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.
38 * #GstEventTypeFlags indicate the aspects of the different #GstEventType
39 * values. You can get the type flags of a #GstEventType with the
40 * gst_event_type_get_flags() function.
43 GST_EVENT_TYPE_UPSTREAM = 1 << 0,
44 GST_EVENT_TYPE_DOWNSTREAM = 1 << 1,
45 GST_EVENT_TYPE_SERIALIZED = 1 << 2,
46 GST_EVENT_TYPE_STICKY = 1 << 3
50 * GST_EVENT_TYPE_BOTH:
52 * The same thing as #GST_EVENT_TYPE_UPSTREAM | #GST_EVENT_TYPE_DOWNSTREAM.
54 #define GST_EVENT_TYPE_BOTH \
55 (GST_EVENT_TYPE_UPSTREAM | GST_EVENT_TYPE_DOWNSTREAM)
57 #define GST_EVENT_MAX_STICKY 16
58 #define GST_EVENT_STICKY_SHIFT 8
59 #define GST_EVENT_NUM_SHIFT (GST_EVENT_STICKY_SHIFT + 4)
62 * GST_EVENT_MAKE_TYPE:
63 * @num: the event number to create
64 * @idx: the index in the sticky array
65 * @flags: the event flags
67 * when making custom event types, use this macro with the num and
70 #define GST_EVENT_MAKE_TYPE(num,idx,flags) \
71 (((num) << GST_EVENT_NUM_SHIFT) | ((idx) << GST_EVENT_STICKY_SHIFT) | (flags))
73 #define FLAG(name) GST_EVENT_TYPE_##name
75 #define GST_EVENT_STICKY_IDX_TYPE(type) (((type) >> GST_EVENT_STICKY_SHIFT) & 0xf)
76 #define GST_EVENT_STICKY_IDX(ev) GST_EVENT_STICKY_IDX_TYPE(GST_EVENT_TYPE(ev))
80 * @GST_EVENT_UNKNOWN: unknown event.
81 * @GST_EVENT_FLUSH_START: Start a flush operation. This event clears all data
82 * from the pipeline and unblock all streaming threads.
83 * @GST_EVENT_FLUSH_STOP: Stop a flush operation. This event resets the
84 * running-time of the pipeline.
85 * @GST_EVENT_CAPS: #GstCaps event. Notify the pad of a new media type.
86 * @GST_EVENT_SEGMENT: A new media segment follows in the dataflow. The
87 * segment events contains information for clipping buffers and
88 * converting buffer timestamps to running-time and
90 * @GST_EVENT_TAG: A new set of metadata tags has been found in the stream.
91 * @GST_EVENT_BUFFERSIZE: Notification of buffering requirements. Currently not
93 * @GST_EVENT_SINK_MESSAGE: An event that sinks turn into a message. Used to
94 * send messages that should be emitted in sync with
97 * @GST_EVENT_EOS: End-Of-Stream. No more data is to be expected to follow
98 * without a SEGMENT event.
99 * @GST_EVENT_QOS: A quality message. Used to indicate to upstream elements
100 * that the downstream elements should adjust their processing
102 * @GST_EVENT_SEEK: A request for a new playback position and rate.
103 * @GST_EVENT_NAVIGATION: Navigation events are usually used for communicating
104 * user requests, such as mouse or keyboard movements,
105 * to upstream elements.
106 * @GST_EVENT_LATENCY: Notification of new latency adjustment. Sinks will use
107 * the latency information to adjust their synchronisation.
109 * @GST_EVENT_STEP: A request for stepping through the media. Sinks will usually
110 * execute the step operation. Since: 0.10.24
111 * @GST_EVENT_RECONFIGURE: A request for upstream renegotiating caps and reconfiguring.
113 * @GST_EVENT_CUSTOM_UPSTREAM: Upstream custom event
114 * @GST_EVENT_CUSTOM_DOWNSTREAM: Downstream custom event that travels in the
116 * @GST_EVENT_CUSTOM_DOWNSTREAM_OOB: Custom out-of-band downstream event.
117 * @GST_EVENT_CUSTOM_BOTH: Custom upstream or downstream event.
118 * In-band when travelling downstream.
119 * @GST_EVENT_CUSTOM_BOTH_OOB: Custom upstream or downstream out-of-band event.
121 * #GstEventType lists the standard event types that can be sent in a pipeline.
