1 | // Copyright (C) 2002-2003 |
---|
2 | // David Moore, Michael Glassford |
---|
3 | // |
---|
4 | // Original scoped_lock implementation |
---|
5 | // Copyright (C) 2001 |
---|
6 | // William E. Kempf |
---|
7 | // |
---|
8 | // Distributed under the Boost Software License, Version 1.0. (See accompanying |
---|
9 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
---|
10 | |
---|
11 | #ifndef BOOST_READ_WRITE_LOCK_JDM031002_HPP |
---|
12 | #define BOOST_READ_WRITE_LOCK_JDM031002_HPP |
---|
13 | |
---|
14 | #include <boost/thread/detail/config.hpp> |
---|
15 | |
---|
16 | #include <boost/utility.hpp> |
---|
17 | #include <boost/thread/exceptions.hpp> |
---|
18 | #include <boost/thread/detail/lock.hpp> |
---|
19 | |
---|
20 | namespace boost { |
---|
21 | |
---|
22 | struct xtime; |
---|
23 | |
---|
24 | namespace read_write_lock_state { |
---|
25 | enum read_write_lock_state_enum |
---|
26 | { |
---|
27 | unlocked=0, |
---|
28 | read_locked=1, |
---|
29 | write_locked=2 |
---|
30 | }; |
---|
31 | } //namespace read_write_lock_state |
---|
32 | |
---|
33 | namespace detail { |
---|
34 | namespace thread { |
---|
35 | |
---|
36 | template <typename Mutex> |
---|
37 | class read_write_lock_ops : private noncopyable |
---|
38 | { |
---|
39 | private: |
---|
40 | |
---|
41 | read_write_lock_ops() { } |
---|
42 | ~read_write_lock_ops() { } |
---|
43 | |
---|
44 | public: |
---|
45 | |
---|
46 | typedef Mutex mutex_type; |
---|
47 | |
---|
48 | static void write_lock(Mutex& m) |
---|
49 | { |
---|
50 | m.do_write_lock(); |
---|
51 | } |
---|
52 | static void read_lock(Mutex& m) |
---|
53 | { |
---|
54 | m.do_read_lock(); |
---|
55 | } |
---|
56 | static void write_unlock(Mutex& m) |
---|
57 | { |
---|
58 | m.do_write_unlock(); |
---|
59 | } |
---|
60 | static void read_unlock(Mutex &m) |
---|
61 | { |
---|
62 | m.do_read_unlock(); |
---|
63 | } |
---|
64 | static bool try_write_lock(Mutex &m) |
---|
65 | { |
---|
66 | return m.do_try_write_lock(); |
---|
67 | } |
---|
68 | static bool try_read_lock(Mutex &m) |
---|
69 | { |
---|
70 | return m.do_try_read_lock(); |
---|
71 | } |
---|
72 | |
---|
73 | static bool timed_write_lock(Mutex &m,const xtime &xt) |
---|
74 | { |
---|
75 | return m.do_timed_write_lock(xt); |
---|
76 | } |
---|
77 | static bool timed_read_lock(Mutex &m,const xtime &xt) |
---|
78 | { |
---|
79 | return m.do_timed_read_lock(xt); |
---|
80 | } |
---|
81 | |
---|
82 | static void demote(Mutex & m) |
---|
83 | { |
---|
84 | m.do_demote_to_read_lock(); |
---|
85 | } |
---|
86 | static bool try_demote(Mutex & m) |
---|
87 | { |
---|
88 | return m.do_try_demote_to_read_lock(); |
---|
89 | } |
---|
90 | static bool timed_demote(Mutex & m,const xtime &xt) |
---|
91 | { |
---|
92 | return m.do_timed_demote_to_read_lock(xt); |
---|
93 | } |
---|
94 | |
---|
95 | static void promote(Mutex & m) |
---|
96 | { |
---|
97 | m.do_promote_to_write_lock(); |
---|
98 | } |
---|
99 | static bool try_promote(Mutex & m) |
---|
100 | { |
---|
101 | return m.do_try_promote_to_write_lock(); |
---|
102 | } |
---|
103 | static bool timed_promote(Mutex & m,const xtime &xt) |
---|
104 | { |
---|
105 | return m.do_timed_promote_to_write_lock(xt); |
---|
106 | } |
---|
107 | }; |
---|
108 | |
---|
109 | template <typename ReadWriteMutex> |
---|
110 | class scoped_read_write_lock : private noncopyable |
---|
111 | { |
---|
112 | public: |
---|
113 | |
---|
114 | typedef ReadWriteMutex mutex_type; |
---|
115 | |
---|
116 | scoped_read_write_lock( |
---|
117 | ReadWriteMutex& mx, |
---|
118 | read_write_lock_state::read_write_lock_state_enum initial_state) |
---|
119 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
120 | { |
---|
121 | if (initial_state == read_write_lock_state::read_locked) |
---|
122 | read_lock(); |
---|
123 | else if (initial_state == read_write_lock_state::write_locked) |
---|
124 | write_lock(); |
---|
125 | } |
---|
126 | |
---|
127 | ~scoped_read_write_lock() |
---|
128 | { |
---|
129 | if (m_state != read_write_lock_state::unlocked) |
---|
130 | unlock(); |
---|
131 | } |
---|
132 | |
---|
133 | void read_lock() |
---|
134 | { |
---|
135 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
136 | read_write_lock_ops<ReadWriteMutex>::read_lock(m_mutex); |
---|
137 | m_state = read_write_lock_state::read_locked; |
---|
138 | } |
---|
139 | |
---|
140 | void write_lock() |
---|
141 | { |
---|
142 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
143 | read_write_lock_ops<ReadWriteMutex>::write_lock(m_mutex); |
---|
144 | m_state = read_write_lock_state::write_locked; |
---|
145 | } |
---|
146 | |
---|
147 | void unlock() |
---|
148 | { |
---|
149 | if (m_state == read_write_lock_state::unlocked) throw lock_error(); |
---|
