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 BOOL (WINAPI *SIGNALOBJECTANDWAIT) ( HANDLE, HANDLE, DWORD, BOOL );
127 typedef HANDLE vlc_mutex_t;
128 typedef HANDLE vlc_cond_t;
129 typedef DWORD vlc_threadvar_t;
131 #elif defined( SYS_BEOS )
132 /* This is the BeOS implementation of the vlc threads, note that the mutex is
133 * not a real mutex and the cond_var is not like a pthread cond_var but it is
134 * enough for what we need */
136 typedef thread_id vlc_thread_t;
156 #if defined( WIN32 ) && !defined ETIMEDOUT
157 # define ETIMEDOUT 10060 /* This is the value in winsock.h. */
160 /*****************************************************************************
161 * Function definitions
162 *****************************************************************************/
163 VLC_EXPORT( int, vlc_mutex_init, ( vlc_mutex_t * ) );
164 VLC_EXPORT( int, vlc_mutex_init_recursive, ( vlc_mutex_t * ) );
165 VLC_EXPORT( void, __vlc_mutex_destroy, ( const char *, int, vlc_mutex_t * ) );
166 VLC_EXPORT( int, __vlc_cond_init, ( vlc_cond_t * ) );
167 VLC_EXPORT( void, __vlc_cond_destroy, ( const char *, int, vlc_cond_t * ) );
168 VLC_EXPORT( int, vlc_threadvar_create, (vlc_threadvar_t * , void (*) (void *) ) );
169 VLC_EXPORT( void, vlc_threadvar_delete, (vlc_threadvar_t *) );
170 VLC_EXPORT( int, __vlc_thread_create, ( vlc_object_t *, const char *, int, const char *, void * ( * ) ( vlc_object_t * ), int, bool ) );
171 VLC_EXPORT( int, __vlc_thread_set_priority, ( vlc_object_t *, const char *, int, int ) );
172 VLC_EXPORT( void, __vlc_thread_join, ( vlc_object_t *, const char *, int ) );
174 #define vlc_thread_ready vlc_object_signal
176 /*****************************************************************************
177 * vlc_mutex_lock: lock a mutex
178 *****************************************************************************/
179 #define vlc_mutex_lock( P_MUTEX ) \
180 __vlc_mutex_lock( __FILE__, __LINE__, P_MUTEX )
182 VLC_EXPORT(void, vlc_pthread_fatal, (const char *action, int error, const char *file, unsigned line));
184 #if defined(LIBVLC_USE_PTHREAD)
185 # define VLC_THREAD_ASSERT( action ) \
187 vlc_pthread_fatal (action, val, psz_file, i_line)
189 # define VLC_THREAD_ASSERT ((void)(val))
192 static inline void __vlc_mutex_lock( const char * psz_file, int i_line,
193 vlc_mutex_t * p_mutex )
195 #if defined(LIBVLC_USE_PTHREAD)
196 # define vlc_assert_locked( m ) \
197 assert (pthread_mutex_lock (m) == EDEADLK)
198 int val = pthread_mutex_lock( p_mutex );
199 VLC_THREAD_ASSERT ("locking mutex");
201 #elif defined( UNDER_CE )
202 (void)psz_file; (void)i_line;
204 EnterCriticalSection( &p_mutex->csection );
206 #elif defined( WIN32 )
207 (void)psz_file; (void)i_line;
209 WaitForSingleObject( *p_mutex, INFINITE );
211 #elif defined( SYS_BEOS )
212 acquire_sem( p_mutex->lock );
217 #ifndef vlc_assert_locked
218 # define vlc_assert_locked( m ) (void)m
221 /*****************************************************************************
222 * vlc_mutex_unlock: unlock a mutex
223 *****************************************************************************/
224 #define vlc_mutex_unlock( P_MUTEX ) \
225 __vlc_mutex_unlock( __FILE__, __LINE__, P_MUTEX )
227 static inline void __vlc_mutex_unlock( const char * psz_file, int i_line,
228 vlc_mutex_t *p_mutex )
230 #if defined(LIBVLC_USE_PTHREAD)
231 int val = pthread_mutex_unlock( p_mutex );
232 VLC_THREAD_ASSERT ("unlocking mutex");
234 #elif defined( UNDER_CE )
235 (void)psz_file; (void)i_line;
237 LeaveCriticalSection( &p_mutex->csection );
239 #elif defined( WIN32 )
240 (void)psz_file; (void)i_line;
242 ReleaseMutex( *p_mutex );
244 #elif defined( SYS_BEOS )
245 release_sem( p_mutex->lock );
250 /*****************************************************************************
251 * vlc_mutex_destroy: destroy a mutex
252 *****************************************************************************/
253 #define vlc_mutex_destroy( P_MUTEX ) \
254 __vlc_mutex_destroy( __FILE__, __LINE__, P_MUTEX )
256 /*****************************************************************************
257 * vlc_cond_init: initialize a condition
258 *****************************************************************************/
259 #define vlc_cond_init( P_THIS, P_COND ) \
260 __vlc_cond_init( P_COND )
262 /*****************************************************************************
263 * vlc_cond_signal: start a thread on condition completion
264 *****************************************************************************/
265 #define vlc_cond_signal( P_COND ) \
266 __vlc_cond_signal( __FILE__, __LINE__, P_COND )
268 static inline void __vlc_cond_signal( const char * psz_file, int i_line,
269 vlc_cond_t *p_condvar )
271 #if defined(LIBVLC_USE_PTHREAD)
272 int val = pthread_cond_signal( p_condvar );
273 VLC_THREAD_ASSERT ("signaling condition variable");
275 #elif defined( UNDER_CE ) || defined( WIN32 )
276 (void)psz_file; (void)i_line;
278 /* Release one waiting thread if one is available. */
279 /* For this trick to work properly, the vlc_cond_signal must be surrounded
280 * by a mutex. This will prevent another thread from stealing the signal */
281 /* PulseEvent() only works if none of the waiting threads is suspended.
