gstreamer/gst/gstevent.h
2011-11-02 08:59:44 +01:00

505 lines
19 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wim.taymans@chello.be>
* 2005 Wim Taymans <wim@fluendo.com>
*
* gstevent.h: Header for GstEvent subsystem
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_EVENT_H__
#define __GST_EVENT_H__
typedef struct _GstEvent GstEvent;
/**
* GstEventTypeFlags:
* @GST_EVENT_TYPE_UPSTREAM: Set if the event can travel upstream.
* @GST_EVENT_TYPE_DOWNSTREAM: Set if the event can travel downstream.
* @GST_EVENT_TYPE_SERIALIZED: Set if the event should be serialized with data
* flow.
* @GST_EVENT_TYPE_STICKY: Set if the event is sticky on the pads.
*
* #GstEventTypeFlags indicate the aspects of the different #GstEventType
* values. You can get the type flags of a #GstEventType with the
* gst_event_type_get_flags() function.
*/
typedef enum {
GST_EVENT_TYPE_UPSTREAM = 1 << 0,
GST_EVENT_TYPE_DOWNSTREAM = 1 << 1,
GST_EVENT_TYPE_SERIALIZED = 1 << 2,
GST_EVENT_TYPE_STICKY = 1 << 3
} GstEventTypeFlags;
/**
* GST_EVENT_TYPE_BOTH:
*
* The same thing as #GST_EVENT_TYPE_UPSTREAM | #GST_EVENT_TYPE_DOWNSTREAM.
*/
#define GST_EVENT_TYPE_BOTH \
(GST_EVENT_TYPE_UPSTREAM | GST_EVENT_TYPE_DOWNSTREAM)
#define GST_EVENT_MAX_STICKY 16
#define GST_EVENT_STICKY_SHIFT 8
#define GST_EVENT_NUM_SHIFT (GST_EVENT_STICKY_SHIFT + 4)
/**
* GST_EVENT_MAKE_TYPE:
* @num: the event number to create
* @idx: the index in the sticky array
* @flags: the event flags
*
* when making custom event types, use this macro with the num and
* the given flags
*/
#define GST_EVENT_MAKE_TYPE(num,idx,flags) \
(((num) << GST_EVENT_NUM_SHIFT) | ((idx) << GST_EVENT_STICKY_SHIFT) | (flags))
#define FLAG(name) GST_EVENT_TYPE_##name
#define GST_EVENT_STICKY_IDX_TYPE(type) (((type) >> GST_EVENT_STICKY_SHIFT) & 0xf)
#define GST_EVENT_STICKY_IDX(ev) GST_EVENT_STICKY_IDX_TYPE(GST_EVENT_TYPE(ev))
/**
* GstEventType:
* @GST_EVENT_UNKNOWN: unknown event.
* @GST_EVENT_FLUSH_START: Start a flush operation. This event clears all data
* from the pipeline and unblock all streaming threads.
* @GST_EVENT_FLUSH_STOP: Stop a flush operation. This event resets the
* running-time of the pipeline.
* @GST_EVENT_CAPS: #GstCaps event. Notify the pad of a new media type.
* @GST_EVENT_SEGMENT: A new media segment follows in the dataflow. The
* segment events contains information for clipping buffers and
* converting buffer timestamps to running-time and
* stream-time.
* @GST_EVENT_TAG: A new set of metadata tags has been found in the stream.
* @GST_EVENT_BUFFERSIZE: Notification of buffering requirements. Currently not
* used yet.
* @GST_EVENT_SINK_MESSAGE: An event that sinks turn into a message. Used to
* send messages that should be emitted in sync with
* rendering.
* Since: 0.10.26
* @GST_EVENT_EOS: End-Of-Stream. No more data is to be expected to follow
* without a SEGMENT event.
* @GST_EVENT_QOS: A quality message. Used to indicate to upstream elements
* that the downstream elements should adjust their processing
* rate.
* @GST_EVENT_SEEK: A request for a new playback position and rate.
* @GST_EVENT_NAVIGATION: Navigation events are usually used for communicating
* user requests, such as mouse or keyboard movements,
* to upstream elements.
* @GST_EVENT_LATENCY: Notification of new latency adjustment. Sinks will use
* the latency information to adjust their synchronisation.
* Since: 0.10.12
* @GST_EVENT_STEP: A request for stepping through the media. Sinks will usually
* execute the step operation. Since: 0.10.24
* @GST_EVENT_RECONFIGURE: A request for upstream renegotiating caps and reconfiguring.
* Since: 0.11.0
* @GST_EVENT_CUSTOM_UPSTREAM: Upstream custom event
* @GST_EVENT_CUSTOM_DOWNSTREAM: Downstream custom event that travels in the
* data flow.
* @GST_EVENT_CUSTOM_DOWNSTREAM_OOB: Custom out-of-band downstream event.
