1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-threads.h D-Bus threads handling
3 *
4 * Copyright (C) 2002, 2003, 2006 Red Hat Inc.
5 *
6 * Licensed under the Academic Free License version 2.1
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23 #include <config.h>
24 #include "dbus-threads.h"
25 #include "dbus-internals.h"
26 #include "dbus-threads-internal.h"
27 #include "dbus-list.h"
28
29 static DBusThreadFunctions thread_functions =
30 {
31 0,
32 NULL, NULL, NULL, NULL, NULL,
33 NULL, NULL, NULL, NULL, NULL,
34 NULL, NULL, NULL, NULL,
35
36 NULL, NULL, NULL, NULL
37 };
38
39 static int thread_init_generation = 0;
40
41 static DBusList *uninitialized_mutex_list = NULL;
42 static DBusList *uninitialized_condvar_list = NULL;
43
44 /** This is used for the no-op default mutex pointer, just to be distinct from #NULL */
45 #define _DBUS_DUMMY_MUTEX ((DBusMutex*)0xABCDEF)
46
47 /** This is used for the no-op default mutex pointer, just to be distinct from #NULL */
48 #define _DBUS_DUMMY_CONDVAR ((DBusCondVar*)0xABCDEF2)
49
50 /**
51 * @defgroup DBusThreadsInternals Thread functions
52 * @ingroup DBusInternals
53 * @brief _dbus_mutex_lock(), etc.
54 *
55 * Functions and macros related to threads and thread locks.
56 *
57 * @{
58 */
59
60 /**
61 * Creates a new mutex using the function supplied to dbus_threads_init(),
62 * or creates a no-op mutex if threads are not initialized.
63 * May return #NULL even if threads are initialized, indicating
64 * out-of-memory.
65 *
66 * @returns new mutex or #NULL
67 */
68 DBusMutex*
_dbus_mutex_new(void)69 _dbus_mutex_new (void)
70 {
71 if (thread_functions.recursive_mutex_new)
72 return (* thread_functions.recursive_mutex_new) ();
73 else if (thread_functions.mutex_new)
74 return (* thread_functions.mutex_new) ();
75 else
76 return _DBUS_DUMMY_MUTEX;
77 }
78
79 /**
80 * This does the same thing as _dbus_mutex_new. It however
81 * gives another level of indirection by allocating a pointer
82 * to point to the mutex location. This allows the threading
83 * module to swap out dummy mutexes for real a real mutex so libraries
84 * can initialize threads even after the D-Bus API has been used.
85 *
86 * @param location_p the location of the new mutex, can return #NULL on OOM
87 */
88 void
_dbus_mutex_new_at_location(DBusMutex ** location_p)89 _dbus_mutex_new_at_location (DBusMutex **location_p)
90 {
91 _dbus_assert (location_p != NULL);
92
93 *location_p = _dbus_mutex_new();
94
95 if (thread_init_generation != _dbus_current_generation && *location_p)
96 {
97 if (!_dbus_list_append (&uninitialized_mutex_list, location_p))
98 {
99 _dbus_mutex_free (*location_p);
100 *location_p = NULL;
101 }
102 }
103 }
104
105 /**
106 * Frees a mutex created with dbus_mutex_new(); does
107 * nothing if passed a #NULL pointer.
108 */
109 void
_dbus_mutex_free(DBusMutex * mutex)110 _dbus_mutex_free (DBusMutex *mutex)
111 {
112 if (mutex)
113 {
114 if (mutex && thread_functions.recursive_mutex_free)
115 (* thread_functions.recursive_mutex_free) (mutex);
116 else if (mutex && thread_functions.mutex_free)
117 (* thread_functions.mutex_free) (mutex);
118 }
119 }
120
121 /**
122 * Frees a mutex and removes it from the
123 * uninitialized_mutex_list;
124 * does nothing if passed a #NULL pointer.
125 */
126 void
_dbus_mutex_free_at_location(DBusMutex ** location_p)127 _dbus_mutex_free_at_location (DBusMutex **location_p)
128 {
129 if (location_p)
130 {
131 if (thread_init_generation != _dbus_current_generation)
132 _dbus_list_remove (&uninitialized_mutex_list, location_p);
133
134 _dbus_mutex_free (*location_p);
135 }
136 }
137
138 /**
139 * Locks a mutex. Does nothing if passed a #NULL pointer.
