xref: /freebsd/contrib/llvm-project/libcxx/include/__mutex/lock_guard.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
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_LOCK_GUARD_H
10 #define _LIBCPP___MUTEX_LOCK_GUARD_H
11 
12 #include <__config>
13 #include <__mutex/tag_types.h>
14 
15 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
16 #  pragma GCC system_header
17 #endif
18 
19 _LIBCPP_BEGIN_NAMESPACE_STD
20 
21 template <class _Mutex>
_LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable)22 class _LIBCPP_TEMPLATE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable) lock_guard {
23 public:
24   typedef _Mutex mutex_type;
25 
26 private:
27   mutex_type& __m_;
28 
29 public:
30   _LIBCPP_NODISCARD
31   _LIBCPP_HIDE_FROM_ABI explicit lock_guard(mutex_type& __m) _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability(__m))
32       : __m_(__m) {
33     __m_.lock();
34   }
35 
36   _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI lock_guard(mutex_type& __m, adopt_lock_t)
37       _LIBCPP_THREAD_SAFETY_ANNOTATION(requires_capability(__m))
38       : __m_(__m) {}
39   _LIBCPP_HIDE_FROM_ABI ~lock_guard() _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()) { __m_.unlock(); }
40 
41   lock_guard(lock_guard const&)            = delete;
42   lock_guard& operator=(lock_guard const&) = delete;
43 };
44 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(lock_guard);
45 
46 _LIBCPP_END_NAMESPACE_STD
47 
48 #endif // _LIBCPP___MUTEX_LOCK_GUARD_H
49