* include/vlc_threads.h,include/main.h,src/misc/threads.c,src/misc/win32_specific.c:
[vlc.git] / include / vlc_threads.h
1 /*****************************************************************************
2  * threads.h : threads implementation for the VideoLAN client
3  * This header provides a portable threads implementation.
4  *****************************************************************************
5  * Copyright (C) 1999, 2000 VideoLAN
6  * $Id: vlc_threads.h,v 1.6 2002/07/29 19:05:47 gbazin Exp $
7  *
8  * Authors: Jean-Marc Dressler <polux@via.ecp.fr>
9  *          Samuel Hocevar <sam@via.ecp.fr>
10  *          Gildas Bazin <gbazin@netcourrier.com>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  * 
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
25  *****************************************************************************/
26
27 #include <stdio.h>
28
29 #if defined(GPROF) || defined(DEBUG)
30 #   include <sys/time.h>
31 #endif
32
33 #if defined( PTH_INIT_IN_PTH_H )                                  /* GNU Pth */
34 #   include <pth.h>
35
36 #elif defined( ST_INIT_IN_ST_H )                            /* State threads */
37 #   include <st.h>
38
39 #elif defined( WIN32 )                                          /* Win32 API */
40 #   include <process.h>
41
42 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )  /* pthreads (like Linux & BSD) */
43 #   include <pthread.h>
44 #   ifdef DEBUG
45         /* Needed for pthread_cond_timedwait */
46 #       include <errno.h>
47 #   endif
48     /* This is not prototyped under Linux, though it exists. */
49     int pthread_mutexattr_setkind_np( pthread_mutexattr_t *attr, int kind );
50
51 #elif defined( HAVE_CTHREADS_H )                                  /* GNUMach */
52 #   include <cthreads.h>
53
54 #elif defined( HAVE_KERNEL_SCHEDULER_H )                             /* BeOS */
55 #   include <kernel/OS.h>
56 #   include <kernel/scheduler.h>
57 #   include <byteorder.h>
58
59 #else
60 #   error no threads available on your system !
61
62 #endif
63
64 /*****************************************************************************
65  * Constants
66  *****************************************************************************
67  * These constants are used by all threads in *_CreateThread() and
68  * *_DestroyThreads() functions. Since those calls are non-blocking, an integer
69  * value is used as a shared flag to represent the status of the thread.
70  *****************************************************************************/
71
72 /* Void status - this value can be used to make sure no operation is currently
73  * in progress on the concerned thread in an array of recorded threads */
74 #define THREAD_NOP          0                            /* nothing happened */
75
76 /* Creation status */
77 #define THREAD_CREATE       10                     /* thread is initializing */
78 #define THREAD_START        11                          /* thread has forked */
79 #define THREAD_READY        19                            /* thread is ready */
80
81 /* Destructions status */
82 #define THREAD_DESTROY      20            /* destruction order has been sent */
83 #define THREAD_END          21        /* destruction order has been received */
84 #define THREAD_OVER         29             /* thread does not exist any more */
85
86 /* Error status */
87 #define THREAD_ERROR        30                           /* an error occured */
88 #define THREAD_FATAL        31  /* an fatal error occured - program must end */
89
90 /*****************************************************************************
91  * Type definitions
92  *****************************************************************************/
93
94 #if defined( PTH_INIT_IN_PTH_H )
95 typedef pth_t            vlc_thread_t;
96 typedef pth_mutex_t      vlc_mutex_t;
97 typedef pth_cond_t       vlc_cond_t;
98
99 #elif defined( ST_INIT_IN_ST_H )
100 typedef st_thread_t *    vlc_thread_t;
101 typedef st_mutex_t *     vlc_mutex_t;
102 typedef st_cond_t *      vlc_cond_t;
103
104 #elif defined( WIN32 )
105 typedef HANDLE vlc_thread_t;
106 typedef BOOL (WINAPI *SIGNALOBJECTANDWAIT) ( HANDLE, HANDLE, DWORD, BOOL );
107 typedef unsigned (__stdcall *PTHREAD_START) (void *);
108
109 typedef struct
110 {
111     /* WinNT/2K/XP implementation */
112     HANDLE              mutex;
113     /* Win95/98/ME implementation */
114     CRITICAL_SECTION    csection;
115 } vlc_mutex_t;
116
117 typedef struct
118 {
119     volatile int        i_waiting_threads;
120     /* WinNT/2K/XP implementation */
121     HANDLE              event;
122     SIGNALOBJECTANDWAIT SignalObjectAndWait;
