1 /*****************************************************************************
2 * vlc_threads.h : threads implementation for the VideoLAN client
3 * This header provides portable declarations for mutexes & conditions
4 *****************************************************************************
5 * Copyright (C) 1999, 2002 the VideoLAN team
8 * Authors: Jean-Marc Dressler <polux@via.ecp.fr>
9 * Samuel Hocevar <sam@via.ecp.fr>
10 * Gildas Bazin <gbazin@netcourrier.com>
11 * Christophe Massiot <massiot@via.ecp.fr>
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
26 *****************************************************************************/
28 #ifndef VLC_THREADS_H_
29 #define VLC_THREADS_H_
33 * This file defines structures and functions for handling threads in vlc
37 #if defined( UNDER_CE )
39 #elif defined( WIN32 )
40 # include <process.h> /* Win32 API */
43 #elif defined( SYS_BEOS ) /* BeOS */
44 # include <kernel/OS.h>
45 # include <kernel/scheduler.h>
46 # include <byteorder.h>
48 #else /* pthreads (like Linux & BSD) */
49 # define LIBVLC_USE_PTHREAD 1
50 # define _APPLE_C_SOURCE 1 /* Proper pthread semantics on OSX */
52 # include <stdlib.h> /* lldiv_t definition (only in C99) */
53 # include <unistd.h> /* _POSIX_SPIN_LOCKS */
55 /* Needed for pthread_cond_timedwait */
61 /*****************************************************************************
63 *****************************************************************************/
65 /* Thread priorities */
67 # define VLC_THREAD_PRIORITY_LOW 0
68 # define VLC_THREAD_PRIORITY_INPUT 22
69 # define VLC_THREAD_PRIORITY_AUDIO 22
70 # define VLC_THREAD_PRIORITY_VIDEO 0
71 # define VLC_THREAD_PRIORITY_OUTPUT 22
72 # define VLC_THREAD_PRIORITY_HIGHEST 22
74 #elif defined(SYS_BEOS)
75 # define VLC_THREAD_PRIORITY_LOW 5
76 # define VLC_THREAD_PRIORITY_INPUT 10
77 # define VLC_THREAD_PRIORITY_AUDIO 10
78 # define VLC_THREAD_PRIORITY_VIDEO 5
79 # define VLC_THREAD_PRIORITY_OUTPUT 15
80 # define VLC_THREAD_PRIORITY_HIGHEST 15
82 #elif defined(LIBVLC_USE_PTHREAD)
83 # define VLC_THREAD_PRIORITY_LOW 0
84 # define VLC_THREAD_PRIORITY_INPUT 10
85 # define VLC_THREAD_PRIORITY_AUDIO 5
86 # define VLC_THREAD_PRIORITY_VIDEO 0
87 # define VLC_THREAD_PRIORITY_OUTPUT 15
88 # define VLC_THREAD_PRIORITY_HIGHEST 20
90 #elif defined(WIN32) || defined(UNDER_CE)
91 /* Define different priorities for WinNT/2K/XP and Win9x/Me */
92 # define VLC_THREAD_PRIORITY_LOW 0
93 # define VLC_THREAD_PRIORITY_INPUT \
94 (IS_WINNT ? THREAD_PRIORITY_ABOVE_NORMAL : 0)
95 # define VLC_THREAD_PRIORITY_AUDIO \
96 (IS_WINNT ? THREAD_PRIORITY_HIGHEST : 0)
97 # define VLC_THREAD_PRIORITY_VIDEO \
98 (IS_WINNT ? 0 : THREAD_PRIORITY_BELOW_NORMAL )
99 # define VLC_THREAD_PRIORITY_OUTPUT \
100 (IS_WINNT ? THREAD_PRIORITY_ABOVE_NORMAL : 0)
101 # define VLC_THREAD_PRIORITY_HIGHEST \
102 (IS_WINNT ? THREAD_PRIORITY_TIME_CRITICAL : 0)
105 # define VLC_THREAD_PRIORITY_LOW 0
