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/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <stdint.h>
#if defined(WEBRTC_POSIX)
#include <sys/time.h>
#endif
#include "rtc_base/checks.h"
#include "rtc_base/numerics/safe_conversions.h"
#include "rtc_base/system_time.h"
#include "rtc_base/time_utils.h"
#if defined(WEBRTC_WIN)
#include "rtc_base/win32.h"
#endif
#if defined(WEBRTC_WIN)
#include <minwinbase.h>
#endif
namespace rtc {
#if defined(WEBRTC_WIN) || defined(WINUWP)
// FileTime (January 1st 1601) to Unix time (January 1st 1970)
// offset in units of 100ns.
static constexpr uint64_t kFileTimeToUnixTimeEpochOffset =
116444736000000000ULL;
static constexpr uint64_t kFileTimeToMicroSeconds = 10LL;
#endif
ClockInterface* g_clock = nullptr;
ClockInterface* SetClockForTesting(ClockInterface* clock) {
ClockInterface* prev = g_clock;
g_clock = clock;
return prev;
}
ClockInterface* GetClockForTesting() {
return g_clock;
}
#if defined(WINUWP)
namespace {
class TimeHelper final {
public:
TimeHelper(const TimeHelper&) = delete;
// Resets the clock based upon an NTP server. This routine must be called
// prior to the main system start-up to ensure all clocks are based upon
// an NTP server time if NTP synchronization is required. No critical
// section is used thus this method must be called prior to any clock
// routines being used.
static void SyncWithNtp(int64_t ntp_server_time_ms) {
auto& singleton = Singleton();
TIME_ZONE_INFORMATION time_zone;
GetTimeZoneInformation(&time_zone);
int64_t time_zone_bias_ns =
rtc::dchecked_cast<int64_t>(time_zone.Bias) * 60 * 1000 * 1000 * 1000;
singleton.app_start_time_ns_ =
(ntp_server_time_ms - kNTPTimeToUnixTimeEpochOffset) * 1000000 -
time_zone_bias_ns;
singleton.UpdateReferenceTime();
}
// Returns the number of nanoseconds that have passed since unix epoch.
static int64_t TicksNs() {
auto& singleton = Singleton();
int64_t result = 0;
LARGE_INTEGER qpcnt;
QueryPerformanceCounter(&qpcnt);
result = rtc::dchecked_cast<int64_t>(
(rtc::dchecked_cast<uint64_t>(qpcnt.QuadPart) * 100000 /
rtc::dchecked_cast<uint64_t>(singleton.os_ticks_per_second_)) *
10000);
result = singleton.app_start_time_ns_ + result -
singleton.time_since_os_start_ns_;
return result;
}
private:
TimeHelper() {
TIME_ZONE_INFORMATION time_zone;
GetTimeZoneInformation(&time_zone);
int64_t time_zone_bias_ns =
rtc::dchecked_cast<int64_t>(time_zone.Bias) * 60 * 1000 * 1000 * 1000;
FILETIME ft;
// This will give us system file in UTC format.
