git.sesse.net Git - vlc/blob - include/vlc_threads.h

   1 /*****************************************************************************
   2  * threads.h : threads implementation for the VideoLAN client
   3  * This header provides a portable threads implementation.
   4  *****************************************************************************
   5  * Copyright (C) 1999, 2000 VideoLAN
   6  * $Id: vlc_threads.h,v 1.2 2002/06/02 13:38:03 gbazin Exp $
   7  *
   8  * Authors: Jean-Marc Dressler <polux@via.ecp.fr>
   9  *          Samuel Hocevar <sam@via.ecp.fr>
  10  *          Gildas Bazin <gbazin@netcourrier.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  25  *****************************************************************************/
  26
  27 #include <stdio.h>
  28
  29 #if defined(GPROF) || defined(DEBUG)
  30 #   include <sys/time.h>
  31 #endif
  32
  33 #if defined( PTH_INIT_IN_PTH_H )                                  /* GNU Pth */
  34 #   include <pth.h>
  35
  36 #elif defined( ST_INIT_IN_ST_H )                            /* State threads */
  37 #   include <st.h>
  38
  39 #elif defined( WIN32 )                                          /* Win32 API */
  40 #   include <process.h>
  41
  42 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )  /* pthreads (like Linux & BSD) */
  43 #   include <pthread.h>
  44 #   ifdef DEBUG
  45         /* Needed for pthread_cond_timedwait */
  46 #       include <errno.h>
  47 #   endif
  48     /* This is not prototyped under Linux, though it exists. */
  49     int pthread_mutexattr_setkind_np( pthread_mutexattr_t *attr, int kind );
  50
  51 #elif defined( HAVE_CTHREADS_H )                                  /* GNUMach */
  52 #   include <cthreads.h>
  53
  54 #elif defined( HAVE_KERNEL_SCHEDULER_H )                             /* BeOS */
  55 #   include <kernel/OS.h>
  56 #   include <kernel/scheduler.h>
  57 #   include <byteorder.h>
  58
  59 #else
  60 #   error no threads available on your system !
  61
  62 #endif
  63
  64 /*****************************************************************************
  65  * Constants
  66  *****************************************************************************
  67  * These constants are used by all threads in *_CreateThread() and
  68  * *_DestroyThreads() functions. Since those calls are non-blocking, an integer
  69  * value is used as a shared flag to represent the status of the thread.
  70  *****************************************************************************/
  71
  72 /* Void status - this value can be used to make sure no operation is currently
  73  * in progress on the concerned thread in an array of recorded threads */
  74 #define THREAD_NOP          0                            /* nothing happened */
  75
  76 /* Creation status */
  77 #define THREAD_CREATE       10                     /* thread is initializing */
  78 #define THREAD_START        11                          /* thread has forked */
  79 #define THREAD_READY        19                            /* thread is ready */
  80
  81 /* Destructions status */
  82 #define THREAD_DESTROY      20            /* destruction order has been sent */
  83 #define THREAD_END          21        /* destruction order has been received */
  84 #define THREAD_OVER         29             /* thread does not exist any more */
  85
  86 /* Error status */
  87 #define THREAD_ERROR        30                           /* an error occured */
  88 #define THREAD_FATAL        31  /* an fatal error occured - program must end */