106 # define VLC_THREAD_PRIORITY_INPUT 0
107 # define VLC_THREAD_PRIORITY_AUDIO 0
108 # define VLC_THREAD_PRIORITY_VIDEO 0
109 # define VLC_THREAD_PRIORITY_OUTPUT 0
110 # define VLC_THREAD_PRIORITY_HIGHEST 0
114 /*****************************************************************************
116 *****************************************************************************/
118 #if defined (LIBVLC_USE_PTHREAD)
119 typedef pthread_t vlc_thread_t;
120 typedef pthread_mutex_t vlc_mutex_t;
121 typedef pthread_cond_t vlc_cond_t;
122 typedef pthread_key_t vlc_threadvar_t;
124 #elif defined( WIN32 ) || defined( UNDER_CE )
125 typedef HANDLE vlc_thread_t;
126 typedef HANDLE vlc_mutex_t;
127 typedef HANDLE vlc_cond_t;
128 typedef DWORD vlc_threadvar_t;
130 #elif defined( SYS_BEOS )
131 /* This is the BeOS implementation of the vlc threads, note that the mutex is
132 * not a real mutex and the cond_var is not like a pthread cond_var but it is
133 * enough for what we need */
135 typedef thread_id vlc_thread_t;
155 #if defined( WIN32 ) && !defined ETIMEDOUT
156 # define ETIMEDOUT 10060 /* This is the value in winsock.h. */
159 /*****************************************************************************
160 * Function definitions
161 *****************************************************************************/
162 VLC_EXPORT( int, vlc_mutex_init, ( vlc_mutex_t * ) );
163 VLC_EXPORT( int, vlc_mutex_init_recursive, ( vlc_mutex_t * ) );
164 VLC_EXPORT( void, __vlc_mutex_destroy, ( const char *, int, vlc_mutex_t * ) );
165 VLC_EXPORT( int, __vlc_cond_init, ( vlc_cond_t * ) );
166 VLC_EXPORT( void, __vlc_cond_destroy, ( const char *, int, vlc_cond_t * ) );
167 VLC_EXPORT( int, vlc_threadvar_create, (vlc_threadvar_t * , void (*) (void *) ) );
168 VLC_EXPORT( void, vlc_threadvar_delete, (vlc_threadvar_t *) );
169 VLC_EXPORT( int, __vlc_thread_create, ( vlc_object_t *, const char *, int, const char *, void * ( * ) ( vlc_object_t * ), int, bool ) );
170 VLC_EXPORT( int, __vlc_thread_set_priority, ( vlc_object_t *, const char *, int, int ) );
171 VLC_EXPORT( void, __vlc_thread_join, ( vlc_object_t *, const char *, int ) );
173 #define vlc_thread_ready vlc_object_signal
175 /*****************************************************************************
176 * vlc_mutex_lock: lock a mutex
177 *****************************************************************************/
178 #define vlc_mutex_lock( P_MUTEX ) \
179 __vlc_mutex_lock( __FILE__, __LINE__, P_MUTEX )
181 VLC_EXPORT(void, vlc_pthread_fatal, (const char *action, int error, const char *file, unsigned line));
183 #if defined(LIBVLC_USE_PTHREAD)
184 # define VLC_THREAD_ASSERT( action ) \
186 vlc_pthread_fatal (action, val, psz_file, i_line)
188 # define VLC_THREAD_ASSERT ((void)(val))
191 static inline void __vlc_mutex_lock( const char * psz_file, int i_line,
192 vlc_mutex_t * p_mutex )
194 #if defined(LIBVLC_USE_PTHREAD)