140 * Locks may be recursive if threading implementation initialized
141 * recursive locks.
142 */
143 void
_dbus_mutex_lock(DBusMutex * mutex)144 _dbus_mutex_lock (DBusMutex *mutex)
145 {
146 if (mutex)
147 {
148 if (thread_functions.recursive_mutex_lock)
149 (* thread_functions.recursive_mutex_lock) (mutex);
150 else if (thread_functions.mutex_lock)
151 (* thread_functions.mutex_lock) (mutex);
152 }
153 }
154
155 /**
156 * Unlocks a mutex. Does nothing if passed a #NULL pointer.
157 *
158 * @returns #TRUE on success
159 */
160 void
_dbus_mutex_unlock(DBusMutex * mutex)161 _dbus_mutex_unlock (DBusMutex *mutex)
162 {
163 if (mutex)
164 {
165 if (thread_functions.recursive_mutex_unlock)
166 (* thread_functions.recursive_mutex_unlock) (mutex);
167 else if (thread_functions.mutex_unlock)
168 (* thread_functions.mutex_unlock) (mutex);
169 }
170 }
171
172 /**
173 * Creates a new condition variable using the function supplied
174 * to dbus_threads_init(), or creates a no-op condition variable
175 * if threads are not initialized. May return #NULL even if
176 * threads are initialized, indicating out-of-memory.
177 *
178 * @returns new mutex or #NULL
179 */
180 DBusCondVar *
_dbus_condvar_new(void)181 _dbus_condvar_new (void)
182 {
183 if (thread_functions.condvar_new)
184 return (* thread_functions.condvar_new) ();
185 else
186 return _DBUS_DUMMY_CONDVAR;
187 }
188
189
190 /**
191 * This does the same thing as _dbus_condvar_new. It however
192 * gives another level of indirection by allocating a pointer
193 * to point to the condvar location. This allows the threading
194 * module to swap out dummy condvars for real a real condvar so libraries
195 * can initialize threads even after the D-Bus API has been used.
196 *
197 * @returns the location of a new condvar or #NULL on OOM
198 */
199
200 void
_dbus_condvar_new_at_location(DBusCondVar ** location_p)201 _dbus_condvar_new_at_location (DBusCondVar **location_p)
202 {
203 *location_p = _dbus_condvar_new();
204
205 if (thread_init_generation != _dbus_current_generation && *location_p)
206 {
207 if (!_dbus_list_append (&uninitialized_condvar_list, location_p))
208 {
209 _dbus_condvar_free (*location_p);
210 *location_p = NULL;
211 }
212 }
213 }
214
215
216 /**
217 * Frees a conditional variable created with dbus_condvar_new(); does
218 * nothing if passed a #NULL pointer.
219 */
220 void
_dbus_condvar_free(DBusCondVar * cond)221 _dbus_condvar_free (DBusCondVar *cond)
222 {
223 if (cond && thread_functions.condvar_free)
224 (* thread_functions.condvar_free) (cond);
225 }
226
227 /**
228 * Frees a conditional variable and removes it from the
229 * uninitialized_condvar_list;
230 * does nothing if passed a #NULL pointer.
231 */
232 void
_dbus_condvar_free_at_location(DBusCondVar ** location_p)233 _dbus_condvar_free_at_location (DBusCondVar **location_p)
234 {
235 if (location_p)
236 {
237 if (thread_init_generation != _dbus_current_generation)
238 _dbus_list_remove (&uninitialized_condvar_list, location_p);
239
240 _dbus_condvar_free (*location_p);
241 }
242 }
243
244 /**
245 * Atomically unlocks the mutex and waits for the conditions
246 * variable to be signalled. Locks the mutex again before
247 * returning.
248 * Does nothing if passed a #NULL pointer.
