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gstreamer/libs/gst/base/gstbasesrc.c

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/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000,2005 Wim Taymans <wim@fluendo.com>
*
* gstbasesrc.c:
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gstbasesrc
* @short_description: Base class for getrange based source elements
* @see_also: #GstPushSrc, #GstBaseTransform, #GstBaseSink
*
* This is a generic base class for source elements. The following
* types of sources are supported:
* <itemizedlist>
* <listitem><para>random access sources like files</para></listitem>
* <listitem><para>seekable sources</para></listitem>
* <listitem><para>live sources</para></listitem>
* </itemizedlist>
*
* The source can be configured to operate in any #GstFormat with the
* gst_base_src_set_format() method. The currently set format determines
* the format of the internal #GstSegment and any #GST_EVENT_SEGMENT
* events. The default format for #GstBaseSrc is #GST_FORMAT_BYTES.
*
* #GstBaseSrc always supports push mode scheduling. If the following
* conditions are met, it also supports pull mode scheduling:
* <itemizedlist>
* <listitem><para>The format is set to #GST_FORMAT_BYTES (default).</para>
* </listitem>
* <listitem><para>#GstBaseSrcClass.is_seekable() returns %TRUE.</para>
* </listitem>
* </itemizedlist>
*
* If all the conditions are met for operating in pull mode, #GstBaseSrc is
* automatically seekable in push mode as well. The following conditions must
* be met to make the element seekable in push mode when the format is not
* #GST_FORMAT_BYTES:
* <itemizedlist>
* <listitem><para>
* #GstBaseSrcClass.is_seekable() returns %TRUE.
* </para></listitem>
* <listitem><para>
* #GstBaseSrcClass.query() can convert all supported seek formats to the
* internal format as set with gst_base_src_set_format().
* </para></listitem>
* <listitem><para>
* #GstBaseSrcClass.do_seek() is implemented, performs the seek and returns
* %TRUE.
* </para></listitem>
* </itemizedlist>
*
* When the element does not meet the requirements to operate in pull mode, the
* offset and length in the #GstBaseSrcClass.create() method should be ignored.
* It is recommended to subclass #GstPushSrc instead, in this situation. If the
* element can operate in pull mode but only with specific offsets and
* lengths, it is allowed to generate an error when the wrong values are passed
* to the #GstBaseSrcClass.create() function.
*
* #GstBaseSrc has support for live sources. Live sources are sources that when
* paused discard data, such as audio or video capture devices. A typical live
* source also produces data at a fixed rate and thus provides a clock to publish
* this rate.
* Use gst_base_src_set_live() to activate the live source mode.
*
* A live source does not produce data in the PAUSED state. This means that the
* #GstBaseSrcClass.create() method will not be called in PAUSED but only in
* PLAYING. To signal the pipeline that the element will not produce data, the
* return value from the READY to PAUSED state will be
* #GST_STATE_CHANGE_NO_PREROLL.
*
* A typical live source will timestamp the buffers it creates with the
* current running time of the pipeline. This is one reason why a live source
* can only produce data in the PLAYING state, when the clock is actually
* distributed and running.
*
* Live sources that synchronize and block on the clock (an audio source, for
* example) can use gst_base_src_wait_playing() when the
* #GstBaseSrcClass.create() function was interrupted by a state change to
* PAUSED.
*
* The #GstBaseSrcClass.get_times() method can be used to implement pseudo-live
* sources. It only makes sense to implement the #GstBaseSrcClass.get_times()
* function if the source is a live source. The #GstBaseSrcClass.get_times()
* function should return timestamps starting from 0, as if it were a non-live
* source. The base class will make sure that the timestamps are transformed
* into the current running_time. The base source will then wait for the
* calculated running_time before pushing out the buffer.
*
* For live sources, the base class will by default report a latency of 0.
* For pseudo live sources, the base class will by default measure the difference
* between the first buffer timestamp and the start time of get_times and will
* report this value as the latency.
* Subclasses should override the query function when this behaviour is not
* acceptable.
*
* There is only support in #GstBaseSrc for exactly one source pad, which
* should be named "src". A source implementation (subclass of #GstBaseSrc)
* should install a pad template in its class_init function, like so:
* |[
* static void
* my_element_class_init (GstMyElementClass *klass)
* {
* GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
* // srctemplate should be a #GstStaticPadTemplate with direction
* // #GST_PAD_SRC and name "src"
* gst_element_class_add_pad_template (gstelement_class,
* gst_static_pad_template_get (&amp;srctemplate));
*
* gst_element_class_set_static_metadata (gstelement_class,
* "Source name",
* "Source",
* "My Source element",
* "The author &lt;my.sink@my.email&gt;");
* }
* ]|
*
* <refsect2>
* <title>Controlled shutdown of live sources in applications</title>
* <para>
* Applications that record from a live source may want to stop recording
* in a controlled way, so that the recording is stopped, but the data
* already in the pipeline is processed to the end (remember that many live
* sources would go on recording forever otherwise). For that to happen the
* application needs to make the source stop recording and send an EOS
* event down the pipeline. The application would then wait for an
* EOS message posted on the pipeline's bus to know when all data has
* been processed and the pipeline can safely be stopped.
*
* An application may send an EOS event to a source element to make it
* perform the EOS logic (send EOS event downstream or post a
* #GST_MESSAGE_SEGMENT_DONE on the bus). This can typically be done
* with the gst_element_send_event() function on the element or its parent bin.
*
* After the EOS has been sent to the element, the application should wait for
* an EOS message to be posted on the pipeline's bus. Once this EOS message is
* received, it may safely shut down the entire pipeline.
*
* Last reviewed on 2007-12-19 (0.10.16)
* </para>
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdlib.h>
#include <string.h>
#include <gst/gst_private.h>
#include <gst/glib-compat-private.h>
#include "gstbasesrc.h"
#include "gsttypefindhelper.h"
#include <gst/gst-i18n-lib.h>
GST_DEBUG_CATEGORY_STATIC (gst_base_src_debug);
#define GST_CAT_DEFAULT gst_base_src_debug
#define GST_LIVE_GET_LOCK(elem) (&GST_BASE_SRC_CAST(elem)->live_lock)
#define GST_LIVE_LOCK(elem) g_mutex_lock(GST_LIVE_GET_LOCK(elem))
#define GST_LIVE_TRYLOCK(elem) g_mutex_trylock(GST_LIVE_GET_LOCK(elem))
#define GST_LIVE_UNLOCK(elem) g_mutex_unlock(GST_LIVE_GET_LOCK(elem))
#define GST_LIVE_GET_COND(elem) (&GST_BASE_SRC_CAST(elem)->live_cond)
#define GST_LIVE_WAIT(elem) g_cond_wait (GST_LIVE_GET_COND (elem), GST_LIVE_GET_LOCK (elem))
#define GST_LIVE_WAIT_UNTIL(elem, end_time) g_cond_timed_wait (GST_LIVE_GET_COND (elem), GST_LIVE_GET_LOCK (elem), end_time)
#define GST_LIVE_SIGNAL(elem) g_cond_signal (GST_LIVE_GET_COND (elem));
#define GST_LIVE_BROADCAST(elem) g_cond_broadcast (GST_LIVE_GET_COND (elem));
#define GST_ASYNC_GET_COND(elem) (&GST_BASE_SRC_CAST(elem)->priv->async_cond)
#define GST_ASYNC_WAIT(elem) g_cond_wait (GST_ASYNC_GET_COND (elem), GST_OBJECT_GET_LOCK (elem))
#define GST_ASYNC_SIGNAL(elem) g_cond_signal (GST_ASYNC_GET_COND (elem));
/* BaseSrc signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_BLOCKSIZE 4096
#define DEFAULT_NUM_BUFFERS -1
#define DEFAULT_TYPEFIND FALSE
#define DEFAULT_DO_TIMESTAMP FALSE
enum
{
PROP_0,
PROP_BLOCKSIZE,
PROP_NUM_BUFFERS,
PROP_TYPEFIND,
PROP_DO_TIMESTAMP
};
#define GST_BASE_SRC_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BASE_SRC, GstBaseSrcPrivate))
struct _GstBaseSrcPrivate
{
gboolean discont;
gboolean flushing;
GstFlowReturn start_result;
gboolean async;
/* if a stream-start event should be sent */
gboolean stream_start_pending;
/* if segment should be sent and a
* seqnum if it was originated by a seek */
gboolean segment_pending;
guint32 segment_seqnum;
/* if EOS is pending (atomic) */
gint pending_eos;
/* startup latency is the time it takes between going to PLAYING and producing
* the first BUFFER with running_time 0. This value is included in the latency
* reporting. */
GstClockTime latency;
/* timestamp offset, this is the offset add to the values of gst_times for
* pseudo live sources */
GstClockTimeDiff ts_offset;
gboolean do_timestamp;
volatile gint dynamic_size;
/* stream sequence number */
guint32 seqnum;
/* pending events (TAG, CUSTOM_BOTH, CUSTOM_DOWNSTREAM) to be
* pushed in the data stream */
GList *pending_events;
volatile gint have_events;
/* QoS *//* with LOCK */
gboolean qos_enabled;
gdouble proportion;
GstClockTime earliest_time;
GstBufferPool *pool;
GstAllocator *allocator;
GstAllocationParams params;
GCond async_cond;
};
static GstElementClass *parent_class = NULL;
static void gst_base_src_class_init (GstBaseSrcClass * klass);
static void gst_base_src_init (GstBaseSrc * src, gpointer g_class);
static void gst_base_src_finalize (GObject * object);
GType
gst_base_src_get_type (void)
{
static volatile gsize base_src_type = 0;
if (g_once_init_enter (&base_src_type)) {
GType _type;
static const GTypeInfo base_src_info = {
sizeof (GstBaseSrcClass),
NULL,
NULL,
(GClassInitFunc) gst_base_src_class_init,
NULL,
NULL,
sizeof (GstBaseSrc),
0,
(GInstanceInitFunc) gst_base_src_init,
};
_type = g_type_register_static (GST_TYPE_ELEMENT,
"GstBaseSrc", &base_src_info, G_TYPE_FLAG_ABSTRACT);
g_once_init_leave (&base_src_type, _type);
}
return base_src_type;
}
static GstCaps *gst_base_src_default_get_caps (GstBaseSrc * bsrc,
GstCaps * filter);
static GstCaps *gst_base_src_default_fixate (GstBaseSrc * src, GstCaps * caps);
static GstCaps *gst_base_src_fixate (GstBaseSrc * src, GstCaps * caps);
static gboolean gst_base_src_is_random_access (GstBaseSrc * src);
static gboolean gst_base_src_activate_mode (GstPad * pad, GstObject * parent,
GstPadMode mode, gboolean active);
static void gst_base_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_base_src_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_base_src_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static gboolean gst_base_src_send_event (GstElement * elem, GstEvent * event);
static gboolean gst_base_src_default_event (GstBaseSrc * src, GstEvent * event);
static gboolean gst_base_src_query (GstPad * pad, GstObject * parent,
GstQuery * query);
static gboolean gst_base_src_activate_pool (GstBaseSrc * basesrc,
gboolean active);
static gboolean gst_base_src_default_negotiate (GstBaseSrc * basesrc);
static gboolean gst_base_src_default_do_seek (GstBaseSrc * src,
GstSegment * segment);
static gboolean gst_base_src_default_query (GstBaseSrc * src, GstQuery * query);
static gboolean gst_base_src_default_prepare_seek_segment (GstBaseSrc * src,
GstEvent * event, GstSegment * segment);
static GstFlowReturn gst_base_src_default_create (GstBaseSrc * basesrc,
guint64 offset, guint size, GstBuffer ** buf);
static GstFlowReturn gst_base_src_default_alloc (GstBaseSrc * basesrc,
guint64 offset, guint size, GstBuffer ** buf);
static gboolean gst_base_src_decide_allocation_default (GstBaseSrc * basesrc,
GstQuery * query);
static gboolean gst_base_src_set_flushing (GstBaseSrc * basesrc,
gboolean flushing, gboolean live_play, gboolean * playing);
static gboolean gst_base_src_start (GstBaseSrc * basesrc);
static gboolean gst_base_src_stop (GstBaseSrc * basesrc);
static GstStateChangeReturn gst_base_src_change_state (GstElement * element,
GstStateChange transition);
static void gst_base_src_loop (GstPad * pad);
static GstFlowReturn gst_base_src_getrange (GstPad * pad, GstObject * parent,
guint64 offset, guint length, GstBuffer ** buf);
static GstFlowReturn gst_base_src_get_range (GstBaseSrc * src, guint64 offset,
guint length, GstBuffer ** buf);
static gboolean gst_base_src_seekable (GstBaseSrc * src);
static gboolean gst_base_src_negotiate (GstBaseSrc * basesrc);
static gboolean gst_base_src_update_length (GstBaseSrc * src, guint64 offset,
guint * length, gboolean force);
static void
gst_base_src_class_init (GstBaseSrcClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = G_OBJECT_CLASS (klass);
gstelement_class = GST_ELEMENT_CLASS (klass);
GST_DEBUG_CATEGORY_INIT (gst_base_src_debug, "basesrc", 0, "basesrc element");
g_type_class_add_private (klass, sizeof (GstBaseSrcPrivate));
parent_class = g_type_class_peek_parent (klass);
gobject_class->finalize = gst_base_src_finalize;
gobject_class->set_property = gst_base_src_set_property;
gobject_class->get_property = gst_base_src_get_property;
g_object_class_install_property (gobject_class, PROP_BLOCKSIZE,
g_param_spec_uint ("blocksize", "Block size",
"Size in bytes to read per buffer (-1 = default)", 0, G_MAXUINT,
DEFAULT_BLOCKSIZE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_NUM_BUFFERS,
g_param_spec_int ("num-buffers", "num-buffers",
"Number of buffers to output before sending EOS (-1 = unlimited)",
-1, G_MAXINT, DEFAULT_NUM_BUFFERS, G_PARAM_READWRITE |
