2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000,2004 Wim Taymans <wim@fluendo.com>
5 * gstelement.h: Header for GstElement
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 #ifndef __GST_ELEMENT_H__
25 #define __GST_ELEMENT_H__
27 #include <gst/gstconfig.h>
28 #include <gst/gsttypes.h>
29 #include <gst/gstobject.h>
30 #include <gst/gstpad.h>
31 #include <gst/gstclock.h>
32 #include <gst/gstplugin.h>
33 #include <gst/gstpluginfeature.h>
34 #include <gst/gstindex.h>
35 #include <gst/gstiterator.h>
36 #include <gst/gsttag.h>
40 typedef struct _GstElementDetails GstElementDetails;
42 /* FIXME: need translatable stuff in here (how handle in registry)? */
43 struct _GstElementDetails
46 gchar *longname; /* long, english name */
47 gchar *klass; /* type of element, as hierarchy */
48 gchar *description; /* insights of one form or another */
49 gchar *author; /* who wrote this thing? */
52 gpointer _gst_reserved[GST_PADDING];
55 #define GST_ELEMENT_DETAILS(longname,klass,description,author) \
56 { longname, klass, description, author, GST_PADDING_INIT }
57 #define GST_IS_ELEMENT_DETAILS(details) ( \
58 (details) && ((details)->longname != NULL) && ((details)->klass != NULL) \
59 && ((details)->description != NULL) && ((details)->author != NULL))
61 #define GST_NUM_STATES 4
63 /* NOTE: this probably should be done with an #ifdef to decide
64 * whether to safe-cast or to just do the non-checking cast.
66 #define GST_STATE(obj) (GST_ELEMENT(obj)->current_state)
67 #define GST_STATE_PENDING(obj) (GST_ELEMENT(obj)->pending_state)
68 #define GST_STATE_ERROR(obj) (GST_ELEMENT(obj)->state_error)
70 /* Note: using 8 bit shift mostly "just because", it leaves us enough room to grow <g> */
71 #define GST_STATE_TRANSITION(obj) ((GST_STATE(obj)<<8) | GST_STATE_PENDING(obj))
72 #define GST_STATE_NULL_TO_READY ((GST_STATE_NULL<<8) | GST_STATE_READY)
73 #define GST_STATE_READY_TO_PAUSED ((GST_STATE_READY<<8) | GST_STATE_PAUSED)
74 #define GST_STATE_PAUSED_TO_PLAYING ((GST_STATE_PAUSED<<8) | GST_STATE_PLAYING)
75 #define GST_STATE_PLAYING_TO_PAUSED ((GST_STATE_PLAYING<<8) | GST_STATE_PAUSED)
76 #define GST_STATE_PAUSED_TO_READY ((GST_STATE_PAUSED<<8) | GST_STATE_READY)
77 #define GST_STATE_READY_TO_NULL ((GST_STATE_READY<<8) | GST_STATE_NULL)
79 GST_EXPORT GType _gst_element_type;
81 #define GST_TYPE_ELEMENT (_gst_element_type)
82 #define GST_IS_ELEMENT(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_ELEMENT))
83 #define GST_IS_ELEMENT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_ELEMENT))
84 #define GST_ELEMENT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_ELEMENT, GstElementClass))
85 #define GST_ELEMENT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_ELEMENT, GstElement))
86 #define GST_ELEMENT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_ELEMENT, GstElementClass))
87 #define GST_ELEMENT_CAST(obj) ((GstElement*)(obj))
89 /* convenience functions */
90 #ifdef G_HAVE_ISO_VARARGS