123 * The custom event types can be used for private messages between elements
124 * that can't be expressed using normal
125 * GStreamer buffer passing semantics. Custom events carry an arbitrary
127 * Specific custom events are distinguished by the name of the structure.
129 /* NOTE: keep in sync with quark registration in gstevent.c */
131 GST_EVENT_UNKNOWN = GST_EVENT_MAKE_TYPE (0, 0, 0),
132 /* bidirectional events */
133 GST_EVENT_FLUSH_START = GST_EVENT_MAKE_TYPE (1, 0, FLAG(BOTH)),
134 GST_EVENT_FLUSH_STOP = GST_EVENT_MAKE_TYPE (2, 0, FLAG(BOTH) | FLAG(SERIALIZED)),
135 /* downstream serialized events */
136 GST_EVENT_CAPS = GST_EVENT_MAKE_TYPE (5, 1, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
137 GST_EVENT_SEGMENT = GST_EVENT_MAKE_TYPE (6, 2, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
138 GST_EVENT_TAG = GST_EVENT_MAKE_TYPE (7, 3, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
139 GST_EVENT_BUFFERSIZE = GST_EVENT_MAKE_TYPE (8, 4, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
140 GST_EVENT_SINK_MESSAGE = GST_EVENT_MAKE_TYPE (9, 5, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
141 GST_EVENT_EOS = GST_EVENT_MAKE_TYPE (10, 6, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
143 /* upstream events */
144 GST_EVENT_QOS = GST_EVENT_MAKE_TYPE (15, 0, FLAG(UPSTREAM)),
145 GST_EVENT_SEEK = GST_EVENT_MAKE_TYPE (16, 0, FLAG(UPSTREAM)),
146 GST_EVENT_NAVIGATION = GST_EVENT_MAKE_TYPE (17, 0, FLAG(UPSTREAM)),
147 GST_EVENT_LATENCY = GST_EVENT_MAKE_TYPE (18, 0, FLAG(UPSTREAM)),
148 GST_EVENT_STEP = GST_EVENT_MAKE_TYPE (19, 0, FLAG(UPSTREAM)),
149 GST_EVENT_RECONFIGURE = GST_EVENT_MAKE_TYPE (20, 0, FLAG(UPSTREAM)),
151 /* custom events start here */
152 GST_EVENT_CUSTOM_UPSTREAM = GST_EVENT_MAKE_TYPE (32, 0, FLAG(UPSTREAM)),
153 GST_EVENT_CUSTOM_DOWNSTREAM = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)),
154 GST_EVENT_CUSTOM_DOWNSTREAM_OOB = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM)),
155 GST_EVENT_CUSTOM_BOTH = GST_EVENT_MAKE_TYPE (32, 0, FLAG(BOTH) | FLAG(SERIALIZED)),
156 GST_EVENT_CUSTOM_BOTH_OOB = GST_EVENT_MAKE_TYPE (32, 0, FLAG(BOTH))
160 #include <gst/gstminiobject.h>
161 #include <gst/gstformat.h>
162 #include <gst/gstobject.h>
163 #include <gst/gstclock.h>
164 #include <gst/gststructure.h>
165 #include <gst/gsttaglist.h>
166 #include <gst/gstsegment.h>
167 #include <gst/gstsegment.h>
168 #include <gst/gstmessage.h>
172 extern GType _gst_event_type;
174 #define GST_TYPE_EVENT (_gst_event_type)
175 #define GST_IS_EVENT(obj) (GST_IS_MINI_OBJECT_TYPE (obj, GST_TYPE_EVENT))
176 #define GST_EVENT_CAST(obj) ((GstEvent *)(obj))
177 #define GST_EVENT(obj) (GST_EVENT_CAST(obj))
180 * GST_EVENT_TRACE_NAME:
182 * The name used for memory allocation tracing
184 #define GST_EVENT_TRACE_NAME "GstEvent"
188 * @event: the event to query
190 * Get the #GstEventType of the event.
192 #define GST_EVENT_TYPE(event) (GST_EVENT_CAST(event)->type)
195 * GST_EVENT_TYPE_NAME:
196 * @event: the event to query
198 * Get a constant string representation of the #GstEventType of the event.
200 #define GST_EVENT_TYPE_NAME(event) (gst_event_type_get_name(GST_EVENT_TYPE(event)))
203 * GST_EVENT_TIMESTAMP:
204 * @event: the event to query
206 * Get the #GstClockTime timestamp of the event. This is the time when the event
209 #define GST_EVENT_TIMESTAMP(event) (GST_EVENT_CAST(event)->timestamp)
213 * @event: the event to query
215 * The sequence number of @event.