282 * This is particularily problematic under a debug session.
283 * as documented in http://support.microsoft.com/kb/q173260/ */
284 PulseEvent( *p_condvar );
286 #elif defined( SYS_BEOS )
287 while( p_condvar->thread != -1 )
290 if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE )
293 if( info.state != B_THREAD_SUSPENDED )
295 /* The waiting thread is not suspended so it could
296 * have been interrupted beetwen the unlock and the
297 * suspend_thread line. That is why we sleep a little
298 * before retesting p_condver->thread. */
303 /* Ok, we have to wake up that thread */
304 resume_thread( p_condvar->thread );
311 /*****************************************************************************
312 * vlc_cond_wait: wait until condition completion
313 *****************************************************************************/
314 #define vlc_cond_wait( P_COND, P_MUTEX ) \
315 __vlc_cond_wait( __FILE__, __LINE__, P_COND, P_MUTEX )
317 static inline void __vlc_cond_wait( const char * psz_file, int i_line,
318 vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex )
320 #if defined(LIBVLC_USE_PTHREAD)
321 int val = pthread_cond_wait( p_condvar, p_mutex );
322 VLC_THREAD_ASSERT ("waiting on condition");
324 #elif defined( UNDER_CE )
325 LeaveCriticalSection( &p_mutex->csection );
326 WaitForSingleObject( *p_condvar, INFINITE );
328 /* Reacquire the mutex before returning. */
329 vlc_mutex_lock( p_mutex );
331 #elif defined( WIN32 )
332 (void)psz_file; (void)i_line;
334 /* Increase our wait count */
335 SignalObjectAndWait( *p_mutex, *p_condvar, INFINITE, FALSE );
337 /* Reacquire the mutex before returning. */
338 vlc_mutex_lock( p_mutex );
340 #elif defined( SYS_BEOS )
341 /* The p_condvar->thread var is initialized before the unlock because
342 * it enables to identify when the thread is interrupted beetwen the
343 * unlock line and the suspend_thread line */
344 p_condvar->thread = find_thread( NULL );
345 vlc_mutex_unlock( p_mutex );
346 suspend_thread( p_condvar->thread );
347 p_condvar->thread = -1;
349 vlc_mutex_lock( p_mutex );
355 /*****************************************************************************
356 * vlc_cond_timedwait: wait until condition completion or expiration
357 *****************************************************************************
358 * Returns 0 if object signaled, an error code in case of timeout or error.
359 *****************************************************************************/
360 #define vlc_cond_timedwait( P_COND, P_MUTEX, DEADLINE ) \
361 __vlc_cond_timedwait( __FILE__, __LINE__, P_COND, P_MUTEX, DEADLINE )
363 static inline int __vlc_cond_timedwait( const char * psz_file, int i_line,
364 vlc_cond_t *p_condvar,
365 vlc_mutex_t *p_mutex,
368 #if defined(LIBVLC_USE_PTHREAD)
369 lldiv_t d = lldiv( deadline, 1000000 );
370 struct timespec ts = { d.quot, d.rem * 1000 };
372 int val = pthread_cond_timedwait (p_condvar, p_mutex, &ts);
373 if (val == ETIMEDOUT)
374 return ETIMEDOUT; /* this error is perfectly normal */
375 VLC_THREAD_ASSERT ("timed-waiting on condition");
377 #elif defined( UNDER_CE )
378 mtime_t delay_ms = (deadline - mdate())/1000;
383 LeaveCriticalSection( &p_mutex->csection );
384 result = WaitForSingleObject( *p_condvar, delay_ms );
386 /* Reacquire the mutex before returning. */
387 vlc_mutex_lock( p_mutex );
389 if(result == WAIT_TIMEOUT)
390 return ETIMEDOUT; /* this error is perfectly normal */
392 (void)psz_file; (void)i_line;
394 #elif defined( WIN32 )
395 mtime_t total = (deadline - mdate())/1000;
402 DWORD delay = (total > 0x7fffffff) ? 0x7fffffff : total;
403 result = SignalObjectAndWait( *p_mutex, *p_condvar,
406 vlc_mutex_lock (p_mutex);
410 /* Reacquire the mutex before returning. */
411 if(result == WAIT_TIMEOUT)
412 return ETIMEDOUT; /* this error is perfectly normal */
414 (void)psz_file; (void)i_line;
416 #elif defined( SYS_BEOS )
417 # error Unimplemented
424 /*****************************************************************************
425 * vlc_cond_destroy: destroy a condition
426 *****************************************************************************/
427 #define vlc_cond_destroy( P_COND ) \
428 __vlc_cond_destroy( __FILE__, __LINE__, P_COND )
