include/vlc_playlist.h

   1 /*****************************************************************************
   2  * vlc_playlist.h : Playlist functions
   3  *****************************************************************************
   4  * Copyright (C) 1999-2004 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Samuel Hocevar <sam@zoy.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #ifndef VLC_PLAYLIST_H_
  25 #define VLC_PLAYLIST_H_
  26
  27 # ifdef __cplusplus
  28 extern "C" {
  29 # endif
  30
  31 #include <vlc_events.h>
  32
  33 TYPEDEF_ARRAY(playlist_item_t*, playlist_item_array_t)
  34
  35 struct intf_thread_t;
  36
  37 /**
  38  * \defgroup playlist VLC playlist
  39  * VLC playlist controls
  40  * @{
  41  * \file
  42  * VLC playlist control interface
  43  *
  44  * The VLC playlist system has a tree structure. This allows advanced
  45  * categorization, like for SAP streams (which are grouped by "sap groups").
  46  *
  47  * The base structure for all playlist operations is the playlist_item_t.
  48  * This is essentially a node within the playlist tree. Each playlist item
  49  * references an input_item_t which contains the input stream info, such as
  50  * location, name and meta-data.
  51  *
  52  * A playlist item is uniquely identified by its input item:
  53  * \ref playlist_ItemGetByInput(). A single input item cannot be used by more
  54  * than one playlist item at a time; if necessary, a copy of the input item can
  55  * be made instead.
  56  *
  57  * The same playlist tree is visible to all user interfaces. To arbitrate
  58  * access, a lock is used, see \ref playlist_Lock() and \ref playlist_Unlock().
  59  *
  60  * Under the playlist root item node, the top-level items are the main
  61  * media sources and include:
  62  * - the actual playlist,
  63  * - the media library,
  64  * - the service discovery root node, whose children are services discovery
  65  *   module instances.
  66  *
  67  * So, here is an example:
  68  * \verbatim
  69  * Inputs array
  70  *  - input 1 -> name = foo 1 uri = ...
  71  *  - input 2 -> name = foo 2 uri = ...
  72  *
  73  * Playlist items tree
  74  * - playlist (id 1)
  75  *    - category 1 (id 2)
  76  *      - foo 2 (id 6 - input 2)
  77  * - media library (id 2)
  78  *    - foo 1 (id 5 - input 1)
  79  * \endverbatim
  80  *
  81  * Sometimes, an item creates subitems. This happens for the directory access
  82  * for example. In that case, if the item is under the "playlist" top-level
  83  * item and playlist is configured to be flat then the item will be deleted and
  84  * replaced with new subitems. If the item is under another top-level item, it
  85  * will be transformed to a node and removed from the list of all items without
  86  * nodes.
  87  *
  88  * For "standard" item addition, you can use playlist_Add(), playlist_AddExt()
  89  * (more options) or playlist_AddInput() if you already created your input
  90  * item. This will add the item at the root of "Playlist" or of "Media library"
  91  * in each of the two trees.
  92  *
  93  * You can create nodes with playlist_NodeCreate() and can create items from
  94  * existing input items to be placed under any node with
  95  * playlist_NodeAddInput().
  96  *
  97  * To delete an item, use playlist_NodeDelete( p_item ).
  98  *
  99  * The playlist defines the following event variables:
 100  *
 101  * - "item-change": It will contain a pointer to the input_item_t of a
 102  * changed input item monitored by the playlist.
 103  *
 104  * - "playlist-item-append": It will contain a pointer to a playlist_item_t.
 105  * - "playlist-item-deleted": It will contain a pointer to the playlist_item_t
 106  * about to be deleted.
 107  *
 108  * - "leaf-to-parent": It will contain the playlist_item_t->i_id of an item that is transformed
 109  *   into a node.
 110  *
 111  * The playlist contains rate-variable which is propagated to current input if
 112  * available also rate-slower/rate-faster is in use.
