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 #ifdef HAVE_CONFIG_H
  26 # include "config.h"
  27 #endif
  28
  29 #include <vlc/libvlc.h>
  30
  31 #include "libvlc_internal.h"
  32 #include "event_internal.h"
  33
  34 typedef struct libvlc_event_listeners_group_t
  35 {
  36     libvlc_event_type_t event_type;
  37     vlc_array_t listeners;
  38     bool b_sublistener_removed;
  39 } libvlc_event_listeners_group_t;
  40
  41 /*
  42  * Private functions
  43  */
  44
  45 static bool
  46 group_contains_listener( libvlc_event_listeners_group_t * group,
  47                          libvlc_event_listener_t * searched_listener )
  48 {
  49     int i;
  50     for( i = 0; i < vlc_array_count(&group->listeners); i++ )
  51     {
  52         if( listeners_are_equal(searched_listener, vlc_array_item_at_index(&group->listeners, i)) )
  53             return true;
  54     }
  55     return false;
  56 }
  57
  58 /*
  59  * Internal libvlc functions
  60  */
  61
  62 /**************************************************************************
  63  *       libvlc_event_manager_new (internal) :
  64  *
  65  * Init an object's event manager.
  66  **************************************************************************/
  67 libvlc_event_manager_t *
  68 libvlc_event_manager_new( void * p_obj, libvlc_instance_t * p_libvlc_inst,
  69                            libvlc_exception_t *p_e )
  70 {
  71     libvlc_event_manager_t * p_em;
  72
  73     p_em = malloc(sizeof( libvlc_event_manager_t ));
  74     if( !p_em )
  75     {
  76         libvlc_exception_raise( p_e, "No Memory left" );
  77         return NULL;
  78     }
  79
  80     p_em->p_obj = p_obj;
  81     p_em->p_obj = p_obj;
  82     p_em->async_event_queue = NULL;
  83     p_em->p_libvlc_instance = p_libvlc_inst;
  84
  85     libvlc_retain( p_libvlc_inst );
  86     vlc_array_init( &p_em->listeners_groups );
  87     vlc_mutex_init( &p_em->object_lock );
  88     vlc_mutex_init_recursive( &p_em->event_sending_lock );
  89     return p_em;
  90 }
  91
  92 /**************************************************************************
  93  *       libvlc_event_manager_release (internal) :
  94  *
  95  * Release an object's event manager.
  96  **************************************************************************/
  97 void libvlc_event_manager_release( libvlc_event_manager_t * p_em )
  98 {
  99     libvlc_event_listeners_group_t * p_lg;
 100     int i,j ;
 101
 102     libvlc_event_async_fini(p_em);
 103
 104     vlc_mutex_destroy( &p_em->event_sending_lock );
 105     vlc_mutex_destroy( &p_em->object_lock );
 106
 107     for( i = 0; i < vlc_array_count(&p_em->listeners_groups); i++)
 108     {
 109         p_lg = vlc_array_item_at_index( &p_em->listeners_groups, i );
 110
 111         for( j = 0; j < vlc_array_count(&p_lg->listeners); j++)
 112             free( vlc_array_item_at_index( &p_lg->listeners, j ) );
 113
 114         vlc_array_clear( &p_lg->listeners );
 115         free( p_lg );
 116     }
 117     vlc_array_clear( &p_em->listeners_groups );
 118     libvlc_release( p_em->p_libvlc_instance );
 119     free( p_em );
 120 }
 121
 122 /**************************************************************************
 123  *       libvlc_event_manager_register_event_type (internal) :
 124  *
 125  * Init an object's event manager.
 126  **************************************************************************/
 127 void libvlc_event_manager_register_event_type(
 128         libvlc_event_manager_t * p_em,
 129         libvlc_event_type_t event_type,
 130         libvlc_exception_t * p_e )
 131 {
 132     libvlc_event_listeners_group_t * listeners_group;
 133     listeners_group = malloc(sizeof(libvlc_event_listeners_group_t));
 134     if( !listeners_group )
 135     {
 136         libvlc_exception_raise( p_e, "No Memory left" );
 137         return;
 138     }
 139
 140     listeners_group->event_type = event_type;
 141     vlc_array_init( &listeners_group->listeners );
 142
 143     vlc_mutex_lock( &p_em->object_lock );
 144     vlc_array_append( &p_em->listeners_groups, listeners_group );
 145     vlc_mutex_unlock( &p_em->object_lock );
 146 }
 147
 148 /**************************************************************************
 149  *       libvlc_event_send (internal) :
 150  *
 151  * Send a callback.
