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DEFINITIONS
This source file includes following definitions.
- gst_bin_base_init
- gst_bin_child_proxy_get_child_by_index
- gst_bin_child_proxy_get_children_count
- gst_bin_child_proxy_init
- _gst_boolean_accumulator
- gst_bin_class_init
- gst_bin_init
- gst_bin_dispose
- gst_bin_new
- gst_bin_set_property
- gst_bin_get_property
- gst_bin_get_index_func
- gst_bin_set_index_func
- gst_bin_set_clock_func
- gst_bin_provide_clock_func
- message_check
- find_message
- bin_replace_message
- bin_remove_messages
- is_eos
- unlink_pads
- gst_bin_add_func
- gst_bin_add
- gst_bin_remove_func
- gst_bin_remove
- iterate_child
- gst_bin_iterate_elements
- iterate_child_recurse
- gst_bin_iterate_recurse
- bin_element_is_sink
- sink_iterator_filter
- gst_bin_iterate_sinks
- bin_element_is_src
- src_iterator_filter
- gst_bin_iterate_sources
- gst_bin_get_state_func
- add_to_queue
- remove_from_queue
- clear_queue
- reset_degree
- update_degree
- find_element
- gst_bin_sort_iterator_next
- gst_bin_sort_iterator_resync
- gst_bin_sort_iterator_free
- gst_bin_sort_iterator_new
- gst_bin_iterate_sorted
- gst_bin_element_set_state
- activate_pads
- iterator_activate_fold_with_resync
- gst_bin_src_pads_activate
- gst_bin_recalculate_latency
- gst_bin_do_latency_func
- gst_bin_change_state_func
- gst_bin_send_event
- gst_bin_continue_func
- bin_bus_handler
- bin_push_state_continue
- bin_handle_async_start
- bin_handle_async_done
- gst_bin_handle_message_func
- bin_query_min_max_init
- bin_query_duration_fold
- bin_query_duration_done
- bin_query_position_fold
- bin_query_position_done
- bin_query_latency_fold
- bin_query_latency_done
- bin_query_generic_fold
- gst_bin_query
- compare_name
- gst_bin_get_by_name
- gst_bin_get_by_name_recurse_up
- compare_interface
- gst_bin_get_by_interface
- gst_bin_iterate_all_by_interface
- gst_bin_save_thyself
- gst_bin_restore_thyself
/* GStreamer
*
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2004 Wim Taymans <wim.taymans@gmail.com>
*
* gstbin.c: GstBin container object and support code
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* MT safe.
*/
/**
* SECTION:gstbin
* @short_description: Base class and element that can contain other elements
*
* #GstBin is an element that can contain other #GstElement, allowing them to be
* managed as a group.
* Pads from the child elements can be ghosted to the bin, see #GstGhostPad.
* This makes the bin look like any other elements and enables creation of
* higher-level abstraction elements.
*
* A new #GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you
* want to create a toplevel bin because a normal bin doesn't have a bus or
* handle clock distribution of its own.
*
* After the bin has been created you will typically add elements to it with
* gst_bin_add(). You can remove elements with gst_bin_remove().
*
* An element can be retrieved from a bin with gst_bin_get_by_name(), using the
* elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
* purposes and will query the parent bins when the element is not found in the
* current bin.
*
* An iterator of elements in a bin can be retrieved with
* gst_bin_iterate_elements(). Various other iterators exist to retrieve the
* elements in a bin.
*
* gst_object_unref() is used to drop your reference to the bin.
*
* The #GstBin::element-added signal is fired whenever a new element is added to
* the bin. Likewise the #GstBin::element-removed signal is fired whenever an
* element is removed from the bin.
*
* <refsect2><title>Notes</title>
* <para>
* A #GstBin internally intercepts every #GstMessage posted by its children and
* implements the following default behaviour for each of them:
* <variablelist>
* <varlistentry>
* <term>GST_MESSAGE_EOS</term>
* <listitem><para>This message is only posted by sinks in the PLAYING
* state. If all sinks posted the EOS message, this bin will post and EOS
* message upwards.</para></listitem>
* </varlistentry>
* <varlistentry>
* <term>GST_MESSAGE_SEGMENT_START</term>
* <listitem><para>just collected and never forwarded upwards.
* The messages are used to decide when all elements have completed playback
* of their segment.</para></listitem>
* </varlistentry>
* <varlistentry>
* <term>GST_MESSAGE_SEGMENT_DONE</term>
* <listitem><para> Is posted by #GstBin when all elements that posted
* a SEGMENT_START have posted a SEGMENT_DONE.</para></listitem>
* </varlistentry>
* <varlistentry>
* <term>GST_MESSAGE_DURATION</term>
* <listitem><para> Is posted by an element that detected a change
* in the stream duration. The default bin behaviour is to clear any
* cached duration values so that the next duration query will perform
* a full duration recalculation. The duration change is posted to the
* application so that it can refetch the new duration with a duration
* query. Note that these messages can be posted before the bin is
* prerolled, in which case the duration query might fail.
* </para></listitem>
* </varlistentry>
* <varlistentry>
* <term>GST_MESSAGE_CLOCK_LOST</term>
* <listitem><para> This message is posted by an element when it
* can no longer provide a clock. The default bin behaviour is to
* check if the lost clock was the one provided by the bin. If so and
* the bin is currently in the PLAYING state, the message is forwarded to
* the bin parent.
* This message is also generated when a clock provider is removed from
* the bin. If this message is received by the application, it should
* PAUSE the pipeline and set it back to PLAYING to force a new clock
* distribution.
* </para></listitem>
* </varlistentry>
* <varlistentry>
* <term>GST_MESSAGE_CLOCK_PROVIDE</term>
* <listitem><para> This message is generated when an element
* can provide a clock. This mostly happens when a new clock
* provider is added to the bin. The default behaviour of the bin is to
* mark the currently selected clock as dirty, which will perform a clock
* recalculation the next time the bin is asked to provide a clock.
* This message is never sent tot the application but is forwarded to
* the parent of the bin.
* </para></listitem>
* </varlistentry>
* <varlistentry>
* <term>OTHERS</term>
* <listitem><para> posted upwards.</para></listitem>
* </varlistentry>
* </variablelist>
*
*
* A #GstBin implements the following default behaviour for answering to a
* #GstQuery:
* <variablelist>
* <varlistentry>
* <term>GST_QUERY_DURATION</term>
* <listitem><para>If the query has been asked before with the same format
* and the bin is a toplevel bin (ie. has no parent),
* use the cached previous value. If no previous value was cached, the
* query is sent to all sink elements in the bin and the MAXIMUM of all
* values is returned. If the bin is a toplevel bin the value is cached.
* If no sinks are available in the bin, the query fails.
* </para></listitem>
* </varlistentry>
* <varlistentry>
* <term>GST_QUERY_POSITION</term>
* <listitem><para>The query is sent to all sink elements in the bin and the
* MAXIMUM of all values is returned. If no sinks are available in the bin,
* the query fails.
* </para></listitem>
* </varlistentry>
* <varlistentry>
* <term>OTHERS</term>
* <listitem><para>the query is forwarded to all sink elements, the result
* of the first sink that answers the query successfully is returned. If no
* sink is in the bin, the query fails.</para></listitem>
* </varlistentry>
* </variablelist>
*
* A #GstBin will by default forward any event sent to it to all sink elements.
* If all the sinks return TRUE, the bin will also return TRUE, else FALSE is
* returned. If no sinks are in the bin, the event handler will return TRUE.
*
* </para>
* </refsect2>
*
* Last reviewed on 2006-04-28 (0.10.6)
*/
#include "gst_private.h"
#include "gstevent.h"
#include "gstbin.h"
#include "gstmarshal.h"
#include "gstxml.h"
#include "gstinfo.h"
#include "gsterror.h"
#include "gstindex.h"
#include "gstindexfactory.h"
#include "gstutils.h"
#include "gstchildproxy.h"
#ifdef GST_DISABLE_DEPRECATED
#if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
#undef GstXmlNodePtr
#define GstXmlNodePtr xmlNodePtr
#include <libxml/parser.h>
GstXmlNodePtr gst_object_save_thyself (GstObject * object,
GstXmlNodePtr parent);
void gst_object_restore_thyself (GstObject * object, GstXmlNodePtr parent);
GstElement *gst_xml_make_element (xmlNodePtr cur, GstObject * parent);
#endif
#endif
/* enable for DURATION caching.
* FIXME currently too many elements don't update
* their duration when it changes so we return inaccurate values. */
#undef DURATION_CACHING
/* latency is by default enabled now.
* live-preroll and no-live-preroll in the environment var GST_COMPAT
* to enables or disable it respectively.
