/* * 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 #include 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(); WTF_EXPORT_PRIVATE void sleep(double); inline void sleepMS(double value) { sleep(value / 1000.0); } } // namespace WTF using WTF::currentCPUTime; using WTF::currentTime; using WTF::currentTimeMS; using WTF::monotonicallyIncreasingTime; using WTF::monotonicallyIncreasingTimeMS; using WTF::sleep; using WTF::sleepMS; #endif // CurrentTime_h