* @GST_EVENT_CUSTOM_BOTH: Custom upstream or downstream event.
* In-band when travelling downstream.
* @GST_EVENT_CUSTOM_BOTH_OOB: Custom upstream or downstream out-of-band event.
*
* #GstEventType lists the standard event types that can be sent in a pipeline.
*
* The custom event types can be used for private messages between elements
* that can't be expressed using normal
* GStreamer buffer passing semantics. Custom events carry an arbitrary
* #GstStructure.
* Specific custom events are distinguished by the name of the structure.
*/
/* NOTE: keep in sync with quark registration in gstevent.c */
typedef enum {
GST_EVENT_UNKNOWN = GST_EVENT_MAKE_TYPE (0, 0, 0),
/* bidirectional events */
GST_EVENT_FLUSH_START = GST_EVENT_MAKE_TYPE (1, 0, FLAG(BOTH)),
GST_EVENT_FLUSH_STOP = GST_EVENT_MAKE_TYPE (2, 0, FLAG(BOTH) | FLAG(SERIALIZED)),
/* downstream serialized events */
GST_EVENT_CAPS = GST_EVENT_MAKE_TYPE (5, 1, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
GST_EVENT_SEGMENT = GST_EVENT_MAKE_TYPE (6, 2, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
GST_EVENT_TAG = GST_EVENT_MAKE_TYPE (7, 3, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
GST_EVENT_BUFFERSIZE = GST_EVENT_MAKE_TYPE (8, 4, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
GST_EVENT_SINK_MESSAGE = GST_EVENT_MAKE_TYPE (9, 5, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
GST_EVENT_EOS = GST_EVENT_MAKE_TYPE (10, 6, FLAG(DOWNSTREAM) | FLAG(SERIALIZED) | FLAG(STICKY)),
/* upstream events */
GST_EVENT_QOS = GST_EVENT_MAKE_TYPE (15, 0, FLAG(UPSTREAM)),
GST_EVENT_SEEK = GST_EVENT_MAKE_TYPE (16, 0, FLAG(UPSTREAM)),
GST_EVENT_NAVIGATION = GST_EVENT_MAKE_TYPE (17, 0, FLAG(UPSTREAM)),
GST_EVENT_LATENCY = GST_EVENT_MAKE_TYPE (18, 0, FLAG(UPSTREAM)),
GST_EVENT_STEP = GST_EVENT_MAKE_TYPE (19, 0, FLAG(UPSTREAM)),
GST_EVENT_RECONFIGURE = GST_EVENT_MAKE_TYPE (20, 0, FLAG(UPSTREAM)),
/* custom events start here */
GST_EVENT_CUSTOM_UPSTREAM = GST_EVENT_MAKE_TYPE (32, 0, FLAG(UPSTREAM)),
GST_EVENT_CUSTOM_DOWNSTREAM = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)),
GST_EVENT_CUSTOM_DOWNSTREAM_OOB = GST_EVENT_MAKE_TYPE (32, 0, FLAG(DOWNSTREAM)),
GST_EVENT_CUSTOM_BOTH = GST_EVENT_MAKE_TYPE (32, 0, FLAG(BOTH) | FLAG(SERIALIZED)),
GST_EVENT_CUSTOM_BOTH_OOB = GST_EVENT_MAKE_TYPE (32, 0, FLAG(BOTH))
} GstEventType;
#undef FLAG
#include <gst/gstminiobject.h>
#include <gst/gstformat.h>
#include <gst/gstobject.h>
#include <gst/gstclock.h>
#include <gst/gststructure.h>
#include <gst/gsttaglist.h>
#include <gst/gstsegment.h>
#include <gst/gstsegment.h>
#include <gst/gstmessage.h>
G_BEGIN_DECLS
extern GType _gst_event_type;
#define GST_TYPE_EVENT (_gst_event_type)
#define GST_IS_EVENT(obj) (GST_IS_MINI_OBJECT_TYPE (obj, GST_TYPE_EVENT))
#define GST_EVENT_CAST(obj) ((GstEvent *)(obj))
#define GST_EVENT(obj) (GST_EVENT_CAST(obj))
/**
* GST_EVENT_TRACE_NAME:
*
* The name used for memory allocation tracing
*/
#define GST_EVENT_TRACE_NAME "GstEvent"
/**
* GST_EVENT_TYPE:
* @event: the event to query
*
* Get the #GstEventType of the event.
*/
#define GST_EVENT_TYPE(event) (GST_EVENT_CAST(event)->type)
/**
* GST_EVENT_TYPE_NAME:
* @event: the event to query
*
* Get a constant string representation of the #GstEventType of the event.
*/
#define GST_EVENT_TYPE_NAME(event) (gst_event_type_get_name(GST_EVENT_TYPE(event)))
/**
* GST_EVENT_TIMESTAMP:
* @event: the event to query
*
* Get the #GstClockTime timestamp of the event. This is the time when the event
* was created.
