git.sesse.net Git - vlc/blob - src/control/event.c

   1 /*****************************************************************************
   2  * event.c: New libvlc event control API
   3  *****************************************************************************
   4  * Copyright (C) 2007 the VideoLAN team
   5  * $Id $
   6  *
   7  * Authors: Filippo Carone <filippo@carone.org>
   8  *          Pierre d'Herbemont <pdherbemont # videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 #include <vlc/libvlc.h>
  26
  27 #include "libvlc_internal.h"
  28 #include "event_internal.h"
  29
  30 typedef struct libvlc_event_listeners_group_t
  31 {
  32     libvlc_event_type_t event_type;
  33     vlc_array_t listeners;
  34     bool b_sublistener_removed;
  35 } libvlc_event_listeners_group_t;
  36
  37 /*
  38  * Private functions
  39  */
  40
  41 static bool
  42 group_contains_listener( libvlc_event_listeners_group_t * group,
  43                          libvlc_event_listener_t * searched_listener )
  44 {
  45     int i;
  46     for( i = 0; i < vlc_array_count(&group->listeners); i++ )
  47     {
  48         if( listeners_are_equal(searched_listener, vlc_array_item_at_index(&group->listeners, i)) )
  49             return true;
  50     }
  51     return false;
  52 }
  53
  54 /*
  55  * Internal libvlc functions
  56  */
  57
  58 /**************************************************************************
  59  *       libvlc_event_manager_new (internal) :
  60  *
  61  * Init an object's event manager.
  62  **************************************************************************/
  63 libvlc_event_manager_t *
  64 libvlc_event_manager_new( void * p_obj, libvlc_instance_t * p_libvlc_inst,
  65                            libvlc_exception_t *p_e )
  66 {
  67     libvlc_event_manager_t * p_em;
  68
  69     p_em = malloc(sizeof( libvlc_event_manager_t ));
  70     if( !p_em )
  71     {
  72         libvlc_exception_raise( p_e, "No Memory left" );
  73         return NULL;
  74     }
  75
  76     p_em->p_obj = p_obj;
  77     p_em->p_obj = p_obj;
  78     p_em->async_event_queue = NULL;
  79     p_em->p_libvlc_instance = p_libvlc_inst;
  80
  81     libvlc_retain( p_libvlc_inst );
  82     vlc_array_init( &p_em->listeners_groups );
  83     vlc_mutex_init( &p_em->object_lock );
  84     vlc_mutex_init_recursive( &p_em->event_sending_lock );
  85     return p_em;
  86 }
  87
  88 /**************************************************************************
  89  *       libvlc_event_manager_release (internal) :
  90  *
  91  * Init an object's event manager.
  92  **************************************************************************/
  93 void libvlc_event_manager_release( libvlc_event_manager_t * p_em )
  94 {
  95     libvlc_event_listeners_group_t * p_lg;
  96     int i,j ;
  97
  98     libvlc_event_async_fini(p_em);
  99
 100     vlc_mutex_destroy( &p_em->event_sending_lock );
 101     vlc_mutex_destroy( &p_em->object_lock );
 102
 103     for( i = 0; i < vlc_array_count(&p_em->listeners_groups); i++)
 104     {
 105         p_lg = vlc_array_item_at_index( &p_em->listeners_groups, i );
 106
 107         for( j = 0; j < vlc_array_count(&p_lg->listeners); j++)
 108             free( vlc_array_item_at_index( &p_lg->listeners, j ) );
 109
 110         vlc_array_clear( &p_lg->listeners );
 111         free( p_lg );
 112     }
 113     vlc_array_clear( &p_em->listeners_groups );
 114     libvlc_release( p_em->p_libvlc_instance );
 115     free( p_em );
 116 }
 117
 118 /**************************************************************************
 119  *       libvlc_event_manager_register_event_type (internal) :
 120  *
 121  * Init an object's event manager.