249 */
250 void
_dbus_condvar_wait(DBusCondVar * cond,DBusMutex * mutex)251 _dbus_condvar_wait (DBusCondVar *cond,
252 DBusMutex *mutex)
253 {
254 if (cond && mutex && thread_functions.condvar_wait)
255 (* thread_functions.condvar_wait) (cond, mutex);
256 }
257
258 /**
259 * Atomically unlocks the mutex and waits for the conditions variable
260 * to be signalled, or for a timeout. Locks the mutex again before
261 * returning. Does nothing if passed a #NULL pointer. Return value
262 * is #FALSE if we timed out, #TRUE otherwise.
263 *
264 * @param cond the condition variable
265 * @param mutex the mutex
266 * @param timeout_milliseconds the maximum time to wait
267 * @returns #FALSE if the timeout occurred, #TRUE if not
268 */
269 dbus_bool_t
_dbus_condvar_wait_timeout(DBusCondVar * cond,DBusMutex * mutex,int timeout_milliseconds)270 _dbus_condvar_wait_timeout (DBusCondVar *cond,
271 DBusMutex *mutex,
272 int timeout_milliseconds)
273 {
274 if (cond && mutex && thread_functions.condvar_wait)
275 return (* thread_functions.condvar_wait_timeout) (cond, mutex, timeout_milliseconds);
276 else
277 return TRUE;
278 }
279
280 /**
281 * If there are threads waiting on the condition variable, wake
282 * up exactly one.
283 * Does nothing if passed a #NULL pointer.
284 */
285 void
_dbus_condvar_wake_one(DBusCondVar * cond)286 _dbus_condvar_wake_one (DBusCondVar *cond)
287 {
288 if (cond && thread_functions.condvar_wake_one)
289 (* thread_functions.condvar_wake_one) (cond);
290 }
291
292 /**
293 * If there are threads waiting on the condition variable, wake
294 * up all of them.
295 * Does nothing if passed a #NULL pointer.
296 */
297 void
_dbus_condvar_wake_all(DBusCondVar * cond)298 _dbus_condvar_wake_all (DBusCondVar *cond)
299 {
300 if (cond && thread_functions.condvar_wake_all)
301 (* thread_functions.condvar_wake_all) (cond);
302 }
303
304 static void
shutdown_global_locks(void * data)305 shutdown_global_locks (void *data)
306 {
307 DBusMutex ***locks = data;
308 int i;
309
310 i = 0;
311 while (i < _DBUS_N_GLOBAL_LOCKS)
312 {
313 _dbus_mutex_free (*(locks[i]));
314 *(locks[i]) = NULL;
315 ++i;
316 }
317
318 dbus_free (locks);
319 }
320
321 static void
shutdown_uninitialized_locks(void * data)322 shutdown_uninitialized_locks (void *data)
323 {
324 _dbus_list_clear (&uninitialized_mutex_list);
325 _dbus_list_clear (&uninitialized_condvar_list);
326 }
327
328 static dbus_bool_t
init_uninitialized_locks(void)329 init_uninitialized_locks (void)
330 {
331 DBusList *link;
332
333 _dbus_assert (thread_init_generation != _dbus_current_generation);
334
335 link = uninitialized_mutex_list;
336 while (link != NULL)
337 {
338 DBusMutex **mp;
339
340 mp = (DBusMutex **)link->data;
341 _dbus_assert (*mp == _DBUS_DUMMY_MUTEX);
342
343 *mp = _dbus_mutex_new ();
344 if (*mp == NULL)
345 goto fail_mutex;
346
347 link = _dbus_list_get_next_link (&uninitialized_mutex_list, link);
348 }
349
350 link = uninitialized_condvar_list;
351 while (link != NULL)
352 {
353 DBusCondVar **cp;
354
355 cp = (DBusCondVar **)link->data;
356 _dbus_assert (*cp == _DBUS_DUMMY_CONDVAR);
357
358 *cp = _dbus_condvar_new ();
359 if (*cp == NULL)
360 goto fail_condvar;
361
362 link = _dbus_list_get_next_link (&uninitialized_condvar_list, link);