G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_TYPEFIND,
g_param_spec_boolean ("typefind", "Typefind",
"Run typefind before negotiating", DEFAULT_TYPEFIND,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_DO_TIMESTAMP,
g_param_spec_boolean ("do-timestamp", "Do timestamp",
"Apply current stream time to buffers", DEFAULT_DO_TIMESTAMP,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gstelement_class->change_state =
GST_DEBUG_FUNCPTR (gst_base_src_change_state);
gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_base_src_send_event);
klass->get_caps = GST_DEBUG_FUNCPTR (gst_base_src_default_get_caps);
klass->negotiate = GST_DEBUG_FUNCPTR (gst_base_src_default_negotiate);
klass->fixate = GST_DEBUG_FUNCPTR (gst_base_src_default_fixate);
klass->prepare_seek_segment =
GST_DEBUG_FUNCPTR (gst_base_src_default_prepare_seek_segment);
klass->do_seek = GST_DEBUG_FUNCPTR (gst_base_src_default_do_seek);
klass->query = GST_DEBUG_FUNCPTR (gst_base_src_default_query);
klass->event = GST_DEBUG_FUNCPTR (gst_base_src_default_event);
klass->create = GST_DEBUG_FUNCPTR (gst_base_src_default_create);
klass->alloc = GST_DEBUG_FUNCPTR (gst_base_src_default_alloc);
klass->decide_allocation =
GST_DEBUG_FUNCPTR (gst_base_src_decide_allocation_default);
/* Registering debug symbols for function pointers */
GST_DEBUG_REGISTER_FUNCPTR (gst_base_src_activate_mode);
GST_DEBUG_REGISTER_FUNCPTR (gst_base_src_event);
GST_DEBUG_REGISTER_FUNCPTR (gst_base_src_query);
GST_DEBUG_REGISTER_FUNCPTR (gst_base_src_getrange);
GST_DEBUG_REGISTER_FUNCPTR (gst_base_src_fixate);
}
static void
gst_base_src_init (GstBaseSrc * basesrc, gpointer g_class)
{
GstPad *pad;
GstPadTemplate *pad_template;
basesrc->priv = GST_BASE_SRC_GET_PRIVATE (basesrc);
basesrc->is_live = FALSE;
g_mutex_init (&basesrc->live_lock);
g_cond_init (&basesrc->live_cond);
basesrc->num_buffers = DEFAULT_NUM_BUFFERS;
basesrc->num_buffers_left = -1;
basesrc->can_activate_push = TRUE;
pad_template =
gst_element_class_get_pad_template (GST_ELEMENT_CLASS (g_class), "src");
g_return_if_fail (pad_template != NULL);
GST_DEBUG_OBJECT (basesrc, "creating src pad");
pad = gst_pad_new_from_template (pad_template, "src");
GST_DEBUG_OBJECT (basesrc, "setting functions on src pad");
gst_pad_set_activatemode_function (pad, gst_base_src_activate_mode);
gst_pad_set_event_function (pad, gst_base_src_event);
gst_pad_set_query_function (pad, gst_base_src_query);
gst_pad_set_getrange_function (pad, gst_base_src_getrange);
/* hold pointer to pad */
basesrc->srcpad = pad;
GST_DEBUG_OBJECT (basesrc, "adding src pad");
gst_element_add_pad (GST_ELEMENT (basesrc), pad);
basesrc->blocksize = DEFAULT_BLOCKSIZE;
basesrc->clock_id = NULL;
/* we operate in BYTES by default */
gst_base_src_set_format (basesrc, GST_FORMAT_BYTES);
basesrc->typefind = DEFAULT_TYPEFIND;
basesrc->priv->do_timestamp = DEFAULT_DO_TIMESTAMP;
g_atomic_int_set (&basesrc->priv->have_events, FALSE);
g_cond_init (&basesrc->priv->async_cond);
basesrc->priv->start_result = GST_FLOW_FLUSHING;
GST_OBJECT_FLAG_UNSET (basesrc, GST_BASE_SRC_FLAG_STARTED);
GST_OBJECT_FLAG_UNSET (basesrc, GST_BASE_SRC_FLAG_STARTING);
GST_OBJECT_FLAG_SET (basesrc, GST_ELEMENT_FLAG_SOURCE);
GST_DEBUG_OBJECT (basesrc, "init done");
}
static void
gst_base_src_finalize (GObject * object)
{
GstBaseSrc *basesrc;
GstEvent **event_p;
basesrc = GST_BASE_SRC (object);
g_mutex_clear (&basesrc->live_lock);
g_cond_clear (&basesrc->live_cond);
g_cond_clear (&basesrc->priv->async_cond);
event_p = &basesrc->pending_seek;
gst_event_replace (event_p, NULL);
if (basesrc->priv->pending_events) {
g_list_foreach (basesrc->priv->pending_events, (GFunc) gst_event_unref,
NULL);
g_list_free (basesrc->priv->pending_events);
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
/**
* gst_base_src_wait_playing:
* @src: the src
*
* If the #GstBaseSrcClass.create() method performs its own synchronisation
* against the clock it must unblock when going from PLAYING to the PAUSED state
* and call this method before continuing to produce the remaining data.
*
* This function will block until a state change to PLAYING happens (in which
* case this function returns #GST_FLOW_OK) or the processing must be stopped due
* to a state change to READY or a FLUSH event (in which case this function
* returns #GST_FLOW_FLUSHING).
*
* Returns: #GST_FLOW_OK if @src is PLAYING and processing can
* continue. Any other return value should be returned from the create vmethod.
*/
GstFlowReturn
gst_base_src_wait_playing (GstBaseSrc * src)
{
g_return_val_if_fail (GST_IS_BASE_SRC (src), GST_FLOW_ERROR);
do {
/* block until the state changes, or we get a flush, or something */
GST_DEBUG_OBJECT (src, "live source waiting for running state");
GST_LIVE_WAIT (src);
GST_DEBUG_OBJECT (src, "live source unlocked");
if (src->priv->flushing)
goto flushing;
} while (G_UNLIKELY (!src->live_running));
return GST_FLOW_OK;
/* ERRORS */
flushing:
{
GST_DEBUG_OBJECT (src, "we are flushing");
return GST_FLOW_FLUSHING;
}
}
/**
* gst_base_src_set_live:
* @src: base source instance
* @live: new live-mode
*
* If the element listens to a live source, @live should
* be set to %TRUE.
*
* A live source will not produce data in the PAUSED state and
* will therefore not be able to participate in the PREROLL phase
* of a pipeline. To signal this fact to the application and the
* pipeline, the state change return value of the live source will
* be GST_STATE_CHANGE_NO_PREROLL.
*/
void
gst_base_src_set_live (GstBaseSrc * src, gboolean live)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
GST_OBJECT_LOCK (src);
src->is_live = live;
GST_OBJECT_UNLOCK (src);
}
/**
* gst_base_src_is_live:
* @src: base source instance
*
* Check if an element is in live mode.
*
* Returns: %TRUE if element is in live mode.
*/
gboolean
gst_base_src_is_live (GstBaseSrc * src)
{
gboolean result;
g_return_val_if_fail (GST_IS_BASE_SRC (src), FALSE);
GST_OBJECT_LOCK (src);
result = src->is_live;
GST_OBJECT_UNLOCK (src);
return result;
}
/**
* gst_base_src_set_format:
* @src: base source instance
* @format: the format to use
*
* Sets the default format of the source. This will be the format used
* for sending SEGMENT events and for performing seeks.
*
* If a format of GST_FORMAT_BYTES is set, the element will be able to
* operate in pull mode if the #GstBaseSrcClass.is_seekable() returns TRUE.
*
* This function must only be called in states < %GST_STATE_PAUSED.
*/
void
gst_base_src_set_format (GstBaseSrc * src, GstFormat format)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
g_return_if_fail (GST_STATE (src) <= GST_STATE_READY);
GST_OBJECT_LOCK (src);
gst_segment_init (&src->segment, format);
GST_OBJECT_UNLOCK (src);
}
/**
* gst_base_src_set_dynamic_size:
* @src: base source instance
* @dynamic: new dynamic size mode
*
* If not @dynamic, size is only updated when needed, such as when trying to
* read past current tracked size. Otherwise, size is checked for upon each
* read.
*/
void
gst_base_src_set_dynamic_size (GstBaseSrc * src, gboolean dynamic)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
g_atomic_int_set (&src->priv->dynamic_size, dynamic);
}
/**
* gst_base_src_set_async:
* @src: base source instance
* @async: new async mode
*
* Configure async behaviour in @src, no state change will block. The open,
* close, start, stop, play and pause virtual methods will be executed in a
* different thread and are thus allowed to perform blocking operations. Any
* blocking operation should be unblocked with the unlock vmethod.
*/
void
gst_base_src_set_async (GstBaseSrc * src, gboolean async)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
GST_OBJECT_LOCK (src);
src->priv->async = async;
GST_OBJECT_UNLOCK (src);
}
/**
* gst_base_src_is_async:
* @src: base source instance
*
* Get the current async behaviour of @src. See also gst_base_src_set_async().
*
* Returns: %TRUE if @src is operating in async mode.
*/
gboolean
gst_base_src_is_async (GstBaseSrc * src)
{
gboolean res;
g_return_val_if_fail (GST_IS_BASE_SRC (src), FALSE);
GST_OBJECT_LOCK (src);
res = src->priv->async;
GST_OBJECT_UNLOCK (src);
return res;
}
/**
* gst_base_src_query_latency:
* @src: the source
* @live: (out) (allow-none): if the source is live
* @min_latency: (out) (allow-none): the min latency of the source
* @max_latency: (out) (allow-none): the max latency of the source
*
* Query the source for the latency parameters. @live will be TRUE when @src is
* configured as a live source. @min_latency will be set to the difference
* between the running time and the timestamp of the first buffer.
* @max_latency is always the undefined value of -1.
*
* This function is mostly used by subclasses.
*
* Returns: TRUE if the query succeeded.
*/
gboolean
gst_base_src_query_latency (GstBaseSrc * src, gboolean * live,
GstClockTime * min_latency, GstClockTime * max_latency)
{
GstClockTime min;
g_return_val_if_fail (GST_IS_BASE_SRC (src), FALSE);
GST_OBJECT_LOCK (src);
if (live)
*live = src->is_live;
/* if we have a startup latency, report this one, else report 0. Subclasses
* are supposed to override the query function if they want something
* else. */
if (src->priv->latency != -1)
min = src->priv->latency;
else
min = 0;
if (min_latency)
*min_latency = min;
if (max_latency)
*max_latency = -1;
GST_LOG_OBJECT (src, "latency: live %d, min %" GST_TIME_FORMAT
", max %" GST_TIME_FORMAT, src->is_live, GST_TIME_ARGS (min),
GST_TIME_ARGS (-1));
GST_OBJECT_UNLOCK (src);
return TRUE;
}
/**
* gst_base_src_set_blocksize:
* @src: the source
* @blocksize: the new blocksize in bytes
*
* Set the number of bytes that @src will push out with each buffer. When
* @blocksize is set to -1, a default length will be used.
*/
void
gst_base_src_set_blocksize (GstBaseSrc * src, guint blocksize)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
GST_OBJECT_LOCK (src);
src->blocksize = blocksize;
GST_OBJECT_UNLOCK (src);
}
/**
* gst_base_src_get_blocksize:
* @src: the source
*
* Get the number of bytes that @src will push out with each buffer.
*
* Returns: the number of bytes pushed with each buffer.
*/
guint
gst_base_src_get_blocksize (GstBaseSrc * src)
{
gint res;
g_return_val_if_fail (GST_IS_BASE_SRC (src), 0);
GST_OBJECT_LOCK (src);
res = src->blocksize;
GST_OBJECT_UNLOCK (src);
return res;
}
/**
* gst_base_src_set_do_timestamp:
* @src: the source
* @timestamp: enable or disable timestamping
*
* Configure @src to automatically timestamp outgoing buffers based on the
* current running_time of the pipeline. This property is mostly useful for live
* sources.
*/
void
gst_base_src_set_do_timestamp (GstBaseSrc * src, gboolean timestamp)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
GST_OBJECT_LOCK (src);
src->priv->do_timestamp = timestamp;
if (timestamp && src->segment.format != GST_FORMAT_TIME)
gst_segment_init (&src->segment, GST_FORMAT_TIME);
GST_OBJECT_UNLOCK (src);
}
/**
* gst_base_src_get_do_timestamp:
* @src: the source
*
* Query if @src timestamps outgoing buffers based on the current running_time.
*
* Returns: %TRUE if the base class will automatically timestamp outgoing buffers.
*/
gboolean
gst_base_src_get_do_timestamp (GstBaseSrc * src)
{
gboolean res;
g_return_val_if_fail (GST_IS_BASE_SRC (src), FALSE);
GST_OBJECT_LOCK (src);
res = src->priv->do_timestamp;
GST_OBJECT_UNLOCK (src);
return res;
}
/**
* gst_base_src_new_seamless_segment:
* @src: The source
* @start: The new start value for the segment
* @stop: Stop value for the new segment
* @time: The new time value for the start of the new segment
*
* Prepare a new seamless segment for emission downstream. This function must
* only be called by derived sub-classes, and only from the create() function,
* as the stream-lock needs to be held.
*
* The format for the new segment will be the current format of the source, as
* configured with gst_base_src_set_format()
*
* Returns: %TRUE if preparation of the seamless segment succeeded.
*/
gboolean
gst_base_src_new_seamless_segment (GstBaseSrc * src, gint64 start, gint64 stop,
gint64 time)
{
gboolean res = TRUE;
GST_OBJECT_LOCK (src);
src->segment.base = gst_segment_to_running_time (&src->segment,
src->segment.format, src->segment.position);
src->segment.position = src->segment.start = start;
src->segment.stop = stop;
src->segment.time = time;
/* Mark pending segment. Will be sent before next data */
src->priv->segment_pending = TRUE;
src->priv->segment_seqnum = gst_util_seqnum_next ();
GST_DEBUG_OBJECT (src,
"Starting new seamless segment. Start %" GST_TIME_FORMAT " stop %"
GST_TIME_FORMAT " time %" GST_TIME_FORMAT " base %" GST_TIME_FORMAT,
GST_TIME_ARGS (start), GST_TIME_ARGS (stop), GST_TIME_ARGS (time),
GST_TIME_ARGS (src->segment.base));
GST_OBJECT_UNLOCK (src);
src->priv->discont = TRUE;
src->running = TRUE;
return res;
}
static gboolean
gst_base_src_send_stream_start (GstBaseSrc * src)
{
gboolean ret = TRUE;
if (src->priv->stream_start_pending) {
gchar *stream_id;
GstEvent *event;
stream_id =
gst_pad_create_stream_id (src->srcpad, GST_ELEMENT_CAST (src), NULL);
GST_DEBUG_OBJECT (src, "Pushing STREAM_START");
event = gst_event_new_stream_start (stream_id);
gst_event_set_group_id (event, gst_util_group_id_next ());
ret = gst_pad_push_event (src->srcpad, event);
src->priv->stream_start_pending = FALSE;
g_free (stream_id);
}
return ret;
}
/**
* gst_base_src_set_caps:
* @src: a #GstBaseSrc
* @caps: a #GstCaps
*
* Set new caps on the basesrc source pad.
