records in input order (required for custom "
-          "comparators)\n"
-          "  -f file\tread from file instead of stdin\n"
-          "  -s name\tload into named subDB\n"
-          "  -N\t\tdon't overwrite existing records when loading, just skip "
-          "ones\n"
-          "  -p\t\tpurge subDB before loading\n"
-          "  -T\t\tread plaintext\n"
-          "  -r\t\trescue mode (ignore errors to load corrupted DB dump)\n"
-          "  -n\t\tdon't use subdirectory for newly created database "
-          "(MDBX_NOSUBDIR)\n",
-          prog);
-  exit(EXIT_FAILURE);
-}
-
-static int equal_or_greater(const MDBX_val *a, const MDBX_val *b) {
-  return (a->iov_len == b->iov_len &&
-          memcmp(a->iov_base, b->iov_base, a->iov_len) == 0)
-             ? 0
-             : 1;
-}
-
-int main(int argc, char *argv[]) {
-  int i, rc;
-  MDBX_env *env = nullptr;
-  MDBX_txn *txn = nullptr;
-  MDBX_cursor *mc = nullptr;
-  MDBX_dbi dbi;
-  char *envname = nullptr;
-  int envflags = MDBX_SAFE_NOSYNC | MDBX_ACCEDE, putflags = MDBX_UPSERT;
-  bool quiet = false;
-  bool rescue = false;
-  bool purge = false;
-
-  prog = argv[0];
-  if (argc < 2)
-    usage();
-
-  while ((i = getopt(argc, argv,
-                     "a"
-                     "f:"
-                     "n"
-                     "s:"
-                     "N"
-                     "p"
-                     "T"
-                     "V"
-                     "r"
-                     "q")) != EOF) {
-    switch (i) {
-    case 'V':
-      printf("mdbx_load version %d.%d.%d.%d\n"
-             " - source: %s %s, commit %s, tree %s\n"
-             " - anchor: %s\n"
-             " - build: %s for %s by %s\n"
-             " - flags: %s\n"
-             " - options: %s\n",
-             mdbx_version.major, mdbx_version.minor, mdbx_version.release,
-             mdbx_version.revision, mdbx_version.git.describe,
-             mdbx_version.git.datetime, mdbx_version.git.commit,
-             mdbx_version.git.tree, mdbx_sourcery_anchor, mdbx_build.datetime,
-             mdbx_build.target, mdbx_build.compiler, mdbx_build.flags,
-             mdbx_build.options);
-      return EXIT_SUCCESS;
-    case 'a':
-      putflags |= MDBX_APPEND;
-      break;
-    case 'f':
-      if (freopen(optarg, "r", stdin) == nullptr) {
-        fprintf(stderr, "%s: %s: open: %s\n", prog, optarg,
-                mdbx_strerror(errno));
-        exit(EXIT_FAILURE);
-      }
-      break;
-    case 'n':
-      envflags |= MDBX_NOSUBDIR;
-      break;
-    case 's':
-      subname = mdbx_strdup(optarg);
-      break;
-    case 'N':
-      putflags |= MDBX_NOOVERWRITE | MDBX_NODUPDATA;
-      break;
-    case 'p':
-      purge = true;
-      break;
-    case 'T':
-      mode |= NOHDR | PRINT;
-      break;
-    case 'q':
-      quiet = true;
-      break;
-    case 'r':
-      rescue = true;
-      break;
-    default:
-      usage();
-    }
-  }
-
-  if (optind != argc - 1)
-    usage();
-
-#if defined(_WIN32) || defined(_WIN64)
-  SetConsoleCtrlHandler(ConsoleBreakHandlerRoutine, true);
-#else
-#ifdef SIGPIPE
-  signal(SIGPIPE, signal_handler);
-#endif
-#ifdef SIGHUP
-  signal(SIGHUP, signal_handler);
-#endif
-  signal(SIGINT, signal_handler);
-  signal(SIGTERM, signal_handler);
-#endif /* !WINDOWS */
-
-  envname = argv[optind];
-  if (!quiet)
-    printf("mdbx_load %s (%s, T-%s)\nRunning for %s...\n",
-           mdbx_version.git.describe, mdbx_version.git.datetime,
-           mdbx_version.git.tree, envname);
-  fflush(nullptr);
-
-  dbuf.iov_len = 4096;
-  dbuf.iov_base = mdbx_malloc(dbuf.iov_len);
-  if (!dbuf.iov_base) {
-    rc = MDBX_ENOMEM;
-    error("value-buffer", rc);
-    goto env_close;
-  }
-
-  /* read first header for mapsize= */
-  if (!(mode & NOHDR)) {
-    rc = readhdr();
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      if (rc == EOF)
-        rc = MDBX_ENODATA;
-      error("readheader", rc);
-      goto env_close;
-    }
-  }
-
-  rc = mdbx_env_create(&env);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_create", rc);
-    return EXIT_FAILURE;
-  }
-
-  mdbx_env_set_maxdbs(env, 2);
-  if (envinfo.mi_maxreaders) {
-    rc = mdbx_env_set_maxreaders(env, envinfo.mi_maxreaders);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_env_set_maxreaders", rc);
-      goto env_close;
-    }
-  }
-
-  if (envinfo.mi_geo.current | envinfo.mi_mapsize) {
-    if (envinfo.mi_geo.current) {
-      rc = mdbx_env_set_geometry(
-          env, (intptr_t)envinfo.mi_geo.lower, (intptr_t)envinfo.mi_geo.current,
-          (intptr_t)envinfo.mi_geo.upper, (intptr_t)envinfo.mi_geo.shrink,
-          (intptr_t)envinfo.mi_geo.grow,
-          envinfo.mi_dxb_pagesize ? (intptr_t)envinfo.mi_dxb_pagesize : -1);
-    } else {
-      if (envinfo.mi_mapsize > MAX_MAPSIZE) {
-        fprintf(
-            stderr,
-            "Database size is too large for current system (mapsize=%" PRIu64
-            " is great than system-limit %zu)\n",
-            envinfo.mi_mapsize, (size_t)MAX_MAPSIZE);
-        goto env_close;
-      }
-      rc = mdbx_env_set_geometry(
-          env, (intptr_t)envinfo.mi_mapsize, (intptr_t)envinfo.mi_mapsize,
-          (intptr_t)envinfo.mi_mapsize, 0, 0,
-          envinfo.mi_dxb_pagesize ? (intptr_t)envinfo.mi_dxb_pagesize : -1);
-    }
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_env_set_geometry", rc);
-      goto env_close;
-    }
-  }
-
-  rc = mdbx_env_open(env, envname, envflags, 0664);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_open", rc);
-    goto env_close;
-  }
-
-  kbuf.iov_len = mdbx_env_get_maxvalsize_ex(env, 0) + 1;
-  if (kbuf.iov_len >= INTPTR_MAX / 2) {
-    fprintf(stderr, "mdbx_env_get_maxkeysize() failed, returns %zu\n",
-            kbuf.iov_len);
-    goto env_close;
-  }
-
-  kbuf.iov_base = malloc(kbuf.iov_len);
-  if (!kbuf.iov_base) {
-    rc = MDBX_ENOMEM;
-    error("key-buffer", rc);
-    goto env_close;
-  }
-
-  while (rc == MDBX_SUCCESS) {
-    if (user_break) {
-      rc = MDBX_EINTR;
-      break;
-    }
-
-    rc = mdbx_txn_begin(env, nullptr, 0, &txn);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_txn_begin", rc);
-      goto env_close;
-    }
-
-    if (mode & GLOBAL) {
-      mode -= GLOBAL;
-      if (canary.v | canary.x | canary.y | canary.z) {
-        rc = mdbx_canary_put(txn, &canary);
-        if (unlikely(rc != MDBX_SUCCESS)) {
-          error("mdbx_canary_put", rc);
-          goto txn_abort;
-        }
-      }
-    }
-
-    const char *const dbi_name = subname ? subname : "@MAIN";
-    rc =
-        mdbx_dbi_open_ex(txn, subname, dbi_flags | MDBX_CREATE, &dbi,
-                         (putflags & MDBX_APPEND) ? equal_or_greater : nullptr,
-                         (putflags & MDBX_APPEND) ? equal_or_greater : nullptr);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_dbi_open_ex", rc);
-      goto txn_abort;
-    }
-
-    uint64_t present_sequence;
-    rc = mdbx_dbi_sequence(txn, dbi, &present_sequence, 0);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_dbi_sequence", rc);
-      goto txn_abort;
-    }
-    if (present_sequence > sequence) {
-      fprintf(stderr,
-              "present sequence for '%s' value (%" PRIu64
-              ") is greater than loaded (%" PRIu64 ")\n",
-              dbi_name, present_sequence, sequence);
-      rc = MDBX_RESULT_TRUE;
-      goto txn_abort;
-    }
-    if (present_sequence < sequence) {
-      rc = mdbx_dbi_sequence(txn, dbi, nullptr, sequence - present_sequence);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_dbi_sequence", rc);
-        goto txn_abort;
-      }
-    }
-
-    if (purge) {
-      rc = mdbx_drop(txn, dbi, false);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_drop", rc);
-        goto txn_abort;
-      }
-    }
-
-    if (putflags & MDBX_APPEND)
-      putflags = (dbi_flags & MDBX_DUPSORT) ? putflags | MDBX_APPENDDUP
-                                            : putflags & ~MDBX_APPENDDUP;
-
-    rc = mdbx_cursor_open(txn, dbi, &mc);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_cursor_open", rc);
-      goto txn_abort;
-    }
-
-    int batch = 0;
-    while (rc == MDBX_SUCCESS) {
-      MDBX_val key, data;
-      rc = readline(&key, &kbuf);
-      if (rc == EOF)
-        break;
-
-      if (rc == MDBX_SUCCESS)
-        rc = readline(&data, &dbuf);
-      if (rc) {
-        fprintf(stderr, "%s: line %" PRIiSIZE ": failed to read key value\n",
-                prog, lineno);
-        goto txn_abort;
-      }
-
-      rc = mdbx_cursor_put(mc, &key, &data, putflags);
-      if (rc == MDBX_KEYEXIST && putflags)
-        continue;
-      if (rc == MDBX_BAD_VALSIZE && rescue) {
-        fprintf(stderr, "%s: skip line %" PRIiSIZE ": due %s\n", prog, lineno,
-                mdbx_strerror(rc));
-        continue;
-      }
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_cursor_put", rc);
-        goto txn_abort;
-      }
-      batch++;
-
-      MDBX_txn_info txn_info;
-      rc = mdbx_txn_info(txn, &txn_info, false);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_txn_info", rc);
-        goto txn_abort;
-      }
-
-      if (batch == 10000 || txn_info.txn_space_dirty > MEGABYTE * 256) {
-        rc = mdbx_txn_commit(txn);
-        if (unlikely(rc != MDBX_SUCCESS)) {
-          error("mdbx_txn_commit", rc);
-          goto env_close;
-        }
-        batch = 0;
-
-        rc = mdbx_txn_begin(env, nullptr, 0, &txn);
-        if (unlikely(rc != MDBX_SUCCESS)) {
-          error("mdbx_txn_begin", rc);
-          goto env_close;
-        }
-        rc = mdbx_cursor_bind(txn, mc, dbi);
-        if (unlikely(rc != MDBX_SUCCESS)) {
-          error("mdbx_cursor_bind", rc);
-          goto txn_abort;
-        }
-      }
-    }
-
-    mdbx_cursor_close(mc);
-    mc = nullptr;
-    rc = mdbx_txn_commit(txn);
-    txn = nullptr;
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_txn_commit", rc);
-      goto env_close;
-    }
-    if (subname) {
-      assert(dbi != MAIN_DBI);
-      rc = mdbx_dbi_close(env, dbi);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_dbi_close", rc);
-        goto env_close;
-      }
-    } else {
-      assert(dbi == MAIN_DBI);
-    }
-
-    /* try read next header */
-    if (!(mode & NOHDR))
-      rc = readhdr();
-    else if (ferror(stdin) || feof(stdin))
-      break;
-  }
-
-  switch (rc) {
-  case EOF:
-    rc = MDBX_SUCCESS;
-  case MDBX_SUCCESS:
-    break;
-  case MDBX_EINTR:
-    fprintf(stderr, "Interrupted by signal/user\n");
-    break;
-  default:
-    if (unlikely(rc != MDBX_SUCCESS))
-      error("readline", rc);
-  }
-
-txn_abort:
-  mdbx_cursor_close(mc);
-  mdbx_txn_abort(txn);
-env_close:
-  mdbx_env_close(env);
-  free(kbuf.iov_base);
-  free(dbuf.iov_base);
-
-  return rc ? EXIT_FAILURE : EXIT_SUCCESS;
-}
diff --git a/plugins/Dbx_mdbx/src/libmdbx/mdbx_stat.c b/plugins/Dbx_mdbx/src/libmdbx/mdbx_stat.c
deleted file mode 100644
index 30e9e5cc29..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/mdbx_stat.c
+++ /dev/null
@@ -1,3611 +0,0 @@
-/* mdbx_stat.c - memory-mapped database status tool */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#ifdef _MSC_VER
-#if _MSC_VER > 1800
-#pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#pragma warning(disable : 4996) /* The POSIX name is deprecated... */
-#endif                          /* _MSC_VER (warnings) */
-
-#define MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>. */
-
-#define MDBX_BUILD_SOURCERY 37ec6726f69ef69c4e52fcfb87d700f44f37246b1b635f455d2a429776a8eec6_v0_9_2_136_g9f0ff86
-#ifdef MDBX_CONFIG_H
-#include MDBX_CONFIG_H
-#endif
-
-#define LIBMDBX_INTERNALS
-#ifdef MDBX_TOOLS
-#define MDBX_DEPRECATED
-#endif /* MDBX_TOOLS */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-/* In case the MDBX_DEBUG is undefined set it corresponding to NDEBUG */
-#ifndef MDBX_DEBUG
-#   ifdef NDEBUG
-#       define MDBX_DEBUG 0
-#   else
-#       define MDBX_DEBUG 1
-#   endif
-#endif
-
-/* Undefine the NDEBUG if debugging is enforced by MDBX_DEBUG */
-#if MDBX_DEBUG
-#   undef NDEBUG
-#endif
-
-#ifdef MDBX_ALLOY
-/* Amalgamated build */
-#   define MDBX_INTERNAL_FUNC static
-#   define MDBX_INTERNAL_VAR static
-#else
-/* Non-amalgamated build */
-#   define MDBX_INTERNAL_FUNC
-#   define MDBX_INTERNAL_VAR extern
-#endif /* MDBX_ALLOY */
-
-#ifndef MDBX_DISABLE_GNU_SOURCE
-#define MDBX_DISABLE_GNU_SOURCE 0
-#endif
-#if MDBX_DISABLE_GNU_SOURCE
-#undef _GNU_SOURCE
-#elif (defined(__linux__) || defined(__gnu_linux__)) && !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-/* Should be defined before any includes */
-#ifndef _FILE_OFFSET_BITS
-#   define _FILE_OFFSET_BITS 64
-#endif
-
-#ifdef __APPLE__
-#define _DARWIN_C_SOURCE
-#endif
-
-#ifdef _MSC_VER
-#   if _MSC_FULL_VER < 190024234
-        /* Actually libmdbx was not tested with compilers older than 19.00.24234 (Visual Studio 2015 Update 3).
-         * But you could remove this #error and try to continue at your own risk.
-         * In such case please don't rise up an issues related ONLY to old compilers.
-         */
-#       error "At least \"Microsoft C/C++ Compiler\" version 19.00.24234 (Visual Studio 2015 Update 3) is required."
-#   endif
-#   ifndef _CRT_SECURE_NO_WARNINGS
-#       define _CRT_SECURE_NO_WARNINGS
-#   endif
-#if _MSC_VER > 1800
-#   pragma warning(disable : 4464) /* relative include path contains '..' */
-#endif
-#if _MSC_VER > 1913
-#   pragma warning(disable : 5045) /* Compiler will insert Spectre mitigation... */
-#endif
-#pragma warning(disable : 4710) /* 'xyz': function not inlined */
-#pragma warning(disable : 4711) /* function 'xyz' selected for automatic inline expansion */
-#pragma warning(disable : 4201) /* nonstandard extension used : nameless struct / union */
-#pragma warning(disable : 4702) /* unreachable code */
-#pragma warning(disable : 4706) /* assignment within conditional expression */
-#pragma warning(disable : 4127) /* conditional expression is constant */
-#pragma warning(disable : 4324) /* 'xyz': structure was padded due to alignment specifier */
-#pragma warning(disable : 4310) /* cast truncates constant value */
-#pragma warning(disable : 4820) /* bytes padding added after data member for alignment */
-#pragma warning(disable : 4548) /* expression before comma has no effect; expected expression with side - effect */
-#pragma warning(disable : 4366) /* the result of the unary '&' operator may be unaligned */
-#pragma warning(disable : 4200) /* nonstandard extension used: zero-sized array in struct/union */
-#pragma warning(disable : 4204) /* nonstandard extension used: non-constant aggregate initializer */
-#pragma warning(disable : 4505) /* unreferenced local function has been removed */
-#endif                          /* _MSC_VER (warnings) */
-
-#include "mdbx.h"
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-
-#ifndef __GNUC_PREREQ
-#   if defined(__GNUC__) && defined(__GNUC_MINOR__)
-#       define __GNUC_PREREQ(maj, min) \
-          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GNUC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GNUC_PREREQ */
-
-#ifndef __CLANG_PREREQ
-#   ifdef __clang__
-#       define __CLANG_PREREQ(maj,min) \
-          ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min))
-#   else
-#       define __CLANG_PREREQ(maj,min) (0)
-#   endif
-#endif /* __CLANG_PREREQ */
-
-#ifndef __GLIBC_PREREQ
-#   if defined(__GLIBC__) && defined(__GLIBC_MINOR__)
-#       define __GLIBC_PREREQ(maj, min) \
-          ((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
-#   else
-#       define __GLIBC_PREREQ(maj, min) (0)
-#   endif
-#endif /* __GLIBC_PREREQ */
-
-#ifndef __has_warning
-#   define __has_warning(x) (0)
-#endif
-
-#ifndef __has_include
-#   define __has_include(x) (0)
-#endif
-
-#if __has_feature(thread_sanitizer)
-#   define __SANITIZE_THREAD__ 1
-#endif
-
-#if __has_feature(address_sanitizer)
-#   define __SANITIZE_ADDRESS__ 1
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __extern_C
-#   ifdef __cplusplus
-#       define __extern_C extern "C"
-#   else
-#       define __extern_C
-#   endif
-#endif /* __extern_C */
-
-#if !defined(nullptr) && !defined(__cplusplus) || (__cplusplus < 201103L && !defined(_MSC_VER))
-#   define nullptr NULL
-#endif
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef __always_inline
-#   if defined(__GNUC__) || __has_attribute(__always_inline__)
-#       define __always_inline __inline __attribute__((__always_inline__))
-#   elif defined(_MSC_VER)
-#       define __always_inline __forceinline
-#   else
-#       define __always_inline
-#   endif
-#endif /* __always_inline */
-
-#ifndef __noinline
-#   if defined(__GNUC__) || __has_attribute(__noinline__)
-#       define __noinline __attribute__((__noinline__))
-#   elif defined(_MSC_VER)
-#       define __noinline __declspec(noinline)
-#   else
-#       define __noinline
-#   endif
-#endif /* __noinline */
-
-#ifndef __must_check_result
-#   if defined(__GNUC__) || __has_attribute(__warn_unused_result__)
-#       define __must_check_result __attribute__((__warn_unused_result__))
-#   else
-#       define __must_check_result
-#   endif
-#endif /* __must_check_result */
-
-#ifndef __maybe_unused
-#   if defined(__GNUC__) || __has_attribute(__unused__)
-#       define __maybe_unused __attribute__((__unused__))
-#   else
-#       define __maybe_unused
-#   endif
-#endif /* __maybe_unused */
-
-#if !defined(__noop) && !defined(_MSC_VER)
-#   define __noop(...) do {} while(0)
-#endif /* __noop */
-
-#ifndef __fallthrough
-#  if defined(__cplusplus) && (__has_cpp_attribute(fallthrough) &&             \
-     (!defined(__clang__) || __clang__ > 4)) || __cplusplus >= 201703L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(8, 0) && defined(__cplusplus) && __cplusplus >= 201103L
-#    define __fallthrough [[fallthrough]]
-#  elif __GNUC_PREREQ(7, 0) &&                                                 \
-    (!defined(__LCC__) || (__LCC__ == 124 && __LCC_MINOR__ >= 12) ||           \
-     (__LCC__ == 125 && __LCC_MINOR__ >= 5) || (__LCC__ >= 126))
-#    define __fallthrough __attribute__((__fallthrough__))
-#  elif defined(__clang__) && defined(__cplusplus) && __cplusplus >= 201103L &&\
-    __has_feature(cxx_attributes) && __has_warning("-Wimplicit-fallthrough")
-#    define __fallthrough [[clang::fallthrough]]
-#  else
-#    define __fallthrough
-#  endif
-#endif /* __fallthrough */
-
-#ifndef __unreachable
-#   if __GNUC_PREREQ(4,5) || __has_builtin(__builtin_unreachable)
-#       define __unreachable() __builtin_unreachable()
-#   elif defined(_MSC_VER)
-#       define __unreachable() __assume(0)
-#   else
-#       define __unreachable() __noop()
-#   endif
-#endif /* __unreachable */
-
-#ifndef __prefetch
-#   if defined(__GNUC__) || defined(__clang__) || __has_builtin(__builtin_prefetch)
-#       define __prefetch(ptr) __builtin_prefetch(ptr)
-#   else
-#       define __prefetch(ptr) __noop(ptr)
-#   endif
-#endif /* __prefetch */
-
-#ifndef __nothrow
-#   if defined(__cplusplus)
-#       if __cplusplus < 201703L
-#           define __nothrow throw()
-#       else
-#           define __nothrow noexcept(true)
-#       endif /* __cplusplus */
-#   elif defined(__GNUC__) || __has_attribute(__nothrow__)
-#       define __nothrow __attribute__((__nothrow__))
-#   elif defined(_MSC_VER) && defined(__cplusplus)
-#       define __nothrow __declspec(nothrow)
-#   else
-#       define __nothrow
-#   endif
-#endif /* __nothrow */
-
-#ifndef __hidden
-#   if defined(__GNUC__) || __has_attribute(__visibility__)
-#       define __hidden __attribute__((__visibility__("hidden")))
-#   else
-#       define __hidden
-#   endif
-#endif /* __hidden */
-
-#ifndef __optimize
-#   if defined(__OPTIMIZE__)
-#       if (defined(__GNUC__) && !defined(__clang__)) || __has_attribute(__optimize__)
-#           define __optimize(ops) __attribute__((__optimize__(ops)))
-#       else
-#           define __optimize(ops)
-#       endif
-#   else
-#       define __optimize(ops)
-#   endif
-#endif /* __optimize */
-
-#ifndef __hot
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __hot __attribute__((__hot__)) __optimize(3)
-#       elif defined(__clang__) && !__has_attribute(__hot_) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put frequently used functions in separate section */
-#           define __hot __attribute__((__section__("text.hot"))) __optimize("O3")
-#       elif defined(__GNUC__) || __has_attribute(__hot__)
-#           define __hot __attribute__((__hot__)) __optimize("O3")
-#       else
-#           define __hot  __optimize("O3")
-#       endif
-#   else
-#       define __hot
-#   endif
-#endif /* __hot */
-
-#ifndef __cold
-#   if defined(__OPTIMIZE__)
-#       if defined(__e2k__)
-#           define __cold __attribute__((__cold__)) __optimize(1)
-#       elif defined(__clang__) && !__has_attribute(cold) \
-        && __has_attribute(__section__) && (defined(__linux__) || defined(__gnu_linux__))
-            /* just put infrequently used functions in separate section */
-#           define __cold __attribute__((__section__("text.unlikely"))) __optimize("Os")
-#       elif defined(__GNUC__) || __has_attribute(cold)
-#           define __cold __attribute__((__cold__)) __optimize("Os")
-#       else
-#           define __cold __optimize("Os")
-#       endif
-#   else
-#       define __cold
-#   endif
-#endif /* __cold */
-
-#ifndef __flatten
-#   if defined(__OPTIMIZE__) && (defined(__GNUC__) || __has_attribute(__flatten__))
-#       define __flatten __attribute__((__flatten__))
-#   else
-#       define __flatten
-#   endif
-#endif /* __flatten */
-
-#ifndef likely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define likely(cond) __builtin_expect(!!(cond), 1)
-#   else
-#       define likely(x) (!!(x))
-#   endif
-#endif /* likely */
-
-#ifndef unlikely
-#   if (defined(__GNUC__) || __has_builtin(__builtin_expect)) && !defined(__COVERITY__)
-#       define unlikely(cond) __builtin_expect(!!(cond), 0)
-#   else
-#       define unlikely(x) (!!(x))
-#   endif
-#endif /* unlikely */
-
-#ifndef __anonymous_struct_extension__
-#   if defined(__GNUC__)
-#       define __anonymous_struct_extension__ __extension__
-#   else
-#       define __anonymous_struct_extension__
-#   endif
-#endif /* __anonymous_struct_extension__ */
-
-#ifndef __Wpedantic_format_voidptr
-    static __inline __maybe_unused const void* MDBX_PURE_FUNCTION
-        __Wpedantic_format_voidptr(const void* ptr) {return ptr;}
-#   define __Wpedantic_format_voidptr(ARG) __Wpedantic_format_voidptr(ARG)
-#endif /* __Wpedantic_format_voidptr */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(MDBX_USE_VALGRIND)
-#   include <valgrind/memcheck.h>
-#   ifndef VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE
-        /* LY: available since Valgrind 3.10 */
-#       define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#       define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   endif
-#elif !defined(RUNNING_ON_VALGRIND)
-#   define VALGRIND_CREATE_MEMPOOL(h,r,z)
-#   define VALGRIND_DESTROY_MEMPOOL(h)
-#   define VALGRIND_MEMPOOL_TRIM(h,a,s)
-#   define VALGRIND_MEMPOOL_ALLOC(h,a,s)
-#   define VALGRIND_MEMPOOL_FREE(h,a)
-#   define VALGRIND_MEMPOOL_CHANGE(h,a,b,s)
-#   define VALGRIND_MAKE_MEM_NOACCESS(a,s)
-#   define VALGRIND_MAKE_MEM_DEFINED(a,s)
-#   define VALGRIND_MAKE_MEM_UNDEFINED(a,s)
-#   define VALGRIND_DISABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_ENABLE_ADDR_ERROR_REPORTING_IN_RANGE(a,s)
-#   define VALGRIND_CHECK_MEM_IS_ADDRESSABLE(a,s) (0)
-#   define VALGRIND_CHECK_MEM_IS_DEFINED(a,s) (0)
-#   define RUNNING_ON_VALGRIND (0)
-#endif /* MDBX_USE_VALGRIND */
-
-#ifdef __SANITIZE_ADDRESS__
-#   include <sanitizer/asan_interface.h>
-#elif !defined(ASAN_POISON_MEMORY_REGION)
-#   define ASAN_POISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#   define ASAN_UNPOISON_MEMORY_REGION(addr, size) \
-        ((void)(addr), (void)(size))
-#endif /* __SANITIZE_ADDRESS__ */
-
-/*----------------------------------------------------------------------------*/
-
-#ifndef ARRAY_LENGTH
-#   ifdef __cplusplus
-        template <typename T, size_t N>
-        char (&__ArraySizeHelper(T (&array)[N]))[N];
-#       define ARRAY_LENGTH(array) (sizeof(::__ArraySizeHelper(array)))
-#   else
-#       define ARRAY_LENGTH(array) (sizeof(array) / sizeof(array[0]))
-#   endif
-#endif /* ARRAY_LENGTH */
-
-#ifndef ARRAY_END
-#   define ARRAY_END(array) (&array[ARRAY_LENGTH(array)])
-#endif /* ARRAY_END */
-
-#ifndef STRINGIFY
-#   define STRINGIFY_HELPER(x) #x
-#   define STRINGIFY(x) STRINGIFY_HELPER(x)
-#endif /* STRINGIFY */
-
-#define CONCAT(a,b) a##b
-#define XCONCAT(a,b) CONCAT(a,b)
-
-#ifndef offsetof
-#   define offsetof(type, member)  __builtin_offsetof(type, member)
-#endif /* offsetof */
-
-#ifndef container_of
-#   define container_of(ptr, type, member) \
-        ((type *)((char *)(ptr) - offsetof(type, member)))
-#endif /* container_of */
-
-#define MDBX_TETRAD(a, b, c, d)                                                \
-  ((uint32_t)(a) << 24 | (uint32_t)(b) << 16 | (uint32_t)(c) << 8 | (d))
-
-#define MDBX_STRING_TETRAD(str) MDBX_TETRAD(str[0], str[1], str[2], str[3])
-
-#define FIXME "FIXME: " __FILE__ ", " STRINGIFY(__LINE__)
-
-#ifndef STATIC_ASSERT_MSG
-#   if defined(static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) static_assert(expr, msg)
-#   elif defined(_STATIC_ASSERT)
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif defined(_MSC_VER)
-#       include <crtdbg.h>
-#       define STATIC_ASSERT_MSG(expr, msg) _STATIC_ASSERT(expr)
-#   elif (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
-          || __has_feature(c_static_assert)
-#       define STATIC_ASSERT_MSG(expr, msg) _Static_assert(expr, msg)
-#   else
-#       define STATIC_ASSERT_MSG(expr, msg) switch (0) {case 0:case (expr):;}
-#   endif
-#endif /* STATIC_ASSERT */
-
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(expr) STATIC_ASSERT_MSG(expr, #expr)
-#endif
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__GNUC__) && !__GNUC_PREREQ(4,2)
-    /* Actually libmdbx was not tested with compilers older than GCC 4.2.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required GCC >= 4.2"
-#endif
-
-#if defined(__clang__) && !__CLANG_PREREQ(3,8)
-    /* Actually libmdbx was not tested with CLANG older than 3.8.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old compilers.