*/
static gboolean enable_latency = TRUE;
GST_DEBUG_CATEGORY_STATIC (bin_debug);
#define GST_CAT_DEFAULT bin_debug
/* a bin is toplevel if it has no parent or when it is configured to behave like
* a toplevel bin */
#define BIN_IS_TOPLEVEL(bin) ((GST_OBJECT_PARENT (bin) == NULL) || bin->priv->asynchandling)
#define GST_BIN_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_BIN, GstBinPrivate))
struct _GstBinPrivate
{
gboolean asynchandling;
/* if we get an ASYNC_DONE message from ourselves, this means that the
* subclass will simulate ASYNC behaviour without having ASYNC children. When
* such an ASYNC_DONE message is posted while we are doing a state change, we
* have to process the message after finishing the state change even when no
* child returned GST_STATE_CHANGE_ASYNC. */
gboolean pending_async_done;
guint32 structure_cookie;
/* cached index */
GstIndex *index;
};
typedef struct
{
GstBin *bin;
guint32 cookie;
GstState pending;
} BinContinueData;
static void gst_bin_dispose (GObject * object);
static void gst_bin_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_bin_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstStateChangeReturn gst_bin_change_state_func (GstElement * element,
GstStateChange transition);
static GstStateChangeReturn gst_bin_get_state_func (GstElement * element,
GstState * state, GstState * pending, GstClockTime timeout);
static void bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
gboolean flag_pending);
static void bin_handle_async_start (GstBin * bin, gboolean new_base_time);
static void bin_push_state_continue (BinContinueData * data);
static gboolean gst_bin_add_func (GstBin * bin, GstElement * element);
static gboolean gst_bin_remove_func (GstBin * bin, GstElement * element);
static void gst_bin_set_index_func (GstElement * element, GstIndex * index);
static GstIndex *gst_bin_get_index_func (GstElement * element);
static GstClock *gst_bin_provide_clock_func (GstElement * element);
static gboolean gst_bin_set_clock_func (GstElement * element, GstClock * clock);
static void gst_bin_handle_message_func (GstBin * bin, GstMessage * message);
static gboolean gst_bin_send_event (GstElement * element, GstEvent * event);
static GstBusSyncReply bin_bus_handler (GstBus * bus,
GstMessage * message, GstBin * bin);
static gboolean gst_bin_query (GstElement * element, GstQuery * query);
static gboolean gst_bin_do_latency_func (GstBin * bin);
#if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
static xmlNodePtr gst_bin_save_thyself (GstObject * object, xmlNodePtr parent);
static void gst_bin_restore_thyself (GstObject * object, xmlNodePtr self);
#endif
static void bin_remove_messages (GstBin * bin, GstObject * src,
GstMessageType types);
static void gst_bin_continue_func (BinContinueData * data);
static gint bin_element_is_sink (GstElement * child, GstBin * bin);
static gint bin_element_is_src (GstElement * child, GstBin * bin);
static GstIterator *gst_bin_sort_iterator_new (GstBin * bin);
/* Bin signals and properties */
enum
{
ELEMENT_ADDED,
ELEMENT_REMOVED,
DO_LATENCY,
LAST_SIGNAL
};
#define DEFAULT_ASYNC_HANDLING FALSE
enum
{
PROP_0,
PROP_ASYNC_HANDLING
/* FILL ME */
};
static void gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data);
static guint gst_bin_signals[LAST_SIGNAL] = { 0 };
#define _do_init(type) \
{ \
const gchar *compat; \
static const GInterfaceInfo iface_info = { \
gst_bin_child_proxy_init, \
NULL, \
NULL}; \
\
g_type_add_interface_static (type, GST_TYPE_CHILD_PROXY, &iface_info); \
\
GST_DEBUG_CATEGORY_INIT (bin_debug, "bin", GST_DEBUG_BOLD, \
"debugging info for the 'bin' container element"); \
\
/* compatibility stuff */ \
compat = g_getenv ("GST_COMPAT"); \
if (compat != NULL) { \
if (strstr (compat, "no-live-preroll")) \
enable_latency = FALSE; \
else if (strstr (compat, "live-preroll")) \
enable_latency = TRUE; \
} \
}
GST_BOILERPLATE_FULL (GstBin, gst_bin, GstElement, GST_TYPE_ELEMENT, _do_init);
static void
gst_bin_base_init (gpointer g_class)
{
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_set_details_simple (gstelement_class, "Generic bin",
"Generic/Bin",
"Simple container object",
"Erik Walthinsen <omega@cse.ogi.edu>,"
"Wim Taymans <wim.taymans@gmail.com>");
}
static GstObject *
gst_bin_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
guint index)
{
GstObject *res;
GstBin *bin;
bin = GST_BIN_CAST (child_proxy);
GST_OBJECT_LOCK (bin);
if ((res = g_list_nth_data (bin->children, index)))
gst_object_ref (res);
GST_OBJECT_UNLOCK (bin);
return res;
}
static guint
gst_bin_child_proxy_get_children_count (GstChildProxy * child_proxy)
{
guint num;
GstBin *bin;
bin = GST_BIN_CAST (child_proxy);
GST_OBJECT_LOCK (bin);
num = bin->numchildren;
GST_OBJECT_UNLOCK (bin);
return num;
}
static void
gst_bin_child_proxy_init (gpointer g_iface, gpointer iface_data)
{
GstChildProxyInterface *iface = g_iface;
iface->get_children_count = gst_bin_child_proxy_get_children_count;
iface->get_child_by_index = gst_bin_child_proxy_get_child_by_index;
}
static gboolean
_gst_boolean_accumulator (GSignalInvocationHint * ihint,
GValue * return_accu, const GValue * handler_return, gpointer dummy)
{
gboolean myboolean;
myboolean = g_value_get_boolean (handler_return);
if (!(ihint->run_type & G_SIGNAL_RUN_CLEANUP))
g_value_set_boolean (return_accu, myboolean);
GST_DEBUG ("invocation %d, %d", ihint->run_type, myboolean);
/* stop emission */
return FALSE;
}
static void
gst_bin_class_init (GstBinClass * klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
GstElementClass *gstelement_class;
GError *err;
gobject_class = (GObjectClass *) klass;
gstobject_class = (GstObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
g_type_class_add_private (klass, sizeof (GstBinPrivate));
gobject_class->set_property = gst_bin_set_property;
gobject_class->get_property = gst_bin_get_property;
/**
* GstBin:async-handling
*
* If set to #TRUE, the bin will handle asynchronous state changes.
* This should be used only if the bin subclass is modifying the state
* of its children on its own.
*
* Since: 0.10.13
*/
g_object_class_install_property (gobject_class, PROP_ASYNC_HANDLING,
g_param_spec_boolean ("async-handling", "Async Handling",
"The bin will handle Asynchronous state changes",
DEFAULT_ASYNC_HANDLING, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/**
* GstBin::element-added:
* @bin: the #GstBin
* @element: the #GstElement that was added to the bin
*
* Will be emitted after the element was added to the bin.
*/
gst_bin_signals[ELEMENT_ADDED] =
g_signal_new ("element-added", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_added), NULL,
NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
/**
* GstBin::element-removed:
* @bin: the #GstBin
* @element: the #GstElement that was removed from the bin
*
* Will be emitted after the element was removed from the bin.
*/
gst_bin_signals[ELEMENT_REMOVED] =
g_signal_new ("element-removed", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_FIRST, G_STRUCT_OFFSET (GstBinClass, element_removed), NULL,
NULL, gst_marshal_VOID__OBJECT, G_TYPE_NONE, 1, GST_TYPE_ELEMENT);
/**
* GstBin::do-latency:
* @bin: the #GstBin
*
* Will be emitted when the bin needs to perform latency calculations. This
* signal is only emited for toplevel bins or when async-handling is
* enabled.
*
* Only one signal handler is invoked. If no signals are connected, the
* default handler is invoked, which will query and distribute the lowest
* possible latency to all sinks.
*
* Connect to this signal if the default latency calculations are not
* sufficient, like when you need different latencies for different sinks in
* the same pipeline.
*
* Since: 0.10.22
*/
gst_bin_signals[DO_LATENCY] =
g_signal_new ("do-latency", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstBinClass, do_latency),
_gst_boolean_accumulator, NULL, gst_marshal_BOOLEAN__VOID,
G_TYPE_BOOLEAN, 0, G_TYPE_NONE);
gobject_class->dispose = gst_bin_dispose;
#if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
gstobject_class->save_thyself =
((gpointer (*)(GstObject * object,
gpointer self)) * GST_DEBUG_FUNCPTR (gst_bin_save_thyself));
gstobject_class->restore_thyself =
((void (*)(GstObject * object,
gpointer self)) *GST_DEBUG_FUNCPTR (gst_bin_restore_thyself));
#endif
gstelement_class->change_state =
GST_DEBUG_FUNCPTR (gst_bin_change_state_func);
gstelement_class->get_state = GST_DEBUG_FUNCPTR (gst_bin_get_state_func);
gstelement_class->get_index = GST_DEBUG_FUNCPTR (gst_bin_get_index_func);
gstelement_class->set_index = GST_DEBUG_FUNCPTR (gst_bin_set_index_func);
gstelement_class->provide_clock =
GST_DEBUG_FUNCPTR (gst_bin_provide_clock_func);
gstelement_class->set_clock = GST_DEBUG_FUNCPTR (gst_bin_set_clock_func);
gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_bin_send_event);
gstelement_class->query = GST_DEBUG_FUNCPTR (gst_bin_query);
klass->add_element = GST_DEBUG_FUNCPTR (gst_bin_add_func);
klass->remove_element = GST_DEBUG_FUNCPTR (gst_bin_remove_func);
klass->handle_message = GST_DEBUG_FUNCPTR (gst_bin_handle_message_func);
klass->do_latency = GST_DEBUG_FUNCPTR (gst_bin_do_latency_func);
GST_DEBUG ("creating bin thread pool");
err = NULL;
klass->pool =
g_thread_pool_new ((GFunc) gst_bin_continue_func, NULL, -1, FALSE, &err);
if (err != NULL) {
g_critical ("could alloc threadpool %s", err->message);
}
}
static void
gst_bin_init (GstBin * bin, GstBinClass * klass)
{
GstBus *bus;
bin->numchildren = 0;
bin->children = NULL;
bin->children_cookie = 0;
bin->messages = NULL;
bin->provided_clock = NULL;
bin->clock_dirty = FALSE;
/* Set up a bus for listening to child elements */
bus = gst_bus_new ();
bin->child_bus = bus;
GST_DEBUG_OBJECT (bin, "using bus %" GST_PTR_FORMAT " to listen to children",
bus);
gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bin_bus_handler, bin);
bin->priv = GST_BIN_GET_PRIVATE (bin);
bin->priv->asynchandling = DEFAULT_ASYNC_HANDLING;
bin->priv->structure_cookie = 0;
}
static void
gst_bin_dispose (GObject * object)
{
GstBin *bin = GST_BIN_CAST (object);
GstBus **child_bus_p = &bin->child_bus;
GstClock **provided_clock_p = &bin->provided_clock;
GstElement **clock_provider_p = &bin->clock_provider;
GstIndex **index_p = &bin->priv->index;
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, object, "dispose");
GST_OBJECT_LOCK (object);
gst_object_replace ((GstObject **) child_bus_p, NULL);
gst_object_replace ((GstObject **) provided_clock_p, NULL);
gst_object_replace ((GstObject **) clock_provider_p, NULL);
gst_object_replace ((GstObject **) index_p, NULL);
bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
GST_OBJECT_UNLOCK (object);
while (bin->children) {
gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
}
if (G_UNLIKELY (bin->children != NULL)) {
g_critical ("could not remove elements from bin %s",
GST_STR_NULL (GST_OBJECT_NAME (object)));
}
G_OBJECT_CLASS (parent_class)->dispose (object);
}
/**
* gst_bin_new:
* @name: the name of the new bin
*
* Creates a new bin with the given name.
