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/*
* Copyright (C) 2006 Apple Inc. All rights reserved.
* Copyright (C) 2008 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 COPYRIGHT
* OWNER OR CONTRIBUTORS 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 CurrentTime_h
#define CurrentTime_h
#include <chrono>
#include <time.h>
namespace WTF {
// Returns the current UTC time in seconds, counted from January 1, 1970.
// Precision varies depending on platform but is usually as good or better
// than a millisecond.
// Use this function only if wall clock time is needed. For elapsed time
// measurement use monotonicallyIncreasingTime() instead.
WTF_EXPORT_PRIVATE double currentTime();
// Same thing, in milliseconds.
inline double currentTimeMS()
{
return currentTime() * 1000.0;
}
// Provides a monotonically increasing time in seconds since an arbitrary point in the past.
// On unsupported platforms, this function only guarantees the result will be non-decreasing.
// Result of this function increases monotonically even when clock time goes back due to
// NTP or manual adjustments, so it is better suited for elapsed time measurement.
WTF_EXPORT_PRIVATE double monotonicallyIncreasingTime();
inline double monotonicallyIncreasingTimeMS()
{
return monotonicallyIncreasingTime() * 1000.0;
}
// Returns the current CPU time of the current thread.
// Precision varies depending on platform but is usually as good or better
// than a millisecond.
WTF_EXPORT_PRIVATE std::chrono::microseconds currentCPUTime();
} // namespace WTF
using WTF::currentTime;
using WTF::currentTimeMS;
using WTF::monotonicallyIncreasingTime;
using WTF::monotonicallyIncreasingTimeMS;
using WTF::currentCPUTime;
#endif // CurrentTime_h
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