1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // UNSUPPORTED: c++03, c++11, c++14, c++17 10 11 // UNSUPPORTED: availability-filesystem-missing 12 13 // <chrono> 14 // 15 // file_clock 16 // 17 // template<class Duration> 18 // static sys_time<see-below> to_sys(const file_time<Duration>&); 19 // 20 // template<class Duration> 21 // static file_time<see-below> from_sys(const sys_time<Duration>&); 22 23 #include <chrono> 24 #include <cassert> 25 main(int,char **)26int main(int, char**) { 27 // Test round-trip through the system clock, starting from file_clock::now() 28 { 29 std::chrono::file_clock::time_point const ft = std::chrono::file_clock::now(); 30 auto st = std::chrono::file_clock::to_sys(ft); 31 assert(ft == std::chrono::file_clock::from_sys(st)); 32 } 33 34 // Test round-trip through the system clock, starting from system_clock::now() 35 { 36 std::chrono::system_clock::time_point const st = std::chrono::system_clock::now(); 37 auto ft = std::chrono::file_clock::from_sys(st); 38 assert(st == std::chrono::file_clock::to_sys(ft)); 39 } 40 41 // Make sure the value we get is in the ballpark of something reasonable 42 { 43 std::chrono::file_clock::time_point const file_now = std::chrono::file_clock::now(); 44 std::chrono::system_clock::time_point const sys_now = std::chrono::system_clock::now(); 45 { 46 auto diff = sys_now - std::chrono::file_clock::to_sys(file_now); 47 assert(std::chrono::milliseconds(-500) < diff && diff < std::chrono::milliseconds(500)); 48 } 49 { 50 auto diff = std::chrono::file_clock::from_sys(sys_now) - file_now; 51 assert(std::chrono::milliseconds(-500) < diff && diff < std::chrono::milliseconds(500)); 52 } 53 } 54 55 // Make sure to_sys and from_sys are consistent with each other 56 { 57 std::chrono::file_clock::time_point const ft = std::chrono::file_clock::now(); 58 std::chrono::system_clock::time_point const st = std::chrono::system_clock::now(); 59 auto sys_diff = std::chrono::file_clock::to_sys(ft) - st; 60 auto file_diff = ft - std::chrono::file_clock::from_sys(st); 61 assert(sys_diff == file_diff); 62 } 63 64 return 0; 65 } 66