2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wim.taymans@chello.be>
4 * 2005 Wim Taymans <wim@fluendo.com>
6 * gstevent.h: Header for GstEvent subsystem
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
25 #ifndef __GST_EVENT_H__
26 #define __GST_EVENT_H__
28 typedef struct _GstEvent GstEvent;
32 * @GST_EVENT_TYPE_UPSTREAM: Set if the event can travel upstream.
33 * @GST_EVENT_TYPE_DOWNSTREAM: Set if the event can travel downstream.
34 * @GST_EVENT_TYPE_SERIALIZED: Set if the event should be serialized with data
36 * @GST_EVENT_TYPE_STICKY: Set if the event is sticky on the pads.
37 * @GST_EVENT_TYPE_STICKY_MULTI: Multiple sticky events can be on a pad, each
38 * identified by the event name.
40 * #GstEventTypeFlags indicate the aspects of the different #GstEventType
41 * values. You can get the type flags of a #GstEventType with the
42 * gst_event_type_get_flags() function.
45 GST_EVENT_TYPE_UPSTREAM = 1 << 0,
46 GST_EVENT_TYPE_DOWNSTREAM = 1 << 1,
47 GST_EVENT_TYPE_SERIALIZED = 1 << 2,
48 GST_EVENT_TYPE_STICKY = 1 << 3,
49 GST_EVENT_TYPE_STICKY_MULTI = 1 << 4
53 * GST_EVENT_TYPE_BOTH:
55 * The same thing as #GST_EVENT_TYPE_UPSTREAM | #GST_EVENT_TYPE_DOWNSTREAM.
57 #define GST_EVENT_TYPE_BOTH \
58 (GST_EVENT_TYPE_UPSTREAM | GST_EVENT_TYPE_DOWNSTREAM)
60 #define GST_EVENT_NUM_SHIFT (8)
63 * GST_EVENT_MAKE_TYPE:
64 * @num: the event number to create
65 * @idx: the index in the sticky array
66 * @flags: the event flags
68 * when making custom event types, use this macro with the num and
71 #define GST_EVENT_MAKE_TYPE(num,flags) \
72 (((num) << GST_EVENT_NUM_SHIFT) | (flags))
74 #define FLAG(name) GST_EVENT_TYPE_##name
78 * @GST_EVENT_UNKNOWN: unknown event.
79 * @GST_EVENT_FLUSH_START: Start a flush operation. This event clears all data
80 * from the pipeline and unblock all streaming threads.
81 * @GST_EVENT_FLUSH_STOP: Stop a flush operation. This event resets the
82 * running-time of the pipeline.
83 * @GST_EVENT_STREAM_START: Event to mark the start of a new stream. Sent before any
84 * other serialized event and only sent at the start of a new stream,
85 * not after flushing seeks.
86 * @GST_EVENT_CAPS: #GstCaps event. Notify the pad of a new media type.
87 * @GST_EVENT_STREAM_CONFIG: contains configuration information for the stream,
88 * for example stream-headers and codec-data.
89 * @GST_EVENT_SEGMENT: A new media segment follows in the dataflow. The
90 * segment events contains information for clipping buffers and
91 * converting buffer timestamps to running-time and
93 * @GST_EVENT_TAG: A new set of metadata tags has been found in the stream.
94 * @GST_EVENT_BUFFERSIZE: Notification of buffering requirements. Currently not
96 * @GST_EVENT_SINK_MESSAGE: An event that sinks turn into a message. Used to
97 * send messages that should be emitted in sync with
100 * @GST_EVENT_EOS: End-Of-Stream. No more data is to be expected to follow
101 * without a SEGMENT event.
102 * @GST_EVENT_SEGMENT_DONE: (unimplemented) Marks the end of a segment playback.
103 * @GST_EVENT_GAP: (unimplemented) Marks a gap in the datastream.
104 * @GST_EVENT_QOS: A quality message. Used to indicate to upstream elements
105 * that the downstream elements should adjust their processing
107 * @GST_EVENT_SEEK: A request for a new playback position and rate.
108 * @GST_EVENT_NAVIGATION: Navigation events are usually used for communicating
109 * user requests, such as mouse or keyboard movements,
110 * to upstream elements.
111 * @GST_EVENT_LATENCY: Notification of new latency adjustment. Sinks will use
112 * the latency information to adjust their synchronisation.
