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Diffstat (limited to 'plugins/FreeImage/src/LibPNG/pngpriv.h')
| -rw-r--r-- | plugins/FreeImage/src/LibPNG/pngpriv.h | 1629 |
1 files changed, 1629 insertions, 0 deletions
diff --git a/plugins/FreeImage/src/LibPNG/pngpriv.h b/plugins/FreeImage/src/LibPNG/pngpriv.h new file mode 100644 index 0000000000..02cc5d8c53 --- /dev/null +++ b/plugins/FreeImage/src/LibPNG/pngpriv.h @@ -0,0 +1,1629 @@ +
+/* pngpriv.h - private declarations for use inside libpng
+ *
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * Last changed in libpng 1.5.7 [December 15, 2011]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+/* The symbols declared in this file (including the functions declared
+ * as PNG_EXTERN) are PRIVATE. They are not part of the libpng public
+ * interface, and are not recommended for use by regular applications.
+ * Some of them may become public in the future; others may stay private,
+ * change in an incompatible way, or even disappear.
+ * Although the libpng users are not forbidden to include this header,
+ * they should be well aware of the issues that may arise from doing so.
+ */
+
+#ifndef PNGPRIV_H
+#define PNGPRIV_H
+
+/* Feature Test Macros. The following are defined here to ensure that correctly
+ * implemented libraries reveal the APIs libpng needs to build and hide those
+ * that are not needed and potentially damaging to the compilation.
+ *
+ * Feature Test Macros must be defined before any system header is included (see
+ * POSIX 1003.1 2.8.2 "POSIX Symbols."
+ *
+ * These macros only have an effect if the operating system supports either
+ * POSIX 1003.1 or C99, or both. On other operating systems (particularly
+ * Windows/Visual Studio) there is no effect; the OS specific tests below are
+ * still required (as of 2011-05-02.)
+ */
+#define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
+
+/* This is required for the definition of abort(), used as a last ditch
+ * error handler when all else fails.
+ */
+#include <stdlib.h>
+
+/* This is used to find 'offsetof', used below for alignment tests. */
+#include <stddef.h>
+
+#define PNGLIB_BUILD /*libpng is being built, not used*/
+
+#ifdef PNG_USER_CONFIG
+# include "pngusr.h"
+ /* These should have been defined in pngusr.h */
+# ifndef PNG_USER_PRIVATEBUILD
+# define PNG_USER_PRIVATEBUILD "Custom libpng build"
+# endif
+# ifndef PNG_USER_DLLFNAME_POSTFIX
+# define PNG_USER_DLLFNAME_POSTFIX "Cb"
+# endif
+#endif
+
+/* Is this a build of a DLL where compilation of the object modules requires
+ * different preprocessor settings to those required for a simple library? If
+ * so PNG_BUILD_DLL must be set.
+ *
+ * If libpng is used inside a DLL but that DLL does not export the libpng APIs
+ * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
+ * static library of libpng then link the DLL against that.
+ */
+#ifndef PNG_BUILD_DLL
+# ifdef DLL_EXPORT
+ /* This is set by libtool when files are compiled for a DLL; libtool
+ * always compiles twice, even on systems where it isn't necessary. Set
+ * PNG_BUILD_DLL in case it is necessary:
+ */
+# define PNG_BUILD_DLL
+# else
+# ifdef _WINDLL
+ /* This is set by the Microsoft Visual Studio IDE in projects that
+ * build a DLL. It can't easily be removed from those projects (it
+ * isn't visible in the Visual Studio UI) so it is a fairly reliable
+ * indication that PNG_IMPEXP needs to be set to the DLL export
+ * attributes.
+ */
+# define PNG_BUILD_DLL
+# else
+# ifdef __DLL__
+ /* This is set by the Borland C system when compiling for a DLL
+ * (as above.)
+ */
+# define PNG_BUILD_DLL
+# else
+ /* Add additional compiler cases here. */
+# endif
+# endif
+# endif
+#endif /* Setting PNG_BUILD_DLL if required */
+
+/* See pngconf.h for more details: the builder of the library may set this on
+ * the command line to the right thing for the specific compilation system or it
+ * may be automagically set above (at present we know of no system where it does
+ * need to be set on the command line.)
+ *
+ * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
+ * setting it to the "import" setting for a DLL build.
+ */
+#ifndef PNG_IMPEXP
+# ifdef PNG_BUILD_DLL
+# define PNG_IMPEXP PNG_DLL_EXPORT
+# else
+ /* Not building a DLL, or the DLL doesn't require specific export
+ * definitions.
+ */
+# define PNG_IMPEXP
+# endif
+#endif
+
+/* No warnings for private or deprecated functions in the build: */
+#ifndef PNG_DEPRECATED
+# define PNG_DEPRECATED
+#endif
+#ifndef PNG_PRIVATE
+# define PNG_PRIVATE
+#endif
+
+#include "png.h"
+#include "pnginfo.h"
+#include "pngstruct.h"
+
+/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
+#ifndef PNG_DLL_EXPORT
+# define PNG_DLL_EXPORT
+#endif
+
+/* This is used for 16 bit gamma tables - only the top level pointers are const,
+ * this could be changed:
+ */
+typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
+
+/* Added at libpng-1.2.9 */
+/* Moved to pngpriv.h at libpng-1.5.0 */
+
+/* config.h is created by and PNG_CONFIGURE_LIBPNG is set by the "configure"
+ * script. We may need it here to get the correct configuration on things
+ * like limits.
+ */
+#ifdef PNG_CONFIGURE_LIBPNG
+# ifdef HAVE_CONFIG_H
+# include "config.h"
+# endif
+#endif
+
+/* Moved to pngpriv.h at libpng-1.5.0 */
+/* NOTE: some of these may have been used in external applications as
+ * these definitions were exposed in pngconf.h prior to 1.5.
+ */
+
+/* If you are running on a machine where you cannot allocate more
+ * than 64K of memory at once, uncomment this. While libpng will not
+ * normally need that much memory in a chunk (unless you load up a very
+ * large file), zlib needs to know how big of a chunk it can use, and
+ * libpng thus makes sure to check any memory allocation to verify it
+ * will fit into memory.