123     /* Win95/98/ME implementation */
124     HANDLE              semaphore;
125     CRITICAL_SECTION    csection;
126     int                 i_win9x_cv;
127 } vlc_cond_t;
128
129 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
130 typedef pthread_t        vlc_thread_t;
131 typedef pthread_mutex_t  vlc_mutex_t;
132 typedef pthread_cond_t   vlc_cond_t;
133
134 #elif defined( HAVE_CTHREADS_H )
135 typedef cthread_t        vlc_thread_t;
136
137 /* Those structs are the ones defined in /include/cthreads.h but we need
138  * to handle (&foo) where foo is a (mutex_t) while they handle (foo) where
139  * foo is a (mutex_t*) */
140 typedef struct
141 {
142     spin_lock_t held;
143     spin_lock_t lock;
144     char *name;
145     struct cthread_queue queue;
146 } vlc_mutex_t;
147
148 typedef struct
149 {
150     spin_lock_t lock;
151     struct cthread_queue queue;
152     char *name;
153     struct cond_imp *implications;
154 } vlc_cond_t;
155
156 #elif defined( HAVE_KERNEL_SCHEDULER_H )
157 /* This is the BeOS implementation of the vlc threads, note that the mutex is
158  * not a real mutex and the cond_var is not like a pthread cond_var but it is
159  * enough for what wee need */
160
161 typedef thread_id vlc_thread_t;
162
163 typedef struct
164 {
165     int32           init;
166     sem_id          lock;
167 } vlc_mutex_t;
168
169 typedef struct
170 {
171     int32           init;
172     thread_id       thread;
173 } vlc_cond_t;
174
175 #endif
176
177 /*****************************************************************************
178  * Function definitions
179  *****************************************************************************/
180 VLC_EXPORT( int,  __vlc_threads_init,  ( vlc_object_t * ) );
181 VLC_EXPORT( int,  __vlc_threads_end,   ( vlc_object_t * ) );
182 VLC_EXPORT( int,  __vlc_mutex_init,    ( vlc_object_t *, vlc_mutex_t * ) );
183 VLC_EXPORT( int,  __vlc_mutex_destroy, ( char *, int, vlc_mutex_t * ) );
184 VLC_EXPORT( int,  __vlc_cond_init,     ( vlc_object_t *, vlc_cond_t * ) );
185 VLC_EXPORT( int,  __vlc_cond_destroy,  ( char *, int, vlc_cond_t * ) );
186 VLC_EXPORT( int,  __vlc_thread_create, ( vlc_object_t *, char *, int, char *, void * ( * ) ( void * ), vlc_bool_t ) );
187 VLC_EXPORT( void, __vlc_thread_ready,  ( vlc_object_t * ) );
188 VLC_EXPORT( void, __vlc_thread_join,   ( vlc_object_t *, char *, int ) );
189
190 /*****************************************************************************
191  * vlc_threads_init: initialize threads system
192  *****************************************************************************/
193 #define vlc_threads_init( P_THIS )                                          \
194     __vlc_threads_init( CAST_TO_VLC_OBJECT(P_THIS) )
195
196 /*****************************************************************************
197  * vlc_threads_end: deinitialize threads system
198  *****************************************************************************/
199 #define vlc_threads_end( P_THIS )                                          \
200     __vlc_threads_end( CAST_TO_VLC_OBJECT(P_THIS) )
201
202 /*****************************************************************************
203  * vlc_mutex_init: initialize a mutex
204  *****************************************************************************/
205 #define vlc_mutex_init( P_THIS, P_MUTEX )                                   \
206     __vlc_mutex_init( CAST_TO_VLC_OBJECT(P_THIS), P_MUTEX )
207
208 /*****************************************************************************
209  * vlc_mutex_lock: lock a mutex
210  *****************************************************************************/
211 #ifdef DEBUG
212 #   define vlc_mutex_lock( P_MUTEX )                                        \
213         __vlc_mutex_lock( __FILE__, __LINE__, P_MUTEX )
214 #else
215 #   define vlc_mutex_lock( P_MUTEX )                                        \
216         __vlc_mutex_lock( "(unknown)", 0, P_MUTEX )
217 #endif
218
219 static inline int __vlc_mutex_lock( char * psz_file, int i_line,
220                                     vlc_mutex_t *p_mutex )
221 {
222 #if defined( PTH_INIT_IN_PTH_H )
223     return pth_mutex_acquire( p_mutex, TRUE, NULL );
224
225 #elif defined( ST_INIT_IN_ST_H )
226     return st_mutex_lock( *p_mutex );
227
228 #elif defined( WIN32 )
229     if( p_mutex->mutex )
230     {
231         WaitForSingleObject( p_mutex->mutex, INFINITE );
232     }
233     else
234     {
235         EnterCriticalSection( &p_mutex->csection );
236     }
237     return 0;
238
239 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
240     int i_return = pthread_mutex_lock( p_mutex );
