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#include <__assert>
10#include <__thread/id.h>
11#include <__utility/exception_guard.h>
12#include <limits>
13#include <mutex>
14
15#include "include/atomic_support.h"
16
17#if defined(__ELF__) && defined(_LIBCPP_LINK_PTHREAD_LIB)
18# pragma comment(lib, "pthread")
19#endif
20
21_LIBCPP_PUSH_MACROS
22#include <__undef_macros>
23
24_LIBCPP_BEGIN_NAMESPACE_STD
25
26// ~mutex is defined elsewhere
27
28void mutex::lock() {
29 int ec = __libcpp_mutex_lock(&__m_);
30 if (ec)
31 __throw_system_error(ec, "mutex lock failed");
32}
33
34bool mutex::try_lock() noexcept { return __libcpp_mutex_trylock(&__m_); }
35
36void mutex::unlock() noexcept {
37 int ec = __libcpp_mutex_unlock(&__m_);
38 (void)ec;
39 _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(
40 ec == 0, "call to mutex::unlock failed. A possible reason is that the mutex wasn't locked");
41}
42
43// recursive_mutex
44
45recursive_mutex::recursive_mutex() {
46 int ec = __libcpp_recursive_mutex_init(&__m_);
47 if (ec)
48 __throw_system_error(ec, "recursive_mutex constructor failed");
49}
50
51recursive_mutex::~recursive_mutex() {
52 int e = __libcpp_recursive_mutex_destroy(&__m_);
53 (void)e;
54 _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(e == 0, "call to ~recursive_mutex() failed");
55}
56
57void recursive_mutex::lock() {
58 int ec = __libcpp_recursive_mutex_lock(&__m_);
59 if (ec)
60 __throw_system_error(ec, "recursive_mutex lock failed");
61}
62
63void recursive_mutex::unlock() noexcept {
64 int e = __libcpp_recursive_mutex_unlock(&__m_);
65 (void)e;
66 _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(
67 e == 0, "call to recursive_mutex::unlock() failed. A possible reason is that the mutex wasn't locked");
68}
69
70bool recursive_mutex::try_lock() noexcept { return __libcpp_recursive_mutex_trylock(&__m_); }
71
72// timed_mutex
73
74timed_mutex::timed_mutex() : __locked_(false) {}
75
76timed_mutex::~timed_mutex() { lock_guard<mutex> _(__m_); }
77
78void timed_mutex::lock() {
79 unique_lock<mutex> lk(__m_);
80 while (__locked_)
81 __cv_.wait(lk);
82 __locked_ = true;
83}
84
85bool timed_mutex::try_lock() noexcept {
86 unique_lock<mutex> lk(__m_, try_to_lock);
87 if (lk.owns_lock() && !__locked_) {
88 __locked_ = true;
89 return true;
90 }
91 return false;
92}
93
94void timed_mutex::unlock() noexcept {
95 lock_guard<mutex> _(__m_);
96 __locked_ = false;
97 __cv_.notify_one();
98}
99
100// recursive_timed_mutex
101
102recursive_timed_mutex::recursive_timed_mutex() : __count_(0), __id_{} {}
103
104recursive_timed_mutex::~recursive_timed_mutex() { lock_guard<mutex> _(__m_); }
105
106void recursive_timed_mutex::lock() {
107 __thread_id id = this_thread::get_id();
108 unique_lock<mutex> lk(__m_);
109 if (id == __id_) {
110 if (__count_ == numeric_limits<size_t>::max())
111 __throw_system_error(EAGAIN, "recursive_timed_mutex lock limit reached");
112 ++__count_;
113 return;
114 }
115 while (__count_ != 0)
116 __cv_.wait(lk);
117 __count_ = 1;
118 __id_ = id;
119}
120
121bool recursive_timed_mutex::try_lock() noexcept {
122 __thread_id id = this_thread::get_id();
123 unique_lock<mutex> lk(__m_, try_to_lock);
124 if (lk.owns_lock() && (__count_ == 0 || id == __id_)) {
125 if (__count_ == numeric_limits<size_t>::max())
126 return false;
127 ++__count_;
128 __id_ = id;
129 return true;
130 }
131 return false;
132}
133
134void recursive_timed_mutex::unlock() noexcept {
135 unique_lock<mutex> lk(__m_);
136 if (--__count_ == 0) {
137 __id_.__reset();
138 lk.unlock();
139 __cv_.notify_one();
140 }
141}
142
143_LIBCPP_END_NAMESPACE_STD
144
145_LIBCPP_POP_MACROS
146

source code of libcxx/src/mutex.cpp