150 | if (m_state == read_write_lock_state::read_locked) |
---|
151 | read_write_lock_ops<ReadWriteMutex>::read_unlock(m_mutex); |
---|
152 | else //(m_state == read_write_lock_state::write_locked) |
---|
153 | read_write_lock_ops<ReadWriteMutex>::write_unlock(m_mutex); |
---|
154 | |
---|
155 | m_state = read_write_lock_state::unlocked; |
---|
156 | } |
---|
157 | |
---|
158 | void demote(void) |
---|
159 | { |
---|
160 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
161 | read_write_lock_ops<ReadWriteMutex>::demote(m_mutex); |
---|
162 | m_state = read_write_lock_state::read_locked; |
---|
163 | } |
---|
164 | |
---|
165 | void promote(void) |
---|
166 | { |
---|
167 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
168 | read_write_lock_ops<ReadWriteMutex>::promote(m_mutex); |
---|
169 | m_state = read_write_lock_state::write_locked; |
---|
170 | } |
---|
171 | |
---|
172 | //If allow_unlock = true, set_lock always succeeds and |
---|
173 | //the function result indicates whether an unlock was required. |
---|
174 | //If allow_unlock = false, set_lock may fail; |
---|
175 | //the function result indicates whether it succeeded. |
---|
176 | bool set_lock(read_write_lock_state::read_write_lock_state_enum ls, bool allow_unlock = true) |
---|
177 | { |
---|
178 | bool result = !allow_unlock; |
---|
179 | |
---|
180 | if (m_state != ls) |
---|
181 | { |
---|
182 | if (m_state == read_write_lock_state::unlocked) |
---|
183 | { |
---|
184 | if (ls == read_write_lock_state::read_locked) |
---|
185 | read_lock(); |
---|
186 | else //(ls == read_write_lock_state::write_locked) |
---|
187 | write_lock(); |
---|
188 | } |
---|
189 | else //(m_state == read_write_lock_state::read_locked || m_state == read_write_lock_state::write_locked) |
---|
190 | { |
---|
191 | if (ls == read_write_lock_state::read_locked) |
---|
192 | demote(); |
---|
193 | else if (ls == read_write_lock_state::write_locked) |
---|
194 | { |
---|
195 | if (allow_unlock) |
---|
196 | { |
---|
197 | result = true; |
---|
198 | unlock(); |
---|
199 | write_lock(); |
---|
200 | } |
---|
201 | else |
---|
202 | result = false; |
---|
203 | } |
---|
204 | else //(ls == read_write_lock_state::unlocked) |
---|
205 | unlock(); |
---|
206 | } |
---|
207 | } |
---|
208 | |
---|
209 | return result; |
---|
210 | } |
---|
211 | |
---|
212 | bool locked() const |
---|
213 | { |
---|
214 | return m_state != read_write_lock_state::unlocked; |
---|
215 | } |
---|
216 | |
---|
217 | bool read_locked() const |
---|
218 | { |
---|
219 | return m_state == read_write_lock_state::read_locked; |
---|
220 | } |
---|
221 | |
---|
222 | bool write_locked() const |
---|
223 | { |
---|
224 | return m_state != read_write_lock_state::write_locked; |
---|
225 | } |
---|
226 | |
---|
227 | operator const void*() const |
---|
228 | { |
---|
229 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
230 | } |
---|
231 | |
---|
232 | read_write_lock_state::read_write_lock_state_enum state() const |
---|
233 | { |
---|
234 | return m_state; |
---|
235 | } |
---|
236 | |
---|
237 | private: |
---|
238 | |
---|
239 | ReadWriteMutex& m_mutex; |
---|
240 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
241 | }; |
---|
242 | |
---|
243 | template <typename ReadWriteMutex> |
---|
244 | class scoped_read_lock : private noncopyable |
---|
245 | { |
---|
246 | public: |
---|
247 | |
---|
248 | typedef ReadWriteMutex mutex_type; |
---|
249 | |
---|
250 | explicit scoped_read_lock( |
---|
251 | ReadWriteMutex& mx, |
---|
252 | bool initially_locked = true) |
---|
253 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
254 | { |
---|
255 | if (initially_locked) |
---|
256 | lock(); |
---|
257 | } |
---|
258 | |
---|
259 | ~scoped_read_lock() |
---|
260 | { |
---|
261 | if (m_state != read_write_lock_state::unlocked) |
---|
262 | unlock(); |
---|
263 | } |
---|
264 | |
---|
265 | void lock() |
---|
266 | { |
---|
267 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
268 | read_write_lock_ops<ReadWriteMutex>::read_lock(m_mutex); |
---|
269 | m_state = read_write_lock_state::read_locked; |
---|
270 | } |
---|
271 | |
---|
272 | void unlock() |
---|
273 | { |
---|
274 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
275 | read_write_lock_ops<ReadWriteMutex>::read_unlock(m_mutex); |
---|
276 | |
---|
277 | m_state = read_write_lock_state::unlocked; |
---|
278 | } |
---|
279 | |
---|
280 | bool locked() const |
---|
281 | { |
---|
282 | return m_state != read_write_lock_state::unlocked; |
---|
283 | } |
---|
284 | |
---|
285 | operator const void*() const |
---|
286 | { |
---|
287 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
288 | } |
---|
289 | |
---|
290 | private: |
---|
291 | |
---|
292 | ReadWriteMutex& m_mutex; |
---|