241     if( i_return )
242     {
243 //        msg_Err( "thread %d: mutex_lock failed at %s:%d (%s)",
244 //                 pthread_self(), psz_file, i_line, strerror(i_return) );
245     }
246     return i_return;
247
248 #elif defined( HAVE_CTHREADS_H )
249     mutex_lock( p_mutex );
250     return 0;
251
252 #elif defined( HAVE_KERNEL_SCHEDULER_H )
253     status_t err;
254
255     if( !p_mutex )
256     {
257         return B_BAD_VALUE;
258     }
259
260     if( p_mutex->init < 2000 )
261     {
262         return B_NO_INIT;
263     }
264
265     err = acquire_sem( p_mutex->lock );
266     return err;
267
268 #endif
269 }
270
271 /*****************************************************************************
272  * vlc_mutex_unlock: unlock a mutex
273  *****************************************************************************/
274 #ifdef DEBUG
275 #   define vlc_mutex_unlock( P_MUTEX )                                      \
276         __vlc_mutex_unlock( __FILE__, __LINE__, P_MUTEX )
277 #else
278 #   define vlc_mutex_unlock( P_MUTEX )                                      \
279         __vlc_mutex_unlock( "(unknown)", 0, P_MUTEX )
280 #endif
281
282 static inline int __vlc_mutex_unlock( char * psz_file, int i_line,
283                                       vlc_mutex_t *p_mutex )
284 {
285 #if defined( PTH_INIT_IN_PTH_H )
286     return pth_mutex_release( p_mutex );
287
288 #elif defined( ST_INIT_IN_ST_H )
289     return st_mutex_unlock( *p_mutex );
290
291 #elif defined( WIN32 )
292     if( p_mutex->mutex )
293     {
294         ReleaseMutex( p_mutex->mutex );
295     }
296     else
297     {
298         LeaveCriticalSection( &p_mutex->csection );
299     }
300     return 0;
301
302 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
303     int i_return = pthread_mutex_unlock( p_mutex );
304     if( i_return )
305     {
306 //        msg_Err( "thread %d: mutex_unlock failed at %s:%d (%s)",
307 //                 pthread_self(), psz_file, i_line, strerror(i_return) );
308     }
309     return i_return;
310
311 #elif defined( HAVE_CTHREADS_H )
312     mutex_unlock( p_mutex );
313     return 0;
314
315 #elif defined( HAVE_KERNEL_SCHEDULER_H )
316     if( !p_mutex)
317     {
318         return B_BAD_VALUE;
319     }
320
321     if( p_mutex->init < 2000 )
322     {
323         return B_NO_INIT;
324     }
325
326     release_sem( p_mutex->lock );
327     return B_OK;
328
329 #endif
330 }
331
332 /*****************************************************************************
333  * vlc_mutex_destroy: destroy a mutex
334  *****************************************************************************/
335 #ifdef DEBUG
336 #   define vlc_mutex_destroy( P_MUTEX )                                     \
337         __vlc_mutex_destroy( __FILE__, __LINE__, P_MUTEX )
338 #else
339 #   define vlc_mutex_destroy( P_MUTEX )                                     \
340         __vlc_mutex_destroy( "(unknown)", 0, P_MUTEX )
341 #endif
342
343 /*****************************************************************************
344  * vlc_cond_init: initialize a condition
345  *****************************************************************************/
346 #define vlc_cond_init( P_THIS, P_COND )                                   \
347     __vlc_cond_init( CAST_TO_VLC_OBJECT(P_THIS), P_COND )
348
349 /*****************************************************************************
350  * vlc_cond_signal: start a thread on condition completion
351  *****************************************************************************/
352 static inline int vlc_cond_signal( vlc_cond_t *p_condvar )
353 {
354 #if defined( PTH_INIT_IN_PTH_H )
355     return pth_cond_notify( p_condvar, FALSE );
356
357 #elif defined( ST_INIT_IN_ST_H )
358     return st_cond_signal( *p_condvar );
359
360 #elif defined( WIN32 )
361     /* Release one waiting thread if one is available. */
362     /* For this trick to work properly, the vlc_cond_signal must be surrounded
363      * by a mutex. This will prevent another thread from stealing the signal */
364     if( !p_condvar->semaphore )
365     {
366         PulseEvent( p_condvar->event );
367     }
368     else if( p_condvar->i_win9x_cv == 1 )
369     {
370         /* Wait for the gate to be open */
371         WaitForSingleObject( p_condvar->event, INFINITE );
372
373         if( p_condvar->i_waiting_threads )
374         {
375             /* Using a semaphore exposes us to a race condition. It is
376              * possible for another thread to start waiting on the semaphore
377              * just after we signaled it and thus steal the signal.