+ *
+ * zlib provides 'MAXSEG_64K' which, if defined, indicates the
+ * same limit and pngconf.h (already included) sets the limit
+ * if certain operating systems are detected.
+ */
+#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
+# define PNG_MAX_MALLOC_64K
+#endif
+
+#ifndef PNG_UNUSED
+/* Unused formal parameter warnings are silenced using the following macro
+ * which is expected to have no bad effects on performance (optimizing
+ * compilers will probably remove it entirely). Note that if you replace
+ * it with something other than whitespace, you must include the terminating
+ * semicolon.
+ */
+# define PNG_UNUSED(param) (void)param;
+#endif
+
+/* Just a little check that someone hasn't tried to define something
+ * contradictory.
+ */
+#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
+# undef PNG_ZBUF_SIZE
+# define PNG_ZBUF_SIZE 65536L
+#endif
+
+/* PNG_STATIC is used to mark internal file scope functions if they need to be
+ * accessed for implementation tests (see the code in tests/?*).
+ */
+#ifndef PNG_STATIC
+# define PNG_STATIC static
+#endif
+
+/* C99 restrict is used where possible, to do this 'restrict' is defined as
+ * empty if we can't be sure it is supported. configure builds have already
+ * done this work.
+ */
+#ifdef PNG_CONFIGURE_LIBPNG
+# define PNG_RESTRICT restrict
+#else
+ /* Modern compilers support restrict, but assume not for anything not
+ * recognized here:
+ */
+# if defined __GNUC__ || defined _MSC_VER || defined __WATCOMC__
+# define PNG_RESTRICT restrict
+# else
+# define PNG_RESTRICT
+# endif
+#endif
+
+/* If warnings or errors are turned off the code is disabled or redirected here.
+ * From 1.5.4 functions have been added to allow very limited formatting of
+ * error and warning messages - this code will also be disabled here.
+ */
+#ifdef PNG_WARNINGS_SUPPORTED
+# define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
+#else
+# define png_warning(s1,s2) ((void)(s1))
+# define png_chunk_warning(s1,s2) ((void)(s1))
+# define png_warning_parameter(p,number,string) ((void)0)
+# define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
+# define png_warning_parameter_signed(p,number,format,value) ((void)0)
+# define png_formatted_warning(pp,p,message) ((void)(pp))
+# define PNG_WARNING_PARAMETERS(p)
+#endif
+#ifndef PNG_ERROR_TEXT_SUPPORTED
+# define png_error(s1,s2) png_err(s1)
+# define png_chunk_error(s1,s2) png_err(s1)
+# define png_fixed_error(s1,s2) png_err(s1)
+#endif
+
+/* C allows up-casts from (void*) to any pointer and (const void*) to any
+ * pointer to a const object. C++ regards this as a type error and requires an
+ * explicit, static, cast and provides the static_cast<> rune to ensure that
+ * const is not cast away.
+ */
+#ifdef __cplusplus
+# define png_voidcast(type, value) static_cast<type>(value)
+#else
+# define png_voidcast(type, value) (value)
+#endif /* __cplusplus */
+
+#ifndef PNG_EXTERN
+/* The functions exported by PNG_EXTERN are internal functions, which
+ * aren't usually used outside the library (as far as I know), so it is
+ * debatable if they should be exported at all. In the future, when it
+ * is possible to have run-time registry of chunk-handling functions,
+ * some of these might be made available again.
+ *
+ * 1.5.7: turned the use of 'extern' back on, since it is localized to pngpriv.h
+ * it should be safe now (it is unclear why it was turned off.)
+ */
+# define PNG_EXTERN extern
+#endif
+
+/* Some fixed point APIs are still required even if not exported because
+ * they get used by the corresponding floating point APIs. This magic
+ * deals with this:
+ */
+#ifdef PNG_FIXED_POINT_SUPPORTED
+# define PNGFAPI PNGAPI
+#else
+# define PNGFAPI /* PRIVATE */
+#endif
+
+/* Other defines specific to compilers can go here. Try to keep
+ * them inside an appropriate ifdef/endif pair for portability.
+ */
+#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
+ defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
+ /* png.c requires the following ANSI-C constants if the conversion of
+ * floating point to ASCII is implemented therein:
+ *
+ * DBL_DIG Maximum number of decimal digits (can be set to any constant)
+ * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
+ * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
+ */
+# include <float.h>
+
+# if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
+ defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
+ /* We need to check that <math.h> hasn't already been included earlier
+ * as it seems it doesn't agree with <fp.h>, yet we should really use
+ * <fp.h> if possible.
+ */
+# if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
+# include <fp.h>
+# endif
+# else
+# include <math.h>
+# endif
+# if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
+ /* Amiga SAS/C: We must include builtin FPU functions when compiling using
+ * MATH=68881
+ */
+# include <m68881.h>
+# endif
+#endif
+
+/* This provides the non-ANSI (far) memory allocation routines. */
+#if defined(__TURBOC__) && defined(__MSDOS__)
+# include <mem.h>
+# include <alloc.h>
+#endif
+
+#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
+ defined(_WIN32) || defined(__WIN32__)
+# include <windows.h> /* defines _WINDOWS_ macro */
+#endif
+
+/* Moved here around 1.5.0beta36 from pngconf.h */
+/* Users may want to use these so they are not private. Any library
+ * functions that are passed far data must be model-independent.
+ */
+
+/* Memory model/platform independent fns */
+#ifndef PNG_ABORT
+# ifdef _WINDOWS_
+# define PNG_ABORT() ExitProcess(0)
+# else
+# define PNG_ABORT() abort()
+# endif
+#endif
+
+#ifdef USE_FAR_KEYWORD
+/* Use this to make far-to-near assignments */
+# define CHECK 1
+# define NOCHECK 0
+# define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
+# define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
+# define png_strlen _fstrlen
+# define png_memcmp _fmemcmp /* SJT: added */
+# define png_memcpy _fmemcpy
+# define png_memset _fmemset
+#else
+# ifdef _WINDOWS_ /* Favor Windows over C runtime fns */
+# define CVT_PTR(ptr) (ptr)
+# define CVT_PTR_NOCHECK(ptr) (ptr)
+# define png_strlen lstrlenA
+# define png_memcmp memcmp
+# define png_memcpy CopyMemory
+# define png_memset memset
+# else
+# define CVT_PTR(ptr) (ptr)
+# define CVT_PTR_NOCHECK(ptr) (ptr)
+# define png_strlen strlen
+# define png_memcmp memcmp /* SJT: added */
+# define png_memcpy memcpy
+# define png_memset memset
+# endif
+#endif
+
+/* These macros may need to be architecture dependent. */
+#define PNG_ALIGN_NONE 0 /* do not use data alignment */
+#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
+#ifdef offsetof
+# define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
+#else
+# define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
+#endif
+#define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
+
+#ifndef PNG_ALIGN_TYPE
+ /* Default to using aligned access optimizations and requiring alignment to a
+ * multiple of the data type size. Override in a compiler specific fashion
+ * if necessary by inserting tests here:
+ */
+# define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
+#endif
+
+#if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
+ /* This is used because in some compiler implementations non-aligned
+ * structure members are supported, so the offsetof approach below fails.