  89
  90 /*****************************************************************************
  91  * Type definitions
  92  *****************************************************************************/
  93
  94 #if defined( PTH_INIT_IN_PTH_H )
  95 typedef pth_t            vlc_thread_t;
  96 typedef pth_mutex_t      vlc_mutex_t;
  97 typedef pth_cond_t       vlc_cond_t;
  98
  99 #elif defined( ST_INIT_IN_ST_H )
 100 typedef st_thread_t *    vlc_thread_t;
 101 typedef st_mutex_t *     vlc_mutex_t;
 102 typedef st_cond_t *      vlc_cond_t;
 103
 104 #elif defined( WIN32 )
 105 typedef HANDLE vlc_thread_t;
 106 typedef BOOL (WINAPI *SIGNALOBJECTANDWAIT) ( HANDLE, HANDLE, DWORD, BOOL );
 107 typedef unsigned (__stdcall *PTHREAD_START) (void *);
 108
 109 typedef struct
 110 {
 111     CRITICAL_SECTION    csection;
 112     HANDLE              mutex;
 113     SIGNALOBJECTANDWAIT SignalObjectAndWait;
 114 } vlc_mutex_t;
 115
 116 typedef struct
 117 {
 118     int             i_waiting_threads;
 119     HANDLE          signal;
 120 } vlc_cond_t;
 121
 122 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
 123 typedef pthread_t        vlc_thread_t;
 124 typedef pthread_mutex_t  vlc_mutex_t;
 125 typedef pthread_cond_t   vlc_cond_t;
 126
 127 #elif defined( HAVE_CTHREADS_H )
 128 typedef cthread_t        vlc_thread_t;
 129
 130 /* Those structs are the ones defined in /include/cthreads.h but we need
 131  * to handle (&foo) where foo is a (mutex_t) while they handle (foo) where
 132  * foo is a (mutex_t*) */
 133 typedef struct
 134 {
 135     spin_lock_t held;
 136     spin_lock_t lock;
 137     char *name;
 138     struct cthread_queue queue;
 139 } vlc_mutex_t;
 140
 141 typedef struct
 142 {
 143     spin_lock_t lock;
 144     struct cthread_queue queue;
 145     char *name;
 146     struct cond_imp *implications;
 147 } vlc_cond_t;
 148
 149 #elif defined( HAVE_KERNEL_SCHEDULER_H )
 150 /* This is the BeOS implementation of the vlc threads, note that the mutex is
 151  * not a real mutex and the cond_var is not like a pthread cond_var but it is
 152  * enough for what wee need */
 153
 154 typedef thread_id vlc_thread_t;
 155
 156 typedef struct
 157 {
 158     int32           init;
 159     sem_id          lock;
 160 } vlc_mutex_t;
 161
 162 typedef struct
 163 {
 164     int32           init;
 165     thread_id       thread;
 166 } vlc_cond_t;
 167
 168 #endif
 169
 170 /*****************************************************************************
 171  * Function definitions
 172  *****************************************************************************/
 173 VLC_EXPORT( int,  __vlc_threads_init,  ( vlc_object_t * ) );
 174 VLC_EXPORT( int,    vlc_threads_end,   ( void ) );
 175 VLC_EXPORT( int,  __vlc_mutex_init,    ( vlc_object_t *, vlc_mutex_t * ) );
 176 VLC_EXPORT( int,  __vlc_mutex_destroy, ( char *, int, vlc_mutex_t * ) );
 177 VLC_EXPORT( int,    vlc_cond_init,     ( vlc_cond_t * ) );
 178 VLC_EXPORT( int,  __vlc_cond_destroy,  ( char *, int, vlc_cond_t * ) );
 179 VLC_EXPORT( int,  __vlc_thread_create, ( vlc_object_t *, char *, int, char *, void * ( * ) ( void * ), vlc_bool_t ) );
 180 VLC_EXPORT( void, __vlc_thread_ready,  ( vlc_object_t * ) );
 181 VLC_EXPORT( void, __vlc_thread_join,   ( vlc_object_t *, char *, int ) );
 182
 183 /*****************************************************************************
 184  * vlc_threads_init: initialize threads system
 185  *****************************************************************************/