363 }
364
365 _dbus_list_clear (&uninitialized_mutex_list);
366 _dbus_list_clear (&uninitialized_condvar_list);
367
368 if (!_dbus_register_shutdown_func (shutdown_uninitialized_locks,
369 NULL))
370 goto fail_condvar;
371
372 return TRUE;
373
374 fail_condvar:
375 link = uninitialized_condvar_list;
376 while (link != NULL)
377 {
378 DBusCondVar **cp;
379
380 cp = (DBusCondVar **)link->data;
381
382 if (*cp != _DBUS_DUMMY_CONDVAR)
383 _dbus_condvar_free (*cp);
384 else
385 break;
386
387 *cp = _DBUS_DUMMY_CONDVAR;
388
389 link = _dbus_list_get_next_link (&uninitialized_condvar_list, link);
390 }
391
392 fail_mutex:
393 link = uninitialized_mutex_list;
394 while (link != NULL)
395 {
396 DBusMutex **mp;
397
398 mp = (DBusMutex **)link->data;
399
400 if (*mp != _DBUS_DUMMY_MUTEX)
401 _dbus_mutex_free (*mp);
402 else
403 break;
404
405 *mp = _DBUS_DUMMY_MUTEX;
406
407 link = _dbus_list_get_next_link (&uninitialized_mutex_list, link);
408 }
409
410 return FALSE;
411 }
412
413 static dbus_bool_t
init_locks(void)414 init_locks (void)
415 {
416 int i;
417 DBusMutex ***dynamic_global_locks;
418
419 DBusMutex **global_locks[] = {
420 #define LOCK_ADDR(name) (& _dbus_lock_##name)
421 LOCK_ADDR (win_fds),
422 LOCK_ADDR (sid_atom_cache),
423 LOCK_ADDR (list),
424 LOCK_ADDR (connection_slots),
425 LOCK_ADDR (pending_call_slots),
426 LOCK_ADDR (server_slots),
427 LOCK_ADDR (message_slots),
428 #if !DBUS_USE_SYNC
429 LOCK_ADDR (atomic),
430 #endif
431 LOCK_ADDR (bus),
432 LOCK_ADDR (bus_datas),
433 LOCK_ADDR (shutdown_funcs),
434 LOCK_ADDR (system_users),
435 LOCK_ADDR (message_cache),
436 LOCK_ADDR (shared_connections),
437 LOCK_ADDR (machine_uuid)
438 #undef LOCK_ADDR
439 };
440
441 _dbus_assert (_DBUS_N_ELEMENTS (global_locks) ==
442 _DBUS_N_GLOBAL_LOCKS);
443
444 i = 0;
445
446 dynamic_global_locks = dbus_new (DBusMutex**, _DBUS_N_GLOBAL_LOCKS);
447 if (dynamic_global_locks == NULL)
448 goto failed;
449
450 while (i < _DBUS_N_ELEMENTS (global_locks))
451 {
452 *global_locks[i] = _dbus_mutex_new ();
453
454 if (*global_locks[i] == NULL)
455 goto failed;
456
457 dynamic_global_locks[i] = global_locks[i];
458
459 ++i;
460 }
461
462 if (!_dbus_register_shutdown_func (shutdown_global_locks,
463 dynamic_global_locks))
464 goto failed;
465
466 if (!init_uninitialized_locks ())
467 goto failed;
468
469 return TRUE;
470
471 failed:
472 dbus_free (dynamic_global_locks);
473
474 for (i = i - 1; i >= 0; i--)
475 {
476 _dbus_mutex_free (*global_locks[i]);
477 *global_locks[i] = NULL;
478 }
479 return FALSE;
480 }
481
482 /** @} */ /* end of internals */
483
484 /**
485 * @defgroup DBusThreads Thread functions
486 * @ingroup DBus
487 * @brief dbus_threads_init() and dbus_threads_init_default()
488 *
489 * Functions and macros related to threads and thread locks.
490 *
491 * If threads are initialized, the D-Bus library has locks on all
492 * global data structures. In addition, each #DBusConnection has a
493 * lock, so only one thread at a time can touch the connection. (See
494 * @ref DBusConnection for more on connection locking.)
495 *
496 * Most other objects, however, do not have locks - they can only be
497 * used from a single thread at a time, unless you lock them yourself.