114 * @GST_EVENT_STEP: A request for stepping through the media. Sinks will usually
115 * execute the step operation. Since: 0.10.24
116 * @GST_EVENT_RECONFIGURE: A request for upstream renegotiating caps and reconfiguring.
118 * @GST_EVENT_CUSTOM_UPSTREAM: Upstream custom event
119 * @GST_EVENT_CUSTOM_DOWNSTREAM: Downstream custom event that travels in the
121 * @GST_EVENT_CUSTOM_DOWNSTREAM_OOB: Custom out-of-band downstream event.
122 * @GST_EVENT_CUSTOM_DOWNSTREAM_STICKY: Custom sticky downstream event.
123 * @GST_EVENT_CUSTOM_BOTH: Custom upstream or downstream event.
124 * In-band when travelling downstream.
125 * @GST_EVENT_CUSTOM_BOTH_OOB: Custom upstream or downstream out-of-band event.
127 * #GstEventType lists the standard event types that can be sent in a pipeline.
129 * The custom event types can be used for private messages between elements
130 * that can't be expressed using normal
131 * GStreamer buffer passing semantics. Custom events carry an arbitrary
133 * Specific custom events are distinguished by the name of the structure.
135 /* NOTE: keep in sync with quark registration in gstevent.c */
137 GST_EVENT_UNKNOWN = GST_EVENT_MAKE_TYPE (0, 0),
139 /* bidirectional events */
140 GST_EVENT_FLUSH_START = GST_EVENT_MAKE_TYPE (10, FLAG(BOTH)),
141 GST_EVENT_FLUSH_STOP = GST_EVENT_MAKE_TYPE (20, FLAG(BOTH) | FLAG(SERIALIZED)),
143 /* downstream serialized events */
144 GST_EVENT_STREAM_START = GST_EVENT_MAKE_TYPE (40, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
145 GST_EVENT_CAPS = GST_EVENT_MAKE_TYPE (50, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
146 GST_EVENT_STREAM_CONFIG = GST_EVENT_MAKE_TYPE (60, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
147 GST_EVENT_SEGMENT = GST_EVENT_MAKE_TYPE (70, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
148 GST_EVENT_TAG = GST_EVENT_MAKE_TYPE (80, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY) | FLAG(STICKY_MULTI)),
149 GST_EVENT_BUFFERSIZE = GST_EVENT_MAKE_TYPE (90, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
150 GST_EVENT_SINK_MESSAGE = GST_EVENT_MAKE_TYPE (100, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY) | FLAG(STICKY_MULTI)),
151 GST_EVENT_EOS = GST_EVENT_MAKE_TYPE (110, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
153 /* non-sticky downstream serialized */
154 GST_EVENT_SEGMENT_DONE = GST_EVENT_MAKE_TYPE (150, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)),
155 GST_EVENT_GAP = GST_EVENT_MAKE_TYPE (160, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)),
157 /* upstream events */
158 GST_EVENT_QOS = GST_EVENT_MAKE_TYPE (190, FLAG(UPSTREAM)),
159 GST_EVENT_SEEK = GST_EVENT_MAKE_TYPE (200, FLAG(UPSTREAM)),
160 GST_EVENT_NAVIGATION = GST_EVENT_MAKE_TYPE (210, FLAG(UPSTREAM)),
161 GST_EVENT_LATENCY = GST_EVENT_MAKE_TYPE (220, FLAG(UPSTREAM)),
162 GST_EVENT_STEP = GST_EVENT_MAKE_TYPE (230, FLAG(UPSTREAM)),
163 GST_EVENT_RECONFIGURE = GST_EVENT_MAKE_TYPE (240, FLAG(UPSTREAM)),
165 /* custom events start here */
166 GST_EVENT_CUSTOM_UPSTREAM = GST_EVENT_MAKE_TYPE (270, FLAG(UPSTREAM)),
167 GST_EVENT_CUSTOM_DOWNSTREAM = GST_EVENT_MAKE_TYPE (280, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)),
168 GST_EVENT_CUSTOM_DOWNSTREAM_OOB = GST_EVENT_MAKE_TYPE (290, FLAG(DOWNSTREAM)),
169 GST_EVENT_CUSTOM_DOWNSTREAM_STICKY = GST_EVENT_MAKE_TYPE (300, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY) | FLAG(STICKY_MULTI)),
170 GST_EVENT_CUSTOM_BOTH = GST_EVENT_MAKE_TYPE (310, FLAG(BOTH) | FLAG(SERIALIZED)),
171 GST_EVENT_CUSTOM_BOTH_OOB = GST_EVENT_MAKE_TYPE (320, FLAG(BOTH))
175 #include <gst/gstminiobject.h>
176 #include <gst/gstformat.h>
177 #include <gst/gstobject.h>
178 #include <gst/gstclock.h>
179 #include <gst/gststructure.h>
180 #include <gst/gsttaglist.h>
181 #include <gst/gstsegment.h>
182 #include <gst/gstsegment.h>
183 #include <gst/gstmessage.h>
187 GST_EXPORT GType _gst_event_type;
189 #define GST_TYPE_EVENT (_gst_event_type)
190 #define GST_IS_EVENT(obj) (GST_IS_MINI_OBJECT_TYPE (obj, GST_TYPE_EVENT))
191 #define GST_EVENT_CAST(obj) ((GstEvent *)(obj))
192 #define GST_EVENT(obj) (GST_EVENT_CAST(obj))
195 * GST_EVENT_TRACE_NAME:
197 * The name used for memory allocation tracing
199 #define GST_EVENT_TRACE_NAME "GstEvent"
203 * @event: the event to query
205 * Get the #GstEventType of the event.
