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 // UNSUPPORTED: no-filesystem 11 12 // Filesystem is supported on Apple platforms starting with macosx10.15. 13 // UNSUPPORTED: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}} 14 15 // <chrono> 16 // 17 // file_clock 18 // 19 // template<class Duration> 20 // static sys_time<see-below> to_sys(const file_time<Duration>&); 21 // 22 // template<class Duration> 23 // static file_time<see-below> from_sys(const sys_time<Duration>&); 24 25 #include <chrono> 26 #include <cassert> 27 main(int,char **)28int main(int, char**) { 29 // Test round-trip through the system clock, starting from file_clock::now() 30 { 31 std::chrono::file_clock::time_point const ft = std::chrono::file_clock::now(); 32 auto st = std::chrono::file_clock::to_sys(ft); 33 assert(ft == std::chrono::file_clock::from_sys(st)); 34 } 35 36 // Test round-trip through the system clock, starting from system_clock::now() 37 { 38 std::chrono::system_clock::time_point const st = std::chrono::system_clock::now(); 39 auto ft = std::chrono::file_clock::from_sys(st); 40 assert(st == std::chrono::file_clock::to_sys(ft)); 41 } 42 43 // Make sure the value we get is in the ballpark of something reasonable 44 { 45 std::chrono::file_clock::time_point const file_now = std::chrono::file_clock::now(); 46 std::chrono::system_clock::time_point const sys_now = std::chrono::system_clock::now(); 47 { 48 auto diff = sys_now - std::chrono::file_clock::to_sys(file_now); 49 assert(std::chrono::milliseconds(-500) < diff && diff < std::chrono::milliseconds(500)); 50 } 51 { 52 auto diff = std::chrono::file_clock::from_sys(sys_now) - file_now; 53 assert(std::chrono::milliseconds(-500) < diff && diff < std::chrono::milliseconds(500)); 54 } 55 } 56 57 // Make sure to_sys and from_sys are consistent with each other 58 { 59 std::chrono::file_clock::time_point const ft = std::chrono::file_clock::now(); 60 std::chrono::system_clock::time_point const st = std::chrono::system_clock::now(); 61 auto sys_diff = std::chrono::file_clock::to_sys(ft) - st; 62 auto file_diff = ft - std::chrono::file_clock::from_sys(st); 63 assert(sys_diff == file_diff); 64 } 65 66 return 0; 67 } 68