+ * Set PNG_ALIGN_TO_SIZE=0 for compiler combinations where unaligned access
+ * is good for performance. Do not do this unless you have tested the result
+ * and understand it.
+ */
+# define png_alignof(type) (sizeof (type))
+#else
+# if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
+# define png_alignof(type) offsetof(struct{char c; type t;}, t)
+# else
+# if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
+# define png_alignof(type) (1)
+# endif
+ /* Else leave png_alignof undefined to prevent use thereof */
+# endif
+#endif
+
+/* This implicitly assumes alignment is always to a power of 2. */
+#ifdef png_alignof
+# define png_isaligned(ptr, type)\
+ ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
+#else
+# define png_isaligned(ptr, type) 0
+#endif
+
+/* End of memory model/platform independent support */
+/* End of 1.5.0beta36 move from pngconf.h */
+
+/* CONSTANTS and UTILITY MACROS
+ * These are used internally by libpng and not exposed in the API
+ */
+
+/* Various modes of operation. Note that after an init, mode is set to
+ * zero automatically when the structure is created. Three of these
+ * are defined in png.h because they need to be visible to applications
+ * that call png_set_unknown_chunk().
+ */
+/* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
+/* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
+#define PNG_HAVE_IDAT 0x04
+/* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
+#define PNG_HAVE_IEND 0x10
+#define PNG_HAVE_gAMA 0x20
+#define PNG_HAVE_cHRM 0x40
+#define PNG_HAVE_sRGB 0x80
+#define PNG_HAVE_CHUNK_HEADER 0x100
+#define PNG_WROTE_tIME 0x200
+#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
+#define PNG_BACKGROUND_IS_GRAY 0x800
+#define PNG_HAVE_PNG_SIGNATURE 0x1000
+#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
+
+/* Flags for the transformations the PNG library does on the image data */
+#define PNG_BGR 0x0001
+#define PNG_INTERLACE 0x0002
+#define PNG_PACK 0x0004
+#define PNG_SHIFT 0x0008
+#define PNG_SWAP_BYTES 0x0010
+#define PNG_INVERT_MONO 0x0020
+#define PNG_QUANTIZE 0x0040
+#define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
+#define PNG_BACKGROUND_EXPAND 0x0100
+#define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
+#define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
+#define PNG_RGBA 0x0800
+#define PNG_EXPAND 0x1000
+#define PNG_GAMMA 0x2000
+#define PNG_GRAY_TO_RGB 0x4000
+#define PNG_FILLER 0x8000
+#define PNG_PACKSWAP 0x10000
+#define PNG_SWAP_ALPHA 0x20000
+#define PNG_STRIP_ALPHA 0x40000
+#define PNG_INVERT_ALPHA 0x80000
+#define PNG_USER_TRANSFORM 0x100000
+#define PNG_RGB_TO_GRAY_ERR 0x200000
+#define PNG_RGB_TO_GRAY_WARN 0x400000
+#define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
+#define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
+#define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
+#define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
+#define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
+ /* 0x8000000 unused */
+ /* 0x10000000 unused */
+ /* 0x20000000 unused */
+ /* 0x40000000 unused */
+/* Flags for png_create_struct */
+#define PNG_STRUCT_PNG 0x0001
+#define PNG_STRUCT_INFO 0x0002
+
+/* Scaling factor for filter heuristic weighting calculations */
+#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
+#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
+
+/* Flags for the png_ptr->flags rather than declaring a byte for each one */
+#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
+#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
+#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
+#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
+#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
+#define PNG_FLAG_ZLIB_FINISHED 0x0020
+#define PNG_FLAG_ROW_INIT 0x0040
+#define PNG_FLAG_FILLER_AFTER 0x0080
+#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
+#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
+#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
+#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
+#define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
+#define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
+#define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
+#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000
+#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000
+#define PNG_FLAG_LIBRARY_MISMATCH 0x20000
+#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
+#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
+#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000
+ /* 0x200000 unused */
+ /* 0x400000 unused */
+#define PNG_FLAG_BENIGN_ERRORS_WARN 0x800000 /* Added to libpng-1.4.0 */
+#define PNG_FLAG_ZTXT_CUSTOM_STRATEGY 0x1000000 /* 5 lines added */
+#define PNG_FLAG_ZTXT_CUSTOM_LEVEL 0x2000000 /* to libpng-1.5.4 */
+#define PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL 0x4000000
+#define PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS 0x8000000
+#define PNG_FLAG_ZTXT_CUSTOM_METHOD 0x10000000
+ /* 0x20000000 unused */
+ /* 0x40000000 unused */
+
+#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
+ PNG_FLAG_CRC_ANCILLARY_NOWARN)
+
+#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
+ PNG_FLAG_CRC_CRITICAL_IGNORE)
+
+#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
+ PNG_FLAG_CRC_CRITICAL_MASK)
+
+/* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
+ * can handle at once. This type need be no larger than 16 bits (so maximum of
+ * 65535), this define allows us to discover how big it is, but limited by the
+ * maximuum for png_size_t. The value can be overriden in a library build
+ * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
+ * lower value (e.g. 255 works). A lower value may help memory usage (slightly)
+ * and may even improve performance on some systems (and degrade it on others.)