*
* Returns: a new #GstBin
*/
GstElement *
gst_bin_new (const gchar * name)
{
return gst_element_factory_make ("bin", name);
}
static void
gst_bin_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstBin *gstbin;
gstbin = GST_BIN_CAST (object);
switch (prop_id) {
case PROP_ASYNC_HANDLING:
GST_OBJECT_LOCK (gstbin);
gstbin->priv->asynchandling = g_value_get_boolean (value);
GST_OBJECT_UNLOCK (gstbin);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_bin_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstBin *gstbin;
gstbin = GST_BIN_CAST (object);
switch (prop_id) {
case PROP_ASYNC_HANDLING:
GST_OBJECT_LOCK (gstbin);
g_value_set_boolean (value, gstbin->priv->asynchandling);
GST_OBJECT_UNLOCK (gstbin);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* return the cached index */
static GstIndex *
gst_bin_get_index_func (GstElement * element)
{
GstBin *bin;
GstIndex *result;
bin = GST_BIN_CAST (element);
GST_OBJECT_LOCK (bin);
if ((result = bin->priv->index))
gst_object_ref (result);
GST_OBJECT_UNLOCK (bin);
return result;
}
/* set the index on all elements in this bin
*
* MT safe
*/
static void
gst_bin_set_index_func (GstElement * element, GstIndex * index)
{
GstBin *bin;
gboolean done;
GstIterator *it;
GstIndex *old;
bin = GST_BIN_CAST (element);
GST_OBJECT_LOCK (bin);
old = bin->priv->index;
if (G_UNLIKELY (old == index))
goto was_set;
if (index)
gst_object_ref (index);
bin->priv->index = index;
GST_OBJECT_UNLOCK (bin);
if (old)
gst_object_unref (old);
it = gst_bin_iterate_elements (bin);
/* set the index on all elements in the bin */
done = FALSE;
while (!done) {
gpointer data;
switch (gst_iterator_next (it, &data)) {
case GST_ITERATOR_OK:
{
GstElement *child = GST_ELEMENT_CAST (data);
GST_DEBUG_OBJECT (bin, "setting index on %s", GST_ELEMENT_NAME (child));
gst_element_set_index (child, index);
gst_object_unref (child);
break;
}
case GST_ITERATOR_RESYNC:
GST_DEBUG_OBJECT (bin, "iterator doing resync");
gst_iterator_resync (it);
break;
default:
case GST_ITERATOR_DONE:
GST_DEBUG_OBJECT (bin, "iterator done");
done = TRUE;
break;
}
}
gst_iterator_free (it);
return;
was_set:
{
GST_DEBUG_OBJECT (bin, "index was already set");
GST_OBJECT_UNLOCK (bin);
return;
}
}
/* set the clock on all elements in this bin
*
* MT safe
*/
static gboolean
gst_bin_set_clock_func (GstElement * element, GstClock * clock)
{
GstBin *bin;
gboolean done;
GstIterator *it;
gboolean res = TRUE;
bin = GST_BIN_CAST (element);
it = gst_bin_iterate_elements (bin);
done = FALSE;
while (!done) {
gpointer data;
switch (gst_iterator_next (it, &data)) {
case GST_ITERATOR_OK:
{
GstElement *child = GST_ELEMENT_CAST (data);
res &= gst_element_set_clock (child, clock);
gst_object_unref (child);
break;
}
case GST_ITERATOR_RESYNC:
GST_DEBUG_OBJECT (bin, "iterator doing resync");
gst_iterator_resync (it);
res = TRUE;
break;
default:
case GST_ITERATOR_DONE:
GST_DEBUG_OBJECT (bin, "iterator done");
done = TRUE;
break;
}
}
gst_iterator_free (it);
return res;
}
/* get the clock for this bin by asking all of the children in this bin
*
* The ref of the returned clock in increased so unref after usage.
*
* We loop the elements in state order and pick the last clock we can
* get. This makes sure we get a clock from the source.
*
* MT safe
*/
static GstClock *
gst_bin_provide_clock_func (GstElement * element)
{
GstClock *result = NULL;
GstElement *provider = NULL;
GstBin *bin;
GstIterator *it;
gpointer val;
GstClock **provided_clock_p;
GstElement **clock_provider_p;
bin = GST_BIN_CAST (element);
GST_OBJECT_LOCK (bin);
if (!bin->clock_dirty)
goto not_dirty;
GST_DEBUG_OBJECT (bin, "finding new clock");
it = gst_bin_sort_iterator_new (bin);
while (it->next (it, &val) == GST_ITERATOR_OK) {
GstElement *child = GST_ELEMENT_CAST (val);
GstClock *clock;
clock = gst_element_provide_clock (child);
if (clock) {
GST_DEBUG_OBJECT (bin, "found candidate clock %p by element %s",
clock, GST_ELEMENT_NAME (child));
if (result) {
gst_object_unref (result);
gst_object_unref (provider);
}
result = clock;
provider = child;
} else {
gst_object_unref (child);
}
}
provided_clock_p = &bin->provided_clock;
clock_provider_p = &bin->clock_provider;
gst_object_replace ((GstObject **) provided_clock_p, (GstObject *) result);
gst_object_replace ((GstObject **) clock_provider_p, (GstObject *) provider);
bin->clock_dirty = FALSE;
GST_DEBUG_OBJECT (bin,
"provided new clock %" GST_PTR_FORMAT " by provider %" GST_PTR_FORMAT,
result, provider);
/* Provider is not being returned to caller, just the result */
if (provider)
gst_object_unref (provider);
GST_OBJECT_UNLOCK (bin);
gst_iterator_free (it);
return result;
not_dirty:
{
if ((result = bin->provided_clock))
gst_object_ref (result);
GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
GST_OBJECT_UNLOCK (bin);
return result;
}
}
/*
* functions for manipulating cached messages
*/
typedef struct
{
GstObject *src;
GstMessageType types;
} MessageFind;
/* check if a message is of given src and type */
static gint
message_check (GstMessage * message, MessageFind * target)
{
gboolean eq = TRUE;
if (target->src)
eq &= GST_MESSAGE_SRC (message) == target->src;
if (target->types)
eq &= (GST_MESSAGE_TYPE (message) & target->types) != 0;
GST_LOG ("looking at message %p: %d", message, eq);
return (eq ? 0 : 1);
}
static GList *
find_message (GstBin * bin, GstObject * src, GstMessageType types)
{
GList *result;
MessageFind find;
find.src = src;
find.types = types;
result = g_list_find_custom (bin->messages, &find,
(GCompareFunc) message_check);
if (result) {
GST_DEBUG_OBJECT (bin, "we found a message %p from %s matching types %08x",
result->data, GST_OBJECT_NAME (GST_MESSAGE_CAST (result->data)->src),
types);
} else {
GST_DEBUG_OBJECT (bin, "no message found matching types %08x", types);
#ifndef GST_DISABLE_GST_DEBUG
{
guint i;
for (i = 0; i < 32; i++)
if (types & (1 << i))
GST_DEBUG_OBJECT (bin, " %s", gst_message_type_get_name (1 << i));
}
#endif
}
return result;
}
/* with LOCK, returns TRUE if message had a valid SRC, takes ownership of
* the message.
*
* A message that is cached and has the same SRC and type is replaced
* by the given message.
*/
static gboolean
bin_replace_message (GstBin * bin, GstMessage * message, GstMessageType types)
{
GList *previous;
GstObject *src;
gboolean res = TRUE;
if ((src = GST_MESSAGE_SRC (message))) {
/* first find the previous message posted by this element */
if ((previous = find_message (bin, src, types))) {
GstMessage *previous_msg;
/* if we found a previous message, replace it */
previous_msg = previous->data;
previous->data = message;
GST_DEBUG_OBJECT (bin, "replace old message %s from %s with %s message",
GST_MESSAGE_TYPE_NAME (previous_msg), GST_ELEMENT_NAME (src),
GST_MESSAGE_TYPE_NAME (message));
gst_message_unref (previous_msg);
} else {
/* keep new message */
bin->messages = g_list_prepend (bin->messages, message);
GST_DEBUG_OBJECT (bin, "got new message %p, %s from %s",
message, GST_MESSAGE_TYPE_NAME (message), GST_ELEMENT_NAME (src));
}
} else {
GST_DEBUG_OBJECT (bin, "got message %s from (NULL), not processing",
GST_MESSAGE_TYPE_NAME (message));
res = FALSE;
gst_message_unref (message);
}
return res;
}
/* with LOCK. Remove all messages of given types */
static void
bin_remove_messages (GstBin * bin, GstObject * src, GstMessageType types)
{
MessageFind find;
GList *walk, *next;
find.src = src;
find.types = types;
for (walk = bin->messages; walk; walk = next) {
GstMessage *message = (GstMessage *) walk->data;
next = g_list_next (walk);
if (message_check (message, &find) == 0) {
GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
"deleting message %p of types 0x%08x", message, types);
bin->messages = g_list_delete_link (bin->messages, walk);
gst_message_unref (message);
} else {
GST_DEBUG_OBJECT (GST_MESSAGE_SRC (message),
"not deleting message %p of type 0x%08x", message,
GST_MESSAGE_TYPE (message));
}
}
}
/* Check if the bin is EOS. We do this by scanning all sinks and
* checking if they posted an EOS message.