430 /*****************************************************************************
431 * vlc_threadvar_set: create: set the value of a thread-local variable
432 *****************************************************************************/
433 static inline int vlc_threadvar_set( vlc_threadvar_t * p_tls, void *p_value )
437 #if defined(LIBVLC_USE_PTHREAD)
438 i_ret = pthread_setspecific( *p_tls, p_value );
440 #elif defined( SYS_BEOS )
443 #elif defined( UNDER_CE ) || defined( WIN32 )
444 i_ret = TlsSetValue( *p_tls, p_value ) ? EINVAL : 0;
451 /*****************************************************************************
452 * vlc_threadvar_get: create: get the value of a thread-local variable
453 *****************************************************************************/
454 static inline void* vlc_threadvar_get( vlc_threadvar_t * p_tls )
458 #if defined(LIBVLC_USE_PTHREAD)
459 p_ret = pthread_getspecific( *p_tls );
461 #elif defined( SYS_BEOS )
464 #elif defined( UNDER_CE ) || defined( WIN32 )
465 p_ret = TlsGetValue( *p_tls );
472 # if defined (_POSIX_SPIN_LOCKS) && ((_POSIX_SPIN_LOCKS - 0) > 0)
473 typedef pthread_spinlock_t vlc_spinlock_t;
476 * Initializes a spinlock.
478 static inline int vlc_spin_init (vlc_spinlock_t *spin)
480 return pthread_spin_init (spin, PTHREAD_PROCESS_PRIVATE);
484 * Acquires a spinlock.
486 static inline void vlc_spin_lock (vlc_spinlock_t *spin)
488 pthread_spin_lock (spin);
492 * Releases a spinlock.
494 static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
496 pthread_spin_unlock (spin);
500 * Deinitializes a spinlock.
502 static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
504 pthread_spin_destroy (spin);
507 #elif defined( WIN32 )
509 typedef CRITICAL_SECTION vlc_spinlock_t;
512 * Initializes a spinlock.
514 static inline int vlc_spin_init (vlc_spinlock_t *spin)
516 return !InitializeCriticalSectionAndSpinCount(spin, 4000);
520 * Acquires a spinlock.
522 static inline void vlc_spin_lock (vlc_spinlock_t *spin)
524 EnterCriticalSection(spin);
528 * Releases a spinlock.
530 static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
532 LeaveCriticalSection(spin);
536 * Deinitializes a spinlock.
538 static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
540 DeleteCriticalSection(spin);
545 /* Fallback to plain mutexes if spinlocks are not available */
546 typedef vlc_mutex_t vlc_spinlock_t;
548 static inline int vlc_spin_init (vlc_spinlock_t *spin)
550 return vlc_mutex_init (spin);
553 # define vlc_spin_lock vlc_mutex_lock
554 # define vlc_spin_unlock vlc_mutex_unlock
555 # define vlc_spin_destroy vlc_mutex_destroy
559 * Issues a full memory barrier.
561 #if defined (__APPLE__)
562 # include <libkern/OSAtomic.h> /* OSMemoryBarrier() */
564 static inline void barrier (void)
566 #if defined (__GNUC__) && (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)
567 __sync_synchronize ();
568 #elif defined(__APPLE__)
570 #elif defined(__powerpc__)
571 asm volatile ("sync":::"memory");
572 #elif defined(__i386__)
573 asm volatile ("mfence":::"memory");
576 vlc_spin_init (&spin);
577 vlc_spin_lock (&spin);
578 vlc_spin_unlock (&spin);
579 vlc_spin_destroy (&spin);
583 /*****************************************************************************
584 * vlc_thread_create: create a thread
585 *****************************************************************************/
586 #define vlc_thread_create( P_THIS, PSZ_NAME, FUNC, PRIORITY, WAIT ) \
587 __vlc_thread_create( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, FUNC, PRIORITY, WAIT )
589 /*****************************************************************************
590 * vlc_thread_set_priority: set the priority of the calling thread
591 *****************************************************************************/
592 #define vlc_thread_set_priority( P_THIS, PRIORITY ) \
593 __vlc_thread_set_priority( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PRIORITY )
595 /*****************************************************************************
596 * vlc_thread_join: wait until a thread exits
597 *****************************************************************************/
598 #define vlc_thread_join( P_THIS ) \
599 __vlc_thread_join( VLC_OBJECT(P_THIS), __FILE__, __LINE__ )
601 #endif /* !_VLC_THREADS_H */