+ */
+#ifndef ZLIB_IO_MAX
+# define ZLIB_IO_MAX ((uInt)-1)
+#endif
+
+/* Save typing and make code easier to understand */
+
+#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
+ abs((int)((c1).green) - (int)((c2).green)) + \
+ abs((int)((c1).blue) - (int)((c2).blue)))
+
+/* Added to libpng-1.2.6 JB */
+#define PNG_ROWBYTES(pixel_bits, width) \
+ ((pixel_bits) >= 8 ? \
+ ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
+ (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3))
+
+/* PNG_OUT_OF_RANGE returns true if value is outside the range
+ * ideal-delta..ideal+delta. Each argument is evaluated twice.
+ * "ideal" and "delta" should be constants, normally simple
+ * integers, "value" a variable. Added to libpng-1.2.6 JB
+ */
+#define PNG_OUT_OF_RANGE(value, ideal, delta) \
+ ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta))
+
+/* Conversions between fixed and floating point, only defined if
+ * required (to make sure the code doesn't accidentally use float
+ * when it is supposedly disabled.)
+ */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+/* The floating point conversion can't overflow, though it can and
+ * does lose accuracy relative to the original fixed point value.
+ * In practice this doesn't matter because png_fixed_point only
+ * stores numbers with very low precision. The png_ptr and s
+ * arguments are unused by default but are there in case error
+ * checking becomes a requirement.
+ */
+#define png_float(png_ptr, fixed, s) (.00001 * (fixed))
+
+/* The fixed point conversion performs range checking and evaluates
+ * its argument multiple times, so must be used with care. The
+ * range checking uses the PNG specification values for a signed
+ * 32 bit fixed point value except that the values are deliberately
+ * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
+ * (2^31-1) * 100000). 's' is a string that describes the value being
+ * converted.
+ *
+ * NOTE: this macro will raise a png_error if the range check fails,
+ * therefore it is normally only appropriate to use this on values
+ * that come from API calls or other sources where an out of range
+ * error indicates a programming error, not a data error!
+ *
+ * NOTE: by default this is off - the macro is not used - because the
+ * function call saves a lot of code.
+ */
+#ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
+#define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
+ ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
+#else
+PNG_EXTERN png_fixed_point png_fixed PNGARG((png_structp png_ptr, double fp,
+ png_const_charp text));
+#endif
+#endif
+
+/* Constants for known chunk types. If you need to add a chunk, define the name
+ * here. For historical reasons these constants have the form png_<name>; i.e.
+ * the prefix is lower case. Please use decimal values as the parameters to
+ * match the ISO PNG specification and to avoid relying on the C locale
+ * interpretation of character values.
+ *
+ * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
+ * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
+ * to be generated if required.
+ *
+ * PNG_32b correctly produces a value shifted by up to 24 bits, even on
+ * architectures where (int) is only 16 bits.
+ */
+#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
+#define PNG_CHUNK(b1,b2,b3,b4) \
+ (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
+
+#define png_IHDR PNG_CHUNK( 73, 72, 68, 82)
+#define png_IDAT PNG_CHUNK( 73, 68, 65, 84)
+#define png_IEND PNG_CHUNK( 73, 69, 78, 68)
+#define png_PLTE PNG_CHUNK( 80, 76, 84, 69)
+#define png_bKGD PNG_CHUNK( 98, 75, 71, 68)
+#define png_cHRM PNG_CHUNK( 99, 72, 82, 77)
+#define png_gAMA PNG_CHUNK(103, 65, 77, 65)
+#define png_hIST PNG_CHUNK(104, 73, 83, 84)
+#define png_iCCP PNG_CHUNK(105, 67, 67, 80)
+#define png_iTXt PNG_CHUNK(105, 84, 88, 116)
+#define png_oFFs PNG_CHUNK(111, 70, 70, 115)
+#define png_pCAL PNG_CHUNK(112, 67, 65, 76)
+#define png_sCAL PNG_CHUNK(115, 67, 65, 76)
+#define png_pHYs PNG_CHUNK(112, 72, 89, 115)
+#define png_sBIT PNG_CHUNK(115, 66, 73, 84)
+#define png_sPLT PNG_CHUNK(115, 80, 76, 84)
+#define png_sRGB PNG_CHUNK(115, 82, 71, 66)
+#define png_sTER PNG_CHUNK(115, 84, 69, 82)
+#define png_tEXt PNG_CHUNK(116, 69, 88, 116)
+#define png_tIME PNG_CHUNK(116, 73, 77, 69)
+#define png_tRNS PNG_CHUNK(116, 82, 78, 83)
+#define png_zTXt PNG_CHUNK(122, 84, 88, 116)
+
+/* The following will work on (signed char*) strings, whereas the get_uint_32
+ * macro will fail on top-bit-set values because of the sign extension.
+ */
+#define PNG_CHUNK_FROM_STRING(s)\
+ PNG_CHUNK(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
+
+/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
+ * signed and the argument is a (char[]) This macro will fail miserably on
+ * systems where (char) is more than 8 bits.
+ */
+#define PNG_STRING_FROM_CHUNK(s,c)\
+ (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
+ ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
+
+/* Do the same but terminate with a null character. */
+#define PNG_CSTRING_FROM_CHUNK(s,c)\
+ (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
+
+/* Test on flag values as defined in the spec (section 5.4): */
+#define PNG_CHUNK_ANCILLIARY(c) (1 & ((c) >> 29))
+#define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLIARY(c))
+#define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
+#define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
+#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
+
+/* Gamma values (new at libpng-1.5.4): */
+#define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
+#define PNG_GAMMA_MAC_INVERSE 65909
+#define PNG_GAMMA_sRGB_INVERSE 45455
+
+
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/* These functions are used internally in the code. They generally
+ * shouldn't be used unless you are writing code to add or replace some
+ * functionality in libpng. More information about most functions can
+ * be found in the files where the functions are located.
+ */
+
+/* Check the user version string for compatibility, returns false if the version
+ * numbers aren't compatible.