91 #define GST_ELEMENT_QUERY_TYPE_FUNCTION(functionname, ...) \
92 GST_QUERY_TYPE_FUNCTION (GstElement*, functionname, __VA_ARGS__);
93 #define GST_ELEMENT_FORMATS_FUNCTION(functionname, ...) \
94 GST_FORMATS_FUNCTION (GstElement*, functionname, __VA_ARGS__);
95 #define GST_ELEMENT_EVENT_MASK_FUNCTION(functionname, ...) \
96 GST_EVENT_MASK_FUNCTION (GstElement*, functionname, __VA_ARGS__);
97 #elif defined(G_HAVE_GNUC_VARARGS)
98 #define GST_ELEMENT_QUERY_TYPE_FUNCTION(functionname, a...) \
99 GST_QUERY_TYPE_FUNCTION (GstElement*, functionname, a);
100 #define GST_ELEMENT_FORMATS_FUNCTION(functionname, a...) \
101 GST_FORMATS_FUNCTION (GstElement*, functionname, a);
102 #define GST_ELEMENT_EVENT_MASK_FUNCTION(functionname, a...) \
103 GST_EVENT_MASK_FUNCTION (GstElement*, functionname, a);
108 /* input and output pads aren't directly coupled to each other
109 examples: queues, multi-output async readers, etc. */
110 GST_ELEMENT_DECOUPLED,
111 /* this element, for some reason, has a loop function that performs
112 * an infinite loop without calls to gst_element_yield () */
113 GST_ELEMENT_INFINITE_LOOP,
114 /* there is a new loopfunction ready for placement */
115 GST_ELEMENT_NEW_LOOPFUNC,
116 /* if this element can handle events */
117 GST_ELEMENT_EVENT_AWARE,
119 /* private flags that can be used by the scheduler */
120 GST_ELEMENT_SCHEDULER_PRIVATE1,
121 GST_ELEMENT_SCHEDULER_PRIVATE2,
123 /* ignore state changes from parent */
124 GST_ELEMENT_LOCKED_STATE,
126 /* element is in error */
127 GST_ELEMENT_IN_ERROR,
129 /* use some padding for future expansion */
130 GST_ELEMENT_FLAG_LAST = GST_OBJECT_FLAG_LAST + 16
133 #define GST_ELEMENT_IS_THREAD_SUGGESTED(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_THREAD_SUGGESTED))
134 #define GST_ELEMENT_IS_EVENT_AWARE(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_EVENT_AWARE))
135 #define GST_ELEMENT_IS_DECOUPLED(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_DECOUPLED))
136 #define GST_ELEMENT_IS_LOCKED_STATE(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_LOCKED_STATE))
138 #define GST_ELEMENT_NAME(obj) (GST_OBJECT_NAME(obj))
139 #define GST_ELEMENT_PARENT(obj) (GST_OBJECT_PARENT(obj))
140 #define GST_ELEMENT_SCHEDULER(obj) (GST_ELEMENT_CAST(obj)->scheduler)
141 #define GST_ELEMENT_CLOCK(obj) (GST_ELEMENT_CAST(obj)->clock)
142 #define GST_ELEMENT_PADS(obj) (GST_ELEMENT_CAST(obj)->pads)
146 * @el: the element that throws the error
147 * @domain: like CORE, LIBRARY, RESOURCE or STREAM (see #GstError)
148 * @code: error code defined for that domain (see #GstError)
149 * @message: the message to display (format string and args enclosed in round brackets)
150 * @debug: debugging information for the message (format string and args enclosed in round brackets)
152 * Utility function that elements can use in case they encountered a fatal
153 * data processing error. The pipeline will throw an error signal and the
154 * application will be requested to stop further media processing.