293 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
294 | }; |
---|
295 | |
---|
296 | template <typename ReadWriteMutex> |
---|
297 | class scoped_write_lock : private noncopyable |
---|
298 | { |
---|
299 | public: |
---|
300 | |
---|
301 | typedef ReadWriteMutex mutex_type; |
---|
302 | |
---|
303 | explicit scoped_write_lock( |
---|
304 | ReadWriteMutex& mx, |
---|
305 | bool initially_locked = true) |
---|
306 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
307 | { |
---|
308 | if (initially_locked) |
---|
309 | lock(); |
---|
310 | } |
---|
311 | |
---|
312 | ~scoped_write_lock() |
---|
313 | { |
---|
314 | if (m_state != read_write_lock_state::unlocked) |
---|
315 | unlock(); |
---|
316 | } |
---|
317 | |
---|
318 | void lock() |
---|
319 | { |
---|
320 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
321 | read_write_lock_ops<ReadWriteMutex>::write_lock(m_mutex); |
---|
322 | m_state = read_write_lock_state::write_locked; |
---|
323 | } |
---|
324 | |
---|
325 | void unlock() |
---|
326 | { |
---|
327 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
328 | read_write_lock_ops<ReadWriteMutex>::write_unlock(m_mutex); |
---|
329 | |
---|
330 | m_state = read_write_lock_state::unlocked; |
---|
331 | } |
---|
332 | |
---|
333 | bool locked() const |
---|
334 | { |
---|
335 | return m_state != read_write_lock_state::unlocked; |
---|
336 | } |
---|
337 | |
---|
338 | operator const void*() const |
---|
339 | { |
---|
340 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
341 | } |
---|
342 | |
---|
343 | private: |
---|
344 | |
---|
345 | ReadWriteMutex& m_mutex; |
---|
346 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
347 | }; |
---|
348 | |
---|
349 | template <typename TryReadWriteMutex> |
---|
350 | class scoped_try_read_write_lock : private noncopyable |
---|
351 | { |
---|
352 | public: |
---|
353 | |
---|
354 | typedef TryReadWriteMutex mutex_type; |
---|
355 | |
---|
356 | scoped_try_read_write_lock( |
---|
357 | TryReadWriteMutex& mx, |
---|
358 | read_write_lock_state::read_write_lock_state_enum initial_state) |
---|
359 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
360 | { |
---|
361 | if (initial_state == read_write_lock_state::read_locked) |
---|
362 | read_lock(); |
---|
363 | else if (initial_state == read_write_lock_state::write_locked) |
---|
364 | write_lock(); |
---|
365 | } |
---|
366 | |
---|
367 | ~scoped_try_read_write_lock() |
---|
368 | { |
---|
369 | if (m_state != read_write_lock_state::unlocked) |
---|
370 | unlock(); |
---|
371 | } |
---|
372 | |
---|
373 | void read_lock() |
---|
374 | { |
---|
375 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
376 | read_write_lock_ops<TryReadWriteMutex>::read_lock(m_mutex); |
---|
377 | m_state = read_write_lock_state::read_locked; |
---|
378 | } |
---|
379 | |
---|
380 | bool try_read_lock() |
---|
381 | { |
---|
382 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
383 | if(read_write_lock_ops<TryReadWriteMutex>::try_read_lock(m_mutex)) |
---|
384 | { |
---|
385 | m_state = read_write_lock_state::read_locked; |
---|
386 | return true; |
---|
387 | } |
---|
388 | return false; |
---|
389 | } |
---|
390 | |
---|
391 | void write_lock() |
---|
392 | { |
---|
393 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
394 | read_write_lock_ops<TryReadWriteMutex>::write_lock(m_mutex); |
---|
395 | m_state = read_write_lock_state::write_locked; |
---|
396 | } |
---|
397 | |
---|
398 | bool try_write_lock() |
---|
399 | { |
---|
400 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
401 | if(read_write_lock_ops<TryReadWriteMutex>::try_write_lock(m_mutex)) |
---|
402 | { |
---|
403 | m_state = read_write_lock_state::write_locked; |
---|
404 | return true; |
---|
405 | } |
---|
406 | return false; |
---|
407 | } |
---|
408 | |
---|
409 | void unlock() |
---|
410 | { |
---|
411 | if (m_state == read_write_lock_state::unlocked) throw lock_error(); |
---|
412 | if (m_state == read_write_lock_state::read_locked) |
---|
413 | read_write_lock_ops<TryReadWriteMutex>::read_unlock(m_mutex); |
---|
414 | else //(m_state == read_write_lock_state::write_locked) |
---|
415 | read_write_lock_ops<TryReadWriteMutex>::write_unlock(m_mutex); |
---|
416 | |
---|
417 | m_state = read_write_lock_state::unlocked; |
---|
418 | } |
---|
419 | |
---|
420 | void demote(void) |
---|
421 | { |
---|
422 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
423 | read_write_lock_ops<TryReadWriteMutex>::demote(m_mutex); |
---|
424 | m_state = read_write_lock_state::read_locked; |
---|
425 | } |
---|
426 | |
---|
427 | bool try_demote(void) |
---|
428 | { |
---|
429 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
430 | return read_write_lock_ops<TryReadWriteMutex>::try_demote(m_mutex) ? (m_state = read_write_lock_state::read_locked, true) : false; |