*
* Returns: %TRUE if the caps could be set
*/
gboolean
gst_base_src_set_caps (GstBaseSrc * src, GstCaps * caps)
{
GstBaseSrcClass *bclass;
gboolean res = TRUE;
bclass = GST_BASE_SRC_GET_CLASS (src);
gst_base_src_send_stream_start (src);
if (bclass->set_caps)
res = bclass->set_caps (src, caps);
if (res)
res = gst_pad_push_event (src->srcpad, gst_event_new_caps (caps));
return res;
}
static GstCaps *
gst_base_src_default_get_caps (GstBaseSrc * bsrc, GstCaps * filter)
{
GstCaps *caps = NULL;
GstPadTemplate *pad_template;
GstBaseSrcClass *bclass;
bclass = GST_BASE_SRC_GET_CLASS (bsrc);
pad_template =
gst_element_class_get_pad_template (GST_ELEMENT_CLASS (bclass), "src");
if (pad_template != NULL) {
caps = gst_pad_template_get_caps (pad_template);
if (filter) {
GstCaps *intersection;
intersection =
gst_caps_intersect_full (filter, caps, GST_CAPS_INTERSECT_FIRST);
gst_caps_unref (caps);
caps = intersection;
}
}
return caps;
}
static GstCaps *
gst_base_src_default_fixate (GstBaseSrc * bsrc, GstCaps * caps)
{
GST_DEBUG_OBJECT (bsrc, "using default caps fixate function");
return gst_caps_fixate (caps);
}
static GstCaps *
gst_base_src_fixate (GstBaseSrc * bsrc, GstCaps * caps)
{
GstBaseSrcClass *bclass;
bclass = GST_BASE_SRC_GET_CLASS (bsrc);
if (bclass->fixate)
caps = bclass->fixate (bsrc, caps);
return caps;
}
static gboolean
gst_base_src_default_query (GstBaseSrc * src, GstQuery * query)
{
gboolean res;
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_POSITION:
{
GstFormat format;
gst_query_parse_position (query, &format, NULL);
GST_DEBUG_OBJECT (src, "position query in format %s",
gst_format_get_name (format));
switch (format) {
case GST_FORMAT_PERCENT:
{
gint64 percent;
gint64 position;
gint64 duration;
GST_OBJECT_LOCK (src);
position = src->segment.position;
duration = src->segment.duration;
GST_OBJECT_UNLOCK (src);
if (position != -1 && duration != -1) {
if (position < duration)
percent = gst_util_uint64_scale (GST_FORMAT_PERCENT_MAX, position,
duration);
else
percent = GST_FORMAT_PERCENT_MAX;
} else
percent = -1;
gst_query_set_position (query, GST_FORMAT_PERCENT, percent);
res = TRUE;
break;
}
default:
{
gint64 position;
GstFormat seg_format;
GST_OBJECT_LOCK (src);
position =
gst_segment_to_stream_time (&src->segment, src->segment.format,
src->segment.position);
seg_format = src->segment.format;
GST_OBJECT_UNLOCK (src);
if (position != -1) {
/* convert to requested format */
res =
gst_pad_query_convert (src->srcpad, seg_format,
position, format, &position);
} else
res = TRUE;
gst_query_set_position (query, format, position);
break;
}
}
break;
}
case GST_QUERY_DURATION:
{
GstFormat format;
gst_query_parse_duration (query, &format, NULL);
GST_DEBUG_OBJECT (src, "duration query in format %s",
gst_format_get_name (format));
switch (format) {
case GST_FORMAT_PERCENT:
gst_query_set_duration (query, GST_FORMAT_PERCENT,
GST_FORMAT_PERCENT_MAX);
res = TRUE;
break;
default:
{
gint64 duration;
GstFormat seg_format;
guint length = 0;
/* may have to refresh duration */
gst_base_src_update_length (src, 0, &length,
g_atomic_int_get (&src->priv->dynamic_size));
/* this is the duration as configured by the subclass. */
GST_OBJECT_LOCK (src);
duration = src->segment.duration;
seg_format = src->segment.format;
GST_OBJECT_UNLOCK (src);
GST_LOG_OBJECT (src, "duration %" G_GINT64_FORMAT ", format %s",
duration, gst_format_get_name (seg_format));
if (duration != -1) {
/* convert to requested format, if this fails, we have a duration
* but we cannot answer the query, we must return FALSE. */
res =
gst_pad_query_convert (src->srcpad, seg_format,
duration, format, &duration);
} else {
/* The subclass did not configure a duration, we assume that the
* media has an unknown duration then and we return TRUE to report
* this. Note that this is not the same as returning FALSE, which
* means that we cannot report the duration at all. */
res = TRUE;
}
gst_query_set_duration (query, format, duration);
break;
}
}
break;
}
case GST_QUERY_SEEKING:
{
GstFormat format, seg_format;
gint64 duration;
GST_OBJECT_LOCK (src);
duration = src->segment.duration;
seg_format = src->segment.format;
GST_OBJECT_UNLOCK (src);
gst_query_parse_seeking (query, &format, NULL, NULL, NULL);
if (format == seg_format) {
gst_query_set_seeking (query, seg_format,
gst_base_src_seekable (src), 0, duration);
res = TRUE;
} else {
/* FIXME 0.11: return TRUE + seekable=FALSE for SEEKING query here */
/* Don't reply to the query to make up for demuxers which don't
* handle the SEEKING query yet. Players like Totem will fall back
* to the duration when the SEEKING query isn't answered. */
res = FALSE;
}
break;
}
case GST_QUERY_SEGMENT:
{
GstFormat format;
gint64 start, stop;
GST_OBJECT_LOCK (src);
format = src->segment.format;
start =
gst_segment_to_stream_time (&src->segment, format,
src->segment.start);
if ((stop = src->segment.stop) == -1)
stop = src->segment.duration;
else
stop = gst_segment_to_stream_time (&src->segment, format, stop);
gst_query_set_segment (query, src->segment.rate, format, start, stop);
GST_OBJECT_UNLOCK (src);
res = TRUE;
break;
}
case GST_QUERY_FORMATS:
{
gst_query_set_formats (query, 3, GST_FORMAT_DEFAULT,
GST_FORMAT_BYTES, GST_FORMAT_PERCENT);
res = TRUE;
break;
}
case GST_QUERY_CONVERT:
{
GstFormat src_fmt, dest_fmt;
gint64 src_val, dest_val;
gst_query_parse_convert (query, &src_fmt, &src_val, &dest_fmt, &dest_val);
/* we can only convert between equal formats... */
if (src_fmt == dest_fmt) {
dest_val = src_val;
res = TRUE;
} else
res = FALSE;
gst_query_set_convert (query, src_fmt, src_val, dest_fmt, dest_val);
break;
}
case GST_QUERY_LATENCY:
{
GstClockTime min, max;
gboolean live;
/* Subclasses should override and implement something useful */
res = gst_base_src_query_latency (src, &live, &min, &max);
GST_LOG_OBJECT (src, "report latency: live %d, min %" GST_TIME_FORMAT
", max %" GST_TIME_FORMAT, live, GST_TIME_ARGS (min),
GST_TIME_ARGS (max));
gst_query_set_latency (query, live, min, max);
break;
}
case GST_QUERY_JITTER:
case GST_QUERY_RATE:
res = FALSE;
break;
case GST_QUERY_BUFFERING:
{
GstFormat format, seg_format;
gint64 start, stop, estimated;
gst_query_parse_buffering_range (query, &format, NULL, NULL, NULL);
GST_DEBUG_OBJECT (src, "buffering query in format %s",
gst_format_get_name (format));
GST_OBJECT_LOCK (src);
if (src->random_access) {
estimated = 0;
start = 0;
if (format == GST_FORMAT_PERCENT)
stop = GST_FORMAT_PERCENT_MAX;
else
stop = src->segment.duration;
} else {
estimated = -1;
start = -1;
stop = -1;
}
seg_format = src->segment.format;
GST_OBJECT_UNLOCK (src);
/* convert to required format. When the conversion fails, we can't answer
* the query. When the value is unknown, we can don't perform conversion
* but report TRUE. */
if (format != GST_FORMAT_PERCENT && stop != -1) {
res = gst_pad_query_convert (src->srcpad, seg_format,
stop, format, &stop);
} else {
res = TRUE;
}
if (res && format != GST_FORMAT_PERCENT && start != -1)
res = gst_pad_query_convert (src->srcpad, seg_format,
start, format, &start);
gst_query_set_buffering_range (query, format, start, stop, estimated);
break;
}
case GST_QUERY_SCHEDULING:
{
gboolean random_access;
random_access = gst_base_src_is_random_access (src);
/* we can operate in getrange mode if the native format is bytes
* and we are seekable, this condition is set in the random_access
* flag and is set in the _start() method. */
gst_query_set_scheduling (query, GST_SCHEDULING_FLAG_SEEKABLE, 1, -1, 0);
if (random_access)
gst_query_add_scheduling_mode (query, GST_PAD_MODE_PULL);
gst_query_add_scheduling_mode (query, GST_PAD_MODE_PUSH);
res = TRUE;
break;
}
case GST_QUERY_CAPS:
{
GstBaseSrcClass *bclass;
GstCaps *caps, *filter;
bclass = GST_BASE_SRC_GET_CLASS (src);
if (bclass->get_caps) {
gst_query_parse_caps (query, &filter);
if ((caps = bclass->get_caps (src, filter))) {
gst_query_set_caps_result (query, caps);
gst_caps_unref (caps);
res = TRUE;
} else {
res = FALSE;
}
} else
res = FALSE;
break;
}
case GST_QUERY_URI:{
if (GST_IS_URI_HANDLER (src)) {
gchar *uri = gst_uri_handler_get_uri (GST_URI_HANDLER (src));
if (uri != NULL) {
gst_query_set_uri (query, uri);
g_free (uri);
res = TRUE;
} else {
res = FALSE;
}
} else {
res = FALSE;
}
break;
}
default:
res = FALSE;
break;
}
GST_DEBUG_OBJECT (src, "query %s returns %d", GST_QUERY_TYPE_NAME (query),
res);
return res;
}
static gboolean
gst_base_src_query (GstPad * pad, GstObject * parent, GstQuery * query)
{
GstBaseSrc *src;
GstBaseSrcClass *bclass;
gboolean result = FALSE;
src = GST_BASE_SRC (parent);
bclass = GST_BASE_SRC_GET_CLASS (src);
if (bclass->query)
result = bclass->query (src, query);
return result;
}
static gboolean
gst_base_src_default_do_seek (GstBaseSrc * src, GstSegment * segment)
{
gboolean res = TRUE;
/* update our offset if the start/stop position was updated */
if (segment->format == GST_FORMAT_BYTES) {
segment->time = segment->start;
} else if (segment->start == 0) {
/* seek to start, we can implement a default for this. */
segment->time = 0;
} else {
res = FALSE;
GST_INFO_OBJECT (src, "Can't do a default seek");
}
return res;
}
static gboolean
gst_base_src_do_seek (GstBaseSrc * src, GstSegment * segment)
{
GstBaseSrcClass *bclass;
gboolean result = FALSE;
bclass = GST_BASE_SRC_GET_CLASS (src);
GST_INFO_OBJECT (src, "seeking: %" GST_SEGMENT_FORMAT, segment);
if (bclass->do_seek)
result = bclass->do_seek (src, segment);
return result;
}
#define SEEK_TYPE_IS_RELATIVE(t) (((t) != GST_SEEK_TYPE_NONE) && ((t) != GST_SEEK_TYPE_SET))
static gboolean
gst_base_src_default_prepare_seek_segment (GstBaseSrc * src, GstEvent * event,
GstSegment * segment)
{
/* By default, we try one of 2 things:
* - For absolute seek positions, convert the requested position to our
* configured processing format and place it in the output segment \
* - For relative seek positions, convert our current (input) values to the
* seek format, adjust by the relative seek offset and then convert back to
* the processing format
*/
GstSeekType start_type, stop_type;
gint64 start, stop;
GstSeekFlags flags;
GstFormat seek_format, dest_format;
gdouble rate;
gboolean update;
gboolean res = TRUE;
gst_event_parse_seek (event, &rate, &seek_format, &flags,
&start_type, &start, &stop_type, &stop);
dest_format = segment->format;
if (seek_format == dest_format) {
gst_segment_do_seek (segment, rate, seek_format, flags,
start_type, start, stop_type, stop, &update);
return TRUE;
}
if (start_type != GST_SEEK_TYPE_NONE) {
/* FIXME: Handle seek_end by converting the input segment vals */
res =
gst_pad_query_convert (src->srcpad, seek_format, start, dest_format,
&start);
start_type = GST_SEEK_TYPE_SET;
}
if (res && stop_type != GST_SEEK_TYPE_NONE) {
/* FIXME: Handle seek_end by converting the input segment vals */
res =
gst_pad_query_convert (src->srcpad, seek_format, stop, dest_format,
&stop);
stop_type = GST_SEEK_TYPE_SET;
}
/* And finally, configure our output segment in the desired format */
gst_segment_do_seek (segment, rate, dest_format, flags, start_type, start,
stop_type, stop, &update);
if (!res)
goto no_format;
return res;
no_format:
{
GST_DEBUG_OBJECT (src, "undefined format given, seek aborted.");
return FALSE;
}
}
static gboolean
gst_base_src_prepare_seek_segment (GstBaseSrc * src, GstEvent * event,
GstSegment * seeksegment)
{
GstBaseSrcClass *bclass;
gboolean result = FALSE;
bclass = GST_BASE_SRC_GET_CLASS (src);
if (bclass->prepare_seek_segment)
result = bclass->prepare_seek_segment (src, event, seeksegment);
return result;
}
static GstFlowReturn
gst_base_src_default_alloc (GstBaseSrc * src, guint64 offset,
guint size, GstBuffer ** buffer)
{
GstFlowReturn ret;
GstBaseSrcPrivate *priv = src->priv;
if (priv->pool) {
ret = gst_buffer_pool_acquire_buffer (priv->pool, buffer, NULL);
} else if (size != -1) {
*buffer = gst_buffer_new_allocate (priv->allocator, size, &priv->params);
if (G_UNLIKELY (*buffer == NULL))
goto alloc_failed;
ret = GST_FLOW_OK;
} else {
GST_WARNING_OBJECT (src, "Not trying to alloc %u bytes. Blocksize not set?",
size);
goto alloc_failed;
}
return ret;
/* ERRORS */
alloc_failed:
{
GST_ERROR_OBJECT (src, "Failed to allocate %u bytes", size);
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
gst_base_src_default_create (GstBaseSrc * src, guint64 offset,
guint size, GstBuffer ** buffer)
{
GstBaseSrcClass *bclass;
GstFlowReturn ret;
GstBuffer *res_buf;
bclass = GST_BASE_SRC_GET_CLASS (src);
if (G_UNLIKELY (!bclass->alloc))
goto no_function;
if (G_UNLIKELY (!bclass->fill))
goto no_function;
if (*buffer == NULL) {
/* downstream did not provide us with a buffer to fill, allocate one
* ourselves */
ret = bclass->alloc (src, offset, size, &res_buf);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto alloc_failed;
} else {
res_buf = *buffer;
}
if (G_LIKELY (size > 0)) {
/* only call fill when there is a size */
ret = bclass->fill (src, offset, size, res_buf);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto not_ok;
}
*buffer = res_buf;
return GST_FLOW_OK;
/* ERRORS */
no_function:
{
GST_DEBUG_OBJECT (src, "no fill or alloc function");
return GST_FLOW_NOT_SUPPORTED;
}
alloc_failed:
{
GST_DEBUG_OBJECT (src, "Failed to allocate buffer of %u bytes", size);
return ret;
}
not_ok:
{
GST_DEBUG_OBJECT (src, "fill returned %d (%s)", ret,
gst_flow_get_name (ret));
if (*buffer == NULL)
gst_buffer_unref (res_buf);
return ret;
}
}
/* this code implements the seeking. It is a good example
* handling all cases.
