1 /*****************************************************************************
2 * libvlc.h: libvlc external API
3 *****************************************************************************
4 * Copyright (C) 1998-2009 VLC authors and VideoLAN
7 * Authors: Clément Stenac <zorglub@videolan.org>
8 * Jean-Paul Saman <jpsaman@videolan.org>
9 * Pierre d'Herbemont <pdherbemont@videolan.org>
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU Lesser General Public License as published by
13 * the Free Software Foundation; either version 2.1 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU Lesser General Public License for more details.
21 * You should have received a copy of the GNU Lesser General Public License
22 * along with this program; if not, write to the Free Software Foundation,
23 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
24 *****************************************************************************/
28 * This file defines libvlc external API
32 * \defgroup libvlc LibVLC
33 * LibVLC is the external programming interface of the VLC media player.
34 * It is used to embed VLC into other applications or frameworks.
39 #define VLC_LIBVLC_H 1
41 #if defined (WIN32) && defined (DLL_EXPORT)
42 # define LIBVLC_API __declspec(dllexport)
43 #elif defined (__GNUC__) && (__GNUC__ >= 4)
44 # define LIBVLC_API __attribute__((visibility("default")))
50 /* Avoid unhelpful warnings from libvlc with our deprecated APIs */
51 # define LIBVLC_DEPRECATED
52 #elif defined(__GNUC__) && \
53 (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)
54 # define LIBVLC_DEPRECATED __attribute__((deprecated))
56 # define LIBVLC_DEPRECATED
66 #include <vlc/libvlc_structures.h>
68 /** \defgroup libvlc_core LibVLC core
70 * Before it can do anything useful, LibVLC must be initialized.
71 * You can create one (or more) instance(s) of LibVLC in a given process,
72 * with libvlc_new() and destroy them with libvlc_release().
74 * \version Unless otherwise stated, these functions are available
75 * from LibVLC versions numbered 1.1.0 or more.
76 * Earlier versions (0.9.x and 1.0.x) are <b>not</b> compatible.
80 /** \defgroup libvlc_error LibVLC error handling
85 * A human-readable error message for the last LibVLC error in the calling
86 * thread. The resulting string is valid until another error occurs (at least
87 * until the next LibVLC call).
90 * This will be NULL if there was no error.
92 LIBVLC_API const char *libvlc_errmsg (void);
95 * Clears the LibVLC error status for the current thread. This is optional.
96 * By default, the error status is automatically overridden when a new error
97 * occurs, and destroyed when the thread exits.
99 LIBVLC_API void libvlc_clearerr (void);
102 * Sets the LibVLC error status and message for the current thread.
103 * Any previous error is overridden.
104 * \param fmt the format string
105 * \param ap the arguments
106 * \return a nul terminated string in any case
108 LIBVLC_API const char *libvlc_vprinterr (const char *fmt, va_list ap);
111 * Sets the LibVLC error status and message for the current thread.
112 * Any previous error is overridden.
113 * \param fmt the format string
114 * \param args the arguments
115 * \return a nul terminated string in any case
117 LIBVLC_API const char *libvlc_printerr (const char *fmt, ...);
122 * Create and initialize a libvlc instance.
123 * This functions accept a list of "command line" arguments similar to the
124 * main(). These arguments affect the LibVLC instance default configuration.
127 * Arguments are meant to be passed from the command line to LibVLC, just like
128 * VLC media player does. The list of valid arguments depends on the LibVLC
129 * version, the operating system and platform, and set of available LibVLC
130 * plugins. Invalid or unsupported arguments will cause the function to fail
131 * (i.e. return NULL). Also, some arguments may alter the behaviour or
132 * otherwise interfere with other LibVLC functions.
135 * There is absolutely no warranty or promise of forward, backward and
136 * cross-platform compatibility with regards to libvlc_new() arguments.
137 * We recommend that you do not use them, other than when debugging.
139 * \param argc the number of arguments (should be 0)
140 * \param argv list of arguments (should be NULL)
141 * \return the libvlc instance or NULL in case of error
143 LIBVLC_API libvlc_instance_t *
144 libvlc_new( int argc , const char *const *argv );
147 * Decrement the reference count of a libvlc instance, and destroy it
148 * if it reaches zero.
150 * \param p_instance the instance to destroy
152 LIBVLC_API void libvlc_release( libvlc_instance_t *p_instance );
155 * Increments the reference count of a libvlc instance.
156 * The initial reference count is 1 after libvlc_new() returns.
158 * \param p_instance the instance to reference
160 LIBVLC_API void libvlc_retain( libvlc_instance_t *p_instance );
163 * Try to start a user interface for the libvlc instance.