498 * For example, a #DBusMessage can't be modified from two threads
499 * at once.
500 *
501 * @{
502 */
503
504 /**
505 *
506 * Initializes threads. If this function is not called, the D-Bus
507 * library will not lock any data structures. If it is called, D-Bus
508 * will do locking, at some cost in efficiency. Note that this
509 * function must be called BEFORE the second thread is started.
510 *
511 * Almost always, you should use dbus_threads_init_default() instead.
512 * The raw dbus_threads_init() is only useful if you require a
513 * particular thread implementation for some reason.
514 *
515 * A possible reason to use dbus_threads_init() rather than
516 * dbus_threads_init_default() is to insert debugging checks or print
517 * statements.
518 *
519 * dbus_threads_init() may be called more than once. The first one
520 * wins and subsequent calls are ignored. (Unless you use
521 * dbus_shutdown() to reset libdbus, which will let you re-init
522 * threads.)
523 *
524 * Either recursive or nonrecursive mutex functions must be specified,
525 * but not both. New code should provide only the recursive functions
526 * - specifying the nonrecursive ones is deprecated.
527 *
528 * Because this function effectively sets global state, all code
529 * running in a given application must agree on the thread
530 * implementation. Most code won't care which thread implementation is
531 * used, so there's no problem. However, usually libraries should not
532 * call dbus_threads_init() or dbus_threads_init_default(), instead
533 * leaving this policy choice to applications.
534 *
535 * The exception is for application frameworks (GLib, Qt, etc.) and
536 * D-Bus bindings based on application frameworks. These frameworks
537 * define a cross-platform thread abstraction and can assume
538 * applications using the framework are OK with using that thread
539 * abstraction.
540 *
541 * However, even these app frameworks may find it easier to simply call
542 * dbus_threads_init_default(), and there's no reason they shouldn't.
543 *
544 * @param functions functions for using threads
545 * @returns #TRUE on success, #FALSE if no memory
546 */
547 dbus_bool_t
dbus_threads_init(const DBusThreadFunctions * functions)548 dbus_threads_init (const DBusThreadFunctions *functions)
549 {
550 dbus_bool_t mutex_set;
551 dbus_bool_t recursive_mutex_set;
552
553 _dbus_assert (functions != NULL);
554
555 /* these base functions are required. Future additions to
556 * DBusThreadFunctions may be optional.
557 */
558 _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_NEW_MASK);
559 _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_FREE_MASK);
560 _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_MASK);
561 _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK);
562 _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK);
563 _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK);
564 _dbus_assert (functions->condvar_new != NULL);
565 _dbus_assert (functions->condvar_free != NULL);
566 _dbus_assert (functions->condvar_wait != NULL);
567 _dbus_assert (functions->condvar_wait_timeout != NULL);
568 _dbus_assert (functions->condvar_wake_one != NULL);
569 _dbus_assert (functions->condvar_wake_all != NULL);
570
571 /* Either the mutex function set or recursive mutex set needs
572 * to be available but not both
573 */
574 mutex_set = (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_NEW_MASK) &&
575 (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_FREE_MASK) &&
576 (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_LOCK_MASK) &&
577 (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_UNLOCK_MASK) &&
578 functions->mutex_new &&
579 functions->mutex_free &&
580 functions->mutex_lock &&
581 functions->mutex_unlock;
582
583 recursive_mutex_set =
584 (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK) &&
585 (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK) &&
586 (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK) &&
587 (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK) &&
588 functions->recursive_mutex_new &&
589 functions->recursive_mutex_free &&
590 functions->recursive_mutex_lock &&
591 functions->recursive_mutex_unlock;
592
593 if (!(mutex_set || recursive_mutex_set))
594 _dbus_assert_not_reached ("Either the nonrecusrive or recursive mutex "
595 "functions sets should be passed into "
596 "dbus_threads_init. Neither sets were passed.");
597
598 if (mutex_set && recursive_mutex_set)
599 _dbus_assert_not_reached ("Either the nonrecusrive or recursive mutex "
600 "functions sets should be passed into "
601 "dbus_threads_init. Both sets were passed. "
602 "You most likely just want to set the recursive "
603 "mutex functions to avoid deadlocks in D-Bus.");
604
605 /* Check that all bits in the mask actually are valid mask bits.
