1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <mutex> 11 12 // template <class Mutex> class unique_lock; 13 14 // void lock(); 15 16 #include <mutex> 17 #include <thread> 18 #include <cstdlib> 19 #include <cassert> 20 21 std::mutex m; 22 23 typedef std::chrono::system_clock Clock; 24 typedef Clock::time_point time_point; 25 typedef Clock::duration duration; 26 typedef std::chrono::milliseconds ms; 27 typedef std::chrono::nanoseconds ns; 28 29 void f() 30 { 31 std::unique_lock<std::mutex> lk(m, std::defer_lock); 32 time_point t0 = Clock::now(); 33 lk.lock(); 34 time_point t1 = Clock::now(); 35 assert(lk.owns_lock() == true); 36 ns d = t1 - t0 - ms(250); 37 assert(d < ns(2500000)); // within 2.5ms 38 try 39 { 40 lk.lock(); 41 assert(false); 42 } 43 catch (std::system_error& e) 44 { 45 assert(e.code().value() == EDEADLK); 46 } 47 lk.unlock(); 48 lk.release(); 49 try 50 { 51 lk.lock(); 52 assert(false); 53 } 54 catch (std::system_error& e) 55 { 56 assert(e.code().value() == EPERM); 57 } 58 } 59 60 int main() 61 { 62 m.lock(); 63 std::thread t(f); 64 std::this_thread::sleep_for(ms(250)); 65 m.unlock(); 66 t.join(); 67 } 68