 152  **************************************************************************/
 153 void libvlc_event_send( libvlc_event_manager_t * p_em,
 154                         libvlc_event_t * p_event )
 155 {
 156     libvlc_event_listeners_group_t * listeners_group = NULL;
 157     libvlc_event_listener_t * listener_cached;
 158     libvlc_event_listener_t * listener;
 159     libvlc_event_listener_t * array_listeners_cached = NULL;
 160     int i, i_cached_listeners = 0;
 161
 162     /* Fill event with the sending object now */
 163     p_event->p_obj = p_em->p_obj;
 164
 165     /* Here a read/write lock would be nice */
 166
 167     vlc_mutex_lock( &p_em->object_lock );
 168     for( i = 0; i < vlc_array_count(&p_em->listeners_groups); i++)
 169     {
 170         listeners_group = vlc_array_item_at_index(&p_em->listeners_groups, i);
 171         if( listeners_group->event_type == p_event->type )
 172         {
 173             if( vlc_array_count( &listeners_group->listeners ) <= 0 )
 174                 break;
 175
 176             /* Cache a copy of the listener to avoid locking issues,
 177              * and allow that edition of listeners during callbacks will garantee immediate effect. */
 178             i_cached_listeners = vlc_array_count(&listeners_group->listeners);
 179             array_listeners_cached = malloc(sizeof(libvlc_event_listener_t)*(i_cached_listeners));
 180             if( !array_listeners_cached )
 181             {
 182                 vlc_mutex_unlock( &p_em->object_lock );
 183                 fprintf(stderr, "Can't alloc memory in libvlc_event_send" );
 184                 return;
 185             }
 186
 187             listener_cached = array_listeners_cached;
 188             for( i = 0; i < vlc_array_count(&listeners_group->listeners); i++)
 189             {
 190                 listener = vlc_array_item_at_index(&listeners_group->listeners, i);
 191                 memcpy( listener_cached, listener, sizeof(libvlc_event_listener_t) );
 192                 listener_cached++;
 193             }
 194             break;
 195         }
 196     }
 197
 198     if( !listeners_group )
 199     {
 200         free( array_listeners_cached );
 201         vlc_mutex_unlock( &p_em->object_lock );
 202         return;
 203     }
 204
 205     vlc_mutex_unlock( &p_em->object_lock );
 206
 207     vlc_mutex_lock( &p_em->event_sending_lock );
 208     listener_cached = array_listeners_cached;
 209     listeners_group->b_sublistener_removed = false;
 210     for( i = 0; i < i_cached_listeners; i++ )
 211     {
 212         if(listener_cached->is_asynchronous)
 213         {
 214             /* The listener wants not to block the emitter during event callback */
 215             libvlc_event_async_dispatch(p_em, listener_cached, p_event);
 216         }
 217         else
 218         {
 219             /* The listener wants to block the emitter during event callback */
 220
 221             listener_cached->pf_callback( p_event, listener_cached->p_user_data );
 222             listener_cached++;
 223
 224             if( listeners_group->b_sublistener_removed )
 225             {
 226                 /* If a callback was removed, this gets called */
 227                 bool valid_listener;
 228                 vlc_mutex_lock( &p_em->object_lock );
 229                 valid_listener = group_contains_listener( listeners_group, listener_cached );
 230                 vlc_mutex_unlock( &p_em->object_lock );
 231                 if( !valid_listener )
 232                 {
 233                     listener_cached++;
 234                     continue;
 235                 }
 236             }
 237         }
 238     }
 239     vlc_mutex_unlock( &p_em->event_sending_lock );
 240
 241     free( array_listeners_cached );
 242 }
 243
 244 /*
 245  * Public libvlc functions
 246  */
 247
 248 /**************************************************************************
 249  *       libvlc_event_type_name (public) :
 250  *
 251  * Get the char * name of an event type.