 113  */
 114
 115 /** Helper structure to export to file part of the playlist */
 116 typedef struct playlist_export_t
 117 {
 118     VLC_COMMON_MEMBERS
 119     char *base_url;
 120     FILE *p_file;
 121     playlist_item_t *p_root;
 122 } playlist_export_t;
 123
 124 /** playlist item / node */
 125 struct playlist_item_t
 126 {
 127     input_item_t           *p_input;    /**< Linked input item */
 128
 129     playlist_item_t      **pp_children; /**< Children nodes/items */
 130     playlist_item_t       *p_parent;    /**< Item parent */
 131     int                    i_children;  /**< Number of children, -1 if not a node */
 132     unsigned               i_nb_played; /**< Times played */
 133
 134     int                    i_id;        /**< Playlist item specific id */
 135     uint8_t                i_flags;     /**< Flags \see playlist_item_flags_e */
 136 };
 137
 138 typedef enum {
 139     PLAYLIST_DBL_FLAG          = 0x04,  /**< Is it disabled ? */
 140     PLAYLIST_RO_FLAG           = 0x08,  /**< Write-enabled ? */
 141     PLAYLIST_SUBITEM_STOP_FLAG = 0x40,  /**< Must playlist stop if the item gets subitems ?*/
 142     PLAYLIST_NO_INHERIT_FLAG   = 0x80,  /**< Will children inherit flags the R/O flag ? */
 143 } playlist_item_flags_e;
 144
 145 /** Playlist status */
 146 typedef enum
 147 { PLAYLIST_STOPPED,PLAYLIST_RUNNING,PLAYLIST_PAUSED } playlist_status_t;
 148
 149 /** Structure containing information about the playlist */
 150 struct playlist_t
 151 {
 152     VLC_COMMON_MEMBERS
 153
 154     playlist_item_array_t items; /**< Arrays of items */
 155
 156     playlist_item_array_t current; /**< Items currently being played */
 157     int                   i_current_index; /**< Index in current array */
 158
 159     /* Predefined items */
 160     playlist_item_t  root;
 161     playlist_item_t *p_playing;
 162     playlist_item_t *p_media_library;
 163 };
 164
 165 /* A bit of macro magic to generate an enum out of the following list,
 166  * and later, to generate a list of static functions out of the same list.
 167  * There is also SORT_RANDOM, which is always last and handled specially.
 168  */
 169 #define VLC_DEFINE_SORT_FUNCTIONS \
 170     DEF( SORT_ID )\
 171     DEF( SORT_TITLE )\
 172     DEF( SORT_TITLE_NODES_FIRST )\
 173     DEF( SORT_ARTIST )\
 174     DEF( SORT_GENRE )\
 175     DEF( SORT_DURATION )\
 176     DEF( SORT_TITLE_NUMERIC )\
 177     DEF( SORT_ALBUM )\
 178     DEF( SORT_TRACK_NUMBER )\
 179     DEF( SORT_DESCRIPTION )\
 180     DEF( SORT_RATING )\
 181     DEF( SORT_URI )\
 182     DEF( SORT_DISC_NUMBER )\
 183     DEF( SORT_DATE )
 184
 185 #define DEF( s ) s,
 186 enum
 187 {
 188     VLC_DEFINE_SORT_FUNCTIONS
 189     SORT_RANDOM,
 190     NUM_SORT_FNS=SORT_RANDOM
 191 };
 192 #undef  DEF
 193 #ifndef VLC_INTERNAL_PLAYLIST_SORT_FUNCTIONS
 194 #undef  VLC_DEFINE_SORT_FUNCTIONS
 195 #endif
 196
 197 enum
 198 {
 199     ORDER_NORMAL = 0,
 200     ORDER_REVERSE = 1,
 201 };
 202
 203 /* Used by playlist_Import */
 204 #define PLAYLIST_GO              0x0004
 205
 206 #define PLAYLIST_END           -1
 207
 208 enum pl_locked_state
 209 {
 210     pl_Locked = true,
 211     pl_Unlocked = false
 212 };
 213
 214 /*****************************************************************************
 215  * Prototypes
 216  *****************************************************************************/
 217
 218 /* Helpers */
 219 #define PL_LOCK playlist_Lock( p_playlist )
 220 #define PL_UNLOCK playlist_Unlock( p_playlist )
 221 #define PL_ASSERT_LOCKED playlist_AssertLocked( p_playlist )
 222
 223 /** Playlist commands */
 224 enum {
 225     PLAYLIST_PLAY,      /**< No arg.                            res=can fail*/
 226     PLAYLIST_VIEWPLAY,  /**< arg1= playlist_item_t*,*/
 227                         /**  arg2 = playlist_item_t*          , res=can fail */
 228     PLAYLIST_TOGGLE_PAUSE, /**< No arg                          res=can fail */
 229     PLAYLIST_STOP,      /**< No arg                             res=can fail*/
 230     PLAYLIST_SKIP,      /**< arg1=int,                          res=can fail*/
 231     PLAYLIST_PAUSE,     /**< No arg */
 232     PLAYLIST_RESUME,    /**< No arg */
 233 };
 234
 235 #define playlist_Play(p) playlist_Control(p,PLAYLIST_PLAY, pl_Unlocked )
 236 #define playlist_TogglePause(p) \
 237         playlist_Control(p, PLAYLIST_TOGGLE_PAUSE, pl_Unlocked)
 238 #define playlist_Stop(p) playlist_Control(p,PLAYLIST_STOP, pl_Unlocked )
 239 #define playlist_Next(p) playlist_Control(p,PLAYLIST_SKIP, pl_Unlocked, 1)
 240 #define playlist_Prev(p) playlist_Control(p,PLAYLIST_SKIP, pl_Unlocked, -1)
 241 #define playlist_Skip(p,i) playlist_Control(p,PLAYLIST_SKIP, pl_Unlocked,  (i) )
 242 #define playlist_Pause(p) \
 243         playlist_Control(p, PLAYLIST_PAUSE, pl_Unlocked)
 244 #define playlist_Resume(p) \
 245         playlist_Control(p, PLAYLIST_RESUME, pl_Unlocked)
 246
 247 /**
 248  * Locks the playlist.