 122  **************************************************************************/
 123 void libvlc_event_manager_register_event_type(
 124         libvlc_event_manager_t * p_em,
 125         libvlc_event_type_t event_type,
 126         libvlc_exception_t * p_e )
 127 {
 128     libvlc_event_listeners_group_t * listeners_group;
 129     listeners_group = malloc(sizeof(libvlc_event_listeners_group_t));
 130     if( !listeners_group )
 131     {
 132         libvlc_exception_raise( p_e, "No Memory left" );
 133         return;
 134     }
 135
 136     listeners_group->event_type = event_type;
 137     vlc_array_init( &listeners_group->listeners );
 138
 139     vlc_mutex_lock( &p_em->object_lock );
 140     vlc_array_append( &p_em->listeners_groups, listeners_group );
 141     vlc_mutex_unlock( &p_em->object_lock );
 142 }
 143
 144 /**************************************************************************
 145  *       libvlc_event_send (internal) :
 146  *
 147  * Send a callback.
 148  **************************************************************************/
 149 void libvlc_event_send( libvlc_event_manager_t * p_em,
 150                         libvlc_event_t * p_event )
 151 {
 152     libvlc_event_listeners_group_t * listeners_group = NULL;
 153     libvlc_event_listener_t * listener_cached;
 154     libvlc_event_listener_t * listener;
 155     libvlc_event_listener_t * array_listeners_cached = NULL;
 156     int i, i_cached_listeners = 0;
 157
 158     /* Fill event with the sending object now */
 159     p_event->p_obj = p_em->p_obj;
 160
 161     /* Here a read/write lock would be nice */
 162
 163     vlc_mutex_lock( &p_em->object_lock );
 164     for( i = 0; i < vlc_array_count(&p_em->listeners_groups); i++)
 165     {
 166         listeners_group = vlc_array_item_at_index(&p_em->listeners_groups, i);
 167         if( listeners_group->event_type == p_event->type )
 168         {
 169             if( vlc_array_count( &listeners_group->listeners ) <= 0 )
 170                 break;
 171
 172             /* Cache a copy of the listener to avoid locking issues,
 173              * and allow that edition of listeners during callbacks will garantee immediate effect. */
 174             i_cached_listeners = vlc_array_count(&listeners_group->listeners);
 175             array_listeners_cached = malloc(sizeof(libvlc_event_listener_t)*(i_cached_listeners));
 176             if( !array_listeners_cached )
 177             {
 178                 vlc_mutex_unlock( &p_em->object_lock );
 179                 fprintf(stderr, "Can't alloc memory in libvlc_event_send" );
 180                 return;
 181             }
 182
 183             listener_cached = array_listeners_cached;
 184             for( i = 0; i < vlc_array_count(&listeners_group->listeners); i++)
 185             {
 186                 listener = vlc_array_item_at_index(&listeners_group->listeners, i);
 187                 memcpy( listener_cached, listener, sizeof(libvlc_event_listener_t) );
 188                 listener_cached++;
 189             }
 190             break;
 191         }
 192     }
 193
 194     if( !listeners_group )
 195     {
 196         free( array_listeners_cached );
 197         vlc_mutex_unlock( &p_em->object_lock );
 198         return;
 199     }
 200
 201     vlc_mutex_unlock( &p_em->object_lock );
 202
 203     vlc_mutex_lock( &p_em->event_sending_lock );
 204     listener_cached = array_listeners_cached;
 205     listeners_group->b_sublistener_removed = false;
 206     for( i = 0; i < i_cached_listeners; i++ )
 207     {
 208         if(listener_cached->is_asynchronous)
 209         {
 210             /* The listener wants not to block the emitter during event callback */
 211             libvlc_event_async_dispatch(p_em, listener_cached, p_event);
 212         }
 213         else
 214         {
 215             /* The listener wants to block the emitter during event callback */
 216
 217             listener_cached->pf_callback( p_event, listener_cached->p_user_data );
 218             listener_cached++;
 219
 220             if( listeners_group->b_sublistener_removed )
 221             {
 222                 /* If a callback was removed, this gets called */
 223                 bool valid_listener;
 224                 vlc_mutex_lock( &p_em->object_lock );
 225                 valid_listener = group_contains_listener( listeners_group, listener_cached );
 226                 vlc_mutex_unlock( &p_em->object_lock );
 227                 if( !valid_listener )
 228                 {
 229                     listener_cached++;
 230                     continue;
 231                 }
 232             }
 233         }
 234     }
 235     vlc_mutex_unlock( &p_em->event_sending_lock );
 236
 237     free( array_listeners_cached );
 238 }
 239
 240 /*
 241  * Public libvlc functions
 242  */
 243
 244 /**************************************************************************
 245  *       libvlc_event_type_name (public) :
 246  *
 247  * Get the char * name of an event type.
