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 // <condition_variable> 13 14 // class condition_variable; 15 16 // template <class Predicate> 17 // void wait(unique_lock<mutex>& lock, Predicate pred); 18 19 #include <condition_variable> 20 #include <mutex> 21 #include <thread> 22 #include <functional> 23 #include <cassert> 24 25 std::condition_variable cv; 26 std::mutex mut; 27 28 int test1 = 0; 29 int test2 = 0; 30 31 class Pred 32 { 33 int& i_; 34 public: Pred(int & i)35 explicit Pred(int& i) : i_(i) {} 36 operator ()()37 bool operator()() {return i_ != 0;} 38 }; 39 f()40void f() 41 { 42 std::unique_lock<std::mutex> lk(mut); 43 assert(test2 == 0); 44 test1 = 1; 45 cv.notify_one(); 46 cv.wait(lk, Pred(test2)); 47 assert(test2 != 0); 48 } 49 main()50int main() 51 { 52 std::unique_lock<std::mutex>lk(mut); 53 std::thread t(f); 54 assert(test1 == 0); 55 while (test1 == 0) 56 cv.wait(lk); 57 assert(test1 != 0); 58 test2 = 1; 59 lk.unlock(); 60 cv.notify_one(); 61 t.join(); 62 } 63