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
6 * Copyright © 2007-2008 Rémi Denis-Courmont
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 )
38 #elif defined( WIN32 )
39 # include <process.h> /* Win32 API */
41 #else /* pthreads (like Linux & BSD) */
42 # define LIBVLC_USE_PTHREAD 1
43 # define LIBVLC_USE_PTHREAD_CANCEL 1
44 # define _APPLE_C_SOURCE 1 /* Proper pthread semantics on OSX */
46 # include <unistd.h> /* _POSIX_SPIN_LOCKS */
49 /* Unnamed POSIX semaphores not supported on Mac OS X, use Mach semaphores instead */
50 # if defined (__APPLE__)
51 # include <mach/semaphore.h>
52 # include <mach/task.h>
54 # include <semaphore.h>
59 /*****************************************************************************
61 *****************************************************************************/
63 /* Thread priorities */
65 # define VLC_THREAD_PRIORITY_LOW 0
66 # define VLC_THREAD_PRIORITY_INPUT 22
67 # define VLC_THREAD_PRIORITY_AUDIO 22
68 # define VLC_THREAD_PRIORITY_VIDEO 0
69 # define VLC_THREAD_PRIORITY_OUTPUT 22
70 # define VLC_THREAD_PRIORITY_HIGHEST 22
72 #elif defined(LIBVLC_USE_PTHREAD)
73 # define VLC_THREAD_PRIORITY_LOW 0
74 # define VLC_THREAD_PRIORITY_INPUT 10
75 # define VLC_THREAD_PRIORITY_AUDIO 5
76 # define VLC_THREAD_PRIORITY_VIDEO 0
77 # define VLC_THREAD_PRIORITY_OUTPUT 15
78 # define VLC_THREAD_PRIORITY_HIGHEST 20
80 #elif defined(WIN32) || defined(UNDER_CE)
81 /* Define different priorities for WinNT/2K/XP and Win9x/Me */
82 # define VLC_THREAD_PRIORITY_LOW 0
83 # define VLC_THREAD_PRIORITY_INPUT \
84 THREAD_PRIORITY_ABOVE_NORMAL
85 # define VLC_THREAD_PRIORITY_AUDIO \
86 THREAD_PRIORITY_HIGHEST
87 # define VLC_THREAD_PRIORITY_VIDEO 0
88 # define VLC_THREAD_PRIORITY_OUTPUT \
89 THREAD_PRIORITY_ABOVE_NORMAL
90 # define VLC_THREAD_PRIORITY_HIGHEST \
91 THREAD_PRIORITY_TIME_CRITICAL
94 # define VLC_THREAD_PRIORITY_LOW 0
95 # define VLC_THREAD_PRIORITY_INPUT 0
96 # define VLC_THREAD_PRIORITY_AUDIO 0
97 # define VLC_THREAD_PRIORITY_VIDEO 0
98 # define VLC_THREAD_PRIORITY_OUTPUT 0
99 # define VLC_THREAD_PRIORITY_HIGHEST 0
103 /*****************************************************************************
105 *****************************************************************************/
107 #if defined (LIBVLC_USE_PTHREAD)
108 typedef pthread_t vlc_thread_t;
109 typedef pthread_mutex_t vlc_mutex_t;
110 #define VLC_STATIC_MUTEX PTHREAD_MUTEX_INITIALIZER
111 typedef pthread_cond_t vlc_cond_t;
112 #define VLC_STATIC_COND PTHREAD_COND_INITIALIZER
113 typedef pthread_rwlock_t vlc_rwlock_t;
114 typedef pthread_key_t vlc_threadvar_t;
115 typedef struct vlc_timer *vlc_timer_t;
117 #if defined (__APPLE__)
118 typedef semaphore_t vlc_sem_t;
120 typedef sem_t vlc_sem_t;
123 #elif defined( WIN32 )
124 typedef struct vlc_thread *vlc_thread_t;
134 unsigned long contention;
136 CRITICAL_SECTION mutex;
139 #define VLC_STATIC_MUTEX { false, { { false, 0 } } }
147 typedef HANDLE vlc_sem_t;
152 vlc_cond_t read_wait;
153 vlc_cond_t write_wait;
154 unsigned long readers;
155 unsigned long writers;
159 typedef struct vlc_threadvar *vlc_threadvar_t;
160 typedef struct vlc_timer *vlc_timer_t;
163 #if defined( WIN32 ) && !defined ETIMEDOUT
164 # define ETIMEDOUT 10060 /* This is the value in winsock.h. */
167 /*****************************************************************************
168 * Function definitions
169 *****************************************************************************/
170 VLC_EXPORT( void, vlc_mutex_init, ( vlc_mutex_t * ) );
171 VLC_EXPORT( void, vlc_mutex_init_recursive, ( vlc_mutex_t * ) );
172 VLC_EXPORT( void, vlc_mutex_destroy, ( vlc_mutex_t * ) );