+ */
+PNG_EXTERN int png_user_version_check(png_structp png_ptr,
+ png_const_charp user_png_ver);
+
+/* Allocate memory for an internal libpng struct */
+PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct,PNGARG((int type)),
+ PNG_ALLOCATED);
+
+/* Free memory from internal libpng struct */
+PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
+
+PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct_2,
+ PNGARG((int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)),
+ PNG_ALLOCATED);
+PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
+ png_free_ptr free_fn, png_voidp mem_ptr));
+
+/* Free any memory that info_ptr points to and reset struct. */
+PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+
+/* Function to allocate memory for zlib. PNGAPI is disallowed. */
+PNG_EXTERN PNG_FUNCTION(voidpf,png_zalloc,PNGARG((voidpf png_ptr, uInt items,
+ uInt size)),PNG_ALLOCATED);
+
+/* Function to free memory for zlib. PNGAPI is disallowed. */
+PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
+
+/* Next four functions are used internally as callbacks. PNGCBAPI is required
+ * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
+ * PNGCBAPI at 1.5.0
+ */
+
+PNG_EXTERN void PNGCBAPI png_default_read_data PNGARG((png_structp png_ptr,
+ png_bytep data, png_size_t length));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void PNGCBAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t length));
+#endif
+
+PNG_EXTERN void PNGCBAPI png_default_write_data PNGARG((png_structp png_ptr,
+ png_bytep data, png_size_t length));
+
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+# ifdef PNG_STDIO_SUPPORTED
+PNG_EXTERN void PNGCBAPI png_default_flush PNGARG((png_structp png_ptr));
+# endif
+#endif
+
+/* Reset the CRC variable */
+PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
+
+/* Write the "data" buffer to whatever output you are using */
+PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr,
+ png_const_bytep data, png_size_t length));
+
+/* Read and check the PNG file signature */
+PNG_EXTERN void png_read_sig PNGARG((png_structp png_ptr, png_infop info_ptr));
+
+/* Read the chunk header (length + type name) */
+PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr));
+
+/* Read data from whatever input you are using into the "data" buffer */
+PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
+ png_size_t length));
+
+/* Read bytes into buf, and update png_ptr->crc */
+PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
+ png_size_t length));
+
+/* Decompress data in a chunk that uses compression */
+#if defined(PNG_READ_COMPRESSED_TEXT_SUPPORTED)
+PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
+ int comp_type, png_size_t chunklength, png_size_t prefix_length,
+ png_size_t *data_length));
+#endif
+
+/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
+PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
+
+/* Read the CRC from the file and compare it to the libpng calculated CRC */
+PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
+
+/* Calculate the CRC over a section of data. Note that we are only
+ * passing a maximum of 64K on systems that have this as a memory limit,
+ * since this is the maximum buffer size we can specify.
+ */
+PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr,
+ png_const_bytep ptr, png_size_t length));
+
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
+#endif
+
+/* Write various chunks */
+
+/* Write the IHDR chunk, and update the png_struct with the necessary
+ * information.
+ */
+PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
+ png_uint_32 height,
+ int bit_depth, int color_type, int compression_method, int filter_method,
+ int interlace_method));
+
+PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr,
+ png_const_colorp palette, png_uint_32 num_pal));
+
+PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
+ png_size_t length));
+
+PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
+
+#ifdef PNG_WRITE_gAMA_SUPPORTED
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
+# endif
+# ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr,
+ png_fixed_point file_gamma));
+# endif
+#endif
+
+#ifdef PNG_WRITE_sBIT_SUPPORTED
+PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr,
+ png_const_color_8p sbit, int color_type));
+#endif
+
+#ifdef PNG_WRITE_cHRM_SUPPORTED
+# ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
+ double white_x, double white_y,
+ double red_x, double red_y, double green_x, double green_y,
+ double blue_x, double blue_y));
+# endif
+PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
+ png_fixed_point int_white_x, png_fixed_point int_white_y,
+ png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
+ int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
+ png_fixed_point int_blue_y));
+#endif
+
+#ifdef PNG_WRITE_sRGB_SUPPORTED
+PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
+ int intent));
+#endif
+
+#ifdef PNG_WRITE_iCCP_SUPPORTED
+PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
+ png_const_charp name, int compression_type,
+ png_const_charp profile, int proflen));
+ /* Note to maintainer: profile should be png_bytep */
+#endif
+
+#ifdef PNG_WRITE_sPLT_SUPPORTED
+PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
+ png_const_sPLT_tp palette));
+#endif
+
+#ifdef PNG_WRITE_tRNS_SUPPORTED
+PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr,
+ png_const_bytep trans, png_const_color_16p values, int number,
+ int color_type));
+#endif
+
+#ifdef PNG_WRITE_bKGD_SUPPORTED
+PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
+ png_const_color_16p values, int color_type));
+#endif
+
+#ifdef PNG_WRITE_hIST_SUPPORTED
+PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr,
+ png_const_uint_16p hist, int num_hist));
+#endif
+
+/* Chunks that have keywords */
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
+ defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
+ png_const_charp key, png_charpp new_key));
+#endif
+
+#ifdef PNG_WRITE_tEXt_SUPPORTED
+PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_const_charp key,
+ png_const_charp text, png_size_t text_len));
+#endif
+
+#ifdef PNG_WRITE_zTXt_SUPPORTED
+PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_const_charp key,
+ png_const_charp text, png_size_t text_len, int compression));
+#endif
+
+#ifdef PNG_WRITE_iTXt_SUPPORTED
+PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
+ int compression, png_const_charp key, png_const_charp lang,
+ png_const_charp lang_key, png_const_charp text));
+#endif
+
+#ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
+PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_const_textp text_ptr, int num_text));
+#endif
+
+#ifdef PNG_WRITE_oFFs_SUPPORTED
+PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
+ png_int_32 x_offset, png_int_32 y_offset, int unit_type));
+#endif
+
+#ifdef PNG_WRITE_pCAL_SUPPORTED
+PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
+ png_int_32 X0, png_int_32 X1, int type, int nparams,
+ png_const_charp units, png_charpp params));
+#endif
+
+#ifdef PNG_WRITE_pHYs_SUPPORTED
+PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
+ png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
+ int unit_type));
+#endif
+
+#ifdef PNG_WRITE_tIME_SUPPORTED
+PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
+ png_const_timep mod_time));
+#endif
+
+#ifdef PNG_WRITE_sCAL_SUPPORTED
+PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
+ int unit, png_const_charp width, png_const_charp height));
+#endif
+
+/* Called when finished processing a row of data */
+PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
+
+/* Internal use only. Called before first row of data */
+PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
+
+/* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
+ * array of png_ptr->width pixels. If the image is not interlaced or this
+ * is the final pass this just does a png_memcpy, otherwise the "display" flag
+ * is used to determine whether to copy pixels that are not in the current pass.
