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// mutex_type* release() noexcept; 15 16#include <shared_mutex> 17#include <cassert> 18 19#if _LIBCPP_STD_VER > 11 20 21struct mutex 22{ 23 static int lock_count; 24 static int unlock_count; 25 void lock_shared() {++lock_count;} 26 void unlock_shared() {++unlock_count;} 27}; 28 29int mutex::lock_count = 0; 30int mutex::unlock_count = 0; 31 32mutex m; 33 34#endif // _LIBCPP_STD_VER > 11 35 36int main() 37{ 38#if _LIBCPP_STD_VER > 11 39 std::shared_lock<mutex> lk(m); 40 assert(lk.mutex() == &m); 41 assert(lk.owns_lock() == true); 42 assert(mutex::lock_count == 1); 43 assert(mutex::unlock_count == 0); 44 assert(lk.release() == &m); 45 assert(lk.mutex() == nullptr); 46 assert(lk.owns_lock() == false); 47 assert(mutex::lock_count == 1); 48 assert(mutex::unlock_count == 0); 49 static_assert(noexcept(lk.release()), "release must be noexcept"); 50#endif // _LIBCPP_STD_VER > 11 51} 52