gstreamer/libs/gst/base/gstbasesrc.h
Mark Nauwelaerts f8168cd75f basesrc: add dynamic size handling
This allows subclass to indicate that size reported by src may not be static
and should as such be updated regularly, rather than only when really
needed.

Particular examples are filesrc or fdsrc reading from a file that is still
growing (e.g. being downloaded).

Fixes #652037.
2011-06-08 20:16:25 +02:00

263 lines
10 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
* 2005 Wim Taymans <wim@fluendo.com>
*
* gstbasesrc.h:
*
* 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_BASE_SRC_H__
#define __GST_BASE_SRC_H__
#include <gst/gst.h>
G_BEGIN_DECLS
#define GST_TYPE_BASE_SRC (gst_base_src_get_type())
#define GST_BASE_SRC(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BASE_SRC,GstBaseSrc))
#define GST_BASE_SRC_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_BASE_SRC,GstBaseSrcClass))
#define GST_BASE_SRC_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_BASE_SRC, GstBaseSrcClass))
#define GST_IS_BASE_SRC(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BASE_SRC))
#define GST_IS_BASE_SRC_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_BASE_SRC))
#define GST_BASE_SRC_CAST(obj) ((GstBaseSrc *)(obj))
/**
* GstBaseSrcFlags:
* @GST_BASE_SRC_STARTED: has source been started
* @GST_BASE_SRC_FLAG_LAST: offset to define more flags
*
* The #GstElement flags that a basesrc element may have.
*/
typedef enum {
GST_BASE_SRC_STARTED = (GST_ELEMENT_FLAG_LAST << 0),
/* padding */
GST_BASE_SRC_FLAG_LAST = (GST_ELEMENT_FLAG_LAST << 2)
} GstBaseSrcFlags;
typedef struct _GstBaseSrc GstBaseSrc;
typedef struct _GstBaseSrcClass GstBaseSrcClass;
typedef struct _GstBaseSrcPrivate GstBaseSrcPrivate;
/**
* GST_BASE_SRC_PAD:
* @obj: base source instance
*
* Gives the pointer to the #GstPad object of the element.
*/
#define GST_BASE_SRC_PAD(obj) (GST_BASE_SRC_CAST (obj)->srcpad)
/**
* GstBaseSrc:
*
* The opaque #GstBaseSrc data structure.
*/
struct _GstBaseSrc {
GstElement element;
/*< protected >*/
GstPad *srcpad;
/* available to subclass implementations */
/* MT-protected (with LIVE_LOCK) */
GMutex *live_lock;
GCond *live_cond;
gboolean is_live;
gboolean live_running;
/* MT-protected (with LOCK) */
gint blocksize; /* size of buffers when operating push based */
gboolean can_activate_push; /* some scheduling properties */
GstActivateMode pad_mode;
gboolean seekable; /* not used anymore */
gboolean random_access;
GstClockID clock_id; /* for syncing */
GstClockTime end_time;
/* MT-protected (with STREAM_LOCK *and* OBJECT_LOCK) */
GstSegment segment;
/* MT-protected (with STREAM_LOCK) */
gboolean need_newsegment;
guint64 offset; /* current offset in the resource, unused */
guint64 size; /* total size of the resource, unused */
gint num_buffers;
gint num_buffers_left;
/*< private >*/
union {
struct {
/* FIXME: those fields should be moved into the private struct */
gboolean typefind;
gboolean running;
GstEvent *pending_seek;
} ABI;
gpointer _gst_reserved[GST_PADDING_LARGE-1];
} data;
GstBaseSrcPrivate *priv;
};
/**
* GstBaseSrcClass:
* @parent_class: Element parent class
* @get_caps: Called to get the caps to report
* @set_caps: Notify subclass of changed output caps
* @negotiate: Negotiated the caps with the peer.
* @newsegment: Generate and send a new_segment event (UNUSED)
* @start: Start processing. Subclasses should open resources and prepare
* to produce data.
* @stop: Stop processing. Subclasses should use this to close resources.
* @get_times: Given a buffer, return the start and stop time when it
* should be pushed out. The base class will sync on the clock using
* these times.
* @get_size: Return the total size of the resource, in the configured format.
* @is_seekable: Check if the source can seek
* @unlock: Unlock any pending access to the resource. Subclasses should
* unblock any blocked function ASAP. In particular, any create() function in
* progress should be unblocked and should return GST_FLOW_WRONG_STATE. Any
* future @create<!-- -->() function call should also return GST_FLOW_WRONG_STATE
* until the @unlock_stop<!-- -->() function has been called.
* @unlock_stop: Clear the previous unlock request. Subclasses should clear
* any state they set during unlock(), such as clearing command queues.
* @event: Override this to implement custom event handling.
* @create: Ask the subclass to create a buffer with offset and size.
* When the subclass returns GST_FLOW_OK, it MUST return a buffer of the
* requested size unless fewer bytes are available because an EOS condition