+ *
+ * Because 'png_do_read_interlace' (below) replicates pixels this allows this
+ * function to achieve the documented 'blocky' appearance during interlaced read
+ * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
+ * are not changed if they are not in the current pass, when display is 0.
+ *
+ * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
+ *
+ * The API always reads from the png_struct row buffer and always assumes that
+ * it is full width (png_do_read_interlace has already been called.)
+ *
+ * This function is only ever used to write to row buffers provided by the
+ * caller of the relevant libpng API and the row must have already been
+ * transformed by the read transformations.
+ *
+ * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
+ * bitmasks for use within the code, otherwise runtime generated masks are used.
+ * The default is compile time masks.
+ */
+#ifndef PNG_USE_COMPILE_TIME_MASKS
+# define PNG_USE_COMPILE_TIME_MASKS 1
+#endif
+PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
+ int display));
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+/* Expand an interlaced row: the 'row_info' describes the pass data that has
+ * been read in and must correspond to the pixels in 'row', the pixels are
+ * expanded (moved apart) in 'row' to match the final layout, when doing this
+ * the pixels are *replicated* to the intervening space. This is essential for
+ * the correct operation of png_combine_row, above.
+ */
+PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
+ png_bytep row, int pass, png_uint_32 transformations));
+#endif
+
+/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+/* Grab pixels out of a row for an interlaced pass */
+PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
+ png_bytep row, int pass));
+#endif
+
+/* Unfilter a row: check the filter value before calling this, there is no point
+ * calling it for PNG_FILTER_VALUE_NONE.
+ */
+PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row, int filter));
+
+PNG_EXTERN void png_read_filter_row_up_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_sub3_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_sub4_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_avg3_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_avg4_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_paeth3_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_paeth4_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+
+/* Choose the best filter to use and filter the row data */
+PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+
+/* Finish a row while reading, dealing with interlacing passes, etc. */
+PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
+
+/* Initialize the row buffers, etc. */
+PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+/* Optional call to update the users info structure */
+PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+#endif
+
+/* These are the functions that do the transformations */
+#ifdef PNG_READ_FILLER_SUPPORTED
+PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
+ png_bytep row, png_uint_32 filler, png_uint_32 flags));
+#endif
+
+#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
+PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
+PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
+PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
+PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
+ defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+PNG_EXTERN void png_do_strip_channel PNGARG((png_row_infop row_info,
+ png_bytep row, int at_start));
+#endif
+
+#ifdef PNG_16BIT_SUPPORTED
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
+ defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr,
+ png_row_infop row_info, png_bytep row));
+#endif
+
+#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
+PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_PACK_SUPPORTED
+PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_SHIFT_SUPPORTED
+PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_color_8p sig_bits));
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+PNG_EXTERN void png_do_scale_16_to_8 PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
+PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+PNG_EXTERN void png_do_quantize PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep palette_lookup,
+ png_const_bytep quantize_lookup));
+
+# ifdef PNG_CORRECT_PALETTE_SUPPORTED
+PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
+ png_colorp palette, int num_palette));
+# endif
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_WRITE_PACK_SUPPORTED
+PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
+ png_bytep row, png_uint_32 bit_depth));
+#endif
+
+#ifdef PNG_WRITE_SHIFT_SUPPORTED
+PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_color_8p bit_depth));
+#endif
+
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
+ defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+PNG_EXTERN void png_do_compose PNGARG((png_row_infop row_info,
+ png_bytep row, png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info,
+ png_bytep row, png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+PNG_EXTERN void png_do_encode_alpha PNGARG((png_row_infop row_info,
+ png_bytep row, png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_EXPAND_SUPPORTED
+PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_colorp palette, png_const_bytep trans,
+ int num_trans));
+PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_color_16p trans_color));
+#endif
+
+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+PNG_EXTERN void png_do_expand_16 PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+/* The following decodes the appropriate chunks, and does error correction,
+ * then calls the appropriate callback for the chunk if it is valid.
+ */
+
+/* Decode the IHDR chunk */
+PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+
+#ifdef PNG_READ_bKGD_SUPPORTED
+PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_cHRM_SUPPORTED
+PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_gAMA_SUPPORTED
+PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_hIST_SUPPORTED
+PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_iCCP_SUPPORTED
+PNG_EXTERN void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif /* PNG_READ_iCCP_SUPPORTED */
+
+#ifdef PNG_READ_iTXt_SUPPORTED
+PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_oFFs_SUPPORTED
+PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_pCAL_SUPPORTED
+PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_pHYs_SUPPORTED
+PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_sBIT_SUPPORTED
+PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_sCAL_SUPPORTED
+PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_sPLT_SUPPORTED
+PNG_EXTERN void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif /* PNG_READ_sPLT_SUPPORTED */
+
+#ifdef PNG_READ_sRGB_SUPPORTED
+PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_tEXt_SUPPORTED
+PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_tIME_SUPPORTED
+PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_tRNS_SUPPORTED
+PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_READ_zTXt_SUPPORTED
+PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
+ png_uint_32 length));
+#endif
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+#endif
+
+PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
+ png_uint_32 chunk_name));
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+/* Exactly as png_handle_as_unknown() except that the argument is a 32-bit chunk
+ * name, not a string.