-     */
-#   warning "libmdbx required CLANG >= 3.8"
-#endif
-
-#if defined(__GLIBC__) && !__GLIBC_PREREQ(2,12)
-    /* Actually libmdbx was not tested with something older than glibc 2.12.
-     * But you could ignore this warning at your own risk.
-     * In such case please don't rise up an issues related ONLY to old systems.
-     */
-#   warning "libmdbx was only tested with GLIBC >= 2.12."
-#endif
-
-#ifdef __SANITIZE_THREAD__
-#   warning "libmdbx don't compatible with ThreadSanitizer, you will get a lot of false-positive issues."
-#endif /* __SANITIZE_THREAD__ */
-
-#if __has_warning("-Wnested-anon-types")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wnested-anon-types"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wnested-anon-types"
-#   else
-#      pragma warning disable "nested-anon-types"
-#   endif
-#endif /* -Wnested-anon-types */
-
-#if __has_warning("-Wconstant-logical-operand")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Wconstant-logical-operand"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Wconstant-logical-operand"
-#   else
-#      pragma warning disable "constant-logical-operand"
-#   endif
-#endif /* -Wconstant-logical-operand */
-
-#if defined(__LCC__) && (__LCC__ <= 121)
-    /* bug #2798 */
-#   pragma diag_suppress alignment_reduction_ignored
-#elif defined(__ICC)
-#   pragma warning(disable: 3453 1366)
-#elif __has_warning("-Walignment-reduction-ignored")
-#   if defined(__clang__)
-#       pragma clang diagnostic ignored "-Walignment-reduction-ignored"
-#   elif defined(__GNUC__)
-#       pragma GCC diagnostic ignored "-Walignment-reduction-ignored"
-#   else
-#       pragma warning disable "alignment-reduction-ignored"
-#   endif
-#endif /* -Walignment-reduction-ignored */
-
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
-
-/*
- * Copyright 2015-2021 Leonid Yuriev <leo@yuriev.ru>
- * and other libmdbx authors: please see AUTHORS file.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted only as authorized by the OpenLDAP
- * Public License.
- *
- * A copy of this license is available in the file LICENSE in the
- * top-level directory of the distribution or, alternatively, at
- * <http://www.OpenLDAP.org/license.html>.
- */
-
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#endif                          /* _MSC_VER (warnings) */
-
-#if defined(_WIN32) || defined(_WIN64)
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#if !defined(_NO_CRT_STDIO_INLINE) && MDBX_BUILD_SHARED_LIBRARY &&             \
-    !defined(MDBX_TOOLS) && MDBX_AVOID_CRT
-#define _NO_CRT_STDIO_INLINE
-#endif
-#elif !defined(_POSIX_C_SOURCE)
-#define _POSIX_C_SOURCE 200809L
-#endif /* Windows */
-
-/*----------------------------------------------------------------------------*/
-/* C99 includes */
-#include <inttypes.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-#include <assert.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-
-/* C11 stdalign.h */
-#if __has_include(<stdalign.h>)
-#include <stdalign.h>
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-#define alignas(N) _Alignas(N)
-#elif defined(_MSC_VER)
-#define alignas(N) __declspec(align(N))
-#elif __has_attribute(__aligned__) || defined(__GNUC__)
-#define alignas(N) __attribute__((__aligned__(N)))
-#else
-#error "FIXME: Required _alignas() or equivalent."
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Systems includes */
-
-#ifdef __APPLE__
-#include <TargetConditionals.h>
-#endif /* Apple OSX & iOS */
-
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) ||     \
-    defined(__BSD__) || defined(__bsdi__) || defined(__DragonFly__) ||         \
-    defined(__APPLE__) || defined(__MACH__)
-#include <sys/cdefs.h>
-#include <sys/mount.h>
-#include <sys/sysctl.h>
-#include <sys/types.h>
-#if defined(__FreeBSD__) || defined(__DragonFly__)
-#include <vm/vm_param.h>
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-#include <uvm/uvm_param.h>
-#else
-#define SYSCTL_LEGACY_NONCONST_MIB
-#endif
-#ifndef __MACH__
-#include <sys/vmmeter.h>
-#endif
-#else
-#include <malloc.h>
-#if !(defined(__sun) || defined(__SVR4) || defined(__svr4__) ||                \
-      defined(_WIN32) || defined(_WIN64))
-#include <mntent.h>
-#endif /* !Solaris */
-#endif /* !xBSD */
-
-#if defined(__FreeBSD__) || __has_include(<malloc_np.h>)
-#include <malloc_np.h>
-#endif
-
-#if defined(__APPLE__) || defined(__MACH__) || __has_include(<malloc/malloc.h>)
-#include <malloc/malloc.h>
-#endif /* MacOS */
-
-#if defined(__MACH__)
-#include <mach/host_info.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-#include <uuid/uuid.h>
-#undef P_DIRTY
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-#include <linux/sysctl.h>
-#include <sched.h>
-#include <sys/sendfile.h>
-#include <sys/statfs.h>
-#endif /* Linux */
-
-#ifndef _XOPEN_SOURCE
-#define _XOPEN_SOURCE 0
-#endif
-
-#ifndef _XOPEN_SOURCE_EXTENDED
-#define _XOPEN_SOURCE_EXTENDED 0
-#else
-#include <utmpx.h>
-#endif /* _XOPEN_SOURCE_EXTENDED */
-
-#if defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#include <kstat.h>
-#include <sys/mnttab.h>
-/* On Solaris, it's easier to add a missing prototype rather than find a
- * combination of #defines that break nothing. */
-__extern_C key_t ftok(const char *, int);
-#endif /* SunOS/Solaris */
-
-#if defined(_WIN32) || defined(_WIN64)
-#ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
-#endif
-#include <excpt.h>
-#include <tlhelp32.h>
-#include <windows.h>
-#include <winnt.h>
-#include <winternl.h>
-#define HAVE_SYS_STAT_H
-#define HAVE_SYS_TYPES_H
-typedef HANDLE mdbx_thread_t;
-typedef unsigned mdbx_thread_key_t;
-#define MDBX_OSAL_SECTION HANDLE
-#define MAP_FAILED NULL
-#define HIGH_DWORD(v) ((DWORD)((sizeof(v) > 4) ? ((uint64_t)(v) >> 32) : 0))
-#define THREAD_CALL WINAPI
-#define THREAD_RESULT DWORD
-typedef struct {
-  HANDLE mutex;
-  HANDLE event[2];
-} mdbx_condpair_t;
-typedef CRITICAL_SECTION mdbx_fastmutex_t;
-
-#if MDBX_AVOID_CRT
-#ifndef mdbx_malloc
-static inline void *mdbx_malloc(size_t bytes) {
-  return LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_malloc */
-
-#ifndef mdbx_calloc
-static inline void *mdbx_calloc(size_t nelem, size_t size) {
-  return LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, nelem * size);
-}
-#endif /* mdbx_calloc */
-
-#ifndef mdbx_realloc
-static inline void *mdbx_realloc(void *ptr, size_t bytes) {
-  return ptr ? LocalReAlloc(ptr, bytes, LMEM_MOVEABLE)
-             : LocalAlloc(LMEM_FIXED, bytes);
-}
-#endif /* mdbx_realloc */
-
-#ifndef mdbx_free
-#define mdbx_free LocalFree
-#endif /* mdbx_free */
-#else
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup _strdup
-#endif /* MDBX_AVOID_CRT */
-
-#ifndef snprintf
-#define snprintf _snprintf /* ntdll */
-#endif
-
-#ifndef vsnprintf
-#define vsnprintf _vsnprintf /* ntdll */
-#endif
-
-#else /*----------------------------------------------------------------------*/
-
-#include <pthread.h>
-#include <semaphore.h>
-#include <signal.h>
-#include <sys/file.h>
-#include <sys/ipc.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/statvfs.h>
-#include <sys/uio.h>
-#include <unistd.h>
-typedef pthread_t mdbx_thread_t;
-typedef pthread_key_t mdbx_thread_key_t;
-#define INVALID_HANDLE_VALUE (-1)
-#define THREAD_CALL
-#define THREAD_RESULT void *
-typedef struct {
-  pthread_mutex_t mutex;
-  pthread_cond_t cond[2];
-} mdbx_condpair_t;
-typedef pthread_mutex_t mdbx_fastmutex_t;
-#define mdbx_malloc malloc
-#define mdbx_calloc calloc
-#define mdbx_realloc realloc
-#define mdbx_free free
-#define mdbx_strdup strdup
-#endif /* Platform */
-
-#if __GLIBC_PREREQ(2, 12) || defined(__FreeBSD__) || defined(malloc_usable_size)
-/* malloc_usable_size() already provided */
-#elif defined(__APPLE__)
-#define malloc_usable_size(ptr) malloc_size(ptr)
-#elif defined(_MSC_VER) && !MDBX_AVOID_CRT
-#define malloc_usable_size(ptr) _msize(ptr)
-#endif /* malloc_usable_size */
-
-#ifdef __ANDROID_API__
-#include <android/log.h>
-#if __ANDROID_API__ >= 21
-#include <sys/sendfile.h>
-#endif
-#endif /* Android */
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(HAVE_SYS_STAT_H) || __has_include(<sys/stat.h>)
-#include <sys/stat.h>
-#endif
-#if defined(HAVE_SYS_TYPES_H) || __has_include(<sys/types.h>)
-#include <sys/types.h>
-#endif
-#if defined(HAVE_SYS_FILE_H) || __has_include(<sys/file.h>)
-#include <sys/file.h>
-#endif
-/* *INDENT-ON* */
-/* clang-format on */
-
-#ifndef SSIZE_MAX
-#define SSIZE_MAX INTPTR_MAX
-#endif
-
-#if !defined(MADV_DODUMP) && defined(MADV_CORE)
-#define MADV_DODUMP MADV_CORE
-#endif /* MADV_CORE -> MADV_DODUMP */
-
-#if !defined(MADV_DONTDUMP) && defined(MADV_NOCORE)
-#define MADV_DONTDUMP MADV_NOCORE
-#endif /* MADV_NOCORE -> MADV_DONTDUMP */
-
-#if defined(i386) || defined(__386) || defined(__i386) || defined(__i386__) || \
-    defined(i486) || defined(__i486) || defined(__i486__) ||                   \
-    defined(i586) | defined(__i586) || defined(__i586__) || defined(i686) ||   \
-    defined(__i686) || defined(__i686__) || defined(_M_IX86) ||                \
-    defined(_X86_) || defined(__THW_INTEL__) || defined(__I86__) ||            \
-    defined(__INTEL__) || defined(__x86_64) || defined(__x86_64__) ||          \
-    defined(__amd64__) || defined(__amd64) || defined(_M_X64) ||               \
-    defined(_M_AMD64) || defined(__IA32__) || defined(__INTEL__)
-#ifndef __ia32__
-/* LY: define neutral __ia32__ for x86 and x86-64 */
-#define __ia32__ 1
-#endif /* __ia32__ */
-#if !defined(__amd64__) && (defined(__x86_64) || defined(__x86_64__) ||        \
-                            defined(__amd64) || defined(_M_X64))
-/* LY: define trusty __amd64__ for all AMD64/x86-64 arch */
-#define __amd64__ 1
-#endif /* __amd64__ */
-#endif /* all x86 */
-
-#if (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
-#error                                                                         \
-    "Sanity checking failed: Two's complement, reasonably sized integer types"
-#endif
-
-#if UINTPTR_MAX > 0xffffFFFFul || ULONG_MAX > 0xffffFFFFul
-#define MDBX_WORDBITS 64
-#else
-#define MDBX_WORDBITS 32
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-/* Compiler's includes for builtins/intrinsics */
-
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
-#include <intrin.h>
-#elif __GNUC_PREREQ(4, 4) || defined(__clang__)
-#if defined(__ia32__) || defined(__e2k__)
-#include <x86intrin.h>
-#endif /* __ia32__ */
-#if defined(__ia32__)
-#include <cpuid.h>
-#endif /* __ia32__ */
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-#include <mbarrier.h>
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-#include <machine/sys/inline.h>
-#elif defined(__IBMC__) && defined(__powerpc)
-#include <atomic.h>
-#elif defined(_AIX)
-#include <builtins.h>
-#include <sys/atomic_op.h>
-#elif (defined(__osf__) && defined(__DECC)) || defined(__alpha)
-#include <c_asm.h>
-#include <machine/builtins.h>
-#elif defined(__MWERKS__)
-/* CodeWarrior - troubles ? */
-#pragma gcc_extensions
-#elif defined(__SNC__)
-/* Sony PS3 - troubles ? */
-#elif defined(__hppa__) || defined(__hppa)
-#include <machine/inline.h>
-#else
-#error Unsupported C compiler, please use GNU C 4.4 or newer
-#endif /* Compiler */
-
-/*----------------------------------------------------------------------------*/
-/* Byteorder */
-
-#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) ||           \
-    !defined(__ORDER_BIG_ENDIAN__)
-
-/* *INDENT-OFF* */
-/* clang-format off */
-#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID_API__) ||  \
-    defined(HAVE_ENDIAN_H) || __has_include(<endian.h>)
-#include <endian.h>
-#elif defined(__APPLE__) || defined(__MACH__) || defined(__OpenBSD__) ||       \
-    defined(HAVE_MACHINE_ENDIAN_H) || __has_include(<machine/endian.h>)
-#include <machine/endian.h>
-#elif defined(HAVE_SYS_ISA_DEFS_H) || __has_include(<sys/isa_defs.h>)
-#include <sys/isa_defs.h>
-#elif (defined(HAVE_SYS_TYPES_H) && defined(HAVE_SYS_ENDIAN_H)) ||             \
-    (__has_include(<sys/types.h>) && __has_include(<sys/endian.h>))
-#include <sys/endian.h>
-#include <sys/types.h>
-#elif defined(__bsdi__) || defined(__DragonFly__) || defined(__FreeBSD__) ||   \
-    defined(__NetBSD__) ||                              \
-    defined(HAVE_SYS_PARAM_H) || __has_include(<sys/param.h>)
-#include <sys/param.h>
-#endif /* OS */
-/* *INDENT-ON* */
-/* clang-format on */
-
-#if defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && defined(__BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ __LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ __BIG_ENDIAN
-#define __BYTE_ORDER__ __BYTE_ORDER
-#elif defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)
-#define __ORDER_LITTLE_ENDIAN__ _LITTLE_ENDIAN
-#define __ORDER_BIG_ENDIAN__ _BIG_ENDIAN
-#define __BYTE_ORDER__ _BYTE_ORDER
-#else
-#define __ORDER_LITTLE_ENDIAN__ 1234
-#define __ORDER_BIG_ENDIAN__ 4321
-
-#if defined(__LITTLE_ENDIAN__) ||                                              \
-    (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) ||                      \
-    defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) ||    \
-    defined(__MIPSEL__) || defined(_MIPSEL) || defined(__MIPSEL) ||            \
-    defined(_M_ARM) || defined(_M_ARM64) || defined(__e2k__) ||                \
-    defined(__elbrus_4c__) || defined(__elbrus_8c__) || defined(__bfin__) ||   \
-    defined(__BFIN__) || defined(__ia64__) || defined(_IA64) ||                \
-    defined(__IA64__) || defined(__ia64) || defined(_M_IA64) ||                \
-    defined(__itanium__) || defined(__ia32__) || defined(__CYGWIN__) ||        \
-    defined(_WIN64) || defined(_WIN32) || defined(__TOS_WIN__) ||              \
-    defined(__WINDOWS__)
-#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
-
-#elif defined(__BIG_ENDIAN__) ||                                               \
-    (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) ||                      \
-    defined(__ARMEB__) || defined(__THUMBEB__) || defined(__AARCH64EB__) ||    \
-    defined(__MIPSEB__) || defined(_MIPSEB) || defined(__MIPSEB) ||            \
-    defined(__m68k__) || defined(M68000) || defined(__hppa__) ||               \
-    defined(__hppa) || defined(__HPPA__) || defined(__sparc__) ||              \
-    defined(__sparc) || defined(__370__) || defined(__THW_370__) ||            \
-    defined(__s390__) || defined(__s390x__) || defined(__SYSC_ZARCH__)
-#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
-
-#else
-#error __BYTE_ORDER__ should be defined.
-#endif /* Arch */
-
-#endif
-#endif /* __BYTE_ORDER__ || __ORDER_LITTLE_ENDIAN__ || __ORDER_BIG_ENDIAN__ */
-
-/* Get the size of a memory page for the system.
- * This is the basic size that the platform's memory manager uses, and is
- * fundamental to the use of memory-mapped files. */
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline size_t
-mdbx_syspagesize(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  SYSTEM_INFO si;
-  GetSystemInfo(&si);
-  return si.dwPageSize;
-#else
-  return sysconf(_SC_PAGE_SIZE);
-#endif
-}
-
-typedef struct mdbx_mmap_param {
-  union {
-    void *address;
-    uint8_t *dxb;
-    struct MDBX_lockinfo *lck;
-  };
-  mdbx_filehandle_t fd;
-  size_t limit;   /* mapping length, but NOT a size of file nor DB */
-  size_t current; /* mapped region size, i.e. the size of file and DB */
-#if defined(_WIN32) || defined(_WIN64)
-  uint64_t filesize /* in-process cache of a file size. */;
-#endif
-#ifdef MDBX_OSAL_SECTION
-  MDBX_OSAL_SECTION section;
-#endif
-} mdbx_mmap_t;
-
-typedef union bin128 {
-  __anonymous_struct_extension__ struct { uint64_t x, y; };
-  __anonymous_struct_extension__ struct { uint32_t a, b, c, d; };
-} bin128_t;
-
-#if defined(_WIN32) || defined(_WIN64)
-typedef union MDBX_srwlock {
-  struct {
-    long volatile readerCount;
-    long volatile writerCount;
-  };
-  RTL_SRWLOCK native;
-} MDBX_srwlock;
-#endif /* Windows */
-
-#ifdef __cplusplus
-extern void mdbx_osal_jitter(bool tiny);
-#else
-
-/*----------------------------------------------------------------------------*/
-/* Atomics */
-
-#if defined(__cplusplus) && !defined(__STDC_NO_ATOMICS__) && (__has_include(<cstdatomic>) || __has_extension(cxx_atomic))
-#include <cstdatomic>
-#define MDBX_HAVE_C11ATOMICS
-#elif !defined(__cplusplus) &&                                                 \
-    (__STDC_VERSION__ >= 201112L || __has_extension(c_atomic)) &&              \
-    !defined(__STDC_NO_ATOMICS__) &&                                           \
-    (__GNUC_PREREQ(4, 9) || __CLANG_PREREQ(3, 8) ||                            \
-     !(defined(__GNUC__) || defined(__clang__)))
-#include <stdatomic.h>
-#define MDBX_HAVE_C11ATOMICS
-#elif defined(__GNUC__) || defined(__clang__)
-#elif defined(_MSC_VER)
-#pragma warning(disable : 4163) /* 'xyz': not available as an intrinsic */
-#pragma warning(disable : 4133) /* 'function': incompatible types - from       \
-                                   'size_t' to 'LONGLONG' */
-#pragma warning(disable : 4244) /* 'return': conversion from 'LONGLONG' to     \
-                                   'std::size_t', possible loss of data */
-#pragma warning(disable : 4267) /* 'function': conversion from 'size_t' to     \
-                                   'long', possible loss of data */
-#pragma intrinsic(_InterlockedExchangeAdd, _InterlockedCompareExchange)
-#pragma intrinsic(_InterlockedExchangeAdd64, _InterlockedCompareExchange64)
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-#else
-#error FIXME atomic-ops
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Memory/Compiler barriers, cache coherence */
-
-#if __has_include(<sys/cachectl.h>)
-#include <sys/cachectl.h>
-#elif defined(__mips) || defined(__mips__) || defined(__mips64) ||             \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS should have explicit cache control */
-#include <sys/cachectl.h>
-#endif
-
-static __maybe_unused __inline void mdbx_compiler_barrier(void) {
-#if defined(__clang__) || defined(__GNUC__)
-  __asm__ __volatile__("" ::: "memory");
-#elif defined(_MSC_VER)
-  _ReadWriteBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-  __memory_barrier();
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __compiler_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_sched_fence(/* LY: no-arg meaning 'all expect ALU', e.g. 0x3D3D */);
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __fence();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-static __maybe_unused __inline void mdbx_memory_barrier(void) {
-#ifdef MDBX_HAVE_C11ATOMICS
-  atomic_thread_fence(memory_order_seq_cst);
-#elif defined(__ATOMIC_SEQ_CST)
-#ifdef __clang__
-  __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
-#else
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-#endif
-#elif defined(__clang__) || defined(__GNUC__)
-  __sync_synchronize();
-#elif defined(_WIN32) || defined(_WIN64)
-  MemoryBarrier();
-#elif defined(__INTEL_COMPILER) /* LY: Intel Compiler may mimic GCC and MSC */
-#if defined(__ia32__)
-  _mm_mfence();
-#else
-  __mf();
-#endif
-#elif defined(__SUNPRO_C) || defined(__sun) || defined(sun)
-  __machine_rw_barrier();
-#elif (defined(_HPUX_SOURCE) || defined(__hpux) || defined(__HP_aCC)) &&       \
-    (defined(HP_IA64) || defined(__ia64))
-  _Asm_mf();
-#elif defined(_AIX) || defined(__ppc__) || defined(__powerpc__) ||             \
-    defined(__ppc64__) || defined(__powerpc64__)
-  __lwsync();
-#else
-#error "Could not guess the kind of compiler, please report to us."