*
* A seek updates the currently configured segment.start
* and segment.stop values based on the SEEK_TYPE. If the
* segment.start value is updated, a seek to this new position
* should be performed.
*
* The seek can only be executed when we are not currently
* streaming any data, to make sure that this is the case, we
* acquire the STREAM_LOCK which is taken when we are in the
* _loop() function or when a getrange() is called. Normally
* we will not receive a seek if we are operating in pull mode
* though. When we operate as a live source we might block on the live
* cond, which does not release the STREAM_LOCK. Therefore we will try
* to grab the LIVE_LOCK instead of the STREAM_LOCK to make sure it is
* safe to perform the seek.
*
* When we are in the loop() function, we might be in the middle
* of pushing a buffer, which might block in a sink. To make sure
* that the push gets unblocked we push out a FLUSH_START event.
* Our loop function will get a FLUSHING return value from
* the push and will pause, effectively releasing the STREAM_LOCK.
*
* For a non-flushing seek, we pause the task, which might eventually
* release the STREAM_LOCK. We say eventually because when the sink
* blocks on the sample we might wait a very long time until the sink
* unblocks the sample. In any case we acquire the STREAM_LOCK and
* can continue the seek. A non-flushing seek is normally done in a
* running pipeline to perform seamless playback, this means that the sink is
* PLAYING and will return from its chain function.
* In the case of a non-flushing seek we need to make sure that the
* data we output after the seek is continuous with the previous data,
* this is because a non-flushing seek does not reset the running-time
* to 0. We do this by closing the currently running segment, ie. sending
* a new_segment event with the stop position set to the last processed
* position.
*
* After updating the segment.start/stop values, we prepare for
* streaming again. We push out a FLUSH_STOP to make the peer pad
* accept data again and we start our task again.
*
* A segment seek posts a message on the bus saying that the playback
* of the segment started. We store the segment flag internally because
* when we reach the segment.stop we have to post a segment.done
* instead of EOS when doing a segment seek.
*/
static gboolean
gst_base_src_perform_seek (GstBaseSrc * src, GstEvent * event, gboolean unlock)
{
gboolean res = TRUE, tres;
gdouble rate;
GstFormat seek_format, dest_format;
GstSeekFlags flags;
GstSeekType start_type, stop_type;
gint64 start, stop;
gboolean flush, playing;
gboolean update;
gboolean relative_seek = FALSE;
gboolean seekseg_configured = FALSE;
GstSegment seeksegment;
guint32 seqnum;
GstEvent *tevent;
GST_DEBUG_OBJECT (src, "doing seek: %" GST_PTR_FORMAT, event);
GST_OBJECT_LOCK (src);
dest_format = src->segment.format;
GST_OBJECT_UNLOCK (src);
if (event) {
gst_event_parse_seek (event, &rate, &seek_format, &flags,
&start_type, &start, &stop_type, &stop);
relative_seek = SEEK_TYPE_IS_RELATIVE (start_type) ||
SEEK_TYPE_IS_RELATIVE (stop_type);
if (dest_format != seek_format && !relative_seek) {
/* If we have an ABSOLUTE position (SEEK_SET only), we can convert it
* here before taking the stream lock, otherwise we must convert it later,
* once we have the stream lock and can read the last configures segment
* start and stop positions */
gst_segment_init (&seeksegment, dest_format);
if (!gst_base_src_prepare_seek_segment (src, event, &seeksegment))
goto prepare_failed;
seekseg_configured = TRUE;
}
flush = flags & GST_SEEK_FLAG_FLUSH;
seqnum = gst_event_get_seqnum (event);
} else {
flush = FALSE;
/* get next seqnum */
seqnum = gst_util_seqnum_next ();
}
/* send flush start */
if (flush) {
tevent = gst_event_new_flush_start ();
gst_event_set_seqnum (tevent, seqnum);
gst_pad_push_event (src->srcpad, tevent);
} else
gst_pad_pause_task (src->srcpad);
/* unblock streaming thread. */
if (unlock)
gst_base_src_set_flushing (src, TRUE, FALSE, &playing);
/* grab streaming lock, this should eventually be possible, either
* because the task is paused, our streaming thread stopped
* or because our peer is flushing. */
GST_PAD_STREAM_LOCK (src->srcpad);
if (G_UNLIKELY (src->priv->seqnum == seqnum)) {
/* we have seen this event before, issue a warning for now */
GST_WARNING_OBJECT (src, "duplicate event found %" G_GUINT32_FORMAT,
seqnum);
} else {
src->priv->seqnum = seqnum;
GST_DEBUG_OBJECT (src, "seek with seqnum %" G_GUINT32_FORMAT, seqnum);
}
if (unlock)
gst_base_src_set_flushing (src, FALSE, playing, NULL);
/* If we configured the seeksegment above, don't overwrite it now. Otherwise
* copy the current segment info into the temp segment that we can actually
* attempt the seek with. We only update the real segment if the seek succeeds. */
if (!seekseg_configured) {
memcpy (&seeksegment, &src->segment, sizeof (GstSegment));
/* now configure the final seek segment */
if (event) {
if (seeksegment.format != seek_format) {
/* OK, here's where we give the subclass a chance to convert the relative
* seek into an absolute one in the processing format. We set up any
* absolute seek above, before taking the stream lock. */
if (!gst_base_src_prepare_seek_segment (src, event, &seeksegment)) {
GST_DEBUG_OBJECT (src, "Preparing the seek failed after flushing. "
"Aborting seek");
res = FALSE;
}
} else {
/* The seek format matches our processing format, no need to ask the
* the subclass to configure the segment. */
gst_segment_do_seek (&seeksegment, rate, seek_format, flags,
start_type, start, stop_type, stop, &update);
}
}
/* Else, no seek event passed, so we're just (re)starting the
current segment. */
}
if (res) {
GST_DEBUG_OBJECT (src, "segment configured from %" G_GINT64_FORMAT
" to %" G_GINT64_FORMAT ", position %" G_GINT64_FORMAT,
seeksegment.start, seeksegment.stop, seeksegment.position);
/* do the seek, segment.position contains the new position. */
res = gst_base_src_do_seek (src, &seeksegment);
}
/* and prepare to continue streaming */
if (flush) {
tevent = gst_event_new_flush_stop (TRUE);
gst_event_set_seqnum (tevent, seqnum);
/* send flush stop, peer will accept data and events again. We
* are not yet providing data as we still have the STREAM_LOCK. */
gst_pad_push_event (src->srcpad, tevent);
}
/* The subclass must have converted the segment to the processing format
* by now */
if (res && seeksegment.format != dest_format) {
GST_DEBUG_OBJECT (src, "Subclass failed to prepare a seek segment "
"in the correct format. Aborting seek.");
res = FALSE;
}
/* if the seek was successful, we update our real segment and push
* out the new segment. */
if (res) {
GST_OBJECT_LOCK (src);
memcpy (&src->segment, &seeksegment, sizeof (GstSegment));
GST_OBJECT_UNLOCK (src);
if (seeksegment.flags & GST_SEGMENT_FLAG_SEGMENT) {
GstMessage *message;
message = gst_message_new_segment_start (GST_OBJECT (src),
seeksegment.format, seeksegment.position);
gst_message_set_seqnum (message, seqnum);
gst_element_post_message (GST_ELEMENT (src), message);
}
/* for deriving a stop position for the playback segment from the seek
* segment, we must take the duration when the stop is not set */
/* FIXME: This is never used below */
if ((stop = seeksegment.stop) == -1)
stop = seeksegment.duration;
src->priv->segment_pending = TRUE;
src->priv->segment_seqnum = seqnum;
}
src->priv->discont = TRUE;
src->running = TRUE;
/* and restart the task in case it got paused explicitly or by
* the FLUSH_START event we pushed out. */
tres = gst_pad_start_task (src->srcpad, (GstTaskFunction) gst_base_src_loop,
src->srcpad, NULL);
if (res && !tres)
res = FALSE;
/* and release the lock again so we can continue streaming */
GST_PAD_STREAM_UNLOCK (src->srcpad);
return res;
/* ERROR */
prepare_failed:
GST_DEBUG_OBJECT (src, "Preparing the seek failed before flushing. "
"Aborting seek");
return FALSE;
}
/* all events send to this element directly. This is mainly done from the
* application.
*/
static gboolean
gst_base_src_send_event (GstElement * element, GstEvent * event)
{
GstBaseSrc *src;
gboolean result = FALSE;
GstBaseSrcClass *bclass;
src = GST_BASE_SRC (element);
bclass = GST_BASE_SRC_GET_CLASS (src);
GST_DEBUG_OBJECT (src, "handling event %p %" GST_PTR_FORMAT, event, event);
switch (GST_EVENT_TYPE (event)) {
/* bidirectional events */
case GST_EVENT_FLUSH_START:
GST_DEBUG_OBJECT (src, "pushing flush-start event downstream");
result = gst_pad_push_event (src->srcpad, event);
/* also unblock the create function */
gst_base_src_activate_pool (src, FALSE);
/* unlock any subclasses, we need to do this before grabbing the
* LIVE_LOCK since we hold this lock before going into ::create. We pass an
* unlock to the params because of backwards compat (see seek handler)*/
if (bclass->unlock)
bclass->unlock (src);
/* the live lock is released when we are blocked, waiting for playing or
* when we sync to the clock. */
GST_LIVE_LOCK (src);
src->priv->flushing = TRUE;
/* clear pending EOS if any */
g_atomic_int_set (&src->priv->pending_eos, FALSE);
if (bclass->unlock_stop)
bclass->unlock_stop (src);
if (src->clock_id)
gst_clock_id_unschedule (src->clock_id);
GST_DEBUG_OBJECT (src, "signal");
GST_LIVE_SIGNAL (src);
GST_LIVE_UNLOCK (src);
event = NULL;
break;
case GST_EVENT_FLUSH_STOP:
{
gboolean start;
GST_LIVE_LOCK (src);
src->priv->segment_pending = TRUE;
src->priv->flushing = FALSE;
GST_DEBUG_OBJECT (src, "pushing flush-stop event downstream");
result = gst_pad_push_event (src->srcpad, event);
gst_base_src_activate_pool (src, TRUE);
GST_OBJECT_LOCK (src->srcpad);
start = (GST_PAD_MODE (src->srcpad) == GST_PAD_MODE_PUSH);
GST_OBJECT_UNLOCK (src->srcpad);
if (start)
gst_pad_start_task (src->srcpad, (GstTaskFunction) gst_base_src_loop,
src->srcpad, NULL);
GST_LIVE_UNLOCK (src);
event = NULL;
break;
}
/* downstream serialized events */
case GST_EVENT_EOS:
{
/* queue EOS and make sure the task or pull function performs the EOS
* actions.
*
* We have two possibilities:
*
* - Before we are to enter the _create function, we check the pending_eos
* first and do EOS instead of entering it.
* - If we are in the _create function or we did not manage to set the
* flag fast enough and we are about to enter the _create function,
* we unlock it so that we exit with FLUSHING immediately. We then
* check the EOS flag and do the EOS logic.