 186 #define vlc_threads_init( P_THIS )                                          \
 187     __vlc_threads_init( CAST_TO_VLC_OBJECT(P_THIS) )
 188
 189 /*****************************************************************************
 190  * vlc_mutex_init: initialize a mutex
 191  *****************************************************************************/
 192 #define vlc_mutex_init( P_THIS, P_MUTEX )                                   \
 193     __vlc_mutex_init( CAST_TO_VLC_OBJECT(P_THIS), P_MUTEX )
 194
 195 /*****************************************************************************
 196  * vlc_mutex_lock: lock a mutex
 197  *****************************************************************************/
 198 #ifdef DEBUG
 199 #   define vlc_mutex_lock( P_MUTEX )                                        \
 200         __vlc_mutex_lock( __FILE__, __LINE__, P_MUTEX )
 201 #else
 202 #   define vlc_mutex_lock( P_MUTEX )                                        \
 203         __vlc_mutex_lock( "(unknown)", 0, P_MUTEX )
 204 #endif
 205
 206 static inline int __vlc_mutex_lock( char * psz_file, int i_line,
 207                                     vlc_mutex_t *p_mutex )
 208 {
 209 #if defined( PTH_INIT_IN_PTH_H )
 210     return pth_mutex_acquire( p_mutex, TRUE, NULL );
 211
 212 #elif defined( ST_INIT_IN_ST_H )
 213     return st_mutex_lock( *p_mutex );
 214
 215 #elif defined( WIN32 )
 216     if( p_mutex->mutex )
 217     {
 218         WaitForSingleObject( p_mutex->mutex, INFINITE );
 219     }
 220     else
 221     {
 222         EnterCriticalSection( &p_mutex->csection );
 223     }
 224     return 0;
 225
 226 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
 227     int i_return = pthread_mutex_lock( p_mutex );
 228     if( i_return )
 229     {
 230 //        msg_Err( "thread %d: mutex_lock failed at %s:%d (%s)",
 231 //                 pthread_self(), psz_file, i_line, strerror(i_return) );
 232     }
 233     return i_return;
 234
 235 #elif defined( HAVE_CTHREADS_H )
 236     mutex_lock( p_mutex );
 237     return 0;
 238
 239 #elif defined( HAVE_KERNEL_SCHEDULER_H )
 240     status_t err;
 241
 242     if( !p_mutex )
 243     {
 244         return B_BAD_VALUE;
 245     }
 246
 247     if( p_mutex->init < 2000 )
 248     {
 249         return B_NO_INIT;
 250     }
 251
 252     err = acquire_sem( p_mutex->lock );
 253     return err;
 254
 255 #endif
 256 }
 257
 258 /*****************************************************************************
 259  * vlc_mutex_unlock: unlock a mutex
 260  *****************************************************************************/
 261 #ifdef DEBUG
 262 #   define vlc_mutex_unlock( P_MUTEX )                                      \
 263         __vlc_mutex_unlock( __FILE__, __LINE__, P_MUTEX )
 264 #else
 265 #   define vlc_mutex_unlock( P_MUTEX )                                      \
 266         __vlc_mutex_unlock( "(unknown)", 0, P_MUTEX )
 267 #endif
 268
 269 static inline int __vlc_mutex_unlock( char * psz_file, int i_line,
 270                                       vlc_mutex_t *p_mutex )
 271 {
 272 #if defined( PTH_INIT_IN_PTH_H )
 273     return pth_mutex_release( p_mutex );
 274
 275 #elif defined( ST_INIT_IN_ST_H )
 276     return st_mutex_unlock( *p_mutex );
 277
 278 #elif defined( WIN32 )
 279     if( p_mutex->mutex )
 280     {
 281         ReleaseMutex( p_mutex->mutex );
 282     }
 283     else
 284     {
 285         LeaveCriticalSection( &p_mutex->csection );
 286     }
 287     return 0;
 288
 289 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
