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_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  _LIBCPP_ACQUIRE_CAPABILITY() void lock();
40  _LIBCPP_TRY_ACQUIRE_CAPABILITY(true) bool try_lock() _NOEXCEPT;
41  _LIBCPP_RELEASE_CAPABILITY void unlock() _NOEXCEPT;
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