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_UNIQUE_LOCK_H
10#define _LIBCPP___MUTEX_UNIQUE_LOCK_H
11
12#include <__chrono/duration.h>
13#include <__chrono/time_point.h>
14#include <__config>
15#include <__memory/addressof.h>
16#include <__mutex/tag_types.h>
17#include <__system_error/throw_system_error.h>
18#include <__utility/swap.h>
19#include <cerrno>
20
21#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22# pragma GCC system_header
23#endif
24
25_LIBCPP_BEGIN_NAMESPACE_STD
26
27template <class _Mutex>
28class unique_lock {
29public:
30 typedef _Mutex mutex_type;
31
32private:
33 mutex_type* __m_;
34 bool __owns_;
35
36public:
37 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock() _NOEXCEPT : __m_(nullptr), __owns_(false) {}
38 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI explicit unique_lock(mutex_type& __m)
39 : __m_(std::addressof(__m)), __owns_(true) {
40 __m_->lock();
41 }
42
43 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, defer_lock_t) _NOEXCEPT
44 : __m_(std::addressof(__m)),
45 __owns_(false) {}
46
47 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, try_to_lock_t)
48 : __m_(std::addressof(__m)), __owns_(__m.try_lock()) {}
49
50 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, adopt_lock_t)
51 : __m_(std::addressof(__m)), __owns_(true) {}
52
53 template <class _Clock, class _Duration>
54 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, const chrono::time_point<_Clock, _Duration>& __t)
55 : __m_(std::addressof(__m)), __owns_(__m.try_lock_until(__t)) {}
56
57 template <class _Rep, class _Period>
58 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock(mutex_type& __m, const chrono::duration<_Rep, _Period>& __d)
59 : __m_(std::addressof(__m)), __owns_(__m.try_lock_for(__d)) {}
60
61 _LIBCPP_HIDE_FROM_ABI ~unique_lock() {
62 if (__owns_)
63 __m_->unlock();
64 }
65
66 unique_lock(unique_lock const&) = delete;
67 unique_lock& operator=(unique_lock const&) = delete;
68
69 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI unique_lock(unique_lock&& __u) _NOEXCEPT
70 : __m_(__u.__m_),
71 __owns_(__u.__owns_) {
72 __u.__m_ = nullptr;
73 __u.__owns_ = false;
74 }
75
76 _LIBCPP_HIDE_FROM_ABI unique_lock& operator=(unique_lock&& __u) _NOEXCEPT {
77 if (__owns_)
78 __m_->unlock();
79
80 __m_ = __u.__m_;
81 __owns_ = __u.__owns_;
82 __u.__m_ = nullptr;
83 __u.__owns_ = false;
84 return *this;
85 }
86
87 _LIBCPP_HIDE_FROM_ABI void lock();
88 _LIBCPP_HIDE_FROM_ABI bool try_lock();
89
90 template <class _Rep, class _Period>
91 _LIBCPP_HIDE_FROM_ABI bool try_lock_for(const chrono::duration<_Rep, _Period>& __d);
92
93 template <class _Clock, class _Duration>
94 _LIBCPP_HIDE_FROM_ABI bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
95
96 _LIBCPP_HIDE_FROM_ABI void unlock();
97
98 _LIBCPP_HIDE_FROM_ABI void swap(unique_lock& __u) _NOEXCEPT {
99 std::swap(__m_, __u.__m_);
100 std::swap(__owns_, __u.__owns_);
101 }
102
103 _LIBCPP_HIDE_FROM_ABI mutex_type* release() _NOEXCEPT {
104 mutex_type* __m = __m_;
105 __m_ = nullptr;
106 __owns_ = false;
107 return __m;
108 }
109
110 _LIBCPP_HIDE_FROM_ABI bool owns_lock() const _NOEXCEPT { return __owns_; }
111 _LIBCPP_HIDE_FROM_ABI explicit operator bool() const _NOEXCEPT { return __owns_; }
112 _LIBCPP_HIDE_FROM_ABI mutex_type* mutex() const _NOEXCEPT { return __m_; }
113};
114_LIBCPP_CTAD_SUPPORTED_FOR_TYPE(unique_lock);
115
116template <class _Mutex>
117_LIBCPP_HIDE_FROM_ABI void unique_lock<_Mutex>::lock() {
118 if (__m_ == nullptr)
119 std::__throw_system_error(EPERM, what_arg: "unique_lock::lock: references null mutex");
120 if (__owns_)
121 std::__throw_system_error(EDEADLK, what_arg: "unique_lock::lock: already locked");
122 __m_->lock();
123 __owns_ = true;
124}
125
126template <class _Mutex>
127_LIBCPP_HIDE_FROM_ABI bool unique_lock<_Mutex>::try_lock() {
128 if (__m_ == nullptr)
129 std::__throw_system_error(EPERM, what_arg: "unique_lock::try_lock: references null mutex");
130 if (__owns_)
131 std::__throw_system_error(EDEADLK, what_arg: "unique_lock::try_lock: already locked");
132 __owns_ = __m_->try_lock();
133 return __owns_;
134}
135
136template <class _Mutex>
137template <class _Rep, class _Period>
138_LIBCPP_HIDE_FROM_ABI bool unique_lock<_Mutex>::try_lock_for(const chrono::duration<_Rep, _Period>& __d) {
139 if (__m_ == nullptr)
140 std::__throw_system_error(EPERM, what_arg: "unique_lock::try_lock_for: references null mutex");
141 if (__owns_)
142 std::__throw_system_error(EDEADLK, what_arg: "unique_lock::try_lock_for: already locked");
143 __owns_ = __m_->try_lock_for(__d);
144 return __owns_;
145}
146
147template <class _Mutex>
148template <class _Clock, class _Duration>
149_LIBCPP_HIDE_FROM_ABI bool unique_lock<_Mutex>::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t) {
150 if (__m_ == nullptr)
151 std::__throw_system_error(EPERM, what_arg: "unique_lock::try_lock_until: references null mutex");
152 if (__owns_)
153 std::__throw_system_error(EDEADLK, what_arg: "unique_lock::try_lock_until: already locked");
154 __owns_ = __m_->try_lock_until(__t);
155 return __owns_;
156}
157
158template <class _Mutex>
159_LIBCPP_HIDE_FROM_ABI void unique_lock<_Mutex>::unlock() {
160 if (!__owns_)
161 std::__throw_system_error(EPERM, what_arg: "unique_lock::unlock: not locked");
162 __m_->unlock();
163 __owns_ = false;
164}
165
166template <class _Mutex>
167inline _LIBCPP_HIDE_FROM_ABI void swap(unique_lock<_Mutex>& __x, unique_lock<_Mutex>& __y) _NOEXCEPT {
168 __x.swap(__y);
169}
170
171_LIBCPP_END_NAMESPACE_STD
172
173#endif // _LIBCPP___MUTEX_UNIQUE_LOCK_H
174