net/quic/core/quic_clock.cc

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/quic/core/quic_clock.h"

#include "base/time/time.h"

namespace net {

QuicClock::QuicClock() {}

QuicClock::~QuicClock() {}

QuicTime QuicClock::ApproximateNow() const {
  // At the moment, Chrome does not have a distinct notion of ApproximateNow().
  // We should consider implementing this using MessageLoop::recent_time_.
  return Now();
}

QuicTime QuicClock::Now() const {
  return QuicTime(base::TimeTicks::Now());
}

QuicWallTime QuicClock::WallNow() const {
  return QuicWallTime::FromUNIXMicroseconds(base::Time::Now().ToJavaTime() *
                                            1000);
}

QuicTime QuicClock::ConvertWallTimeToQuicTime(
    const QuicWallTime& walltime) const {
  //     ..........................
  //     |            |           |
  // unix epoch   |walltime|   WallNow()
  //     ..........................
  //            |     |           |
  //     clock epoch  |         Now()
  //               result
  //
  // result = Now() - (WallNow() - walltime)
  return Now() - QuicTime::Delta::FromMicroseconds(
                     WallNow()
                         .Subtract(QuicTime::Delta::FromMicroseconds(
                             walltime.ToUNIXMicroseconds()))
                         .ToUNIXMicroseconds());
}

}  // namespace net