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 VLC_EXPORT( int, vlc_thread_create
, ( vlc_object_t
*, const char *, int, const char *, void * ( * ) ( vlc_object_t
* ), int ) LIBVLC_USED
);
198 VLC_EXPORT( int, vlc_thread_set_priority
, ( vlc_object_t
*, const char *, int, int ) );
199 VLC_EXPORT( void, vlc_thread_join
, ( vlc_object_t
* ) );
201 VLC_EXPORT( int, vlc_clone
, (vlc_thread_t
*, void * (*) (void *), void *, int) LIBVLC_USED
);
202 VLC_EXPORT( void, vlc_cancel
, (vlc_thread_t
) );
203 VLC_EXPORT( void, vlc_join
, (vlc_thread_t
, void **) );
204 VLC_EXPORT (void, vlc_control_cancel
, (int cmd
, ...));
206 VLC_EXPORT( int, vlc_timer_create
, (vlc_timer_t
*, void (*) (void *), void *) LIBVLC_USED
);
207 VLC_EXPORT( void, vlc_timer_destroy
, (vlc_timer_t
) );
208 VLC_EXPORT( void, vlc_timer_schedule
, (vlc_timer_t
, bool, mtime_t
, mtime_t
) );
209 VLC_EXPORT( unsigned, vlc_timer_getoverrun
, (vlc_timer_t
) LIBVLC_USED
);
211 #ifndef LIBVLC_USE_PTHREAD_CANCEL
218 VLC_EXPORT( int, vlc_savecancel
, (void) );
219 VLC_EXPORT( void, vlc_restorecancel
, (int state
) );
220 VLC_EXPORT( void, vlc_testcancel
, (void) );
222 #if defined (LIBVLC_USE_PTHREAD_CANCEL)
224 * Registers a new procedure to run if the thread is cancelled (or otherwise
225 * exits prematurely). Any call to vlc_cleanup_push() <b>must</b> paired with a
226 * call to either vlc_cleanup_pop() or vlc_cleanup_run(). Branching into or out
227 * of the block between these two function calls is not allowed (read: it will
228 * likely crash the whole process). If multiple procedures are registered,
229 * they are handled in last-in first-out order.
231 * @param routine procedure to call if the thread ends
232 * @param arg argument for the procedure
234 # define vlc_cleanup_push( routine, arg ) pthread_cleanup_push (routine, arg)
237 * Removes a cleanup procedure that was previously registered with
238 * vlc_cleanup_push().
240 # define vlc_cleanup_pop( ) pthread_cleanup_pop (0)
243 * Removes a cleanup procedure that was previously registered with
244 * vlc_cleanup_push(), and executes it.
246 # define vlc_cleanup_run( ) pthread_cleanup_pop (1)
248 typedef struct vlc_cleanup_t vlc_cleanup_t
;
253 void (*proc
) (void *);
257 /* This macros opens a code block on purpose. This is needed for multiple
258 * calls within a single function. This also prevent Win32 developers from
259 * writing code that would break on POSIX (POSIX opens a block as well). */
260 # define vlc_cleanup_push( routine, arg ) \
262 vlc_cleanup_t vlc_cleanup_data = { NULL, routine, arg, }; \
263 vlc_control_cancel (VLC_CLEANUP_PUSH, &vlc_cleanup_data)
265 # define vlc_cleanup_pop( ) \
266 vlc_control_cancel (VLC_CLEANUP_POP); \
269 # define vlc_cleanup_run( ) \
270 vlc_control_cancel (VLC_CLEANUP_POP); \
271 vlc_cleanup_data.proc (vlc_cleanup_data.data); \
274 #endif /* LIBVLC_USE_PTHREAD_CANCEL */
276 static inline void vlc_cleanup_lock (void *lock
)
278 vlc_mutex_unlock ((vlc_mutex_t
*)lock
);
280 #define mutex_cleanup_push( lock ) vlc_cleanup_push (vlc_cleanup_lock, lock)
282 # if defined (_POSIX_SPIN_LOCKS) && ((_POSIX_SPIN_LOCKS - 0) > 0)
283 typedef pthread_spinlock_t vlc_spinlock_t
;
286 * Initializes a spinlock.
288 static inline void vlc_spin_init (vlc_spinlock_t
*spin
)
290 if (pthread_spin_init (spin
, PTHREAD_PROCESS_PRIVATE
))
295 * Acquires a spinlock.
297 static inline void vlc_spin_lock (vlc_spinlock_t
*spin
)
299 pthread_spin_lock (spin
);
303 * Releases a spinlock.
305 static inline void vlc_spin_unlock (vlc_spinlock_t
*spin
)
307 pthread_spin_unlock (spin
);
311 * Deinitializes a spinlock.
313 static inline void vlc_spin_destroy (vlc_spinlock_t
*spin
)
315 pthread_spin_destroy (spin
);
318 #elif defined (WIN32) && !defined (UNDER_CE)
320 typedef CRITICAL_SECTION vlc_spinlock_t
;
323 * Initializes a spinlock.
325 static inline void vlc_spin_init (vlc_spinlock_t
*spin
)
327 if (!InitializeCriticalSectionAndSpinCount(spin
, 4000))
332 * Acquires a spinlock.
334 static inline void vlc_spin_lock (vlc_spinlock_t
*spin
)
336 EnterCriticalSection(spin
);
340 * Releases a spinlock.
342 static inline void vlc_spin_unlock (vlc_spinlock_t
*spin
)
344 LeaveCriticalSection(spin
);
348 * Deinitializes a spinlock.
350 static inline void vlc_spin_destroy (vlc_spinlock_t
*spin
)
352 DeleteCriticalSection(spin
);
357 /* Fallback to plain mutexes if spinlocks are not available */
358 typedef vlc_mutex_t vlc_spinlock_t
;
360 static inline void vlc_spin_init (vlc_spinlock_t
*spin
)
362 vlc_mutex_init (spin
);
365 # define vlc_spin_lock vlc_mutex_lock
366 # define vlc_spin_unlock vlc_mutex_unlock
367 # define vlc_spin_destroy vlc_mutex_destroy
371 * Issues a full memory barrier.
373 #if defined (__APPLE__)
374 # include <libkern/OSAtomic.h> /* OSMemoryBarrier() */
376 static inline void barrier (void)
378 #if defined (__GNUC__) && !defined (__APPLE__) && \
379 ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1))
380 __sync_synchronize ();
381 #elif defined(__APPLE__)
383 #elif defined(__powerpc__)
384 asm volatile ("sync":::"memory");
385 #elif 0 // defined(__i386__) /* Requires SSE2 support */
386 asm volatile ("mfence":::"memory");
389 vlc_spin_init (&spin
);
390 vlc_spin_lock (&spin
);
391 vlc_spin_unlock (&spin
);
392 vlc_spin_destroy (&spin
);
396 /*****************************************************************************
397 * vlc_thread_create: create a thread
398 *****************************************************************************/
399 #define vlc_thread_create( P_THIS, PSZ_NAME, FUNC, PRIORITY ) \
400 vlc_thread_create( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, FUNC, PRIORITY )
402 /*****************************************************************************
403 * vlc_thread_set_priority: set the priority of the calling thread
404 *****************************************************************************/
405 #define vlc_thread_set_priority( P_THIS, PRIORITY ) \
406 vlc_thread_set_priority( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PRIORITY )
408 /*****************************************************************************
409 * vlc_thread_join: wait until a thread exits
410 *****************************************************************************/
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 */