File indexing completed on 2024-05-19 13:30:29
0001 /* 0002 Copyright (C) 2014 Andreas Hartmetz <ahartmetz@gmail.com> 0003 0004 This library is free software; you can redistribute it and/or 0005 modify it under the terms of the GNU Library General Public 0006 License as published by the Free Software Foundation; either 0007 version 2 of the License, or (at your option) any later version. 0008 0009 This library is distributed in the hope that it will be useful, 0010 but WITHOUT ANY WARRANTY; without even the implied warranty of 0011 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 0012 Library General Public License for more details. 0013 0014 You should have received a copy of the GNU Library General Public License 0015 along with this library; see the file COPYING.LGPL. If not, write to 0016 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 0017 Boston, MA 02110-1301, USA. 0018 0019 Alternatively, this file is available under the Mozilla Public License 0020 Version 1.1. You may obtain a copy of the License at 0021 http://www.mozilla.org/MPL/ 0022 */ 0023 0024 #include "platformtime.h" 0025 0026 #ifdef _WIN32 0027 // GetTickCount64() requires Vista or greater which is NT version 0x0600 0028 #define _WIN32_WINNT 0x0600 0029 #define WIN32_LEAN_AND_MEAN 0030 #include "windows.h" 0031 #elif defined(__linux__) 0032 #include <time.h> 0033 #else 0034 #include <chrono> 0035 #endif 0036 0037 namespace PlatformTime 0038 { 0039 0040 uint64 monotonicMsecs() 0041 { 0042 #ifdef _WIN32 0043 return GetTickCount64(); 0044 #elif defined(__linux__) 0045 timespec tspec; 0046 // performance note: at least on Linux AMD64, clock_gettime(CLOCK_MONOTONIC) does not (usually?) 0047 // make a syscall, so it's surprisingly cheap; presumably it uses some built-in CPU timer feature 0048 clock_gettime(CLOCK_MONOTONIC, &tspec); 0049 return uint64(tspec.tv_sec) * 1000 + uint64(tspec.tv_nsec) / 1000000; 0050 #else 0051 auto ret = uint64(std::chrono::duration_cast<std::chrono::milliseconds>( 0052 std::chrono::steady_clock::now().time_since_epoch()).count()); 0053 return ret; 0054 #endif 0055 } 0056 0057 }