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/*
* libjingle
* Copyright 2008, Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef TALK_BASE_TIMING_H_
#define TALK_BASE_TIMING_H_
#if defined(WIN32)
#include "talk/base/win32.h"
#endif
namespace talk_base {
class Timing {
public:
Timing();
virtual ~Timing();
// WallTimeNow() returns the current wall-clock time in seconds,
// within 10 milliseconds resolution.
virtual double WallTimeNow();
// TimerNow() is like WallTimeNow(), but is monotonically
// increasing. It returns seconds in resolution of 10 microseconds
// or better. Although timer and wall-clock time have the same
// timing unit, they do not necessarily correlate because wall-clock
// time may be adjusted backwards, hence not monotonic.
// Made virtual so we can make a fake one.
virtual double TimerNow();
// BusyWait() exhausts CPU as long as the time elapsed is less than
// the specified interval in seconds. Returns the actual waiting
// time based on TimerNow() measurement.
double BusyWait(double period);
// IdleWait() relinquishes control of CPU for specified period in
// seconds. It uses highest resolution sleep mechanism as possible,
// but does not otherwise guarantee the accuracy. Returns the
// actual waiting time based on TimerNow() measurement.
//
// This function is not re-entrant for an object. Create a fresh
// Timing object for each thread.
double IdleWait(double period);
private:
#if defined(WIN32)
HANDLE timer_handle_;
#endif
};
} // namespace talk_base
#endif // TALK_BASE_TIMING_H_
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