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 <__thread/support.h>
14#include <__type_traits/is_nothrow_constructible.h>
15
16#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
17# pragma GCC system_header
18#endif
19
20#if _LIBCPP_HAS_THREADS
21
22_LIBCPP_BEGIN_NAMESPACE_STD
23
24class _LIBCPP_EXPORTED_FROM_ABI _LIBCPP_THREAD_SAFETY_ANNOTATION(capability("mutex")) mutex {
25 __libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;
26
27public:
28 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR mutex() = default;
29
30 mutex(const mutex&) = delete;
31 mutex& operator=(const mutex&) = delete;
32
33# if _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
47static_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_THREADS
52
53#endif // _LIBCPP___MUTEX_MUTEX_H
54