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/*
* Copyright 2017-2018 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>.
*/
#include "test.h"
namespace chrono {
#define NSEC_PER_SEC 1000000000u
uint32_t ns2fractional(uint32_t ns) {
assert(ns < NSEC_PER_SEC);
/* LY: здесь и далее используется "длинное деление", которое
* для ясности кода оставлено как есть (без ручной оптимизации). Так как
* GCC, Clang и даже MSVC сами давно умеют конвертировать деление на
* константу в быструю reciprocal-форму. */
return ((uint64_t)ns << 32) / NSEC_PER_SEC;
}
uint32_t fractional2ns(uint32_t fractional) {
return (fractional * (uint64_t)NSEC_PER_SEC) >> 32;
}
#define USEC_PER_SEC 1000000u
uint32_t us2fractional(uint32_t us) {
assert(us < USEC_PER_SEC);
return ((uint64_t)us << 32) / USEC_PER_SEC;
}
uint32_t fractional2us(uint32_t fractional) {
return (fractional * (uint64_t)USEC_PER_SEC) >> 32;
}
#define MSEC_PER_SEC 1000u
uint32_t ms2fractional(uint32_t ms) {
assert(ms < MSEC_PER_SEC);
return ((uint64_t)ms << 32) / MSEC_PER_SEC;
}
uint32_t fractional2ms(uint32_t fractional) {
return (fractional * (uint64_t)MSEC_PER_SEC) >> 32;
}
time from_ns(uint64_t ns) {
time result;
result.fixedpoint = ((ns / NSEC_PER_SEC) << 32) |
ns2fractional((uint32_t)(ns % NSEC_PER_SEC));
return result;
}
time from_us(uint64_t us) {
time result;
result.fixedpoint = ((us / USEC_PER_SEC) << 32) |
us2fractional((uint32_t)(us % USEC_PER_SEC));
return result;
}
time from_ms(uint64_t ms) {
time result;
result.fixedpoint = ((ms / MSEC_PER_SEC) << 32) |
ms2fractional((uint32_t)(ms % MSEC_PER_SEC));
return result;
}
time now_realtime() {
#if defined(_WIN32) || defined(_WIN64) || defined(_WINDOWS)
static void(WINAPI * query_time)(LPFILETIME);
if (!query_time) {
query_time = (void(WINAPI *)(LPFILETIME))GetProcAddress(
GetModuleHandle(TEXT("kernel32.dll")),
"GetSystemTimePreciseAsFileTime");
if (!query_time)
query_time = GetSystemTimeAsFileTime;
}
FILETIME filetime;
query_time(&filetime);
uint64_t ns100 =
(uint64_t)filetime.dwHighDateTime << 32 | filetime.dwLowDateTime;
return from_ns((ns100 - UINT64_C(116444736000000000)) * 100u);
#else
struct timespec ts;
if (unlikely(clock_gettime(CLOCK_REALTIME, &ts)))
failure_perror("clock_gettime(CLOCK_REALTIME", errno);
return from_timespec(ts);
#endif
}
time now_motonic() {
#if defined(_WIN32) || defined(_WIN64) || defined(_WINDOWS)
static uint64_t reciprocal;
static LARGE_INTEGER Frequency;
if (reciprocal == 0) {
if (!QueryPerformanceFrequency(&Frequency))
failure_perror("QueryPerformanceFrequency()", GetLastError());
reciprocal = (((UINT64_C(1) << 48) + Frequency.QuadPart / 2 + 1) /
Frequency.QuadPart);
assert(reciprocal);
}
LARGE_INTEGER Counter;
if (!QueryPerformanceCounter(&Counter))
failure_perror("QueryPerformanceCounter()", GetLastError());
time result;
result.fixedpoint = (Counter.QuadPart / Frequency.QuadPart) << 32;
uint64_t mod = Counter.QuadPart % Frequency.QuadPart;
result.fixedpoint += (mod * reciprocal) >> 16;
return result;
#else
struct timespec ts;
if (unlikely(clock_gettime(CLOCK_MONOTONIC, &ts)))
failure_perror("clock_gettime(CLOCK_MONOTONIC)", errno);
return from_timespec(ts);
#endif
}
} /* namespace chrono */
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