*/
#define GST_EVENT_TIMESTAMP(event) (GST_EVENT_CAST(event)->timestamp)
/**
* GST_EVENT_SEQNUM:
* @event: the event to query
*
* The sequence number of @event.
*/
#define GST_EVENT_SEQNUM(event) (GST_EVENT_CAST(event)->seqnum)
/**
* GST_EVENT_IS_UPSTREAM:
* @ev: the event to query
*
* Check if an event can travel upstream.
*/
#define GST_EVENT_IS_UPSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_UPSTREAM)
/**
* GST_EVENT_IS_DOWNSTREAM:
* @ev: the event to query
*
* Check if an event can travel downstream.
*/
#define GST_EVENT_IS_DOWNSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_DOWNSTREAM)
/**
* GST_EVENT_IS_SERIALIZED:
* @ev: the event to query
*
* Check if an event is serialized with the data stream.
*/
#define GST_EVENT_IS_SERIALIZED(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_SERIALIZED)
/**
* GST_EVENT_IS_STICKY:
* @ev: the event to query
*
* Check if an event is sticky on the pads.
*/
#define GST_EVENT_IS_STICKY(ev) !!(GST_EVENT_TYPE (ev) & GST_EVENT_TYPE_STICKY)
/**
* gst_event_is_writable:
* @ev: a #GstEvent
*
* Tests if you can safely write data into a event's structure or validly
* modify the seqnum and timestamp field.
*/
#define gst_event_is_writable(ev) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (ev))
/**
* gst_event_make_writable:
* @ev: (transfer full): a #GstEvent
*
* Makes a writable event from the given event. If the source event is
* already writable, this will simply return the same event. A copy will
* otherwise be made using gst_event_copy().
*
* Returns: (transfer full): a writable event which may or may not be the
* same as @ev
*/
#define gst_event_make_writable(ev) GST_EVENT_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (ev)))
/**
* gst_event_replace:
* @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
* to be replaced.
* @new_event: (allow-none) (transfer none): pointer to a #GstEvent that will
* replace the event pointed to by @old_event.
*
* Modifies a pointer to a #GstEvent to point to a different #GstEvent. The
* modification is done atomically (so this is useful for ensuring thread safety
* in some cases), and the reference counts are updated appropriately (the old
* event is unreffed, the new one is reffed).
*
* Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
*
* Returns: TRUE if @new_event was different from @old_event
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC void gst_event_replace (GstEvent **old_event, GstEvent *new_event);
#endif
static inline void
gst_event_replace (GstEvent **old_event, GstEvent *new_event)
{
gst_mini_object_replace ((GstMiniObject **) old_event, (GstMiniObject *) new_event);
}
/**
* gst_event_steal:
* @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
* to be stolen.
*
* Atomically replace the #GstEvent pointed to by @old_event with NULL and
* return the original event.
*
* Returns: the #GstEvent that was in @old_event
*/
#define gst_event_steal(old_event) \
GST_EVENT_CAST (gst_mini_object_steal ((GstMiniObject **)(old_event)))
/**
* gst_event_take:
* @old_event: (inout) (transfer full): pointer to a pointer to a #GstEvent
* to be stolen.
* @new_event: (allow-none) (transfer full): pointer to a #GstEvent that will
* replace the event pointed to by @old_event.
*
* Modifies a pointer to a #GstEvent to point to a different #GstEvent. This
* function is similar to gst_event_replace() except that it takes ownership of
* @new_event.
*
* Either @new_event or the #GstEvent pointed to by @old_event may be NULL.
*
* Returns: TRUE if @new_event was different from @old_event
*/
#define gst_event_take(old_event,new_event) \
gst_mini_object_take ((GstMiniObject **)(old_event), GST_MINI_OBJECT_CAST (new_event))
/**
* GstQOSType:
* @GST_QOS_TYPE_OVERFLOW: The QoS event type that is produced when downstream
* elements are producing data too quickly and the element can't keep up
* processing the data. Upstream should reduce their processing rate. This
* type is also used when buffers arrive early or in time.
* @GST_QOS_TYPE_UNDERFLOW: The QoS event type that is produced when downstream
* elements are producing data too slowly and need to speed up their processing
* rate.
* @GST_QOS_TYPE_THROTTLE: The QoS event type that is produced when the
* application enabled throttling to limit the datarate.
*
* The different types of QoS events that can be given to the
* gst_event_new_qos() method.
*
* Since: 0.10.33
*/
typedef enum {
GST_QOS_TYPE_OVERFLOW = 0,
GST_QOS_TYPE_UNDERFLOW = 1,
GST_QOS_TYPE_THROTTLE = 2
} GstQOSType;
/**
* GstEvent:
* @mini_object: the parent structure
* @type: the #GstEventType of the event
* @timestamp: the timestamp of the event
* @seqnum: the sequence number of the event
*
* A #GstEvent.