 290     int i_return = pthread_mutex_unlock( p_mutex );
 291     if( i_return )
 292     {
 293 //        msg_Err( "thread %d: mutex_unlock failed at %s:%d (%s)",
 294 //                 pthread_self(), psz_file, i_line, strerror(i_return) );
 295     }
 296     return i_return;
 297
 298 #elif defined( HAVE_CTHREADS_H )
 299     mutex_unlock( p_mutex );
 300     return 0;
 301
 302 #elif defined( HAVE_KERNEL_SCHEDULER_H )
 303     if( !p_mutex)
 304     {
 305         return B_BAD_VALUE;
 306     }
 307
 308     if( p_mutex->init < 2000 )
 309     {
 310         return B_NO_INIT;
 311     }
 312
 313     release_sem( p_mutex->lock );
 314     return B_OK;
 315
 316 #endif
 317 }
 318
 319 /*****************************************************************************
 320  * vlc_mutex_destroy: destroy a mutex
 321  *****************************************************************************/
 322 #ifdef DEBUG
 323 #   define vlc_mutex_destroy( P_MUTEX )                                     \
 324         __vlc_mutex_destroy( __FILE__, __LINE__, P_MUTEX )
 325 #else
 326 #   define vlc_mutex_destroy( P_MUTEX )                                     \
 327         __vlc_mutex_destroy( "(unknown)", 0, P_MUTEX )
 328 #endif
 329
 330 /*****************************************************************************
 331  * vlc_cond_signal: start a thread on condition completion
 332  *****************************************************************************/
 333 static inline int vlc_cond_signal( vlc_cond_t *p_condvar )
 334 {
 335 #if defined( PTH_INIT_IN_PTH_H )
 336     return pth_cond_notify( p_condvar, FALSE );
 337
 338 #elif defined( ST_INIT_IN_ST_H )
 339     return st_cond_signal( *p_condvar );
 340
 341 #elif defined( WIN32 )
 342     /* Release one waiting thread if one is available. */
 343     /* For this trick to work properly, the vlc_cond_signal must be surrounded
 344      * by a mutex. This will prevent another thread from stealing the signal */
 345     PulseEvent( p_condvar->signal );
 346     return 0;
 347
 348 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
 349     return pthread_cond_signal( p_condvar );
 350
 351 #elif defined( HAVE_CTHREADS_H )
 352     /* condition_signal() */
 353     if ( p_condvar->queue.head || p_condvar->implications )
 354     {
 355         cond_signal( (condition_t)p_condvar );
 356     }
 357     return 0;
 358
 359 #elif defined( HAVE_KERNEL_SCHEDULER_H )
 360     if( !p_condvar )
 361     {
 362         return B_BAD_VALUE;
 363     }
 364
 365     if( p_condvar->init < 2000 )
 366     {
 367         return B_NO_INIT;
 368     }
 369
 370     while( p_condvar->thread != -1 )
 371     {
 372         thread_info info;
 373         if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE )
 374         {
 375             return 0;
 376         }
 377
 378         if( info.state != B_THREAD_SUSPENDED )
 379         {
 380             /* The  waiting thread is not suspended so it could
 381              * have been interrupted beetwen the unlock and the
 382              * suspend_thread line. That is why we sleep a little
 383              * before retesting p_condver->thread. */
 384             snooze( 10000 );
 385         }
 386         else
 387         {
 388             /* Ok, we have to wake up that thread */
 389             resume_thread( p_condvar->thread );
 390             return 0;
 391         }
 392     }
 393     return 0;
 394
 395 #endif
 396 }
 397
 398 /*****************************************************************************