GetSystemTimeAsFileTime(&ft);
LARGE_INTEGER li;
li.HighPart = ft.dwHighDateTime;
li.LowPart = ft.dwLowDateTime;
app_start_time_ns_ = (li.QuadPart - kFileTimeToUnixTimeEpochOffset) * 100 -
time_zone_bias_ns;
UpdateReferenceTime();
}
static TimeHelper& Singleton() {
static TimeHelper singleton;
return singleton;
}
void UpdateReferenceTime() {
LARGE_INTEGER qpfreq;
QueryPerformanceFrequency(&qpfreq);
os_ticks_per_second_ = rtc::dchecked_cast<int64_t>(qpfreq.QuadPart);
LARGE_INTEGER qpcnt;
QueryPerformanceCounter(&qpcnt);
time_since_os_start_ns_ = rtc::dchecked_cast<int64_t>(
(rtc::dchecked_cast<uint64_t>(qpcnt.QuadPart) * 100000 /
rtc::dchecked_cast<uint64_t>(os_ticks_per_second_)) *
10000);
}
private:
static constexpr uint64_t kNTPTimeToUnixTimeEpochOffset = 2208988800000L;
// The number of nanoseconds since unix system epoch
int64_t app_start_time_ns_;
// The number of nanoseconds since the OS started
int64_t time_since_os_start_ns_;
// The OS calculated ticks per second
int64_t os_ticks_per_second_;
};
} // namespace
void SyncWithNtp(int64_t time_from_ntp_server_ms) {
TimeHelper::SyncWithNtp(time_from_ntp_server_ms);
}
int64_t WinUwpSystemTimeNanos() {
return TimeHelper::TicksNs();
}
#endif // defined(WINUWP)
int64_t SystemTimeMillis() {
return static_cast<int64_t>(SystemTimeNanos() / kNumNanosecsPerMillisec);
}
int64_t TimeNanos() {
if (g_clock) {
return g_clock->TimeNanos();
}
return SystemTimeNanos();
}
uint32_t Time32() {
return static_cast<uint32_t>(TimeNanos() / kNumNanosecsPerMillisec);
}
int64_t TimeMillis() {
return TimeNanos() / kNumNanosecsPerMillisec;
}
int64_t TimeMicros() {
return TimeNanos() / kNumNanosecsPerMicrosec;
}
int64_t TimeAfter(int64_t elapsed) {
RTC_DCHECK_GE(elapsed, 0);
return TimeMillis() + elapsed;
}
int32_t TimeDiff32(uint32_t later, uint32_t earlier) {
return later - earlier;
}
int64_t TimeDiff(int64_t later, int64_t earlier) {
return later - earlier;
}
int64_t TmToSeconds(const tm& tm) {
static short int mdays[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
static short int cumul_mdays[12] = {0, 31, 59, 90, 120, 151,
181, 212, 243, 273, 304, 334};
int year = tm.tm_year + 1900;
int month = tm.tm_mon;
int day = tm.tm_mday - 1; // Make 0-based like the rest.
int hour = tm.tm_hour;
int min = tm.tm_min;
int sec = tm.tm_sec;
bool expiry_in_leap_year =
(year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
if (year < 1970)
return -1;
if (month < 0 || month > 11)
return -1;
if (day < 0 || day >= mdays[month] + (expiry_in_leap_year && month == 2 - 1))
return -1;
if (hour < 0 || hour > 23)
return -1;
if (min < 0 || min > 59)
return -1;
if (sec < 0 || sec > 59)
return -1;
day += cumul_mdays[month];
// Add number of leap days between 1970 and the expiration year, inclusive.
day += ((year / 4 - 1970 / 4) - (year / 100 - 1970 / 100) +
(year / 400 - 1970 / 400));
// We will have added one day too much above if expiration is during a leap
// year, and expiration is in January or February.
if (expiry_in_leap_year && month <= 2 - 1) // `month` is zero based.
day -= 1;
// Combine all variables into seconds from 1970-01-01 00:00 (except `month`
// which was accumulated into `day` above).
return (((static_cast<int64_t>(year - 1970) * 365 + day) * 24 + hour) * 60 +
min) *
60 +
sec;
}
int64_t TimeUTCMicros() {
if (g_clock) {
return g_clock->TimeNanos() / kNumNanosecsPerMicrosec;
}
#if defined(WEBRTC_POSIX)
struct timeval time;
gettimeofday(&time, nullptr);
// Convert from second (1.0) and microsecond (1e-6).
return (static_cast<int64_t>(time.tv_sec) * rtc::kNumMicrosecsPerSec +
time.tv_usec);
#elif defined(WEBRTC_WIN)
FILETIME ft;
// This will give us system file in UTC format in multiples of 100ns.
GetSystemTimeAsFileTime(&ft);
LARGE_INTEGER li;
li.HighPart = ft.dwHighDateTime;
li.LowPart = ft.dwLowDateTime;
return (li.QuadPart - kFileTimeToUnixTimeEpochOffset) /
kFileTimeToMicroSeconds;
#endif
}
int64_t TimeUTCMillis() {
return TimeUTCMicros() / kNumMicrosecsPerMillisec;
}
} // namespace rtc