*
* call with bin LOCK */
static gboolean
is_eos (GstBin * bin)
{
gboolean result;
GList *walk;
result = TRUE;
for (walk = bin->children; walk; walk = g_list_next (walk)) {
GstElement *element;
element = GST_ELEMENT_CAST (walk->data);
if (bin_element_is_sink (element, bin) == 0) {
/* check if element posted EOS */
if (find_message (bin, GST_OBJECT_CAST (element), GST_MESSAGE_EOS)) {
GST_DEBUG ("sink '%s' posted EOS", GST_ELEMENT_NAME (element));
} else {
GST_DEBUG ("sink '%s' did not post EOS yet",
GST_ELEMENT_NAME (element));
result = FALSE;
break;
}
}
}
return result;
}
static void
unlink_pads (GstPad * pad)
{
GstPad *peer;
if ((peer = gst_pad_get_peer (pad))) {
if (gst_pad_get_direction (pad) == GST_PAD_SRC)
gst_pad_unlink (pad, peer);
else
gst_pad_unlink (peer, pad);
gst_object_unref (peer);
}
gst_object_unref (pad);
}
/* vmethod that adds an element to a bin
*
* MT safe
*/
static gboolean
gst_bin_add_func (GstBin * bin, GstElement * element)
{
gchar *elem_name;
GstIterator *it;
gboolean is_sink;
GstMessage *clock_message = NULL, *async_message = NULL;
GstStateChangeReturn ret;
GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
/* we obviously can't add ourself to ourself */
if (G_UNLIKELY (GST_ELEMENT_CAST (element) == GST_ELEMENT_CAST (bin)))
goto adding_itself;
/* get the element name to make sure it is unique in this bin. */
GST_OBJECT_LOCK (element);
elem_name = g_strdup (GST_ELEMENT_NAME (element));
is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_IS_SINK);
GST_OBJECT_UNLOCK (element);
GST_OBJECT_LOCK (bin);
/* then check to see if the element's name is already taken in the bin,
* we can safely take the lock here. This check is probably bogus because
* you can safely change the element name after this check and before setting
* the object parent. The window is very small though... */
if (G_UNLIKELY (!gst_object_check_uniqueness (bin->children, elem_name)))
goto duplicate_name;
/* set the element's parent and add the element to the bin's list of children */
if (G_UNLIKELY (!gst_object_set_parent (GST_OBJECT_CAST (element),
GST_OBJECT_CAST (bin))))
goto had_parent;
/* if we add a sink we become a sink */
if (is_sink) {
GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "element \"%s\" was sink",
elem_name);
GST_OBJECT_FLAG_SET (bin, GST_ELEMENT_IS_SINK);
}
if (gst_element_provides_clock (element)) {
GST_DEBUG_OBJECT (bin, "element \"%s\" can provide a clock", elem_name);
clock_message =
gst_message_new_clock_provide (GST_OBJECT_CAST (element), NULL, TRUE);
}
bin->children = g_list_prepend (bin->children, element);
bin->numchildren++;
bin->children_cookie++;
bin->priv->structure_cookie++;
/* distribute the bus */
gst_element_set_bus (element, bin->child_bus);
/* propagate the current base_time, start_time and clock */
gst_element_set_base_time (element, GST_ELEMENT_CAST (bin)->base_time);
gst_element_set_start_time (element, GST_ELEMENT_START_TIME (bin));
/* it's possible that the element did not accept the clock but
* that is not important right now. When the pipeline goes to PLAYING,
* a new clock will be selected */
gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
/* set the cached index on the children */
if (bin->priv->index)
gst_element_set_index (element, bin->priv->index);
ret = GST_STATE_RETURN (bin);
/* no need to update the state if we are in error */
if (ret == GST_STATE_CHANGE_FAILURE)
goto no_state_recalc;
/* update the bin state, the new element could have been an ASYNC or
* NO_PREROLL element */
ret = GST_STATE_RETURN (element);
GST_DEBUG_OBJECT (bin, "added %s element",
gst_element_state_change_return_get_name (ret));
switch (ret) {
case GST_STATE_CHANGE_ASYNC:
{
/* create message to track this aync element when it posts an async-done
* message */
async_message =
gst_message_new_async_start (GST_OBJECT_CAST (element), FALSE);
break;
}
case GST_STATE_CHANGE_NO_PREROLL:
/* ignore all async elements we might have and commit our state */
bin_handle_async_done (bin, ret, FALSE);
break;
case GST_STATE_CHANGE_FAILURE:
break;
default:
break;
}
no_state_recalc:
GST_OBJECT_UNLOCK (bin);
/* post the messages on the bus of the element so that the bin can handle
* them */
if (clock_message)
gst_element_post_message (GST_ELEMENT_CAST (element), clock_message);
if (async_message)
gst_element_post_message (GST_ELEMENT_CAST (element), async_message);
/* unlink all linked pads */
it = gst_element_iterate_pads (element);
gst_iterator_foreach (it, (GFunc) unlink_pads, element);
gst_iterator_free (it);
GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin, "added element \"%s\"",
elem_name);
g_free (elem_name);
g_signal_emit (bin, gst_bin_signals[ELEMENT_ADDED], 0, element);
gst_child_proxy_child_added ((GstObject *) bin, (GstObject *) element);
return TRUE;
/* ERROR handling here */
adding_itself:
{
GST_OBJECT_LOCK (bin);
g_warning ("Cannot add bin %s to itself", GST_ELEMENT_NAME (bin));
GST_OBJECT_UNLOCK (bin);
return FALSE;
}
duplicate_name:
{
g_warning ("Name %s is not unique in bin %s, not adding",
elem_name, GST_ELEMENT_NAME (bin));
GST_OBJECT_UNLOCK (bin);
g_free (elem_name);
return FALSE;
}
had_parent:
{
g_warning ("Element %s already has parent", elem_name);
GST_OBJECT_UNLOCK (bin);
g_free (elem_name);
return FALSE;
}
}
/**
* gst_bin_add:
* @bin: a #GstBin
* @element: the #GstElement to add
*
* Adds the given element to the bin. Sets the element's parent, and thus
* takes ownership of the element. An element can only be added to one bin.
*
* If the element's pads are linked to other pads, the pads will be unlinked
* before the element is added to the bin.
*
* MT safe.
*
* Returns: TRUE if the element could be added, FALSE if
* the bin does not want to accept the element.
*/
gboolean
gst_bin_add (GstBin * bin, GstElement * element)
{
GstBinClass *bclass;
gboolean result;
g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
bclass = GST_BIN_GET_CLASS (bin);
if (G_UNLIKELY (bclass->add_element == NULL))
goto no_function;
GST_CAT_DEBUG (GST_CAT_PARENTAGE, "adding element %s to bin %s",
GST_STR_NULL (GST_ELEMENT_NAME (element)),
GST_STR_NULL (GST_ELEMENT_NAME (bin)));
result = bclass->add_element (bin, element);
return result;
/* ERROR handling */
no_function:
{
g_warning ("adding elements to bin %s is not supported",
GST_ELEMENT_NAME (bin));
return FALSE;
}
}
/* remove an element from the bin
*
* MT safe
*/
static gboolean
gst_bin_remove_func (GstBin * bin, GstElement * element)
{
gchar *elem_name;
GstIterator *it;
gboolean is_sink, othersink, found;
GstMessage *clock_message = NULL;
GstClock **provided_clock_p;
GstElement **clock_provider_p;
GList *walk, *next;
gboolean other_async, this_async, have_no_preroll;
GstStateChangeReturn ret;
GST_DEBUG_OBJECT (bin, "element :%s", GST_ELEMENT_NAME (element));
GST_OBJECT_LOCK (element);
/* Check if the element is already being removed and immediately
* return */
if (G_UNLIKELY (GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_UNPARENTING)))
goto already_removing;
GST_OBJECT_FLAG_SET (element, GST_ELEMENT_UNPARENTING);
/* grab element name so we can print it */
elem_name = g_strdup (GST_ELEMENT_NAME (element));
is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_IS_SINK);
GST_OBJECT_UNLOCK (element);
/* unlink all linked pads */
it = gst_element_iterate_pads (element);
gst_iterator_foreach (it, (GFunc) unlink_pads, element);
gst_iterator_free (it);
GST_OBJECT_LOCK (bin);
found = FALSE;
othersink = FALSE;
have_no_preroll = FALSE;
/* iterate the elements, we collect which ones are async and no_preroll. We
* also remove the element when we find it. */
for (walk = bin->children; walk; walk = next) {
GstElement *child = GST_ELEMENT_CAST (walk->data);
next = g_list_next (walk);
if (child == element) {
found = TRUE;
/* remove the element */
bin->children = g_list_delete_link (bin->children, walk);
} else {
gboolean child_sink;
GST_OBJECT_LOCK (child);
child_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_IS_SINK);
/* when we remove a sink, check if there are other sinks. */
if (is_sink && !othersink && child_sink)
othersink = TRUE;
/* check if we have NO_PREROLL children */
if (GST_STATE_RETURN (child) == GST_STATE_CHANGE_NO_PREROLL)
have_no_preroll = TRUE;
GST_OBJECT_UNLOCK (child);
}
}
/* the element must have been in the bin's list of children */
if (G_UNLIKELY (!found))
goto not_in_bin;
/* we now removed the element from the list of elements, increment the cookie
* so that others can detect a change in the children list. */
bin->numchildren--;
bin->children_cookie++;
bin->priv->structure_cookie++;
if (is_sink && !othersink) {
/* we're not a sink anymore */
GST_DEBUG_OBJECT (bin, "we removed the last sink");
GST_OBJECT_FLAG_UNSET (bin, GST_ELEMENT_IS_SINK);
}
/* if the clock provider for this element is removed, we lost
* the clock as well, we need to inform the parent of this
* so that it can select a new clock */