207 #define GST_EVENT_TYPE(event) (GST_EVENT_CAST(event)->type)
210 * GST_EVENT_TYPE_NAME:
211 * @event: the event to query
213 * Get a constant string representation of the #GstEventType of the event.
215 #define GST_EVENT_TYPE_NAME(event) (gst_event_type_get_name(GST_EVENT_TYPE(event)))
218 * GST_EVENT_TIMESTAMP:
219 * @event: the event to query
221 * Get the #GstClockTime timestamp of the event. This is the time when the event
224 #define GST_EVENT_TIMESTAMP(event) (GST_EVENT_CAST(event)->timestamp)
228 * @event: the event to query
230 * The sequence number of @event.
232 #define GST_EVENT_SEQNUM(event) (GST_EVENT_CAST(event)->seqnum)
235 * GST_EVENT_IS_UPSTREAM:
236 * @ev: the event to query
238 * Check if an event can travel upstream.
240 #define GST_EVENT_IS_UPSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_UPSTREAM)
242 * GST_EVENT_IS_DOWNSTREAM:
243 * @ev: the event to query
245 * Check if an event can travel downstream.
247 #define GST_EVENT_IS_DOWNSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_DOWNSTREAM)
249 * GST_EVENT_IS_SERIALIZED:
250 * @ev: the event to query
252 * Check if an event is serialized with the data stream.
254 #define GST_EVENT_IS_SERIALIZED(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_SERIALIZED)
256 * GST_EVENT_IS_STICKY:
257 * @ev: the event to query
259 * Check if an event is sticky on the pads.
261 #define GST_EVENT_IS_STICKY(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_STICKY)
264 * gst_event_is_writable:
267 * Tests if you can safely write data into a event's structure or validly
268 * modify the seqnum and timestamp field.
270 #define gst_event_is_writable(ev) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (ev))
272 * gst_event_make_writable:
273 * @ev: (transfer full): a #GstEvent
275 * Makes a writable event from the given event. If the source event is
276 * already writable, this will simply return the same event. A copy will
277 * otherwise be made using gst_event_copy().
279 * Returns: (transfer full): a writable event which may or may not be the
282 #define gst_event_make_writable(ev) GST_EVENT_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (ev)))
285 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
287 * @new_event: (allow-none) (transfer none): pointer to a #GstEvent that will
288 * replace the event pointed to by @old_event.
290 * Modifies a pointer to a #GstEvent to point to a different #GstEvent. The
291 * modification is done atomically (so this is useful for ensuring thread safety
292 * in some cases), and the reference counts are updated appropriately (the old
293 * event is unreffed, the new one is reffed).
295 * Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
297 * Returns: TRUE if @new_event was different from @old_event
299 #ifdef _FOOL_GTK_DOC_
300 G_INLINE_FUNC gboolean gst_event_replace (GstEvent **old_event, GstEvent *new_event);
303 static inline gboolean
304 gst_event_replace (GstEvent **old_event, GstEvent *new_event)
306 return gst_mini_object_replace ((GstMiniObject **) old_event, (GstMiniObject *) new_event);
311 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
314 * Atomically replace the #GstEvent pointed to by @old_event with NULL and
315 * return the original event.