 399  * vlc_cond_broadcast: start all threads waiting on condition completion
 400  *****************************************************************************/
 401 /*
 402  * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
 403  * Only works with pthreads, you need to adapt it for others
 404  * FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
 405  */
 406 static inline int vlc_cond_broadcast( vlc_cond_t *p_condvar )
 407 {
 408 #if defined( PTH_INIT_IN_PTH_H )
 409     return pth_cond_notify( p_condvar, FALSE );
 410
 411 #elif defined( ST_INIT_IN_ST_H )
 412     return st_cond_broadcast( p_condvar );
 413
 414 #elif defined( WIN32 )
 415     /* Release all waiting threads. */
 416     while( p_condvar->i_waiting_threads )
 417     {
 418         PulseEvent( p_condvar->signal );
 419         Sleep( 1 ); /* deschedule the current thread */
 420     }
 421     return 0;
 422
 423 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
 424     return pthread_cond_broadcast( p_condvar );
 425
 426 #elif defined( HAVE_CTHREADS_H )
 427     /* condition_signal() */
 428     if ( p_condvar->queue.head || p_condvar->implications )
 429     {
 430         cond_signal( (condition_t)p_condvar );
 431     }
 432     return 0;
 433
 434 #elif defined( HAVE_KERNEL_SCHEDULER_H )
 435     if( !p_condvar )
 436     {
 437         return B_BAD_VALUE;
 438     }
 439
 440     if( p_condvar->init < 2000 )
 441     {
 442         return B_NO_INIT;
 443     }
 444
 445     while( p_condvar->thread != -1 )
 446     {
 447         thread_info info;
 448         if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE )
 449         {
 450             return 0;
 451         }
 452
 453         if( info.state != B_THREAD_SUSPENDED )
 454         {
 455             /* The  waiting thread is not suspended so it could
 456              * have been interrupted beetwen the unlock and the
 457              * suspend_thread line. That is why we sleep a little
 458              * before retesting p_condver->thread. */
 459             snooze( 10000 );
 460         }
 461         else
 462         {
 463             /* Ok, we have to wake up that thread */
 464             resume_thread( p_condvar->thread );
 465             return 0;
 466         }
 467     }
 468     return 0;
 469
 470 #endif
 471 }
 472
 473 /*****************************************************************************
 474  * vlc_cond_wait: wait until condition completion
 475  *****************************************************************************/
 476 #ifdef DEBUG
 477 #   define vlc_cond_wait( P_COND, P_MUTEX )                                   \
 478         __vlc_cond_wait( __FILE__, __LINE__, P_COND, P_MUTEX  )
 479 #else
 480 #   define vlc_cond_wait( P_COND, P_MUTEX )                                   \
 481         __vlc_cond_wait( "(unknown)", 0, P_COND, P_MUTEX )
 482 #endif
 483
 484 static inline int __vlc_cond_wait( char * psz_file, int i_line,
 485                                    vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex )
 486 {
 487 #if defined( PTH_INIT_IN_PTH_H )
 488     return pth_cond_await( p_condvar, p_mutex, NULL );
 489
 490 #elif defined( ST_INIT_IN_ST_H )
 491     int i_ret;
 492
 493     st_mutex_unlock( *p_mutex );
 494     i_ret = st_cond_wait( *p_condvar );
 495     st_mutex_lock( *p_mutex );
 496
 497     return i_ret;
 498
 499 #elif defined( WIN32 )
 500     /* It is only possible to atomically release the mutex and initiate the
 501      * waiting on WinNT/2K/XP. Win9x doesn't have SignalObjectAndWait().