165 * \param p_instance the instance
166 * \param name interface name, or NULL for default
167 * \return 0 on success, -1 on error.
170 int libvlc_add_intf( libvlc_instance_t *p_instance, const char *name );
173 * Registers a callback for the LibVLC exit event. This is mostly useful if
174 * the VLC playlist and/or at least one interface are started with
175 * libvlc_playlist_play() or libvlc_add_intf() respectively.
176 * Typically, this function will wake up your application main loop (from
179 * \note This function should be called before the playlist or interface are
180 * started. Otherwise, there is a small race condition: the exit event could
181 * be raised before the handler is registered.
183 * \param p_instance LibVLC instance
184 * \param cb callback to invoke when LibVLC wants to exit,
185 * or NULL to disable the exit handler (as by default)
186 * \param opaque data pointer for the callback
187 * \warning This function and libvlc_wait() cannot be used at the same time.
190 void libvlc_set_exit_handler( libvlc_instance_t *p_instance,
191 void (*cb) (void *), void *opaque );
194 * Waits until an interface causes the instance to exit.
195 * You should start at least one interface first, using libvlc_add_intf().
197 * \param p_instance the instance
198 * \warning This function wastes one thread doing basically nothing.
199 * libvlc_set_exit_handler() should be used instead.
201 LIBVLC_DEPRECATED LIBVLC_API
202 void libvlc_wait( libvlc_instance_t *p_instance );
205 * Sets the application name. LibVLC passes this as the user agent string
206 * when a protocol requires it.
208 * \param p_instance LibVLC instance
209 * \param name human-readable application name, e.g. "FooBar player 1.2.3"
210 * \param http HTTP User Agent, e.g. "FooBar/1.2.3 Python/2.6.0"
211 * \version LibVLC 1.1.1 or later
214 void libvlc_set_user_agent( libvlc_instance_t *p_instance,
215 const char *name, const char *http );
218 * Retrieve libvlc version.
220 * Example: "1.1.0-git The Luggage"
222 * \return a string containing the libvlc version
224 LIBVLC_API const char * libvlc_get_version(void);
227 * Retrieve libvlc compiler version.
229 * Example: "gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu6)"
231 * \return a string containing the libvlc compiler version
233 LIBVLC_API const char * libvlc_get_compiler(void);
236 * Retrieve libvlc changeset.
238 * Example: "aa9bce0bc4"
240 * \return a string containing the libvlc changeset
242 LIBVLC_API const char * libvlc_get_changeset(void);
245 * Frees an heap allocation returned by a LibVLC function.
246 * If you know you're using the same underlying C run-time as the LibVLC
247 * implementation, then you can call ANSI C free() directly instead.
249 * \param ptr the pointer
251 LIBVLC_API void libvlc_free( void *ptr );
253 /** \defgroup libvlc_event LibVLC asynchronous events
254 * LibVLC emits asynchronous events.
256 * Several LibVLC objects (such @ref libvlc_instance_t as
257 * @ref libvlc_media_player_t) generate events asynchronously. Each of them
258 * provides @ref libvlc_event_manager_t event manager. You can subscribe to
259 * events with libvlc_event_attach() and unsubscribe with
260 * libvlc_event_detach().
265 * Event manager that belongs to a libvlc object, and from whom events can
268 typedef struct libvlc_event_manager_t libvlc_event_manager_t;
270 struct libvlc_event_t;
273 * Type of a LibVLC event.
275 typedef int libvlc_event_type_t;
278 * Callback function notification
279 * \param p_event the event triggering the callback
281 typedef void ( *libvlc_callback_t )( const struct libvlc_event_t *, void * );
284 * Register for an event notification.
286 * \param p_event_manager the event manager to which you want to attach to.
287 * Generally it is obtained by vlc_my_object_event_manager() where
288 * my_object is the object you want to listen to.
289 * \param i_event_type the desired event to which we want to listen
290 * \param f_callback the function to call when i_event_type occurs
291 * \param user_data user provided data to carry with the event
292 * \return 0 on success, ENOMEM on error
294 LIBVLC_API int libvlc_event_attach( libvlc_event_manager_t *p_event_manager,
295 libvlc_event_type_t i_event_type,
296 libvlc_callback_t f_callback,
300 * Unregister an event notification.
302 * \param p_event_manager the event manager
303 * \param i_event_type the desired event to which we want to unregister
304 * \param f_callback the function to call when i_event_type occurs
305 * \param p_user_data user provided data to carry with the event
307 LIBVLC_API void libvlc_event_detach( libvlc_event_manager_t *p_event_manager,
308 libvlc_event_type_t i_event_type,
309 libvlc_callback_t f_callback,
313 * Get an event's type name.