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* libc compatibility stuff */
-
-#if (!defined(__GLIBC__) && __GLIBC_PREREQ(2, 1)) &&                           \
-    (defined(_GNU_SOURCE) || defined(_BSD_SOURCE))
-#define mdbx_asprintf asprintf
-#define mdbx_vasprintf vasprintf
-#else
-MDBX_INTERNAL_FUNC MDBX_PRINTF_ARGS(2, 3) int __maybe_unused
-    mdbx_asprintf(char **strp, const char *fmt, ...);
-MDBX_INTERNAL_FUNC int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* OS abstraction layer stuff */
-
-/* max bytes to write in one call */
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_WRITE UINT32_C(0x01000000)
-#else
-#define MAX_WRITE UINT32_C(0x3fff0000)
-#endif
-
-#if defined(__linux__) || defined(__gnu_linux__)
-MDBX_INTERNAL_VAR uint32_t mdbx_linux_kernel_version;
-MDBX_INTERNAL_VAR bool mdbx_RunningOnWSL1 /* Windows Subsystem 1 for Linux */;
-#endif /* Linux */
-
-#ifndef mdbx_strdup
-LIBMDBX_API char *mdbx_strdup(const char *str);
-#endif
-
-static __maybe_unused __inline int mdbx_get_errno(void) {
-#if defined(_WIN32) || defined(_WIN64)
-  DWORD rc = GetLastError();
-#else
-  int rc = errno;
-#endif
-  return rc;
-}
-
-#ifndef mdbx_memalign_alloc
-MDBX_INTERNAL_FUNC int mdbx_memalign_alloc(size_t alignment, size_t bytes,
-                                           void **result);
-#endif
-#ifndef mdbx_memalign_free
-MDBX_INTERNAL_FUNC void mdbx_memalign_free(void *ptr);
-#endif
-
-MDBX_INTERNAL_FUNC int mdbx_condpair_init(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_lock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_unlock(mdbx_condpair_t *condpair);
-MDBX_INTERNAL_FUNC int mdbx_condpair_signal(mdbx_condpair_t *condpair,
-                                            bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_wait(mdbx_condpair_t *condpair, bool part);
-MDBX_INTERNAL_FUNC int mdbx_condpair_destroy(mdbx_condpair_t *condpair);
-
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_init(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_acquire(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_release(mdbx_fastmutex_t *fastmutex);
-MDBX_INTERNAL_FUNC int mdbx_fastmutex_destroy(mdbx_fastmutex_t *fastmutex);
-
-MDBX_INTERNAL_FUNC int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov,
-                                    int iovcnt, uint64_t offset,
-                                    size_t expected_written);
-MDBX_INTERNAL_FUNC int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count,
-                                  uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf,
-                                   size_t count, uint64_t offset);
-MDBX_INTERNAL_FUNC int mdbx_write(mdbx_filehandle_t fd, const void *buf,
-                                  size_t count);
-
-MDBX_INTERNAL_FUNC int
-mdbx_thread_create(mdbx_thread_t *thread,
-                   THREAD_RESULT(THREAD_CALL *start_routine)(void *),
-                   void *arg);
-MDBX_INTERNAL_FUNC int mdbx_thread_join(mdbx_thread_t thread);
-
-enum mdbx_syncmode_bits {
-  MDBX_SYNC_NONE = 0,
-  MDBX_SYNC_DATA = 1,
-  MDBX_SYNC_SIZE = 2,
-  MDBX_SYNC_IODQ = 4
-};
-
-MDBX_INTERNAL_FUNC int mdbx_fsync(mdbx_filehandle_t fd,
-                                  const enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_ftruncate(mdbx_filehandle_t fd, uint64_t length);
-MDBX_INTERNAL_FUNC int mdbx_fseek(mdbx_filehandle_t fd, uint64_t pos);
-MDBX_INTERNAL_FUNC int mdbx_filesize(mdbx_filehandle_t fd, uint64_t *length);
-
-enum mdbx_openfile_purpose {
-  MDBX_OPEN_DXB_READ = 0,
-  MDBX_OPEN_DXB_LAZY = 1,
-  MDBX_OPEN_DXB_DSYNC = 2,
-  MDBX_OPEN_LCK = 3,
-  MDBX_OPEN_COPY = 4,
-  MDBX_OPEN_DELETE = 5
-};
-
-MDBX_INTERNAL_FUNC int mdbx_openfile(const enum mdbx_openfile_purpose purpose,
-                                     const MDBX_env *env, const char *pathname,
-                                     mdbx_filehandle_t *fd,
-                                     mdbx_mode_t unix_mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_closefile(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_removefile(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_removedirectory(const char *pathname);
-MDBX_INTERNAL_FUNC int mdbx_is_pipe(mdbx_filehandle_t fd);
-MDBX_INTERNAL_FUNC int mdbx_lockfile(mdbx_filehandle_t fd, bool wait);
-
-#define MMAP_OPTION_TRUNCATE 1
-#define MMAP_OPTION_SEMAPHORE 2
-MDBX_INTERNAL_FUNC int mdbx_mmap(const int flags, mdbx_mmap_t *map,
-                                 const size_t must, const size_t limit,
-                                 const unsigned options);
-MDBX_INTERNAL_FUNC int mdbx_munmap(mdbx_mmap_t *map);
-MDBX_INTERNAL_FUNC int mdbx_mresize(int flags, mdbx_mmap_t *map, size_t current,
-                                    size_t wanna, const bool may_move);
-#if defined(_WIN32) || defined(_WIN64)
-typedef struct {
-  unsigned limit, count;
-  HANDLE handles[31];
-} mdbx_handle_array_t;
-MDBX_INTERNAL_FUNC int
-mdbx_suspend_threads_before_remap(MDBX_env *env, mdbx_handle_array_t **array);
-MDBX_INTERNAL_FUNC int
-mdbx_resume_threads_after_remap(mdbx_handle_array_t *array);
-#endif /* Windows */
-MDBX_INTERNAL_FUNC int mdbx_msync(mdbx_mmap_t *map, size_t offset,
-                                  size_t length,
-                                  enum mdbx_syncmode_bits mode_bits);
-MDBX_INTERNAL_FUNC int mdbx_check_fs_rdonly(mdbx_filehandle_t handle,
-                                            const char *pathname, int err);
-
-static __maybe_unused __inline uint32_t mdbx_getpid(void) {
-  STATIC_ASSERT(sizeof(mdbx_pid_t) <= sizeof(uint32_t));
-#if defined(_WIN32) || defined(_WIN64)
-  return GetCurrentProcessId();
-#else
-  return getpid();
-#endif
-}
-
-static __maybe_unused __inline uintptr_t mdbx_thread_self(void) {
-  mdbx_tid_t thunk;
-  STATIC_ASSERT(sizeof(uintptr_t) >= sizeof(thunk));
-#if defined(_WIN32) || defined(_WIN64)
-  thunk = GetCurrentThreadId();
-#else
-  thunk = pthread_self();
-#endif
-  return (uintptr_t)thunk;
-}
-
-MDBX_INTERNAL_FUNC void __maybe_unused mdbx_osal_jitter(bool tiny);
-MDBX_INTERNAL_FUNC uint64_t mdbx_osal_monotime(void);
-MDBX_INTERNAL_FUNC uint64_t
-mdbx_osal_16dot16_to_monotime(uint32_t seconds_16dot16);
-MDBX_INTERNAL_FUNC uint32_t mdbx_osal_monotime_to_16dot16(uint64_t monotime);
-
-MDBX_INTERNAL_FUNC bin128_t mdbx_osal_bootid(void);
-/*----------------------------------------------------------------------------*/
-/* lck stuff */
-
-/// \brief Initialization of synchronization primitives linked with MDBX_env
-///   instance both in LCK-file and within the current process.
-/// \param
-///   global_uniqueness_flag = true - denotes that there are no other processes
-///     working with DB and LCK-file. Thus the function MUST initialize
-///     shared synchronization objects in memory-mapped LCK-file.
-///   global_uniqueness_flag = false - denotes that at least one process is
-///     already working with DB and LCK-file, including the case when DB
-///     has already been opened in the current process. Thus the function
-///     MUST NOT initialize shared synchronization objects in memory-mapped
-///     LCK-file that are already in use.
-/// \return Error code or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_init(MDBX_env *env,
-                                     MDBX_env *inprocess_neighbor,
-                                     int global_uniqueness_flag);
-
-/// \brief Disconnects from shared interprocess objects and destructs
-///   synchronization objects linked with MDBX_env instance
-///   within the current process.
-/// \param
-///   inprocess_neighbor = NULL - if the current process does not have other
-///     instances of MDBX_env linked with the DB being closed.
-///     Thus the function MUST check for other processes working with DB or
-///     LCK-file, and keep or destroy shared synchronization objects in
-///     memory-mapped LCK-file depending on the result.
-///   inprocess_neighbor = not-NULL - pointer to another instance of MDBX_env
-///     (anyone of there is several) working with DB or LCK-file within the
-///     current process. Thus the function MUST NOT try to acquire exclusive
-///     lock and/or try to destruct shared synchronization objects linked with
-///     DB or LCK-file. Moreover, the implementation MUST ensure correct work
-///     of other instances of MDBX_env within the current process, e.g.
-///     restore POSIX-fcntl locks after the closing of file descriptors.
-/// \return Error code (MDBX_PANIC) or zero on success.
-MDBX_INTERNAL_FUNC int mdbx_lck_destroy(MDBX_env *env,
-                                        MDBX_env *inprocess_neighbor);
-
-/// \brief Connects to shared interprocess locking objects and tries to acquire
-///   the maximum lock level (shared if exclusive is not available)
-///   Depending on implementation or/and platform (Windows) this function may
-///   acquire the non-OS super-level lock (e.g. for shared synchronization
-///   objects initialization), which will be downgraded to OS-exclusive or
-///   shared via explicit calling of mdbx_lck_downgrade().
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if an exclusive lock was acquired and thus
-///     the current process is the first and only after the last use of DB.
-///   MDBX_RESULT_FALSE (0) - if a shared lock was acquired and thus
-///     DB has already been opened and now is used by other processes.
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_lck_seize(MDBX_env *env);
-
-/// \brief Downgrades the level of initially acquired lock to
-///   operational level specified by argument. The reson for such downgrade:
-///    - unblocking of other processes that are waiting for access, i.e.
-///      if (env->me_flags & MDBX_EXCLUSIVE) != 0, then other processes
-///      should be made aware that access is unavailable rather than
-///      wait for it.
-///    - freeing locks that interfere file operation (especially for Windows)
-///   (env->me_flags & MDBX_EXCLUSIVE) == 0 - downgrade to shared lock.
-///   (env->me_flags & MDBX_EXCLUSIVE) != 0 - downgrade to exclusive
-///   operational lock.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_lck_downgrade(MDBX_env *env);
-
-/// \brief Locks LCK-file or/and table of readers for (de)registering.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rdt_lock(MDBX_env *env);
-
-/// \brief Unlocks LCK-file or/and table of readers after (de)registering.
-MDBX_INTERNAL_FUNC void mdbx_rdt_unlock(MDBX_env *env);
-
-/// \brief Acquires lock for DB change (on writing transaction start)
-///   Reading transactions will not be blocked.
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-/// \return Error code or zero on success
-LIBMDBX_API int mdbx_txn_lock(MDBX_env *env, bool dont_wait);
-
-/// \brief Releases lock once DB changes is made (after writing transaction
-///   has finished).
-///   Declared as LIBMDBX_API because it is used in mdbx_chk.
-LIBMDBX_API void mdbx_txn_unlock(MDBX_env *env);
-
-/// \brief Sets alive-flag of reader presence (indicative lock) for PID of
-///   the current process. The function does no more than needed for
-///   the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_set(MDBX_env *env);
-
-/// \brief Resets alive-flag of reader presence (indicative lock)
-///   for PID of the current process. The function does no more than needed
-///   for the correct working of mdbx_rpid_check() in other processes.
-/// \return Error code or zero on success
-MDBX_INTERNAL_FUNC int mdbx_rpid_clear(MDBX_env *env);
-
-/// \brief Checks for reading process status with the given pid with help of
-///   alive-flag of presence (indicative lock) or using another way.
-/// \return
-///   MDBX_RESULT_TRUE (-1) - if the reader process with the given PID is alive
-///     and working with DB (indicative lock is present).
-///   MDBX_RESULT_FALSE (0) - if the reader process with the given PID is absent
-///     or not working with DB (indicative lock is not present).
-///   Otherwise (not 0 and not -1) - error code.
-MDBX_INTERNAL_FUNC int mdbx_rpid_check(MDBX_env *env, uint32_t pid);
-
-#if defined(_WIN32) || defined(_WIN64)
-
-typedef void(WINAPI *MDBX_srwlock_function)(MDBX_srwlock *);
-MDBX_INTERNAL_VAR MDBX_srwlock_function mdbx_srwlock_Init,
-    mdbx_srwlock_AcquireShared, mdbx_srwlock_ReleaseShared,
-    mdbx_srwlock_AcquireExclusive, mdbx_srwlock_ReleaseExclusive;
-
-typedef BOOL(WINAPI *MDBX_GetFileInformationByHandleEx)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_GetFileInformationByHandleEx
-    mdbx_GetFileInformationByHandleEx;
-
-typedef BOOL(WINAPI *MDBX_GetVolumeInformationByHandleW)(
-    _In_ HANDLE hFile, _Out_opt_ LPWSTR lpVolumeNameBuffer,
-    _In_ DWORD nVolumeNameSize, _Out_opt_ LPDWORD lpVolumeSerialNumber,
-    _Out_opt_ LPDWORD lpMaximumComponentLength,
-    _Out_opt_ LPDWORD lpFileSystemFlags,
-    _Out_opt_ LPWSTR lpFileSystemNameBuffer, _In_ DWORD nFileSystemNameSize);
-MDBX_INTERNAL_VAR MDBX_GetVolumeInformationByHandleW
-    mdbx_GetVolumeInformationByHandleW;
-
-typedef DWORD(WINAPI *MDBX_GetFinalPathNameByHandleW)(_In_ HANDLE hFile,
-                                                      _Out_ LPWSTR lpszFilePath,
-                                                      _In_ DWORD cchFilePath,
-                                                      _In_ DWORD dwFlags);
-MDBX_INTERNAL_VAR MDBX_GetFinalPathNameByHandleW mdbx_GetFinalPathNameByHandleW;
-
-typedef BOOL(WINAPI *MDBX_SetFileInformationByHandle)(
-    _In_ HANDLE hFile, _In_ FILE_INFO_BY_HANDLE_CLASS FileInformationClass,
-    _Out_ LPVOID lpFileInformation, _In_ DWORD dwBufferSize);
-MDBX_INTERNAL_VAR MDBX_SetFileInformationByHandle
-    mdbx_SetFileInformationByHandle;
-
-typedef NTSTATUS(NTAPI *MDBX_NtFsControlFile)(
-    IN HANDLE FileHandle, IN OUT HANDLE Event,
-    IN OUT PVOID /* PIO_APC_ROUTINE */ ApcRoutine, IN OUT PVOID ApcContext,
-    OUT PIO_STATUS_BLOCK IoStatusBlock, IN ULONG FsControlCode,
-    IN OUT PVOID InputBuffer, IN ULONG InputBufferLength,
-    OUT OPTIONAL PVOID OutputBuffer, IN ULONG OutputBufferLength);
-MDBX_INTERNAL_VAR MDBX_NtFsControlFile mdbx_NtFsControlFile;
-
-typedef uint64_t(WINAPI *MDBX_GetTickCount64)(void);
-MDBX_INTERNAL_VAR MDBX_GetTickCount64 mdbx_GetTickCount64;
-
-#if !defined(_WIN32_WINNT_WIN8) || _WIN32_WINNT < _WIN32_WINNT_WIN8
-typedef struct _WIN32_MEMORY_RANGE_ENTRY {
-  PVOID VirtualAddress;
-  SIZE_T NumberOfBytes;
-} WIN32_MEMORY_RANGE_ENTRY, *PWIN32_MEMORY_RANGE_ENTRY;
-#endif /* Windows 8.x */
-
-typedef BOOL(WINAPI *MDBX_PrefetchVirtualMemory)(
-    HANDLE hProcess, ULONG_PTR NumberOfEntries,
-    PWIN32_MEMORY_RANGE_ENTRY VirtualAddresses, ULONG Flags);
-MDBX_INTERNAL_VAR MDBX_PrefetchVirtualMemory mdbx_PrefetchVirtualMemory;
-
-#if 0 /* LY: unused for now */
-#if !defined(_WIN32_WINNT_WIN81) || _WIN32_WINNT < _WIN32_WINNT_WIN81
-typedef enum OFFER_PRIORITY {
-  VmOfferPriorityVeryLow = 1,
-  VmOfferPriorityLow,
-  VmOfferPriorityBelowNormal,
-  VmOfferPriorityNormal
-} OFFER_PRIORITY;
-#endif /* Windows 8.1 */
-
-typedef DWORD(WINAPI *MDBX_DiscardVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_DiscardVirtualMemory mdbx_DiscardVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_ReclaimVirtualMemory)(PVOID VirtualAddress,
-                                                 SIZE_T Size);
-MDBX_INTERNAL_VAR MDBX_ReclaimVirtualMemory mdbx_ReclaimVirtualMemory;
-
-typedef DWORD(WINAPI *MDBX_OfferVirtualMemory(
-  PVOID          VirtualAddress,
-  SIZE_T         Size,
-  OFFER_PRIORITY Priority
-);
-MDBX_INTERNAL_VAR MDBX_OfferVirtualMemory mdbx_OfferVirtualMemory;
-#endif /* unused for now */
-
-typedef enum _SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 } SECTION_INHERIT;
-
-typedef NTSTATUS(NTAPI *MDBX_NtExtendSection)(IN HANDLE SectionHandle,
-                                              IN PLARGE_INTEGER NewSectionSize);
-MDBX_INTERNAL_VAR MDBX_NtExtendSection mdbx_NtExtendSection;
-
-static __inline bool mdbx_RunningUnderWine(void) {
-  return !mdbx_NtExtendSection;
-}
-
-typedef LSTATUS(WINAPI *MDBX_RegGetValueA)(HKEY hkey, LPCSTR lpSubKey,
-                                           LPCSTR lpValue, DWORD dwFlags,
-                                           LPDWORD pdwType, PVOID pvData,
-                                           LPDWORD pcbData);
-MDBX_INTERNAL_VAR MDBX_RegGetValueA mdbx_RegGetValueA;
-
-#endif /* Windows */
-
-#endif /* !__cplusplus */
-
-/*----------------------------------------------------------------------------*/
-
-#if defined(_MSC_VER) && _MSC_VER >= 1900
-/* LY: MSVC 2015/2017/2019 has buggy/inconsistent PRIuPTR/PRIxPTR macros
- * for internal format-args checker. */
-#undef PRIuPTR
-#undef PRIiPTR
-#undef PRIdPTR
-#undef PRIxPTR
-#define PRIuPTR "Iu"
-#define PRIiPTR "Ii"
-#define PRIdPTR "Id"
-#define PRIxPTR "Ix"
-#define PRIuSIZE "zu"
-#define PRIiSIZE "zi"
-#define PRIdSIZE "zd"
-#define PRIxSIZE "zx"
-#endif /* fix PRI*PTR for _MSC_VER */
-
-#ifndef PRIuSIZE
-#define PRIuSIZE PRIuPTR
-#define PRIiSIZE PRIiPTR
-#define PRIdSIZE PRIdPTR
-#define PRIxSIZE PRIxPTR
-#endif /* PRI*SIZE macros for MSVC */
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-
-#define mdbx_sourcery_anchor XCONCAT(mdbx_sourcery_, MDBX_BUILD_SOURCERY)
-#if defined(MDBX_TOOLS)
-extern LIBMDBX_API const char *const mdbx_sourcery_anchor;
-#endif
-
-/*******************************************************************************
- *******************************************************************************
- *******************************************************************************
- *
- *
- *         ####   #####    #####     #     ####   #    #   ####
- *        #    #  #    #     #       #    #    #  ##   #  #
- *        #    #  #    #     #       #    #    #  # #  #   ####
- *        #    #  #####      #       #    #    #  #  # #       #
- *        #    #  #          #       #    #    #  #   ##  #    #
- *         ####   #          #       #     ####   #    #   ####
- *
- *
- */
-
-/** \defgroup build_option Build options
- * The libmdbx build options.
- @{ */
-
-#ifdef DOXYGEN
-/* !!! Actually this is a fake definitions     !!!
- * !!! for documentation generation by Doxygen !!! */
-
-/** Controls enabling of debugging features.
- *
- *  - `MDBX_DEBUG = 0` (by default) Disables any debugging features at all,
- *                     including logging and assertion controls.
- *                     Logging level and corresponding debug flags changing
- *                     by \ref mdbx_setup_debug() will not have effect.
- *  - `MDBX_DEBUG > 0` Enables code for the debugging features (logging,
- *                     assertions checking and internal audit).
- *                     Simultaneously sets the default logging level
- *                     to the `MDBX_DEBUG` value.
- *                     Also enables \ref MDBX_DBG_AUDIT if `MDBX_DEBUG >= 2`.
- *
- * \ingroup build_option */
-#define MDBX_DEBUG 0...7
-
-/** Disables using of GNU libc extensions. */
-#define MDBX_DISABLE_GNU_SOURCE 0 or 1
-
-#endif /* DOXYGEN */
-
-/** Using fcntl(F_FULLFSYNC) with 5-10 times slowdown */
-#define MDBX_OSX_WANNA_DURABILITY 0
-/** Using fsync() with chance of data lost on power failure */
-#define MDBX_OSX_WANNA_SPEED 1
-
-#ifndef MDBX_OSX_SPEED_INSTEADOF_DURABILITY
-/** Choices \ref MDBX_OSX_WANNA_DURABILITY or \ref MDBX_OSX_WANNA_SPEED
- * for OSX & iOS */
-#define MDBX_OSX_SPEED_INSTEADOF_DURABILITY MDBX_OSX_WANNA_DURABILITY
-#endif /* MDBX_OSX_SPEED_INSTEADOF_DURABILITY */
-
-/** Controls checking PID against reuse DB environment after the fork() */
-#ifndef MDBX_ENV_CHECKPID
-#if defined(MADV_DONTFORK) || defined(_WIN32) || defined(_WIN64)
-/* PID check could be omitted:
- *  - on Linux when madvise(MADV_DONTFORK) is available, i.e. after the fork()
- *    mapped pages will not be available for child process.
- *  - in Windows where fork() not available. */
-#define MDBX_ENV_CHECKPID 0
-#else
-#define MDBX_ENV_CHECKPID 1
-#endif
-#define MDBX_ENV_CHECKPID_CONFIG "AUTO=" STRINGIFY(MDBX_ENV_CHECKPID)
-#else
-#define MDBX_ENV_CHECKPID_CONFIG STRINGIFY(MDBX_ENV_CHECKPID)
-#endif /* MDBX_ENV_CHECKPID */
-
-/** Controls checking transaction owner thread against misuse transactions from
- * other threads. */
-#ifndef MDBX_TXN_CHECKOWNER
-#define MDBX_TXN_CHECKOWNER 1
-#define MDBX_TXN_CHECKOWNER_CONFIG "AUTO=" STRINGIFY(MDBX_TXN_CHECKOWNER)
-#else
-#define MDBX_TXN_CHECKOWNER_CONFIG STRINGIFY(MDBX_TXN_CHECKOWNER)
-#endif /* MDBX_TXN_CHECKOWNER */
-
-/** Does a system have battery-backed Real-Time Clock or just a fake. */
-#ifndef MDBX_TRUST_RTC
-#if defined(__linux__) || defined(__gnu_linux__) || defined(__NetBSD__) ||     \
-    defined(__OpenBSD__)
-#define MDBX_TRUST_RTC 0 /* a lot of embedded systems have a fake RTC */
-#else
-#define MDBX_TRUST_RTC 1
-#endif
-#define MDBX_TRUST_RTC_CONFIG "AUTO=" STRINGIFY(MDBX_TRUST_RTC)
-#else
-#define MDBX_TRUST_RTC_CONFIG STRINGIFY(MDBX_TRUST_RTC)
-#endif /* MDBX_TRUST_RTC */
-
-/** Controls online database auto-compactification during write-transactions. */
-#ifndef MDBX_ENABLE_REFUND
-#define MDBX_ENABLE_REFUND 1
-#endif
-#if !(MDBX_ENABLE_REFUND == 0 || MDBX_ENABLE_REFUND == 1)
-#error MDBX_ENABLE_REFUND must be defined as 0 or 1
-#endif /* MDBX_ENABLE_REFUND */
-
-/** Controls sort order of internal page number lists.