 252  **************************************************************************/
 253 static const char event_type_to_name[][35] =
 254 {
 255 #define EVENT(a) [a]=#a
 256     EVENT(libvlc_MediaMetaChanged),
 257     EVENT(libvlc_MediaSubItemAdded),
 258     EVENT(libvlc_MediaDurationChanged),
 259     EVENT(libvlc_MediaPreparsedChanged),
 260     EVENT(libvlc_MediaFreed),
 261     EVENT(libvlc_MediaStateChanged),
 262
 263     EVENT(libvlc_MediaPlayerNothingSpecial),
 264     EVENT(libvlc_MediaPlayerOpening),
 265     EVENT(libvlc_MediaPlayerBuffering),
 266     EVENT(libvlc_MediaPlayerPlaying),
 267     EVENT(libvlc_MediaPlayerPaused),
 268     EVENT(libvlc_MediaPlayerStopped),
 269     EVENT(libvlc_MediaPlayerForward),
 270     EVENT(libvlc_MediaPlayerBackward),
 271     EVENT(libvlc_MediaPlayerEndReached),
 272     EVENT(libvlc_MediaPlayerTimeChanged),
 273     EVENT(libvlc_MediaPlayerTitleChanged),
 274     EVENT(libvlc_MediaPlayerPositionChanged),
 275     EVENT(libvlc_MediaPlayerSeekableChanged),
 276     EVENT(libvlc_MediaPlayerPausableChanged),
 277
 278     EVENT(libvlc_MediaListItemAdded),
 279     EVENT(libvlc_MediaListWillAddItem),
 280     EVENT(libvlc_MediaListItemDeleted),
 281     EVENT(libvlc_MediaListWillDeleteItem),
 282
 283     EVENT(libvlc_MediaListViewItemAdded),
 284     EVENT(libvlc_MediaListViewWillAddItem),
 285     EVENT(libvlc_MediaListViewItemDeleted),
 286     EVENT(libvlc_MediaListViewWillDeleteItem),
 287
 288     EVENT(libvlc_MediaListPlayerPlayed),
 289     EVENT(libvlc_MediaListPlayerNextItemSet),
 290     EVENT(libvlc_MediaListPlayerStopped),
 291
 292     EVENT(libvlc_MediaDiscovererStarted),
 293     EVENT(libvlc_MediaDiscovererEnded),
 294
 295     EVENT(libvlc_MediaPlayerSnapshotTaken),
 296 #undef EVENT
 297 };
 298
 299 static const char unkwown_event_name[] = "Unknown Event";
 300
 301 const char * libvlc_event_type_name( libvlc_event_type_t event_type )
 302 {
 303     if( event_type >= sizeof(event_type_to_name)/sizeof(event_type_to_name[0]))
 304         return unkwown_event_name;
 305     return event_type_to_name[event_type];
 306 }
 307
 308 /**************************************************************************
 309  *       event_attach (internal) :
 310  *
 311  * Add a callback for an event.
 312  **************************************************************************/
 313 static
 314 void event_attach( libvlc_event_manager_t * p_event_manager,
 315                          libvlc_event_type_t event_type,
 316                          libvlc_callback_t pf_callback,
 317                          void *p_user_data,
 318                          bool is_asynchronous,
 319                          libvlc_exception_t *p_e )
 320 {
 321     libvlc_event_listeners_group_t * listeners_group;
 322     libvlc_event_listener_t * listener;
 323     int i;
 324
 325     listener = malloc(sizeof(libvlc_event_listener_t));
 326     if( !listener )
 327     {
 328         libvlc_exception_raise( p_e, "No Memory left" );
 329         return;
 330     }
 331
 332     listener->event_type = event_type;
 333     listener->p_user_data = p_user_data;
 334     listener->pf_callback = pf_callback;
 335     listener->is_asynchronous = is_asynchronous;
 336
 337     vlc_mutex_lock( &p_event_manager->object_lock );
 338     for( i = 0; i < vlc_array_count(&p_event_manager->listeners_groups); i++ )
 339     {
 340         listeners_group = vlc_array_item_at_index(&p_event_manager->listeners_groups, i);
 341         if( listeners_group->event_type == listener->event_type )
 342         {
 343             vlc_array_append( &listeners_group->listeners, listener );
 344             vlc_mutex_unlock( &p_event_manager->object_lock );
 345             return;
 346         }
 347     }
 348     vlc_mutex_unlock( &p_event_manager->object_lock );
 349
 350     free(listener);
 351     libvlc_exception_raise( p_e,
 352                            "This object event manager doesn't know about '%s' events",
 353                            libvlc_event_type_name(event_type));
 354 }
 355
 356 /**************************************************************************
 357  *       libvlc_event_attach (public) :
 358  *
 359  * Add a callback for an event.
