| /* |
| * 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 <stdint.h> |
| #include <memory> |
| |
| #include "rtc_base/synchronization/rw_lock_wrapper.h" |
| #include "system_wrappers/include/ntp_time.h" |
| |
| 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() = 0; |
| |
| // Return a timestamp in microseconds relative to some arbitrary source; the |
| // source is fixed for this clock. |
| virtual int64_t TimeInMicroseconds() = 0; |
| |
| // Retrieve an NTP absolute timestamp. |
| virtual NtpTime CurrentNtpTime() = 0; |
| |
| // Retrieve an NTP absolute timestamp in milliseconds. |
| virtual int64_t CurrentNtpInMilliseconds() = 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() override; |
| |
| // Return a timestamp in microseconds relative to some arbitrary source; the |
| // source is fixed for this clock. |
| int64_t TimeInMicroseconds() override; |
| |
| // Retrieve an NTP absolute timestamp. |
| NtpTime CurrentNtpTime() override; |
| |
| // Converts an NTP timestamp to a millisecond timestamp. |
| int64_t CurrentNtpInMilliseconds() 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_ |