378              * We have to prevent new threads from entering the cond_wait(). */
379             ResetEvent( p_condvar->event );
380
381             /* A semaphore is used here because Win9x doesn't have
382              * SignalObjectAndWait() and thus a race condition exists
383              * during the time we release the mutex and the time we start
384              * waiting on the event (more precisely, the signal can sometimes
385              * be missed by the waiting thread if we use PulseEvent()). */
386             ReleaseSemaphore( p_condvar->semaphore, 1, 0 );
387         }
388     }
389     else
390     {
391         if( p_condvar->i_waiting_threads )
392         {
393             ReleaseSemaphore( p_condvar->semaphore, 1, 0 );
394
395             /* Wait for the last thread to be awakened */
396             WaitForSingleObject( p_condvar->event, INFINITE );
397         }
398     }
399     return 0;
400
401 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
402     return pthread_cond_signal( p_condvar );
403
404 #elif defined( HAVE_CTHREADS_H )
405     /* condition_signal() */
406     if ( p_condvar->queue.head || p_condvar->implications )
407     {
408         cond_signal( (condition_t)p_condvar );
409     }
410     return 0;
411
412 #elif defined( HAVE_KERNEL_SCHEDULER_H )
413     if( !p_condvar )
414     {
415         return B_BAD_VALUE;
416     }
417
418     if( p_condvar->init < 2000 )
419     {
420         return B_NO_INIT;
421     }
422
423     while( p_condvar->thread != -1 )
424     {
425         thread_info info;
426         if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE )
427         {
428             return 0;
429         }
430
431         if( info.state != B_THREAD_SUSPENDED )
432         {
433             /* The  waiting thread is not suspended so it could
434              * have been interrupted beetwen the unlock and the
435              * suspend_thread line. That is why we sleep a little
436              * before retesting p_condver->thread. */
437             snooze( 10000 );
438         }
439         else
440         {
441             /* Ok, we have to wake up that thread */
442             resume_thread( p_condvar->thread );
443             return 0;
444         }
445     }
446     return 0;
447
448 #endif
449 }
450
451 /*****************************************************************************
452  * vlc_cond_broadcast: start all threads waiting on condition completion
453  *****************************************************************************/
454 /*
455  * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
456  * Only works with pthreads, you need to adapt it for others
457  * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
458  */
459 static inline int vlc_cond_broadcast( vlc_cond_t *p_condvar )
460 {
461 #if defined( PTH_INIT_IN_PTH_H )
462     return pth_cond_notify( p_condvar, FALSE );
463
464 #elif defined( ST_INIT_IN_ST_H )
465     return st_cond_broadcast( p_condvar );
466
467 #elif defined( WIN32 )
468     /* Release all waiting threads. */
469     int i;
470
471     if( !p_condvar->semaphore )
472         for( i = p_condvar->i_waiting_threads; i > 0; i-- )
473             PulseEvent( p_condvar->event );
474     else if( p_condvar->i_win9x_cv == 1 )
475     {
476         /* Wait for the gate to be open */
477         WaitForSingleObject( p_condvar->event, INFINITE );
478
479         if( p_condvar->i_waiting_threads )
480         {
481             /* close gate */
482             ResetEvent( p_condvar->event );
483
484             ReleaseSemaphore( p_condvar->semaphore,
485                               p_condvar->i_waiting_threads, 0 );
486         }
487     }
488     else
489     {
490         if( p_condvar->i_waiting_threads )
491         {
492             ReleaseSemaphore( p_condvar->semaphore,
493                               p_condvar->i_waiting_threads, 0 );
494             /* Wait for the last thread to be awakened */
495             WaitForSingleObject( p_condvar->event, INFINITE );
496         }
497     }
498
499     return 0;
500
501 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
502     return pthread_cond_broadcast( p_condvar );
503
504 #elif defined( HAVE_CTHREADS_H )
505     /* condition_signal() */