---|
431 | } |
---|
432 | |
---|
433 | void promote(void) |
---|
434 | { |
---|
435 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
436 | read_write_lock_ops<TryReadWriteMutex>::promote(m_mutex); |
---|
437 | m_state = read_write_lock_state::write_locked; |
---|
438 | } |
---|
439 | |
---|
440 | bool try_promote(void) |
---|
441 | { |
---|
442 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
443 | return read_write_lock_ops<TryReadWriteMutex>::try_promote(m_mutex) ? (m_state = read_write_lock_state::write_locked, true) : false; |
---|
444 | } |
---|
445 | |
---|
446 | //If allow_unlock = true, set_lock always succeeds and |
---|
447 | //the function result indicates whether an unlock was required. |
---|
448 | //If allow_unlock = false, set_lock may fail; |
---|
449 | //the function result indicates whether it succeeded. |
---|
450 | bool set_lock(read_write_lock_state::read_write_lock_state_enum ls, bool allow_unlock = true) |
---|
451 | { |
---|
452 | bool result = !allow_unlock; |
---|
453 | |
---|
454 | if (m_state != ls) |
---|
455 | { |
---|
456 | if (m_state == read_write_lock_state::unlocked) |
---|
457 | { |
---|
458 | if (ls == read_write_lock_state::read_locked) |
---|
459 | read_lock(); |
---|
460 | else //(ls == read_write_lock_state::write_locked) |
---|
461 | write_lock(); |
---|
462 | } |
---|
463 | else //(m_state == read_write_lock_state::read_locked || m_state == read_write_lock_state::write_locked) |
---|
464 | { |
---|
465 | if (ls == read_write_lock_state::read_locked) |
---|
466 | demote(); |
---|
467 | else if (ls == read_write_lock_state::write_locked) |
---|
468 | { |
---|
469 | if (!try_promote()) |
---|
470 | { |
---|
471 | if (allow_unlock) |
---|
472 | { |
---|
473 | result = true; |
---|
474 | unlock(); |
---|
475 | write_lock(); |
---|
476 | } |
---|
477 | else |
---|
478 | result = false; |
---|
479 | } |
---|
480 | } |
---|
481 | else //(ls == read_write_lock_state::unlocked) |
---|
482 | unlock(); |
---|
483 | } |
---|
484 | } |
---|
485 | |
---|
486 | return result; |
---|
487 | } |
---|
488 | |
---|
489 | bool try_set_lock(read_write_lock_state::read_write_lock_state_enum ls) |
---|
490 | { |
---|
491 | if (m_state != ls) |
---|
492 | { |
---|
493 | if (m_state == read_write_lock_state::unlocked) |
---|
494 | { |
---|
495 | if (ls == read_write_lock_state::read_locked) |
---|
496 | return try_read_lock(); |
---|
497 | else // (ls == read_write_lock_state::write_locked) |
---|
498 | return try_write_lock(); |
---|
499 | } |
---|
500 | else //(m_state == read_write_lock_state::read_locked || m_state == read_write_lock_state::write_locked) |
---|
501 | { |
---|
502 | if (ls == read_write_lock_state::read_locked) |
---|
503 | return try_demote(); |
---|
504 | else if (ls == read_write_lock_state::write_locked) |
---|
505 | return try_promote(); |
---|
506 | else //(ls == read_write_lock_state::unlocked) |
---|
507 | return unlock(), true; |
---|
508 | } |
---|
509 | } |
---|
510 | else //(m_state == ls) |
---|
511 | return true; |
---|
512 | } |
---|
513 | |
---|
514 | bool locked() const |
---|
515 | { |
---|
516 | return m_state != read_write_lock_state::unlocked; |
---|
517 | } |
---|
518 | |
---|
519 | bool read_locked() const |
---|
520 | { |
---|
521 | return m_state == read_write_lock_state::read_locked; |
---|
522 | } |
---|
523 | |
---|
524 | bool write_locked() const |
---|
525 | { |
---|
526 | return m_state != read_write_lock_state::write_locked; |
---|
527 | } |
---|
528 | |
---|
529 | operator const void*() const |
---|
530 | { |
---|
531 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
532 | } |
---|
533 | |
---|
534 | read_write_lock_state::read_write_lock_state_enum state() const |
---|
535 | { |
---|
536 | return m_state; |
---|
537 | } |
---|
538 | |
---|
539 | private: |
---|
540 | |
---|
541 | TryReadWriteMutex& m_mutex; |
---|
542 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
543 | }; |
---|
544 | |
---|
545 | template <typename TryReadWriteMutex> |
---|
546 | class scoped_try_read_lock : private noncopyable |
---|
547 | { |
---|
548 | public: |
---|
549 | |
---|
550 | typedef TryReadWriteMutex mutex_type; |
---|
551 | |
---|
552 | explicit scoped_try_read_lock( |
---|
553 | TryReadWriteMutex& mx, |
---|
554 | bool initially_locked = true) |
---|
555 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
556 | { |
---|
557 | if (initially_locked) |
---|
558 | lock(); |
---|
559 | } |
---|
560 | |
---|
561 | ~scoped_try_read_lock() |
---|
562 | { |
---|
563 | if (m_state != read_write_lock_state::unlocked) |
---|
564 | unlock(); |
---|
565 | } |
---|
566 | |
---|
567 | void lock() |
---|
568 | { |
---|