217 #define GST_EVENT_SEQNUM(event) (GST_EVENT_CAST(event)->seqnum)
220 * GST_EVENT_IS_UPSTREAM:
221 * @ev: the event to query
223 * Check if an event can travel upstream.
225 #define GST_EVENT_IS_UPSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_UPSTREAM)
227 * GST_EVENT_IS_DOWNSTREAM:
228 * @ev: the event to query
230 * Check if an event can travel downstream.
232 #define GST_EVENT_IS_DOWNSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_DOWNSTREAM)
234 * GST_EVENT_IS_SERIALIZED:
235 * @ev: the event to query
237 * Check if an event is serialized with the data stream.
239 #define GST_EVENT_IS_SERIALIZED(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_SERIALIZED)
241 * GST_EVENT_IS_STICKY:
242 * @ev: the event to query
244 * Check if an event is sticky on the pads.
246 #define GST_EVENT_IS_STICKY(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_STICKY)
249 * gst_event_is_writable:
252 * Tests if you can safely write data into a event's structure or validly
253 * modify the seqnum and timestamp field.
255 #define gst_event_is_writable(ev) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (ev))
257 * gst_event_make_writable:
258 * @ev: (transfer full): a #GstEvent
260 * Makes a writable event from the given event. If the source event is
261 * already writable, this will simply return the same event. A copy will
262 * otherwise be made using gst_event_copy().
264 * Returns: (transfer full): a writable event which may or may not be the
267 #define gst_event_make_writable(ev) GST_EVENT_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (ev)))
270 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
272 * @new_event: (allow-none) (transfer none): pointer to a #GstEvent that will
273 * replace the event pointed to by @old_event.
275 * Modifies a pointer to a #GstEvent to point to a different #GstEvent. The
276 * modification is done atomically (so this is useful for ensuring thread safety
277 * in some cases), and the reference counts are updated appropriately (the old
278 * event is unreffed, the new one is reffed).
280 * Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
282 * Returns: TRUE if @new_event was different from @old_event
284 #define gst_event_replace(old_event,new_event) \
285 gst_mini_object_replace ((GstMiniObject **)(old_event), GST_MINI_OBJECT_CAST (new_event))
288 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
291 * Atomically replace the #GstEvent pointed to by @old_event with NULL and
292 * return the original event.
294 * Returns: the #GstEvent that was in @old_event
296 #define gst_event_steal(old_event) \
297 GST_EVENT_CAST (gst_mini_object_steal ((GstMiniObject **)(old_event)))
300 * @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
302 * @new_event: (allow-none) (transfer full): pointer to a #GstEvent that will
303 * replace the event pointed to by @old_event.
305 * Modifies a pointer to a #GstEvent to point to a different #GstEvent. This
306 * function is similar to gst_event_replace() except that it takes ownership of
309 * Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
311 * Returns: TRUE if @new_event was different from @old_event
313 #define gst_event_take(old_event,new_event) \
314 gst_mini_object_take ((GstMiniObject **)(old_event), GST_MINI_OBJECT_CAST (new_event))
318 * @GST_QOS_TYPE_OVERFLOW: The QoS event type that is produced when downstream
319 * elements are producing data too quickly and the element can't keep up
320 * processing the data. Upstream should reduce their processing rate. This
321 * type is also used when buffers arrive early or in time.
322 * @GST_QOS_TYPE_UNDERFLOW: The QoS event type that is produced when downstream
323 * elements are producing data too slowly and need to speed up their processing
325 * @GST_QOS_TYPE_THROTTLE: The QoS event type that is produced when the
326 * application enabled throttling to limit the datarate.
328 * The different types of QoS events that can be given to the
329 * gst_event_new_qos() method.
334 GST_QOS_TYPE_OVERFLOW = 0,
335 GST_QOS_TYPE_UNDERFLOW = 1,
336 GST_QOS_TYPE_THROTTLE = 2
341 * @mini_object: the parent structure
342 * @type: the #GstEventType of the event
343 * @timestamp: the timestamp of the event
344 * @seqnum: the sequence number of the event
349 GstMiniObject mini_object;
351 /*< public >*/ /* with COW */
357 const gchar* gst_event_type_get_name (GstEventType type);
358 GQuark gst_event_type_to_quark (GstEventType type);
360 gst_event_type_get_flags (GstEventType type);
366 * @event: The event to refcount
368 * Increase the refcount of this event.