195 # define vlc_assert_locked( m ) \
196 assert (pthread_mutex_lock (m) == EDEADLK)
197 int val = pthread_mutex_lock( p_mutex );
198 VLC_THREAD_ASSERT ("locking mutex");
200 #elif defined( UNDER_CE )
201 (void)psz_file; (void)i_line;
203 EnterCriticalSection( &p_mutex->csection );
205 #elif defined( WIN32 )
206 (void)psz_file; (void)i_line;
208 WaitForSingleObject( *p_mutex, INFINITE );
210 #elif defined( SYS_BEOS )
211 acquire_sem( p_mutex->lock );
216 #ifndef vlc_assert_locked
217 # define vlc_assert_locked( m ) (void)m
220 /*****************************************************************************
221 * vlc_mutex_unlock: unlock a mutex
222 *****************************************************************************/
223 #define vlc_mutex_unlock( P_MUTEX ) \
224 __vlc_mutex_unlock( __FILE__, __LINE__, P_MUTEX )
226 static inline void __vlc_mutex_unlock( const char * psz_file, int i_line,
227 vlc_mutex_t *p_mutex )
229 #if defined(LIBVLC_USE_PTHREAD)
230 int val = pthread_mutex_unlock( p_mutex );
231 VLC_THREAD_ASSERT ("unlocking mutex");
233 #elif defined( UNDER_CE )
234 (void)psz_file; (void)i_line;
236 LeaveCriticalSection( &p_mutex->csection );
238 #elif defined( WIN32 )
239 (void)psz_file; (void)i_line;
241 ReleaseMutex( *p_mutex );
243 #elif defined( SYS_BEOS )
244 release_sem( p_mutex->lock );
249 /*****************************************************************************
250 * vlc_mutex_destroy: destroy a mutex
251 *****************************************************************************/
252 #define vlc_mutex_destroy( P_MUTEX ) \
253 __vlc_mutex_destroy( __FILE__, __LINE__, P_MUTEX )
255 /*****************************************************************************
256 * vlc_cond_init: initialize a condition
257 *****************************************************************************/
258 #define vlc_cond_init( P_THIS, P_COND ) \
259 __vlc_cond_init( P_COND )
261 /*****************************************************************************
262 * vlc_cond_signal: start a thread on condition completion
263 *****************************************************************************/
264 #define vlc_cond_signal( P_COND ) \
265 __vlc_cond_signal( __FILE__, __LINE__, P_COND )
267 static inline void __vlc_cond_signal( const char * psz_file, int i_line,
268 vlc_cond_t *p_condvar )
270 #if defined(LIBVLC_USE_PTHREAD)
271 int val = pthread_cond_signal( p_condvar );
272 VLC_THREAD_ASSERT ("signaling condition variable");
274 #elif defined( UNDER_CE ) || defined( WIN32 )
275 (void)psz_file; (void)i_line;
277 /* Release one waiting thread if one is available. */
278 /* For this trick to work properly, the vlc_cond_signal must be surrounded
279 * by a mutex. This will prevent another thread from stealing the signal */
280 /* PulseEvent() only works if none of the waiting threads is suspended.
281 * This is particularily problematic under a debug session.