- * The database format depend on this option and libmdbx builded with different
- * option value are incompatible. */
-#ifndef MDBX_PNL_ASCENDING
-#define MDBX_PNL_ASCENDING 0
-#endif
-#if !(MDBX_PNL_ASCENDING == 0 || MDBX_PNL_ASCENDING == 1)
-#error MDBX_PNL_ASCENDING must be defined as 0 or 1
-#endif /* MDBX_PNL_ASCENDING */
-
-//------------------------------------------------------------------------------
-
-/** Win32 File Locking API for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_WIN32FILES -1
-
-/** SystemV IPC semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_SYSV 5
-
-/** POSIX-1 Shared anonymous semaphores for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX1988 1988
-
-/** POSIX-2001 Shared Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2001 2001
-
-/** POSIX-2008 Robust Mutexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_POSIX2008 2008
-
-/** BeOS Benaphores, aka Futexes for \ref MDBX_LOCKING */
-#define MDBX_LOCKING_BENAPHORE 1995
-
-/** Advanced: Choices the locking implementation (autodetection by default). */
-#if defined(_WIN32) || defined(_WIN64)
-#define MDBX_LOCKING MDBX_LOCKING_WIN32FILES
-#else
-#ifndef MDBX_LOCKING
-#if defined(_POSIX_THREAD_PROCESS_SHARED) &&                                   \
-    _POSIX_THREAD_PROCESS_SHARED >= 200112L && !defined(__FreeBSD__)
-
-/* Some platforms define the EOWNERDEAD error code even though they
- * don't support Robust Mutexes. If doubt compile with -MDBX_LOCKING=2001. */
-#if defined(EOWNERDEAD) && _POSIX_THREAD_PROCESS_SHARED >= 200809L &&          \
-    ((defined(_POSIX_THREAD_ROBUST_PRIO_INHERIT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_INHERIT > 0) ||                                \
-     (defined(_POSIX_THREAD_ROBUST_PRIO_PROTECT) &&                            \
-      _POSIX_THREAD_ROBUST_PRIO_PROTECT > 0) ||                                \
-     defined(PTHREAD_MUTEX_ROBUST) || defined(PTHREAD_MUTEX_ROBUST_NP)) &&     \
-    (!defined(__GLIBC__) ||                                                    \
-     __GLIBC_PREREQ(2, 10) /* troubles with Robust mutexes before 2.10 */)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2008
-#else
-#define MDBX_LOCKING MDBX_LOCKING_POSIX2001
-#endif
-#elif defined(__sun) || defined(__SVR4) || defined(__svr4__)
-#define MDBX_LOCKING MDBX_LOCKING_POSIX1988
-#else
-#define MDBX_LOCKING MDBX_LOCKING_SYSV
-#endif
-#define MDBX_LOCKING_CONFIG "AUTO=" STRINGIFY(MDBX_LOCKING)
-#else
-#define MDBX_LOCKING_CONFIG STRINGIFY(MDBX_LOCKING)
-#endif /* MDBX_LOCKING */
-#endif /* !Windows */
-
-/** Advanced: Using POSIX OFD-locks (autodetection by default). */
-#ifndef MDBX_USE_OFDLOCKS
-#if defined(F_OFD_SETLK) && defined(F_OFD_SETLKW) && defined(F_OFD_GETLK) &&   \
-    !defined(MDBX_SAFE4QEMU) &&                                                \
-    !defined(__sun) /* OFD-lock are broken on Solaris */
-#define MDBX_USE_OFDLOCKS 1
-#else
-#define MDBX_USE_OFDLOCKS 0
-#endif
-#define MDBX_USE_OFDLOCKS_CONFIG "AUTO=" STRINGIFY(MDBX_USE_OFDLOCKS)
-#else
-#define MDBX_USE_OFDLOCKS_CONFIG STRINGIFY(MDBX_USE_OFDLOCKS)
-#endif /* MDBX_USE_OFDLOCKS */
-
-/** Advanced: Using sendfile() syscall (autodetection by default). */
-#ifndef MDBX_USE_SENDFILE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     !defined(__ANDROID_API__)) ||                                             \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 21)
-#define MDBX_USE_SENDFILE 1
-#else
-#define MDBX_USE_SENDFILE 0
-#endif
-#endif /* MDBX_USE_SENDFILE */
-
-/** Advanced: Using copy_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_COPYFILERANGE
-#if __GLIBC_PREREQ(2, 27) && defined(_GNU_SOURCE)
-#define MDBX_USE_COPYFILERANGE 1
-#else
-#define MDBX_USE_COPYFILERANGE 0
-#endif
-#endif /* MDBX_USE_COPYFILERANGE */
-
-/** Advanced: Using sync_file_range() syscall (autodetection by default). */
-#ifndef MDBX_USE_SYNCFILERANGE
-#if ((defined(__linux__) || defined(__gnu_linux__)) &&                         \
-     defined(SYNC_FILE_RANGE_WRITE) && !defined(__ANDROID_API__)) ||           \
-    (defined(__ANDROID_API__) && __ANDROID_API__ >= 26)
-#define MDBX_USE_SYNCFILERANGE 1
-#else
-#define MDBX_USE_SYNCFILERANGE 0
-#endif
-#endif /* MDBX_USE_SYNCFILERANGE */
-
-//------------------------------------------------------------------------------
-
-#ifndef MDBX_CPU_WRITEBACK_INCOHERENT
-#if defined(__ia32__) || defined(__e2k__) || defined(__hppa) ||                \
-    defined(__hppa__) || defined(DOXYGEN)
-#define MDBX_CPU_WRITEBACK_INCOHERENT 0
-#else
-#define MDBX_CPU_WRITEBACK_INCOHERENT 1
-#endif
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-#ifndef MDBX_MMAP_INCOHERENT_FILE_WRITE
-#ifdef __OpenBSD__
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 1
-#else
-#define MDBX_MMAP_INCOHERENT_FILE_WRITE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#ifndef MDBX_MMAP_INCOHERENT_CPU_CACHE
-#if defined(__mips) || defined(__mips__) || defined(__mips64) ||               \
-    defined(__mips64__) || defined(_M_MRX000) || defined(_MIPS_) ||            \
-    defined(__MWERKS__) || defined(__sgi)
-/* MIPS has cache coherency issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 1
-#else
-/* LY: assume no relevant mmap/dcache issues. */
-#define MDBX_MMAP_INCOHERENT_CPU_CACHE 0
-#endif
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#ifndef MDBX_64BIT_ATOMIC
-#if MDBX_WORDBITS >= 64 || defined(DOXYGEN)
-#define MDBX_64BIT_ATOMIC 1
-#else
-#define MDBX_64BIT_ATOMIC 0
-#endif
-#define MDBX_64BIT_ATOMIC_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_ATOMIC)
-#else
-#define MDBX_64BIT_ATOMIC_CONFIG STRINGIFY(MDBX_64BIT_ATOMIC)
-#endif /* MDBX_64BIT_ATOMIC */
-
-#ifndef MDBX_64BIT_CAS
-#if defined(ATOMIC_LLONG_LOCK_FREE)
-#if ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__GCC_ATOMIC_LLONG_LOCK_FREE)
-#if __GCC_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(__CLANG_ATOMIC_LLONG_LOCK_FREE)
-#if __CLANG_ATOMIC_LLONG_LOCK_FREE > 1
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS 0
-#endif
-#elif defined(_MSC_VER) || defined(__APPLE__) || defined(DOXYGEN)
-#define MDBX_64BIT_CAS 1
-#else
-#define MDBX_64BIT_CAS MDBX_64BIT_ATOMIC
-#endif
-#define MDBX_64BIT_CAS_CONFIG "AUTO=" STRINGIFY(MDBX_64BIT_CAS)
-#else
-#define MDBX_64BIT_CAS_CONFIG STRINGIFY(MDBX_64BIT_CAS)
-#endif /* MDBX_64BIT_CAS */
-
-#if !defined(MDBX_UNALIGNED_OK)
-#if defined(_MSC_VER)
-#define MDBX_UNALIGNED_OK 1 /* avoid MSVC misoptimization */
-#elif __CLANG_PREREQ(5, 0) || __GNUC_PREREQ(5, 0)
-#define MDBX_UNALIGNED_OK 0 /* expecting optimization is well done */
-#elif (defined(__ia32__) || defined(__ARM_FEATURE_UNALIGNED)) &&               \
-    !defined(__ALIGNED__)
-#define MDBX_UNALIGNED_OK 1
-#else
-#define MDBX_UNALIGNED_OK 0
-#endif
-#endif /* MDBX_UNALIGNED_OK */
-
-#ifndef MDBX_CACHELINE_SIZE
-#if defined(SYSTEM_CACHE_ALIGNMENT_SIZE)
-#define MDBX_CACHELINE_SIZE SYSTEM_CACHE_ALIGNMENT_SIZE
-#elif defined(__ia64__) || defined(__ia64) || defined(_M_IA64)
-#define MDBX_CACHELINE_SIZE 128
-#else
-#define MDBX_CACHELINE_SIZE 64
-#endif
-#endif /* MDBX_CACHELINE_SIZE */
-
-/** @} end of build options */
-/*******************************************************************************
- *******************************************************************************
- ******************************************************************************/
-
-/*----------------------------------------------------------------------------*/
-/* Basic constants and types */
-
-typedef union {
-  volatile uint32_t weak;
-#ifdef MDBX_HAVE_C11ATOMICS
-  volatile _Atomic uint32_t c11a;
-#endif /* MDBX_HAVE_C11ATOMICS */
-} MDBX_atomic_uint32_t;
-
-typedef union {
-  volatile uint64_t weak;
-#if defined(MDBX_HAVE_C11ATOMICS) && (MDBX_64BIT_CAS || MDBX_64BIT_ATOMIC)
-  volatile _Atomic uint64_t c11a;
-#endif
-#if !defined(MDBX_HAVE_C11ATOMICS) || !MDBX_64BIT_CAS || !MDBX_64BIT_ATOMIC
-  __anonymous_struct_extension__ struct {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    MDBX_atomic_uint32_t low, high;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-    MDBX_atomic_uint32_t high, low;
-#else
-#error "FIXME: Unsupported byte order"
-#endif /* __BYTE_ORDER__ */
-  };
-#endif
-} MDBX_atomic_uint64_t;
-
-/* The minimum number of keys required in a database page.
- * Setting this to a larger value will place a smaller bound on the
- * maximum size of a data item. Data items larger than this size will
- * be pushed into overflow pages instead of being stored directly in
- * the B-tree node. This value used to default to 4. With a page size
- * of 4096 bytes that meant that any item larger than 1024 bytes would
- * go into an overflow page. That also meant that on average 2-3KB of
- * each overflow page was wasted space. The value cannot be lower than
- * 2 because then there would no longer be a tree structure. With this
- * value, items larger than 2KB will go into overflow pages, and on
- * average only 1KB will be wasted. */
-#define MDBX_MINKEYS 2
-
-/* A stamp that identifies a file as an MDBX file.
- * There's nothing special about this value other than that it is easily
- * recognizable, and it will reflect any byte order mismatches. */
-#define MDBX_MAGIC UINT64_C(/* 56-bit prime */ 0x59659DBDEF4C11)
-
-/* The version number for a database's datafile format. */
-#define MDBX_DATA_VERSION 2
-/* The version number for a database's lockfile format. */
-#define MDBX_LOCK_VERSION 3
-
-/* handle for the DB used to track free pages. */
-#define FREE_DBI 0
-/* handle for the default DB. */
-#define MAIN_DBI 1
-/* Number of DBs in metapage (free and main) - also hardcoded elsewhere */
-#define CORE_DBS 2
-
-/* Number of meta pages - also hardcoded elsewhere */
-#define NUM_METAS 3
-
-/* A page number in the database.
- *
- * MDBX uses 32 bit for page numbers. This limits database
- * size up to 2^44 bytes, in case of 4K pages. */
-typedef uint32_t pgno_t;
-typedef MDBX_atomic_uint32_t atomic_pgno_t;
-#define PRIaPGNO PRIu32
-#define MAX_PAGENO UINT32_C(0x7FFFffff)
-#define MIN_PAGENO NUM_METAS
-
-#define SAFE64_INVALID_THRESHOLD UINT64_C(0xffffFFFF00000000)
-
-/* A transaction ID. */
-typedef uint64_t txnid_t;
-typedef MDBX_atomic_uint64_t atomic_txnid_t;
-#define PRIaTXN PRIi64
-#define MIN_TXNID UINT64_C(1)
-#define MAX_TXNID (SAFE64_INVALID_THRESHOLD - 1)
-#define INITIAL_TXNID (MIN_TXNID + NUM_METAS - 1)
-#define INVALID_TXNID UINT64_MAX
-/* LY: for testing non-atomic 64-bit txnid on 32-bit arches.
- * #define MDBX_TXNID_STEP (UINT32_MAX / 3) */
-#ifndef MDBX_TXNID_STEP
-#if MDBX_64BIT_CAS
-#define MDBX_TXNID_STEP 1u
-#else
-#define MDBX_TXNID_STEP 2u
-#endif
-#endif /* MDBX_TXNID_STEP */
-
-/* Used for offsets within a single page.
- * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
- * this is plenty. */
-typedef uint16_t indx_t;
-
-#define MEGABYTE ((size_t)1 << 20)
-
-/*----------------------------------------------------------------------------*/
-/* Core structures for database and shared memory (i.e. format definition) */
-#pragma pack(push, 1)
-
-/* Information about a single database in the environment. */
-typedef struct MDBX_db {
-  uint16_t md_flags;        /* see mdbx_dbi_open */
-  uint16_t md_depth;        /* depth of this tree */
-  uint32_t md_xsize;        /* key-size for MDBX_DUPFIXED (LEAF2 pages) */
-  pgno_t md_root;           /* the root page of this tree */
-  pgno_t md_branch_pages;   /* number of internal pages */
-  pgno_t md_leaf_pages;     /* number of leaf pages */
-  pgno_t md_overflow_pages; /* number of overflow pages */
-  uint64_t md_seq;          /* table sequence counter */
-  uint64_t md_entries;      /* number of data items */
-  uint64_t md_mod_txnid;    /* txnid of last committed modification */
-} MDBX_db;
-
-/* database size-related parameters */
-typedef struct mdbx_geo_t {
-  uint16_t grow;   /* datafile growth step in pages */
-  uint16_t shrink; /* datafile shrink threshold in pages */
-  pgno_t lower;    /* minimal size of datafile in pages */
-  pgno_t upper;    /* maximal size of datafile in pages */
-  pgno_t now;      /* current size of datafile in pages */
-  pgno_t next;     /* first unused page in the datafile,
-                    * but actually the file may be shorter. */
-} mdbx_geo_t;
-
-/* Meta page content.
- * A meta page is the start point for accessing a database snapshot.
- * Pages 0-1 are meta pages. Transaction N writes meta page (N % 2). */
-typedef struct MDBX_meta {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with MDBX_DATA_VERSION. */
-  uint32_t mm_magic_and_version[2];
-
-  /* txnid that committed this page, the first of a two-phase-update pair */
-  uint32_t mm_txnid_a[2];
-
-  uint16_t mm_extra_flags;  /* extra DB flags, zero (nothing) for now */
-  uint8_t mm_validator_id;  /* ID of checksum and page validation method,
-                             * zero (nothing) for now */
-  uint8_t mm_extra_pagehdr; /* extra bytes in the page header,
-                             * zero (nothing) for now */
-
-  mdbx_geo_t mm_geo; /* database size-related parameters */
-
-  MDBX_db mm_dbs[CORE_DBS]; /* first is free space, 2nd is main db */
-                            /* The size of pages used in this DB */
-#define mm_psize mm_dbs[FREE_DBI].md_xsize
-/* Any persistent environment flags, see mdbx_env */
-#define mm_flags mm_dbs[FREE_DBI].md_flags
-  MDBX_canary mm_canary;
-
-#define MDBX_DATASIGN_NONE 0u
-#define MDBX_DATASIGN_WEAK 1u
-#define SIGN_IS_STEADY(sign) ((sign) > MDBX_DATASIGN_WEAK)
-#define META_IS_STEADY(meta)                                                   \
-  SIGN_IS_STEADY(unaligned_peek_u64(4, (meta)->mm_datasync_sign))
-  uint32_t mm_datasync_sign[2];
-
-  /* txnid that committed this page, the second of a two-phase-update pair */
-  uint32_t mm_txnid_b[2];
-
-  /* Number of non-meta pages which were put in GC after COW. May be 0 in case
-   * DB was previously handled by libmdbx without corresponding feature.
-   * This value in couple with mr_snapshot_pages_retired allows fast estimation
-   * of "how much reader is restraining GC recycling". */
-  uint32_t mm_pages_retired[2];
-
-  /* The analogue /proc/sys/kernel/random/boot_id or similar to determine
-   * whether the system was rebooted after the last use of the database files.
-   * If there was no reboot, but there is no need to rollback to the last
-   * steady sync point. Zeros mean that no relevant information is available
-   * from the system. */
-  bin128_t mm_bootid;
-
-} MDBX_meta;
-
-/* Common header for all page types. The page type depends on mp_flags.
- *
- * P_BRANCH and P_LEAF pages have unsorted 'MDBX_node's at the end, with
- * sorted mp_ptrs[] entries referring to them. Exception: P_LEAF2 pages
- * omit mp_ptrs and pack sorted MDBX_DUPFIXED values after the page header.
- *
- * P_OVERFLOW records occupy one or more contiguous pages where only the
- * first has a page header. They hold the real data of F_BIGDATA nodes.
- *
- * P_SUBP sub-pages are small leaf "pages" with duplicate data.
- * A node with flag F_DUPDATA but not F_SUBDATA contains a sub-page.
- * (Duplicate data can also go in sub-databases, which use normal pages.)
- *
- * P_META pages contain MDBX_meta, the start point of an MDBX snapshot.
- *
- * Each non-metapage up to MDBX_meta.mm_last_pg is reachable exactly once
- * in the snapshot: Either used by a database or listed in a GC record. */
-typedef struct MDBX_page {
-  union {
-    struct MDBX_page *mp_next; /* for in-memory list of freed pages */
-    uint64_t mp_txnid;         /* txnid that committed this page */
-  };
-  uint16_t mp_leaf2_ksize; /* key size if this is a LEAF2 page */
-#define P_BRANCH 0x01      /* branch page */
-#define P_LEAF 0x02        /* leaf page */
-#define P_OVERFLOW 0x04    /* overflow page */
-#define P_META 0x08        /* meta page */
-#define P_DIRTY 0x10       /* dirty page, also set for P_SUBP pages */
-#define P_LEAF2 0x20       /* for MDBX_DUPFIXED records */
-#define P_SUBP 0x40        /* for MDBX_DUPSORT sub-pages */
-#define P_LOOSE 0x4000     /* page was dirtied then freed, can be reused */
-#define P_KEEP 0x8000      /* leave this page alone during spill */
-  uint16_t mp_flags;
-  union {
-    __anonymous_struct_extension__ struct {
-      indx_t mp_lower; /* lower bound of free space */
-      indx_t mp_upper; /* upper bound of free space */
-    };
-    uint32_t mp_pages; /* number of overflow pages */
-  };
-  pgno_t mp_pgno; /* page number */
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  indx_t mp_ptrs[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_page;
-
-/* Size of the page header, excluding dynamic data at the end */
-#define PAGEHDRSZ ((unsigned)offsetof(MDBX_page, mp_ptrs))
-
-#pragma pack(pop)
-
-#if MDBX_LOCKING == MDBX_LOCKING_WIN32FILES
-#define MDBX_CLOCK_SIGN UINT32_C(0xF10C)
-typedef void mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_SYSV
-
-#define MDBX_CLOCK_SIGN UINT32_C(0xF18D)
-typedef mdbx_pid_t mdbx_ipclock_t;
-#ifndef EOWNERDEAD
-#define EOWNERDEAD MDBX_RESULT_TRUE
-#endif
-
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX2001 ||                                \
-    MDBX_LOCKING == MDBX_LOCKING_POSIX2008
-#define MDBX_CLOCK_SIGN UINT32_C(0x8017)
-typedef pthread_mutex_t mdbx_ipclock_t;
-#elif MDBX_LOCKING == MDBX_LOCKING_POSIX1988
-#define MDBX_CLOCK_SIGN UINT32_C(0xFC29)
-typedef sem_t mdbx_ipclock_t;
-#else
-#error "FIXME"
-#endif /* MDBX_LOCKING */
-
-#if MDBX_LOCKING > MDBX_LOCKING_SYSV && !defined(__cplusplus)
-MDBX_INTERNAL_FUNC int mdbx_ipclock_stub(mdbx_ipclock_t *ipc);
-MDBX_INTERNAL_FUNC int mdbx_ipclock_destroy(mdbx_ipclock_t *ipc);
-#endif /* MDBX_LOCKING */
-
-/* Reader Lock Table
- *
- * Readers don't acquire any locks for their data access. Instead, they
- * simply record their transaction ID in the reader table. The reader
- * mutex is needed just to find an empty slot in the reader table. The
- * slot's address is saved in thread-specific data so that subsequent
- * read transactions started by the same thread need no further locking to
- * proceed.
- *
- * If MDBX_NOTLS is set, the slot address is not saved in thread-specific data.
- * No reader table is used if the database is on a read-only filesystem.
- *
- * Since the database uses multi-version concurrency control, readers don't
- * actually need any locking. This table is used to keep track of which
- * readers are using data from which old transactions, so that we'll know
- * when a particular old transaction is no longer in use. Old transactions
- * that have discarded any data pages can then have those pages reclaimed
- * for use by a later write transaction.
- *
- * The lock table is constructed such that reader slots are aligned with the
- * processor's cache line size. Any slot is only ever used by one thread.
- * This alignment guarantees that there will be no contention or cache
- * thrashing as threads update their own slot info, and also eliminates
- * any need for locking when accessing a slot.
- *
- * A writer thread will scan every slot in the table to determine the oldest
- * outstanding reader transaction. Any freed pages older than this will be
- * reclaimed by the writer. The writer doesn't use any locks when scanning
- * this table. This means that there's no guarantee that the writer will
- * see the most up-to-date reader info, but that's not required for correct
- * operation - all we need is to know the upper bound on the oldest reader,
- * we don't care at all about the newest reader. So the only consequence of
- * reading stale information here is that old pages might hang around a
- * while longer before being reclaimed. That's actually good anyway, because
- * the longer we delay reclaiming old pages, the more likely it is that a
- * string of contiguous pages can be found after coalescing old pages from
- * many old transactions together. */
-
-/* The actual reader record, with cacheline padding. */
-typedef struct MDBX_reader {
-  /* Current Transaction ID when this transaction began, or (txnid_t)-1.
-   * Multiple readers that start at the same time will probably have the
-   * same ID here. Again, it's not important to exclude them from
-   * anything; all we need to know is which version of the DB they
-   * started from so we can avoid overwriting any data used in that
-   * particular version. */
-  MDBX_atomic_uint64_t /* txnid_t */ mr_txnid;
-
-  /* The information we store in a single slot of the reader table.
-   * In addition to a transaction ID, we also record the process and
-   * thread ID that owns a slot, so that we can detect stale information,
-   * e.g. threads or processes that went away without cleaning up.
-   *
-   * NOTE: We currently don't check for stale records.
-   * We simply re-init the table when we know that we're the only process
-   * opening the lock file. */
-
-  /* The thread ID of the thread owning this txn. */
-  MDBX_atomic_uint64_t mr_tid;
-
-  /* The process ID of the process owning this reader txn. */
-  MDBX_atomic_uint32_t mr_pid;
-
-  /* The number of pages used in the reader's MVCC snapshot,
-   * i.e. the value of meta->mm_geo.next and txn->mt_next_pgno */
-  atomic_pgno_t mr_snapshot_pages_used;
-  /* Number of retired pages at the time this reader starts transaction. So,
-   * at any time the difference mm_pages_retired - mr_snapshot_pages_retired
-   * will give the number of pages which this reader restraining from reuse. */
-  MDBX_atomic_uint64_t mr_snapshot_pages_retired;
-} MDBX_reader;
-
-/* The header for the reader table (a memory-mapped lock file). */
-typedef struct MDBX_lockinfo {
-  /* Stamp identifying this as an MDBX file.
-   * It must be set to MDBX_MAGIC with with MDBX_LOCK_VERSION. */
-  uint64_t mti_magic_and_version;
-
-  /* Format of this lock file. Must be set to MDBX_LOCK_FORMAT. */
-  uint32_t mti_os_and_format;
-
-  /* Flags which environment was opened. */
-  MDBX_atomic_uint32_t mti_envmode;
-
-  /* Threshold of un-synced-with-disk pages for auto-sync feature,
-   * zero means no-threshold, i.e. auto-sync is disabled. */
-  atomic_pgno_t mti_autosync_threshold;
-
-  /* Low 32-bit of txnid with which meta-pages was synced,
-   * i.e. for sync-polling in the MDBX_NOMETASYNC mode. */
-  MDBX_atomic_uint32_t mti_meta_sync_txnid;
-
-  /* Period for timed auto-sync feature, i.e. at the every steady checkpoint
-   * the mti_unsynced_timeout sets to the current_time + mti_autosync_period.
-   * The time value is represented in a suitable system-dependent form, for
-   * example clock_gettime(CLOCK_BOOTTIME) or clock_gettime(CLOCK_MONOTONIC).
