vlc_threads.h 13.2 KB
Newer Older
1
/*****************************************************************************
2 3
 * vlc_threads.h : threads implementation for the VideoLAN client
 * This header provides portable declarations for mutexes & conditions
4
 *****************************************************************************
5
 * Copyright (C) 1999, 2002 the VideoLAN team
6
 * Copyright © 2007-2008 Rémi Denis-Courmont
7
 *
8 9
 * Authors: Jean-Marc Dressler <polux@via.ecp.fr>
 *          Samuel Hocevar <sam@via.ecp.fr>
Gildas Bazin's avatar
 
Gildas Bazin committed
10
 *          Gildas Bazin <gbazin@netcourrier.com>
11
 *          Christophe Massiot <massiot@via.ecp.fr>
12 13 14 15 16
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
17
 *
18 19
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 21
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
22
 *
23 24
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
Antoine Cellerier's avatar
Antoine Cellerier committed
25
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
26
 *****************************************************************************/
27

28 29
#ifndef VLC_THREADS_H_
#define VLC_THREADS_H_
30

31 32 33 34 35 36
/**
 * \file
 * This file defines structures and functions for handling threads in vlc
 *
 */

37
#if defined( UNDER_CE )
38 39
#elif defined( WIN32 )
#   include <process.h>                                         /* Win32 API */
Sam Hocevar's avatar
 
Sam Hocevar committed
40

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 */
45

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
46
#   include <unistd.h> /* _POSIX_SPIN_LOCKS */
Sam Hocevar's avatar
 
Sam Hocevar committed
47
#   include <pthread.h>
48 49 50 51 52 53 54 55

/* Unnamed POSIX semaphores not supported on Mac OS X, use Mach semaphores instead */
#   if defined (__APPLE__)
#      include <mach/semaphore.h>
#      include <mach/task.h>
#   else
#      include <semaphore.h>
#   endif
56

57
#endif
58

59
/*****************************************************************************
Vincent Seguin's avatar
Vincent Seguin committed
60
 * Constants
61
 *****************************************************************************/
Vincent Seguin's avatar
Vincent Seguin committed
62

63
/* Thread priorities */
64
#ifdef __APPLE__
65 66 67 68 69 70
#   define VLC_THREAD_PRIORITY_LOW      0
#   define VLC_THREAD_PRIORITY_INPUT   22
#   define VLC_THREAD_PRIORITY_AUDIO   22
#   define VLC_THREAD_PRIORITY_VIDEO    0
#   define VLC_THREAD_PRIORITY_OUTPUT  22
#   define VLC_THREAD_PRIORITY_HIGHEST 22
Vincent Seguin's avatar
Vincent Seguin committed
71

72
#elif defined(LIBVLC_USE_PTHREAD)
73 74 75 76 77 78
#   define VLC_THREAD_PRIORITY_LOW      0
#   define VLC_THREAD_PRIORITY_INPUT   10
#   define VLC_THREAD_PRIORITY_AUDIO    5
#   define VLC_THREAD_PRIORITY_VIDEO    0
#   define VLC_THREAD_PRIORITY_OUTPUT  15
#   define VLC_THREAD_PRIORITY_HIGHEST 20
79

80
#elif defined(WIN32) || defined(UNDER_CE)
Gildas Bazin's avatar
 
Gildas Bazin committed
81
/* Define different priorities for WinNT/2K/XP and Win9x/Me */
82
#   define VLC_THREAD_PRIORITY_LOW 0
Gildas Bazin's avatar
 
Gildas Bazin committed
83
#   define VLC_THREAD_PRIORITY_INPUT \
Geoffroy Couprie's avatar
Geoffroy Couprie committed
84
        THREAD_PRIORITY_ABOVE_NORMAL
Gildas Bazin's avatar
 
Gildas Bazin committed
85
#   define VLC_THREAD_PRIORITY_AUDIO \
Geoffroy Couprie's avatar
Geoffroy Couprie committed
86 87
        THREAD_PRIORITY_HIGHEST
#   define VLC_THREAD_PRIORITY_VIDEO 0
Gildas Bazin's avatar
 
Gildas Bazin committed
88
#   define VLC_THREAD_PRIORITY_OUTPUT \
Geoffroy Couprie's avatar
Geoffroy Couprie committed
89
        THREAD_PRIORITY_ABOVE_NORMAL
Gildas Bazin's avatar
 
Gildas Bazin committed
90
#   define VLC_THREAD_PRIORITY_HIGHEST \
Geoffroy Couprie's avatar
Geoffroy Couprie committed
91
        THREAD_PRIORITY_TIME_CRITICAL
92