*/
struct _GstEvent {
GstMiniObject mini_object;
/*< public >*/ /* with COW */
GstEventType type;
guint64 timestamp;
guint32 seqnum;
};
const gchar* gst_event_type_get_name (GstEventType type);
GQuark gst_event_type_to_quark (GstEventType type);
GstEventTypeFlags
gst_event_type_get_flags (GstEventType type);
/* refcounting */
/**
* gst_event_ref:
* @event: The event to refcount
*
* Increase the refcount of this event.
*
* Returns: (transfer full): @event (for convenience when doing assignments)
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC GstEvent * gst_event_ref (GstEvent * event);
#endif
static inline GstEvent *
gst_event_ref (GstEvent * event)
{
return (GstEvent *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (event));
}
/**
* gst_event_unref:
* @event: (transfer full): the event to refcount
*
* Decrease the refcount of an event, freeing it if the refcount reaches 0.
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC void gst_event_unref (GstEvent * event);
#endif
static inline void
gst_event_unref (GstEvent * event)
{
gst_mini_object_unref (GST_MINI_OBJECT_CAST (event));
}
/* copy event */
/**
* gst_event_copy:
* @event: The event to copy
*
* Copy the event using the event specific copy function.
*
* Returns: (transfer full): the new event
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC GstEvent * gst_event_copy (const GstEvent * event);
#endif
static inline GstEvent *
gst_event_copy (const GstEvent * event)
{
return GST_EVENT_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (event)));
}
GType gst_event_get_type (void);
/* custom event */
GstEvent* gst_event_new_custom (GstEventType type, GstStructure *structure);
const GstStructure *
gst_event_get_structure (GstEvent *event);
GstStructure * gst_event_writable_structure (GstEvent *event);
gboolean gst_event_has_name (GstEvent *event, const gchar *name);
/* identifiers for events and messages */
guint32 gst_event_get_seqnum (GstEvent *event);
void gst_event_set_seqnum (GstEvent *event, guint32 seqnum);
/* flush events */
GstEvent * gst_event_new_flush_start (void);
GstEvent * gst_event_new_flush_stop (gboolean reset_time);
void gst_event_parse_flush_stop (GstEvent *event, gboolean *reset_time);
/* EOS event */
GstEvent * gst_event_new_eos (void);
/* Caps events */
GstEvent * gst_event_new_caps (GstCaps *caps);
void gst_event_parse_caps (GstEvent *event, GstCaps **caps);
/* segment event */
GstEvent* gst_event_new_segment (const GstSegment *segment);
void gst_event_parse_segment (GstEvent *event, const GstSegment **segment);
void gst_event_copy_segment (GstEvent *event, GstSegment *segment);
/* tag event */
GstEvent* gst_event_new_tag (GstTagList *taglist);
void gst_event_parse_tag (GstEvent *event, GstTagList **taglist);
/* buffer */
GstEvent * gst_event_new_buffer_size (GstFormat format, gint64 minsize, gint64 maxsize,
gboolean async);
void gst_event_parse_buffer_size (GstEvent *event, GstFormat *format, gint64 *minsize,
gint64 *maxsize, gboolean *async);
/* sink message */
GstEvent* gst_event_new_sink_message (GstMessage *msg);
void gst_event_parse_sink_message (GstEvent *event, GstMessage **msg);
/* QOS events */
GstEvent* gst_event_new_qos (GstQOSType type, gdouble proportion,
GstClockTimeDiff diff, GstClockTime timestamp);
void gst_event_parse_qos (GstEvent *event, GstQOSType *type,
gdouble *proportion, GstClockTimeDiff *diff,
GstClockTime *timestamp);
/* seek event */
GstEvent* gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
GstSeekType start_type, gint64 start,
GstSeekType stop_type, gint64 stop);
void gst_event_parse_seek (GstEvent *event, gdouble *rate, GstFormat *format,
GstSeekFlags *flags,
GstSeekType *start_type, gint64 *start,
GstSeekType *stop_type, gint64 *stop);
/* navigation event */
GstEvent* gst_event_new_navigation (GstStructure *structure);
/* latency event */
GstEvent* gst_event_new_latency (GstClockTime latency);
void gst_event_parse_latency (GstEvent *event, GstClockTime *latency);
/* step event */
GstEvent* gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
gboolean flush, gboolean intermediate);
void gst_event_parse_step (GstEvent *event, GstFormat *format, guint64 *amount,
gdouble *rate, gboolean *flush, gboolean *intermediate);
/* renegotiate event */
GstEvent* gst_event_new_reconfigure (void);
G_END_DECLS
#endif /* __GST_EVENT_H__ */