if (bin->clock_provider == element) {
GST_DEBUG_OBJECT (bin, "element \"%s\" provided the clock", elem_name);
bin->clock_dirty = TRUE;
clock_message =
gst_message_new_clock_lost (GST_OBJECT_CAST (bin), bin->provided_clock);
provided_clock_p = &bin->provided_clock;
clock_provider_p = &bin->clock_provider;
gst_object_replace ((GstObject **) provided_clock_p, NULL);
gst_object_replace ((GstObject **) clock_provider_p, NULL);
}
/* remove messages for the element, if there was a pending ASYNC_START
* message we must see if removing the element caused the bin to lose its
* async state. */
this_async = FALSE;
other_async = FALSE;
for (walk = bin->messages; walk; walk = next) {
GstMessage *message = (GstMessage *) walk->data;
GstElement *src = GST_ELEMENT_CAST (GST_MESSAGE_SRC (message));
gboolean remove;
next = g_list_next (walk);
remove = FALSE;
switch (GST_MESSAGE_TYPE (message)) {
case GST_MESSAGE_ASYNC_START:
if (src == element)
this_async = TRUE;
else
other_async = TRUE;
GST_DEBUG_OBJECT (src, "looking at message %p", message);
break;
case GST_MESSAGE_STRUCTURE_CHANGE:
{
GstElement *owner;
GST_DEBUG_OBJECT (src, "looking at structure change message %p",
message);
/* it's unlikely that this message is still in the list of messages
* because this would mean that a link/unlink is busy in another thread
* while we remove the element. We still have to remove the message
* because we might not receive the done message anymore when the element
* is removed from the bin. */
gst_message_parse_structure_change (message, NULL, &owner, NULL);
if (owner == element)
remove = TRUE;
break;
}
default:
break;
}
if (src == element)
remove = TRUE;
if (remove) {
/* delete all message types */
GST_DEBUG_OBJECT (src, "deleting message %p of element \"%s\"",
message, elem_name);
bin->messages = g_list_delete_link (bin->messages, walk);
gst_message_unref (message);
}
}
/* get last return */
ret = GST_STATE_RETURN (bin);
/* no need to update the state if we are in error */
if (ret == GST_STATE_CHANGE_FAILURE)
goto no_state_recalc;
if (!other_async && this_async) {
/* all other elements were not async and we removed the async one,
* handle the async-done case because we are not async anymore now. */
GST_DEBUG_OBJECT (bin,
"we removed the last async element, have no_preroll %d",
have_no_preroll);
/* the current state return of the bin depends on if there are no_preroll
* elements in the pipeline or not */
if (have_no_preroll)
ret = GST_STATE_CHANGE_NO_PREROLL;
else
ret = GST_STATE_CHANGE_SUCCESS;
bin_handle_async_done (bin, ret, FALSE);
} else {
GST_DEBUG_OBJECT (bin,
"recalc state preroll: %d, other async: %d, this async %d",
have_no_preroll, other_async, this_async);
if (have_no_preroll) {
ret = GST_STATE_CHANGE_NO_PREROLL;
} else if (other_async) {
/* there are other async elements and we were not doing an async state
* change, change our pending state and go async */
if (GST_STATE_PENDING (bin) == GST_STATE_VOID_PENDING) {
GST_STATE_NEXT (bin) = GST_STATE (bin);
GST_STATE_PENDING (bin) = GST_STATE (bin);
}
ret = GST_STATE_CHANGE_ASYNC;
}
GST_STATE_RETURN (bin) = ret;
}
no_state_recalc:
GST_OBJECT_UNLOCK (bin);
if (clock_message)
gst_element_post_message (GST_ELEMENT_CAST (bin), clock_message);
GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "removed child \"%s\"",
elem_name);
g_free (elem_name);
gst_element_set_bus (element, NULL);
/* Clear the clock we provided to the element */
gst_element_set_clock (element, NULL);
/* we ref here because after the _unparent() the element can be disposed
* and we still need it to reset the UNPARENTING flag and fire a signal. */
gst_object_ref (element);
gst_object_unparent (GST_OBJECT_CAST (element));
GST_OBJECT_LOCK (element);
GST_OBJECT_FLAG_UNSET (element, GST_ELEMENT_UNPARENTING);
GST_OBJECT_UNLOCK (element);
g_signal_emit (bin, gst_bin_signals[ELEMENT_REMOVED], 0, element);
gst_child_proxy_child_removed ((GstObject *) bin, (GstObject *) element);
/* element is really out of our control now */
gst_object_unref (element);
return TRUE;
/* ERROR handling */
not_in_bin:
{
g_warning ("Element %s is not in bin %s", elem_name,
GST_ELEMENT_NAME (bin));
GST_OBJECT_UNLOCK (bin);
g_free (elem_name);
return FALSE;
}
already_removing:
{
GST_CAT_INFO_OBJECT (GST_CAT_PARENTAGE, bin, "already removing child");
GST_OBJECT_UNLOCK (element);
return FALSE;
}
}
/**
* gst_bin_remove:
* @bin: a #GstBin
* @element: the #GstElement to remove
*
* Removes the element from the bin, unparenting it as well.
* Unparenting the element means that the element will be dereferenced,
* so if the bin holds the only reference to the element, the element
* will be freed in the process of removing it from the bin. If you
* want the element to still exist after removing, you need to call
* gst_object_ref() before removing it from the bin.
*
* If the element's pads are linked to other pads, the pads will be unlinked
* before the element is removed from the bin.
*
* MT safe.
*
* Returns: TRUE if the element could be removed, FALSE if
* the bin does not want to remove the element.
*/
gboolean
gst_bin_remove (GstBin * bin, GstElement * element)
{
GstBinClass *bclass;
gboolean result;
g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
g_return_val_if_fail (GST_IS_ELEMENT (element), FALSE);
bclass = GST_BIN_GET_CLASS (bin);
if (G_UNLIKELY (bclass->remove_element == NULL))
goto no_function;
GST_CAT_DEBUG (GST_CAT_PARENTAGE, "removing element %s from bin %s",
GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (bin));
result = bclass->remove_element (bin, element);
return result;
/* ERROR handling */
no_function:
{
g_warning ("removing elements from bin %s is not supported",
GST_ELEMENT_NAME (bin));
return FALSE;
}
}
static GstIteratorItem
iterate_child (GstIterator * it, GstElement * child)
{
gst_object_ref (child);
return GST_ITERATOR_ITEM_PASS;
}
/**
* gst_bin_iterate_elements:
* @bin: a #GstBin
*
* Gets an iterator for the elements in this bin.
*
* Each element yielded by the iterator will have its refcount increased, so
* unref after use.
*
* MT safe. Caller owns returned value.
*
* Returns: a #GstIterator of #GstElement, or NULL
*/
GstIterator *
gst_bin_iterate_elements (GstBin * bin)
{
GstIterator *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
GST_OBJECT_LOCK (bin);
/* add ref because the iterator refs the bin. When the iterator
* is freed it will unref the bin again using the provided dispose
* function. */
gst_object_ref (bin);
result = gst_iterator_new_list (GST_TYPE_ELEMENT,
GST_OBJECT_GET_LOCK (bin),
&bin->children_cookie,
&bin->children,
bin,
(GstIteratorItemFunction) iterate_child,
(GstIteratorDisposeFunction) gst_object_unref);
GST_OBJECT_UNLOCK (bin);
return result;
}
static GstIteratorItem
iterate_child_recurse (GstIterator * it, GstElement * child)
{
gst_object_ref (child);
if (GST_IS_BIN (child)) {
GstIterator *other = gst_bin_iterate_recurse (GST_BIN_CAST (child));
gst_iterator_push (it, other);
}
return GST_ITERATOR_ITEM_PASS;
}
/**
* gst_bin_iterate_recurse:
* @bin: a #GstBin
*
* Gets an iterator for the elements in this bin.
* This iterator recurses into GstBin children.
*
* Each element yielded by the iterator will have its refcount increased, so
* unref after use.
*
* MT safe. Caller owns returned value.
*
* Returns: a #GstIterator of #GstElement, or NULL
*/
GstIterator *
gst_bin_iterate_recurse (GstBin * bin)
{
GstIterator *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
GST_OBJECT_LOCK (bin);
/* add ref because the iterator refs the bin. When the iterator
* is freed it will unref the bin again using the provided dispose
* function. */
gst_object_ref (bin);
result = gst_iterator_new_list (GST_TYPE_ELEMENT,
GST_OBJECT_GET_LOCK (bin),
&bin->children_cookie,
&bin->children,
bin,
(GstIteratorItemFunction) iterate_child_recurse,
(GstIteratorDisposeFunction) gst_object_unref);
GST_OBJECT_UNLOCK (bin);
return result;
}
/* returns 0 when TRUE because this is a GCompareFunc */
/* MT safe */
static gint
bin_element_is_sink (GstElement * child, GstBin * bin)
{
gboolean is_sink;
/* we lock the child here for the remainder of the function to
* get its name and flag safely. */
GST_OBJECT_LOCK (child);
is_sink = GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_IS_SINK);
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
"child %s %s sink", GST_OBJECT_NAME (child), is_sink ? "is" : "is not");
GST_OBJECT_UNLOCK (child);
return is_sink ? 0 : 1;
}
static gint
sink_iterator_filter (GstElement * child, GstBin * bin)
{
if (bin_element_is_sink (child, bin) == 0) {
/* returns 0 because this is a GCompareFunc */
return 0;
} else {
/* child carries a ref from gst_bin_iterate_elements -- drop if not passing
through */
gst_object_unref (child);
return 1;
}
}
/**
* gst_bin_iterate_sinks:
* @bin: a #GstBin
*
* Gets an iterator for all elements in the bin that have the
* #GST_ELEMENT_IS_SINK flag set.