 249  *
 250  * This function locks the playlist. While the playlist is locked, no other
 251  * thread can modify the playlist tree layout or current playing item and node.
 252  *
 253  * Locking the playlist is necessary before accessing, either for reading or
 254  * writing, any playlist item.
 255  *
 256  * \note Because of the potential for lock inversion / deadlocks, locking the
 257  * playlist shall not be attemped while holding an input item lock. An input
 258  * item lock can be acquired while holding the playlist lock.
 259  *
 260  * While holding the playlist lock, a thread shall not attempt to:
 261  * - probe, initialize or deinitialize a module or a plugin,
 262  * - install or deinstall a variable or event callback,
 263  * - set a variable or trigger a variable callback, with the sole exception
 264  *   of the playlist core triggering add/remove/leaf item callbacks,
 265  * - invoke a module/plugin callback other than:
 266  *   - playlist export,
 267  *   - logger message callback.
 268  */
 269 VLC_API void playlist_Lock( playlist_t * );
 270
 271 /**
 272  * Unlocks the playlist.
 273  *
 274  * This function unlocks the playlist, allowing other threads to lock it. The
 275  * calling thread must have called playlist_Lock() before.
 276  *
 277  * This function invalidates all or any playlist item pointers.
 278  * There are no ways to ensure that playlist items are not modified or deleted
 279  * by another thread past this function call.
 280  *
 281  * To retain a reference to a playlist item while not holding the playlist
 282  * lock, a thread should take a reference to the input item within the
 283  * playlist item before unlocking. If this is not practical, then the thread
 284  * can store the playlist item ID (i_id) before unlocking.
 285  * Either way, this will not ensure that the playlist item is not deleted, so
 286  * the thread must be ready to handle that case later when calling
 287  * playlist_ItemGetByInput() or playlist_ItemGetById().
 288  *
 289  * Furthermore, if ID is used, then the playlist item might be deleted, and
 290  * another item could be assigned the same ID. To avoid that problem, use
 291  * the input item instead of the ID.
 292  */
 293 VLC_API void playlist_Unlock( playlist_t * );
 294
 295 VLC_API void playlist_AssertLocked( playlist_t * );
 296 VLC_API void playlist_Deactivate( playlist_t * );
 297
 298 /**
 299  * Do a playlist action.
 300  * If there is something in the playlist then you can do playlist actions.
 301  * Possible queries are listed in vlc_common.h
 302  * \param p_playlist the playlist to do the command on
 303  * \param i_query the command to do
 304  * \param b_locked TRUE if playlist is locked when entering this function
 305  * \param variable number of arguments
 306  */
 307 VLC_API void playlist_Control( playlist_t *p_playlist, int i_query, bool b_locked, ...  );
 308
 309 static inline void playlist_ViewPlay(playlist_t *pl, playlist_item_t *node,
 310                                      playlist_item_t *item)
 311 {
 312     playlist_Control(pl, PLAYLIST_VIEWPLAY, pl_Locked, node, item);
 313 }
 314
 315 /** Get current playing input. The object is retained.
 316  */
 317 VLC_API input_thread_t * playlist_CurrentInput( playlist_t *p_playlist ) VLC_USED;
 318 VLC_API input_thread_t *playlist_CurrentInputLocked( playlist_t *p_playlist ) VLC_USED;
 319
 320 /** Get the duration of all items in a node.
 321  */
 322 VLC_API mtime_t playlist_GetNodeDuration( playlist_item_t * );
 323
 324 /** Clear the playlist
 325  * \param b_locked TRUE if playlist is locked when entering this function
 326  */
 327 VLC_API void playlist_Clear( playlist_t *, bool );
 328
 329 /* Playlist sorting */
 330 VLC_API int playlist_TreeMove( playlist_t *, playlist_item_t *, playlist_item_t *, int );
 331 VLC_API int playlist_TreeMoveMany( playlist_t *, int, playlist_item_t **, playlist_item_t *, int );
 332 VLC_API int playlist_RecursiveNodeSort( playlist_t *, playlist_item_t *,int, int );
 333
 334 VLC_API playlist_item_t * playlist_CurrentPlayingItem( playlist_t * ) VLC_USED;
 335 VLC_API int playlist_Status( playlist_t * );
 336
 337 /**
 338  * Export a node of the playlist to a certain type of playlistfile
 339  * \param b_playlist true for the playlist, false for the media library
 340  * \param psz_filename the location where the exported file will be saved
 341  * \param psz_type the type of playlist file to create (m3u, pls, ..)
