lib/event.c

   1 /*****************************************************************************
   2  * event.c: New libvlc event control API
   3  *****************************************************************************
   4  * Copyright (C) 2007-2010 VLC authors and VideoLAN
   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 it
  11  * under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * 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 <assert.h>
  30 #include <errno.h>
  31
  32 #include <vlc/libvlc.h>
  33 #include "libvlc_internal.h"
  34
  35 #include <vlc_common.h>
  36
  37 /*
  38  * Event Handling
  39  */
  40
  41 /* Example usage
  42  *
  43  * struct libvlc_cool_object_t
  44  * {
  45  *        ...
  46  *        libvlc_event_manager_t event_manager;
  47  *        ...
  48  * }
  49  *
  50  * libvlc_my_cool_object_new()
  51  * {
  52  *        ...
  53  *        libvlc_event_manager_init(&p_self->event_manager, p_self)
  54  *        ...
  55  * }
  56  *
  57  * libvlc_my_cool_object_release()
  58  * {
  59  *         ...
  60  *         libvlc_event_manager_release(&p_self->event_manager);
  61  *         ...
  62  * }
  63  *
  64  * libvlc_my_cool_object_do_something()
  65  * {
  66  *        ...
  67  *        libvlc_event_t event;
  68  *        event.type = libvlc_MyCoolObjectDidSomething;
  69  *        event.u.my_cool_object_did_something.what_it_did = kSomething;
  70  *        libvlc_event_send(&p_self->event_manager, &event);
  71  * }
  72  * */
  73
  74 typedef struct libvlc_event_listener_t
  75 {
  76     libvlc_event_type_t event_type;
  77     void *              p_user_data;
  78     libvlc_callback_t   pf_callback;
  79 } libvlc_event_listener_t;
  80
  81 /*
  82  * Internal libvlc functions
  83  */
  84
  85 void libvlc_event_manager_init(libvlc_event_manager_t *em, void *obj)
  86 {
  87     em->p_obj = obj;
  88     vlc_array_init(&em->listeners);
  89     vlc_mutex_init_recursive(&em->lock);
  90 }
  91
  92 void libvlc_event_manager_destroy(libvlc_event_manager_t *em)
  93 {
  94     vlc_mutex_destroy(&em->lock);
  95
  96     for (size_t i = 0; i < vlc_array_count(&em->listeners); i++)
  97         free(vlc_array_item_at_index(&em->listeners, i));
  98
  99     vlc_array_clear(&em->listeners);
 100 }
 101
 102 /**************************************************************************
 103  *       libvlc_event_send (internal) :
 104  *
 105  * Send a callback.
 106  **************************************************************************/
 107 void libvlc_event_send( libvlc_event_manager_t * p_em,
 108                         libvlc_event_t * p_event )
 109 {
 110     /* Fill event with the sending object now */
 111     p_event->p_obj = p_em->p_obj;
 112
 113     vlc_mutex_lock(&p_em->lock);
 114     for (size_t i = 0; i < vlc_array_count(&p_em->listeners); i++)
 115     {
 116         libvlc_event_listener_t *listener;
 117
 118         listener = vlc_array_item_at_index(&p_em->listeners, i);
 119         if (listener->event_type == p_event->type)
 120             listener->pf_callback(p_event, listener->p_user_data);
 121     }
 122     vlc_mutex_unlock(&p_em->lock);
 123 }
 124
 125 /*
 126  * Public libvlc functions
 127  */
 128
 129 #define DEF( a ) { libvlc_##a, #a, },
 130
 131 typedef struct
 132 {
 133     int type;
 134     const char name[40];
 135 } event_name_t;
 136
 137 static const event_name_t event_list[] = {
 138     DEF(MediaMetaChanged)
 139     DEF(MediaSubItemAdded)
 140     DEF(MediaDurationChanged)
 141     DEF(MediaParsedChanged)
 142     DEF(MediaFreed)
 143     DEF(MediaStateChanged)
 144     DEF(MediaSubItemTreeAdded)
 145
 146     DEF(MediaPlayerMediaChanged)
 147     DEF(MediaPlayerNothingSpecial)
 148     DEF(MediaPlayerOpening)
 149     DEF(MediaPlayerBuffering)
 150     DEF(MediaPlayerPlaying)
 151     DEF(MediaPlayerPaused)
 152     DEF(MediaPlayerStopped)
 153     DEF(MediaPlayerForward)
 154     DEF(MediaPlayerBackward)
 155     DEF(MediaPlayerEndReached)
 156     DEF(MediaPlayerEncounteredError)
 157     DEF(MediaPlayerTimeChanged)
 158     DEF(MediaPlayerPositionChanged)