156 #define GST_ELEMENT_ERROR(el, domain, code, message, debug) \
158 gchar *__msg = _gst_element_error_printf message; \
159 gchar *__dbg = _gst_element_error_printf debug; \
161 GST_ERROR_OBJECT (el, "%s", __msg); \
163 GST_ERROR_OBJECT (el, "%s", __dbg); \
164 gst_element_error_full (GST_ELEMENT(el), \
165 GST_ ## domain ## _ERROR, GST_ ## domain ## _ERROR_ ## code, \
166 __msg, __dbg, __FILE__, GST_FUNCTION, __LINE__); \
169 typedef struct _GstElementFactory GstElementFactory;
170 typedef struct _GstElementFactoryClass GstElementFactoryClass;
172 typedef void (*GstElementLoopFunction) (GstElement *element);
174 /* the state change mutexes and conds */
175 #define GST_STATE_GET_LOCK(elem) (GST_ELEMENT_CAST(elem)->state_lock)
176 #define GST_STATE_LOCK(elem) g_mutex_lock(GST_STATE_GET_LOCK(elem))
177 #define GST_STATE_TRYLOCK(elem) g_mutex_trylock(GST_STATE_GET_LOCK(elem))
178 #define GST_STATE_UNLOCK(elem) g_mutex_unlock(GST_STATE_GET_LOCK(elem))
179 #define GST_STATE_GET_COND(elem) (GST_ELEMENT_CAST(elem)->state_cond)
180 #define GST_STATE_WAIT(elem) g_cond_wait (GST_STATE_GET_COND (elem), GST_STATE_GET_LOCK (elem))
181 #define GST_STATE_TIMED_WAIT(elem, timeval) g_cond_timed_wait (GST_STATE_GET_COND (elem), GST_STATE_GET_LOCK (elem),\
183 #define GST_STATE_SIGNAL(elem) g_cond_signal (GST_STATE_GET_COND (elem));
184 #define GST_STATE_BROADCAST(elem) g_cond_broadcast (GST_STATE_GET_COND (elem));
190 /*< public >*/ /* with STATE_LOCK */
194 guint8 current_state;
195 guint8 pending_state;
196 gboolean state_error; /* flag is set when the element has an error in the last state
197 change. it is cleared when doing another state change. */
198 /*< public >*/ /* with LOCK */
200 GstElementLoopFunction loopfunc;
201 GstScheduler *scheduler;
202 /* private pointer for the scheduler */
203 gpointer sched_private;
205 /* allocated clock */
207 GstClockTimeDiff base_time; /* NULL/READY: 0 - PAUSED: current time - PLAYING: difference to clock */
209 /* element pads, these lists can only be iterated while holding
210 * the LOCK or checking the cookie after each LOCK. */
220 gpointer _gst_reserved[GST_PADDING];
223 struct _GstElementClass
225 GstObjectClass parent_class;
228 /* the element details */
229 GstElementDetails details;
231 /* factory that the element was created from */
232 GstElementFactory *elementfactory;
234 /* templates for our pads */
236 gint numpadtemplates;
237 guint32 pad_templ_cookie;
239 /* signal callbacks */
240 void (*state_change) (GstElement *element, GstElementState old, GstElementState state);
241 void (*new_pad) (GstElement *element, GstPad *pad);
242 void (*pad_removed) (GstElement *element, GstPad *pad);
243 void (*no_more_pads) (GstElement *element);
244 void (*error) (GstElement *element, GstElement *source, GError *error, gchar *debug);
245 void (*eos) (GstElement *element);
246 void (*found_tag) (GstElement *element, GstElement *source, const GstTagList *tag_list);
251 /* request/release pads */
252 GstPad* (*request_new_pad) (GstElement *element, GstPadTemplate *templ, const gchar* name);
253 void (*release_pad) (GstElement *element, GstPad *pad);
256 GstElementStateReturn (*change_state) (GstElement *element);
257 GstElementStateReturn (*set_state) (GstElement *element, GstElementState state);
260 gboolean (*release_locks) (GstElement *element);
261 void (*set_scheduler) (GstElement *element, GstScheduler *scheduler);
264 GstClock* (*get_clock) (GstElement *element);
265 void (*set_clock) (GstElement *element, GstClock *clock);
268 GstIndex* (*get_index) (GstElement *element);
269 void (*set_index) (GstElement *element, GstIndex *index);
271 /* query/convert/events functions */
272 const GstEventMask* (*get_event_masks) (GstElement *element);
273 gboolean (*send_event) (GstElement *element, GstEvent *event);
274 const GstFormat* (*get_formats) (GstElement *element);
275 gboolean (*convert) (GstElement *element,