+ */
+PNG_EXTERN int png_chunk_unknown_handling PNGARG((png_structp png_ptr,
+ png_uint_32 chunk_name));
+#endif
+
+/* Handle the transformations for reading and writing */
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+#endif
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+#endif
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
+ png_uint_32 length));
+PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t buffer_length));
+PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
+ png_bytep buffer, png_size_t buffer_length));
+PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
+PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
+PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
+# ifdef PNG_READ_tEXt_SUPPORTED
+PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+# endif
+# ifdef PNG_READ_zTXt_SUPPORTED
+PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+# endif
+# ifdef PNG_READ_iTXt_SUPPORTED
+PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_uint_32 length));
+PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
+ png_infop info_ptr));
+# endif
+
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
+ png_bytep row));
+PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+/* Added at libpng version 1.4.0 */
+#ifdef PNG_CHECK_cHRM_SUPPORTED
+PNG_EXTERN int png_check_cHRM_fixed PNGARG((png_structp png_ptr,
+ png_fixed_point int_white_x, png_fixed_point int_white_y,
+ png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
+ int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
+ png_fixed_point int_blue_y));
+#endif
+
+#ifdef PNG_CHECK_cHRM_SUPPORTED
+/* Added at libpng version 1.2.34 and 1.4.0 */
+/* Currently only used by png_check_cHRM_fixed */
+PNG_EXTERN void png_64bit_product PNGARG((long v1, long v2,
+ unsigned long *hi_product, unsigned long *lo_product));
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+/* Added at libpng version 1.5.5 */
+typedef struct png_xy
+{
+ png_fixed_point redx, redy;
+ png_fixed_point greenx, greeny;
+ png_fixed_point bluex, bluey;
+ png_fixed_point whitex, whitey;
+} png_xy;
+
+typedef struct png_XYZ
+{
+ png_fixed_point redX, redY, redZ;
+ png_fixed_point greenX, greenY, greenZ;
+ png_fixed_point blueX, blueY, blueZ;
+} png_XYZ;
+
+/* The conversion APIs return 0 on success, non-zero on a parameter error. They
+ * allow conversion between the above representations of a color encoding. When
+ * converting from XYZ end points to chromaticities the absolute magnitude of
+ * the end points is lost, when converting back the sum of the Y values of the
+ * three end points will be 1.0
+ */
+PNG_EXTERN int png_xy_from_XYZ PNGARG((png_xy *xy, png_XYZ XYZ));
+PNG_EXTERN int png_XYZ_from_xy PNGARG((png_XYZ *XYZ, png_xy xy));
+PNG_EXTERN int png_XYZ_from_xy_checked PNGARG((png_structp png_ptr,
+ png_XYZ *XYZ, png_xy xy));
+#endif
+
+/* Added at libpng version 1.4.0 */
+PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
+ png_uint_32 width, png_uint_32 height, int bit_depth,
+ int color_type, int interlace_type, int compression_type,
+ int filter_type));
+
+/* Free all memory used by the read (old method - NOT DLL EXPORTED) */
+PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr,
+ png_infop info_ptr, png_infop end_info_ptr));
+
+/* Free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
+PNG_EXTERN void png_write_destroy PNGARG((png_structp png_ptr));
+
+#ifdef USE_FAR_KEYWORD /* memory model conversion function */
+PNG_EXTERN void *png_far_to_near PNGARG((png_structp png_ptr, png_voidp ptr,
+ int check));
+#endif /* USE_FAR_KEYWORD */
+
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
+PNG_EXTERN PNG_FUNCTION(void, png_fixed_error, (png_structp png_ptr,
+ png_const_charp name),PNG_NORETURN);
+#endif
+
+/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
+ * the end. Always leaves the buffer nul terminated. Never errors out (and
+ * there is no error code.)
+ */
+PNG_EXTERN size_t png_safecat(png_charp buffer, size_t bufsize, size_t pos,
+ png_const_charp string);
+
+/* Various internal functions to handle formatted warning messages, currently
+ * only implemented for warnings.
+ */
+#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
+/* Utility to dump an unsigned value into a buffer, given a start pointer and
+ * and end pointer (which should point just *beyond* the end of the buffer!)
+ * Returns the pointer to the start of the formatted string. This utility only
+ * does unsigned values.
+ */
+PNG_EXTERN png_charp png_format_number(png_const_charp start, png_charp end,
+ int format, png_alloc_size_t number);
+
+/* Convenience macro that takes an array: */
+#define PNG_FORMAT_NUMBER(buffer,format,number) \
+ png_format_number(buffer, buffer + (sizeof buffer), format, number)
+
+/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
+#define PNG_NUMBER_BUFFER_SIZE 24
+
+/* These are the integer formats currently supported, the name is formed from
+ * the standard printf(3) format string.
+ */
+#define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
+#define PNG_NUMBER_FORMAT_02u 2
+#define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
+#define PNG_NUMBER_FORMAT_02d 2
+#define PNG_NUMBER_FORMAT_x 3
+#define PNG_NUMBER_FORMAT_02x 4
+#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
+#endif
+
+#ifdef PNG_WARNINGS_SUPPORTED
+/* New defines and members adding in libpng-1.5.4 */
+# define PNG_WARNING_PARAMETER_SIZE 32
+# define PNG_WARNING_PARAMETER_COUNT 8
+
+/* An l-value of this type has to be passed to the APIs below to cache the
+ * values of the parameters to a formatted warning message.
+ */
+typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
+ PNG_WARNING_PARAMETER_SIZE];
+
+PNG_EXTERN void png_warning_parameter(png_warning_parameters p, int number,
+ png_const_charp string);
+ /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
+ * including the trailing '\0'.
+ */
+PNG_EXTERN void png_warning_parameter_unsigned(png_warning_parameters p,
+ int number, int format, png_alloc_size_t value);
+ /* Use png_alloc_size_t because it is an unsigned type as big as any we
+ * need to output. Use the following for a signed value.
+ */
+PNG_EXTERN void png_warning_parameter_signed(png_warning_parameters p,
+ int number, int format, png_int_32 value);
+
+PNG_EXTERN void png_formatted_warning(png_structp png_ptr,
+ png_warning_parameters p, png_const_charp message);
+ /* 'message' follows the X/Open approach of using @1, @2 to insert
+ * parameters previously supplied using the above functions. Errors in
+ * specifying the paramters will simple result in garbage substitutions.
+ */
+#endif
+
+/* ASCII to FP interfaces, currently only implemented if sCAL
+ * support is required.
+ */
+#if defined(PNG_READ_sCAL_SUPPORTED)
+/* MAX_DIGITS is actually the maximum number of characters in an sCAL
+ * width or height, derived from the precision (number of significant
+ * digits - a build time settable option) and assumpitions about the
+ * maximum ridiculous exponent.
