net/quic/quic_clock.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_QUIC_QUIC_CLOCK_H_
   6 #define NET_QUIC_QUIC_CLOCK_H_
   7
   8 #include "base/basictypes.h"
   9 #include "net/base/net_export.h"
  10 #include "net/quic/quic_time.h"
  11
  12 namespace net {
  13
  14 typedef double WallTime;
  15
  16 // Clock to efficiently retrieve an approximately accurate time from an
  17 // EpollServer.
  18 class NET_EXPORT_PRIVATE QuicClock {
  19  public:
  20   QuicClock();
  21   virtual ~QuicClock();
  22
  23   // Returns the approximate current time as a QuicTime object.
  24   virtual QuicTime ApproximateNow() const;
  25
  26   // Returns the current time as a QuicTime object.
  27   // Note: this use significant resources please use only if needed.
  28   virtual QuicTime Now() const;
  29
  30   // WallNow returns the current wall-time - a time that is consistent across
  31   // different clocks.
  32   virtual QuicWallTime WallNow() const;
  33
  34  private:
  35   DISALLOW_COPY_AND_ASSIGN(QuicClock);
  36 };
  37
  38 }  // namespace net
  39
  40 #endif  // NET_QUIC_QUIC_CLOCK_H_