*
* Each element yielded by the iterator will have its refcount increased, so
* unref after use.
*
* MT safe. Caller owns returned value.
*
* Returns: a #GstIterator of #GstElement, or NULL
*/
GstIterator *
gst_bin_iterate_sinks (GstBin * bin)
{
GstIterator *children;
GstIterator *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
children = gst_bin_iterate_elements (bin);
result = gst_iterator_filter (children,
(GCompareFunc) sink_iterator_filter, bin);
return result;
}
/* returns 0 when TRUE because this is a GCompareFunc */
/* MT safe */
static gint
bin_element_is_src (GstElement * child, GstBin * bin)
{
gboolean is_src = FALSE;
/* we lock the child here for the remainder of the function to
* get its name and flag safely. */
GST_OBJECT_LOCK (child);
if (!GST_OBJECT_FLAG_IS_SET (child, GST_ELEMENT_IS_SINK) &&
!child->numsinkpads) {
is_src = TRUE;
}
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
"child %s %s src", GST_OBJECT_NAME (child), is_src ? "is" : "is not");
GST_OBJECT_UNLOCK (child);
return is_src ? 0 : 1;
}
static gint
src_iterator_filter (GstElement * child, GstBin * bin)
{
if (bin_element_is_src (child, bin) == 0) {
/* returns 0 because this is a GCompareFunc */
return 0;
} else {
/* child carries a ref from gst_bin_iterate_elements -- drop if not passing
through */
gst_object_unref (child);
return 1;
}
}
/**
* gst_bin_iterate_sources:
* @bin: a #GstBin
*
* Gets an iterator for all elements in the bin that have no sinkpads and have
* the #GST_ELEMENT_IS_SINK flag unset.
*
* Each element yielded by the iterator will have its refcount increased, so
* unref after use.
*
* MT safe. Caller owns returned value.
*
* Returns: a #GstIterator of #GstElement, or NULL
*/
GstIterator *
gst_bin_iterate_sources (GstBin * bin)
{
GstIterator *children;
GstIterator *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
children = gst_bin_iterate_elements (bin);
result = gst_iterator_filter (children,
(GCompareFunc) src_iterator_filter, bin);
return result;
}
/*
* MT safe
*/
static GstStateChangeReturn
gst_bin_get_state_func (GstElement * element, GstState * state,
GstState * pending, GstClockTime timeout)
{
GstStateChangeReturn ret;
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element, "getting state");
ret = parent_class->get_state (element, state, pending, timeout);
return ret;
}
/***********************************************
* Topologically sorted iterator
* see http://en.wikipedia.org/wiki/Topological_sorting
*
* For each element in the graph, an entry is kept in a HashTable
* with its number of srcpad connections (degree).
* We then change state of all elements without dependencies
* (degree 0) and decrement the degree of all elements connected
* on the sinkpads. When an element reaches degree 0, its state is
* changed next.
* When all elements are handled the algorithm stops.
*/
typedef struct _GstBinSortIterator
{
GstIterator it;
GQueue *queue; /* elements queued for state change */
GstBin *bin; /* bin we iterate */
gint mode; /* adding or removing dependency */
GstElement *best; /* next element with least dependencies */
gint best_deg; /* best degree */
GHashTable *hash; /* hashtable with element dependencies */
gboolean dirty; /* we detected structure change */
} GstBinSortIterator;
/* we add and subtract 1 to make sure we don't confuse NULL and 0 */
#define HASH_SET_DEGREE(bit, elem, deg) \
g_hash_table_replace (bit->hash, elem, GINT_TO_POINTER(deg+1))
#define HASH_GET_DEGREE(bit, elem) \
(GPOINTER_TO_INT(g_hash_table_lookup (bit->hash, elem))-1)
/* add element to queue of next elements in the iterator.
* We push at the tail to give higher priority elements a
* chance first */
static void
add_to_queue (GstBinSortIterator * bit, GstElement * element)
{
GST_DEBUG_OBJECT (bit->bin, "adding '%s' to queue",
GST_ELEMENT_NAME (element));
gst_object_ref (element);
g_queue_push_tail (bit->queue, element);
HASH_SET_DEGREE (bit, element, -1);
}
static void
remove_from_queue (GstBinSortIterator * bit, GstElement * element)
{
GList *find;
if ((find = g_queue_find (bit->queue, element))) {
GST_DEBUG_OBJECT (bit->bin, "removing '%s' from queue",
GST_ELEMENT_NAME (element));
g_queue_delete_link (bit->queue, find);
gst_object_unref (element);
} else {
GST_DEBUG_OBJECT (bit->bin, "unable to remove '%s' from queue",
GST_ELEMENT_NAME (element));
}
}
/* clear the queue, unref all objects as we took a ref when
* we added them to the queue */
static void
clear_queue (GQueue * queue)
{
gpointer p;
while ((p = g_queue_pop_head (queue)))
gst_object_unref (p);
}
/* set all degrees to 0. Elements marked as a sink are
* added to the queue immediatly. Since we only look at the SINK flag of the
* element, it is possible that we add non-sinks to the queue. These will be
* removed from the queue again when we can prove that it provides data for some
* other element. */
static void
reset_degree (GstElement * element, GstBinSortIterator * bit)
{
gboolean is_sink;
/* sinks are added right away */
GST_OBJECT_LOCK (element);
is_sink = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_IS_SINK);
GST_OBJECT_UNLOCK (element);
if (is_sink) {
add_to_queue (bit, element);
} else {
/* others are marked with 0 and handled when sinks are done */
HASH_SET_DEGREE (bit, element, 0);
}
}
/* adjust the degree of all elements connected to the given
* element. If a degree of an element drops to 0, it is
* added to the queue of elements to schedule next.
*
* We have to make sure not to cross the bin boundary this element
* belongs to.
*/
static void
update_degree (GstElement * element, GstBinSortIterator * bit)
{
gboolean linked = FALSE;
GST_OBJECT_LOCK (element);
/* don't touch degree if element has no sinkpads */
if (element->numsinkpads != 0) {
/* loop over all sinkpads, decrement degree for all connected
* elements in this bin */
GList *pads;
for (pads = element->sinkpads; pads; pads = g_list_next (pads)) {
GstPad *pad, *peer;
pad = GST_PAD_CAST (pads->data);
/* we're iterating over the sinkpads, check if it's busy in a link/unlink */
if (G_UNLIKELY (find_message (bit->bin, GST_OBJECT_CAST (pad),
GST_MESSAGE_STRUCTURE_CHANGE))) {
/* mark the iterator as dirty because we won't be updating the degree
* of the peer parent now. This would result in the 'loop detected'
* later on because the peer parent element could become the best next
* element with a degree > 0. We will simply continue our state
* changes and we'll eventually resync when the unlink completed and
* the iterator cookie is updated. */
bit->dirty = TRUE;
continue;
}
if ((peer = gst_pad_get_peer (pad))) {
GstElement *peer_element;
if ((peer_element = gst_pad_get_parent_element (peer))) {
GST_OBJECT_LOCK (peer_element);
/* check that we don't go outside of this bin */
if (GST_OBJECT_CAST (peer_element)->parent ==
GST_OBJECT_CAST (bit->bin)) {
gint old_deg, new_deg;
old_deg = HASH_GET_DEGREE (bit, peer_element);
/* check to see if we added an element as sink that was not really a
* sink because it was connected to some other element. */
if (old_deg == -1) {
remove_from_queue (bit, peer_element);
old_deg = 0;
}
new_deg = old_deg + bit->mode;
GST_DEBUG_OBJECT (bit->bin,
"change element %s, degree %d->%d, linked to %s",
GST_ELEMENT_NAME (peer_element), old_deg, new_deg,
GST_ELEMENT_NAME (element));
/* update degree, it is possible that an element was in 0 and
* reaches -1 here. This would mean that the element had no sinkpads
* but became linked while the state change was happening. We will
* resync on this with the structure change message. */
if (new_deg == 0) {
/* degree hit 0, add to queue */
add_to_queue (bit, peer_element);
} else {
HASH_SET_DEGREE (bit, peer_element, new_deg);
}
linked = TRUE;
}
GST_OBJECT_UNLOCK (peer_element);
gst_object_unref (peer_element);
}
gst_object_unref (peer);
}
}
}
if (!linked) {
GST_DEBUG_OBJECT (bit->bin, "element %s not linked on any sinkpads",
GST_ELEMENT_NAME (element));
}
GST_OBJECT_UNLOCK (element);
}
/* find the next best element not handled yet. This is the one
* with the lowest non-negative degree */
static void
find_element (GstElement * element, GstBinSortIterator * bit)
{
gint degree;
/* element is already handled */
if ((degree = HASH_GET_DEGREE (bit, element)) < 0)
return;
/* first element or element with smaller degree */
if (bit->best == NULL || bit->best_deg > degree) {
bit->best = element;
bit->best_deg = degree;
}
}
/* get next element in iterator. the returned element has the
* refcount increased */
static GstIteratorResult
gst_bin_sort_iterator_next (GstBinSortIterator * bit, gpointer * result)
{
GstBin *bin = bit->bin;
/* empty queue, we have to find a next best element */
if (g_queue_is_empty (bit->queue)) {
GstElement *best;
bit->best = NULL;
bit->best_deg = G_MAXINT;
g_list_foreach (bin->children, (GFunc) find_element, bit);
if ((best = bit->best)) {
/* when we detected an unlink, don't warn because our degrees might be
* screwed up. We will resync later */
if (bit->best_deg != 0 && !bit->dirty) {
/* we don't fail on this one yet */