*/
g_atomic_int_set (&src->priv->pending_eos, TRUE);
GST_DEBUG_OBJECT (src, "EOS marked, calling unlock");
/* unlock the _create function so that we can check the pending_eos flag
* and we can do EOS. This will eventually release the LIVE_LOCK again so
* that we can grab it and stop the unlock again. We don't take the stream
* lock so that this operation is guaranteed to never block. */
gst_base_src_activate_pool (src, FALSE);
if (bclass->unlock)
bclass->unlock (src);
GST_DEBUG_OBJECT (src, "unlock called, waiting for LIVE_LOCK");
GST_LIVE_LOCK (src);
GST_DEBUG_OBJECT (src, "LIVE_LOCK acquired, calling unlock_stop");
/* now stop the unlock of the streaming thread again. Grabbing the live
* lock is enough because that protects the create function. */
if (bclass->unlock_stop)
bclass->unlock_stop (src);
gst_base_src_activate_pool (src, TRUE);
GST_LIVE_UNLOCK (src);
result = TRUE;
break;
}
case GST_EVENT_SEGMENT:
/* sending random SEGMENT downstream can break sync. */
break;
case GST_EVENT_TAG:
case GST_EVENT_CUSTOM_DOWNSTREAM:
case GST_EVENT_CUSTOM_BOTH:
/* Insert TAG, CUSTOM_DOWNSTREAM, CUSTOM_BOTH in the dataflow */
GST_OBJECT_LOCK (src);
src->priv->pending_events =
g_list_append (src->priv->pending_events, event);
g_atomic_int_set (&src->priv->have_events, TRUE);
GST_OBJECT_UNLOCK (src);
event = NULL;
result = TRUE;
break;
case GST_EVENT_BUFFERSIZE:
/* does not seem to make much sense currently */
break;
/* upstream events */
case GST_EVENT_QOS:
/* elements should override send_event and do something */
break;
case GST_EVENT_SEEK:
{
gboolean started;
GST_OBJECT_LOCK (src->srcpad);
if (GST_PAD_MODE (src->srcpad) == GST_PAD_MODE_PULL)
goto wrong_mode;
started = GST_PAD_MODE (src->srcpad) == GST_PAD_MODE_PUSH;
GST_OBJECT_UNLOCK (src->srcpad);
if (started) {
GST_DEBUG_OBJECT (src, "performing seek");
/* when we are running in push mode, we can execute the
* seek right now. */
result = gst_base_src_perform_seek (src, event, TRUE);
} else {
GstEvent **event_p;
/* else we store the event and execute the seek when we
* get activated */
GST_OBJECT_LOCK (src);
GST_DEBUG_OBJECT (src, "queueing seek");
event_p = &src->pending_seek;
gst_event_replace ((GstEvent **) event_p, event);
GST_OBJECT_UNLOCK (src);
/* assume the seek will work */
result = TRUE;
}
break;
}
case GST_EVENT_NAVIGATION:
/* could make sense for elements that do something with navigation events
* but then they would need to override the send_event function */
break;
case GST_EVENT_LATENCY:
/* does not seem to make sense currently */
break;
/* custom events */
case GST_EVENT_CUSTOM_UPSTREAM:
/* override send_event if you want this */
break;
case GST_EVENT_CUSTOM_DOWNSTREAM_OOB:
case GST_EVENT_CUSTOM_BOTH_OOB:
/* insert a random custom event into the pipeline */
GST_DEBUG_OBJECT (src, "pushing custom OOB event downstream");
result = gst_pad_push_event (src->srcpad, event);
/* we gave away the ref to the event in the push */
event = NULL;
break;
default:
break;
}
done:
/* if we still have a ref to the event, unref it now */
if (event)
gst_event_unref (event);
return result;
/* ERRORS */
wrong_mode:
{
GST_DEBUG_OBJECT (src, "cannot perform seek when operating in pull mode");
GST_OBJECT_UNLOCK (src->srcpad);
result = FALSE;
goto done;
}
}
static gboolean
gst_base_src_seekable (GstBaseSrc * src)
{
GstBaseSrcClass *bclass;
bclass = GST_BASE_SRC_GET_CLASS (src);
if (bclass->is_seekable)
return bclass->is_seekable (src);
else
return FALSE;
}
static void
gst_base_src_update_qos (GstBaseSrc * src,
gdouble proportion, GstClockTimeDiff diff, GstClockTime timestamp)
{
GST_CAT_DEBUG_OBJECT (GST_CAT_QOS, src,
"qos: proportion: %lf, diff %" G_GINT64_FORMAT ", timestamp %"
GST_TIME_FORMAT, proportion, diff, GST_TIME_ARGS (timestamp));
GST_OBJECT_LOCK (src);
src->priv->proportion = proportion;
src->priv->earliest_time = timestamp + diff;
GST_OBJECT_UNLOCK (src);
}
static gboolean
gst_base_src_default_event (GstBaseSrc * src, GstEvent * event)
{
gboolean result;
GST_DEBUG_OBJECT (src, "handle event %" GST_PTR_FORMAT, event);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_SEEK:
/* is normally called when in push mode */
if (!gst_base_src_seekable (src))
goto not_seekable;
result = gst_base_src_perform_seek (src, event, TRUE);
break;
case GST_EVENT_FLUSH_START:
/* cancel any blocking getrange, is normally called
* when in pull mode. */
result = gst_base_src_set_flushing (src, TRUE, FALSE, NULL);
break;
case GST_EVENT_FLUSH_STOP:
result = gst_base_src_set_flushing (src, FALSE, TRUE, NULL);
break;
case GST_EVENT_QOS:
{
gdouble proportion;
GstClockTimeDiff diff;
GstClockTime timestamp;
gst_event_parse_qos (event, NULL, &proportion, &diff, &timestamp);
gst_base_src_update_qos (src, proportion, diff, timestamp);
result = TRUE;
break;
}
case GST_EVENT_RECONFIGURE:
result = TRUE;
break;
case GST_EVENT_LATENCY:
result = TRUE;
break;
default:
result = FALSE;
break;
}
return result;
/* ERRORS */
not_seekable:
{
GST_DEBUG_OBJECT (src, "is not seekable");
return FALSE;
}
}
static gboolean
gst_base_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstBaseSrc *src;
GstBaseSrcClass *bclass;
gboolean result = FALSE;
src = GST_BASE_SRC (parent);
bclass = GST_BASE_SRC_GET_CLASS (src);
if (bclass->event) {
if (!(result = bclass->event (src, event)))
goto subclass_failed;
}
done:
gst_event_unref (event);
return result;
/* ERRORS */
subclass_failed:
{
GST_DEBUG_OBJECT (src, "subclass refused event");
goto done;
}
}
static void
gst_base_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstBaseSrc *src;
src = GST_BASE_SRC (object);
switch (prop_id) {
case PROP_BLOCKSIZE:
gst_base_src_set_blocksize (src, g_value_get_uint (value));
break;
case PROP_NUM_BUFFERS:
src->num_buffers = g_value_get_int (value);
break;
case PROP_TYPEFIND:
src->typefind = g_value_get_boolean (value);
break;
case PROP_DO_TIMESTAMP:
gst_base_src_set_do_timestamp (src, g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_base_src_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstBaseSrc *src;
src = GST_BASE_SRC (object);
switch (prop_id) {
case PROP_BLOCKSIZE:
g_value_set_uint (value, gst_base_src_get_blocksize (src));
break;
case PROP_NUM_BUFFERS:
g_value_set_int (value, src->num_buffers);
break;
case PROP_TYPEFIND:
g_value_set_boolean (value, src->typefind);
break;
case PROP_DO_TIMESTAMP:
g_value_set_boolean (value, gst_base_src_get_do_timestamp (src));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* with STREAM_LOCK and LOCK */
static GstClockReturn
gst_base_src_wait (GstBaseSrc * basesrc, GstClock * clock, GstClockTime time)
{
GstClockReturn ret;
GstClockID id;
id = gst_clock_new_single_shot_id (clock, time);
basesrc->clock_id = id;
/* release the live lock while waiting */
GST_LIVE_UNLOCK (basesrc);
ret = gst_clock_id_wait (id, NULL);
GST_LIVE_LOCK (basesrc);
gst_clock_id_unref (id);
basesrc->clock_id = NULL;
return ret;
}
/* perform synchronisation on a buffer.
* with STREAM_LOCK.
*/
static GstClockReturn
gst_base_src_do_sync (GstBaseSrc * basesrc, GstBuffer * buffer)
{
GstClockReturn result;
GstClockTime start, end;
GstBaseSrcClass *bclass;
GstClockTime base_time;
GstClock *clock;
GstClockTime now = GST_CLOCK_TIME_NONE, pts, dts, timestamp;
gboolean do_timestamp, first, pseudo_live, is_live;
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
start = end = -1;
if (bclass->get_times)
bclass->get_times (basesrc, buffer, &start, &end);
/* get buffer timestamp */
dts = GST_BUFFER_DTS (buffer);
pts = GST_BUFFER_PTS (buffer);
if (GST_CLOCK_TIME_IS_VALID (dts))
timestamp = dts;
else
timestamp = pts;
/* grab the lock to prepare for clocking and calculate the startup
* latency. */
GST_OBJECT_LOCK (basesrc);
is_live = basesrc->is_live;
/* if we are asked to sync against the clock we are a pseudo live element */
pseudo_live = (start != -1 && is_live);
/* check for the first buffer */
first = (basesrc->priv->latency == -1);
if (timestamp != -1 && pseudo_live) {
GstClockTime latency;
/* we have a timestamp and a sync time, latency is the diff */
if (timestamp <= start)
latency = start - timestamp;
else
latency = 0;
if (first) {
GST_DEBUG_OBJECT (basesrc, "pseudo_live with latency %" GST_TIME_FORMAT,
GST_TIME_ARGS (latency));
/* first time we calculate latency, just configure */
basesrc->priv->latency = latency;
} else {
if (basesrc->priv->latency != latency) {
/* we have a new latency, FIXME post latency message */
basesrc->priv->latency = latency;
GST_DEBUG_OBJECT (basesrc, "latency changed to %" GST_TIME_FORMAT,
GST_TIME_ARGS (latency));
}
}
} else if (first) {
GST_DEBUG_OBJECT (basesrc, "no latency needed, live %d, sync %d",
is_live, start != -1);
basesrc->priv->latency = 0;
}
/* get clock, if no clock, we can't sync or do timestamps */
if ((clock = GST_ELEMENT_CLOCK (basesrc)) == NULL)
goto no_clock;
else
gst_object_ref (clock);
base_time = GST_ELEMENT_CAST (basesrc)->base_time;
do_timestamp = basesrc->priv->do_timestamp;
GST_OBJECT_UNLOCK (basesrc);
/* first buffer, calculate the timestamp offset */
if (first) {
GstClockTime running_time;
now = gst_clock_get_time (clock);
running_time = now - base_time;
GST_LOG_OBJECT (basesrc,
"startup PTS: %" GST_TIME_FORMAT ", DTS %" GST_TIME_FORMAT
", running_time %" GST_TIME_FORMAT, GST_TIME_ARGS (pts),
GST_TIME_ARGS (dts), GST_TIME_ARGS (running_time));
if (pseudo_live && timestamp != -1) {
/* live source and we need to sync, add startup latency to all timestamps
* to get the real running_time. Live sources should always timestamp
* according to the current running time. */
basesrc->priv->ts_offset = GST_CLOCK_DIFF (timestamp, running_time);
GST_LOG_OBJECT (basesrc, "live with sync, ts_offset %" GST_TIME_FORMAT,
GST_TIME_ARGS (basesrc->priv->ts_offset));
} else {
basesrc->priv->ts_offset = 0;
GST_LOG_OBJECT (basesrc, "no timestamp offset needed");
}
if (!GST_CLOCK_TIME_IS_VALID (dts)) {
if (do_timestamp) {
dts = running_time;
} else {
if (GST_CLOCK_TIME_IS_VALID (basesrc->segment.start)) {
dts = basesrc->segment.start;
} else {
dts = 0;
}
}
GST_BUFFER_DTS (buffer) = dts;
GST_LOG_OBJECT (basesrc, "created DTS %" GST_TIME_FORMAT,
GST_TIME_ARGS (dts));
}
} else {
/* not the first buffer, the timestamp is the diff between the clock and
* base_time */
if (do_timestamp && !GST_CLOCK_TIME_IS_VALID (dts)) {
now = gst_clock_get_time (clock);
dts = now - base_time;
GST_BUFFER_DTS (buffer) = dts;
GST_LOG_OBJECT (basesrc, "created DTS %" GST_TIME_FORMAT,
GST_TIME_ARGS (dts));
}
}
if (!GST_CLOCK_TIME_IS_VALID (pts)) {
if (!GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT))
pts = dts;
GST_BUFFER_PTS (buffer) = dts;
GST_LOG_OBJECT (basesrc, "created PTS %" GST_TIME_FORMAT,
GST_TIME_ARGS (pts));
}
/* if we don't have a buffer timestamp, we don't sync */
if (!GST_CLOCK_TIME_IS_VALID (start))
goto no_sync;
if (is_live) {
/* for pseudo live sources, add our ts_offset to the timestamp */
if (GST_CLOCK_TIME_IS_VALID (pts))
GST_BUFFER_PTS (buffer) += basesrc->priv->ts_offset;
if (GST_CLOCK_TIME_IS_VALID (dts))
GST_BUFFER_DTS (buffer) += basesrc->priv->ts_offset;
start += basesrc->priv->ts_offset;
}
GST_LOG_OBJECT (basesrc,
"waiting for clock, base time %" GST_TIME_FORMAT
", stream_start %" GST_TIME_FORMAT,
GST_TIME_ARGS (base_time), GST_TIME_ARGS (start));
result = gst_base_src_wait (basesrc, clock, start + base_time);
gst_object_unref (clock);
GST_LOG_OBJECT (basesrc, "clock entry done: %d", result);
return result;
/* special cases */
no_clock:
{
GST_DEBUG_OBJECT (basesrc, "we have no clock");
GST_OBJECT_UNLOCK (basesrc);
return GST_CLOCK_OK;
}
no_sync:
{
GST_DEBUG_OBJECT (basesrc, "no sync needed");
gst_object_unref (clock);
return GST_CLOCK_OK;
}
}
/* Called with STREAM_LOCK and LIVE_LOCK */
static gboolean
gst_base_src_update_length (GstBaseSrc * src, guint64 offset, guint * length,
gboolean force)
{
guint64 size, maxsize;
GstBaseSrcClass *bclass;
GstFormat format;
gint64 stop;
bclass = GST_BASE_SRC_GET_CLASS (src);
format = src->segment.format;
stop = src->segment.stop;
/* get total file size */
size = src->segment.duration;
/* only operate if we are working with bytes */
if (format != GST_FORMAT_BYTES)
return TRUE;
/* the max amount of bytes to read is the total size or
* up to the segment.stop if present. */
if (stop != -1)
maxsize = MIN (size, stop);
else
maxsize = size;
GST_DEBUG_OBJECT (src,
"reading offset %" G_GUINT64_FORMAT ", length %u, size %" G_GINT64_FORMAT
", segment.stop %" G_GINT64_FORMAT ", maxsize %" G_GINT64_FORMAT, offset,
*length, size, stop, maxsize);
/* check size if we have one */
if (maxsize != -1) {
/* if we run past the end, check if the file became bigger and
* retry. Mind wrap when checking. */
if (G_UNLIKELY (offset >= maxsize || offset + *length >= maxsize || force)) {
/* see if length of the file changed */
if (bclass->get_size)
if (!bclass->get_size (src, &size))
size = -1;
/* make sure we don't exceed the configured segment stop
* if it was set */
if (stop != -1)
maxsize = MIN (size, stop);
else
maxsize = size;
/* if we are at or past the end, EOS */
if (G_UNLIKELY (offset >= maxsize))
goto unexpected_length;
/* else we can clip to the end */
if (G_UNLIKELY (offset + *length >= maxsize))
*length = maxsize - offset;
}
}
/* keep track of current duration.