+ */
+#define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+PNG_EXTERN void png_ascii_from_fp PNGARG((png_structp png_ptr, png_charp ascii,
+ png_size_t size, double fp, unsigned int precision));
+#endif /* FLOATING_POINT */
+
+#ifdef PNG_FIXED_POINT_SUPPORTED
+PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr,
+ png_charp ascii, png_size_t size, png_fixed_point fp));
+#endif /* FIXED_POINT */
+#endif /* READ_sCAL */
+
+#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
+/* An internal API to validate the format of a floating point number.
+ * The result is the index of the next character. If the number is
+ * not valid it will be the index of a character in the supposed number.
+ *
+ * The format of a number is defined in the PNG extensions specification
+ * and this API is strictly conformant to that spec, not anyone elses!
+ *
+ * The format as a regular expression is:
+ *
+ * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
+ *
+ * or:
+ *
+ * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
+ *
+ * The complexity is that either integer or fraction must be present and the
+ * fraction is permitted to have no digits only if the integer is present.
+ *
+ * NOTE: The dangling E problem.
+ * There is a PNG valid floating point number in the following:
+ *
+ * PNG floating point numb1.ers are not greedy.
+ *
+ * Working this out requires *TWO* character lookahead (because of the
+ * sign), the parser does not do this - it will fail at the 'r' - this
+ * doesn't matter for PNG sCAL chunk values, but it requires more care
+ * if the value were ever to be embedded in something more complex. Use
+ * ANSI-C strtod if you need the lookahead.
+ */
+/* State table for the parser. */
+#define PNG_FP_INTEGER 0 /* before or in integer */
+#define PNG_FP_FRACTION 1 /* before or in fraction */
+#define PNG_FP_EXPONENT 2 /* before or in exponent */
+#define PNG_FP_STATE 3 /* mask for the above */
+#define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
+#define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
+#define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
+#define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
+#define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
+
+/* These three values don't affect the parser. They are set but not used.
+ */
+#define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
+#define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
+#define PNG_FP_NONZERO 256 /* A non-zero value */
+#define PNG_FP_STICKY 448 /* The above three flags */
+
+/* This is available for the caller to store in 'state' if required. Do not
+ * call the parser after setting it (the parser sometimes clears it.)
+ */
+#define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
+
+/* Result codes for the parser (boolean - true meants ok, false means
+ * not ok yet.)
+ */
+#define PNG_FP_MAYBE 0 /* The number may be valid in the future */
+#define PNG_FP_OK 1 /* The number is valid */
+
+/* Tests on the sticky non-zero and negative flags. To pass these checks
+ * the state must also indicate that the whole number is valid - this is
+ * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
+ * is equivalent to PNG_FP_OK above.)
+ */
+#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
+ /* NZ_MASK: the string is valid and a non-zero negative value */
+#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
+ /* Z MASK: the string is valid and a non-zero value. */
+ /* PNG_FP_SAW_DIGIT: the string is valid. */
+#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
+#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
+#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
+
+/* The actual parser. This can be called repeatedly, it updates
+ * the index into the string and the state variable (which must
+ * be initialzed to 0). It returns a result code, as above. There
+ * is no point calling the parser any more if it fails to advance to
+ * the end of the string - it is stuck on an invalid character (or
+ * terminated by '\0').
+ *
+ * Note that the pointer will consume an E or even an E+ then leave
+ * a 'maybe' state even though a preceding integer.fraction is valid.
+ * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
+ * a valid number. It's possible to recover from this by calling
+ * the parser again (from the start, with state 0) but with a string
+ * that omits the last character (i.e. set the size to the index of
+ * the problem character.) This has not been tested within libpng.
+ */
+PNG_EXTERN int png_check_fp_number PNGARG((png_const_charp string,
+ png_size_t size, int *statep, png_size_tp whereami));
+
+/* This is the same but it checks a complete string and returns true
+ * only if it just contains a floating point number. As of 1.5.4 this
+ * function also returns the state at the end of parsing the number if
+ * it was valid (otherwise it returns 0.) This can be used for testing
+ * for negative or zero values using the sticky flag.
+ */
+PNG_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
+ png_size_t size));
+#endif /* pCAL || sCAL */
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
+ defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
+/* Added at libpng version 1.5.0 */
+/* This is a utility to provide a*times/div (rounded) and indicate
+ * if there is an overflow. The result is a boolean - false (0)
+ * for overflow, true (1) if no overflow, in which case *res
+ * holds the result.
+ */
+PNG_EXTERN int png_muldiv PNGARG((png_fixed_point_p res, png_fixed_point a,
+ png_int_32 multiplied_by, png_int_32 divided_by));
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
+/* Same deal, but issue a warning on overflow and return 0. */
+PNG_EXTERN png_fixed_point png_muldiv_warn PNGARG((png_structp png_ptr,
+ png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by));
+#endif
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+/* Calculate a reciprocal - used for gamma values. This returns
+ * 0 if the argument is 0 in order to maintain an undefined value,
+ * there are no warnings.
+ */
+PNG_EXTERN png_fixed_point png_reciprocal PNGARG((png_fixed_point a));
+
+/* The same but gives a reciprocal of the product of two fixed point
+ * values. Accuracy is suitable for gamma calculations but this is
+ * not exact - use png_muldiv for that.
+ */
+PNG_EXTERN png_fixed_point png_reciprocal2 PNGARG((png_fixed_point a,
+ png_fixed_point b));
+#endif
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+/* Internal fixed point gamma correction. These APIs are called as
+ * required to convert single values - they don't need to be fast,
+ * they are not used when processing image pixel values.
+ *
+ * While the input is an 'unsigned' value it must actually be the
+ * correct bit value - 0..255 or 0..65535 as required.
+ */
+PNG_EXTERN png_uint_16 png_gamma_correct PNGARG((png_structp png_ptr,
+ unsigned int value, png_fixed_point gamma_value));
+PNG_EXTERN int png_gamma_significant PNGARG((png_fixed_point gamma_value));
+PNG_EXTERN png_uint_16 png_gamma_16bit_correct PNGARG((unsigned int value,
+ png_fixed_point gamma_value));
+PNG_EXTERN png_byte png_gamma_8bit_correct PNGARG((unsigned int value,
+ png_fixed_point gamma_value));
+PNG_EXTERN void png_destroy_gamma_table(png_structp png_ptr);
+PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,
+ int bit_depth));
+#endif
+
+/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
+
+#include "pngdebug.h"
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PNGPRIV_H */
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