173 VLC_EXPORT( void, vlc_mutex_lock, ( vlc_mutex_t * ) );
174 VLC_EXPORT( int, vlc_mutex_trylock, ( vlc_mutex_t * ) LIBVLC_USED );
175 VLC_EXPORT( void, vlc_mutex_unlock, ( vlc_mutex_t * ) );
176 VLC_EXPORT( void, vlc_cond_init, ( vlc_cond_t * ) );
177 VLC_EXPORT( void, vlc_cond_init_daytime, ( vlc_cond_t * ) );
178 VLC_EXPORT( void, vlc_cond_destroy, ( vlc_cond_t * ) );
179 VLC_EXPORT( void, vlc_cond_signal, (vlc_cond_t *) );
180 VLC_EXPORT( void, vlc_cond_broadcast, (vlc_cond_t *) );
181 VLC_EXPORT( void, vlc_cond_wait, (vlc_cond_t *, vlc_mutex_t *) );
182 VLC_EXPORT( int, vlc_cond_timedwait, (vlc_cond_t *, vlc_mutex_t *, mtime_t) );
183 VLC_EXPORT( void, vlc_sem_init, (vlc_sem_t *, unsigned) );
184 VLC_EXPORT( void, vlc_sem_destroy, (vlc_sem_t *) );
185 VLC_EXPORT( int, vlc_sem_post, (vlc_sem_t *) );
186 VLC_EXPORT( void, vlc_sem_wait, (vlc_sem_t *) );
188 VLC_EXPORT( void, vlc_rwlock_init, (vlc_rwlock_t *) );
189 VLC_EXPORT( void, vlc_rwlock_destroy, (vlc_rwlock_t *) );
190 VLC_EXPORT( void, vlc_rwlock_rdlock, (vlc_rwlock_t *) );
191 VLC_EXPORT( void, vlc_rwlock_wrlock, (vlc_rwlock_t *) );
192 VLC_EXPORT( void, vlc_rwlock_unlock, (vlc_rwlock_t *) );
193 VLC_EXPORT( int, vlc_threadvar_create, (vlc_threadvar_t * , void (*) (void *) ) );
194 VLC_EXPORT( void, vlc_threadvar_delete, (vlc_threadvar_t *) );
195 VLC_EXPORT( int, vlc_threadvar_set, (vlc_threadvar_t, void *) );
196 VLC_EXPORT( void *, vlc_threadvar_get, (vlc_threadvar_t) );
197 #if defined (__GNUC__) && !defined __cplusplus
198 __attribute__((deprecated))
200 VLC_EXPORT( int, vlc_thread_create, ( vlc_object_t *, void * ( * ) ( vlc_object_t * ), int ) LIBVLC_USED );
201 #if defined (__GNUC__) && !defined __cplusplus
202 __attribute__((deprecated))
204 VLC_EXPORT( int, vlc_thread_set_priority, ( vlc_object_t *, int ) );
205 #if defined (__GNUC__) && !defined __cplusplus
206 __attribute__((deprecated))
208 VLC_EXPORT( void, vlc_thread_join, ( vlc_object_t * ) );
210 VLC_EXPORT( int, vlc_clone, (vlc_thread_t *, void * (*) (void *), void *, int) LIBVLC_USED );
211 VLC_EXPORT( void, vlc_cancel, (vlc_thread_t) );
212 VLC_EXPORT( void, vlc_join, (vlc_thread_t, void **) );
213 VLC_EXPORT (void, vlc_control_cancel, (int cmd, ...));
215 VLC_EXPORT( int, vlc_timer_create, (vlc_timer_t *, void (*) (void *), void *) LIBVLC_USED );
216 VLC_EXPORT( void, vlc_timer_destroy, (vlc_timer_t) );
217 VLC_EXPORT( void, vlc_timer_schedule, (vlc_timer_t, bool, mtime_t, mtime_t) );
218 VLC_EXPORT( unsigned, vlc_timer_getoverrun, (vlc_timer_t) LIBVLC_USED );
220 #ifndef LIBVLC_USE_PTHREAD_CANCEL
227 VLC_EXPORT( int, vlc_savecancel, (void) );
228 VLC_EXPORT( void, vlc_restorecancel, (int state) );
229 VLC_EXPORT( void, vlc_testcancel, (void) );
231 #if defined (LIBVLC_USE_PTHREAD_CANCEL)
233 * Registers a new procedure to run if the thread is cancelled (or otherwise
234 * exits prematurely). Any call to vlc_cleanup_push() <b>must</b> paired with a
235 * call to either vlc_cleanup_pop() or vlc_cleanup_run(). Branching into or out
236 * of the block between these two function calls is not allowed (read: it will
237 * likely crash the whole process). If multiple procedures are registered,
238 * they are handled in last-in first-out order.
240 * @param routine procedure to call if the thread ends
241 * @param arg argument for the procedure
243 # define vlc_cleanup_push( routine, arg ) pthread_cleanup_push (routine, arg)
246 * Removes a cleanup procedure that was previously registered with
247 * vlc_cleanup_push().
249 # define vlc_cleanup_pop( ) pthread_cleanup_pop (0)
252 * Removes a cleanup procedure that was previously registered with
253 * vlc_cleanup_push(), and executes it.