GST_WARNING_OBJECT (bin, "loop dected in graph");
g_warning ("loop detected in the graph of bin %s!!",
GST_ELEMENT_NAME (bin));
}
/* best unhandled element, schedule as next element */
GST_DEBUG_OBJECT (bin, "queue empty, next best: %s",
GST_ELEMENT_NAME (best));
gst_object_ref (best);
HASH_SET_DEGREE (bit, best, -1);
*result = best;
} else {
GST_DEBUG_OBJECT (bin, "queue empty, elements exhausted");
/* no more unhandled elements, we are done */
return GST_ITERATOR_DONE;
}
} else {
/* everything added to the queue got reffed */
*result = g_queue_pop_head (bit->queue);
}
GST_DEBUG_OBJECT (bin, "queue head gives %s", GST_ELEMENT_NAME (*result));
/* update degrees of linked elements */
update_degree (GST_ELEMENT_CAST (*result), bit);
return GST_ITERATOR_OK;
}
/* clear queues, recalculate the degrees and restart. */
static void
gst_bin_sort_iterator_resync (GstBinSortIterator * bit)
{
GstBin *bin = bit->bin;
GST_DEBUG_OBJECT (bin, "resync");
bit->dirty = FALSE;
clear_queue (bit->queue);
/* reset degrees */
g_list_foreach (bin->children, (GFunc) reset_degree, bit);
/* calc degrees, incrementing */
bit->mode = 1;
g_list_foreach (bin->children, (GFunc) update_degree, bit);
/* for the rest of the function we decrement the degrees */
bit->mode = -1;
}
/* clear queues, unref bin and free iterator. */
static void
gst_bin_sort_iterator_free (GstBinSortIterator * bit)
{
GstBin *bin = bit->bin;
GST_DEBUG_OBJECT (bin, "free");
clear_queue (bit->queue);
g_queue_free (bit->queue);
g_hash_table_destroy (bit->hash);
gst_object_unref (bin);
g_free (bit);
}
/* should be called with the bin LOCK held */
static GstIterator *
gst_bin_sort_iterator_new (GstBin * bin)
{
GstBinSortIterator *result;
/* we don't need an ItemFunction because we ref the items in the _next
* method already */
result = (GstBinSortIterator *)
gst_iterator_new (sizeof (GstBinSortIterator),
GST_TYPE_ELEMENT,
GST_OBJECT_GET_LOCK (bin),
&bin->priv->structure_cookie,
(GstIteratorNextFunction) gst_bin_sort_iterator_next,
(GstIteratorItemFunction) NULL,
(GstIteratorResyncFunction) gst_bin_sort_iterator_resync,
(GstIteratorFreeFunction) gst_bin_sort_iterator_free);
result->queue = g_queue_new ();
result->hash = g_hash_table_new (NULL, NULL);
gst_object_ref (bin);
result->bin = bin;
gst_bin_sort_iterator_resync (result);
return (GstIterator *) result;
}
/**
* gst_bin_iterate_sorted:
* @bin: a #GstBin
*
* Gets an iterator for the elements in this bin in topologically
* sorted order. This means that the elements are returned from
* the most downstream elements (sinks) to the sources.
*
* This function is used internally to perform the state changes
* of the bin elements and for clock selection.
*
* Each element yielded by the iterator will have its refcount increased, so
* unref after use.
*
* MT safe. Caller owns returned value.
*
* Returns: a #GstIterator of #GstElement, or NULL
*/
GstIterator *
gst_bin_iterate_sorted (GstBin * bin)
{
GstIterator *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
GST_OBJECT_LOCK (bin);
result = gst_bin_sort_iterator_new (bin);
GST_OBJECT_UNLOCK (bin);
return result;
}
static GstStateChangeReturn
gst_bin_element_set_state (GstBin * bin, GstElement * element,
GstClockTime base_time, GstClockTime start_time, GstState current,
GstState next)
{
GstStateChangeReturn ret;
GstState pending, child_current, child_pending;
gboolean locked;
GList *found;
GST_STATE_LOCK (element);
GST_OBJECT_LOCK (element);
/* set base_time and start time on child */
GST_ELEMENT_START_TIME (element) = start_time;
element->base_time = base_time;
/* peel off the locked flag */
locked = GST_OBJECT_FLAG_IS_SET (element, GST_ELEMENT_LOCKED_STATE);
/* Get the previous set_state result to preserve NO_PREROLL and ASYNC */
ret = GST_STATE_RETURN (element);
child_current = GST_STATE (element);
child_pending = GST_STATE_PENDING (element);
GST_OBJECT_UNLOCK (element);
/* skip locked elements */
if (G_UNLIKELY (locked))
goto locked;
/* if the element was no preroll, just start changing the state regardless
* if it had async elements (in the case of a bin) because they won't preroll
* anyway. */
if (G_UNLIKELY (ret == GST_STATE_CHANGE_NO_PREROLL)) {
GST_DEBUG_OBJECT (element, "element is NO_PREROLL, ignore async elements");
goto no_preroll;
}
GST_OBJECT_LOCK (bin);
pending = GST_STATE_PENDING (bin);
/* Try not to change the state of elements that are already in the state we're
* going to */
if (!(next == GST_STATE_PLAYING || child_pending != GST_STATE_VOID_PENDING ||
(child_pending == GST_STATE_VOID_PENDING &&
((pending > child_current && next > child_current) ||
(pending < child_current && next < child_current)))))
goto unneeded;
/* the element was busy with an upwards async state change, we must wait for
* an ASYNC_DONE message before we attemp to change the state. */
if ((found =
find_message (bin, GST_OBJECT_CAST (element),
GST_MESSAGE_ASYNC_START))) {
#ifndef GST_DISABLE_GST_DEBUG
GstMessage *message = GST_MESSAGE_CAST (found->data);
GST_DEBUG_OBJECT (element, "element message %p, %s async busy",
message, GST_ELEMENT_NAME (GST_MESSAGE_SRC (message)));
#endif
/* only wait for upward state changes */
if (next > current) {
/* We found an async element check if we can force its state to change or
* if we have to wait for it to preroll. */
if (G_UNLIKELY (!enable_latency)) {
g_warning ("Future versions of GStreamer will wait for element \"%s\"\n"
"\tto preroll in order to perform correct latency calculations.\n"
"\tPlease verify that the application continues to work correctly by\n"
"\tsetting the environment variable GST_COMPAT to a value containing\n"
"\tthe string 'live-preroll'.", GST_ELEMENT_NAME (element));
goto no_latency;
}
goto was_busy;
}
}
no_latency:
GST_OBJECT_UNLOCK (bin);
no_preroll:
GST_DEBUG_OBJECT (bin,
"setting element %s to %s, base_time %" GST_TIME_FORMAT,
GST_ELEMENT_NAME (element), gst_element_state_get_name (next),
GST_TIME_ARGS (base_time));
/* change state */
ret = gst_element_set_state (element, next);
GST_STATE_UNLOCK (element);
return ret;
locked:
{
GST_DEBUG_OBJECT (element,
"element is locked, return previous return %s",
gst_element_state_change_return_get_name (ret));
GST_STATE_UNLOCK (element);
return ret;
}
was_busy:
{
GST_DEBUG_OBJECT (element, "element was busy, delaying state change");
GST_OBJECT_UNLOCK (bin);
GST_STATE_UNLOCK (element);
return GST_STATE_CHANGE_ASYNC;
}
unneeded:
{
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
"skipping transition from %s to %s, since bin pending"
" is %s : last change state return follows",
gst_element_state_get_name (child_current),
gst_element_state_get_name (next),
gst_element_state_get_name (pending));
GST_OBJECT_UNLOCK (bin);
GST_STATE_UNLOCK (element);
return ret;
}
}
/* gst_iterator_fold functions for pads_activate
* Note how we don't stop the iterator when we fail an activation. This is
* probably a FIXME since when one pad activation fails, we don't want to
* continue our state change. */
static gboolean
activate_pads (GstPad * pad, GValue * ret, gboolean * active)
{
if (!gst_pad_set_active (pad, *active))
g_value_set_boolean (ret, FALSE);
else if (!*active)
gst_pad_set_caps (pad, NULL);
/* unref the object that was reffed for us by _fold */
gst_object_unref (pad);
return TRUE;
}
/* returns false on error or early cutout (will never happen because the fold
* function always returns TRUE, see FIXME above) of the fold, true if all
* pads in @iter were (de)activated successfully. */
static gboolean
iterator_activate_fold_with_resync (GstIterator * iter, gpointer user_data)
{
GstIteratorResult ires;
GValue ret = { 0 };
/* no need to unset this later, it's just a boolean */
g_value_init (&ret, G_TYPE_BOOLEAN);
g_value_set_boolean (&ret, TRUE);
while (1) {
ires = gst_iterator_fold (iter, (GstIteratorFoldFunction) activate_pads,
&ret, user_data);
switch (ires) {
case GST_ITERATOR_RESYNC:
/* need to reset the result again */
g_value_set_boolean (&ret, TRUE);
gst_iterator_resync (iter);
break;
case GST_ITERATOR_DONE:
/* all pads iterated, return collected value */
goto done;
default:
/* iterator returned _ERROR or premature end with _OK,
* mark an error and exit */
g_value_set_boolean (&ret, FALSE);
goto done;
}
}
done:
/* return collected value */
return g_value_get_boolean (&ret);
}
/* is called with STATE_LOCK
*/
static gboolean
gst_bin_src_pads_activate (GstBin * bin, gboolean active)
{
GstIterator *iter;
gboolean fold_ok;
GST_DEBUG_OBJECT (bin, "src_pads_activate with active %d", active);
iter = gst_element_iterate_src_pads ((GstElement *) bin);
fold_ok = iterator_activate_fold_with_resync (iter, &active);
gst_iterator_free (iter);
if (G_UNLIKELY (!fold_ok))
goto failed;
GST_DEBUG_OBJECT (bin, "pads_activate successful");
return TRUE;
/* ERRORS */
failed:
{
GST_DEBUG_OBJECT (bin, "source pads_activate failed");
return FALSE;
}
}
/**
* gst_bin_recalculate_latency:
* @bin: a #GstBin
*
* Query @bin for the current latency using and reconfigures this latency to all the
* elements with a LATENCY event.