506     if ( p_condvar->queue.head || p_condvar->implications )
507     {
508         cond_signal( (condition_t)p_condvar );
509     }
510     return 0;
511
512 #elif defined( HAVE_KERNEL_SCHEDULER_H )
513     if( !p_condvar )
514     {
515         return B_BAD_VALUE;
516     }
517
518     if( p_condvar->init < 2000 )
519     {
520         return B_NO_INIT;
521     }
522
523     while( p_condvar->thread != -1 )
524     {
525         thread_info info;
526         if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE )
527         {
528             return 0;
529         }
530
531         if( info.state != B_THREAD_SUSPENDED )
532         {
533             /* The  waiting thread is not suspended so it could
534              * have been interrupted beetwen the unlock and the
535              * suspend_thread line. That is why we sleep a little
536              * before retesting p_condver->thread. */
537             snooze( 10000 );
538         }
539         else
540         {
541             /* Ok, we have to wake up that thread */
542             resume_thread( p_condvar->thread );
543             return 0;
544         }
545     }
546     return 0;
547
548 #endif
549 }
550
551 /*****************************************************************************
552  * vlc_cond_wait: wait until condition completion
553  *****************************************************************************/
554 #ifdef DEBUG
555 #   define vlc_cond_wait( P_COND, P_MUTEX )                                   \
556         __vlc_cond_wait( __FILE__, __LINE__, P_COND, P_MUTEX  )
557 #else
558 #   define vlc_cond_wait( P_COND, P_MUTEX )                                   \
559         __vlc_cond_wait( "(unknown)", 0, P_COND, P_MUTEX )
560 #endif
561
562 static inline int __vlc_cond_wait( char * psz_file, int i_line,
563                                    vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex )
564 {
565 #if defined( PTH_INIT_IN_PTH_H )
566     return pth_cond_await( p_condvar, p_mutex, NULL );
567
568 #elif defined( ST_INIT_IN_ST_H )
569     int i_ret;
570
571     st_mutex_unlock( *p_mutex );
572     i_ret = st_cond_wait( *p_condvar );
573     st_mutex_lock( *p_mutex );
574
575     return i_ret;
576
577 #elif defined( WIN32 )
578     if( !p_condvar->semaphore )
579     {
580         /* Increase our wait count */
581         p_condvar->i_waiting_threads++;
582
583         if( p_condvar->SignalObjectAndWait )
584         /* It is only possible to atomically release the mutex and initiate the
585          * waiting on WinNT/2K/XP. Win9x doesn't have SignalObjectAndWait(). */
586             p_condvar->SignalObjectAndWait( p_mutex->mutex,
587                                             p_condvar->event,
588                                             INFINITE, FALSE );
589         else
590         {
591             LeaveCriticalSection( &p_mutex->csection );
592             WaitForSingleObject( p_condvar->event, INFINITE );
593         }
594     }
595     else if( p_condvar->i_win9x_cv == 1 )
596     {
597         int i_waiting_threads;
598
599         /* Wait for the gate to be open */
600         WaitForSingleObject( p_condvar->event, INFINITE );
601
602         /* Increase our wait count */
603         p_condvar->i_waiting_threads++;
604
605         LeaveCriticalSection( &p_mutex->csection );
606         WaitForSingleObject( p_condvar->semaphore, INFINITE );
607
608         /* Decrement and test must be atomic */
609         EnterCriticalSection( &p_condvar->csection );
610
611         /* Decrease our wait count */
612         i_waiting_threads = --p_condvar->i_waiting_threads;
613
614         LeaveCriticalSection( &p_condvar->csection );
615
616         /* Reopen the gate if we were the last waiting thread */
617         if( !i_waiting_threads )
618             SetEvent( p_condvar->event );
619     }
620     else
621     {
622         int i_waiting_threads;
623
624         /* Increase our wait count */
625         p_condvar->i_waiting_threads++;
626
627         LeaveCriticalSection( &p_mutex->csection );
628         WaitForSingleObject( p_condvar->semaphore, INFINITE );
629
630         /* Decrement and test must be atomic */
631         EnterCriticalSection( &p_condvar->csection );
632
633         /* Decrease our wait count */
634         i_waiting_threads = --p_condvar->i_waiting_threads;