-   * Zero means timed auto-sync is disabled. */
-  MDBX_atomic_uint64_t mti_autosync_period;
-
-  /* Marker to distinguish uniqueness of DB/CLK.*/
-  MDBX_atomic_uint64_t mti_bait_uniqueness;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Write transaction lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  atomic_txnid_t mti_oldest_reader;
-
-  /* Timestamp of the last steady sync. Value is represented in a suitable
-   * system-dependent form, for example clock_gettime(CLOCK_BOOTTIME) or
-   * clock_gettime(CLOCK_MONOTONIC). */
-  MDBX_atomic_uint64_t mti_sync_timestamp;
-
-  /* Number un-synced-with-disk pages for auto-sync feature. */
-  atomic_pgno_t mti_unsynced_pages;
-
-  /* Number of page which was discarded last time by madvise(MADV_FREE). */
-  atomic_pgno_t mti_discarded_tail;
-
-  /* Timestamp of the last readers check. */
-  MDBX_atomic_uint64_t mti_reader_check_timestamp;
-
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-
-  /* Readeaders registration lock. */
-#if MDBX_LOCKING > 0
-      mdbx_ipclock_t mti_rlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  /* The number of slots that have been used in the reader table.
-   * This always records the maximum count, it is not decremented
-   * when readers release their slots. */
-  MDBX_atomic_uint32_t mti_numreaders;
-  MDBX_atomic_uint32_t mti_readers_refresh_flag;
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  alignas(MDBX_CACHELINE_SIZE) /* cacheline ---------------------------------*/
-      MDBX_reader mti_readers[] /* dynamic size */;
-#endif /* C99 */
-} MDBX_lockinfo;
-
-/* Lockfile format signature: version, features and field layout */
-#define MDBX_LOCK_FORMAT                                                       \
-  (MDBX_CLOCK_SIGN * 27733 + (unsigned)sizeof(MDBX_reader) * 13 +              \
-   (unsigned)offsetof(MDBX_reader, mr_snapshot_pages_used) * 251 +             \
-   (unsigned)offsetof(MDBX_lockinfo, mti_oldest_reader) * 83 +                 \
-   (unsigned)offsetof(MDBX_lockinfo, mti_numreaders) * 37 +                    \
-   (unsigned)offsetof(MDBX_lockinfo, mti_readers) * 29)
-
-#define MDBX_DATA_MAGIC                                                        \
-  ((MDBX_MAGIC << 8) + MDBX_PNL_ASCENDING * 64 + MDBX_DATA_VERSION)
-#define MDBX_DATA_MAGIC_DEVEL ((MDBX_MAGIC << 8) + 255)
-
-#define MDBX_LOCK_MAGIC ((MDBX_MAGIC << 8) + MDBX_LOCK_VERSION)
-
-#ifndef MDBX_ASSUME_MALLOC_OVERHEAD
-#define MDBX_ASSUME_MALLOC_OVERHEAD (sizeof(void *) * 2u)
-#endif /* MDBX_ASSUME_MALLOC_OVERHEAD */
-
-/* The maximum size of a database page.
- *
- * It is 64K, but value-PAGEHDRSZ must fit in MDBX_page.mp_upper.
- *
- * MDBX will use database pages < OS pages if needed.
- * That causes more I/O in write transactions: The OS must
- * know (read) the whole page before writing a partial page.
- *
- * Note that we don't currently support Huge pages. On Linux,
- * regular data files cannot use Huge pages, and in general
- * Huge pages aren't actually pageable. We rely on the OS
- * demand-pager to read our data and page it out when memory
- * pressure from other processes is high. So until OSs have
- * actual paging support for Huge pages, they're not viable. */
-#define MAX_PAGESIZE MDBX_MAX_PAGESIZE
-#define MIN_PAGESIZE MDBX_MIN_PAGESIZE
-
-#define MIN_MAPSIZE (MIN_PAGESIZE * MIN_PAGENO)
-#if defined(_WIN32) || defined(_WIN64)
-#define MAX_MAPSIZE32 UINT32_C(0x38000000)
-#else
-#define MAX_MAPSIZE32 UINT32_C(0x7f000000)
-#endif
-#define MAX_MAPSIZE64 (MAX_PAGENO * (uint64_t)MAX_PAGESIZE)
-
-#if MDBX_WORDBITS >= 64
-#define MAX_MAPSIZE MAX_MAPSIZE64
-#define MDBX_READERS_LIMIT                                                     \
-  ((MAX_PAGESIZE - sizeof(MDBX_lockinfo)) / sizeof(MDBX_reader))
-#define MDBX_PGL_LIMIT MAX_PAGENO
-#else
-#define MDBX_READERS_LIMIT 1024
-#define MAX_MAPSIZE MAX_MAPSIZE32
-#define MDBX_PGL_LIMIT (MAX_MAPSIZE32 / MIN_PAGESIZE)
-#endif /* MDBX_WORDBITS */
-
-/*----------------------------------------------------------------------------*/
-
-/* An PNL is an Page Number List, a sorted array of IDs.
- * The first element of the array is a counter for how many actual page-numbers
- * are in the list. By default PNLs are sorted in descending order, this allow
- * cut off a page with lowest pgno (at the tail) just truncating the list. The
- * sort order of PNLs is controlled by the MDBX_PNL_ASCENDING build option. */
-typedef pgno_t *MDBX_PNL;
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_ORDERED(first, last) ((first) < (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) >= (last))
-#else
-#define MDBX_PNL_ORDERED(first, last) ((first) > (last))
-#define MDBX_PNL_DISORDERED(first, last) ((first) <= (last))
-#endif
-
-/* List of txnid, only for MDBX_txn.tw.lifo_reclaimed */
-typedef txnid_t *MDBX_TXL;
-
-/* An Dirty-Page list item is an pgno/pointer pair. */
-typedef struct MDBX_dp {
-  pgno_t pgno;
-  MDBX_page *ptr;
-} MDBX_dp;
-
-/* An DPL (dirty-page list) is a sorted array of MDBX_DPs. */
-typedef struct MDBX_dpl {
-  unsigned sorted;
-  unsigned length;
-  unsigned allocated;
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  MDBX_dp items[] /* dynamic size with holes at zero and after the last */;
-#endif
-} MDBX_dpl;
-
-/* PNL sizes */
-#define MDBX_PNL_GRANULATE 1024
-#define MDBX_PNL_INITIAL                                                       \
-  (MDBX_PNL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(pgno_t))
-
-#define MDBX_TXL_GRANULATE 32
-#define MDBX_TXL_INITIAL                                                       \
-  (MDBX_TXL_GRANULATE - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-#define MDBX_TXL_MAX                                                           \
-  ((1u << 17) - 2 - MDBX_ASSUME_MALLOC_OVERHEAD / sizeof(txnid_t))
-
-#define MDBX_PNL_ALLOCLEN(pl) ((pl)[-1])
-#define MDBX_PNL_SIZE(pl) ((pl)[0])
-#define MDBX_PNL_FIRST(pl) ((pl)[1])
-#define MDBX_PNL_LAST(pl) ((pl)[MDBX_PNL_SIZE(pl)])
-#define MDBX_PNL_BEGIN(pl) (&(pl)[1])
-#define MDBX_PNL_END(pl) (&(pl)[MDBX_PNL_SIZE(pl) + 1])
-
-#if MDBX_PNL_ASCENDING
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_FIRST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_LAST(pl)
-#else
-#define MDBX_PNL_LEAST(pl) MDBX_PNL_LAST(pl)
-#define MDBX_PNL_MOST(pl) MDBX_PNL_FIRST(pl)
-#endif
-
-#define MDBX_PNL_SIZEOF(pl) ((MDBX_PNL_SIZE(pl) + 1) * sizeof(pgno_t))
-#define MDBX_PNL_IS_EMPTY(pl) (MDBX_PNL_SIZE(pl) == 0)
-
-/*----------------------------------------------------------------------------*/
-/* Internal structures */
-
-/* Auxiliary DB info.
- * The information here is mostly static/read-only. There is
- * only a single copy of this record in the environment. */
-typedef struct MDBX_dbx {
-  MDBX_val md_name;                /* name of the database */
-  MDBX_cmp_func *md_cmp;           /* function for comparing keys */
-  MDBX_cmp_func *md_dcmp;          /* function for comparing data items */
-  size_t md_klen_min, md_klen_max; /* min/max key length for the database */
-  size_t md_vlen_min,
-      md_vlen_max; /* min/max value/data length for the database */
-} MDBX_dbx;
-
-/* A database transaction.
- * Every operation requires a transaction handle. */
-struct MDBX_txn {
-#define MDBX_MT_SIGNATURE UINT32_C(0x93D53A31)
-  size_t mt_signature;
-  MDBX_txn *mt_parent; /* parent of a nested txn */
-  /* Nested txn under this txn, set together with flag MDBX_TXN_HAS_CHILD */
-  MDBX_txn *mt_child;
-  mdbx_geo_t mt_geo;
-  /* next unallocated page */
-#define mt_next_pgno mt_geo.next
-  /* corresponding to the current size of datafile */
-#define mt_end_pgno mt_geo.now
-
-  /* Transaction Flags */
-  /* mdbx_txn_begin() flags */
-#define MDBX_TXN_RO_BEGIN_FLAGS (MDBX_TXN_RDONLY | MDBX_TXN_RDONLY_PREPARE)
-#define MDBX_TXN_RW_BEGIN_FLAGS                                                \
-  (MDBX_TXN_NOMETASYNC | MDBX_TXN_NOSYNC | MDBX_TXN_TRY)
-  /* Additional flag for mdbx_sync_locked() */
-#define MDBX_SHRINK_ALLOWED UINT32_C(0x40000000)
-
-  /* internal txn flags */
-#define MDBX_TXN_FINISHED 0x01  /* txn is finished or never began */
-#define MDBX_TXN_ERROR 0x02     /* txn is unusable after an error */
-#define MDBX_TXN_DIRTY 0x04     /* must write, even if dirty list is empty */
-#define MDBX_TXN_SPILLS 0x08    /* txn or a parent has spilled pages */
-#define MDBX_TXN_HAS_CHILD 0x10 /* txn has an MDBX_txn.mt_child */
-  /* most operations on the txn are currently illegal */
-#define MDBX_TXN_BLOCKED                                                       \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_HAS_CHILD)
-
-#define TXN_FLAGS                                                              \
-  (MDBX_TXN_FINISHED | MDBX_TXN_ERROR | MDBX_TXN_DIRTY | MDBX_TXN_SPILLS |     \
-   MDBX_TXN_HAS_CHILD)
-
-#if (TXN_FLAGS & (MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS)) ||       \
-    ((MDBX_TXN_RW_BEGIN_FLAGS | MDBX_TXN_RO_BEGIN_FLAGS | TXN_FLAGS) &         \
-     MDBX_SHRINK_ALLOWED)
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-  unsigned mt_flags;
-  /* The ID of this transaction. IDs are integers incrementing from 1.
-   * Only committed write transactions increment the ID. If a transaction
-   * aborts, the ID may be re-used by the next writer. */
-  txnid_t mt_txnid;
-  MDBX_env *mt_env; /* the DB environment */
-  /* Array of records for each DB known in the environment. */
-  MDBX_dbx *mt_dbxs;
-  /* Array of MDBX_db records for each known DB */
-  MDBX_db *mt_dbs;
-  /* Array of sequence numbers for each DB handle */
-  unsigned *mt_dbiseqs;
-
-  /* Transaction DBI Flags */
-#define DBI_DIRTY MDBX_DBI_DIRTY /* DB was written in this txn */
-#define DBI_STALE MDBX_DBI_STALE /* Named-DB record is older than txnID */
-#define DBI_FRESH MDBX_DBI_FRESH /* Named-DB handle opened in this txn */
-#define DBI_CREAT MDBX_DBI_CREAT /* Named-DB handle created in this txn */
-#define DBI_VALID 0x10           /* DB handle is valid, see also DB_VALID */
-#define DBI_USRVALID 0x20        /* As DB_VALID, but not set for FREE_DBI */
-#define DBI_DUPDATA 0x40         /* DB is MDBX_DUPSORT data */
-#define DBI_AUDITED 0x80         /* Internal flag for accounting during audit */
-  /* Array of flags for each DB */
-  uint8_t *mt_dbistate;
-  /* Number of DB records in use, or 0 when the txn is finished.
-   * This number only ever increments until the txn finishes; we
-   * don't decrement it when individual DB handles are closed. */
-  MDBX_dbi mt_numdbs;
-  size_t mt_owner; /* thread ID that owns this transaction */
-  MDBX_canary mt_canary;
-  void *mt_userctx; /* User-settable context */
-
-  union {
-    struct {
-      /* For read txns: This thread/txn's reader table slot, or NULL. */
-      MDBX_reader *reader;
-    } to;
-    struct {
-      /* In write txns, array of cursors for each DB */
-      MDBX_cursor **cursors;
-      pgno_t *reclaimed_pglist; /* Reclaimed GC pages */
-      txnid_t last_reclaimed;   /* ID of last used record */
-#if MDBX_ENABLE_REFUND
-      pgno_t loose_refund_wl /* FIXME: describe */;
-#endif /* MDBX_ENABLE_REFUND */
-      /* dirtylist room: Dirty array size - dirty pages visible to this txn.
-       * Includes ancestor txns' dirty pages not hidden by other txns'
-       * dirty/spilled pages. Thus commit(nested txn) has room to merge
-       * dirtylist into mt_parent after freeing hidden mt_parent pages. */
-      unsigned dirtyroom;
-      /* For write txns: Modified pages. Sorted when not MDBX_WRITEMAP. */
-      MDBX_dpl *dirtylist;
-      /* The list of reclaimed txns from GC */
-      MDBX_TXL lifo_reclaimed;
-      /* The list of pages that became unused during this transaction. */
-      MDBX_PNL retired_pages;
-      /* The list of loose pages that became unused and may be reused
-       * in this transaction, linked through `mp_next`. */
-      MDBX_page *loose_pages;
-      /* Number of loose pages (tw.loose_pages) */
-      unsigned loose_count;
-      /* The sorted list of dirty pages we temporarily wrote to disk
-       * because the dirty list was full. page numbers in here are
-       * shifted left by 1, deleted slots have the LSB set. */
-      MDBX_PNL spill_pages;
-      unsigned spill_least_removed;
-    } tw;
-  };
-};
-
-#if MDBX_WORDBITS >= 64
-#define CURSOR_STACK 32
-#else
-#define CURSOR_STACK 24
-#endif
-
-struct MDBX_xcursor;
-
-/* Cursors are used for all DB operations.
- * A cursor holds a path of (page pointer, key index) from the DB
- * root to a position in the DB, plus other state. MDBX_DUPSORT
- * cursors include an xcursor to the current data item. Write txns
- * track their cursors and keep them up to date when data moves.
- * Exception: An xcursor's pointer to a P_SUBP page can be stale.
- * (A node with F_DUPDATA but no F_SUBDATA contains a subpage). */
-struct MDBX_cursor {
-#define MDBX_MC_LIVE UINT32_C(0xFE05D5B1)
-#define MDBX_MC_READY4CLOSE UINT32_C(0x2817A047)
-#define MDBX_MC_WAIT4EOT UINT32_C(0x90E297A7)
-  uint32_t mc_signature;
-  /* The database handle this cursor operates on */
-  MDBX_dbi mc_dbi;
-  /* Next cursor on this DB in this txn */
-  MDBX_cursor *mc_next;
-  /* Backup of the original cursor if this cursor is a shadow */
-  MDBX_cursor *mc_backup;
-  /* Context used for databases with MDBX_DUPSORT, otherwise NULL */
-  struct MDBX_xcursor *mc_xcursor;
-  /* The transaction that owns this cursor */
-  MDBX_txn *mc_txn;
-  /* The database record for this cursor */
-  MDBX_db *mc_db;
-  /* The database auxiliary record for this cursor */
-  MDBX_dbx *mc_dbx;
-  /* The mt_dbistate for this database */
-  uint8_t *mc_dbistate;
-  unsigned mc_snum; /* number of pushed pages */
-  unsigned mc_top;  /* index of top page, normally mc_snum-1 */
-
-  /* Cursor state flags. */
-#define C_INITIALIZED 0x01 /* cursor has been initialized and is valid */
-#define C_EOF 0x02         /* No more data */
-#define C_SUB 0x04         /* Cursor is a sub-cursor */
-#define C_DEL 0x08         /* last op was a cursor_del */
-#define C_UNTRACK 0x10     /* Un-track cursor when closing */
-#define C_RECLAIMING 0x20  /* GC lookup is prohibited */
-#define C_GCFREEZE 0x40    /* reclaimed_pglist must not be updated */
-
-  /* Cursor checking flags. */
-#define C_COPYING 0x100  /* skip key-value length check (copying simplify) */
-#define C_UPDATING 0x200 /* update/rebalance pending */
-#define C_RETIRING 0x400 /* refs to child pages may be invalid */
-#define C_SKIPORD 0x800  /* don't check keys ordering */
-
-  unsigned mc_flags;              /* see mdbx_cursor */
-  MDBX_page *mc_pg[CURSOR_STACK]; /* stack of pushed pages */
-  indx_t mc_ki[CURSOR_STACK];     /* stack of page indices */
-};
-
-/* Context for sorted-dup records.
- * We could have gone to a fully recursive design, with arbitrarily
- * deep nesting of sub-databases. But for now we only handle these
- * levels - main DB, optional sub-DB, sorted-duplicate DB. */
-typedef struct MDBX_xcursor {
-  /* A sub-cursor for traversing the Dup DB */
-  MDBX_cursor mx_cursor;
-  /* The database record for this Dup DB */
-  MDBX_db mx_db;
-  /* The auxiliary DB record for this Dup DB */
-  MDBX_dbx mx_dbx;
-  /* The mt_dbistate for this Dup DB */
-  uint8_t mx_dbistate;
-} MDBX_xcursor;
-
-typedef struct MDBX_cursor_couple {
-  MDBX_cursor outer;
-  void *mc_userctx; /* User-settable context */
-  MDBX_xcursor inner;
-} MDBX_cursor_couple;
-
-/* The database environment. */
-struct MDBX_env {
-#define MDBX_ME_SIGNATURE UINT32_C(0x9A899641)
-  MDBX_atomic_uint32_t me_signature;
-  /* Failed to update the meta page. Probably an I/O error. */
-#define MDBX_FATAL_ERROR UINT32_C(0x80000000)
-  /* Some fields are initialized. */
-#define MDBX_ENV_ACTIVE UINT32_C(0x20000000)
-  /* me_txkey is set */
-#define MDBX_ENV_TXKEY UINT32_C(0x10000000)
-  /* Legacy MDBX_MAPASYNC (prior v0.9) */
-#define MDBX_DEPRECATED_MAPASYNC UINT32_C(0x100000)
-#define ENV_INTERNAL_FLAGS (MDBX_FATAL_ERROR | MDBX_ENV_ACTIVE | MDBX_ENV_TXKEY)
-  uint32_t me_flags;
-  mdbx_mmap_t me_dxb_mmap; /* The main data file */
-#define me_map me_dxb_mmap.dxb
-#define me_lazy_fd me_dxb_mmap.fd
-  mdbx_filehandle_t me_dsync_fd;
-  mdbx_mmap_t me_lck_mmap; /* The lock file */
-#define me_lfd me_lck_mmap.fd
-#define me_lck me_lck_mmap.lck
-
-  unsigned me_psize;    /* DB page size, initialized from me_os_psize */
-  uint8_t me_psize2log; /* log2 of DB page size */
-  int8_t me_stuck_meta; /* recovery-only: target meta page or less that zero */
-  unsigned me_os_psize; /* OS page size, from mdbx_syspagesize() */
-  unsigned me_maxreaders; /* size of the reader table */
-  mdbx_fastmutex_t me_dbi_lock;
-  MDBX_dbi me_numdbs;         /* number of DBs opened */
-  MDBX_dbi me_maxdbs;         /* size of the DB table */
-  uint32_t me_pid;            /* process ID of this env */
-  mdbx_thread_key_t me_txkey; /* thread-key for readers */
-  char *me_pathname;          /* path to the DB files */
-  void *me_pbuf;              /* scratch area for DUPSORT put() */
-  MDBX_txn *me_txn;           /* current write transaction */
-  MDBX_txn *me_txn0;          /* prealloc'd write transaction */
-
-  /* write-txn lock */
-#if MDBX_LOCKING == MDBX_LOCKING_SYSV
-  union {
-    key_t key;
-    int semid;
-  } me_sysv_ipc;
-#endif /* MDBX_LOCKING == MDBX_LOCKING_SYSV */
-
-#if MDBX_LOCKING > 0
-  mdbx_ipclock_t *me_wlock;
-#endif /* MDBX_LOCKING > 0 */
-
-  MDBX_dbx *me_dbxs;         /* array of static DB info */
-  uint16_t *me_dbflags;      /* array of flags from MDBX_db.md_flags */
-  unsigned *me_dbiseqs;      /* array of dbi sequence numbers */
-  atomic_txnid_t *me_oldest; /* ID of oldest reader last time we looked */
-  MDBX_page *me_dp_reserve;  /* list of malloc'd blocks for re-use */
-  /* PNL of pages that became unused in a write txn */
-  MDBX_PNL me_retired_pages;
-  /* Number of freelist items that can fit in a single overflow page */
-  unsigned me_maxgc_ov1page;
-  unsigned me_branch_nodemax; /* max size of a branch-node */
-  uint32_t me_live_reader;    /* have liveness lock in reader table */
-  void *me_userctx;           /* User-settable context */
-  MDBX_atomic_uint64_t *me_sync_timestamp;
-  MDBX_atomic_uint64_t *me_autosync_period;
-  atomic_pgno_t *me_unsynced_pages;
-  atomic_pgno_t *me_autosync_threshold;
-  atomic_pgno_t *me_discarded_tail;
-  MDBX_atomic_uint32_t *me_meta_sync_txnid;
-  MDBX_hsr_func *me_hsr_callback; /* Callback for kicking laggard readers */
-  unsigned me_dp_reserve_len;
-  struct {
-    unsigned dp_reserve_limit;
-    unsigned rp_augment_limit;
-    unsigned dp_limit;
-    unsigned dp_initial;
-    uint8_t dp_loose_limit;
-    uint8_t spill_max_denominator;
-    uint8_t spill_min_denominator;
-    uint8_t spill_parent4child_denominator;
-  } me_options;
-  struct {
-#if MDBX_LOCKING > 0
-    mdbx_ipclock_t wlock;
-#endif /* MDBX_LOCKING > 0 */
-    atomic_txnid_t oldest;
-    MDBX_atomic_uint64_t sync_timestamp;
-    MDBX_atomic_uint64_t autosync_period;
-    atomic_pgno_t autosync_pending;
-    atomic_pgno_t autosync_threshold;
-    atomic_pgno_t discarded_tail;
-    MDBX_atomic_uint32_t meta_sync_txnid;
-  } me_lckless_stub;
-#if MDBX_DEBUG
-  MDBX_assert_func *me_assert_func; /*  Callback for assertion failures */
-#endif
-#ifdef MDBX_USE_VALGRIND
-  int me_valgrind_handle;
-#endif
-#if defined(MDBX_USE_VALGRIND) || defined(__SANITIZE_ADDRESS__)
-  pgno_t me_poison_edge;
-#endif /* MDBX_USE_VALGRIND || __SANITIZE_ADDRESS__ */
-  MDBX_env *me_lcklist_next;
-
-  /* struct me_dbgeo used for accepting db-geo params from user for the new
-   * database creation, i.e. when mdbx_env_set_geometry() was called before
-   * mdbx_env_open(). */
-  struct {
-    size_t lower;  /* minimal size of datafile */
-    size_t upper;  /* maximal size of datafile */
-    size_t now;    /* current size of datafile */
-    size_t grow;   /* step to grow datafile */
-    size_t shrink; /* threshold to shrink datafile */
-  } me_dbgeo;
-
-#if defined(_WIN32) || defined(_WIN64)
-  MDBX_srwlock me_remap_guard;
-  /* Workaround for LockFileEx and WriteFile multithread bug */
-  CRITICAL_SECTION me_windowsbug_lock;
-#else
-  mdbx_fastmutex_t me_remap_guard;
-#endif
-};
-
-#ifndef __cplusplus
-/*----------------------------------------------------------------------------*/
-/* Debug and Logging stuff */
-
-#define MDBX_RUNTIME_FLAGS_INIT                                                \
-  ((MDBX_DEBUG) > 0) * MDBX_DBG_ASSERT + ((MDBX_DEBUG) > 1) * MDBX_DBG_AUDIT
-
-extern uint8_t mdbx_runtime_flags;
-extern uint8_t mdbx_loglevel;
-extern MDBX_debug_func *mdbx_debug_logger;
-
-MDBX_INTERNAL_FUNC void MDBX_PRINTF_ARGS(4, 5)
-    mdbx_debug_log(int level, const char *function, int line, const char *fmt,
-                   ...) MDBX_PRINTF_ARGS(4, 5);
-MDBX_INTERNAL_FUNC void mdbx_debug_log_va(int level, const char *function,
-                                          int line, const char *fmt,
-                                          va_list args);
-
-#define mdbx_log_enabled(msg) unlikely(msg <= mdbx_loglevel)
-
-#if MDBX_DEBUG
-
-#define mdbx_assert_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_ASSERT)
-
-#define mdbx_audit_enabled() unlikely(mdbx_runtime_flags &MDBX_DBG_AUDIT)
-
-#else /* MDBX_DEBUG */
-
-#define mdbx_audit_enabled() (0)
-
-#if !defined(NDEBUG) || defined(MDBX_FORCE_ASSERTIONS)
-#define mdbx_assert_enabled() (1)
-#else
-#define mdbx_assert_enabled() (0)
-#endif /* NDEBUG */
-
-#endif /* MDBX_DEBUG */
-
-#if !MDBX_DEBUG && defined(__ANDROID_API__)
-#define mdbx_assert_fail(env, msg, func, line)                                 \
-  __android_log_assert(msg, "mdbx", "%s:%u", func, line)
-#else
-void mdbx_assert_fail(const MDBX_env *env, const char *msg, const char *func,
-                      int line);
-#endif
-
-#define mdbx_debug_extra(fmt, ...)                                             \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, __func__, __LINE__, fmt, __VA_ARGS__);    \
-  } while (0)
-
-#define mdbx_debug_extra_print(fmt, ...)                                       \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_EXTRA))                        \
-      mdbx_debug_log(MDBX_LOG_EXTRA, NULL, 0, fmt, __VA_ARGS__);               \
-  } while (0)
-
-#define mdbx_trace(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_TRACE))                        \
-      mdbx_debug_log(MDBX_LOG_TRACE, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_debug(fmt, ...)                                                   \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_DEBUG))                        \
-      mdbx_debug_log(MDBX_LOG_DEBUG, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_verbose(fmt, ...)                                                 \
-  do {                                                                         \
-    if (MDBX_DEBUG && mdbx_log_enabled(MDBX_LOG_VERBOSE))                      \
-      mdbx_debug_log(MDBX_LOG_VERBOSE, __func__, __LINE__, fmt "\n",           \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_notice(fmt, ...)                                                  \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_NOTICE))                                     \
-      mdbx_debug_log(MDBX_LOG_NOTICE, __func__, __LINE__, fmt "\n",            \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_warning(fmt, ...)                                                 \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_WARN))                                       \
-      mdbx_debug_log(MDBX_LOG_WARN, __func__, __LINE__, fmt "\n",              \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_error(fmt, ...)                                                   \
-  do {                                                                         \
-    if (mdbx_log_enabled(MDBX_LOG_ERROR))                                      \
-      mdbx_debug_log(MDBX_LOG_ERROR, __func__, __LINE__, fmt "\n",             \
-                     __VA_ARGS__);                                             \
-  } while (0)
-
-#define mdbx_fatal(fmt, ...)                                                   \
-  mdbx_debug_log(MDBX_LOG_FATAL, __func__, __LINE__, fmt "\n", __VA_ARGS__);
-
-#define mdbx_ensure_msg(env, expr, msg)                                        \
-  do {                                                                         \
-    if (unlikely(!(expr)))                                                     \
-      mdbx_assert_fail(env, msg, __func__, __LINE__);                          \
-  } while (0)
-
-#define mdbx_ensure(env, expr) mdbx_ensure_msg(env, expr, #expr)
-
-/* assert(3) variant in environment context */
-#define mdbx_assert(env, expr)                                                 \
-  do {                                                                         \
-    if (mdbx_assert_enabled())                                                 \
-      mdbx_ensure(env, expr);                                                  \
-  } while (0)
-
-/* assert(3) variant in cursor context */
-#define mdbx_cassert(mc, expr) mdbx_assert((mc)->mc_txn->mt_env, expr)
-
-/* assert(3) variant in transaction context */
-#define mdbx_tassert(txn, expr) mdbx_assert((txn)->mt_env, expr)
-
-#ifndef MDBX_TOOLS /* Avoid using internal mdbx_assert() */
-#undef assert
-#define assert(expr) mdbx_assert(NULL, expr)
-#endif
-
-/*----------------------------------------------------------------------------*/
-/* Cache coherence and mmap invalidation */
-
-#if MDBX_CPU_WRITEBACK_INCOHERENT
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_memory_barrier()
-#else
-#define mdbx_flush_incoherent_cpu_writeback() mdbx_compiler_barrier()
-#endif /* MDBX_CPU_WRITEBACK_INCOHERENT */
-
-static __maybe_unused __inline void
-mdbx_flush_incoherent_mmap(void *addr, size_t nbytes, const intptr_t pagesize) {
-#if MDBX_MMAP_INCOHERENT_FILE_WRITE
-  char *const begin = (char *)(-pagesize & (intptr_t)addr);
-  char *const end =
-      (char *)(-pagesize & (intptr_t)((char *)addr + nbytes + pagesize - 1));
-  int err = msync(begin, end - begin, MS_SYNC | MS_INVALIDATE) ? errno : 0;
-  mdbx_assert(nullptr, err == 0);
-  (void)err;
-#else
-  (void)pagesize;
-#endif /* MDBX_MMAP_INCOHERENT_FILE_WRITE */
-
-#if MDBX_MMAP_INCOHERENT_CPU_CACHE
-#ifdef DCACHE
-  /* MIPS has cache coherency issues.