569 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
570 | read_write_lock_ops<TryReadWriteMutex>::read_lock(m_mutex); |
---|
571 | m_state = read_write_lock_state::read_locked; |
---|
572 | } |
---|
573 | |
---|
574 | bool try_lock() |
---|
575 | { |
---|
576 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
577 | if(read_write_lock_ops<TryReadWriteMutex>::try_read_lock(m_mutex)) |
---|
578 | { |
---|
579 | m_state = read_write_lock_state::read_locked; |
---|
580 | return true; |
---|
581 | } |
---|
582 | return false; |
---|
583 | } |
---|
584 | |
---|
585 | void unlock() |
---|
586 | { |
---|
587 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
588 | read_write_lock_ops<TryReadWriteMutex>::read_unlock(m_mutex); |
---|
589 | |
---|
590 | m_state = read_write_lock_state::unlocked; |
---|
591 | } |
---|
592 | |
---|
593 | bool locked() const |
---|
594 | { |
---|
595 | return m_state != read_write_lock_state::unlocked; |
---|
596 | } |
---|
597 | |
---|
598 | operator const void*() const |
---|
599 | { |
---|
600 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
601 | } |
---|
602 | |
---|
603 | private: |
---|
604 | |
---|
605 | TryReadWriteMutex& m_mutex; |
---|
606 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
607 | }; |
---|
608 | |
---|
609 | template <typename TryReadWriteMutex> |
---|
610 | class scoped_try_write_lock : private noncopyable |
---|
611 | { |
---|
612 | public: |
---|
613 | |
---|
614 | typedef TryReadWriteMutex mutex_type; |
---|
615 | |
---|
616 | explicit scoped_try_write_lock( |
---|
617 | TryReadWriteMutex& mx, |
---|
618 | bool initially_locked = true) |
---|
619 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
620 | { |
---|
621 | if (initially_locked) |
---|
622 | lock(); |
---|
623 | } |
---|
624 | |
---|
625 | ~scoped_try_write_lock() |
---|
626 | { |
---|
627 | if (m_state != read_write_lock_state::unlocked) |
---|
628 | unlock(); |
---|
629 | } |
---|
630 | |
---|
631 | void lock() |
---|
632 | { |
---|
633 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
634 | read_write_lock_ops<TryReadWriteMutex>::write_lock(m_mutex); |
---|
635 | m_state = read_write_lock_state::write_locked; |
---|
636 | } |
---|
637 | |
---|
638 | bool try_lock() |
---|
639 | { |
---|
640 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
641 | if(read_write_lock_ops<TryReadWriteMutex>::try_write_lock(m_mutex)) |
---|
642 | { |
---|
643 | m_state = read_write_lock_state::write_locked; |
---|
644 | return true; |
---|
645 | } |
---|
646 | return false; |
---|
647 | } |
---|
648 | |
---|
649 | void unlock() |
---|
650 | { |
---|
651 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
652 | read_write_lock_ops<TryReadWriteMutex>::write_unlock(m_mutex); |
---|
653 | |
---|
654 | m_state = read_write_lock_state::unlocked; |
---|
655 | } |
---|
656 | |
---|
657 | bool locked() const |
---|
658 | { |
---|
659 | return m_state != read_write_lock_state::unlocked; |
---|
660 | } |
---|
661 | |
---|
662 | operator const void*() const |
---|
663 | { |
---|
664 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
665 | } |
---|
666 | |
---|
667 | private: |
---|
668 | |
---|
669 | TryReadWriteMutex& m_mutex; |
---|
670 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
671 | }; |
---|
672 | |
---|
673 | template <typename TimedReadWriteMutex> |
---|
674 | class scoped_timed_read_write_lock : private noncopyable |
---|
675 | { |
---|
676 | public: |
---|
677 | |
---|
678 | typedef TimedReadWriteMutex mutex_type; |
---|
679 | |
---|
680 | scoped_timed_read_write_lock( |
---|
681 | TimedReadWriteMutex& mx, |
---|
682 | read_write_lock_state::read_write_lock_state_enum initial_state) |
---|
683 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
684 | { |
---|
685 | if (initial_state == read_write_lock_state::read_locked) |
---|
686 | read_lock(); |
---|
687 | else if (initial_state == read_write_lock_state::write_locked) |
---|
688 | write_lock(); |
---|
689 | } |
---|
690 | |
---|
691 | ~scoped_timed_read_write_lock() |
---|
692 | { |
---|
693 | if (m_state != read_write_lock_state::unlocked) |
---|
694 | unlock(); |
---|
695 | } |
---|
696 | |
---|
697 | void read_lock() |
---|
698 | { |
---|
699 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
700 | read_write_lock_ops<TimedReadWriteMutex>::read_lock(m_mutex); |
---|
701 | m_state = read_write_lock_state::read_locked; |
---|
702 | } |
---|
703 | |
---|
704 | bool try_read_lock() |
---|
705 | { |
---|
706 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
707 | if(read_write_lock_ops<TimedReadWriteMutex>::try_read_lock(m_mutex)) |
---|
708 | { |
---|
709 | m_state = read_write_lock_state::read_locked; |
---|
710 | return true; |
---|
711 | } |
---|
712 | return false; |
---|
713 | } |
---|