93 94 95 96
#else
#   define VLC_THREAD_PRIORITY_LOW 0
#   define VLC_THREAD_PRIORITY_INPUT 0
#   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
Vincent Seguin's avatar
Vincent Seguin committed
100

101
#endif
Vincent Seguin's avatar
Vincent Seguin committed
102

103
/*****************************************************************************
Gildas Bazin's avatar
 
Gildas Bazin committed
104
 * Type definitions
105
 *****************************************************************************/
106

107 108 109
#if defined (LIBVLC_USE_PTHREAD)
typedef pthread_t       vlc_thread_t;
typedef pthread_mutex_t vlc_mutex_t;
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
110
#define VLC_STATIC_MUTEX PTHREAD_MUTEX_INITIALIZER
111
typedef pthread_cond_t  vlc_cond_t;
112
#define VLC_STATIC_COND  PTHREAD_COND_INITIALIZER
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
113
typedef pthread_rwlock_t vlc_rwlock_t;
114
typedef pthread_key_t   vlc_threadvar_t;
115
typedef struct vlc_timer *vlc_timer_t;
116

117 118 119 120 121 122
#if defined (__APPLE__)
typedef semaphore_t     vlc_sem_t;
#else
typedef sem_t           vlc_sem_t;
#endif

123
#elif defined( WIN32 )
124
typedef struct vlc_thread *vlc_thread_t;
125

126 127
typedef struct
{
128 129 130
    bool dynamic;
    union
    {
131 132 133 134 135
        struct
        {
            bool locked;
            unsigned long contention;
        };
136 137
        CRITICAL_SECTION mutex;
    };
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
138
} vlc_mutex_t;
139
#define VLC_STATIC_MUTEX { false, { { false, 0 } } }
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
140

141 142 143 144 145 146
typedef struct
{
    HANDLE   handle;
    unsigned clock;
} vlc_cond_t;

147
typedef HANDLE  vlc_sem_t;
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
148 149 150 151 152 153 154 155 156 157 158

typedef struct
{
    vlc_mutex_t   mutex;
    vlc_cond_t    read_wait;
    vlc_cond_t    write_wait;
    unsigned long readers;
    unsigned long writers;
    DWORD         writer;
} vlc_rwlock_t;

159
typedef struct vlc_threadvar *vlc_threadvar_t;
160
typedef struct vlc_timer *vlc_timer_t;
161 162 163 164 165 166 167 168 169
#endif

#if defined( WIN32 ) && !defined ETIMEDOUT
#  define ETIMEDOUT 10060 /* This is the value in winsock.h. */
#endif

/*****************************************************************************
 * Function definitions
 *****************************************************************************/
170 171
VLC_EXPORT( void, vlc_mutex_init,    ( vlc_mutex_t * ) );
VLC_EXPORT( void, vlc_mutex_init_recursive, ( vlc_mutex_t * ) );
172 173
VLC_EXPORT( void, vlc_mutex_destroy, ( vlc_mutex_t * ) );
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 * ) );
178 179
VLC_EXPORT( void, vlc_cond_destroy,  ( vlc_cond_t * ) );
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 *) );
182 183 184 185 186 187
VLC_EXPORT( int,  vlc_cond_timedwait, (vlc_cond_t *, vlc_mutex_t *, mtime_t) );
VLC_EXPORT( void, vlc_sem_init, (vlc_sem_t *, unsigned) );
VLC_EXPORT( void, vlc_sem_destroy, (vlc_sem_t *) );
VLC_EXPORT( int,  vlc_sem_post, (vlc_sem_t *) );
VLC_EXPORT( void, vlc_sem_wait, (vlc_sem_t *) );

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
188 189 190 191 192
VLC_EXPORT( void, vlc_rwlock_init, (vlc_rwlock_t *) );
VLC_EXPORT( void, vlc_rwlock_destroy, (vlc_rwlock_t *) );
VLC_EXPORT( void, vlc_rwlock_rdlock, (vlc_rwlock_t *) );
VLC_EXPORT( void, vlc_rwlock_wrlock, (vlc_rwlock_t *) );
VLC_EXPORT( void, vlc_rwlock_unlock, (vlc_rwlock_t *) );
193 194
VLC_EXPORT( int, vlc_threadvar_create, (vlc_threadvar_t * , void (*) (void *) ) );
VLC_EXPORT( void, vlc_threadvar_delete, (vlc_threadvar_t *) );
195 196
VLC_EXPORT( int, vlc_threadvar_set, (vlc_threadvar_t, void *) );
VLC_EXPORT( void *, vlc_threadvar_get, (vlc_threadvar_t) );
197 198 199
VLC_EXPORT( int,  vlc_thread_create, ( vlc_object_t *, void * ( * ) ( vlc_object_t * ), int ) LIBVLC_USED LIBVLC_DEPRECATED );
VLC_EXPORT( int,  vlc_thread_set_priority, ( vlc_object_t *, int ) LIBVLC_DEPRECATED );
VLC_EXPORT( void, vlc_thread_join,   ( vlc_object_t * ) LIBVLC_DEPRECATED );
200

