1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___MUTEX_MUTEX_H 10 #define _LIBCPP___MUTEX_MUTEX_H 11 12 #include <__config> 13 #include <__threading_support> 14 #include <__type_traits/is_nothrow_default_constructible.h> 15 16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17 # pragma GCC system_header 18 #endif 19 20 #ifndef _LIBCPP_HAS_NO_THREADS 21 22 _LIBCPP_BEGIN_NAMESPACE_STD 23 24 class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_THREAD_SAFETY_ANNOTATION(capability("mutex")) mutex { 25 __libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER; 26 27 public: 28 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR mutex() = default; 29 30 mutex(const mutex&) = delete; 31 mutex& operator=(const mutex&) = delete; 32 33 # if defined(_LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION) 34 _LIBCPP_HIDE_FROM_ABI ~mutex() = default; 35 # else 36 ~mutex() _NOEXCEPT; 37 # endif 38 39 void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability()); 40 bool try_lock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(try_acquire_capability(true)); 41 void unlock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()); 42 43 typedef __libcpp_mutex_t* native_handle_type; 44 _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() { return &__m_; } 45 }; 46 47 static_assert(is_nothrow_default_constructible<mutex>::value, "the default constructor for std::mutex must be nothrow"); 48 49 _LIBCPP_END_NAMESPACE_STD 50 51 #endif // _LIBCPP_HAS_NO_THREADS 52 53 #endif // _LIBCPP___MUTEX_MUTEX_H 54