 248  **************************************************************************/
 249 static const char event_type_to_name[][35] =
 250 {
 251 #define EVENT(a) [a]=#a
 252     EVENT(libvlc_MediaMetaChanged),
 253     EVENT(libvlc_MediaSubItemAdded),
 254     EVENT(libvlc_MediaDurationChanged),
 255     EVENT(libvlc_MediaPreparsedChanged),
 256     EVENT(libvlc_MediaFreed),
 257     EVENT(libvlc_MediaStateChanged),
 258
 259     EVENT(libvlc_MediaPlayerNothingSpecial),
 260     EVENT(libvlc_MediaPlayerOpening),
 261     EVENT(libvlc_MediaPlayerBuffering),
 262     EVENT(libvlc_MediaPlayerPlaying),
 263     EVENT(libvlc_MediaPlayerPaused),
 264     EVENT(libvlc_MediaPlayerStopped),
 265     EVENT(libvlc_MediaPlayerForward),
 266     EVENT(libvlc_MediaPlayerBackward),
 267     EVENT(libvlc_MediaPlayerEndReached),
 268     EVENT(libvlc_MediaPlayerTimeChanged),
 269     EVENT(libvlc_MediaPlayerTitleChanged),
 270     EVENT(libvlc_MediaPlayerPositionChanged),
 271     EVENT(libvlc_MediaPlayerSeekableChanged),
 272     EVENT(libvlc_MediaPlayerPausableChanged),
 273
 274     EVENT(libvlc_MediaListItemAdded),
 275     EVENT(libvlc_MediaListWillAddItem),
 276     EVENT(libvlc_MediaListItemDeleted),
 277     EVENT(libvlc_MediaListWillDeleteItem),
 278
 279     EVENT(libvlc_MediaListViewItemAdded),
 280     EVENT(libvlc_MediaListViewWillAddItem),
 281     EVENT(libvlc_MediaListViewItemDeleted),
 282     EVENT(libvlc_MediaListViewWillDeleteItem),
 283
 284     EVENT(libvlc_MediaListPlayerPlayed),
 285     EVENT(libvlc_MediaListPlayerNextItemSet),
 286     EVENT(libvlc_MediaListPlayerStopped),
 287
 288     EVENT(libvlc_MediaDiscovererStarted),
 289     EVENT(libvlc_MediaDiscovererEnded),
 290
 291     EVENT(libvlc_MediaPlayerSnapshotTaken),
 292 #undef EVENT
 293 };
 294
 295 static const char unkwown_event_name[] = "Unknown Event";
 296
 297 const char * libvlc_event_type_name( libvlc_event_type_t event_type )
 298 {
 299     if( event_type >= sizeof(event_type_to_name)/sizeof(event_type_to_name[0]))
 300         return unkwown_event_name;
 301     return event_type_to_name[event_type];
 302 }
 303
 304 /**************************************************************************
 305  *       event_attach (internal) :
 306  *
 307  * Add a callback for an event.
 308  **************************************************************************/
 309 static
 310 void event_attach( libvlc_event_manager_t * p_event_manager,
 311                          libvlc_event_type_t event_type,
 312                          libvlc_callback_t pf_callback,
 313                          void *p_user_data,
 314                          bool is_asynchronous,
 315                          libvlc_exception_t *p_e )
 316 {
 317     libvlc_event_listeners_group_t * listeners_group;
 318     libvlc_event_listener_t * listener;
 319     int i;
 320
 321     listener = malloc(sizeof(libvlc_event_listener_t));
 322     if( !listener )
 323     {
 324         libvlc_exception_raise( p_e, "No Memory left" );
 325         return;
 326     }
 327
 328     listener->event_type = event_type;
 329     listener->p_user_data = p_user_data;
 330     listener->pf_callback = pf_callback;
 331     listener->is_asynchronous = is_asynchronous;
 332
 333     vlc_mutex_lock( &p_event_manager->object_lock );
 334     for( i = 0; i < vlc_array_count(&p_event_manager->listeners_groups); i++ )
 335     {
 336         listeners_group = vlc_array_item_at_index(&p_event_manager->listeners_groups, i);
 337         if( listeners_group->event_type == listener->event_type )
 338         {
 339             vlc_array_append( &listeners_group->listeners, listener );
 340             vlc_mutex_unlock( &p_event_manager->object_lock );
 341             return;
 342         }
 343     }
 344     vlc_mutex_unlock( &p_event_manager->object_lock );
 345
 346     free(listener);
 347     libvlc_exception_raise( p_e,
 348                            "This object event manager doesn't know about '%s' events",
 349                            libvlc_event_type_name(event_type));
 350 }
 351
 352 /**************************************************************************
 353  *       libvlc_event_attach (public) :
 354  *
 355  * Add a callback for an event.