315 * \param event_type the desired event
317 LIBVLC_API const char * libvlc_event_type_name( libvlc_event_type_t event_type );
321 /** \defgroup libvlc_log LibVLC logging
322 * libvlc_log_* functions provide access to the LibVLC messages log.
323 * This is used for logging and debugging.
328 * Logging messages level.
329 * \note Future LibVLC versions may define new levels.
331 enum libvlc_log_level
333 LIBVLC_DEBUG=0, /**< Debug message */
334 LIBVLC_NOTICE=2, /**< Important informational message */
335 LIBVLC_WARNING=3, /**< Warning (potential error) message */
336 LIBVLC_ERROR=4 /**< Error message */
339 typedef struct vlc_log_t libvlc_log_t;
342 * Gets debugging informations about a log message: the name of the VLC module
343 * emitting the message and the message location within the source code.
345 * The returned module name and file name will be NULL if unknown.
346 * The returned line number will similarly be zero if unknown.
348 * \param ctx message context (as passed to the @ref libvlc_log_cb callback)
349 * \param module module name storage (or NULL) [OUT]
350 * \param file source code file name storage (or NULL) [OUT]
351 * \param line source code file line number storage (or NULL) [OUT]
352 * \warning The returned module name and source code file name, if non-NULL,
353 * are only valid until the logging callback returns.
355 * \version LibVLC 2.1.0 or later
357 void libvlc_log_get_context(const libvlc_log_t *ctx, const char **module,
358 const char **file, unsigned *restrict line);
361 * Gets VLC object informations about a log message: the type name of the VLC
362 * object emitting the message, the object header if any and a temporaly-unique
363 * object identifier. These informations are mainly meant for <b>manual</b>
366 * The returned type name may be "generic" if unknown, but it cannot be NULL.
367 * The returned header will be NULL if unset; in current versions, the header
368 * is used to distinguish for VLM inputs.
369 * The returned object ID will be zero if the message is not associated with
372 * \param ctx message context (as passed to the @ref libvlc_log_cb callback)
373 * \param name object name storage (or NULL) [OUT]
374 * \param header object header (or NULL) [OUT]
375 * \param line source code file line number storage (or NULL) [OUT]
376 * \warning The returned module name and source code file name, if non-NULL,
377 * are only valid until the logging callback returns.
379 * \version LibVLC 2.1.0 or later
381 void libvlc_log_get_object(const libvlc_log_t *ctx, const char **name,
382 const char **header, uintptr_t *id);
385 * Callback prototype for LibVLC log message handler.
386 * \param data data pointer as given to libvlc_log_set()
387 * \param level message level (@ref enum libvlc_log_level)
388 * \param ctx message context (meta-informations about the message)
389 * \param fmt printf() format string (as defined by ISO C11)
390 * \param args variable argument list for the format
391 * \note Log message handlers <b>must</b> be thread-safe.
392 * \warning The message context pointer, the format string parameters and the
393 * variable arguments are only valid until the callback returns.
395 typedef void (*libvlc_log_cb)(void *data, int level, const libvlc_log_t *ctx,
396 const char *fmt, va_list args);
399 * Unsets the logging callback for a LibVLC instance. This is rarely needed:
400 * the callback is implicitly unset when the instance is destroyed.
401 * This function will wait for any pending callbacks invocation to complete
402 * (causing a deadlock if called from within the callback).
404 * \version LibVLC 2.1.0 or later
406 LIBVLC_API void libvlc_log_unset( libvlc_instance_t * );
409 * Sets the logging callback for a LibVLC instance.
410 * This function is thread-safe: it will wait for any pending callbacks
411 * invocation to complete.
413 * \param cb callback function pointer
414 * \param data opaque data pointer for the callback function
416 * \note Some log messages (especially debug) are emitted by LibVLC while
417 * is being initialized. These messages cannot be captured with this interface.
419 * \warning A deadlock may occur if this function is called from the callback.
421 * \version LibVLC 2.1.0 or later
423 LIBVLC_API void libvlc_log_set( libvlc_instance_t *,
424 libvlc_log_cb cb, void *data );
428 * Sets up logging to a file.
429 * \param stream FILE pointer opened for writing
430 * (the FILE pointer must remain valid until libvlc_log_unset())
431 * \version LibVLC 2.1.0 or later
433 LIBVLC_API void libvlc_log_set_file( libvlc_instance_t *, FILE *stream );
436 * Always returns minus one.
437 * This function is only provided for backward compatibility.
439 * \param p_instance ignored
442 LIBVLC_DEPRECATED LIBVLC_API
443 unsigned libvlc_get_log_verbosity( const libvlc_instance_t *p_instance );
446 * This function does nothing.