-   * Note: for any nbytes >= on-chip cache size, entire is flushed. */
-  cacheflush(addr, nbytes, DCACHE);
-#else
-#error "Oops, cacheflush() not available"
-#endif /* DCACHE */
-#endif /* MDBX_MMAP_INCOHERENT_CPU_CACHE */
-
-#if !MDBX_MMAP_INCOHERENT_FILE_WRITE && !MDBX_MMAP_INCOHERENT_CPU_CACHE
-  (void)addr;
-  (void)nbytes;
-#endif
-}
-
-/*----------------------------------------------------------------------------*/
-/* Internal prototypes */
-
-MDBX_INTERNAL_FUNC int mdbx_cleanup_dead_readers(MDBX_env *env, int rlocked,
-                                                 int *dead);
-MDBX_INTERNAL_FUNC int mdbx_rthc_alloc(mdbx_thread_key_t *key,
-                                       MDBX_reader *begin, MDBX_reader *end);
-MDBX_INTERNAL_FUNC void mdbx_rthc_remove(const mdbx_thread_key_t key);
-
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_init(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_global_dtor(void);
-MDBX_INTERNAL_FUNC void mdbx_rthc_thread_dtor(void *ptr);
-
-static __maybe_unused __inline void mdbx_jitter4testing(bool tiny) {
-#if MDBX_DEBUG
-  if (MDBX_DBG_JITTER & mdbx_runtime_flags)
-    mdbx_osal_jitter(tiny);
-#else
-  (void)tiny;
-#endif
-}
-
-#endif /* !__cplusplus */
-
-#define MDBX_IS_ERROR(rc)                                                      \
-  ((rc) != MDBX_RESULT_TRUE && (rc) != MDBX_RESULT_FALSE)
-
-/* Internal error codes, not exposed outside libmdbx */
-#define MDBX_NO_ROOT (MDBX_LAST_ADDED_ERRCODE + 10)
-
-/* Debugging output value of a cursor DBI: Negative in a sub-cursor. */
-#define DDBI(mc)                                                               \
-  (((mc)->mc_flags & C_SUB) ? -(int)(mc)->mc_dbi : (int)(mc)->mc_dbi)
-
-/* Key size which fits in a DKBUF. */
-#define DKBUF_MAXKEYSIZE 511 /* FIXME */
-
-#if MDBX_DEBUG
-#define DKBUF char _kbuf[DKBUF_MAXKEYSIZE * 4 + 2]
-#define DKEY(x) mdbx_dump_val(x, _kbuf, DKBUF_MAXKEYSIZE * 2 + 1)
-#define DVAL(x)                                                                \
-  mdbx_dump_val(x, _kbuf + DKBUF_MAXKEYSIZE * 2 + 1, DKBUF_MAXKEYSIZE * 2 + 1)
-#else
-#define DKBUF ((void)(0))
-#define DKEY(x) ("-")
-#define DVAL(x) ("-")
-#endif
-
-/* An invalid page number.
- * Mainly used to denote an empty tree. */
-#define P_INVALID (~(pgno_t)0)
-
-/* Test if the flags f are set in a flag word w. */
-#define F_ISSET(w, f) (((w) & (f)) == (f))
-
-/* Round n up to an even number. */
-#define EVEN(n) (((n) + 1U) & -2) /* sign-extending -2 to match n+1U */
-
-/* Default size of memory map.
- * This is certainly too small for any actual applications. Apps should
- * always set  the size explicitly using mdbx_env_set_mapsize(). */
-#define DEFAULT_MAPSIZE MEGABYTE
-
-/* Number of slots in the reader table.
- * This value was chosen somewhat arbitrarily. The 61 is a prime number,
- * and such readers plus a couple mutexes fit into single 4KB page.
- * Applications should set the table size using mdbx_env_set_maxreaders(). */
-#define DEFAULT_READERS 61
-
-/* Test if a page is a leaf page */
-#define IS_LEAF(p) (((p)->mp_flags & P_LEAF) != 0)
-/* Test if a page is a LEAF2 page */
-#define IS_LEAF2(p) unlikely(((p)->mp_flags & P_LEAF2) != 0)
-/* Test if a page is a branch page */
-#define IS_BRANCH(p) (((p)->mp_flags & P_BRANCH) != 0)
-/* Test if a page is an overflow page */
-#define IS_OVERFLOW(p) unlikely(((p)->mp_flags & P_OVERFLOW) != 0)
-/* Test if a page is a sub page */
-#define IS_SUBP(p) (((p)->mp_flags & P_SUBP) != 0)
-/* Test if a page is dirty */
-#define IS_DIRTY(p) (((p)->mp_flags & P_DIRTY) != 0)
-
-#define PAGETYPE(p) ((p)->mp_flags & (P_BRANCH | P_LEAF | P_LEAF2 | P_OVERFLOW))
-
-/* Header for a single key/data pair within a page.
- * Used in pages of type P_BRANCH and P_LEAF without P_LEAF2.
- * We guarantee 2-byte alignment for 'MDBX_node's.
- *
- * Leaf node flags describe node contents.  F_BIGDATA says the node's
- * data part is the page number of an overflow page with actual data.
- * F_DUPDATA and F_SUBDATA can be combined giving duplicate data in
- * a sub-page/sub-database, and named databases (just F_SUBDATA). */
-typedef struct MDBX_node {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  union {
-    uint32_t mn_dsize;
-    uint32_t mn_pgno32;
-  };
-  uint8_t mn_flags; /* see mdbx_node flags */
-  uint8_t mn_extra;
-  uint16_t mn_ksize; /* key size */
-#else
-  uint16_t mn_ksize; /* key size */
-  uint8_t mn_extra;
-  uint8_t mn_flags; /* see mdbx_node flags */
-  union {
-    uint32_t mn_pgno32;
-    uint32_t mn_dsize;
-  };
-#endif /* __BYTE_ORDER__ */
-
-  /* mdbx_node Flags */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
-#define F_DUPDATA 0x04 /* data has duplicates */
-
-  /* valid flags for mdbx_node_add() */
-#define NODE_ADD_FLAGS (F_DUPDATA | F_SUBDATA | MDBX_RESERVE | MDBX_APPEND)
-
-#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
-    (!defined(__cplusplus) && defined(_MSC_VER))
-  uint8_t mn_data[] /* key and data are appended here */;
-#endif /* C99 */
-} MDBX_node;
-
-#define DB_PERSISTENT_FLAGS                                                    \
-  (MDBX_REVERSEKEY | MDBX_DUPSORT | MDBX_INTEGERKEY | MDBX_DUPFIXED |          \
-   MDBX_INTEGERDUP | MDBX_REVERSEDUP)
-
-/* mdbx_dbi_open() flags */
-#define DB_USABLE_FLAGS (DB_PERSISTENT_FLAGS | MDBX_CREATE | MDBX_DB_ACCEDE)
-
-#define DB_VALID 0x8000 /* DB handle is valid, for me_dbflags */
-#define DB_INTERNAL_FLAGS DB_VALID
-
-#if DB_INTERNAL_FLAGS & DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-#if DB_PERSISTENT_FLAGS & ~DB_USABLE_FLAGS
-#error "Oops, some flags overlapped or wrong"
-#endif
-
-/* max number of pages to commit in one writev() call */
-#define MDBX_COMMIT_PAGES 64
-#if defined(IOV_MAX) && IOV_MAX < MDBX_COMMIT_PAGES /* sysconf(_SC_IOV_MAX) */
-#undef MDBX_COMMIT_PAGES
-#define MDBX_COMMIT_PAGES IOV_MAX
-#endif
-
-/*
- *                /
- *                | -1, a < b
- * CMP2INT(a,b) = <  0, a == b
- *                |  1, a > b
- *                \
- */
-#if 1
-/* LY: fast enough on most systems */
-#define CMP2INT(a, b) (((b) > (a)) ? -1 : (a) > (b))
-#else
-#define CMP2INT(a, b) (((a) > (b)) - ((b) > (a)))
-#endif
-
-/* Do not spill pages to disk if txn is getting full, may fail instead */
-#define MDBX_NOSPILL 0x8000
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_add(pgno_t base, pgno_t augend) {
-  assert(base <= MAX_PAGENO);
-  return (augend < MAX_PAGENO - base) ? base + augend : MAX_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __maybe_unused __inline pgno_t
-pgno_sub(pgno_t base, pgno_t subtrahend) {
-  assert(base >= MIN_PAGENO);
-  return (subtrahend < base - MIN_PAGENO) ? base - subtrahend : MIN_PAGENO;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused bool
-is_powerof2(size_t x) {
-  return (x & (x - 1)) == 0;
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-floor_powerof2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return value & ~(granularity - 1);
-}
-
-MDBX_NOTHROW_CONST_FUNCTION static __always_inline __maybe_unused size_t
-ceil_powerof2(size_t value, size_t granularity) {
-  return floor_powerof2(value + granularity - 1, granularity);
-}
-
-/* Only a subset of the mdbx_env flags can be changed
- * at runtime. Changing other flags requires closing the
- * environment and re-opening it with the new flags. */
-#define ENV_CHANGEABLE_FLAGS                                                   \
-  (MDBX_SAFE_NOSYNC | MDBX_NOMETASYNC | MDBX_DEPRECATED_MAPASYNC |             \
-   MDBX_NOMEMINIT | MDBX_COALESCE | MDBX_PAGEPERTURB | MDBX_ACCEDE)
-#define ENV_CHANGELESS_FLAGS                                                   \
-  (MDBX_NOSUBDIR | MDBX_RDONLY | MDBX_WRITEMAP | MDBX_NOTLS | MDBX_NORDAHEAD | \
-   MDBX_LIFORECLAIM | MDBX_EXCLUSIVE)
-#define ENV_USABLE_FLAGS (ENV_CHANGEABLE_FLAGS | ENV_CHANGELESS_FLAGS)
-
-#if !defined(__cplusplus) || defined(__cpp_constexpr)
-static __maybe_unused void static_checks(void) {
-  STATIC_ASSERT_MSG(INT16_MAX - CORE_DBS == MDBX_MAX_DBI,
-                    "Oops, MDBX_MAX_DBI or CORE_DBS?");
-  STATIC_ASSERT_MSG((unsigned)(MDBX_DB_ACCEDE | MDBX_CREATE) ==
-                        ((DB_USABLE_FLAGS | DB_INTERNAL_FLAGS) &
-                         (ENV_USABLE_FLAGS | ENV_INTERNAL_FLAGS)),
-                    "Oops, some flags overlapped or wrong");
-  STATIC_ASSERT_MSG((ENV_INTERNAL_FLAGS & ENV_USABLE_FLAGS) == 0,
-                    "Oops, some flags overlapped or wrong");
-}
-#endif /* Disabled for MSVC 19.0 (VisualStudio 2015) */
-
-#ifdef __cplusplus
-}
-#endif
-
-#if defined(_WIN32) || defined(_WIN64)
-/*
- * POSIX getopt for Windows
- *
- * AT&T Public License
- *
- * Code given out at the 1985 UNIFORUM conference in Dallas.
- */
-
-/*----------------------------------------------------------------------------*/
-/* Microsoft compiler generates a lot of warning for self includes... */
-
-#ifdef _MSC_VER
-#pragma warning(push, 1)
-#pragma warning(disable : 4548) /* expression before comma has no effect;      \
-                                   expected expression with side - effect */
-#pragma warning(disable : 4530) /* C++ exception handler used, but unwind      \
-                                 * semantics are not enabled. Specify /EHsc */
-#pragma warning(disable : 4577) /* 'noexcept' used with no exception handling  \
-                                 * mode specified; termination on exception is \
-                                 * not guaranteed. Specify /EHsc */
-#if !defined(_CRT_SECURE_NO_WARNINGS)
-#define _CRT_SECURE_NO_WARNINGS
-#endif
-#endif /* _MSC_VER (warnings) */
-
-#include <stdio.h>
-#include <string.h>
-
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
-/*----------------------------------------------------------------------------*/
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-#ifndef EOF
-#define EOF (-1)
-#endif
-
-int optind = 1;
-int optopt;
-char *optarg;
-
-int getopt(int argc, char *const argv[], const char *opts) {
-  static int sp = 1;
-  int c;
-  const char *cp;
-
-  if (sp == 1) {
-    if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0')
-      return EOF;
-    else if (strcmp(argv[optind], "--") == 0) {
-      optind++;
-      return EOF;
-    }
-  }
-  optopt = c = argv[optind][sp];
-  if (c == ':' || (cp = strchr(opts, c)) == NULL) {
-    fprintf(stderr, "%s: %s -- %c\n", argv[0], "illegal option", c);
-    if (argv[optind][++sp] == '\0') {
-      optind++;
-      sp = 1;
-    }
-    return '?';
-  }
-  if (*++cp == ':') {
-    if (argv[optind][sp + 1] != '\0')
-      optarg = &argv[optind++][sp + 1];
-    else if (++optind >= argc) {
-      fprintf(stderr, "%s: %s -- %c\n", argv[0], "option requires an argument",
-              c);
-      sp = 1;
-      return '?';
-    } else
-      optarg = argv[optind++];
-    sp = 1;
-  } else {
-    if (argv[optind][++sp] == '\0') {
-      sp = 1;
-      optind++;
-    }
-    optarg = NULL;
-  }
-  return c;
-}
-
-static volatile BOOL user_break;
-static BOOL WINAPI ConsoleBreakHandlerRoutine(DWORD dwCtrlType) {
-  (void)dwCtrlType;
-  user_break = true;
-  return true;
-}
-
-#else /* WINDOWS */
-
-static volatile sig_atomic_t user_break;
-static void signal_handler(int sig) {
-  (void)sig;
-  user_break = 1;
-}
-
-#endif /* !WINDOWS */
-
-static void print_stat(MDBX_stat *ms) {
-  printf("  Pagesize: %u\n", ms->ms_psize);
-  printf("  Tree depth: %u\n", ms->ms_depth);
-  printf("  Branch pages: %" PRIu64 "\n", ms->ms_branch_pages);
-  printf("  Leaf pages: %" PRIu64 "\n", ms->ms_leaf_pages);
-  printf("  Overflow pages: %" PRIu64 "\n", ms->ms_overflow_pages);
-  printf("  Entries: %" PRIu64 "\n", ms->ms_entries);
-}
-
-static void usage(const char *prog) {
-  fprintf(stderr,
-          "usage: %s [-V] [-e] [-f[f[f]]] [-r[r]] [-a|-s name] dbpath\n"
-          "  -V\t\tprint version and exit\n"
-          "  -e\t\tshow whole DB info\n"
-          "  -f\t\tshow GC info\n"
-          "  -r\t\tshow readers\n"
-          "  -a\t\tprint stat of main DB and all subDBs\n"
-          "  \t\t(default) print stat of only the main DB\n"
-          "  -s name\tprint stat of only the named subDB\n",
-          prog);
-  exit(EXIT_FAILURE);
-}
-
-static int reader_list_func(void *ctx, int num, int slot, mdbx_pid_t pid,
-                            mdbx_tid_t thread, uint64_t txnid, uint64_t lag,
-                            size_t bytes_used, size_t bytes_retained) {
-  (void)ctx;
-  if (num == 1)
-    printf("Reader Table\n"
-           "   #\tslot\t%6s %*s %20s %10s %13s %13s\n",
-           "pid", (int)sizeof(size_t) * 2, "thread", "txnid", "lag", "used",
-           "retained");
-
-  printf(" %3d)\t[%d]\t%6" PRIdSIZE " %*" PRIxPTR, num, slot, (size_t)pid,
-         (int)sizeof(size_t) * 2, (uintptr_t)thread);
-  if (txnid)
-    printf(" %20" PRIu64 " %10" PRIu64 " %12.1fM %12.1fM\n", txnid, lag,
-           bytes_used / 1048576.0, bytes_retained / 1048576.0);
-  else
-    printf(" %20s %10s %13s %13s\n", "-", "0", "0", "0");
-
-  return user_break ? MDBX_RESULT_TRUE : MDBX_RESULT_FALSE;
-}
-
-const char *prog;
-static void error(const char *func, int rc) {
-  fprintf(stderr, "%s: %s() error %d %s\n", prog, func, rc, mdbx_strerror(rc));
-}
-
-int main(int argc, char *argv[]) {
-  int o, rc;
-  MDBX_env *env;
-  MDBX_txn *txn;
-  MDBX_dbi dbi;
-  MDBX_stat mst;
-  MDBX_envinfo mei;
-  prog = argv[0];
-  char *envname;
-  char *subname = nullptr;
-  int alldbs = 0, envinfo = 0, envflags = 0, freinfo = 0, rdrinfo = 0;
-
-  if (argc < 2)
-    usage(prog);
-
-  while ((o = getopt(argc, argv,
-                     "V"
-                     "a"
-                     "e"
-                     "f"
-                     "n"
-                     "r"
-                     "s:")) != EOF) {
-    switch (o) {
-    case 'V':
-      printf("mdbx_stat version %d.%d.%d.%d\n"
-             " - source: %s %s, commit %s, tree %s\n"
-             " - anchor: %s\n"
-             " - build: %s for %s by %s\n"
-             " - flags: %s\n"
-             " - options: %s\n",
-             mdbx_version.major, mdbx_version.minor, mdbx_version.release,
-             mdbx_version.revision, mdbx_version.git.describe,
-             mdbx_version.git.datetime, mdbx_version.git.commit,
-             mdbx_version.git.tree, mdbx_sourcery_anchor, mdbx_build.datetime,
-             mdbx_build.target, mdbx_build.compiler, mdbx_build.flags,
-             mdbx_build.options);
-      return EXIT_SUCCESS;
-    case 'a':
-      if (subname)
-        usage(prog);
-      alldbs++;
-      break;
-    case 'e':
-      envinfo++;
-      break;
-    case 'f':
-      freinfo++;
-      break;
-    case 'n':
-      envflags |= MDBX_NOSUBDIR;
-      break;
-    case 'r':
-      rdrinfo++;
-      break;
-    case 's':
-      if (alldbs)
-        usage(prog);
-      subname = optarg;
-      break;
-    default:
-      usage(prog);
-    }
-  }
-
-  if (optind != argc - 1)
-    usage(prog);
-
-#if defined(_WIN32) || defined(_WIN64)
-  SetConsoleCtrlHandler(ConsoleBreakHandlerRoutine, true);
-#else
-#ifdef SIGPIPE
-  signal(SIGPIPE, signal_handler);
-#endif
-#ifdef SIGHUP
-  signal(SIGHUP, signal_handler);
-#endif
-  signal(SIGINT, signal_handler);
-  signal(SIGTERM, signal_handler);
-#endif /* !WINDOWS */
-
-  envname = argv[optind];
-  envname = argv[optind];
-  printf("mdbx_stat %s (%s, T-%s)\nRunning for %s...\n",
-         mdbx_version.git.describe, mdbx_version.git.datetime,
-         mdbx_version.git.tree, envname);
-  fflush(nullptr);
-
-  rc = mdbx_env_create(&env);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_create", rc);
-    return EXIT_FAILURE;
-  }
-
-  if (alldbs || subname) {
-    rc = mdbx_env_set_maxdbs(env, 2);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_env_set_maxdbs", rc);
-      goto env_close;
-    }
-  }
-
-  rc = mdbx_env_open(env, envname, envflags | MDBX_RDONLY, 0664);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_env_open", rc);
-    goto env_close;
-  }
-
-  rc = mdbx_txn_begin(env, nullptr, MDBX_TXN_RDONLY, &txn);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_txn_begin", rc);
-    goto txn_abort;
-  }
-
-  if (envinfo || freinfo) {
-    rc = mdbx_env_info_ex(env, txn, &mei, sizeof(mei));
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_env_info_ex", rc);
-      goto txn_abort;
-    }
-  } else {
-    /* LY: zap warnings from gcc */
-    memset(&mei, 0, sizeof(mei));
-  }
-
-  if (envinfo) {
-    rc = mdbx_env_stat_ex(env, txn, &mst, sizeof(mst));
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_env_stat_ex", rc);
-      goto txn_abort;
-    }
-    printf("Environment Info\n");
-    printf("  Pagesize: %u\n", mst.ms_psize);
-    if (mei.mi_geo.lower != mei.mi_geo.upper) {
-      printf("  Dynamic datafile: %" PRIu64 "..%" PRIu64 " bytes (+%" PRIu64
-             "/-%" PRIu64 "), %" PRIu64 "..%" PRIu64 " pages (+%" PRIu64
-             "/-%" PRIu64 ")\n",
-             mei.mi_geo.lower, mei.mi_geo.upper, mei.mi_geo.grow,
-             mei.mi_geo.shrink, mei.mi_geo.lower / mst.ms_psize,
-             mei.mi_geo.upper / mst.ms_psize, mei.mi_geo.grow / mst.ms_psize,
-             mei.mi_geo.shrink / mst.ms_psize);
-      printf("  Current mapsize: %" PRIu64 " bytes, %" PRIu64 " pages \n",
-             mei.mi_mapsize, mei.mi_mapsize / mst.ms_psize);
-      printf("  Current datafile: %" PRIu64 " bytes, %" PRIu64 " pages\n",