317 * Returns: the #GstEvent that was in @old_event
319 #ifdef _FOOL_GTK_DOC_
320 G_INLINE_FUNC GstEvent * gst_event_steal (GstEvent **old_event);
323 static inline GstEvent *
324 gst_event_steal (GstEvent **old_event)
326 return GST_EVENT_CAST (gst_mini_object_steal ((GstMiniObject **) old_event));
331 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
333 * @new_event: (allow-none) (transfer full): pointer to a #GstEvent that will
334 * replace the event pointed to by @old_event.
336 * Modifies a pointer to a #GstEvent to point to a different #GstEvent. This
337 * function is similar to gst_event_replace() except that it takes ownership of
340 * Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
342 * Returns: TRUE if @new_event was different from @old_event
344 #ifdef _FOOL_GTK_DOC_
345 G_INLINE_FUNC gboolean gst_event_take (GstEvent **old_event, GstEvent *new_event);
348 static inline gboolean
349 gst_event_take (GstEvent **old_event, GstEvent *new_event)
351 return gst_mini_object_take ((GstMiniObject **) old_event, (GstMiniObject *) new_event);
356 * @GST_QOS_TYPE_OVERFLOW: The QoS event type that is produced when downstream
357 * elements are producing data too quickly and the element can't keep up
358 * processing the data. Upstream should reduce their processing rate. This
359 * type is also used when buffers arrive early or in time.
360 * @GST_QOS_TYPE_UNDERFLOW: The QoS event type that is produced when downstream
361 * elements are producing data too slowly and need to speed up their processing
363 * @GST_QOS_TYPE_THROTTLE: The QoS event type that is produced when the
364 * application enabled throttling to limit the datarate.
366 * The different types of QoS events that can be given to the
367 * gst_event_new_qos() method.
372 GST_QOS_TYPE_OVERFLOW = 0,
373 GST_QOS_TYPE_UNDERFLOW = 1,
374 GST_QOS_TYPE_THROTTLE = 2
378 * GstStreamConfigFlags:
379 * @GST_STREAM_CONFIG_FLAG_NONE: no flags set
381 * GstStreamConfigFlags are flags passed with the stream config event, see
382 * gst_event_new_stream_config().
385 GST_STREAM_CONFIG_FLAG_NONE = 0
386 } GstStreamConfigFlags;
390 * @mini_object: the parent structure
391 * @type: the #GstEventType of the event
392 * @timestamp: the timestamp of the event
393 * @seqnum: the sequence number of the event
398 GstMiniObject mini_object;
400 /*< public >*/ /* with COW */
406 const gchar* gst_event_type_get_name (GstEventType type);
407 GQuark gst_event_type_to_quark (GstEventType type);
409 gst_event_type_get_flags (GstEventType type);
415 * @event: The event to refcount
417 * Increase the refcount of this event.
419 * Returns: (transfer full): @event (for convenience when doing assignments)
421 #ifdef _FOOL_GTK_DOC_
422 G_INLINE_FUNC GstEvent * gst_event_ref (GstEvent * event);
425 static inline GstEvent *
426 gst_event_ref (GstEvent * event)
428 return (GstEvent *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (event));
433 * @event: (transfer full): the event to refcount
435 * Decrease the refcount of an event, freeing it if the refcount reaches 0.
437 #ifdef _FOOL_GTK_DOC_
438 G_INLINE_FUNC void gst_event_unref (GstEvent * event);
442 gst_event_unref (GstEvent * event)
444 gst_mini_object_unref (GST_MINI_OBJECT_CAST (event));
450 * @event: The event to copy
452 * Copy the event using the event specific copy function.