* segment is in bytes, we checked that above. */
GST_OBJECT_LOCK (src);
src->segment.duration = size;
GST_OBJECT_UNLOCK (src);
return TRUE;
/* ERRORS */
unexpected_length:
{
return FALSE;
}
}
/* must be called with LIVE_LOCK */
static GstFlowReturn
gst_base_src_get_range (GstBaseSrc * src, guint64 offset, guint length,
GstBuffer ** buf)
{
GstFlowReturn ret;
GstBaseSrcClass *bclass;
GstClockReturn status;
GstBuffer *res_buf;
GstBuffer *in_buf;
bclass = GST_BASE_SRC_GET_CLASS (src);
again:
if (src->is_live) {
if (G_UNLIKELY (!src->live_running)) {
ret = gst_base_src_wait_playing (src);
if (ret != GST_FLOW_OK)
goto stopped;
}
}
if (G_UNLIKELY (!GST_BASE_SRC_IS_STARTED (src)
&& !GST_BASE_SRC_IS_STARTING (src)))
goto not_started;
if (G_UNLIKELY (!bclass->create))
goto no_function;
if (G_UNLIKELY (!gst_base_src_update_length (src, offset, &length, FALSE)))
goto unexpected_length;
/* track position */
GST_OBJECT_LOCK (src);
if (src->segment.format == GST_FORMAT_BYTES)
src->segment.position = offset;
GST_OBJECT_UNLOCK (src);
/* normally we don't count buffers */
if (G_UNLIKELY (src->num_buffers_left >= 0)) {
if (src->num_buffers_left == 0)
goto reached_num_buffers;
else
src->num_buffers_left--;
}
/* don't enter the create function if a pending EOS event was set. For the
* logic of the pending_eos, check the event function of this class. */
if (G_UNLIKELY (g_atomic_int_get (&src->priv->pending_eos)))
goto eos;
GST_DEBUG_OBJECT (src,
"calling create offset %" G_GUINT64_FORMAT " length %u, time %"
G_GINT64_FORMAT, offset, length, src->segment.time);
res_buf = in_buf = *buf;
ret = bclass->create (src, offset, length, &res_buf);
/* The create function could be unlocked because we have a pending EOS. It's
* possible that we have a valid buffer from create that we need to
* discard when the create function returned _OK. */
if (G_UNLIKELY (g_atomic_int_get (&src->priv->pending_eos))) {
if (ret == GST_FLOW_OK) {
if (*buf == NULL)
gst_buffer_unref (res_buf);
}
goto eos;
}
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto not_ok;
/* fallback in case the create function didn't fill a provided buffer */
if (in_buf != NULL && res_buf != in_buf) {
GstMapInfo info;
gsize copied_size;
GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, src, "create function didn't "
"fill the provided buffer, copying");
if (!gst_buffer_map (in_buf, &info, GST_MAP_WRITE))
goto map_failed;
copied_size = gst_buffer_extract (res_buf, 0, info.data, info.size);
gst_buffer_unmap (in_buf, &info);
gst_buffer_set_size (in_buf, copied_size);
gst_buffer_copy_into (in_buf, res_buf, GST_BUFFER_COPY_METADATA, 0, -1);
gst_buffer_unref (res_buf);
res_buf = in_buf;
}
/* no timestamp set and we are at offset 0, we can timestamp with 0 */
if (offset == 0 && src->segment.time == 0
&& GST_BUFFER_DTS (res_buf) == -1 && !src->is_live) {
GST_DEBUG_OBJECT (src, "setting first timestamp to 0");
res_buf = gst_buffer_make_writable (res_buf);
GST_BUFFER_DTS (res_buf) = 0;
}
/* now sync before pushing the buffer */
status = gst_base_src_do_sync (src, res_buf);
/* waiting for the clock could have made us flushing */
if (G_UNLIKELY (src->priv->flushing))
goto flushing;
switch (status) {
case GST_CLOCK_EARLY:
/* the buffer is too late. We currently don't drop the buffer. */
GST_DEBUG_OBJECT (src, "buffer too late!, returning anyway");
break;
case GST_CLOCK_OK:
/* buffer synchronised properly */
GST_DEBUG_OBJECT (src, "buffer ok");
break;
case GST_CLOCK_UNSCHEDULED:
/* this case is triggered when we were waiting for the clock and
* it got unlocked because we did a state change. In any case, get rid of
* the buffer. */
if (*buf == NULL)
gst_buffer_unref (res_buf);
if (!src->live_running) {
/* We return FLUSHING when we are not running to stop the dataflow also
* get rid of the produced buffer. */
GST_DEBUG_OBJECT (src,
"clock was unscheduled (%d), returning FLUSHING", status);
ret = GST_FLOW_FLUSHING;
} else {
/* If we are running when this happens, we quickly switched between
* pause and playing. We try to produce a new buffer */
GST_DEBUG_OBJECT (src,
"clock was unscheduled (%d), but we are running", status);
goto again;
}
break;
default:
/* all other result values are unexpected and errors */
GST_ELEMENT_ERROR (src, CORE, CLOCK,
(_("Internal clock error.")),
("clock returned unexpected return value %d", status));
if (*buf == NULL)
gst_buffer_unref (res_buf);
ret = GST_FLOW_ERROR;
break;
}
if (G_LIKELY (ret == GST_FLOW_OK))
*buf = res_buf;
return ret;
/* ERROR */
stopped:
{
GST_DEBUG_OBJECT (src, "wait_playing returned %d (%s)", ret,
gst_flow_get_name (ret));
return ret;
}
not_ok:
{
GST_DEBUG_OBJECT (src, "create returned %d (%s)", ret,
gst_flow_get_name (ret));
return ret;
}
map_failed:
{
GST_ELEMENT_ERROR (src, RESOURCE, BUSY,
(_("Failed to map buffer.")),
("failed to map result buffer in WRITE mode"));
if (*buf == NULL)
gst_buffer_unref (res_buf);
return GST_FLOW_ERROR;
}
not_started:
{
GST_DEBUG_OBJECT (src, "getrange but not started");
return GST_FLOW_FLUSHING;
}
no_function:
{
GST_DEBUG_OBJECT (src, "no create function");
return GST_FLOW_NOT_SUPPORTED;
}
unexpected_length:
{
GST_DEBUG_OBJECT (src, "unexpected length %u (offset=%" G_GUINT64_FORMAT
", size=%" G_GINT64_FORMAT ")", length, offset, src->segment.duration);
return GST_FLOW_EOS;
}
reached_num_buffers:
{
GST_DEBUG_OBJECT (src, "sent all buffers");
return GST_FLOW_EOS;
}
flushing:
{
GST_DEBUG_OBJECT (src, "we are flushing");
if (*buf == NULL)
gst_buffer_unref (res_buf);
return GST_FLOW_FLUSHING;
}
eos:
{
GST_DEBUG_OBJECT (src, "we are EOS");
return GST_FLOW_EOS;
}
}
static GstFlowReturn
gst_base_src_getrange (GstPad * pad, GstObject * parent, guint64 offset,
guint length, GstBuffer ** buf)
{
GstBaseSrc *src;
GstFlowReturn res;
src = GST_BASE_SRC_CAST (parent);
GST_LIVE_LOCK (src);
if (G_UNLIKELY (src->priv->flushing))
goto flushing;
res = gst_base_src_get_range (src, offset, length, buf);
done:
GST_LIVE_UNLOCK (src);
return res;
/* ERRORS */
flushing:
{
GST_DEBUG_OBJECT (src, "we are flushing");
res = GST_FLOW_FLUSHING;
goto done;
}
}
static gboolean
gst_base_src_is_random_access (GstBaseSrc * src)
{
/* we need to start the basesrc to check random access */
if (!GST_BASE_SRC_IS_STARTED (src)) {
GST_LOG_OBJECT (src, "doing start/stop to check get_range support");
if (G_LIKELY (gst_base_src_start (src))) {
if (gst_base_src_start_wait (src) != GST_FLOW_OK)
goto start_failed;
gst_base_src_stop (src);
}
}
return src->random_access;
/* ERRORS */
start_failed:
{
GST_DEBUG_OBJECT (src, "failed to start");
return FALSE;
}
}
static void
gst_base_src_loop (GstPad * pad)
{
GstBaseSrc *src;
GstBuffer *buf = NULL;
GstFlowReturn ret;
gint64 position;
gboolean eos;
guint blocksize;
GList *pending_events = NULL, *tmp;
eos = FALSE;
src = GST_BASE_SRC (GST_OBJECT_PARENT (pad));
/* Just leave immediately if we're flushing */
GST_LIVE_LOCK (src);
if (G_UNLIKELY (src->priv->flushing || GST_PAD_IS_FLUSHING (pad)))
goto flushing;
GST_LIVE_UNLOCK (src);
gst_base_src_send_stream_start (src);
/* The stream-start event could've caused something to flush us */
GST_LIVE_LOCK (src);
if (G_UNLIKELY (src->priv->flushing || GST_PAD_IS_FLUSHING (pad)))
goto flushing;
GST_LIVE_UNLOCK (src);
/* check if we need to renegotiate */
if (gst_pad_check_reconfigure (pad)) {
if (!gst_base_src_negotiate (src)) {
gst_pad_mark_reconfigure (pad);
if (GST_PAD_IS_FLUSHING (pad))
goto flushing;
else
goto negotiate_failed;
}
}
GST_LIVE_LOCK (src);
if (G_UNLIKELY (src->priv->flushing || GST_PAD_IS_FLUSHING (pad)))
goto flushing;
blocksize = src->blocksize;
/* if we operate in bytes, we can calculate an offset */
if (src->segment.format == GST_FORMAT_BYTES) {
position = src->segment.position;
/* for negative rates, start with subtracting the blocksize */
if (src->segment.rate < 0.0) {
/* we cannot go below segment.start */
if (position > src->segment.start + blocksize)
position -= blocksize;
else {
/* last block, remainder up to segment.start */
blocksize = position - src->segment.start;
position = src->segment.start;
}
}
} else
position = -1;
GST_LOG_OBJECT (src, "next_ts %" GST_TIME_FORMAT " size %u",
GST_TIME_ARGS (position), blocksize);
ret = gst_base_src_get_range (src, position, blocksize, &buf);
if (G_UNLIKELY (ret != GST_FLOW_OK)) {
GST_INFO_OBJECT (src, "pausing after gst_base_src_get_range() = %s",
gst_flow_get_name (ret));
GST_LIVE_UNLOCK (src);
goto pause;
}
/* this should not happen */
if (G_UNLIKELY (buf == NULL))
goto null_buffer;
/* push events to close/start our segment before we push the buffer. */
if (G_UNLIKELY (src->priv->segment_pending)) {
GstEvent *seg_event = gst_event_new_segment (&src->segment);
gst_event_set_seqnum (seg_event, src->priv->segment_seqnum);
src->priv->segment_seqnum = gst_util_seqnum_next ();
gst_pad_push_event (pad, seg_event);
src->priv->segment_pending = FALSE;
}
if (g_atomic_int_get (&src->priv->have_events)) {
GST_OBJECT_LOCK (src);
/* take the events */
pending_events = src->priv->pending_events;
src->priv->pending_events = NULL;
g_atomic_int_set (&src->priv->have_events, FALSE);
GST_OBJECT_UNLOCK (src);
}
/* Push out pending events if any */
if (G_UNLIKELY (pending_events != NULL)) {
for (tmp = pending_events; tmp; tmp = g_list_next (tmp)) {
GstEvent *ev = (GstEvent *) tmp->data;
gst_pad_push_event (pad, ev);
}
g_list_free (pending_events);
}
/* figure out the new position */
switch (src->segment.format) {
case GST_FORMAT_BYTES:
{
guint bufsize = gst_buffer_get_size (buf);
/* we subtracted above for negative rates */
if (src->segment.rate >= 0.0)
position += bufsize;
break;
}
case GST_FORMAT_TIME:
{
GstClockTime start, duration;
start = GST_BUFFER_TIMESTAMP (buf);
duration = GST_BUFFER_DURATION (buf);
if (GST_CLOCK_TIME_IS_VALID (start))
position = start;
else
position = src->segment.position;
if (GST_CLOCK_TIME_IS_VALID (duration)) {
if (src->segment.rate >= 0.0)
position += duration;
else if (position > duration)
position -= duration;
else
position = 0;
}
break;
}
case GST_FORMAT_DEFAULT:
if (src->segment.rate >= 0.0)
position = GST_BUFFER_OFFSET_END (buf);
else
position = GST_BUFFER_OFFSET (buf);
break;
default:
position = -1;
break;
}
if (position != -1) {
if (src->segment.rate >= 0.0) {
/* positive rate, check if we reached the stop */
if (src->segment.stop != -1) {
if (position >= src->segment.stop) {
eos = TRUE;
position = src->segment.stop;
}
}
} else {
/* negative rate, check if we reached the start. start is always set to
* something different from -1 */
if (position <= src->segment.start) {
eos = TRUE;
position = src->segment.start;
}
/* when going reverse, all buffers are DISCONT */
src->priv->discont = TRUE;
}
GST_OBJECT_LOCK (src);
src->segment.position = position;
GST_OBJECT_UNLOCK (src);
}
if (G_UNLIKELY (src->priv->discont)) {
GST_INFO_OBJECT (src, "marking pending DISCONT");
buf = gst_buffer_make_writable (buf);
GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DISCONT);
src->priv->discont = FALSE;
}
GST_LIVE_UNLOCK (src);
ret = gst_pad_push (pad, buf);
if (G_UNLIKELY (ret != GST_FLOW_OK)) {
if (ret == GST_FLOW_NOT_NEGOTIATED) {
goto not_negotiated;
}
GST_INFO_OBJECT (src, "pausing after gst_pad_push() = %s",
gst_flow_get_name (ret));
goto pause;
}
if (G_UNLIKELY (eos)) {
GST_INFO_OBJECT (src, "pausing after end of segment");
ret = GST_FLOW_EOS;
goto pause;
}
done:
return;
/* special cases */
not_negotiated:
{
if (gst_pad_needs_reconfigure (pad)) {
GST_DEBUG_OBJECT (src, "Retrying to renegotiate");
return;
}
/* fallthrough when push returns NOT_NEGOTIATED and we don't have
* a pending negotiation request on our srcpad */
}
negotiate_failed:
{
GST_DEBUG_OBJECT (src, "Not negotiated");
ret = GST_FLOW_NOT_NEGOTIATED;
goto pause;
}
flushing:
{
GST_DEBUG_OBJECT (src, "we are flushing");
GST_LIVE_UNLOCK (src);
ret = GST_FLOW_FLUSHING;
goto pause;
}
pause:
{
const gchar *reason = gst_flow_get_name (ret);
GstEvent *event;
GST_DEBUG_OBJECT (src, "pausing task, reason %s", reason);
src->running = FALSE;
gst_pad_pause_task (pad);
if (ret == GST_FLOW_EOS) {
gboolean flag_segment;
GstFormat format;
gint64 position;
/* perform EOS logic */
flag_segment = (src->segment.flags & GST_SEGMENT_FLAG_SEGMENT) != 0;
format = src->segment.format;
position = src->segment.position;
if (flag_segment) {
GstMessage *message;
message = gst_message_new_segment_done (GST_OBJECT_CAST (src),
format, position);
gst_message_set_seqnum (message, src->priv->seqnum);
gst_element_post_message (GST_ELEMENT_CAST (src), message);
event = gst_event_new_segment_done (format, position);
gst_event_set_seqnum (event, src->priv->seqnum);
gst_pad_push_event (pad, event);
} else {
event = gst_event_new_eos ();
gst_event_set_seqnum (event, src->priv->seqnum);
gst_pad_push_event (pad, event);
}
} else if (ret == GST_FLOW_NOT_LINKED || ret <= GST_FLOW_EOS) {
event = gst_event_new_eos ();
gst_event_set_seqnum (event, src->priv->seqnum);
/* for fatal errors we post an error message, post the error
* first so the app knows about the error first.
