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
7 * Authors: Jean-Marc Dressler <polux@via.ecp.fr>
8 * Samuel Hocevar <sam@via.ecp.fr>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 02111-1307, USA.
24 *****************************************************************************/
26 #if defined(HAVE_PTHREAD_H) /* pthreads (Linux & BSD for example) */
29 #elif defined(HAVE_CTHREADS_H) /* GNUMach */
32 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H) /* BeOS */
33 #include <kernel/OS.h>
34 #include <kernel/scheduler.h>
37 #error no threads available on your system !
40 /*****************************************************************************
42 *****************************************************************************
43 * These constants are used by all threads in *_CreateThread() and
44 * *_DestroyThreads() functions. Since those calls are non-blocking, an integer
45 * value is used as a shared flag to represent the status of the thread.
46 *****************************************************************************/
48 /* Void status - this value can be used to make sure no operation is currently
49 * in progress on the concerned thread in an array of recorded threads */
50 #define THREAD_NOP 0 /* nothing happened */
53 #define THREAD_CREATE 10 /* thread is initializing */
54 #define THREAD_START 11 /* thread has forked */
55 #define THREAD_READY 19 /* thread is ready */
57 /* Destructions status */
58 #define THREAD_DESTROY 20 /* destruction order has been sent */
59 #define THREAD_END 21 /* destruction order has been received */
60 #define THREAD_OVER 29 /* thread does not exist any more */
63 #define THREAD_ERROR 30 /* an error occured */
64 #define THREAD_FATAL 31 /* an fatal error occured - program must end */
66 /*****************************************************************************
68 *****************************************************************************/
70 #if defined(HAVE_CTHREADS_H)
72 typedef cthread_t vlc_thread_t;
74 /* those structs are the ones defined in /include/cthreads.h but we need
75 * to handle (*foo) where foo is a (mutex_t) while they handle (foo) where
76 * foo is a (mutex_t*) */
77 typedef struct s_mutex {
81 struct cthread_queue queue;
84 typedef struct s_condition {
86 struct cthread_queue queue;
88 struct cond_imp *implications;
91 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
93 typedef thread_id vlc_thread_t;
112 #elif defined(HAVE_PTHREAD_H)
114 typedef pthread_t vlc_thread_t;
115 typedef pthread_mutex_t vlc_mutex_t;
116 typedef pthread_cond_t vlc_cond_t;
120 typedef void *(*vlc_thread_func_t)(void *p_data);
122 /*****************************************************************************
124 *****************************************************************************/
126 static __inline__ int vlc_thread_create( vlc_thread_t *p_thread, char *psz_name,
127 vlc_thread_func_t func, void *p_data );
128 static __inline__ void vlc_thread_exit ( void );
129 static __inline__ void vlc_thread_join ( vlc_thread_t thread );
131 static __inline__ int vlc_mutex_init ( vlc_mutex_t *p_mutex );
132 static __inline__ int vlc_mutex_lock ( vlc_mutex_t *p_mutex );
133 static __inline__ int vlc_mutex_unlock ( vlc_mutex_t *p_mutex );
135 static __inline__ int vlc_cond_init ( vlc_cond_t *p_condvar );
136 static __inline__ int vlc_cond_signal ( vlc_cond_t *p_condvar );
137 static __inline__ int vlc_cond_wait ( vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex );
140 static _inline__ int vlc_cond_timedwait ( vlc_cond_t * condvar, vlc_mutex_t * mutex,
141 mtime_t absoute_timeout_time );
144 /*****************************************************************************
145 * vlc_thread_create: create a thread
146 *****************************************************************************/
147 static __inline__ int vlc_thread_create( vlc_thread_t *p_thread,
148 char *psz_name, vlc_thread_func_t func,
151 #if defined(HAVE_CTHREADS_H)
152 *p_thread = cthread_fork( (cthread_fn_t)func, (any_t)p_data );
155 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
156 *p_thread = spawn_thread( (thread_func)func, psz_name,
157 B_NORMAL_PRIORITY, p_data );
158 return resume_thread( *p_thread );
160 #elif defined(HAVE_PTHREAD_H)
161 return pthread_create( p_thread, NULL, func, p_data );
166 /*****************************************************************************
167 * vlc_thread_exit: terminate a thread
168 *****************************************************************************/
169 static __inline__ void vlc_thread_exit( void )
171 #if defined(HAVE_CTHREADS_H)
173 cthread_exit( &result );
175 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
178 #elif defined(HAVE_PTHREAD_H)
184 /*****************************************************************************
185 * vlc_thread_join: wait until a thread exits
186 *****************************************************************************/
187 static __inline__ void vlc_thread_join( vlc_thread_t thread )
189 #if defined(HAVE_CTHREADS_H)
190 cthread_join( thread );
192 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
194 wait_for_thread( thread, &exit_value );
196 #elif defined(HAVE_PTHREAD_H)
197 pthread_join( thread, NULL );
202 #if defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
203 /* lazy_init_mutex */
204 static __inline__ void lazy_init_mutex(vlc_mutex_t* p_mutex)