255 # define vlc_cleanup_run( ) pthread_cleanup_pop (1)
257 typedef struct vlc_cleanup_t vlc_cleanup_t;
262 void (*proc) (void *);
266 /* This macros opens a code block on purpose. This is needed for multiple
267 * calls within a single function. This also prevent Win32 developers from
268 * writing code that would break on POSIX (POSIX opens a block as well). */
269 # define vlc_cleanup_push( routine, arg ) \
271 vlc_cleanup_t vlc_cleanup_data = { NULL, routine, arg, }; \
272 vlc_control_cancel (VLC_CLEANUP_PUSH, &vlc_cleanup_data)
274 # define vlc_cleanup_pop( ) \
275 vlc_control_cancel (VLC_CLEANUP_POP); \
278 # define vlc_cleanup_run( ) \
279 vlc_control_cancel (VLC_CLEANUP_POP); \
280 vlc_cleanup_data.proc (vlc_cleanup_data.data); \
283 #endif /* LIBVLC_USE_PTHREAD_CANCEL */
285 static inline void vlc_cleanup_lock (void *lock)
287 vlc_mutex_unlock ((vlc_mutex_t *)lock);
289 #define mutex_cleanup_push( lock ) vlc_cleanup_push (vlc_cleanup_lock, lock)
291 # if defined (_POSIX_SPIN_LOCKS) && ((_POSIX_SPIN_LOCKS - 0) > 0)
292 typedef pthread_spinlock_t vlc_spinlock_t;
295 * Initializes a spinlock.
297 static inline void vlc_spin_init (vlc_spinlock_t *spin)
299 if (pthread_spin_init (spin, PTHREAD_PROCESS_PRIVATE))
304 * Acquires a spinlock.
306 static inline void vlc_spin_lock (vlc_spinlock_t *spin)
308 pthread_spin_lock (spin);
312 * Releases a spinlock.
314 static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
316 pthread_spin_unlock (spin);
320 * Deinitializes a spinlock.
322 static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
324 pthread_spin_destroy (spin);
327 #elif defined (WIN32) && !defined (UNDER_CE)
329 typedef CRITICAL_SECTION vlc_spinlock_t;
332 * Initializes a spinlock.
334 static inline void vlc_spin_init (vlc_spinlock_t *spin)
336 if (!InitializeCriticalSectionAndSpinCount(spin, 4000))
341 * Acquires a spinlock.
343 static inline void vlc_spin_lock (vlc_spinlock_t *spin)
345 EnterCriticalSection(spin);
349 * Releases a spinlock.
351 static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
353 LeaveCriticalSection(spin);
357 * Deinitializes a spinlock.
359 static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
361 DeleteCriticalSection(spin);
366 /* Fallback to plain mutexes if spinlocks are not available */
367 typedef vlc_mutex_t vlc_spinlock_t;
369 static inline void vlc_spin_init (vlc_spinlock_t *spin)
371 vlc_mutex_init (spin);
374 # define vlc_spin_lock vlc_mutex_lock
375 # define vlc_spin_unlock vlc_mutex_unlock
376 # define vlc_spin_destroy vlc_mutex_destroy
380 * Issues a full memory barrier.
382 #if defined (__APPLE__)
383 # include <libkern/OSAtomic.h> /* OSMemoryBarrier() */
385 static inline void barrier (void)
387 #if defined (__GNUC__) && !defined (__APPLE__) && \
388 ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1))
389 __sync_synchronize ();
390 #elif defined(__APPLE__)
392 #elif defined(__powerpc__)
393 asm volatile ("sync":::"memory");
394 #elif 0 // defined(__i386__) /* Requires SSE2 support */
395 asm volatile ("mfence":::"memory");
398 vlc_spin_init (&spin);
399 vlc_spin_lock (&spin);
400 vlc_spin_unlock (&spin);
401 vlc_spin_destroy (&spin);
405 #define vlc_thread_create( P_THIS, FUNC, PRIORITY ) \
406 vlc_thread_create( VLC_OBJECT(P_THIS), FUNC, PRIORITY )
408 #define vlc_thread_set_priority( P_THIS, PRIORITY ) \
409 vlc_thread_set_priority( VLC_OBJECT(P_THIS), PRIORITY )
411 #define vlc_thread_join( P_THIS ) \
412 vlc_thread_join( VLC_OBJECT(P_THIS) )
416 * Helper C++ class to lock a mutex.
417 * The mutex is locked when the object is created, and unlocked when the object
420 class vlc_mutex_locker
425 vlc_mutex_locker (vlc_mutex_t *m) : lock (m)
427 vlc_mutex_lock (lock);
430 ~vlc_mutex_locker (void)
432 vlc_mutex_unlock (lock);
438 VLC_AVCODEC_MUTEX = 0,
441 /* Insert new entry HERE */
445 VLC_EXPORT( void, vlc_global_mutex, ( unsigned, bool ) );
446 #define vlc_global_lock( n ) vlc_global_mutex( n, true )
447 #define vlc_global_unlock( n ) vlc_global_mutex( n, false )
449 #endif /* !_VLC_THREADS_H */