blob: 76f17235ceb9cdb0351dd368cc43f695da76a264 [file] [log] [blame]
/*
* Copyright (c) 2016 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 "webrtc/test/drifting_clock.h"
#include "webrtc/base/checks.h"
namespace webrtc {
namespace test {
const float DriftingClock::kDoubleSpeed = 2.0f;
const float DriftingClock::kNoDrift = 1.0f;
const float DriftingClock::kHalfSpeed = 0.5f;
DriftingClock::DriftingClock(Clock* clock, float speed)
: clock_(clock),
drift_(speed - 1.0f),
start_time_(clock_->TimeInMicroseconds()) {
RTC_CHECK(clock);
RTC_CHECK_GT(speed, 0.0f);
}
float DriftingClock::Drift() const {
int64_t now = clock_->TimeInMicroseconds();
RTC_DCHECK_GE(now, start_time_);
return (now - start_time_) * drift_;
}
int64_t DriftingClock::TimeInMilliseconds() const {
return clock_->TimeInMilliseconds() + Drift() / 1000.;
}
int64_t DriftingClock::TimeInMicroseconds() const {
return clock_->TimeInMicroseconds() + Drift();
}
void DriftingClock::CurrentNtp(uint32_t& seconds, uint32_t& fractions) const {
// NTP precision is 1/2^32 seconds, i.e. 2^32 ntp fractions = 1 second.
const double kNtpFracPerMicroSecond = 4294.967296; // = 2^32 / 10^6
clock_->CurrentNtp(seconds, fractions);
uint64_t total_fractions = (static_cast<uint64_t>(seconds) << 32) | fractions;
total_fractions += Drift() * kNtpFracPerMicroSecond;
seconds = total_fractions >> 32;
fractions = static_cast<uint32_t>(total_fractions);
}
int64_t DriftingClock::CurrentNtpInMilliseconds() const {
return clock_->CurrentNtpInMilliseconds() + Drift() / 1000.;
}
} // namespace test
} // namespace webrtc