* Also don't do this for FLUSHING because it happens
* due to flushing and posting an error message because of
* that is the wrong thing to do, e.g. when we're doing
* a flushing seek. */
GST_ELEMENT_ERROR (src, STREAM, FAILED,
(_("Internal data flow error.")),
("streaming task paused, reason %s (%d)", reason, ret));
gst_pad_push_event (pad, event);
}
goto done;
}
null_buffer:
{
GST_ELEMENT_ERROR (src, STREAM, FAILED,
(_("Internal data flow error.")), ("element returned NULL buffer"));
GST_LIVE_UNLOCK (src);
goto done;
}
}
static gboolean
gst_base_src_set_allocation (GstBaseSrc * basesrc, GstBufferPool * pool,
GstAllocator * allocator, GstAllocationParams * params)
{
GstAllocator *oldalloc;
GstBufferPool *oldpool;
GstBaseSrcPrivate *priv = basesrc->priv;
if (pool) {
GST_DEBUG_OBJECT (basesrc, "activate pool");
if (!gst_buffer_pool_set_active (pool, TRUE))
goto activate_failed;
}
GST_OBJECT_LOCK (basesrc);
oldpool = priv->pool;
priv->pool = pool;
oldalloc = priv->allocator;
priv->allocator = allocator;
if (params)
priv->params = *params;
else
gst_allocation_params_init (&priv->params);
GST_OBJECT_UNLOCK (basesrc);
if (oldpool) {
/* only deactivate if the pool is not the one we're using */
if (oldpool != pool) {
GST_DEBUG_OBJECT (basesrc, "deactivate old pool");
gst_buffer_pool_set_active (oldpool, FALSE);
}
gst_object_unref (oldpool);
}
if (oldalloc) {
gst_object_unref (oldalloc);
}
return TRUE;
/* ERRORS */
activate_failed:
{
GST_ERROR_OBJECT (basesrc, "failed to activate bufferpool.");
return FALSE;
}
}
static gboolean
gst_base_src_activate_pool (GstBaseSrc * basesrc, gboolean active)
{
GstBaseSrcPrivate *priv = basesrc->priv;
GstBufferPool *pool;
gboolean res = TRUE;
GST_OBJECT_LOCK (basesrc);
if ((pool = priv->pool))
pool = gst_object_ref (pool);
GST_OBJECT_UNLOCK (basesrc);
if (pool) {
res = gst_buffer_pool_set_active (pool, active);
gst_object_unref (pool);
}
return res;
}
static gboolean
gst_base_src_decide_allocation_default (GstBaseSrc * basesrc, GstQuery * query)
{
GstCaps *outcaps;
GstBufferPool *pool;
guint size, min, max;
GstAllocator *allocator;
GstAllocationParams params;
GstStructure *config;
gboolean update_allocator;
gst_query_parse_allocation (query, &outcaps, NULL);
/* we got configuration from our peer or the decide_allocation method,
* parse them */
if (gst_query_get_n_allocation_params (query) > 0) {
/* try the allocator */
gst_query_parse_nth_allocation_param (query, 0, &allocator, &params);
update_allocator = TRUE;
} else {
allocator = NULL;
gst_allocation_params_init (&params);
update_allocator = FALSE;
}
if (gst_query_get_n_allocation_pools (query) > 0) {
gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
if (pool == NULL) {
/* no pool, we can make our own */
GST_DEBUG_OBJECT (basesrc, "no pool, making new pool");
pool = gst_buffer_pool_new ();
}
} else {
pool = NULL;
size = min = max = 0;
}
/* now configure */
if (pool) {
config = gst_buffer_pool_get_config (pool);
gst_buffer_pool_config_set_params (config, outcaps, size, min, max);
gst_buffer_pool_config_set_allocator (config, allocator, &params);
gst_buffer_pool_set_config (pool, config);
}
if (update_allocator)
gst_query_set_nth_allocation_param (query, 0, allocator, &params);
else
gst_query_add_allocation_param (query, allocator, &params);
if (allocator)
gst_object_unref (allocator);
if (pool) {
gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
gst_object_unref (pool);
}
return TRUE;
}
static gboolean
gst_base_src_prepare_allocation (GstBaseSrc * basesrc, GstCaps * caps)
{
GstBaseSrcClass *bclass;
gboolean result = TRUE;
GstQuery *query;
GstBufferPool *pool = NULL;
GstAllocator *allocator = NULL;
GstAllocationParams params;
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
/* make query and let peer pad answer, we don't really care if it worked or
* not, if it failed, the allocation query would contain defaults and the
* subclass would then set better values if needed */
query = gst_query_new_allocation (caps, TRUE);
if (!gst_pad_peer_query (basesrc->srcpad, query)) {
/* not a problem, just debug a little */
GST_DEBUG_OBJECT (basesrc, "peer ALLOCATION query failed");
}
g_assert (bclass->decide_allocation != NULL);
result = bclass->decide_allocation (basesrc, query);
GST_DEBUG_OBJECT (basesrc, "ALLOCATION (%d) params: %" GST_PTR_FORMAT, result,
query);
if (!result)
goto no_decide_allocation;
/* we got configuration from our peer or the decide_allocation method,
* parse them */
if (gst_query_get_n_allocation_params (query) > 0) {
gst_query_parse_nth_allocation_param (query, 0, &allocator, &params);
} else {
allocator = NULL;
gst_allocation_params_init (&params);
}
if (gst_query_get_n_allocation_pools (query) > 0)
gst_query_parse_nth_allocation_pool (query, 0, &pool, NULL, NULL, NULL);
result = gst_base_src_set_allocation (basesrc, pool, allocator, &params);
gst_query_unref (query);
return result;
/* Errors */
no_decide_allocation:
{
GST_WARNING_OBJECT (basesrc, "Subclass failed to decide allocation");
gst_query_unref (query);
return result;
}
}
/* default negotiation code.
*
* Take intersection between src and sink pads, take first
* caps and fixate.
*/
static gboolean
gst_base_src_default_negotiate (GstBaseSrc * basesrc)
{
GstCaps *thiscaps;
GstCaps *caps = NULL;
GstCaps *peercaps = NULL;
gboolean result = FALSE;
/* first see what is possible on our source pad */
thiscaps = gst_pad_query_caps (GST_BASE_SRC_PAD (basesrc), NULL);
GST_DEBUG_OBJECT (basesrc, "caps of src: %" GST_PTR_FORMAT, thiscaps);
/* nothing or anything is allowed, we're done */
if (thiscaps == NULL || gst_caps_is_any (thiscaps))
goto no_nego_needed;
if (G_UNLIKELY (gst_caps_is_empty (thiscaps)))
goto no_caps;
/* get the peer caps */
peercaps = gst_pad_peer_query_caps (GST_BASE_SRC_PAD (basesrc), thiscaps);
GST_DEBUG_OBJECT (basesrc, "caps of peer: %" GST_PTR_FORMAT, peercaps);
if (peercaps) {
/* The result is already a subset of our caps */
caps = peercaps;
gst_caps_unref (thiscaps);
} else {
/* no peer, work with our own caps then */
caps = thiscaps;
}
if (caps && !gst_caps_is_empty (caps)) {
/* now fixate */
GST_DEBUG_OBJECT (basesrc, "have caps: %" GST_PTR_FORMAT, caps);
if (gst_caps_is_any (caps)) {
GST_DEBUG_OBJECT (basesrc, "any caps, we stop");
/* hmm, still anything, so element can do anything and
* nego is not needed */
result = TRUE;
} else {
caps = gst_base_src_fixate (basesrc, caps);
GST_DEBUG_OBJECT (basesrc, "fixated to: %" GST_PTR_FORMAT, caps);
if (gst_caps_is_fixed (caps)) {
/* yay, fixed caps, use those then, it's possible that the subclass does
* not accept this caps after all and we have to fail. */
result = gst_base_src_set_caps (basesrc, caps);
}
}
gst_caps_unref (caps);
} else {
if (caps)
gst_caps_unref (caps);
GST_DEBUG_OBJECT (basesrc, "no common caps");
}
return result;
no_nego_needed:
{
GST_DEBUG_OBJECT (basesrc, "no negotiation needed");
if (thiscaps)
gst_caps_unref (thiscaps);
return TRUE;
}
no_caps:
{
GST_ELEMENT_ERROR (basesrc, STREAM, FORMAT,
("No supported formats found"),
("This element did not produce valid caps"));
if (thiscaps)
gst_caps_unref (thiscaps);
return TRUE;
}
}
static gboolean
gst_base_src_negotiate (GstBaseSrc * basesrc)
{
GstBaseSrcClass *bclass;
gboolean result;
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
GST_DEBUG_OBJECT (basesrc, "starting negotiation");
if (G_LIKELY (bclass->negotiate))
result = bclass->negotiate (basesrc);
else
result = TRUE;
if (G_LIKELY (result)) {
GstCaps *caps;
caps = gst_pad_get_current_caps (basesrc->srcpad);
result = gst_base_src_prepare_allocation (basesrc, caps);
if (caps)
gst_caps_unref (caps);
}
return result;
}
static gboolean
gst_base_src_start (GstBaseSrc * basesrc)
{
GstBaseSrcClass *bclass;
gboolean result;
GST_LIVE_LOCK (basesrc);
GST_OBJECT_LOCK (basesrc);
if (GST_BASE_SRC_IS_STARTING (basesrc))
goto was_starting;
if (GST_BASE_SRC_IS_STARTED (basesrc))
goto was_started;
basesrc->priv->start_result = GST_FLOW_FLUSHING;
GST_OBJECT_FLAG_SET (basesrc, GST_BASE_SRC_FLAG_STARTING);
gst_segment_init (&basesrc->segment, basesrc->segment.format);
GST_OBJECT_UNLOCK (basesrc);
basesrc->num_buffers_left = basesrc->num_buffers;
basesrc->running = FALSE;
basesrc->priv->segment_pending = FALSE;
basesrc->priv->segment_seqnum = gst_util_seqnum_next ();
GST_LIVE_UNLOCK (basesrc);
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
if (bclass->start)
result = bclass->start (basesrc);
else
result = TRUE;
if (!result)
goto could_not_start;
if (!gst_base_src_is_async (basesrc)) {
gst_base_src_start_complete (basesrc, GST_FLOW_OK);
/* not really waiting here, we call this to get the result
* from the start_complete call */
result = gst_base_src_start_wait (basesrc) == GST_FLOW_OK;
}
return result;
/* ERROR */
was_starting:
{
GST_DEBUG_OBJECT (basesrc, "was starting");
GST_OBJECT_UNLOCK (basesrc);
GST_LIVE_UNLOCK (basesrc);
return TRUE;
}
was_started:
{
GST_DEBUG_OBJECT (basesrc, "was started");
GST_OBJECT_UNLOCK (basesrc);
GST_LIVE_UNLOCK (basesrc);
return TRUE;
}
could_not_start:
{
GST_DEBUG_OBJECT (basesrc, "could not start");
/* subclass is supposed to post a message. We don't have to call _stop. */
gst_base_src_start_complete (basesrc, GST_FLOW_ERROR);
return FALSE;
}
}
/**
* gst_base_src_start_complete:
* @basesrc: base source instance
* @ret: a #GstFlowReturn
*
* Complete an asynchronous start operation. When the subclass overrides the
* start method, it should call gst_base_src_start_complete() when the start
* operation completes either from the same thread or from an asynchronous
* helper thread.