 502      */
 503     int i_result;
 504
 505     p_condvar->i_waiting_threads ++;
 506
 507     if( p_mutex->mutex )
 508     {
 509         p_mutex->SignalObjectAndWait( p_mutex->mutex, p_condvar->signal,
 510                                       INFINITE, FALSE );
 511     }
 512     else
 513     {
 514         /* Release the mutex */
 515         vlc_mutex_unlock( p_mutex );
 516         i_result = WaitForSingleObject( p_condvar->signal, INFINITE);
 517         p_condvar->i_waiting_threads --;
 518     }
 519
 520     /* Reacquire the mutex before returning. */
 521     vlc_mutex_lock( p_mutex );
 522
 523     return( i_result == WAIT_FAILED );
 524
 525 #elif defined( PTHREAD_COND_T_IN_PTHREAD_H )
 526
 527 #   ifdef DEBUG
 528     /* In debug mode, timeout */
 529     struct timeval now;
 530     struct timespec timeout;
 531     int    i_result;
 532
 533     for( ; ; )
 534     {
 535         gettimeofday( &now, NULL );
 536         timeout.tv_sec = now.tv_sec + THREAD_COND_TIMEOUT;
 537         timeout.tv_nsec = now.tv_usec * 1000;
 538
 539         i_result = pthread_cond_timedwait( p_condvar, p_mutex, &timeout );
 540
 541         if( i_result == ETIMEDOUT )
 542         {
 543 //X            msg_Warn( "thread %d: possible deadlock detected "
 544 //X                      "in cond_wait at %s:%d (%s)", pthread_self(),
 545 //X                      psz_file, i_line, strerror(i_result) );
 546             continue;
 547         }
 548
 549         if( i_result )
 550         {
 551 //X            msg_Err( "thread %d: cond_wait failed at %s:%d (%s)",
 552 //X                     pthread_self(), psz_file, i_line, strerror(i_result) );
 553         }
 554         return( i_result );
 555     }
 556 #   else
 557     return pthread_cond_wait( p_condvar, p_mutex );
 558 #   endif
 559
 560 #elif defined( HAVE_CTHREADS_H )
 561     condition_wait( (condition_t)p_condvar, (mutex_t)p_mutex );
 562     return 0;
 563
 564 #elif defined( HAVE_KERNEL_SCHEDULER_H )
 565     if( !p_condvar )
 566     {
 567         return B_BAD_VALUE;
 568     }
 569
 570     if( !p_mutex )
 571     {
 572         return B_BAD_VALUE;
 573     }
 574
 575     if( p_condvar->init < 2000 )
 576     {
 577         return B_NO_INIT;
 578     }
 579
 580     /* The p_condvar->thread var is initialized before the unlock because
 581      * it enables to identify when the thread is interrupted beetwen the
 582      * unlock line and the suspend_thread line */
 583     p_condvar->thread = find_thread( NULL );
 584     vlc_mutex_unlock( p_mutex );
 585     suspend_thread( p_condvar->thread );
 586     p_condvar->thread = -1;
 587
 588     vlc_mutex_lock( p_mutex );
 589     return 0;
 590
 591 #endif
 592 }
 593
 594 /*****************************************************************************
 595  * vlc_cond_destroy: destroy a condition
 596  *****************************************************************************/
 597 #ifdef DEBUG
 598 #   define vlc_cond_destroy( P_COND )                                       \
 599         __vlc_cond_destroy( __FILE__, __LINE__, P_COND )
 600 #else
 601 #   define vlc_cond_destroy( P_COND )                                       \
 602         __vlc_cond_destroy( "(unknown)", 0, P_COND )
 603 #endif
 604
 605 /*****************************************************************************
 606  * vlc_thread_create: create a thread
 607  *****************************************************************************/
 608 #   define vlc_thread_create( P_THIS, PSZ_NAME, FUNC, WAIT )                \
 609         __vlc_thread_create( CAST_TO_VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, (void * ( * ) ( void * ))FUNC, WAIT )
 610
 611 /*****************************************************************************
 612  * vlc_thread_ready: tell the parent thread we were successfully spawned
 613  *****************************************************************************/
 614 #   define vlc_thread_ready( P_THIS )                                       \
 615         __vlc_thread_ready( CAST_TO_VLC_OBJECT(P_THIS) )
 616
 617 /*****************************************************************************
 618  * vlc_thread_join: wait until a thread exits
 619  *****************************************************************************/
 620 #ifdef DEBUG
 621 #   define vlc_thread_join( P_THIS )                                        \
 622         __vlc_thread_join( CAST_TO_VLC_OBJECT(P_THIS), __FILE__, __LINE__ )
 623 #else
 624 #   define vlc_thread_join( P_THIS )                                        \
 625         __vlc_thread_join( CAST_TO_VLC_OBJECT(P_THIS), "(unknown)", 0 )
 626 #endif