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 // <shared_mutex> 11 12 // template <class Mutex> class shared_lock; 13 14 // void lock(); 15 16 #include <shared_mutex> 17 #include <thread> 18 #include <vector> 19 #include <cstdlib> 20 #include <cassert> 21 22 #if _LIBCPP_STD_VER > 11 23 24 std::shared_timed_mutex m; 25 26 typedef std::chrono::system_clock Clock; 27 typedef Clock::time_point time_point; 28 typedef Clock::duration duration; 29 typedef std::chrono::milliseconds ms; 30 typedef std::chrono::nanoseconds ns; 31 32 void f() 33 { 34 std::shared_lock<std::shared_timed_mutex> lk(m, std::defer_lock); 35 time_point t0 = Clock::now(); 36 lk.lock(); 37 time_point t1 = Clock::now(); 38 assert(lk.owns_lock() == true); 39 ns d = t1 - t0 - ms(250); 40 assert(d < ms(25)); // within 25ms 41 try 42 { 43 lk.lock(); 44 assert(false); 45 } 46 catch (std::system_error& e) 47 { 48 assert(e.code().value() == EDEADLK); 49 } 50 lk.unlock(); 51 lk.release(); 52 try 53 { 54 lk.lock(); 55 assert(false); 56 } 57 catch (std::system_error& e) 58 { 59 assert(e.code().value() == EPERM); 60 } 61 } 62 63 #endif // _LIBCPP_STD_VER > 11 64 65 int main() 66 { 67 #if _LIBCPP_STD_VER > 11 68 m.lock(); 69 std::vector<std::thread> v; 70 for (int i = 0; i < 5; ++i) 71 v.push_back(std::thread(f)); 72 std::this_thread::sleep_for(ms(250)); 73 m.unlock(); 74 for (auto& t : v) 75 t.join(); 76 #endif // _LIBCPP_STD_VER > 11 77 } 78