 356  **************************************************************************/
 357 void libvlc_event_attach( libvlc_event_manager_t * p_event_manager,
 358                          libvlc_event_type_t event_type,
 359                          libvlc_callback_t pf_callback,
 360                          void *p_user_data,
 361                          libvlc_exception_t *p_e )
 362 {
 363     event_attach(p_event_manager, event_type, pf_callback, p_user_data, false /* synchronous */, p_e);
 364 }
 365
 366 /**************************************************************************
 367  *       libvlc_event_attach (public) :
 368  *
 369  * Add a callback for an event.
 370  **************************************************************************/
 371 void libvlc_event_attach_async( libvlc_event_manager_t * p_event_manager,
 372                          libvlc_event_type_t event_type,
 373                          libvlc_callback_t pf_callback,
 374                          void *p_user_data,
 375                          libvlc_exception_t *p_e )
 376 {
 377     event_attach(p_event_manager, event_type, pf_callback, p_user_data, true /* asynchronous */, p_e);
 378 }
 379
 380 /**************************************************************************
 381  *       libvlc_event_detach (public) :
 382  *
 383  * Remove a callback for an event.
 384  **************************************************************************/
 385 void libvlc_event_detach( libvlc_event_manager_t *p_event_manager,
 386                                      libvlc_event_type_t event_type,
 387                                      libvlc_callback_t pf_callback,
 388                                      void *p_user_data,
 389                                      libvlc_exception_t *p_e )
 390 {
 391     libvlc_event_listeners_group_t * listeners_group;
 392     libvlc_event_listener_t * listener;
 393     int i, j;
 394     bool found = false;
 395
 396     vlc_mutex_lock( &p_event_manager->event_sending_lock );
 397     vlc_mutex_lock( &p_event_manager->object_lock );
 398     for( i = 0; i < vlc_array_count(&p_event_manager->listeners_groups); i++)
 399     {
 400         listeners_group = vlc_array_item_at_index(&p_event_manager->listeners_groups, i);
 401         if( listeners_group->event_type == event_type )
 402         {
 403             for( j = 0; j < vlc_array_count(&listeners_group->listeners); j++)
 404             {
 405                 listener = vlc_array_item_at_index(&listeners_group->listeners, j);
 406                 if( listener->event_type == event_type &&
 407                     listener->pf_callback == pf_callback &&
 408                     listener->p_user_data == p_user_data )
 409                 {
 410                     /* that's our listener */
 411
 412                     /* Mark this group as edited so that libvlc_event_send
 413                      * will recheck what listener to call */
 414                     listeners_group->b_sublistener_removed = false;
 415
 416                     free( listener );
 417                     vlc_array_remove( &listeners_group->listeners, j );
 418                     found = true;
 419                     break;
 420                 }
 421             }
 422         }
 423     }
 424     vlc_mutex_unlock( &p_event_manager->object_lock );
 425     vlc_mutex_unlock( &p_event_manager->event_sending_lock );
 426
 427     /* Now make sure any pending async event won't get fired after that point */
 428     libvlc_event_listener_t listener_to_remove;
 429     listener_to_remove.event_type  = event_type;
 430     listener_to_remove.pf_callback = pf_callback;
 431     listener_to_remove.p_user_data = p_user_data;
 432     listener_to_remove.is_asynchronous = true;
 433
 434     libvlc_event_async_ensure_listener_removal(p_event_manager, &listener_to_remove);
 435
 436     if(!found)
 437     {
 438         libvlc_exception_raise( p_e,
 439                                "This object event manager doesn't know about '%s,%p,%p' event observer",
 440                                libvlc_event_type_name(event_type), pf_callback, p_user_data );
 441     }
 442 }