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 **) );
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
204 205
VLC_EXPORT (void, vlc_control_cancel, (int cmd, ...));

206
VLC_EXPORT( int, vlc_timer_create, (vlc_timer_t *, void (*) (void *), void *) LIBVLC_USED );
207 208 209
VLC_EXPORT( void, vlc_timer_destroy, (vlc_timer_t) );
VLC_EXPORT( void, vlc_timer_schedule, (vlc_timer_t, bool, mtime_t, mtime_t) );
VLC_EXPORT( unsigned, vlc_timer_getoverrun, (vlc_timer_t) LIBVLC_USED );
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
210

211
#ifndef LIBVLC_USE_PTHREAD_CANCEL
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
212
enum {
213 214
    VLC_CLEANUP_PUSH,
    VLC_CLEANUP_POP,
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
215 216
};
#endif
217

218 219 220
VLC_EXPORT( int, vlc_savecancel, (void) );
VLC_EXPORT( void, vlc_restorecancel, (int state) );
VLC_EXPORT( void, vlc_testcancel, (void) );
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
221

222
#if defined (LIBVLC_USE_PTHREAD_CANCEL)
223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257
/**
 * Registers a new procedure to run if the thread is cancelled (or otherwise
 * exits prematurely). Any call to vlc_cleanup_push() <b>must</b> paired with a
 * call to either vlc_cleanup_pop() or vlc_cleanup_run(). Branching into or out
 * of the block between these two function calls is not allowed (read: it will
 * likely crash the whole process). If multiple procedures are registered,
 * they are handled in last-in first-out order.
 *
 * @param routine procedure to call if the thread ends
 * @param arg argument for the procedure
 */
# define vlc_cleanup_push( routine, arg ) pthread_cleanup_push (routine, arg)

/**
 * Removes a cleanup procedure that was previously registered with
 * vlc_cleanup_push().
 */
# define vlc_cleanup_pop( ) pthread_cleanup_pop (0)

/**
 * Removes a cleanup procedure that was previously registered with
 * vlc_cleanup_push(), and executes it.
 */
# define vlc_cleanup_run( ) pthread_cleanup_pop (1)
#else
typedef struct vlc_cleanup_t vlc_cleanup_t;

struct vlc_cleanup_t
{
    vlc_cleanup_t *next;
    void         (*proc) (void *);
    void          *data;
};

/* 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
259 260 261 262 263 264 265 266 267 268 269 270 271 272 273
 * writing code that would break on POSIX (POSIX opens a block as well). */
# define vlc_cleanup_push( routine, arg ) \
    do { \
        vlc_cleanup_t vlc_cleanup_data = { NULL, routine, arg, }; \
        vlc_control_cancel (VLC_CLEANUP_PUSH, &vlc_cleanup_data)

# define vlc_cleanup_pop( ) \
        vlc_control_cancel (VLC_CLEANUP_POP); \
    } while (0)

# define vlc_cleanup_run( ) \
        vlc_control_cancel (VLC_CLEANUP_POP); \
        vlc_cleanup_data.proc (vlc_cleanup_data.data); \
    } while (0)

274
#endif /* LIBVLC_USE_PTHREAD_CANCEL */
275

276 277 278 279 280 281
static inline void vlc_cleanup_lock (void *lock)
{
    vlc_mutex_unlock ((vlc_mutex_t *)lock);
}
#define mutex_cleanup_push( lock ) vlc_cleanup_push (vlc_cleanup_lock, lock)

282 283 284 285 286 287
# if defined (_POSIX_SPIN_LOCKS) && ((_POSIX_SPIN_LOCKS - 0) > 0)
typedef pthread_spinlock_t vlc_spinlock_t;

/**
 * Initializes a spinlock.
 */
288
static inline void vlc_spin_init (vlc_spinlock_t *spin)
289
{
290 291
    if (pthread_spin_init (spin, PTHREAD_PROCESS_PRIVATE))
        abort ();
292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317
}