282 * as documented in http://support.microsoft.com/kb/q173260/ */
283 PulseEvent( *p_condvar );
285 #elif defined( SYS_BEOS )
286 while( p_condvar->thread != -1 )
289 if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE )
292 if( info.state != B_THREAD_SUSPENDED )
294 /* The waiting thread is not suspended so it could
295 * have been interrupted beetwen the unlock and the
296 * suspend_thread line. That is why we sleep a little
297 * before retesting p_condver->thread. */
302 /* Ok, we have to wake up that thread */
303 resume_thread( p_condvar->thread );
310 /*****************************************************************************
311 * vlc_cond_wait: wait until condition completion
312 *****************************************************************************/
313 #define vlc_cond_wait( P_COND, P_MUTEX ) \
314 __vlc_cond_wait( __FILE__, __LINE__, P_COND, P_MUTEX )
316 static inline void __vlc_cond_wait( const char * psz_file, int i_line,
317 vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex )
319 #if defined(LIBVLC_USE_PTHREAD)
320 int val = pthread_cond_wait( p_condvar, p_mutex );
321 VLC_THREAD_ASSERT ("waiting on condition");
323 #elif defined( UNDER_CE )
324 LeaveCriticalSection( &p_mutex->csection );
325 WaitForSingleObject( *p_condvar, INFINITE );
327 /* Reacquire the mutex before returning. */
328 vlc_mutex_lock( p_mutex );
330 #elif defined( WIN32 )
331 (void)psz_file; (void)i_line;
333 /* Increase our wait count */
334 SignalObjectAndWait( *p_mutex, *p_condvar, INFINITE, FALSE );
336 /* Reacquire the mutex before returning. */
337 vlc_mutex_lock( p_mutex );
339 #elif defined( SYS_BEOS )
340 /* The p_condvar->thread var is initialized before the unlock because
341 * it enables to identify when the thread is interrupted beetwen the
342 * unlock line and the suspend_thread line */
343 p_condvar->thread = find_thread( NULL );
344 vlc_mutex_unlock( p_mutex );
345 suspend_thread( p_condvar->thread );
346 p_condvar->thread = -1;
348 vlc_mutex_lock( p_mutex );
354 /*****************************************************************************
355 * vlc_cond_timedwait: wait until condition completion or expiration
356 *****************************************************************************
357 * Returns 0 if object signaled, an error code in case of timeout or error.
358 *****************************************************************************/
359 #define vlc_cond_timedwait( P_COND, P_MUTEX, DEADLINE ) \
360 __vlc_cond_timedwait( __FILE__, __LINE__, P_COND, P_MUTEX, DEADLINE )
362 static inline int __vlc_cond_timedwait( const char * psz_file, int i_line,
363 vlc_cond_t *p_condvar,
364 vlc_mutex_t *p_mutex,
367 #if defined(LIBVLC_USE_PTHREAD)
368 lldiv_t d = lldiv( deadline, 1000000 );
369 struct timespec ts = { d.quot, d.rem * 1000 };
371 int val = pthread_cond_timedwait (p_condvar, p_mutex, &ts);
372 if (val == ETIMEDOUT)
373 return ETIMEDOUT; /* this error is perfectly normal */
374 VLC_THREAD_ASSERT ("timed-waiting on condition");
376 #elif defined( UNDER_CE )
377 mtime_t delay_ms = (deadline - mdate())/1000;
382 LeaveCriticalSection( &p_mutex->csection );
383 result = WaitForSingleObject( *p_condvar, delay_ms );
385 /* Reacquire the mutex before returning. */
386 vlc_mutex_lock( p_mutex );
388 if(result == WAIT_TIMEOUT)
389 return ETIMEDOUT; /* this error is perfectly normal */
391 (void)psz_file; (void)i_line;
393 #elif defined( WIN32 )
394 mtime_t total = (deadline - mdate())/1000;
401 DWORD delay = (total > 0x7fffffff) ? 0x7fffffff : total;
402 result = SignalObjectAndWait( *p_mutex, *p_condvar,
405 vlc_mutex_lock (p_mutex);
409 /* Reacquire the mutex before returning. */
410 if(result == WAIT_TIMEOUT)
411 return ETIMEDOUT; /* this error is perfectly normal */
413 (void)psz_file; (void)i_line;
415 #elif defined( SYS_BEOS )
416 # error Unimplemented
423 /*****************************************************************************
424 * vlc_cond_destroy: destroy a condition
425 *****************************************************************************/
426 #define vlc_cond_destroy( P_COND ) \
427 __vlc_cond_destroy( __FILE__, __LINE__, P_COND )
429 /*****************************************************************************
430 * vlc_threadvar_set: create: set the value of a thread-local variable
431 *****************************************************************************/
432 static inline int vlc_threadvar_set( vlc_threadvar_t * p_tls, void *p_value )
436 #if defined(LIBVLC_USE_PTHREAD)
437 i_ret = pthread_setspecific( *p_tls, p_value );
439 #elif defined( SYS_BEOS )
442 #elif defined( UNDER_CE ) || defined( WIN32 )
443 i_ret = TlsSetValue( *p_tls, p_value ) ? EINVAL : 0;
450 /*****************************************************************************
451 * vlc_threadvar_get: create: get the value of a thread-local variable
452 *****************************************************************************/
453 static inline void* vlc_threadvar_get( vlc_threadvar_t * p_tls )
457 #if defined(LIBVLC_USE_PTHREAD)
458 p_ret = pthread_getspecific( *p_tls );
460 #elif defined( SYS_BEOS )
463 #elif defined( UNDER_CE ) || defined( WIN32 )
464 p_ret = TlsGetValue( *p_tls );
471 # if defined (_POSIX_SPIN_LOCKS) && ((_POSIX_SPIN_LOCKS - 0) > 0)
472 typedef pthread_spinlock_t vlc_spinlock_t;
475 * Initializes a spinlock.
