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 // UNSUPPORTED: libcpp-has-no-threads 11 12 // FLAKY_TEST 13 14 // <condition_variable> 15 16 // class condition_variable; 17 18 // template <class Rep, class Period> 19 // cv_status 20 // wait_for(unique_lock<mutex>& lock, 21 // const chrono::duration<Rep, Period>& rel_time); 22 23 #include <condition_variable> 24 #include <mutex> 25 #include <thread> 26 #include <chrono> 27 #include <cassert> 28 29 std::condition_variable cv; 30 std::mutex mut; 31 32 int test1 = 0; 33 int test2 = 0; 34 35 int runs = 0; 36 37 void f() 38 { 39 typedef std::chrono::system_clock Clock; 40 typedef std::chrono::milliseconds milliseconds; 41 std::unique_lock<std::mutex> lk(mut); 42 assert(test2 == 0); 43 test1 = 1; 44 cv.notify_one(); 45 Clock::time_point t0 = Clock::now(); 46 while (test2 == 0 && 47 cv.wait_for(lk, milliseconds(250)) == std::cv_status::no_timeout) 48 ; 49 Clock::time_point t1 = Clock::now(); 50 if (runs == 0) 51 { 52 assert(t1 - t0 < milliseconds(250)); 53 assert(test2 != 0); 54 } 55 else 56 { 57 assert(t1 - t0 - milliseconds(250) < milliseconds(50)); 58 assert(test2 == 0); 59 } 60 ++runs; 61 } 62 63 int main() 64 { 65 { 66 std::unique_lock<std::mutex>lk(mut); 67 std::thread t(f); 68 assert(test1 == 0); 69 while (test1 == 0) 70 cv.wait(lk); 71 assert(test1 != 0); 72 test2 = 1; 73 lk.unlock(); 74 cv.notify_one(); 75 t.join(); 76 } 77 test1 = 0; 78 test2 = 0; 79 { 80 std::unique_lock<std::mutex>lk(mut); 81 std::thread t(f); 82 assert(test1 == 0); 83 while (test1 == 0) 84 cv.wait(lk); 85 assert(test1 != 0); 86 lk.unlock(); 87 t.join(); 88 } 89 } 90