206 int32 v = atomic_or( &p_mutex->init, 1 );
207 if( 2000 == v ) /* we're the first, so do the init */
209 vlc_mutex_init( p_mutex );
211 else /* we're not the first, so wait until the init is finished */
213 while( p_mutex->init != 9999 )
221 /*****************************************************************************
222 * vlc_mutex_init: initialize a mutex
223 *****************************************************************************/
224 static __inline__ int vlc_mutex_init( vlc_mutex_t *p_mutex )
226 #if defined(HAVE_CTHREADS_H)
227 mutex_init( p_mutex );
230 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
231 // check the arguments and whether it's already been initialized
235 if( p_mutex->init == 9999 )
238 p_mutex->lock = create_sem( 1, "BeMutex" );
240 p_mutex->init = 9999;
243 #elif defined(HAVE_PTHREAD_H)
244 return pthread_mutex_init( p_mutex, NULL );
249 /*****************************************************************************
250 * vlc_mutex_lock: lock a mutex
251 *****************************************************************************/
252 static __inline__ int vlc_mutex_lock( vlc_mutex_t *p_mutex )
254 #if defined(HAVE_CTHREADS_H)
255 mutex_lock( p_mutex );
258 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
264 if( p_mutex->init < 2000 )
267 lazy_init_mutex( p_mutex );
269 err = acquire_sem( p_mutex->lock );
271 p_mutex->owner = find_thread( NULL );
275 #elif defined(HAVE_PTHREAD_H)
276 return pthread_mutex_lock( p_mutex );
281 /*****************************************************************************
282 * vlc_mutex_unlock: unlock a mutex
283 *****************************************************************************/
284 static __inline__ int vlc_mutex_unlock( vlc_mutex_t *p_mutex )
286 #if defined(HAVE_CTHREADS_H)
287 mutex_unlock( p_mutex );
290 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
294 if( p_mutex->init < 2000 )
297 lazy_init_mutex( p_mutex );
299 if( p_mutex->owner != find_thread(NULL) )
303 release_sem( p_mutex->lock );
306 #elif defined(HAVE_PTHREAD_H)
307 return pthread_mutex_unlock( p_mutex );
312 #if defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
314 static __inline__ void lazy_init_cond( vlc_cond_t* p_condvar )
316 int32 v = atomic_or( &p_condvar->init, 1 );
317 if( 2000 == v ) /* we're the first, so do the init */
319 vlc_cond_init( p_condvar );
321 else /* we're not the first, so wait until the init is finished */
323 while( p_condvar->init != 9999 )
331 /*****************************************************************************
332 * vlc_cond_init: initialize a condition
333 *****************************************************************************/
334 static __inline__ int vlc_cond_init( vlc_cond_t *p_condvar )
336 #if defined(HAVE_CTHREADS_H)
337 /* condition_init() */
338 spin_lock_init( &p_condvar->lock );
339 cthread_queue_init( &p_condvar->queue );
341 p_condvar->implications = 0;
345 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
349 if( p_condvar->init == 9999 )
352 p_condvar->sem = create_sem( 0, "CVSem" );
353 p_condvar->handshakeSem = create_sem( 0, "CVHandshake" );
354 p_condvar->signalSem = create_sem( 1, "CVSignal" );
355 p_condvar->ns = p_condvar->nw = 0;
356 p_condvar->init = 9999;
359 #elif defined(HAVE_PTHREAD_H)
360 return pthread_cond_init( p_condvar, NULL );
365 /*****************************************************************************
366 * vlc_cond_signal: start a thread on condition completion
367 *****************************************************************************/
368 static __inline__ int vlc_cond_signal( vlc_cond_t *p_condvar )
370 #if defined(HAVE_CTHREADS_H)
371 /* condition_signal() */
372 if ( p_condvar->queue.head || p_condvar->implications )
374 cond_signal( (condition_t)p_condvar );
378 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
384 if( p_condvar->init < 2000 )
387 lazy_init_cond( p_condvar );
389 if( acquire_sem(p_condvar->signalSem) == B_INTERRUPTED)
390 return B_INTERRUPTED;
392 if( p_condvar->nw > p_condvar->ns )
395 release_sem( p_condvar->sem );
396 release_sem( p_condvar->signalSem );
398 while( acquire_sem(p_condvar->handshakeSem) == B_INTERRUPTED )
405 release_sem( p_condvar->signalSem );
409 #elif defined(HAVE_PTHREAD_H)
410 return pthread_cond_signal( p_condvar );
415 /*****************************************************************************
416 * vlc_cond_wait: wait until condition completion
417 *****************************************************************************/
418 static __inline__ int vlc_cond_wait( vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex )
420 #if defined(HAVE_CTHREADS_H)
421 condition_wait( (condition_t)p_condvar, (mutex_t)p_mutex );
424 #elif defined(HAVE_KERNEL_SCHEDULER_H) && defined(HAVE_KERNEL_OS_H)
433 if( p_condvar->init < 2000 )
436 lazy_init_cond( p_condvar );
438 if( acquire_sem(p_condvar->signalSem) == B_INTERRUPTED )
439 return B_INTERRUPTED;
442 release_sem( p_condvar->signalSem );
444 vlc_mutex_unlock( p_mutex );
445 err = acquire_sem( p_condvar->sem );
447 while( acquire_sem(p_condvar->signalSem) == B_INTERRUPTED)
452 if( p_condvar->ns > 0 )
454 release_sem( p_condvar->handshakeSem );
458 release_sem( p_condvar->signalSem );
460 while( vlc_mutex_lock(p_mutex) == B_INTERRUPTED)
466 #elif defined(HAVE_PTHREAD_H)
467 return pthread_cond_wait( p_condvar, p_mutex );