635
636         LeaveCriticalSection( &p_condvar->csection );
637
638         /* Signal that the last waiting thread just went through */
639         if( !i_waiting_threads )
640             SetEvent( p_condvar->event );
641     }
642
643     /* Reacquire the mutex before returning. */
644     vlc_mutex_lock( p_mutex );
645
646     return 0;
647
648 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
649
650 #   ifdef DEBUG
651     /* In debug mode, timeout */
652     struct timeval now;
653     struct timespec timeout;
654     int    i_result;
655
656     for( ; ; )
657     {
658         gettimeofday( &now, NULL );
659         timeout.tv_sec = now.tv_sec + THREAD_COND_TIMEOUT;
660         timeout.tv_nsec = now.tv_usec * 1000;
661
662         i_result = pthread_cond_timedwait( p_condvar, p_mutex, &timeout );
663
664         if( i_result == ETIMEDOUT )
665         {
666 //X            msg_Warn( "thread %d: possible deadlock detected "
667 //X                      "in cond_wait at %s:%d (%s)", pthread_self(),
668 //X                      psz_file, i_line, strerror(i_result) );
669             continue;
670         }
671
672         if( i_result )
673         {
674 //X            msg_Err( "thread %d: cond_wait failed at %s:%d (%s)",
675 //X                     pthread_self(), psz_file, i_line, strerror(i_result) );
676         }
677         return( i_result );
678     }
679 #   else
680     return pthread_cond_wait( p_condvar, p_mutex );
681 #   endif
682
683 #elif defined( HAVE_CTHREADS_H )
684     condition_wait( (condition_t)p_condvar, (mutex_t)p_mutex );
685     return 0;
686
687 #elif defined( HAVE_KERNEL_SCHEDULER_H )
688     if( !p_condvar )
689     {
690         return B_BAD_VALUE;
691     }
692
693     if( !p_mutex )
694     {
695         return B_BAD_VALUE;
696     }
697
698     if( p_condvar->init < 2000 )
699     {
700         return B_NO_INIT;
701     }
702
703     /* The p_condvar->thread var is initialized before the unlock because
704      * it enables to identify when the thread is interrupted beetwen the
705      * unlock line and the suspend_thread line */
706     p_condvar->thread = find_thread( NULL );
707     vlc_mutex_unlock( p_mutex );
708     suspend_thread( p_condvar->thread );
709     p_condvar->thread = -1;
710
711     vlc_mutex_lock( p_mutex );
712     return 0;
713
714 #endif
715 }
716
717 /*****************************************************************************
718  * vlc_cond_destroy: destroy a condition
719  *****************************************************************************/
720 #ifdef DEBUG
721 #   define vlc_cond_destroy( P_COND )                                       \
722         __vlc_cond_destroy( __FILE__, __LINE__, P_COND )
723 #else
724 #   define vlc_cond_destroy( P_COND )                                       \
725         __vlc_cond_destroy( "(unknown)", 0, P_COND )
726 #endif
727
728 /*****************************************************************************
729  * vlc_thread_create: create a thread
730  *****************************************************************************/
731 #   define vlc_thread_create( P_THIS, PSZ_NAME, FUNC, WAIT )                \
732         __vlc_thread_create( CAST_TO_VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, (void * ( * ) ( void * ))FUNC, WAIT )
733
734 /*****************************************************************************
735  * vlc_thread_ready: tell the parent thread we were successfully spawned
736  *****************************************************************************/
737 #   define vlc_thread_ready( P_THIS )                                       \
738         __vlc_thread_ready( CAST_TO_VLC_OBJECT(P_THIS) )
739
740 /*****************************************************************************
741  * vlc_thread_join: wait until a thread exits
742  *****************************************************************************/
743 #ifdef DEBUG
744 #   define vlc_thread_join( P_THIS )                                        \
745         __vlc_thread_join( CAST_TO_VLC_OBJECT(P_THIS), __FILE__, __LINE__ ) 
746 #else
747 #   define vlc_thread_join( P_THIS )                                        \
748         __vlc_thread_join( CAST_TO_VLC_OBJECT(P_THIS), "(unknown)", 0 ) 
749 #endif