1bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant//===----------------------------------------------------------------------===// 2bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant// 3f5256e16dfc425c1d466f6308d4026d529ce9e0bHoward Hinnant// The LLVM Compiler Infrastructure 4bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant// 5b64f8b07c104c6cc986570ac8ee0ed16a9f23976Howard Hinnant// This file is dual licensed under the MIT and the University of Illinois Open 6b64f8b07c104c6cc986570ac8ee0ed16a9f23976Howard Hinnant// Source Licenses. See LICENSE.TXT for details. 7bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant// 8bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant//===----------------------------------------------------------------------===// 9bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 10bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant// <mutex> 11bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 12bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant// template <class Mutex> class unique_lock; 13bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 14bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant// unique_lock(mutex_type& m, try_to_lock_t); 15bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 16bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant#include <mutex> 17bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant#include <thread> 18bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant#include <cstdlib> 19bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant#include <cassert> 20bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 21bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnantstd::mutex m; 22bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 23bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnanttypedef std::chrono::system_clock Clock; 24bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnanttypedef Clock::time_point time_point; 25bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnanttypedef Clock::duration duration; 26bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnanttypedef std::chrono::milliseconds ms; 27bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnanttypedef std::chrono::nanoseconds ns; 28bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 29bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnantvoid f() 30bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant{ 31bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant time_point t0 = Clock::now(); 32bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant { 33bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant std::unique_lock<std::mutex> lk(m, std::try_to_lock); 34bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant assert(lk.owns_lock() == false); 35bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant } 36bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant { 37bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant std::unique_lock<std::mutex> lk(m, std::try_to_lock); 38bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant assert(lk.owns_lock() == false); 39bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant } 40bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant { 41bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant std::unique_lock<std::mutex> lk(m, std::try_to_lock); 42bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant assert(lk.owns_lock() == false); 43bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant } 44bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant while (true) 45bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant { 46bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant std::unique_lock<std::mutex> lk(m, std::try_to_lock); 47bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant if (lk.owns_lock()) 48bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant break; 49bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant } 50bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant time_point t1 = Clock::now(); 51bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant ns d = t1 - t0 - ms(250); 528eba41324c5519557e76092fe8fe98ebb8aa5f5bDaniel Dunbar assert(d < ms(200)); // within 200ms 53bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant} 54bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant 55bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnantint main() 56bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant{ 57bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant m.lock(); 58bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant std::thread t(f); 59bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant std::this_thread::sleep_for(ms(250)); 60bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant m.unlock(); 61bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant t.join(); 62bc8d3f97eb5c958007f2713238472e0c1c8fe02Howard Hinnant} 63