606 * ensures people won't write code that breaks when we add
607 * new bits.
608 */
609 _dbus_assert ((functions->mask & ~DBUS_THREAD_FUNCTIONS_ALL_MASK) == 0);
610
611 if (thread_init_generation != _dbus_current_generation)
612 thread_functions.mask = 0; /* allow re-init in new generation */
613
614 /* Silently allow multiple init
615 * First init wins and D-Bus will always use its threading system
616 */
617 if (thread_functions.mask != 0)
618 return TRUE;
619
620 thread_functions.mutex_new = functions->mutex_new;
621 thread_functions.mutex_free = functions->mutex_free;
622 thread_functions.mutex_lock = functions->mutex_lock;
623 thread_functions.mutex_unlock = functions->mutex_unlock;
624
625 thread_functions.condvar_new = functions->condvar_new;
626 thread_functions.condvar_free = functions->condvar_free;
627 thread_functions.condvar_wait = functions->condvar_wait;
628 thread_functions.condvar_wait_timeout = functions->condvar_wait_timeout;
629 thread_functions.condvar_wake_one = functions->condvar_wake_one;
630 thread_functions.condvar_wake_all = functions->condvar_wake_all;
631
632 if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK)
633 thread_functions.recursive_mutex_new = functions->recursive_mutex_new;
634
635 if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK)
636 thread_functions.recursive_mutex_free = functions->recursive_mutex_free;
637
638 if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK)
639 thread_functions.recursive_mutex_lock = functions->recursive_mutex_lock;
640
641 if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK)
642 thread_functions.recursive_mutex_unlock = functions->recursive_mutex_unlock;
643
644 thread_functions.mask = functions->mask;
645
646 if (!init_locks ())
647 return FALSE;
648
649 thread_init_generation = _dbus_current_generation;
650
651 return TRUE;
652 }
653
654
655
656 /* Default thread implemenation */
657
658 /**
659 *
660 * Calls dbus_threads_init() with a default set of
661 * #DBusThreadFunctions appropriate for the platform.
662 *
663 * Most applications should use this rather than dbus_threads_init().
664 *
665 * It's safe to call dbus_threads_init_default() as many times as you
666 * want, but only the first time will have an effect.
667 *
668 * dbus_shutdown() reverses the effects of this function when it
669 * resets all global state in libdbus.
670 *
671 * @returns #TRUE on success, #FALSE if not enough memory
672 */
673 dbus_bool_t
dbus_threads_init_default(void)674 dbus_threads_init_default (void)
675 {
676 return _dbus_threads_init_platform_specific ();
677 }
678
679
680 /** @} */
681
682 #ifdef DBUS_BUILD_TESTS
683 /** Fake mutex used for debugging */
684 typedef struct DBusFakeMutex DBusFakeMutex;
685 /** Fake mutex used for debugging */
686 struct DBusFakeMutex
687 {
688 dbus_bool_t locked; /**< Mutex is "locked" */
689 };
690
691 static DBusMutex * dbus_fake_mutex_new (void);
692 static void dbus_fake_mutex_free (DBusMutex *mutex);
693 static dbus_bool_t dbus_fake_mutex_lock (DBusMutex *mutex);
694 static dbus_bool_t dbus_fake_mutex_unlock (DBusMutex *mutex);
695 static DBusCondVar* dbus_fake_condvar_new (void);
696 static void dbus_fake_condvar_free (DBusCondVar *cond);
697 static void dbus_fake_condvar_wait (DBusCondVar *cond,
698 DBusMutex *mutex);