714 | |
---|
715 | bool timed_read_lock(const xtime &xt) |
---|
716 | { |
---|
717 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
718 | if(read_write_lock_ops<TimedReadWriteMutex>::timed_read_lock(m_mutex,xt)) |
---|
719 | { |
---|
720 | m_state = read_write_lock_state::read_locked; |
---|
721 | return true; |
---|
722 | } |
---|
723 | return false; |
---|
724 | } |
---|
725 | |
---|
726 | void write_lock() |
---|
727 | { |
---|
728 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
729 | read_write_lock_ops<TimedReadWriteMutex>::write_lock(m_mutex); |
---|
730 | m_state = read_write_lock_state::write_locked; |
---|
731 | } |
---|
732 | |
---|
733 | bool try_write_lock() |
---|
734 | { |
---|
735 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
736 | if(read_write_lock_ops<TimedReadWriteMutex>::try_write_lock(m_mutex)) |
---|
737 | { |
---|
738 | m_state = read_write_lock_state::write_locked; |
---|
739 | return true; |
---|
740 | } |
---|
741 | return false; |
---|
742 | } |
---|
743 | |
---|
744 | bool timed_write_lock(const xtime &xt) |
---|
745 | { |
---|
746 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
747 | if(read_write_lock_ops<TimedReadWriteMutex>::timed_write_lock(m_mutex,xt)) |
---|
748 | { |
---|
749 | m_state = read_write_lock_state::write_locked; |
---|
750 | return true; |
---|
751 | } |
---|
752 | return false; |
---|
753 | } |
---|
754 | |
---|
755 | void unlock() |
---|
756 | { |
---|
757 | if (m_state == read_write_lock_state::unlocked) throw lock_error(); |
---|
758 | if (m_state == read_write_lock_state::read_locked) |
---|
759 | read_write_lock_ops<TimedReadWriteMutex>::read_unlock(m_mutex); |
---|
760 | else //(m_state == read_write_lock_state::write_locked) |
---|
761 | read_write_lock_ops<TimedReadWriteMutex>::write_unlock(m_mutex); |
---|
762 | |
---|
763 | m_state = read_write_lock_state::unlocked; |
---|
764 | } |
---|
765 | |
---|
766 | void demote(void) |
---|
767 | { |
---|
768 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
769 | read_write_lock_ops<TimedReadWriteMutex>::demote(m_mutex); |
---|
770 | m_state = read_write_lock_state::read_locked; |
---|
771 | } |
---|
772 | |
---|
773 | bool try_demote(void) |
---|
774 | { |
---|
775 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
776 | return read_write_lock_ops<TimedReadWriteMutex>::try_demote(m_mutex) ? (m_state = read_write_lock_state::read_locked, true) : false; |
---|
777 | } |
---|
778 | |
---|
779 | bool timed_demote(const xtime &xt) |
---|
780 | { |
---|
781 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
782 | return read_write_lock_ops<TimedReadWriteMutex>::timed_demote(m_mutex, xt) ? (m_state = read_write_lock_state::read_locked, true) : false; |
---|
783 | } |
---|
784 | |
---|
785 | void promote(void) |
---|
786 | { |
---|
787 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
788 | read_write_lock_ops<TimedReadWriteMutex>::promote(m_mutex); |
---|
789 | m_state = read_write_lock_state::write_locked; |
---|
790 | } |
---|
791 | |
---|
792 | bool try_promote(void) |
---|
793 | { |
---|
794 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
795 | return read_write_lock_ops<TimedReadWriteMutex>::try_promote(m_mutex) ? (m_state = read_write_lock_state::write_locked, true) : false; |
---|
796 | } |
---|
797 | |
---|
798 | bool timed_promote(const xtime &xt) |
---|
799 | { |
---|
800 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
801 | return read_write_lock_ops<TimedReadWriteMutex>::timed_promote(m_mutex, xt) ? (m_state = read_write_lock_state::write_locked, true) : false; |
---|
802 | } |
---|
803 | |
---|
804 | //If allow_unlock = true, set_lock always succeeds and |
---|
805 | //the function result indicates whether an unlock was required. |
---|
806 | //If allow_unlock = false, set_lock may fail; |
---|
807 | //the function result indicates whether it succeeded. |
---|
808 | bool set_lock(read_write_lock_state::read_write_lock_state_enum ls, bool allow_unlock = true) |
---|
809 | { |
---|
810 | bool result = !allow_unlock; |
---|
811 | |
---|
812 | if (m_state != ls) |
---|
813 | { |
---|
814 | if (m_state == read_write_lock_state::unlocked) |
---|
815 | { |
---|
816 | if (ls == read_write_lock_state::read_locked) |
---|
817 | read_lock(); |
---|
818 | else //(ls == read_write_lock_state::write_locked) |
---|
819 | write_lock(); |
---|
820 | } |
---|
821 | else //(m_state == read_write_lock_state::read_locked || m_state == read_write_lock_state::write_locked) |
---|
822 | { |
---|
823 | if (ls == read_write_lock_state::read_locked) |
---|
824 | demote(); |
---|
825 | else if (ls == read_write_lock_state::write_locked) |
---|
826 | { |
---|
827 | if (!try_promote()) |
---|
828 | { |
---|
829 | if (allow_unlock) |
---|