-             mei.mi_geo.current, mei.mi_geo.current / mst.ms_psize);
-#if defined(_WIN32) || defined(_WIN64)
-      if (mei.mi_geo.shrink && mei.mi_geo.current != mei.mi_geo.upper)
-        printf("                    WARNING: Due Windows system limitations a "
-               "file couldn't\n                    be truncated while database "
-               "is opened. So, the size of\n                    database file "
-               "may by large than the database itself,\n                    "
-               "until it will be closed or reopened in read-write mode.\n");
-#endif
-    } else {
-      printf("  Fixed datafile: %" PRIu64 " bytes, %" PRIu64 " pages\n",
-             mei.mi_geo.current, mei.mi_geo.current / mst.ms_psize);
-    }
-    printf("  Last transaction ID: %" PRIu64 "\n", mei.mi_recent_txnid);
-    printf("  Latter reader transaction ID: %" PRIu64 " (%" PRIi64 ")\n",
-           mei.mi_latter_reader_txnid,
-           mei.mi_latter_reader_txnid - mei.mi_recent_txnid);
-    printf("  Max readers: %u\n", mei.mi_maxreaders);
-    printf("  Number of reader slots uses: %u\n", mei.mi_numreaders);
-  } else {
-    /* LY: zap warnings from gcc */
-    memset(&mst, 0, sizeof(mst));
-  }
-
-  if (rdrinfo) {
-    rc = mdbx_reader_list(env, reader_list_func, nullptr);
-    if (MDBX_IS_ERROR(rc)) {
-      error("mdbx_reader_list", rc);
-      goto txn_abort;
-    }
-    if (rc == MDBX_RESULT_TRUE)
-      printf("Reader Table is empty\n");
-    else if (rc == MDBX_SUCCESS && rdrinfo > 1) {
-      int dead;
-      rc = mdbx_reader_check(env, &dead);
-      if (MDBX_IS_ERROR(rc)) {
-        error("mdbx_reader_check", rc);
-        goto txn_abort;
-      }
-      if (rc == MDBX_RESULT_TRUE) {
-        printf("  %d stale readers cleared.\n", dead);
-        rc = mdbx_reader_list(env, reader_list_func, nullptr);
-        if (rc == MDBX_RESULT_TRUE)
-          printf("  Now Reader Table is empty\n");
-      } else
-        printf("  No stale readers.\n");
-    }
-    if (!(subname || alldbs || freinfo))
-      goto txn_abort;
-  }
-
-  if (freinfo) {
-    printf("Garbage Collection\n");
-    dbi = 0;
-    MDBX_cursor *cursor;
-    rc = mdbx_cursor_open(txn, dbi, &cursor);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_cursor_open", rc);
-      goto txn_abort;
-    }
-    rc = mdbx_dbi_stat(txn, dbi, &mst, sizeof(mst));
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_dbi_stat", rc);
-      goto txn_abort;
-    }
-    print_stat(&mst);
-
-    pgno_t pages = 0, *iptr;
-    pgno_t reclaimable = 0;
-    MDBX_val key, data;
-    while (MDBX_SUCCESS ==
-           (rc = mdbx_cursor_get(cursor, &key, &data, MDBX_NEXT))) {
-      if (user_break) {
-        rc = MDBX_EINTR;
-        break;
-      }
-      iptr = data.iov_base;
-      const pgno_t number = *iptr++;
-
-      pages += number;
-      if (envinfo && mei.mi_latter_reader_txnid > *(txnid_t *)key.iov_base)
-        reclaimable += number;
-
-      if (freinfo > 1) {
-        char *bad = "";
-        pgno_t prev =
-            MDBX_PNL_ASCENDING ? NUM_METAS - 1 : (pgno_t)mei.mi_last_pgno + 1;
-        pgno_t span = 1;
-        for (unsigned i = 0; i < number; ++i) {
-          pgno_t pg = iptr[i];
-          if (MDBX_PNL_DISORDERED(prev, pg))
-            bad = " [bad sequence]";
-          prev = pg;
-          while (i + span < number &&
-                 iptr[i + span] == (MDBX_PNL_ASCENDING ? pgno_add(pg, span)
-                                                       : pgno_sub(pg, span)))
-            ++span;
-        }
-        printf("    Transaction %" PRIaTXN ", %" PRIaPGNO
-               " pages, maxspan %" PRIaPGNO "%s\n",
-               *(txnid_t *)key.iov_base, number, span, bad);
-        if (freinfo > 2) {
-          for (unsigned i = 0; i < number; i += span) {
-            const pgno_t pg = iptr[i];
-            for (span = 1;
-                 i + span < number &&
-                 iptr[i + span] == (MDBX_PNL_ASCENDING ? pgno_add(pg, span)
-                                                       : pgno_sub(pg, span));
-                 ++span)
-              ;
-            if (span > 1)
-              printf("     %9" PRIaPGNO "[%" PRIaPGNO "]\n", pg, span);
-            else
-              printf("     %9" PRIaPGNO "\n", pg);
-          }
-        }
-      }
-    }
-    mdbx_cursor_close(cursor);
-    cursor = nullptr;
-
-    switch (rc) {
-    case MDBX_SUCCESS:
-    case MDBX_NOTFOUND:
-      break;
-    case MDBX_EINTR:
-      fprintf(stderr, "Interrupted by signal/user\n");
-      goto txn_abort;
-    default:
-      error("mdbx_cursor_get", rc);
-      goto txn_abort;
-    }
-
-    if (envinfo) {
-      uint64_t value = mei.mi_mapsize / mst.ms_psize;
-      double percent = value / 100.0;
-      printf("Page Usage\n");
-      printf("  Total: %" PRIu64 " 100%%\n", value);
-
-      value = mei.mi_geo.current / mst.ms_psize;
-      printf("  Backed: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value = mei.mi_last_pgno + 1;
-      printf("  Allocated: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value = mei.mi_mapsize / mst.ms_psize - (mei.mi_last_pgno + 1);
-      printf("  Remained: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value = mei.mi_last_pgno + 1 - pages;
-      printf("  Used: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value = pages;
-      printf("  GC: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value = pages - reclaimable;
-      printf("  Retained: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value = reclaimable;
-      printf("  Reclaimable: %" PRIu64 " %.1f%%\n", value, value / percent);
-
-      value =
-          mei.mi_mapsize / mst.ms_psize - (mei.mi_last_pgno + 1) + reclaimable;
-      printf("  Available: %" PRIu64 " %.1f%%\n", value, value / percent);
-    } else
-      printf("  GC: %" PRIaPGNO " pages\n", pages);
-  }
-
-  rc = mdbx_dbi_open(txn, subname, MDBX_DB_ACCEDE, &dbi);
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_dbi_open", rc);
-    goto txn_abort;
-  }
-  rc = mdbx_dbi_stat(txn, dbi, &mst, sizeof(mst));
-  if (unlikely(rc != MDBX_SUCCESS)) {
-    error("mdbx_dbi_stat", rc);
-    goto txn_abort;
-  }
-  printf("Status of %s\n", subname ? subname : "Main DB");
-  print_stat(&mst);
-
-  if (alldbs) {
-    MDBX_cursor *cursor;
-    rc = mdbx_cursor_open(txn, dbi, &cursor);
-    if (unlikely(rc != MDBX_SUCCESS)) {
-      error("mdbx_cursor_open", rc);
-      goto txn_abort;
-    }
-
-    MDBX_val key;
-    while (MDBX_SUCCESS ==
-           (rc = mdbx_cursor_get(cursor, &key, nullptr, MDBX_NEXT_NODUP))) {
-      MDBX_dbi subdbi;
-      if (memchr(key.iov_base, '\0', key.iov_len))
-        continue;
-      subname = mdbx_malloc(key.iov_len + 1);
-      memcpy(subname, key.iov_base, key.iov_len);
-      subname[key.iov_len] = '\0';
-      rc = mdbx_dbi_open(txn, subname, MDBX_DB_ACCEDE, &subdbi);
-      if (rc == MDBX_SUCCESS)
-        printf("Status of %s\n", subname);
-      mdbx_free(subname);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        if (rc == MDBX_INCOMPATIBLE)
-          continue;
-        error("mdbx_dbi_open", rc);
-        goto txn_abort;
-      }
-
-      rc = mdbx_dbi_stat(txn, subdbi, &mst, sizeof(mst));
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_dbi_stat", rc);
-        goto txn_abort;
-      }
-      print_stat(&mst);
-
-      rc = mdbx_dbi_close(env, subdbi);
-      if (unlikely(rc != MDBX_SUCCESS)) {
-        error("mdbx_dbi_close", rc);
-        goto txn_abort;
-      }
-    }
-    mdbx_cursor_close(cursor);
-    cursor = nullptr;
-  }
-
-  switch (rc) {
-  case MDBX_SUCCESS:
-  case MDBX_NOTFOUND:
-    break;
-  case MDBX_EINTR:
-    fprintf(stderr, "Interrupted by signal/user\n");
-    break;
-  default:
-    if (unlikely(rc != MDBX_SUCCESS))
-      error("mdbx_cursor_get", rc);
-  }
-
-  mdbx_dbi_close(env, dbi);
-txn_abort:
-  mdbx_txn_abort(txn);
-env_close:
-  mdbx_env_close(env);
-
-  return rc ? EXIT_FAILURE : EXIT_SUCCESS;
-}
diff --git a/plugins/Dbx_mdbx/src/libmdbx/ntdll.def b/plugins/Dbx_mdbx/src/libmdbx/ntdll.def
deleted file mode 100644
index f974ea6380..0000000000
--- a/plugins/Dbx_mdbx/src/libmdbx/ntdll.def
+++ /dev/null
@@ -1,1246 +0,0 @@
-LIBRARY ntdll
-EXPORTS
-CsrAllocateCaptureBuffer
-CsrAllocateMessagePointer
-CsrCaptureMessageBuffer
-CsrCaptureMessageMultiUnicodeStringsInPlace
-CsrCaptureMessageString
-CsrCaptureTimeout
-CsrClientCallServer
-CsrClientConnectToServer
-CsrFreeCaptureBuffer
-CsrGetProcessId
-CsrIdentifyAlertableThread
-CsrSetPriorityClass
-DbgBreakPoint
-DbgPrint
-DbgPrintEx
-DbgPrintReturnControlC
-DbgPrompt
-DbgQueryDebugFilterState
-DbgSetDebugFilterState
-DbgUiConnectToDbg
-DbgUiContinue
-DbgUiConvertStateChangeStructure
-DbgUiDebugActiveProcess
-DbgUiGetThreadDebugObject
-DbgUiIssueRemoteBreakin
-DbgUiRemoteBreakin
-DbgUiSetThreadDebugObject
-DbgUiStopDebugging
-DbgUiWaitStateChange
-DbgUserBreakPoint
-KiRaiseUserExceptionDispatcher
-KiUserApcDispatcher
-KiUserCallbackDispatcher
-KiUserExceptionDispatcher
-LdrAccessResource
-LdrAddRefDll
-LdrDisableThreadCalloutsForDll
-LdrEnumResources
-LdrEnumerateLoadedModules
-LdrFindEntryForAddress
-LdrFindResourceDirectory_U
-LdrFindResourceEx_U
-LdrFindResource_U
-LdrFlushAlternateResourceModules
-LdrGetDllHandle
-LdrGetDllHandleEx
-LdrGetProcedureAddress
-LdrInitShimEngineDynamic
-LdrInitializeThunk
-LdrLoadAlternateResourceModule
-LdrLoadDll
-LdrLockLoaderLock
-LdrProcessRelocationBlock
-LdrQueryImageFileExecutionOptions
-LdrQueryProcessModuleInformation
-LdrSetAppCompatDllRedirectionCallback
-LdrSetDllManifestProber
-LdrShutdownProcess
-LdrShutdownThread
-LdrUnloadAlternateResourceModule
-LdrUnloadDll
-LdrUnlockLoaderLock
-LdrVerifyImageMatchesChecksum
-NlsAnsiCodePage
-NlsMbCodePageTag
-NlsMbOemCodePageTag
-NtAcceptConnectPort
-NtAccessCheck
-NtAccessCheckAndAuditAlarm
-NtAccessCheckByType
-NtAccessCheckByTypeAndAuditAlarm
-NtAccessCheckByTypeResultList
-NtAccessCheckByTypeResultListAndAuditAlarm
-NtAccessCheckByTypeResultListAndAuditAlarmByHandle
-NtAddAtom
-NtAddBootEntry
-NtAdjustGroupsToken
-NtAdjustPrivilegesToken
-NtAlertResumeThread
-NtAlertThread
-NtAllocateLocallyUniqueId
-NtAllocateUserPhysicalPages
-NtAllocateUuids
-NtAllocateVirtualMemory
-NtAreMappedFilesTheSame
-NtAssignProcessToJobObject
-NtCallbackReturn
-NtCancelIoFile
-NtCancelTimer
-NtClearEvent
-NtClose
-NtCloseObjectAuditAlarm
-NtCompactKeys
-NtCompareTokens
-NtCompleteConnectPort
-NtCompressKey
-NtConnectPort
-NtContinue
-NtCreateDebugObject
-NtCreateDirectoryObject
-NtCreateEvent
-NtCreateEventPair
-NtCreateFile
-NtCreateIoCompletion
-NtCreateJobObject
-NtCreateJobSet
-NtCreateKey
-NtCreateKeyedEvent
-NtCreateMailslotFile
-NtCreateMutant
-NtCreateNamedPipeFile
-NtCreatePagingFile
-NtCreatePort
-NtCreateProcess
-NtCreateProcessEx
-NtCreateProfile
-NtCreateSection
-NtCreateSemaphore
-NtCreateSymbolicLinkObject
-NtCreateThread
-NtCreateTimer
-NtCreateToken
-NtCreateWaitablePort
-NtDebugActiveProcess
-NtDebugContinue
-NtDelayExecution
-NtDeleteAtom
-NtDeleteBootEntry
-NtDeleteFile
-NtDeleteKey
-NtDeleteObjectAuditAlarm
-NtDeleteValueKey
-NtDeviceIoControlFile
-NtDisplayString
-NtDuplicateObject
-NtDuplicateToken
-NtEnumerateBootEntries
-NtEnumerateKey
-NtEnumerateSystemEnvironmentValuesEx
-NtEnumerateValueKey
-NtExtendSection
-NtFilterToken
-NtFindAtom
-NtFlushBuffersFile
-NtFlushInstructionCache
-NtFlushKey
-NtFlushVirtualMemory
-NtFlushWriteBuffer
-NtFreeUserPhysicalPages
-NtFreeVirtualMemory
-NtFsControlFile
-NtGetContextThread
-NtGetDevicePowerState
-NtGetWriteWatch
-NtImpersonateAnonymousToken
-NtImpersonateClientOfPort
-NtImpersonateThread
-NtInitializeRegistry
-NtInitiatePowerAction
-NtIsProcessInJob
-NtIsSystemResumeAutomatic
-NtListenPort
-NtLoadDriver
-NtLoadKey
-NtLoadKey2
-NtLockFile
-NtLockProductActivationKeys
-NtLockRegistryKey
-NtLockVirtualMemory
-NtMakePermanentObject
-NtMakeTemporaryObject
-NtMapUserPhysicalPages
-NtMapUserPhysicalPagesScatter
-NtMapViewOfSection
-NtModifyBootEntry
-NtNotifyChangeDirectoryFile
-NtNotifyChangeKey
-NtNotifyChangeMultipleKeys
-NtOpenDirectoryObject
-NtOpenEvent
-NtOpenEventPair
-NtOpenFile
-NtOpenIoCompletion
-NtOpenJobObject
-NtOpenKey
-NtOpenKeyedEvent
-NtOpenMutant
-NtOpenObjectAuditAlarm
-NtOpenProcess
-NtOpenProcessToken
-NtOpenProcessTokenEx
-NtOpenSection
-NtOpenSemaphore
-NtOpenSymbolicLinkObject
-NtOpenThread
-NtOpenThreadToken
-NtOpenThreadTokenEx
-NtOpenTimer
-NtPlugPlayControl
-NtPowerInformation
-NtPrivilegeCheck
-NtPrivilegeObjectAuditAlarm
-NtPrivilegedServiceAuditAlarm
-NtProtectVirtualMemory
-NtPulseEvent
-NtQueryAttributesFile
-NtQueryBootEntryOrder
-NtQueryBootOptions
-NtQueryDebugFilterState
-NtQueryDefaultLocale
-NtQueryDefaultUILanguage
-NtQueryDirectoryFile
-NtQueryDirectoryObject
-NtQueryEaFile
-NtQueryEvent
-NtQueryFullAttributesFile
-NtQueryInformationAtom
-NtQueryInformationFile
-NtQueryInformationJobObject
-NtQueryInformationPort
-NtQueryInformationProcess
-NtQueryInformationThread
-NtQueryInformationToken
-NtQueryInstallUILanguage
-NtQueryIntervalProfile
-NtQueryIoCompletion
-NtQueryKey
-NtQueryMultipleValueKey
-NtQueryMutant
-NtQueryObject
-NtQueryOpenSubKeys
-NtQueryPerformanceCounter
-NtQueryPortInformationProcess
-NtQueryQuotaInformationFile
-NtQuerySection
-NtQuerySecurityObject
-NtQuerySemaphore
-NtQuerySymbolicLinkObject
-NtQuerySystemEnvironmentValue
-NtQuerySystemEnvironmentValueEx
-NtQuerySystemInformation
-NtQuerySystemTime
-NtQueryTimer
-NtQueryTimerResolution
-NtQueryValueKey
-NtQueryVirtualMemory
-NtQueryVolumeInformationFile
-NtQueueApcThread
-NtRaiseException
-NtRaiseHardError
-NtReadFile
-NtReadFileScatter
-NtReadRequestData
-NtReadVirtualMemory
-NtRegisterThreadTerminatePort
-NtReleaseKeyedEvent
-NtReleaseMutant
-NtReleaseSemaphore
-NtRemoveIoCompletion
-NtRemoveProcessDebug
-NtRenameKey
-NtReplaceKey
-NtReplyPort
-NtReplyWaitReceivePort
-NtReplyWaitReceivePortEx
-NtReplyWaitReplyPort
-NtRequestPort
-NtRequestWaitReplyPort
-NtResetEvent
-NtResetWriteWatch
-NtRestoreKey
-NtResumeProcess
-NtResumeThread
-NtSaveKey
-NtSaveKeyEx
-NtSaveMergedKeys
-NtSecureConnectPort
-NtSetBootEntryOrder
-NtSetBootOptions
-NtSetContextThread
-NtSetDebugFilterState
-NtSetDefaultHardErrorPort
-NtSetDefaultLocale
-NtSetDefaultUILanguage
-NtSetEaFile
-NtSetEvent
-NtSetEventBoostPriority
-NtSetHighEventPair
-NtSetHighWaitLowEventPair
-NtSetInformationDebugObject
-NtSetInformationFile
-NtSetInformationJobObject
-NtSetInformationKey
-NtSetInformationObject
-NtSetInformationProcess
-NtSetInformationThread
-NtSetInformationToken
-NtSetIntervalProfile
-NtSetIoCompletion
-NtSetLdtEntries
-NtSetLowEventPair
-NtSetLowWaitHighEventPair
-NtSetQuotaInformationFile
-NtSetSecurityObject
-NtSetSystemEnvironmentValue
-NtSetSystemEnvironmentValueEx
-NtSetSystemInformation
-NtSetSystemPowerState
-NtSetSystemTime
-NtSetThreadExecutionState
-NtSetTimer
-NtSetTimerResolution
-NtSetUuidSeed
-NtSetValueKey
-NtSetVolumeInformationFile
-NtShutdownSystem
-NtSignalAndWaitForSingleObject
-NtStartProfile
-NtStopProfile
-NtSuspendProcess
-NtSuspendThread
-NtSystemDebugControl
-NtTerminateJobObject
-NtTerminateProcess
-NtTerminateThread
-NtTestAlert
-NtTraceEvent
-NtTranslateFilePath
-NtUnloadDriver
-NtUnloadKey
-NtUnloadKeyEx
-NtUnlockFile
-NtUnlockVirtualMemory
-NtUnmapViewOfSection
-NtVdmControl
-NtWaitForDebugEvent
-NtWaitForKeyedEvent
-NtWaitForMultipleObjects
-NtWaitForSingleObject
-NtWaitHighEventPair
-NtWaitLowEventPair
-NtWriteFile
-NtWriteFileGather
-NtWriteRequestData
-NtWriteVirtualMemory
-NtYieldExecution
-PfxFindPrefix
-PfxInitialize
-PfxInsertPrefix
-PfxRemovePrefix
-RtlAbortRXact
-RtlAbsoluteToSelfRelativeSD
-RtlAcquirePebLock
-RtlAcquireResourceExclusive
-RtlAcquireResourceShared
-RtlActivateActivationContext
-RtlActivateActivationContextEx
-RtlActivateActivationContextUnsafeFast
-RtlAddAccessAllowedAce
-RtlAddAccessAllowedAceEx
-RtlAddAccessAllowedObjectAce
-RtlAddAccessDeniedAce
-RtlAddAccessDeniedAceEx
-RtlAddAccessDeniedObjectAce
-RtlAddAce
-RtlAddActionToRXact
-RtlAddAtomToAtomTable
-RtlAddAttributeActionToRXact
-RtlAddAuditAccessAce
-RtlAddAuditAccessAceEx
-RtlAddAuditAccessObjectAce
-RtlAddCompoundAce
-RtlAddRefActivationContext
-RtlAddRefMemoryStream
-RtlAddVectoredExceptionHandler
-RtlAddressInSectionTable
-RtlAdjustPrivilege
-RtlAllocateAndInitializeSid
-RtlAllocateHandle
-RtlAllocateHeap
-RtlAnsiCharToUnicodeChar
-RtlAnsiStringToUnicodeSize
-RtlAnsiStringToUnicodeString
-RtlAppendAsciizToString
-RtlAppendPathElement
-RtlAppendStringToString
-RtlAppendUnicodeStringToString
-RtlAppendUnicodeToString
-RtlApplicationVerifierStop
-RtlApplyRXact
-RtlApplyRXactNoFlush
-RtlAreAllAccessesGranted
-RtlAreAnyAccessesGranted
-RtlAreBitsClear
-RtlAreBitsSet
-RtlAssert
-RtlCancelTimer
-RtlCaptureContext
-RtlCaptureStackBackTrace
-RtlCharToInteger
-RtlCheckForOrphanedCriticalSections
-RtlCheckRegistryKey
-RtlClearAllBits
-RtlClearBits
-RtlCloneMemoryStream
-RtlCommitMemoryStream
-RtlCompactHeap
-RtlCompareMemory
-RtlCompareMemoryUlong
-RtlCompareString
-RtlCompareUnicodeString
-RtlCompressBuffer
-RtlComputeCrc32
-RtlComputeImportTableHash
-RtlComputePrivatizedDllName_U
-RtlConsoleMultiByteToUnicodeN
-RtlConvertExclusiveToShared
-RtlConvertSharedToExclusive
-RtlConvertSidToUnicodeString
-RtlConvertToAutoInheritSecurityObject
-RtlCopyLuid
-RtlCopyLuidAndAttributesArray
-RtlCopyMemoryStreamTo
-RtlCopyOutOfProcessMemoryStreamTo
-RtlCopySecurityDescriptor