699 static dbus_bool_t dbus_fake_condvar_wait_timeout (DBusCondVar *cond,
700 DBusMutex *mutex,
701 int timeout_msec);
702 static void dbus_fake_condvar_wake_one (DBusCondVar *cond);
703 static void dbus_fake_condvar_wake_all (DBusCondVar *cond);
704
705
706 static const DBusThreadFunctions fake_functions =
707 {
708 DBUS_THREAD_FUNCTIONS_MUTEX_NEW_MASK |
709 DBUS_THREAD_FUNCTIONS_MUTEX_FREE_MASK |
710 DBUS_THREAD_FUNCTIONS_MUTEX_LOCK_MASK |
711 DBUS_THREAD_FUNCTIONS_MUTEX_UNLOCK_MASK |
712 DBUS_THREAD_FUNCTIONS_CONDVAR_NEW_MASK |
713 DBUS_THREAD_FUNCTIONS_CONDVAR_FREE_MASK |
714 DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_MASK |
715 DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK |
716 DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK|
717 DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK,
718 dbus_fake_mutex_new,
719 dbus_fake_mutex_free,
720 dbus_fake_mutex_lock,
721 dbus_fake_mutex_unlock,
722 dbus_fake_condvar_new,
723 dbus_fake_condvar_free,
724 dbus_fake_condvar_wait,
725 dbus_fake_condvar_wait_timeout,
726 dbus_fake_condvar_wake_one,
727 dbus_fake_condvar_wake_all
728 };
729
730 static DBusMutex *
dbus_fake_mutex_new(void)731 dbus_fake_mutex_new (void)
732 {
733 DBusFakeMutex *mutex;
734
735 mutex = dbus_new0 (DBusFakeMutex, 1);
736
737 return (DBusMutex *)mutex;
738 }
739
740 static void
dbus_fake_mutex_free(DBusMutex * mutex)741 dbus_fake_mutex_free (DBusMutex *mutex)
742 {
743 DBusFakeMutex *fake = (DBusFakeMutex*) mutex;
744
745 _dbus_assert (!fake->locked);
746
747 dbus_free (fake);
748 }
749
750 static dbus_bool_t
dbus_fake_mutex_lock(DBusMutex * mutex)751 dbus_fake_mutex_lock (DBusMutex *mutex)
752 {
753 DBusFakeMutex *fake = (DBusFakeMutex*) mutex;
754
755 _dbus_assert (!fake->locked);
756
757 fake->locked = TRUE;
758
759 return TRUE;
760 }
761
762 static dbus_bool_t
dbus_fake_mutex_unlock(DBusMutex * mutex)763 dbus_fake_mutex_unlock (DBusMutex *mutex)
764 {
765 DBusFakeMutex *fake = (DBusFakeMutex*) mutex;
766
767 _dbus_assert (fake->locked);
768
769 fake->locked = FALSE;
770
771 return TRUE;
772 }
773
774 static DBusCondVar*
dbus_fake_condvar_new(void)775 dbus_fake_condvar_new (void)
776 {
777 return (DBusCondVar*) _dbus_strdup ("FakeCondvar");
778 }
779
780 static void
dbus_fake_condvar_free(DBusCondVar * cond)781 dbus_fake_condvar_free (DBusCondVar *cond)
782 {
783 dbus_free (cond);
784 }
785
786 static void
dbus_fake_condvar_wait(DBusCondVar * cond,DBusMutex * mutex)787 dbus_fake_condvar_wait (DBusCondVar *cond,
788 DBusMutex *mutex)
789 {
790
791 }
792
793 static dbus_bool_t
dbus_fake_condvar_wait_timeout(DBusCondVar * cond,DBusMutex * mutex,int timeout_msec)794 dbus_fake_condvar_wait_timeout (DBusCondVar *cond,
795 DBusMutex *mutex,
796 int timeout_msec)
797 {
798 return TRUE;
799 }
800
801 static void
dbus_fake_condvar_wake_one(DBusCondVar * cond)802 dbus_fake_condvar_wake_one (DBusCondVar *cond)
803 {
804
805 }
806
807 static void
dbus_fake_condvar_wake_all(DBusCondVar * cond)808 dbus_fake_condvar_wake_all (DBusCondVar *cond)
809 {
810
811 }
812
813 dbus_bool_t
_dbus_threads_init_debug(void)814 _dbus_threads_init_debug (void)
815 {
816 #ifdef DBUS_WIN
817 return _dbus_threads_init_platform_specific();
818 #else
819 return dbus_threads_init (&fake_functions);
820 #endif
821 }
822
823 #endif /* DBUS_BUILD_TESTS */
824