* is near. No buffer should be returned when the return value is different
* from GST_FLOW_OK. A return value of GST_FLOW_UNEXPECTED signifies that the
* end of stream is reached.
* @do_seek: Perform seeking on the resource to the indicated segment.
* @prepare_seek_segment: Prepare the GstSegment that will be passed to the
* do_seek vmethod for executing a seek request. Sub-classes should override
* this if they support seeking in formats other than the configured native
* format. By default, it tries to convert the seek arguments to the
* configured native format and prepare a segment in that format.
* Since: 0.10.13
* @query: Handle a requested query.
* @check_get_range: Check whether the source would support pull-based
* operation if it were to be opened now. This vfunc is optional, but
* should be implemented if possible to avoid unnecessary start/stop
* cycles. The default implementation will open and close the resource
* to find out whether get_range is supported, and that is usually
* undesirable.
* @fixate: Called during negotiation if caps need fixating. Implement instead of
* setting a fixate function on the source pad.
*
* Subclasses can override any of the available virtual methods or not, as
* needed. At the minimum, the @create method should be overridden to produce
* buffers.
*/
struct _GstBaseSrcClass {
GstElementClass parent_class;
/*< public >*/
/* virtual methods for subclasses */
/* get caps from subclass */
GstCaps* (*get_caps) (GstBaseSrc *src);
/* notify the subclass of new caps */
gboolean (*set_caps) (GstBaseSrc *src, GstCaps *caps);
/* decide on caps */
gboolean (*negotiate) (GstBaseSrc *src);
/* generate and send a newsegment (UNUSED) */
gboolean (*newsegment) (GstBaseSrc *src);
/* start and stop processing, ideal for opening/closing the resource */
gboolean (*start) (GstBaseSrc *src);
gboolean (*stop) (GstBaseSrc *src);
/* given a buffer, return start and stop time when it should be pushed
* out. The base class will sync on the clock using these times. */
void (*get_times) (GstBaseSrc *src, GstBuffer *buffer,
GstClockTime *start, GstClockTime *end);
/* get the total size of the resource in bytes */
gboolean (*get_size) (GstBaseSrc *src, guint64 *size);
/* check if the resource is seekable */
gboolean (*is_seekable) (GstBaseSrc *src);
/* unlock any pending access to the resource. subclasses should unlock
* any function ASAP. */
gboolean (*unlock) (GstBaseSrc *src);
/* notify subclasses of an event */
gboolean (*event) (GstBaseSrc *src, GstEvent *event);
/* ask the subclass to create a buffer with offset and size */
GstFlowReturn (*create) (GstBaseSrc *src, guint64 offset, guint size,
GstBuffer **buf);
/* additions that change padding... */
/* notify subclasses of a seek */
gboolean (*do_seek) (GstBaseSrc *src, GstSegment *segment);
/* notify subclasses of a query */
gboolean (*query) (GstBaseSrc *src, GstQuery *query);
/* check whether the source would support pull-based operation if
* it were to be opened now. This vfunc is optional, but should be
* implemented if possible to avoid unnecessary start/stop cycles.
* The default implementation will open and close the resource to
* find out whether get_range is supported and that is usually
* undesirable. */
gboolean (*check_get_range) (GstBaseSrc *src);
/* called if, in negotiation, caps need fixating */
void (*fixate) (GstBaseSrc *src, GstCaps *caps);
/* Clear any pending unlock request, as we succeeded in unlocking */
gboolean (*unlock_stop) (GstBaseSrc *src);
/* Prepare the segment on which to perform do_seek(), converting to the
* current basesrc format. */
gboolean (*prepare_seek_segment) (GstBaseSrc *src, GstEvent *seek,
GstSegment *segment);
/*< private >*/
gpointer _gst_reserved[GST_PADDING_LARGE - 6];
};
GType gst_base_src_get_type (void);
GstFlowReturn gst_base_src_wait_playing (GstBaseSrc *src);
void gst_base_src_set_live (GstBaseSrc *src, gboolean live);
gboolean gst_base_src_is_live (GstBaseSrc *src);
void gst_base_src_set_format (GstBaseSrc *src, GstFormat format);
void gst_base_src_set_dynamic_size (GstBaseSrc * src, gboolean dynamic);
gboolean gst_base_src_query_latency (GstBaseSrc *src, gboolean * live,
GstClockTime * min_latency,
GstClockTime * max_latency);
void gst_base_src_set_blocksize (GstBaseSrc *src, gulong blocksize);
gulong gst_base_src_get_blocksize (GstBaseSrc *src);
void gst_base_src_set_do_timestamp (GstBaseSrc *src, gboolean timestamp);
gboolean gst_base_src_get_do_timestamp (GstBaseSrc *src);
gboolean gst_base_src_new_seamless_segment (GstBaseSrc *src, gint64 start, gint64 stop, gint64 position);
G_END_DECLS
#endif /* __GST_BASE_SRC_H__ */