*/
void
gst_base_src_start_complete (GstBaseSrc * basesrc, GstFlowReturn ret)
{
gboolean have_size;
guint64 size;
gboolean seekable;
GstFormat format;
GstPadMode mode;
GstEvent *event;
if (ret != GST_FLOW_OK)
goto error;
GST_DEBUG_OBJECT (basesrc, "starting source");
format = basesrc->segment.format;
/* figure out the size */
have_size = FALSE;
size = -1;
if (format == GST_FORMAT_BYTES) {
GstBaseSrcClass *bclass = GST_BASE_SRC_GET_CLASS (basesrc);
if (bclass->get_size) {
if (!(have_size = bclass->get_size (basesrc, &size)))
size = -1;
}
GST_DEBUG_OBJECT (basesrc, "setting size %" G_GUINT64_FORMAT, size);
/* only update the size when operating in bytes, subclass is supposed
* to set duration in the start method for other formats */
GST_OBJECT_LOCK (basesrc);
basesrc->segment.duration = size;
GST_OBJECT_UNLOCK (basesrc);
}
GST_DEBUG_OBJECT (basesrc,
"format: %s, have size: %d, size: %" G_GUINT64_FORMAT ", duration: %"
G_GINT64_FORMAT, gst_format_get_name (format), have_size, size,
basesrc->segment.duration);
seekable = gst_base_src_seekable (basesrc);
GST_DEBUG_OBJECT (basesrc, "is seekable: %d", seekable);
/* update for random access flag */
basesrc->random_access = seekable && format == GST_FORMAT_BYTES;
GST_DEBUG_OBJECT (basesrc, "is random_access: %d", basesrc->random_access);
/* stop flushing now but for live sources, still block in the LIVE lock when
* we are not yet PLAYING */
gst_base_src_set_flushing (basesrc, FALSE, FALSE, NULL);
gst_pad_mark_reconfigure (GST_BASE_SRC_PAD (basesrc));
GST_OBJECT_LOCK (basesrc->srcpad);
mode = GST_PAD_MODE (basesrc->srcpad);
GST_OBJECT_UNLOCK (basesrc->srcpad);
/* take the stream lock here, we only want to let the task run when we have
* set the STARTED flag */
GST_PAD_STREAM_LOCK (basesrc->srcpad);
if (mode == GST_PAD_MODE_PUSH) {
/* do initial seek, which will start the task */
GST_OBJECT_LOCK (basesrc);
event = basesrc->pending_seek;
basesrc->pending_seek = NULL;
GST_OBJECT_UNLOCK (basesrc);
/* The perform seek code will start the task when finished. We don't have to
* unlock the streaming thread because it is not running yet */
if (G_UNLIKELY (!gst_base_src_perform_seek (basesrc, event, FALSE)))
goto seek_failed;
if (event)
gst_event_unref (event);
} else {
/* if not random_access, we cannot operate in pull mode for now */
if (G_UNLIKELY (!basesrc->random_access))
goto no_get_range;
}
GST_OBJECT_LOCK (basesrc);
GST_OBJECT_FLAG_SET (basesrc, GST_BASE_SRC_FLAG_STARTED);
GST_OBJECT_FLAG_UNSET (basesrc, GST_BASE_SRC_FLAG_STARTING);
basesrc->priv->start_result = ret;
GST_ASYNC_SIGNAL (basesrc);
GST_OBJECT_UNLOCK (basesrc);
GST_PAD_STREAM_UNLOCK (basesrc->srcpad);
return;
seek_failed:
{
GST_PAD_STREAM_UNLOCK (basesrc->srcpad);
GST_ERROR_OBJECT (basesrc, "Failed to perform initial seek");
gst_base_src_stop (basesrc);
if (event)
gst_event_unref (event);
ret = GST_FLOW_ERROR;
goto error;
}
no_get_range:
{
GST_PAD_STREAM_UNLOCK (basesrc->srcpad);
gst_base_src_stop (basesrc);
GST_ERROR_OBJECT (basesrc, "Cannot operate in pull mode, stopping");
ret = GST_FLOW_ERROR;
goto error;
}
error:
{
GST_OBJECT_LOCK (basesrc);
basesrc->priv->start_result = ret;
GST_OBJECT_FLAG_UNSET (basesrc, GST_BASE_SRC_FLAG_STARTING);
GST_ASYNC_SIGNAL (basesrc);
GST_OBJECT_UNLOCK (basesrc);
return;
}
}
/**
* gst_base_src_start_wait:
* @basesrc: base source instance
*
* Wait until the start operation completes.
*
* Returns: a #GstFlowReturn.
*/
GstFlowReturn
gst_base_src_start_wait (GstBaseSrc * basesrc)
{
GstFlowReturn result;
GST_OBJECT_LOCK (basesrc);
while (GST_BASE_SRC_IS_STARTING (basesrc)) {
GST_ASYNC_WAIT (basesrc);
}
result = basesrc->priv->start_result;
GST_OBJECT_UNLOCK (basesrc);
GST_DEBUG_OBJECT (basesrc, "got %s", gst_flow_get_name (result));
return result;
}
static gboolean
gst_base_src_stop (GstBaseSrc * basesrc)
{
GstBaseSrcClass *bclass;
gboolean result = TRUE;
GST_DEBUG_OBJECT (basesrc, "stopping source");
/* flush all */
gst_base_src_set_flushing (basesrc, TRUE, FALSE, NULL);
/* stop the task */
gst_pad_stop_task (basesrc->srcpad);
GST_OBJECT_LOCK (basesrc);
if (!GST_BASE_SRC_IS_STARTED (basesrc) && !GST_BASE_SRC_IS_STARTING (basesrc))
goto was_stopped;
GST_OBJECT_FLAG_UNSET (basesrc, GST_BASE_SRC_FLAG_STARTING);
GST_OBJECT_FLAG_UNSET (basesrc, GST_BASE_SRC_FLAG_STARTED);
basesrc->priv->start_result = GST_FLOW_FLUSHING;
GST_ASYNC_SIGNAL (basesrc);
GST_OBJECT_UNLOCK (basesrc);
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
if (bclass->stop)
result = bclass->stop (basesrc);
gst_base_src_set_allocation (basesrc, NULL, NULL, NULL);
return result;
was_stopped:
{
GST_DEBUG_OBJECT (basesrc, "was stopped");
GST_OBJECT_UNLOCK (basesrc);
return TRUE;
}
}
/* start or stop flushing dataprocessing
*/
static gboolean
gst_base_src_set_flushing (GstBaseSrc * basesrc,
gboolean flushing, gboolean live_play, gboolean * playing)
{
GstBaseSrcClass *bclass;
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
GST_DEBUG_OBJECT (basesrc, "flushing %d, live_play %d", flushing, live_play);
if (flushing) {
gst_base_src_activate_pool (basesrc, FALSE);
/* unlock any subclasses, we need to do this before grabbing the
* LIVE_LOCK since we hold this lock before going into ::create. We pass an
* unlock to the params because of backwards compat (see seek handler)*/
if (bclass->unlock)
bclass->unlock (basesrc);
}
/* the live lock is released when we are blocked, waiting for playing or
* when we sync to the clock. */
GST_LIVE_LOCK (basesrc);
if (playing)
*playing = basesrc->live_running;
basesrc->priv->flushing = flushing;
if (flushing) {
/* if we are locked in the live lock, signal it to make it flush */
basesrc->live_running = TRUE;
/* clear pending EOS if any */
g_atomic_int_set (&basesrc->priv->pending_eos, FALSE);
/* step 1, now that we have the LIVE lock, clear our unlock request */
if (bclass->unlock_stop)
bclass->unlock_stop (basesrc);
/* step 2, unblock clock sync (if any) or any other blocking thing */
if (basesrc->clock_id)
gst_clock_id_unschedule (basesrc->clock_id);
} else {
/* signal the live source that it can start playing */
basesrc->live_running = live_play;
gst_base_src_activate_pool (basesrc, TRUE);
/* Drop all delayed events */
GST_OBJECT_LOCK (basesrc);
if (basesrc->priv->pending_events) {
g_list_foreach (basesrc->priv->pending_events, (GFunc) gst_event_unref,
NULL);
g_list_free (basesrc->priv->pending_events);
basesrc->priv->pending_events = NULL;
g_atomic_int_set (&basesrc->priv->have_events, FALSE);
}
GST_OBJECT_UNLOCK (basesrc);
}
GST_LIVE_SIGNAL (basesrc);
GST_LIVE_UNLOCK (basesrc);
return TRUE;
}
/* the purpose of this function is to make sure that a live source blocks in the
* LIVE lock or leaves the LIVE lock and continues playing. */
static gboolean
gst_base_src_set_playing (GstBaseSrc * basesrc, gboolean live_play)
{
GstBaseSrcClass *bclass;
bclass = GST_BASE_SRC_GET_CLASS (basesrc);
/* unlock subclasses locked in ::create, we only do this when we stop playing. */
if (!live_play) {
GST_DEBUG_OBJECT (basesrc, "unlock");
if (bclass->unlock)
bclass->unlock (basesrc);
}
/* we are now able to grab the LIVE lock, when we get it, we can be
* waiting for PLAYING while blocked in the LIVE cond or we can be waiting
* for the clock. */
GST_LIVE_LOCK (basesrc);
GST_DEBUG_OBJECT (basesrc, "unschedule clock");
/* unblock clock sync (if any) */
if (basesrc->clock_id)
gst_clock_id_unschedule (basesrc->clock_id);
/* configure what to do when we get to the LIVE lock. */
GST_DEBUG_OBJECT (basesrc, "live running %d", live_play);
basesrc->live_running = live_play;
if (live_play) {
gboolean start;
/* clear our unlock request when going to PLAYING */
GST_DEBUG_OBJECT (basesrc, "unlock stop");
if (bclass->unlock_stop)
bclass->unlock_stop (basesrc);
/* for live sources we restart the timestamp correction */
basesrc->priv->latency = -1;
/* have to restart the task in case it stopped because of the unlock when
* we went to PAUSED. Only do this if we operating in push mode. */
GST_OBJECT_LOCK (basesrc->srcpad);
start = (GST_PAD_MODE (basesrc->srcpad) == GST_PAD_MODE_PUSH);
GST_OBJECT_UNLOCK (basesrc->srcpad);
if (start)
gst_pad_start_task (basesrc->srcpad, (GstTaskFunction) gst_base_src_loop,
basesrc->srcpad, NULL);
GST_DEBUG_OBJECT (basesrc, "signal");
GST_LIVE_SIGNAL (basesrc);
}
GST_LIVE_UNLOCK (basesrc);
return TRUE;
}
static gboolean
gst_base_src_activate_push (GstPad * pad, GstObject * parent, gboolean active)
{
GstBaseSrc *basesrc;
basesrc = GST_BASE_SRC (parent);
/* prepare subclass first */
if (active) {
GST_DEBUG_OBJECT (basesrc, "Activating in push mode");
if (G_UNLIKELY (!basesrc->can_activate_push))
goto no_push_activation;
if (G_UNLIKELY (!gst_base_src_start (basesrc)))
goto error_start;
} else {
GST_DEBUG_OBJECT (basesrc, "Deactivating in push mode");
/* now we can stop the source */
if (G_UNLIKELY (!gst_base_src_stop (basesrc)))
goto error_stop;
}
return TRUE;
/* ERRORS */
no_push_activation:
{
GST_WARNING_OBJECT (basesrc, "Subclass disabled push-mode activation");
return FALSE;
}
error_start:
{
GST_WARNING_OBJECT (basesrc, "Failed to start in push mode");
return FALSE;
}
error_stop:
{
GST_DEBUG_OBJECT (basesrc, "Failed to stop in push mode");
return FALSE;
}
}
static gboolean
gst_base_src_activate_pull (GstPad * pad, GstObject * parent, gboolean active)
{
GstBaseSrc *basesrc;
basesrc = GST_BASE_SRC (parent);
/* prepare subclass first */
if (active) {
GST_DEBUG_OBJECT (basesrc, "Activating in pull mode");
if (G_UNLIKELY (!gst_base_src_start (basesrc)))
goto error_start;
} else {
GST_DEBUG_OBJECT (basesrc, "Deactivating in pull mode");
if (G_UNLIKELY (!gst_base_src_stop (basesrc)))
goto error_stop;
}
return TRUE;
/* ERRORS */
error_start:
{
GST_ERROR_OBJECT (basesrc, "Failed to start in pull mode");
return FALSE;
}
error_stop:
{
GST_ERROR_OBJECT (basesrc, "Failed to stop in pull mode");
return FALSE;
}
}
static gboolean
gst_base_src_activate_mode (GstPad * pad, GstObject * parent,
GstPadMode mode, gboolean active)
{
gboolean res;
GstBaseSrc *src = GST_BASE_SRC (parent);
src->priv->stream_start_pending = FALSE;
switch (mode) {
case GST_PAD_MODE_PULL:
res = gst_base_src_activate_pull (pad, parent, active);
break;
case GST_PAD_MODE_PUSH:
src->priv->stream_start_pending = active;
res = gst_base_src_activate_push (pad, parent, active);
break;
default:
GST_LOG_OBJECT (pad, "unknown activation mode %d", mode);
res = FALSE;
break;
}
return res;
}
static GstStateChangeReturn
gst_base_src_change_state (GstElement * element, GstStateChange transition)
{
GstBaseSrc *basesrc;
GstStateChangeReturn result;
gboolean no_preroll = FALSE;
basesrc = GST_BASE_SRC (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
no_preroll = gst_base_src_is_live (basesrc);
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
GST_DEBUG_OBJECT (basesrc, "PAUSED->PLAYING");
if (gst_base_src_is_live (basesrc)) {
/* now we can start playback */
gst_base_src_set_playing (basesrc, TRUE);
}
break;
default:
break;
}
if ((result =
GST_ELEMENT_CLASS (parent_class)->change_state (element,
transition)) == GST_STATE_CHANGE_FAILURE)
goto failure;
switch (transition) {
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
GST_DEBUG_OBJECT (basesrc, "PLAYING->PAUSED");
if (gst_base_src_is_live (basesrc)) {
/* make sure we block in the live lock in PAUSED */
gst_base_src_set_playing (basesrc, FALSE);
no_preroll = TRUE;
}
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
{
/* we don't need to unblock anything here, the pad deactivation code
* already did this */
g_atomic_int_set (&basesrc->priv->pending_eos, FALSE);
gst_event_replace (&basesrc->pending_seek, NULL);
break;
}
case GST_STATE_CHANGE_READY_TO_NULL:
break;
default:
break;
}
if (no_preroll && result == GST_STATE_CHANGE_SUCCESS)
result = GST_STATE_CHANGE_NO_PREROLL;
return result;
/* ERRORS */
failure:
{
GST_DEBUG_OBJECT (basesrc, "parent failed state change");
return result;
}
}
/**
* gst_base_src_get_buffer_pool:
* @src: a #GstBaseSrc
*
* Returns: (transfer full): the instance of the #GstBufferPool used
* by the src; free it after use it
*/
GstBufferPool *
gst_base_src_get_buffer_pool (GstBaseSrc * src)
{
g_return_val_if_fail (GST_IS_BASE_SRC (src), NULL);
if (src->priv->pool)
return gst_object_ref (src->priv->pool);
return NULL;
}
/**
* gst_base_src_get_allocator:
* @src: a #GstBaseSrc
* @allocator: (out) (allow-none) (transfer full): the #GstAllocator
* used
* @params: (out) (allow-none) (transfer full): the
* #GstAllocationParams of @allocator
*
* Lets #GstBaseSrc sub-classes to know the memory @allocator
* used by the base class and its @params.
*
* Unref the @allocator after use it.
*/
void
gst_base_src_get_allocator (GstBaseSrc * src,
GstAllocator ** allocator, GstAllocationParams * params)
{
g_return_if_fail (GST_IS_BASE_SRC (src));
if (allocator)
*allocator = src->priv->allocator ?
gst_object_ref (src->priv->allocator) : NULL;
if (params)
*params = src->priv->params;
}
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