447 * It is only provided for backward compatibility.
449 * \param p_instance ignored
450 * \param level ignored
452 LIBVLC_DEPRECATED LIBVLC_API
453 void libvlc_set_log_verbosity( libvlc_instance_t *p_instance, unsigned level );
456 * This function does nothing useful.
457 * It is only provided for backward compatibility.
459 * \param p_instance libvlc instance
460 * \return an unique pointer or NULL on error
462 LIBVLC_DEPRECATED LIBVLC_API
463 libvlc_log_t *libvlc_log_open( libvlc_instance_t *p_instance );
466 * Frees memory allocated by libvlc_log_open().
468 * \param p_log libvlc log instance or NULL
470 LIBVLC_DEPRECATED LIBVLC_API
471 void libvlc_log_close( libvlc_log_t *p_log );
474 * Always returns zero.
475 * This function is only provided for backward compatibility.
477 * \param p_log ignored
478 * \return always zero
480 LIBVLC_DEPRECATED LIBVLC_API
481 unsigned libvlc_log_count( const libvlc_log_t *p_log );
484 * This function does nothing.
485 * It is only provided for backward compatibility.
487 * \param p_log ignored
489 LIBVLC_DEPRECATED LIBVLC_API
490 void libvlc_log_clear( libvlc_log_t *p_log );
493 * This function does nothing useful.
494 * It is only provided for backward compatibility.
496 * \param p_log ignored
497 * \return an unique pointer or NULL on error or if the parameter was NULL
499 LIBVLC_DEPRECATED LIBVLC_API
500 libvlc_log_iterator_t *libvlc_log_get_iterator( const libvlc_log_t *p_log );
503 * Frees memory allocated by libvlc_log_get_iterator().
505 * \param p_iter libvlc log iterator or NULL
507 LIBVLC_DEPRECATED LIBVLC_API
508 void libvlc_log_iterator_free( libvlc_log_iterator_t *p_iter );
511 * Always returns zero.
512 * This function is only provided for backward compatibility.
514 * \param p_iter ignored
515 * \return always zero
517 LIBVLC_DEPRECATED LIBVLC_API
518 int libvlc_log_iterator_has_next( const libvlc_log_iterator_t *p_iter );
521 * Always returns NULL.
522 * This function is only provided for backward compatibility.
524 * \param p_iter libvlc log iterator or NULL
525 * \param p_buf ignored
526 * \return always NULL
528 LIBVLC_DEPRECATED LIBVLC_API
529 libvlc_log_message_t *libvlc_log_iterator_next( libvlc_log_iterator_t *p_iter,
530 libvlc_log_message_t *p_buf );
535 * Description of a module.
537 typedef struct libvlc_module_description_t
543 struct libvlc_module_description_t *p_next;
544 } libvlc_module_description_t;
547 * Release a list of module descriptions.
549 * \param p_list the list to be released
552 void libvlc_module_description_list_release( libvlc_module_description_t *p_list );
555 * Returns a list of audio filters that are available.
557 * \param p_instance libvlc instance
559 * \return a list of module descriptions. It should be freed with libvlc_module_description_list_release().
560 * In case of an error, NULL is returned.
562 * \see libvlc_module_description_t
563 * \see libvlc_module_description_list_release
566 libvlc_module_description_t *libvlc_audio_filter_list_get( libvlc_instance_t *p_instance );
569 * Returns a list of video filters that are available.
571 * \param p_instance libvlc instance
573 * \return a list of module descriptions. It should be freed with libvlc_module_description_list_release().
574 * In case of an error, NULL is returned.
576 * \see libvlc_module_description_t
577 * \see libvlc_module_description_list_release
580 libvlc_module_description_t *libvlc_video_filter_list_get( libvlc_instance_t *p_instance );
584 /** \defgroup libvlc_clock LibVLC time
585 * These functions provide access to the LibVLC time/clock.
590 * Return the current time as defined by LibVLC. The unit is the microsecond.
591 * Time increases monotonically (regardless of time zone changes and RTC
593 * The origin is arbitrary but consistent across the whole system
594 * (e.g. the system uptim, the time since the system was booted).
595 * \note On systems that support it, the POSIX monotonic clock is used.
598 int64_t libvlc_clock(void);
601 * Return the delay (in microseconds) until a certain timestamp.
602 * \param pts timestamp
603 * \return negative if timestamp is in the past,
604 * positive if it is in the future
606 static inline int64_t libvlc_delay(int64_t pts)
608 return pts - libvlc_clock();
617 #endif /* <vlc/libvlc.h> */