370 * Returns: (transfer full): @event (for convenience when doing assignments)
372 #ifdef _FOOL_GTK_DOC_
373 G_INLINE_FUNC GstEvent * gst_event_ref (GstEvent * event);
376 static inline GstEvent *
377 gst_event_ref (GstEvent * event)
379 return (GstEvent *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (event));
384 * @event: (transfer full): the event to refcount
386 * Decrease the refcount of an event, freeing it if the refcount reaches 0.
388 #ifdef _FOOL_GTK_DOC_
389 G_INLINE_FUNC void gst_event_unref (GstEvent * event);
393 gst_event_unref (GstEvent * event)
395 gst_mini_object_unref (GST_MINI_OBJECT_CAST (event));
401 * @event: The event to copy
403 * Copy the event using the event specific copy function.
405 * Returns: (transfer full): the new event
407 #ifdef _FOOL_GTK_DOC_
408 G_INLINE_FUNC GstEvent * gst_event_copy (const GstEvent * event);
411 static inline GstEvent *
412 gst_event_copy (const GstEvent * event)
414 return GST_EVENT_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (event)));
417 GType gst_event_get_type (void);
420 GstEvent* gst_event_new_custom (GstEventType type, GstStructure *structure);
423 gst_event_get_structure (GstEvent *event);
424 GstStructure * gst_event_writable_structure (GstEvent *event);
426 gboolean gst_event_has_name (GstEvent *event, const gchar *name);
428 /* identifiers for events and messages */
429 guint32 gst_event_get_seqnum (GstEvent *event);
430 void gst_event_set_seqnum (GstEvent *event, guint32 seqnum);
433 GstEvent * gst_event_new_flush_start (void);
435 GstEvent * gst_event_new_flush_stop (gboolean reset_time);
436 void gst_event_parse_flush_stop (GstEvent *event, gboolean *reset_time);
439 GstEvent * gst_event_new_eos (void);
442 GstEvent * gst_event_new_caps (GstCaps *caps);
443 void gst_event_parse_caps (GstEvent *event, GstCaps **caps);
446 GstEvent* gst_event_new_segment (GstSegment *segment);
447 void gst_event_parse_segment (GstEvent *event, const GstSegment **segment);
448 void gst_event_copy_segment (GstEvent *event, GstSegment *segment);
451 GstEvent* gst_event_new_tag (GstTagList *taglist);
452 void gst_event_parse_tag (GstEvent *event, GstTagList **taglist);
455 GstEvent * gst_event_new_buffer_size (GstFormat format, gint64 minsize, gint64 maxsize,
457 void gst_event_parse_buffer_size (GstEvent *event, GstFormat *format, gint64 *minsize,
458 gint64 *maxsize, gboolean *async);
461 GstEvent* gst_event_new_sink_message (GstMessage *msg);
462 void gst_event_parse_sink_message (GstEvent *event, GstMessage **msg);
465 GstEvent* gst_event_new_qos (GstQOSType type, gdouble proportion,
466 GstClockTimeDiff diff, GstClockTime timestamp);
467 void gst_event_parse_qos (GstEvent *event, GstQOSType *type,
468 gdouble *proportion, GstClockTimeDiff *diff,
469 GstClockTime *timestamp);
471 GstEvent* gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
472 GstSeekType start_type, gint64 start,
473 GstSeekType stop_type, gint64 stop);
474 void gst_event_parse_seek (GstEvent *event, gdouble *rate, GstFormat *format,
476 GstSeekType *start_type, gint64 *start,
477 GstSeekType *stop_type, gint64 *stop);
479 /* navigation event */
480 GstEvent* gst_event_new_navigation (GstStructure *structure);
483 GstEvent* gst_event_new_latency (GstClockTime latency);
484 void gst_event_parse_latency (GstEvent *event, GstClockTime *latency);
487 GstEvent* gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
488 gboolean flush, gboolean intermediate);
489 void gst_event_parse_step (GstEvent *event, GstFormat *format, guint64 *amount,
490 gdouble *rate, gboolean *flush, gboolean *intermediate);
492 /* renegotiate event */
493 GstEvent* gst_event_new_reconfigure (void);
497 #endif /* __GST_EVENT_H__ */