1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
|
// Copyright Oliver Kowalke 2013.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_FIBERS_CONDITION_VARIABLE_H
#define BOOST_FIBERS_CONDITION_VARIABLE_H
#include <algorithm>
#include <atomic>
#include <chrono>
#include <functional>
#include <mutex>
#include <boost/assert.hpp>
#include <boost/config.hpp>
#include <boost/fiber/context.hpp>
#include <boost/fiber/detail/config.hpp>
#include <boost/fiber/detail/convert.hpp>
#include <boost/fiber/detail/spinlock.hpp>
#include <boost/fiber/exceptions.hpp>
#include <boost/fiber/mutex.hpp>
#include <boost/fiber/operations.hpp>
#ifdef BOOST_HAS_ABI_HEADERS
# include BOOST_ABI_PREFIX
#endif
#ifdef _MSC_VER
# pragma warning(push)
//# pragma warning(disable:4251)
#endif
namespace boost {
namespace fibers {
enum class cv_status {
no_timeout = 1,
timeout
};
class BOOST_FIBERS_DECL condition_variable_any {
private:
typedef context::wait_queue_t wait_queue_t;
detail::spinlock wait_queue_splk_{};
wait_queue_t wait_queue_{};
public:
condition_variable_any() = default;
~condition_variable_any() {
BOOST_ASSERT( wait_queue_.empty() );
}
condition_variable_any( condition_variable_any const&) = delete;
condition_variable_any & operator=( condition_variable_any const&) = delete;
void notify_one() noexcept;
void notify_all() noexcept;
template< typename LockType >
void wait( LockType & lt) {
context * active_ctx = context::active();
// atomically call lt.unlock() and block on *this
// store this fiber in waiting-queue
detail::spinlock_lock lk{ wait_queue_splk_ };
BOOST_ASSERT( ! active_ctx->wait_is_linked() );
active_ctx->wait_link( wait_queue_);
active_ctx->twstatus.store( static_cast< std::intptr_t >( 0), std::memory_order_release);
// unlock external lt
lt.unlock();
// suspend this fiber
active_ctx->suspend( lk);
// relock external again before returning
try {
lt.lock();
} catch (...) {
std::terminate();
}
// post-conditions
BOOST_ASSERT( ! active_ctx->wait_is_linked() );
}
template< typename LockType, typename Pred >
void wait( LockType & lt, Pred pred) {
while ( ! pred() ) {
wait( lt);
}
}
template< typename LockType, typename Clock, typename Duration >
cv_status wait_until( LockType & lt, std::chrono::time_point< Clock, Duration > const& timeout_time_) {
context * active_ctx = context::active();
cv_status status = cv_status::no_timeout;
std::chrono::steady_clock::time_point timeout_time = detail::convert( timeout_time_);
// atomically call lt.unlock() and block on *this
// store this fiber in waiting-queue
detail::spinlock_lock lk{ wait_queue_splk_ };
BOOST_ASSERT( ! active_ctx->wait_is_linked() );
active_ctx->wait_link( wait_queue_);
intrusive_ptr_add_ref( active_ctx);
active_ctx->twstatus.store( reinterpret_cast< std::intptr_t >( this), std::memory_order_release);
// unlock external lt
lt.unlock();
// suspend this fiber
if ( ! active_ctx->wait_until( timeout_time, lk) ) {
status = cv_status::timeout;
// relock local lk
lk.lock();
// remove from waiting-queue
wait_queue_.remove( * active_ctx);
// unlock local lk
lk.unlock();
}
// relock external again before returning
try {
lt.lock();
} catch (...) {
std::terminate();
}
// post-conditions
BOOST_ASSERT( ! active_ctx->wait_is_linked() );
return status;
}
template< typename LockType, typename Clock, typename Duration, typename Pred >
bool wait_until( LockType & lt,
std::chrono::time_point< Clock, Duration > const& timeout_time, Pred pred) {
while ( ! pred() ) {
if ( cv_status::timeout == wait_until( lt, timeout_time) ) {
return pred();
}
}
return true;
}
template< typename LockType, typename Rep, typename Period >
cv_status wait_for( LockType & lt, std::chrono::duration< Rep, Period > const& timeout_duration) {
return wait_until( lt,
std::chrono::steady_clock::now() + timeout_duration);
}
template< typename LockType, typename Rep, typename Period, typename Pred >
bool wait_for( LockType & lt, std::chrono::duration< Rep, Period > const& timeout_duration, Pred pred) {
return wait_until( lt,
std::chrono::steady_clock::now() + timeout_duration,
pred);
}
};
class BOOST_FIBERS_DECL condition_variable {
private:
condition_variable_any cnd_;
public:
condition_variable() = default;
condition_variable( condition_variable const&) = delete;
condition_variable & operator=( condition_variable const&) = delete;
void notify_one() noexcept {
cnd_.notify_one();
}
void notify_all() noexcept {
cnd_.notify_all();
}
void wait( std::unique_lock< mutex > & lt) {
// pre-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
cnd_.wait( lt);
// post-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
}
template< typename Pred >
void wait( std::unique_lock< mutex > & lt, Pred pred) {
// pre-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
cnd_.wait( lt, pred);
// post-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
}
template< typename Clock, typename Duration >
cv_status wait_until( std::unique_lock< mutex > & lt,
std::chrono::time_point< Clock, Duration > const& timeout_time) {
// pre-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
cv_status result = cnd_.wait_until( lt, timeout_time);
// post-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
return result;
}
template< typename Clock, typename Duration, typename Pred >
bool wait_until( std::unique_lock< mutex > & lt,
std::chrono::time_point< Clock, Duration > const& timeout_time, Pred pred) {
// pre-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
bool result = cnd_.wait_until( lt, timeout_time, pred);
// post-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
return result;
}
template< typename Rep, typename Period >
cv_status wait_for( std::unique_lock< mutex > & lt,
std::chrono::duration< Rep, Period > const& timeout_duration) {
// pre-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
cv_status result = cnd_.wait_for( lt, timeout_duration);
// post-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
return result;
}
template< typename Rep, typename Period, typename Pred >
bool wait_for( std::unique_lock< mutex > & lt,
std::chrono::duration< Rep, Period > const& timeout_duration, Pred pred) {
// pre-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
bool result = cnd_.wait_for( lt, timeout_duration, pred);
// post-condition
BOOST_ASSERT( lt.owns_lock() );
BOOST_ASSERT( context::active() == lt.mutex()->owner_);
return result;
}
};
}}
#ifdef _MSC_VER
# pragma warning(pop)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
# include BOOST_ABI_SUFFIX
#endif
#endif // BOOST_FIBERS_CONDITION_VARIABLE_H
|