830 | { |
---|
831 | result = true; |
---|
832 | unlock(); |
---|
833 | write_lock(); |
---|
834 | } |
---|
835 | else |
---|
836 | result = false; |
---|
837 | } |
---|
838 | } |
---|
839 | else //(ls == read_write_lock_state::unlocked) |
---|
840 | unlock(); |
---|
841 | } |
---|
842 | } |
---|
843 | |
---|
844 | return result; |
---|
845 | } |
---|
846 | |
---|
847 | bool try_set_lock(read_write_lock_state::read_write_lock_state_enum ls) |
---|
848 | { |
---|
849 | if (m_state != ls) |
---|
850 | { |
---|
851 | if (m_state == read_write_lock_state::unlocked) |
---|
852 | { |
---|
853 | if (ls == read_write_lock_state::read_locked) |
---|
854 | return try_read_lock(); |
---|
855 | else // (ls == read_write_lock_state::write_locked) |
---|
856 | return try_write_lock(); |
---|
857 | } |
---|
858 | else //(m_state == read_write_lock_state::read_locked || m_state == read_write_lock_state::write_locked) |
---|
859 | { |
---|
860 | if (ls == read_write_lock_state::read_locked) |
---|
861 | return try_demote(); |
---|
862 | else if (ls == read_write_lock_state::write_locked) |
---|
863 | return try_promote(); |
---|
864 | else //(ls == read_write_lock_state::unlocked) |
---|
865 | return unlock(), true; |
---|
866 | } |
---|
867 | } |
---|
868 | else //(m_state == ls) |
---|
869 | return true; |
---|
870 | } |
---|
871 | |
---|
872 | bool timed_set_lock(read_write_lock_state::read_write_lock_state_enum ls, const xtime &xt) |
---|
873 | { |
---|
874 | if (m_state != ls) |
---|
875 | { |
---|
876 | if (m_state == read_write_lock_state::unlocked) |
---|
877 | { |
---|
878 | if (ls == read_write_lock_state::read_locked) |
---|
879 | return timed_read_lock(xt); |
---|
880 | else // (ls == read_write_lock_state::write_locked) |
---|
881 | return timed_write_lock(xt); |
---|
882 | } |
---|
883 | else //(m_state == read_write_lock_state::read_locked || m_state == read_write_lock_state::write_locked) |
---|
884 | { |
---|
885 | if (ls == read_write_lock_state::read_locked) |
---|
886 | return timed_demote(xt); |
---|
887 | else if (ls == read_write_lock_state::write_locked) |
---|
888 | return timed_promote(xt); |
---|
889 | else //(ls == read_write_lock_state::unlocked) |
---|
890 | return unlock(), true; |
---|
891 | } |
---|
892 | } |
---|
893 | else //(m_state == ls) |
---|
894 | return true; |
---|
895 | } |
---|
896 | |
---|
897 | bool locked() const |
---|
898 | { |
---|
899 | return m_state != read_write_lock_state::unlocked; |
---|
900 | } |
---|
901 | |
---|
902 | bool read_locked() const |
---|
903 | { |
---|
904 | return m_state == read_write_lock_state::read_locked; |
---|
905 | } |
---|
906 | |
---|
907 | bool write_locked() const |
---|
908 | { |
---|
909 | return m_state != read_write_lock_state::write_locked; |
---|
910 | } |
---|
911 | |
---|
912 | operator const void*() const |
---|
913 | { |
---|
914 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
915 | } |
---|
916 | |
---|
917 | read_write_lock_state::read_write_lock_state_enum state() const |
---|
918 | { |
---|
919 | return m_state; |
---|
920 | } |
---|
921 | |
---|
922 | private: |
---|
923 | |
---|
924 | TimedReadWriteMutex& m_mutex; |
---|
925 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
926 | }; |
---|
927 | |
---|
928 | template <typename TimedReadWriteMutex> |
---|
929 | class scoped_timed_read_lock : private noncopyable |
---|
930 | { |
---|
931 | public: |
---|
932 | |
---|
933 | typedef TimedReadWriteMutex mutex_type; |
---|
934 | |
---|
935 | explicit scoped_timed_read_lock( |
---|
936 | TimedReadWriteMutex& mx, |
---|
937 | bool initially_locked = true) |
---|
938 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
939 | { |
---|
940 | if (initially_locked) |
---|
941 | lock(); |
---|
942 | } |
---|
943 | |
---|
944 | ~scoped_timed_read_lock() |
---|
945 | { |
---|
946 | if (m_state != read_write_lock_state::unlocked) |
---|
947 | unlock(); |
---|
948 | } |
---|
949 | |
---|
950 | void lock() |
---|
951 | { |
---|
952 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
953 | read_write_lock_ops<TimedReadWriteMutex>::read_lock(m_mutex); |
---|
954 | m_state = read_write_lock_state::read_locked; |
---|
955 | } |
---|
956 | |
---|
957 | bool try_lock() |
---|
958 | { |
---|
959 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
960 | if(read_write_lock_ops<TimedReadWriteMutex>::try_read_lock(m_mutex)) |
---|
961 | { |
---|
962 | m_state = read_write_lock_state::read_locked; |
---|
963 | return true; |
---|
964 | } |
---|
965 | return false; |
---|
966 | } |
---|
967 | |
---|
968 | bool timed_lock(const xtime &xt) |
---|
969 | { |
---|
970 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
971 | if(read_write_lock_ops<TimedReadWriteMutex>::timed_read_lock(m_mutex,xt)) |