-RtlCopySid
-RtlCopySidAndAttributesArray
-RtlCopyString
-RtlCopyUnicodeString
-RtlCreateAcl
-RtlCreateActivationContext
-RtlCreateAndSetSD
-RtlCreateAtomTable
-RtlCreateBootStatusDataFile
-RtlCreateEnvironment
-RtlCreateHeap
-RtlCreateProcessParameters
-RtlCreateQueryDebugBuffer
-RtlCreateRegistryKey
-RtlCreateSecurityDescriptor
-RtlCreateServiceSid
-RtlCreateSystemVolumeInformationFolder
-RtlCreateTagHeap
-RtlCreateTimer
-RtlCreateTimerQueue
-RtlCreateUnicodeString
-RtlCreateUnicodeStringFromAsciiz
-RtlCreateUserProcess
-RtlCreateUserSecurityObject
-RtlCreateUserThread
-RtlCustomCPToUnicodeN
-RtlCutoverTimeToSystemTime
-RtlDeNormalizeProcessParams
-RtlDeactivateActivationContext
-RtlDeactivateActivationContextUnsafeFast
-RtlDebugPrintTimes
-RtlDecodePointer
-RtlDecodeSystemPointer
-RtlDecompressBuffer
-RtlDecompressFragment
-RtlDefaultNpAcl
-RtlDelete
-RtlDeleteAce
-RtlDeleteAtomFromAtomTable
-RtlDeleteCriticalSection
-RtlDeleteElementGenericTable
-RtlDeleteElementGenericTableAvl
-RtlDeleteNoSplay
-RtlDeleteRegistryValue
-RtlDeleteResource
-RtlDeleteSecurityObject
-RtlDeleteTimer
-RtlDeleteTimerQueue
-RtlDeleteTimerQueueEx
-RtlDeregisterWait
-RtlDeregisterWaitEx
-RtlDestroyAtomTable
-RtlDestroyEnvironment
-RtlDestroyHandleTable
-RtlDestroyHeap
-RtlDestroyProcessParameters
-RtlDestroyQueryDebugBuffer
-RtlDetermineDosPathNameType_U
-RtlDllShutdownInProgress
-RtlDnsHostNameToComputerName
-RtlDoesFileExists_U
-RtlDosApplyFileIsolationRedirection_Ustr
-RtlDosPathNameToNtPathName_U
-RtlDosSearchPath_U
-RtlDosSearchPath_Ustr
-RtlDowncaseUnicodeChar
-RtlDowncaseUnicodeString
-RtlDumpResource
-RtlDuplicateUnicodeString
-RtlEmptyAtomTable
-RtlEnableEarlyCriticalSectionEventCreation
-RtlEncodePointer
-RtlEncodeSystemPointer
-RtlEnterCriticalSection
-RtlEnumProcessHeaps
-RtlEnumerateGenericTable
-RtlEnumerateGenericTableAvl
-RtlEnumerateGenericTableLikeADirectory
-RtlEnumerateGenericTableWithoutSplaying
-RtlEnumerateGenericTableWithoutSplayingAvl
-RtlEqualComputerName
-RtlEqualDomainName
-RtlEqualLuid
-RtlEqualPrefixSid
-RtlEqualSid
-RtlEqualString
-RtlEqualUnicodeString
-RtlEraseUnicodeString
-RtlExitUserThread
-RtlExpandEnvironmentStrings_U
-RtlFillMemory
-RtlFinalReleaseOutOfProcessMemoryStream
-RtlFindActivationContextSectionGuid
-RtlFindActivationContextSectionString
-RtlFindCharInUnicodeString
-RtlFindClearBits
-RtlFindClearBitsAndSet
-RtlFindClearRuns
-RtlFindLastBackwardRunClear
-RtlFindLeastSignificantBit
-RtlFindLongestRunClear
-RtlFindMessage
-RtlFindMostSignificantBit
-RtlFindNextForwardRunClear
-RtlFindSetBits
-RtlFindSetBitsAndClear
-RtlFirstEntrySList
-RtlFirstFreeAce
-RtlFlushSecureMemoryCache
-RtlFormatCurrentUserKeyPath
-RtlFormatMessage
-RtlFreeAnsiString
-RtlFreeHandle
-RtlFreeHeap
-RtlFreeOemString
-RtlFreeSid
-RtlFreeThreadActivationContextStack
-RtlFreeUnicodeString
-RtlGUIDFromString
-RtlGenerate8dot3Name
-RtlGetAce
-RtlGetActiveActivationContext
-RtlGetCallersAddress
-RtlGetCompressionWorkSpaceSize
-RtlGetControlSecurityDescriptor
-RtlGetCurrentDirectory_U
-RtlGetCurrentPeb
-RtlGetDaclSecurityDescriptor
-RtlGetElementGenericTable
-RtlGetElementGenericTableAvl
-RtlGetFrame
-RtlGetFullPathName_U
-RtlGetGroupSecurityDescriptor
-RtlGetLastNtStatus
-RtlGetLastWin32Error
-RtlGetLengthWithoutLastFullDosOrNtPathElement
-RtlGetLengthWithoutTrailingPathSeperators
-RtlGetLongestNtPathLength
-RtlGetNativeSystemInformation
-RtlGetNtGlobalFlags
-RtlGetNtProductType
-RtlGetNtVersionNumbers
-RtlGetOwnerSecurityDescriptor
-RtlGetProcessHeaps
-RtlGetSaclSecurityDescriptor
-RtlGetSecurityDescriptorRMControl
-RtlGetSetBootStatusData
-RtlGetUnloadEventTrace
-RtlGetUserInfoHeap
-RtlGetVersion
-RtlHashUnicodeString
-RtlIdentifierAuthoritySid
-RtlImageDirectoryEntryToData
-RtlImageNtHeader
-RtlImageRvaToSection
-RtlImageRvaToVa
-RtlImpersonateSelf
-RtlInitAnsiString
-RtlInitCodePageTable
-RtlInitMemoryStream
-RtlInitNlsTables
-RtlInitOutOfProcessMemoryStream
-RtlInitString
-RtlInitUnicodeString
-RtlInitUnicodeStringEx
-RtlInitializeAtomPackage
-RtlInitializeBitMap
-RtlInitializeContext
-RtlInitializeCriticalSection
-RtlInitializeCriticalSectionAndSpinCount
-RtlInitializeGenericTable
-RtlInitializeGenericTableAvl
-RtlInitializeHandleTable
-RtlInitializeRXact
-RtlInitializeResource
-RtlInitializeSListHead
-RtlInitializeSid
-RtlInsertElementGenericTable
-RtlInsertElementGenericTableAvl
-RtlInt64ToUnicodeString
-RtlIntegerToChar
-RtlIntegerToUnicodeString
-RtlInterlockedFlushSList
-RtlInterlockedPopEntrySList
-RtlInterlockedPushEntrySList
-RtlInterlockedPushListSList
-RtlIpv4AddressToStringA
-RtlIpv4AddressToStringExA
-RtlIpv4AddressToStringExW
-RtlIpv4AddressToStringW
-RtlIpv4StringToAddressA
-RtlIpv4StringToAddressExA
-RtlIpv4StringToAddressExW
-RtlIpv4StringToAddressW
-RtlIpv6AddressToStringA
-RtlIpv6AddressToStringExA
-RtlIpv6AddressToStringExW
-RtlIpv6AddressToStringW
-RtlIpv6StringToAddressA
-RtlIpv6StringToAddressExA
-RtlIpv6StringToAddressExW
-RtlIpv6StringToAddressW
-RtlIsActivationContextActive
-RtlIsDosDeviceName_U
-RtlIsGenericTableEmpty
-RtlIsGenericTableEmptyAvl
-RtlIsNameLegalDOS8Dot3
-RtlIsTextUnicode
-RtlIsThreadWithinLoaderCallout
-RtlIsValidHandle
-RtlIsValidIndexHandle
-RtlLargeIntegerToChar
-RtlLeaveCriticalSection
-RtlLengthRequiredSid
-RtlLengthSecurityDescriptor
-RtlLengthSid
-RtlLocalTimeToSystemTime
-RtlLockBootStatusData
-RtlLockHeap
-RtlLockMemoryStreamRegion
-RtlLogStackBackTrace
-RtlLookupAtomInAtomTable
-RtlLookupElementGenericTable
-RtlLookupElementGenericTableAvl
-RtlMakeSelfRelativeSD
-RtlMapGenericMask
-RtlMapSecurityErrorToNtStatus
-RtlMoveMemory
-RtlMultiAppendUnicodeStringBuffer
-RtlMultiByteToUnicodeN
-RtlMultiByteToUnicodeSize
-RtlNewInstanceSecurityObject
-RtlNewSecurityGrantedAccess
-RtlNewSecurityObject
-RtlNewSecurityObjectEx
-RtlNewSecurityObjectWithMultipleInheritance
-RtlNormalizeProcessParams
-RtlNtPathNameToDosPathName
-RtlNtStatusToDosError
-RtlNtStatusToDosErrorNoTeb
-RtlNumberGenericTableElements
-RtlNumberGenericTableElementsAvl
-RtlNumberOfClearBits
-RtlNumberOfSetBits
-RtlOemStringToUnicodeSize
-RtlOemStringToUnicodeString
-RtlOemToUnicodeN
-RtlOpenCurrentUser
-RtlPcToFileHeader
-RtlPinAtomInAtomTable
-RtlPopFrame
-RtlPrefixString
-RtlPrefixUnicodeString
-RtlProtectHeap
-RtlPushFrame
-RtlQueryAtomInAtomTable
-RtlQueryDepthSList
-RtlQueryEnvironmentVariable_U
-RtlQueryHeapInformation
-RtlQueryInformationAcl
-RtlQueryInformationActivationContext
-RtlQueryInformationActiveActivationContext
-RtlQueryInterfaceMemoryStream
-RtlQueryProcessBackTraceInformation
-RtlQueryProcessDebugInformation
-RtlQueryProcessHeapInformation
-RtlQueryProcessLockInformation
-RtlQueryRegistryValues
-RtlQuerySecurityObject
-RtlQueryTagHeap
-RtlQueryTimeZoneInformation
-RtlQueueApcWow64Thread
-RtlQueueWorkItem
-RtlRaiseException
-RtlRaiseStatus
-RtlRandom
-RtlRandomEx
-RtlReAllocateHeap
-RtlReadMemoryStream
-RtlReadOutOfProcessMemoryStream
-RtlRealPredecessor
-RtlRealSuccessor
-RtlRegisterSecureMemoryCacheCallback
-RtlRegisterWait
-RtlReleaseActivationContext
-RtlReleaseMemoryStream
-RtlReleasePebLock
-RtlReleaseResource
-RtlRemoteCall
-RtlRemoveVectoredExceptionHandler
-RtlResetRtlTranslations
-RtlRestoreLastWin32Error
-RtlRevertMemoryStream
-RtlRunDecodeUnicodeString
-RtlRunEncodeUnicodeString
-RtlSecondsSince1970ToTime
-RtlSecondsSince1980ToTime
-RtlSeekMemoryStream
-RtlSelfRelativeToAbsoluteSD
-RtlSelfRelativeToAbsoluteSD2
-RtlSetAllBits
-RtlSetAttributesSecurityDescriptor
-RtlSetBits
-RtlSetControlSecurityDescriptor
-RtlSetCriticalSectionSpinCount
-RtlSetCurrentDirectory_U
-RtlSetCurrentEnvironment
-RtlSetDaclSecurityDescriptor
-RtlSetEnvironmentVariable
-RtlSetGroupSecurityDescriptor
-RtlSetHeapInformation
-RtlSetInformationAcl
-RtlSetIoCompletionCallback
-RtlSetLastWin32Error
-RtlSetLastWin32ErrorAndNtStatusFromNtStatus
-RtlSetMemoryStreamSize
-RtlSetOwnerSecurityDescriptor
-RtlSetProcessIsCritical
-RtlSetSaclSecurityDescriptor
-RtlSetSecurityDescriptorRMControl
-RtlSetSecurityObject
-RtlSetSecurityObjectEx
-RtlSetThreadIsCritical
-RtlSetThreadPoolStartFunc
-RtlSetTimeZoneInformation
-RtlSetTimer
-RtlSetUserFlagsHeap
-RtlSetUserValueHeap
-RtlSizeHeap
-RtlSplay
-RtlStartRXact
-RtlStatMemoryStream
-RtlStringFromGUID
-RtlSubAuthorityCountSid
-RtlSubAuthoritySid
-RtlSubtreePredecessor
-RtlSubtreeSuccessor
-RtlSystemTimeToLocalTime
-RtlTimeFieldsToTime
-RtlTimeToElapsedTimeFields
-RtlTimeToSecondsSince1970
-RtlTimeToSecondsSince1980
-RtlTimeToTimeFields
-RtlTraceDatabaseAdd
-RtlTraceDatabaseCreate
-RtlTraceDatabaseDestroy
-RtlTraceDatabaseEnumerate
-RtlTraceDatabaseFind
-RtlTraceDatabaseLock
-RtlTraceDatabaseUnlock
-RtlTraceDatabaseValidate
-RtlTryEnterCriticalSection
-RtlUnhandledExceptionFilter
-RtlUnhandledExceptionFilter2
-RtlUnicodeStringToAnsiSize
-RtlUnicodeStringToAnsiString
-RtlUnicodeStringToCountedOemString
-RtlUnicodeStringToInteger
-RtlUnicodeStringToOemSize
-RtlUnicodeStringToOemString
-RtlUnicodeToCustomCPN
-RtlUnicodeToMultiByteN
-RtlUnicodeToMultiByteSize
-RtlUnicodeToOemN
-RtlUniform
-RtlUnlockBootStatusData
-RtlUnlockHeap
-RtlUnlockMemoryStreamRegion
-RtlUnwind
-RtlUpcaseUnicodeChar
-RtlUpcaseUnicodeString
-RtlUpcaseUnicodeStringToAnsiString
-RtlUpcaseUnicodeStringToCountedOemString
-RtlUpcaseUnicodeStringToOemString
-RtlUpcaseUnicodeToCustomCPN
-RtlUpcaseUnicodeToMultiByteN
-RtlUpcaseUnicodeToOemN
-RtlUpdateTimer
-RtlUpperChar
-RtlUpperString
-RtlValidAcl
-RtlValidRelativeSecurityDescriptor
-RtlValidSecurityDescriptor
-RtlValidSid
-RtlValidateHeap
-RtlValidateProcessHeaps
-RtlValidateUnicodeString
-RtlVerifyVersionInfo
-RtlWalkFrameChain
-RtlWalkHeap
-RtlWriteMemoryStream
-RtlWriteRegistryValue
-RtlZeroHeap
-RtlZeroMemory
-RtlZombifyActivationContext
-RtlpApplyLengthFunction
-RtlpEnsureBufferSize
-RtlpNotOwnerCriticalSection
-RtlpNtCreateKey
-RtlpNtEnumerateSubKey
-RtlpNtMakeTemporaryKey
-RtlpNtOpenKey
-RtlpNtQueryValueKey
-RtlpNtSetValueKey
-RtlpUnWaitCriticalSection
-RtlpWaitForCriticalSection
-RtlxAnsiStringToUnicodeSize
-RtlxOemStringToUnicodeSize
-RtlxUnicodeStringToAnsiSize
-RtlxUnicodeStringToOemSize
-VerSetConditionMask
-ZwAcceptConnectPort
-ZwAccessCheck
-ZwAccessCheckAndAuditAlarm
-ZwAccessCheckByType
-ZwAccessCheckByTypeAndAuditAlarm
-ZwAccessCheckByTypeResultList
-ZwAccessCheckByTypeResultListAndAuditAlarm
-ZwAccessCheckByTypeResultListAndAuditAlarmByHandle
-ZwAddAtom
-ZwAddBootEntry
-ZwAdjustGroupsToken
-ZwAdjustPrivilegesToken
-ZwAlertResumeThread
-ZwAlertThread
-ZwAllocateLocallyUniqueId
-ZwAllocateUserPhysicalPages
-ZwAllocateUuids
-ZwAllocateVirtualMemory
-ZwAreMappedFilesTheSame
-ZwAssignProcessToJobObject
-ZwCallbackReturn
-ZwCancelIoFile
-ZwCancelTimer
-ZwClearEvent
-ZwClose
-ZwCloseObjectAuditAlarm
-ZwCompactKeys
-ZwCompareTokens
-ZwCompleteConnectPort
-ZwCompressKey
-ZwConnectPort
-ZwContinue
-ZwCreateDebugObject
-ZwCreateDirectoryObject
-ZwCreateEvent
-ZwCreateEventPair
-ZwCreateFile
-ZwCreateIoCompletion
-ZwCreateJobObject
-ZwCreateJobSet
-ZwCreateKey
-ZwCreateKeyedEvent
-ZwCreateMailslotFile
-ZwCreateMutant
-ZwCreateNamedPipeFile
-ZwCreatePagingFile
-ZwCreatePort
-ZwCreateProcess
-ZwCreateProcessEx
-ZwCreateProfile
-ZwCreateSection
-ZwCreateSemaphore
-ZwCreateSymbolicLinkObject
-ZwCreateThread
-ZwCreateTimer
-ZwCreateToken
-ZwCreateWaitablePort
-ZwDebugActiveProcess
-ZwDebugContinue
-ZwDelayExecution
-ZwDeleteAtom
-ZwDeleteBootEntry
-ZwDeleteFile
-ZwDeleteKey
-ZwDeleteObjectAuditAlarm
-ZwDeleteValueKey
-ZwDeviceIoControlFile
-ZwDisplayString
-ZwDuplicateObject
-ZwDuplicateToken
-ZwEnumerateBootEntries
-ZwEnumerateKey
-ZwEnumerateSystemEnvironmentValuesEx
-ZwEnumerateValueKey
-ZwExtendSection
-ZwFilterToken
-ZwFindAtom
-ZwFlushBuffersFile
-ZwFlushInstructionCache
-ZwFlushKey
-ZwFlushVirtualMemory
-ZwFlushWriteBuffer
-ZwFreeUserPhysicalPages
-ZwFreeVirtualMemory
-ZwFsControlFile
-ZwGetContextThread
-ZwGetDevicePowerState
-ZwGetWriteWatch
-ZwImpersonateAnonymousToken
-ZwImpersonateClientOfPort
-ZwImpersonateThread
-ZwInitializeRegistry
-ZwInitiatePowerAction
-ZwIsProcessInJob
-ZwIsSystemResumeAutomatic
-ZwListenPort
-ZwLoadDriver
-ZwLoadKey
-ZwLoadKey2
-ZwLockFile
-ZwLockProductActivationKeys
-ZwLockRegistryKey
-ZwLockVirtualMemory
-ZwMakePermanentObject
-ZwMakeTemporaryObject
-ZwMapUserPhysicalPages
-ZwMapUserPhysicalPagesScatter
-ZwMapViewOfSection
-ZwModifyBootEntry
-ZwNotifyChangeDirectoryFile
-ZwNotifyChangeKey
-ZwNotifyChangeMultipleKeys
-ZwOpenDirectoryObject
-ZwOpenEvent
-ZwOpenEventPair
-ZwOpenFile
-ZwOpenIoCompletion
-ZwOpenJobObject
-ZwOpenKey
-ZwOpenKeyedEvent
-ZwOpenMutant
-ZwOpenObjectAuditAlarm
-ZwOpenProcess
-ZwOpenProcessToken
-ZwOpenProcessTokenEx
-ZwOpenSection
-ZwOpenSemaphore
-ZwOpenSymbolicLinkObject
-ZwOpenThread
-ZwOpenThreadToken
-ZwOpenThreadTokenEx
-ZwOpenTimer
-ZwPlugPlayControl
-ZwPowerInformation
-ZwPrivilegeCheck
-ZwPrivilegeObjectAuditAlarm
-ZwPrivilegedServiceAuditAlarm
-ZwProtectVirtualMemory
-ZwPulseEvent
-ZwQueryAttributesFile
-ZwQueryBootEntryOrder
-ZwQueryBootOptions
-ZwQueryDebugFilterState
-ZwQueryDefaultLocale
-ZwQueryDefaultUILanguage
-ZwQueryDirectoryFile
-ZwQueryDirectoryObject
-ZwQueryEaFile
-ZwQueryEvent
-ZwQueryFullAttributesFile
-ZwQueryInformationAtom
-ZwQueryInformationFile
-ZwQueryInformationJobObject
-ZwQueryInformationPort
-ZwQueryInformationProcess
-ZwQueryInformationThread
-ZwQueryInformationToken
-ZwQueryInstallUILanguage
-ZwQueryIntervalProfile
-ZwQueryIoCompletion
-ZwQueryKey
-ZwQueryMultipleValueKey
-ZwQueryMutant
-ZwQueryObject
-ZwQueryOpenSubKeys
-ZwQueryPerformanceCounter
-ZwQueryPortInformationProcess
-ZwQueryQuotaInformationFile
-ZwQuerySection
-ZwQuerySecurityObject
-ZwQuerySemaphore
-ZwQuerySymbolicLinkObject
-ZwQuerySystemEnvironmentValue
-ZwQuerySystemEnvironmentValueEx
-ZwQuerySystemInformation
-ZwQuerySystemTime
-ZwQueryTimer
-ZwQueryTimerResolution
-ZwQueryValueKey
-ZwQueryVirtualMemory
-ZwQueryVolumeInformationFile
-ZwQueueApcThread
-ZwRaiseException
-ZwRaiseHardError
-ZwReadFile
-ZwReadFileScatter
-ZwReadRequestData
-ZwReadVirtualMemory
-ZwRegisterThreadTerminatePort
-ZwReleaseKeyedEvent
-ZwReleaseMutant
-ZwReleaseSemaphore
-ZwRemoveIoCompletion
-ZwRemoveProcessDebug
-ZwRenameKey
-ZwReplaceKey
-ZwReplyPort
-ZwReplyWaitReceivePort
-ZwReplyWaitReceivePortEx
-ZwReplyWaitReplyPort
-ZwRequestPort
-ZwRequestWaitReplyPort
-ZwResetEvent
-ZwResetWriteWatch
-ZwRestoreKey
-ZwResumeProcess
-ZwResumeThread
-ZwSaveKey
-ZwSaveKeyEx
-ZwSaveMergedKeys
-ZwSecureConnectPort
-ZwSetBootEntryOrder
-ZwSetBootOptions
-ZwSetContextThread
-ZwSetDebugFilterState
-ZwSetDefaultHardErrorPort
-ZwSetDefaultLocale
-ZwSetDefaultUILanguage
-ZwSetEaFile
-ZwSetEvent
-ZwSetEventBoostPriority
-ZwSetHighEventPair
-ZwSetHighWaitLowEventPair
-ZwSetInformationDebugObject
-ZwSetInformationFile
-ZwSetInformationJobObject
-ZwSetInformationKey
-ZwSetInformationObject
-ZwSetInformationProcess
-ZwSetInformationThread
-ZwSetInformationToken
-ZwSetIntervalProfile
-ZwSetIoCompletion
-ZwSetLdtEntries
-ZwSetLowEventPair
-ZwSetLowWaitHighEventPair
-ZwSetQuotaInformationFile
-ZwSetSecurityObject
-ZwSetSystemEnvironmentValue
-ZwSetSystemEnvironmentValueEx
-ZwSetSystemInformation
-ZwSetSystemPowerState
-ZwSetSystemTime
-ZwSetThreadExecutionState
-ZwSetTimer
-ZwSetTimerResolution
-ZwSetUuidSeed
-ZwSetValueKey
-ZwSetVolumeInformationFile
-ZwShutdownSystem
-ZwSignalAndWaitForSingleObject
-ZwStartProfile
-ZwStopProfile
-ZwSuspendProcess
-ZwSuspendThread
-ZwSystemDebugControl
-ZwTerminateJobObject
-ZwTerminateProcess
-ZwTerminateThread
-ZwTestAlert
-ZwTraceEvent
-ZwTranslateFilePath
-ZwUnloadDriver
-ZwUnloadKey
-ZwUnloadKeyEx
-ZwUnlockFile
-ZwUnlockVirtualMemory
-ZwUnmapViewOfSection
-ZwVdmControl
-ZwWaitForDebugEvent
-ZwWaitForKeyedEvent
-ZwWaitForMultipleObjects
-ZwWaitForSingleObject
-ZwWaitHighEventPair
-ZwWaitLowEventPair
-ZwWriteFile
-ZwWriteFileGather
-ZwWriteRequestData
-ZwWriteVirtualMemory
-ZwYieldExecution
-__isascii
-__iscsym
-__iscsymf
-__toascii
-_alldiv
-_alldvrm
-_allmul
-_allrem
-_allshl
-_allshr
-_atoi64
-_aulldiv
-_aulldvrm
-_aullrem
-_aullshr
-_fltused
-_i64toa
-_i64tow
-_itoa
-_itow
-_lfind
-_ltoa
-_ltow
-_memccpy
-_memicmp
-_snprintf
-_snwprintf
-_splitpath
-_strcmpi
-_stricmp
-_strlwr
-_strnicmp
-_strupr
-_ui64toa
-_ui64tow
-_ultoa
-_ultow
-_vsnprintf
-_vsnwprintf
-_wcsicmp
-_wcslwr
-_wcsnicmp
-_wcsupr
-_wtoi
-_wtoi64
-_wtol
-abs
-atan
-atoi
-atol
-bsearch
-ceil
-cos
-fabs
-floor
-isalnum
-isalpha
-iscntrl
-isdigit
-isgraph
-islower
-isprint
-ispunct
-isspace
-isupper
-iswalpha
-iswctype
-iswdigit
-iswlower
-iswspace
-iswxdigit
-isxdigit
-labs
-log
-mbstowcs
-memchr
-memcmp
-memcpy
-memmove
-memset
-pow
-qsort
-sin
-sprintf
-sqrt
-sscanf
-strcat
-strchr
-strcmp
-strcpy
-strcspn
-strlen
-strncat
-strncmp
-strncpy
-strpbrk
-strrchr
-strspn
-strstr
-strtol
-strtoul
-swprintf
-tan
-tolower
-toupper
-towlower
-towupper
-vDbgPrintEx
-vDbgPrintExWithPrefix
-vsprintf
-wcscat
-wcschr
-wcscmp
-wcscpy
-wcscspn
-wcslen
-wcsncat
-wcsncmp
-wcsncpy
-wcspbrk
-wcsrchr
-wcsspn
-wcsstr
-wcstol
-wcstombs
-wcstoul
-__C_specific_handler
-_except_handler4_common
diff --git a/plugins/Dbx_mdbx/src/stdafx.h b/plugins/Dbx_mdbx/src/stdafx.h
index a3b257bc8e..1ea974f262 100644
--- a/plugins/Dbx_mdbx/src/stdafx.h
+++ b/plugins/Dbx_mdbx/src/stdafx.h
@@ -51,7 +51,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #include <m_gui.h>

 #include <m_skin.h>

 

-#include "libmdbx/mdbx.h"

+#include "../../libs/libmdbx/src/mdbx.h"

 

 #ifndef thread_local

 #	define thread_local __declspec(thread)