477 static inline int vlc_spin_init (vlc_spinlock_t *spin)
479 return pthread_spin_init (spin, PTHREAD_PROCESS_PRIVATE);
483 * Acquires a spinlock.
485 static inline void vlc_spin_lock (vlc_spinlock_t *spin)
487 pthread_spin_lock (spin);
491 * Releases a spinlock.
493 static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
495 pthread_spin_unlock (spin);
499 * Deinitializes a spinlock.
501 static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
503 pthread_spin_destroy (spin);
506 #elif defined( WIN32 )
508 typedef CRITICAL_SECTION vlc_spinlock_t;
511 * Initializes a spinlock.
513 static inline int vlc_spin_init (vlc_spinlock_t *spin)
515 return !InitializeCriticalSectionAndSpinCount(spin, 4000);
519 * Acquires a spinlock.
521 static inline void vlc_spin_lock (vlc_spinlock_t *spin)
523 EnterCriticalSection(spin);
527 * Releases a spinlock.
529 static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
531 LeaveCriticalSection(spin);
535 * Deinitializes a spinlock.
537 static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
539 DeleteCriticalSection(spin);
544 /* Fallback to plain mutexes if spinlocks are not available */
545 typedef vlc_mutex_t vlc_spinlock_t;
547 static inline int vlc_spin_init (vlc_spinlock_t *spin)
549 return vlc_mutex_init (spin);
552 # define vlc_spin_lock vlc_mutex_lock
553 # define vlc_spin_unlock vlc_mutex_unlock
554 # define vlc_spin_destroy vlc_mutex_destroy
558 * Issues a full memory barrier.
560 #if defined (__APPLE__)
561 # include <libkern/OSAtomic.h> /* OSMemoryBarrier() */
563 static inline void barrier (void)
565 #if defined (__GNUC__) && (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)
566 __sync_synchronize ();
567 #elif defined(__APPLE__)
569 #elif defined(__powerpc__)
570 asm volatile ("sync":::"memory");
571 #elif defined(__i386__)
572 asm volatile ("mfence":::"memory");
575 vlc_spin_init (&spin);
576 vlc_spin_lock (&spin);
577 vlc_spin_unlock (&spin);
578 vlc_spin_destroy (&spin);
582 /*****************************************************************************
583 * vlc_thread_create: create a thread
584 *****************************************************************************/
585 #define vlc_thread_create( P_THIS, PSZ_NAME, FUNC, PRIORITY, WAIT ) \
586 __vlc_thread_create( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, FUNC, PRIORITY, WAIT )
588 /*****************************************************************************
589 * vlc_thread_set_priority: set the priority of the calling thread
590 *****************************************************************************/
591 #define vlc_thread_set_priority( P_THIS, PRIORITY ) \
592 __vlc_thread_set_priority( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PRIORITY )
594 /*****************************************************************************
595 * vlc_thread_join: wait until a thread exits
596 *****************************************************************************/
597 #define vlc_thread_join( P_THIS ) \
598 __vlc_thread_join( VLC_OBJECT(P_THIS), __FILE__, __LINE__ )
600 #endif /* !_VLC_THREADS_H */