 360  **************************************************************************/
 361 void libvlc_event_attach( libvlc_event_manager_t * p_event_manager,
 362                          libvlc_event_type_t event_type,
 363                          libvlc_callback_t pf_callback,
 364                          void *p_user_data,
 365                          libvlc_exception_t *p_e )
 366 {
 367     event_attach(p_event_manager, event_type, pf_callback, p_user_data, false /* synchronous */, p_e);
 368 }
 369
 370 /**************************************************************************
 371  *       libvlc_event_attach (public) :
 372  *
 373  * Add a callback for an event.
 374  **************************************************************************/
 375 void libvlc_event_attach_async( libvlc_event_manager_t * p_event_manager,
 376                          libvlc_event_type_t event_type,
 377                          libvlc_callback_t pf_callback,
 378                          void *p_user_data,
 379                          libvlc_exception_t *p_e )
 380 {
 381     event_attach(p_event_manager, event_type, pf_callback, p_user_data, true /* asynchronous */, p_e);
 382 }
 383
 384 /**************************************************************************
 385  *       libvlc_event_detach (public) :
 386  *
 387  * Remove a callback for an event.
 388  **************************************************************************/
 389 void libvlc_event_detach( libvlc_event_manager_t *p_event_manager,
 390                                      libvlc_event_type_t event_type,
 391                                      libvlc_callback_t pf_callback,
 392                                      void *p_user_data,
 393                                      libvlc_exception_t *p_e )
 394 {
 395     libvlc_event_listeners_group_t * listeners_group;
 396     libvlc_event_listener_t * listener;
 397     int i, j;
 398     bool found = false;
 399
 400     vlc_mutex_lock( &p_event_manager->event_sending_lock );
 401     vlc_mutex_lock( &p_event_manager->object_lock );
 402     for( i = 0; i < vlc_array_count(&p_event_manager->listeners_groups); i++)
 403     {
 404         listeners_group = vlc_array_item_at_index(&p_event_manager->listeners_groups, i);
 405         if( listeners_group->event_type == event_type )
 406         {
 407             for( j = 0; j < vlc_array_count(&listeners_group->listeners); j++)
 408             {
 409                 listener = vlc_array_item_at_index(&listeners_group->listeners, j);
 410                 if( listener->event_type == event_type &&
 411                     listener->pf_callback == pf_callback &&
 412                     listener->p_user_data == p_user_data )
 413                 {
 414                     /* that's our listener */
 415
 416                     /* Mark this group as edited so that libvlc_event_send
 417                      * will recheck what listener to call */
 418                     listeners_group->b_sublistener_removed = false;
 419
 420                     free( listener );
 421                     vlc_array_remove( &listeners_group->listeners, j );
 422                     found = true;
 423                     break;
 424                 }
 425             }
 426         }
 427     }
 428     vlc_mutex_unlock( &p_event_manager->object_lock );
 429     vlc_mutex_unlock( &p_event_manager->event_sending_lock );
 430
 431     /* Now make sure any pending async event won't get fired after that point */
 432     libvlc_event_listener_t listener_to_remove;
 433     listener_to_remove.event_type  = event_type;
 434     listener_to_remove.pf_callback = pf_callback;
 435     listener_to_remove.p_user_data = p_user_data;
 436     listener_to_remove.is_asynchronous = true;
 437
 438     libvlc_event_async_ensure_listener_removal(p_event_manager, &listener_to_remove);
 439
 440     if(!found)
 441     {
 442         libvlc_exception_raise( p_e,
 443                                "This object event manager doesn't know about '%s,%p,%p' event observer",
 444                                libvlc_event_type_name(event_type), pf_callback, p_user_data );
 445     }
 446 }