webrtc/system_wrappers/include/clock.h
Karl Wiberg 2b85792b01 Move rw_lock_wrapper.h to rtc_base/synchronization/
This moves it from an API directory (system_wrappers/include/) to a
non-API directory, which is exactly what we want for utilities like
this.

BUG=webrtc:8445
NOPRESUBMIT=true

Change-Id: Ie2879aca5fc1667e4222499d2a8fc2bba9ae2425
Reviewed-on: https://webrtc-review.googlesource.com/21328
Commit-Queue: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22587}
2018-03-23 19:47:08 +00:00

88 lines
2.7 KiB
C++

/*
* Copyright (c) 2013 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.
*/
#ifndef SYSTEM_WRAPPERS_INCLUDE_CLOCK_H_
#define SYSTEM_WRAPPERS_INCLUDE_CLOCK_H_
#include <memory>
#include "rtc_base/synchronization/rw_lock_wrapper.h"
#include "system_wrappers/include/ntp_time.h"
#include "typedefs.h" // NOLINT(build/include)
namespace webrtc {
// January 1970, in NTP seconds.
const uint32_t kNtpJan1970 = 2208988800UL;
// Magic NTP fractional unit.
const double kMagicNtpFractionalUnit = 4.294967296E+9;
// A clock interface that allows reading of absolute and relative timestamps.
class Clock {
public:
virtual ~Clock() {}
// Return a timestamp in milliseconds relative to some arbitrary source; the
// source is fixed for this clock.
virtual int64_t TimeInMilliseconds() const = 0;
// Return a timestamp in microseconds relative to some arbitrary source; the
// source is fixed for this clock.
virtual int64_t TimeInMicroseconds() const = 0;
// Retrieve an NTP absolute timestamp.
virtual NtpTime CurrentNtpTime() const = 0;
// Retrieve an NTP absolute timestamp in milliseconds.
virtual int64_t CurrentNtpInMilliseconds() const = 0;
// Converts an NTP timestamp to a millisecond timestamp.
static int64_t NtpToMs(uint32_t seconds, uint32_t fractions) {
return NtpTime(seconds, fractions).ToMs();
}
// Returns an instance of the real-time system clock implementation.
static Clock* GetRealTimeClock();
};
class SimulatedClock : public Clock {
public:
explicit SimulatedClock(int64_t initial_time_us);
~SimulatedClock() override;
// Return a timestamp in milliseconds relative to some arbitrary source; the
// source is fixed for this clock.
int64_t TimeInMilliseconds() const override;
// Return a timestamp in microseconds relative to some arbitrary source; the
// source is fixed for this clock.
int64_t TimeInMicroseconds() const override;
// Retrieve an NTP absolute timestamp.
NtpTime CurrentNtpTime() const override;
// Converts an NTP timestamp to a millisecond timestamp.
int64_t CurrentNtpInMilliseconds() const override;
// Advance the simulated clock with a given number of milliseconds or
// microseconds.
void AdvanceTimeMilliseconds(int64_t milliseconds);
void AdvanceTimeMicroseconds(int64_t microseconds);
private:
int64_t time_us_;
std::unique_ptr<RWLockWrapper> lock_;
};
}; // namespace webrtc
#endif // SYSTEM_WRAPPERS_INCLUDE_CLOCK_H_