/**
 * Acquires a spinlock.
 */
static inline void vlc_spin_lock (vlc_spinlock_t *spin)
{
    pthread_spin_lock (spin);
}

/**
 * Releases a spinlock.
 */
static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
{
    pthread_spin_unlock (spin);
}

/**
 * Deinitializes a spinlock.
 */
static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
{
    pthread_spin_destroy (spin);
}

318
#elif defined (WIN32) && !defined (UNDER_CE)
319 320 321 322 323 324

typedef CRITICAL_SECTION vlc_spinlock_t;

/**
 * Initializes a spinlock.
 */
325
static inline void vlc_spin_init (vlc_spinlock_t *spin)
326
{
327 328
    if (!InitializeCriticalSectionAndSpinCount(spin, 4000))
        abort ();
329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359
}

/**
 * Acquires a spinlock.
 */
static inline void vlc_spin_lock (vlc_spinlock_t *spin)
{
    EnterCriticalSection(spin);
}

/**
 * Releases a spinlock.
 */
static inline void vlc_spin_unlock (vlc_spinlock_t *spin)
{
    LeaveCriticalSection(spin);
}

/**
 * Deinitializes a spinlock.
 */
static inline void vlc_spin_destroy (vlc_spinlock_t *spin)
{
    DeleteCriticalSection(spin);
}

#else

/* Fallback to plain mutexes if spinlocks are not available */
typedef vlc_mutex_t vlc_spinlock_t;

360
static inline void vlc_spin_init (vlc_spinlock_t *spin)
361
{
362
    vlc_mutex_init (spin);
363 364 365 366 367 368 369
}

# define vlc_spin_lock    vlc_mutex_lock
# define vlc_spin_unlock  vlc_mutex_unlock
# define vlc_spin_destroy vlc_mutex_destroy
#endif

370 371 372
/**
 * Issues a full memory barrier.
 */
373 374 375
#if defined (__APPLE__)
# include <libkern/OSAtomic.h> /* OSMemoryBarrier() */
#endif
376 377
static inline void barrier (void)
{
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
378
#if defined (__GNUC__) && !defined (__APPLE__) && \
379
            ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1))
380
    __sync_synchronize ();
381 382 383 384
#elif defined(__APPLE__)
    OSMemoryBarrier ();
#elif defined(__powerpc__)
    asm volatile ("sync":::"memory");
385
#elif 0 // defined(__i386__) /*  Requires SSE2 support */
386
    asm volatile ("mfence":::"memory");
387
#else
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
388
    vlc_spinlock_t spin;
389 390 391 392
    vlc_spin_init (&spin);
    vlc_spin_lock (&spin);
    vlc_spin_unlock (&spin);
    vlc_spin_destroy (&spin);
393 394 395
#endif
}

396 397
#define vlc_thread_create( P_THIS, FUNC, PRIORITY ) \
    vlc_thread_create( VLC_OBJECT(P_THIS), FUNC, PRIORITY )
398 399

#define vlc_thread_set_priority( P_THIS, PRIORITY )                         \
400
    vlc_thread_set_priority( VLC_OBJECT(P_THIS), PRIORITY )
401 402

#define vlc_thread_join( P_THIS )                                           \
403
    vlc_thread_join( VLC_OBJECT(P_THIS) )
404

405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427
#ifdef __cplusplus
/**
 * Helper C++ class to lock a mutex.
 * The mutex is locked when the object is created, and unlocked when the object
 * is destroyed.
 */
class vlc_mutex_locker
{
    private:
        vlc_mutex_t *lock;
    public:
        vlc_mutex_locker (vlc_mutex_t *m) : lock (m)
        {
            vlc_mutex_lock (lock);
        }

        ~vlc_mutex_locker (void)
        {
            vlc_mutex_unlock (lock);
        }
};
#endif

428 429 430
enum {
   VLC_AVCODEC_MUTEX = 0,
   VLC_GCRYPT_MUTEX,
431 432
   VLC_XLIB_MUTEX,
   /* Insert new entry HERE */
433 434 435 436 437 438 439
   VLC_MAX_MUTEX
};

VLC_EXPORT( void, vlc_global_mutex, ( unsigned, bool ) );
#define vlc_global_lock( n ) vlc_global_mutex( n, true )
#define vlc_global_unlock( n ) vlc_global_mutex( n, false )

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
440
#endif /* !_VLC_THREADS_H */