 159     DEF(MediaPlayerSeekableChanged)
 160     DEF(MediaPlayerPausableChanged)
 161     DEF(MediaPlayerTitleChanged)
 162     DEF(MediaPlayerSnapshotTaken)
 163     DEF(MediaPlayerLengthChanged)
 164     DEF(MediaPlayerVout)
 165     DEF(MediaPlayerScrambledChanged)
 166     DEF(MediaPlayerESAdded)
 167     DEF(MediaPlayerESDeleted)
 168     DEF(MediaPlayerESSelected)
 169     DEF(MediaPlayerCorked)
 170     DEF(MediaPlayerUncorked)
 171     DEF(MediaPlayerMuted)
 172     DEF(MediaPlayerUnmuted)
 173     DEF(MediaPlayerAudioVolume)
 174     DEF(MediaPlayerAudioDevice)
 175     DEF(MediaPlayerChapterChanged)
 176
 177     DEF(MediaListItemAdded)
 178     DEF(MediaListWillAddItem)
 179     DEF(MediaListItemDeleted)
 180     DEF(MediaListWillDeleteItem)
 181     DEF(MediaListEndReached)
 182
 183     DEF(MediaListViewItemAdded)
 184     DEF(MediaListViewWillAddItem)
 185     DEF(MediaListViewItemDeleted)
 186     DEF(MediaListViewWillDeleteItem)
 187
 188     DEF(MediaListPlayerPlayed)
 189     DEF(MediaListPlayerNextItemSet)
 190     DEF(MediaListPlayerStopped)
 191
 192     DEF(VlmMediaAdded)
 193     DEF(VlmMediaRemoved)
 194     DEF(VlmMediaChanged)
 195     DEF(VlmMediaInstanceStarted)
 196     DEF(VlmMediaInstanceStopped)
 197     DEF(VlmMediaInstanceStatusInit)
 198     DEF(VlmMediaInstanceStatusOpening)
 199     DEF(VlmMediaInstanceStatusPlaying)
 200     DEF(VlmMediaInstanceStatusPause)
 201     DEF(VlmMediaInstanceStatusEnd)
 202     DEF(VlmMediaInstanceStatusError)
 203 };
 204 #undef DEF
 205
 206 static const char unknown_event_name[] = "Unknown Event";
 207
 208 static int evcmp( const void *a, const void *b )
 209 {
 210     return (*(const int *)a) - ((event_name_t *)b)->type;
 211 }
 212
 213 const char * libvlc_event_type_name( int event_type )
 214 {
 215     const event_name_t *p;
 216
 217     p = bsearch( &event_type, event_list,
 218                  sizeof(event_list)/sizeof(event_list[0]), sizeof(*p),
 219                  evcmp );
 220     return p ? p->name : unknown_event_name;
 221 }
 222
 223 /**************************************************************************
 224  *       libvlc_event_attach (public) :
 225  *
 226  * Add a callback for an event.
 227  **************************************************************************/
 228 int libvlc_event_attach(libvlc_event_manager_t *em, libvlc_event_type_t type,
 229                         libvlc_callback_t callback, void *opaque)
 230 {
 231     libvlc_event_listener_t *listener = malloc(sizeof (*listener));
 232     if (unlikely(listener == NULL))
 233         return ENOMEM;
 234
 235     listener->event_type = type;
 236     listener->p_user_data = opaque;
 237     listener->pf_callback = callback;
 238
 239     int i_ret;
 240     vlc_mutex_lock(&em->lock);
 241     if(vlc_array_append(&em->listeners, listener) != 0)
 242     {
 243         i_ret = VLC_EGENERIC;
 244         free(listener);
 245     }
 246     else
 247         i_ret = VLC_SUCCESS;
 248     vlc_mutex_unlock(&em->lock);
 249     return i_ret;
 250 }
 251
 252 /**************************************************************************
 253  *       libvlc_event_detach (public) :
 254  *
 255  * Remove a callback for an event.
 256  **************************************************************************/
 257 void libvlc_event_detach(libvlc_event_manager_t *em, libvlc_event_type_t type,
 258                          libvlc_callback_t callback, void *opaque)
 259 {
 260     vlc_mutex_lock(&em->lock);
 261     for (size_t i = 0; i < vlc_array_count(&em->listeners); i++)
 262     {
 263          libvlc_event_listener_t *listener;
 264
 265          listener = vlc_array_item_at_index(&em->listeners, i);
 266
 267          if (listener->event_type == type
 268           && listener->pf_callback == callback
 269           && listener->p_user_data == opaque)
 270          {   /* that's our listener */
 271              vlc_array_remove(&em->listeners, i);
 272              vlc_mutex_unlock(&em->lock);
 273              free(listener);
 274              return;
 275          }
 276     }
 277     abort();
 278 }