 342  * \return VLC_SUCCESS on success
 343  */
 344 VLC_API int playlist_Export( playlist_t *p_playlist, const char *psz_name,
 345                              bool b_playlist, const char *psz_type );
 346
 347 /**
 348  * Open a playlist file, add its content to the current playlist
 349  */
 350 VLC_API int playlist_Import( playlist_t *p_playlist, const char *psz_file );
 351
 352 /********************** Services discovery ***********************/
 353
 354 /** Add a service discovery module */
 355 VLC_API int playlist_ServicesDiscoveryAdd(playlist_t *, const char *);
 356 /** Remove a services discovery module by name */
 357 VLC_API int playlist_ServicesDiscoveryRemove(playlist_t *, const char *);
 358 /** Check whether a given SD is loaded */
 359 VLC_API bool playlist_IsServicesDiscoveryLoaded( playlist_t *,const char *) VLC_DEPRECATED;
 360 /** Query a services discovery */
 361 VLC_API int playlist_ServicesDiscoveryControl( playlist_t *, const char *, int, ... );
 362
 363
 364
 365 /********************************************************
 366  * Item management
 367  ********************************************************/
 368
 369 /******************** Item addition ********************/
 370 VLC_API int playlist_Add( playlist_t *, const char *, bool );
 371 VLC_API int playlist_AddExt( playlist_t *, const char *, const char *, bool, int, const char *const *, unsigned, bool );
 372 VLC_API int playlist_AddInput( playlist_t *, input_item_t *, bool, bool );
 373 VLC_API playlist_item_t * playlist_NodeAddInput( playlist_t *, input_item_t *, playlist_item_t *, int, int );
 374 VLC_API int playlist_NodeAddCopy( playlist_t *, playlist_item_t *, playlist_item_t *, int );
 375
 376 /********************************** Item search *************************/
 377 VLC_API playlist_item_t * playlist_ItemGetById(playlist_t *, int ) VLC_USED;
 378 VLC_API playlist_item_t *playlist_ItemGetByInput(playlist_t *,
 379                                                  const input_item_t * )
 380 VLC_USED;
 381
 382 VLC_API int playlist_LiveSearchUpdate(playlist_t *, playlist_item_t *, const char *, bool );
 383
 384 /********************************************************
 385  * Tree management
 386  ********************************************************/
 387 /* Node management */
 388 VLC_API playlist_item_t * playlist_NodeCreate( playlist_t *, const char *, playlist_item_t * p_parent, int i_pos, int i_flags );
 389 VLC_API playlist_item_t * playlist_ChildSearchName(playlist_item_t*, const char* ) VLC_USED;
 390 VLC_API void playlist_NodeDelete( playlist_t *, playlist_item_t *, bool );
 391
 392 /**************************
 393  * Audio output management
 394  **************************/
 395
 396 VLC_API audio_output_t *playlist_GetAout( playlist_t * );
 397
 398 #define AOUT_VOLUME_DEFAULT             256
 399 #define AOUT_VOLUME_MAX                 512
 400
 401 VLC_API float playlist_VolumeGet( playlist_t * );
 402 VLC_API int playlist_VolumeSet( playlist_t *, float );
 403 VLC_API int playlist_VolumeUp( playlist_t *, int, float * );
 404 #define playlist_VolumeDown(a, b, c) playlist_VolumeUp(a, -(b), c)
 405 VLC_API int playlist_MuteSet( playlist_t *, bool );
 406 VLC_API int playlist_MuteGet( playlist_t * );
 407
 408 static inline int playlist_MuteToggle( playlist_t *pl )
 409 {
 410     int val = playlist_MuteGet( pl );
 411     if (val >= 0)
 412         val = playlist_MuteSet( pl, !val );
 413     return val;
 414 }
 415
 416 VLC_API void playlist_EnableAudioFilter( playlist_t *, const char *, bool );
 417
 418 /***********************************************************************
 419  * Inline functions
 420  ***********************************************************************/
 421 /** Tell if the playlist is empty */
 422 static inline bool playlist_IsEmpty( playlist_t *p_playlist )
 423 {
 424     PL_ASSERT_LOCKED;
 425     return p_playlist->items.i_size == 0;
 426 }
 427
 428 /** Tell the number of items in the current playing context */
 429 static inline int playlist_CurrentSize( playlist_t *p_playlist )
 430 {
 431     PL_ASSERT_LOCKED;
 432     return p_playlist->current.i_size;
 433 }
 434
 435 /** @} */
 436 # ifdef __cplusplus
 437 }
 438 # endif
 439
 440 #endif