276 GstFormat src_format, gint64 src_value,
277 GstFormat *dest_format, gint64 *dest_value);
278 const GstQueryType* (*get_query_types) (GstElement *element);
279 gboolean (*query) (GstElement *element, GstQueryType type,
280 GstFormat *format, gint64 *value);
283 gpointer _gst_reserved[GST_PADDING];
286 /* element class pad templates */
287 void gst_element_class_add_pad_template (GstElementClass *klass, GstPadTemplate *templ);
288 GstPadTemplate* gst_element_class_get_pad_template (GstElementClass *element_class, const gchar *name);
289 GList* gst_element_class_get_pad_template_list (GstElementClass *element_class);
290 void gst_element_class_set_details (GstElementClass *klass,
291 const GstElementDetails *details);
293 /* element instance */
294 GType gst_element_get_type (void);
296 /* basic name and parentage stuff from GstObject */
297 #define gst_element_get_name(elem) gst_object_get_name(GST_OBJECT(elem))
298 #define gst_element_set_name(elem,name) gst_object_set_name(GST_OBJECT(elem),name)
299 #define gst_element_get_parent(elem) gst_object_get_parent(GST_OBJECT(elem))
300 #define gst_element_set_parent(elem,parent) gst_object_set_parent(GST_OBJECT(elem),parent)
303 gboolean gst_element_requires_clock (GstElement *element);
304 gboolean gst_element_provides_clock (GstElement *element);
305 GstClock* gst_element_get_clock (GstElement *element);
306 void gst_element_set_clock (GstElement *element, GstClock *clock);
307 GstClockReturn gst_element_clock_wait (GstElement *element,
308 GstClockID id, GstClockTimeDiff *jitter);
309 GstClockTime gst_element_get_time (GstElement *element);
310 gboolean gst_element_wait (GstElement *element, GstClockTime timestamp);
311 void gst_element_set_time (GstElement *element, GstClockTime time);
312 void gst_element_set_time_delay (GstElement *element, GstClockTime time, GstClockTime delay);
314 void gst_element_adjust_time (GstElement *element, GstClockTimeDiff diff);
317 gboolean gst_element_is_indexable (GstElement *element);
318 void gst_element_set_index (GstElement *element, GstIndex *index);
319 GstIndex* gst_element_get_index (GstElement *element);
322 void gst_element_set_loop_function (GstElement *element,
323 GstElementLoopFunction loop);
324 gboolean gst_element_release_locks (GstElement *element);
325 void gst_element_yield (GstElement *element);
326 gboolean gst_element_interrupt (GstElement *element);
327 void gst_element_set_scheduler (GstElement *element, GstScheduler *sched);
328 GstScheduler* gst_element_get_scheduler (GstElement *element);
329 GstBin* gst_element_get_managing_bin (GstElement *element);
332 gboolean gst_element_add_pad (GstElement *element, GstPad *pad);
333 gboolean gst_element_remove_pad (GstElement *element, GstPad *pad);
334 GstPad * gst_element_add_ghost_pad (GstElement *element, GstPad *pad, const gchar *name);
335 void gst_element_no_more_pads (GstElement *element);
337 GstPad* gst_element_get_pad (GstElement *element, const gchar *name);
338 GstPad* gst_element_get_static_pad (GstElement *element, const gchar *name);
339 GstPad* gst_element_get_request_pad (GstElement *element, const gchar *name);
340 void gst_element_release_request_pad (GstElement *element, GstPad *pad);
342 GstIterator * gst_element_iterate_pads (GstElement * element);
344 /* event/query/format stuff */
345 G_CONST_RETURN GstEventMask*
346 gst_element_get_event_masks (GstElement *element);
347 gboolean gst_element_send_event (GstElement *element, GstEvent *event);
348 gboolean gst_element_seek (GstElement *element, GstSeekType seek_type,
350 G_CONST_RETURN GstQueryType*
351 gst_element_get_query_types (GstElement *element);
352 gboolean gst_element_query (GstElement *element, GstQueryType type,
353 GstFormat *format, gint64 *value);
354 G_CONST_RETURN GstFormat*
355 gst_element_get_formats (GstElement *element);
356 gboolean gst_element_convert (GstElement *element,