---|
972 | { |
---|
973 | m_state = read_write_lock_state::read_locked; |
---|
974 | return true; |
---|
975 | } |
---|
976 | return false; |
---|
977 | } |
---|
978 | |
---|
979 | void unlock() |
---|
980 | { |
---|
981 | if (m_state != read_write_lock_state::read_locked) throw lock_error(); |
---|
982 | read_write_lock_ops<TimedReadWriteMutex>::read_unlock(m_mutex); |
---|
983 | |
---|
984 | m_state = read_write_lock_state::unlocked; |
---|
985 | } |
---|
986 | |
---|
987 | bool locked() const |
---|
988 | { |
---|
989 | return m_state != read_write_lock_state::unlocked; |
---|
990 | } |
---|
991 | |
---|
992 | operator const void*() const |
---|
993 | { |
---|
994 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
995 | } |
---|
996 | |
---|
997 | read_write_lock_state::read_write_lock_state_enum state() const |
---|
998 | { |
---|
999 | return m_state; |
---|
1000 | } |
---|
1001 | |
---|
1002 | private: |
---|
1003 | |
---|
1004 | TimedReadWriteMutex& m_mutex; |
---|
1005 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
1006 | }; |
---|
1007 | |
---|
1008 | template <typename TimedReadWriteMutex> |
---|
1009 | class scoped_timed_write_lock : private noncopyable |
---|
1010 | { |
---|
1011 | public: |
---|
1012 | |
---|
1013 | typedef TimedReadWriteMutex mutex_type; |
---|
1014 | |
---|
1015 | explicit scoped_timed_write_lock( |
---|
1016 | TimedReadWriteMutex& mx, |
---|
1017 | bool initially_locked = true) |
---|
1018 | : m_mutex(mx), m_state(read_write_lock_state::unlocked) |
---|
1019 | { |
---|
1020 | if (initially_locked) |
---|
1021 | lock(); |
---|
1022 | } |
---|
1023 | |
---|
1024 | ~scoped_timed_write_lock() |
---|
1025 | { |
---|
1026 | if (m_state != read_write_lock_state::unlocked) |
---|
1027 | unlock(); |
---|
1028 | } |
---|
1029 | |
---|
1030 | void lock() |
---|
1031 | { |
---|
1032 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
1033 | read_write_lock_ops<TimedReadWriteMutex>::write_lock(m_mutex); |
---|
1034 | m_state = read_write_lock_state::write_locked; |
---|
1035 | } |
---|
1036 | |
---|
1037 | bool try_lock() |
---|
1038 | { |
---|
1039 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
1040 | if(read_write_lock_ops<TimedReadWriteMutex>::try_write_lock(m_mutex)) |
---|
1041 | { |
---|
1042 | m_state = read_write_lock_state::write_locked; |
---|
1043 | return true; |
---|
1044 | } |
---|
1045 | return false; |
---|
1046 | } |
---|
1047 | |
---|
1048 | bool timed_lock(const xtime &xt) |
---|
1049 | { |
---|
1050 | if (m_state != read_write_lock_state::unlocked) throw lock_error(); |
---|
1051 | if(read_write_lock_ops<TimedReadWriteMutex>::timed_write_lock(m_mutex,xt)) |
---|
1052 | { |
---|
1053 | m_state = read_write_lock_state::write_locked; |
---|
1054 | return true; |
---|
1055 | } |
---|
1056 | return false; |
---|
1057 | } |
---|
1058 | |
---|
1059 | void unlock() |
---|
1060 | { |
---|
1061 | if (m_state != read_write_lock_state::write_locked) throw lock_error(); |
---|
1062 | read_write_lock_ops<TimedReadWriteMutex>::write_unlock(m_mutex); |
---|
1063 | |
---|
1064 | m_state = read_write_lock_state::unlocked; |
---|
1065 | } |
---|
1066 | |
---|
1067 | bool locked() const |
---|
1068 | { |
---|
1069 | return m_state != read_write_lock_state::unlocked; |
---|
1070 | } |
---|
1071 | |
---|
1072 | operator const void*() const |
---|
1073 | { |
---|
1074 | return (m_state != read_write_lock_state::unlocked) ? this : 0; |
---|
1075 | } |
---|
1076 | |
---|
1077 | read_write_lock_state::read_write_lock_state_enum state() const |
---|
1078 | { |
---|
1079 | return m_state; |
---|
1080 | } |
---|
1081 | |
---|
1082 | private: |
---|
1083 | |
---|
1084 | TimedReadWriteMutex& m_mutex; |
---|
1085 | read_write_lock_state::read_write_lock_state_enum m_state; |
---|
1086 | }; |
---|
1087 | |
---|
1088 | } // namespace thread |
---|
1089 | } // namespace detail |
---|
1090 | } // namespace boost |
---|
1091 | |
---|
1092 | #endif |
---|
1093 | |
---|
1094 | // Change Log: |
---|
1095 | // 10 Mar 02 |
---|
1096 | // Original version. |
---|
1097 | // 4 May 04 GlassfordM |
---|
1098 | // Implement lock promotion and demotion (add member functions demote(), |
---|
1099 | // try_demote(), timed_demote(), try_promote(), timed_promote(); note |
---|
1100 | // that there is intentionally no promote() member function). |
---|
1101 | // Add set_lock() member function. |
---|
1102 | // Change try lock & timed lock constructor parameters for consistency. |
---|
1103 | // Rename to improve consistency and eliminate abbreviations: |
---|
1104 | // Use "read" and "write" instead of "shared" and "exclusive". |
---|
1105 | // Change "rd" to "read", "wr" to "write", "rw" to "read_write". |
---|
1106 | // Add mutex_type typdef. |
---|