summaryrefslogtreecommitdiffstats
path: root/third_party/libwebrtc/rtc_base/time_utils.cc
diff options
context:
space:
mode:
Diffstat (limited to 'third_party/libwebrtc/rtc_base/time_utils.cc')
-rw-r--r--third_party/libwebrtc/rtc_base/time_utils.cc270
1 files changed, 270 insertions, 0 deletions
diff --git a/third_party/libwebrtc/rtc_base/time_utils.cc b/third_party/libwebrtc/rtc_base/time_utils.cc
new file mode 100644
index 0000000000..96282f06cf
--- /dev/null
+++ b/third_party/libwebrtc/rtc_base/time_utils.cc
@@ -0,0 +1,270 @@
+/*
+ * 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
+
+#if defined(WEBRTC_WIN)
+#include <sys/timeb.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"
+
+namespace rtc {
+
+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 kFileTimeToUnixTimeEpochOffset =
+ 116444736000000000ULL;
+ 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;
+}
+
+TimestampWrapAroundHandler::TimestampWrapAroundHandler()
+ : last_ts_(0), num_wrap_(-1) {}
+
+int64_t TimestampWrapAroundHandler::Unwrap(uint32_t ts) {
+ if (num_wrap_ == -1) {
+ last_ts_ = ts;
+ num_wrap_ = 0;
+ return ts;
+ }
+
+ if (ts < last_ts_) {
+ if (last_ts_ >= 0xf0000000 && ts < 0x0fffffff)
+ ++num_wrap_;
+ } else if ((ts - last_ts_) > 0xf0000000) {
+ // Backwards wrap. Unwrap with last wrap count and don't update last_ts_.
+ return ts + (num_wrap_ - 1) * (int64_t{1} << 32);
+ }
+
+ last_ts_ = ts;
+ return ts + (num_wrap_ << 32);
+}
+
+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)
+ struct _timeb time;
+ _ftime(&time);
+ // Convert from second (1.0) and milliseconds (1e-3).
+ return (static_cast<int64_t>(time.time) * rtc::kNumMicrosecsPerSec +
+ static_cast<int64_t>(time.millitm) * rtc::kNumMicrosecsPerMillisec);
+#endif
+}
+
+int64_t TimeUTCMillis() {
+ return TimeUTCMicros() / kNumMicrosecsPerMillisec;
+}
+
+} // namespace rtc