357 GstFormat src_format, gint64 src_value,
358 GstFormat *dest_format, gint64 *dest_value);
361 gchar * _gst_element_error_printf (const gchar *format, ...);
362 void gst_element_error_full (GstElement *element, GQuark domain, gint code,
363 gchar *message, gchar *debug,
364 const gchar *file, const gchar *function, gint line);
365 void gst_element_default_error (GObject *object, GstObject *orig, GError *error, gchar *debug);
366 #define gst_element_default_deep_notify gst_object_default_deep_notify
368 /* state management */
369 gboolean gst_element_is_locked_state (GstElement *element);
370 gboolean gst_element_set_locked_state (GstElement *element, gboolean locked_state);
371 gboolean gst_element_sync_state_with_parent (GstElement *element);
373 GstElementState gst_element_get_state (GstElement *element);
374 GstElementStateReturn gst_element_set_state (GstElement *element, GstElementState state);
376 void gst_element_wait_state_change (GstElement *element);
378 void gst_element_set_eos (GstElement *element);
380 /* factory management */
381 GstElementFactory* gst_element_get_factory (GstElement *element);
385 void gst_element_found_tags (GstElement *element, const GstTagList *tag_list);
386 void gst_element_found_tags_for_pad (GstElement *element, GstPad *pad, GstClockTime timestamp,
394 #define GST_TYPE_ELEMENT_FACTORY (gst_element_factory_get_type())
395 #define GST_ELEMENT_FACTORY(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_ELEMENT_FACTORY,\
397 #define GST_ELEMENT_FACTORY_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_ELEMENT_FACTORY,\
398 GstElementFactoryClass))
399 #define GST_IS_ELEMENT_FACTORY(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_ELEMENT_FACTORY))
400 #define GST_IS_ELEMENT_FACTORY_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_ELEMENT_FACTORY))
402 struct _GstElementFactory {
403 GstPluginFeature parent;
405 GType type; /* unique GType of element or 0 if not loaded */
407 GstElementDetails details;
409 GList * padtemplates;
410 guint numpadtemplates;
412 /* URI interface stuff */
414 gchar ** uri_protocols;
416 GList * interfaces; /* interfaces this element implements */
418 gpointer _gst_reserved[GST_PADDING];
421 struct _GstElementFactoryClass {
422 GstPluginFeatureClass parent_class;
424 gpointer _gst_reserved[GST_PADDING];
427 GType gst_element_factory_get_type (void);
429 gboolean gst_element_register (GstPlugin *plugin,
434 GstElementFactory * gst_element_factory_find (const gchar *name);
435 GType gst_element_factory_get_element_type (GstElementFactory *factory);
436 G_CONST_RETURN gchar * gst_element_factory_get_longname (GstElementFactory *factory);
437 G_CONST_RETURN gchar * gst_element_factory_get_klass (GstElementFactory *factory);
438 G_CONST_RETURN gchar * gst_element_factory_get_description (GstElementFactory *factory);
439 G_CONST_RETURN gchar * gst_element_factory_get_author (GstElementFactory *factory);
440 guint gst_element_factory_get_num_pad_templates (GstElementFactory *factory);
441 G_CONST_RETURN GList * gst_element_factory_get_pad_templates (GstElementFactory *factory);
442 guint gst_element_factory_get_uri_type (GstElementFactory *factory);
443 gchar ** gst_element_factory_get_uri_protocols (GstElementFactory *factory);
445 GstElement* gst_element_factory_create (GstElementFactory *factory,
447 GstElement* gst_element_factory_make (const gchar *factoryname, const gchar *name);
449 gboolean gst_element_factory_can_src_caps (GstElementFactory *factory,
450 const GstCaps *caps);
451 gboolean gst_element_factory_can_sink_caps (GstElementFactory *factory,
452 const GstCaps *caps);
454 void __gst_element_factory_add_pad_template (GstElementFactory *elementfactory,
455 GstPadTemplate *templ);
456 void __gst_element_factory_add_interface (GstElementFactory *elementfactory,
457 const gchar *interfacename);
461 #endif /* __GST_ELEMENT_H__ */