454 * Returns: (transfer full): the new event
456 #ifdef _FOOL_GTK_DOC_
457 G_INLINE_FUNC GstEvent * gst_event_copy (const GstEvent * event);
460 static inline GstEvent *
461 gst_event_copy (const GstEvent * event)
463 return GST_EVENT_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (event)));
466 GType gst_event_get_type (void);
469 GstEvent* gst_event_new_custom (GstEventType type, GstStructure *structure) G_GNUC_MALLOC;
472 gst_event_get_structure (GstEvent *event);
473 GstStructure * gst_event_writable_structure (GstEvent *event);
475 gboolean gst_event_has_name (GstEvent *event, const gchar *name);
477 /* identifiers for events and messages */
478 guint32 gst_event_get_seqnum (GstEvent *event);
479 void gst_event_set_seqnum (GstEvent *event, guint32 seqnum);
481 /* Stream start event */
482 GstEvent * gst_event_new_stream_start (void) G_GNUC_MALLOC;
485 GstEvent * gst_event_new_flush_start (void) G_GNUC_MALLOC;
487 GstEvent * gst_event_new_flush_stop (gboolean reset_time) G_GNUC_MALLOC;
488 void gst_event_parse_flush_stop (GstEvent *event, gboolean *reset_time);
491 GstEvent * gst_event_new_eos (void) G_GNUC_MALLOC;
494 GstEvent * gst_event_new_gap (GstClockTime ts,
495 GstClockTime duration) G_GNUC_MALLOC;
497 void gst_event_parse_gap (GstEvent * event,
498 GstClockTime * timestamp,
499 GstClockTime * duration);
502 GstEvent * gst_event_new_caps (GstCaps *caps) G_GNUC_MALLOC;
503 void gst_event_parse_caps (GstEvent *event, GstCaps **caps);
506 GstEvent * gst_event_new_stream_config (GstStreamConfigFlags flags) G_GNUC_MALLOC;
508 void gst_event_parse_stream_config (GstEvent * event, GstStreamConfigFlags * flags);
511 void gst_event_set_stream_config_codec_data (GstEvent * event, GstBuffer * buf);
513 void gst_event_parse_stream_config_codec_data (GstEvent * event, GstBuffer ** buf);
516 void gst_event_add_stream_config_header (GstEvent * event, GstBuffer * buf);
518 guint gst_event_get_n_stream_config_headers (GstEvent * event);
520 void gst_event_parse_nth_stream_config_header (GstEvent * event, guint index, GstBuffer ** buf);
523 GstEvent* gst_event_new_segment (const GstSegment *segment) G_GNUC_MALLOC;
524 void gst_event_parse_segment (GstEvent *event, const GstSegment **segment);
525 void gst_event_copy_segment (GstEvent *event, GstSegment *segment);
528 GstEvent* gst_event_new_tag (GstTagList *taglist) G_GNUC_MALLOC;
529 void gst_event_parse_tag (GstEvent *event, GstTagList **taglist);
532 GstEvent * gst_event_new_buffer_size (GstFormat format, gint64 minsize, gint64 maxsize,
533 gboolean async) G_GNUC_MALLOC;
534 void gst_event_parse_buffer_size (GstEvent *event, GstFormat *format, gint64 *minsize,
535 gint64 *maxsize, gboolean *async);
538 GstEvent* gst_event_new_sink_message (GstMessage *msg) G_GNUC_MALLOC;
539 void gst_event_parse_sink_message (GstEvent *event, GstMessage **msg);
542 GstEvent* gst_event_new_qos (GstQOSType type, gdouble proportion,
543 GstClockTimeDiff diff, GstClockTime timestamp) G_GNUC_MALLOC;
544 void gst_event_parse_qos (GstEvent *event, GstQOSType *type,
545 gdouble *proportion, GstClockTimeDiff *diff,
546 GstClockTime *timestamp);
548 GstEvent* gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
549 GstSeekType start_type, gint64 start,
550 GstSeekType stop_type, gint64 stop) G_GNUC_MALLOC;
551 void gst_event_parse_seek (GstEvent *event, gdouble *rate, GstFormat *format,
553 GstSeekType *start_type, gint64 *start,
554 GstSeekType *stop_type, gint64 *stop);
556 /* navigation event */
557 GstEvent* gst_event_new_navigation (GstStructure *structure) G_GNUC_MALLOC;
560 GstEvent* gst_event_new_latency (GstClockTime latency) G_GNUC_MALLOC;
561 void gst_event_parse_latency (GstEvent *event, GstClockTime *latency);
564 GstEvent* gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
565 gboolean flush, gboolean intermediate) G_GNUC_MALLOC;
566 void gst_event_parse_step (GstEvent *event, GstFormat *format, guint64 *amount,
567 gdouble *rate, gboolean *flush, gboolean *intermediate);
569 /* renegotiate event */
570 GstEvent* gst_event_new_reconfigure (void) G_GNUC_MALLOC;
574 #endif /* __GST_EVENT_H__ */