*
* This method is typically called on the pipeline when a #GST_MESSAGE_LATENCY
* is posted on the bus.
*
* This function simply emits the 'do-latency' signal so any custom latency
* calculations will be performed.
*
* Returns: %TRUE if the latency could be queried and reconfigured.
*
* Since: 0.10.22.
*/
gboolean
gst_bin_recalculate_latency (GstBin * bin)
{
gboolean res;
g_signal_emit (bin, gst_bin_signals[DO_LATENCY], 0, &res);
GST_DEBUG_OBJECT (bin, "latency returned %d", res);
return res;
}
static gboolean
gst_bin_do_latency_func (GstBin * bin)
{
GstQuery *query;
GstElement *element;
GstClockTime min_latency, max_latency;
gboolean res;
g_return_val_if_fail (GST_IS_BIN (bin), FALSE);
element = GST_ELEMENT_CAST (bin);
GST_DEBUG_OBJECT (element, "querying latency");
query = gst_query_new_latency ();
if ((res = gst_element_query (element, query))) {
gboolean live;
gst_query_parse_latency (query, &live, &min_latency, &max_latency);
GST_DEBUG_OBJECT (element,
"got min latency %" GST_TIME_FORMAT ", max latency %"
GST_TIME_FORMAT ", live %d", GST_TIME_ARGS (min_latency),
GST_TIME_ARGS (max_latency), live);
if (max_latency < min_latency) {
/* this is an impossible situation, some parts of the pipeline might not
* work correctly. We post a warning for now. */
GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
("Impossible to configure latency: max %" GST_TIME_FORMAT " < min %"
GST_TIME_FORMAT ". Add queues or other buffering elements.",
GST_TIME_ARGS (max_latency), GST_TIME_ARGS (min_latency)));
}
/* configure latency on elements */
res = gst_element_send_event (element, gst_event_new_latency (min_latency));
if (res) {
GST_INFO_OBJECT (element, "configured latency of %" GST_TIME_FORMAT,
GST_TIME_ARGS (min_latency));
} else {
GST_WARNING_OBJECT (element,
"failed to configure latency of %" GST_TIME_FORMAT,
GST_TIME_ARGS (min_latency));
GST_ELEMENT_WARNING (element, CORE, CLOCK, (NULL),
("Failed to configure latency of %" GST_TIME_FORMAT,
GST_TIME_ARGS (min_latency)));
}
} else {
/* this is not a real problem, we just don't configure any latency. */
GST_WARNING_OBJECT (element, "failed to query latency");
}
gst_query_unref (query);
return res;
}
static GstStateChangeReturn
gst_bin_change_state_func (GstElement * element, GstStateChange transition)
{
GstBin *bin;
GstStateChangeReturn ret;
GstState current, next;
gboolean have_async;
gboolean have_no_preroll;
GstClockTime base_time, start_time;
GstIterator *it;
gboolean done;
/* we don't need to take the STATE_LOCK, it is already taken */
current = (GstState) GST_STATE_TRANSITION_CURRENT (transition);
next = (GstState) GST_STATE_TRANSITION_NEXT (transition);
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
"changing state of children from %s to %s",
gst_element_state_get_name (current), gst_element_state_get_name (next));
bin = GST_BIN_CAST (element);
switch (next) {
case GST_STATE_PLAYING:
{
gboolean toplevel;
GST_OBJECT_LOCK (bin);
toplevel = BIN_IS_TOPLEVEL (bin);
GST_OBJECT_UNLOCK (bin);
if (toplevel)
gst_bin_recalculate_latency (bin);
break;
}
case GST_STATE_PAUSED:
/* Clear EOS list on next PAUSED */
GST_OBJECT_LOCK (bin);
GST_DEBUG_OBJECT (element, "clearing EOS elements");
bin_remove_messages (bin, NULL, GST_MESSAGE_EOS);
GST_OBJECT_UNLOCK (bin);
if (current == GST_STATE_READY)
if (!(gst_bin_src_pads_activate (bin, TRUE)))
goto activate_failure;
break;
case GST_STATE_READY:
/* Clear message list on next READY */
GST_OBJECT_LOCK (bin);
GST_DEBUG_OBJECT (element, "clearing all cached messages");
bin_remove_messages (bin, NULL, GST_MESSAGE_ANY);
GST_OBJECT_UNLOCK (bin);
if (current == GST_STATE_PAUSED)
if (!(gst_bin_src_pads_activate (bin, FALSE)))
goto activate_failure;
break;
case GST_STATE_NULL:
if (current == GST_STATE_READY)
if (!(gst_bin_src_pads_activate (bin, FALSE)))
goto activate_failure;
break;
default:
break;
}
/* this flag is used to make the async state changes return immediatly. We
* don't want them to interfere with this state change */
GST_OBJECT_LOCK (bin);
bin->polling = TRUE;
GST_OBJECT_UNLOCK (bin);
/* iterate in state change order */
it = gst_bin_iterate_sorted (bin);
/* mark if we've seen an ASYNC element in the bin when we did a state change.
* Note how we don't reset this value when a resync happens, the reason being
* that the async element posted ASYNC_START and we want to post ASYNC_DONE
* even after a resync when the async element is gone */
have_async = FALSE;
restart:
/* take base_time */
base_time = gst_element_get_base_time (element);
start_time = gst_element_get_start_time (element);
have_no_preroll = FALSE;
done = FALSE;
while (!done) {
gpointer data;
switch (gst_iterator_next (it, &data)) {
case GST_ITERATOR_OK:
{
GstElement *child;
child = GST_ELEMENT_CAST (data);
/* set state and base_time now */
ret = gst_bin_element_set_state (bin, child, base_time, start_time,
current, next);
switch (ret) {
case GST_STATE_CHANGE_SUCCESS:
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
"child '%s' changed state to %d(%s) successfully",
GST_ELEMENT_NAME (child), next,
gst_element_state_get_name (next));
break;
case GST_STATE_CHANGE_ASYNC:
{
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
"child '%s' is changing state asynchronously to %s",
GST_ELEMENT_NAME (child), gst_element_state_get_name (next));
have_async = TRUE;
break;
}
case GST_STATE_CHANGE_FAILURE:{
GstObject *parent;
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
"child '%s' failed to go to state %d(%s)",
GST_ELEMENT_NAME (child),
next, gst_element_state_get_name (next));
/* Only fail if the child is still inside
* this bin. It might've been removed already
* because of the error by the bin subclass
* to ignore the error. */
parent = gst_object_get_parent (GST_OBJECT_CAST (child));
if (parent == GST_OBJECT_CAST (element)) {
/* element is still in bin, really error now */
gst_object_unref (child);
gst_object_unref (parent);
goto done;
}
/* child removed from bin, let the resync code redo the state
* change */
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
"child '%s' was removed from the bin",
GST_ELEMENT_NAME (child));
if (parent)
gst_object_unref (parent);
break;
}
case GST_STATE_CHANGE_NO_PREROLL:
GST_CAT_INFO_OBJECT (GST_CAT_STATES, element,
"child '%s' changed state to %d(%s) successfully without preroll",
GST_ELEMENT_NAME (child), next,
gst_element_state_get_name (next));
have_no_preroll = TRUE;
break;
default:
g_assert_not_reached ();
break;
}
gst_object_unref (child);
break;
}
case GST_ITERATOR_RESYNC:
GST_CAT_DEBUG (GST_CAT_STATES, "iterator doing resync");
gst_iterator_resync (it);
goto restart;
default:
case GST_ITERATOR_DONE:
GST_CAT_DEBUG (GST_CAT_STATES, "iterator done");
done = TRUE;
break;
}
}
ret = parent_class->change_state (element, transition);
if (G_UNLIKELY (ret == GST_STATE_CHANGE_FAILURE))
goto done;
if (have_no_preroll) {
GST_CAT_DEBUG (GST_CAT_STATES,
"we have NO_PREROLL elements %s -> NO_PREROLL",
gst_element_state_change_return_get_name (ret));
ret = GST_STATE_CHANGE_NO_PREROLL;
} else if (have_async) {
GST_CAT_DEBUG (GST_CAT_STATES, "we have ASYNC elements %s -> ASYNC",
gst_element_state_change_return_get_name (ret));
ret = GST_STATE_CHANGE_ASYNC;
}
done:
gst_iterator_free (it);
GST_OBJECT_LOCK (bin);
bin->polling = FALSE;
/* it's possible that we did not get ASYNC from the children while the bin is
* simulating ASYNC behaviour by posting an ASYNC_DONE message on the bus with
* itself as the source. In that case we still want to check if the state
* change completed. */
if (ret != GST_STATE_CHANGE_ASYNC && !bin->priv->pending_async_done) {
/* no element returned ASYNC and there are no pending async_done messages,
* we can just complete. */
GST_DEBUG_OBJECT (bin, "no async elements");
goto state_end;
}
/* when we get here an ASYNC element was found */
if (GST_STATE_TARGET (bin) <= GST_STATE_READY) {
/* we ignore ASYNC state changes when we go to READY or NULL */
GST_DEBUG_OBJECT (bin, "target state %s <= READY",
gst_element_state_get_name (GST_STATE_TARGET (bin)));
goto state_end;
}
GST_DEBUG_OBJECT (bin, "check async elements");
/* check if all elements managed to commit their state already */
if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
/* nothing found, remove all old ASYNC_DONE messages. This can happen when
* all the elements commited their state while we were doing the state
* change. We will still return ASYNC for consistency but we commit the
* state already so that a _get_state() will return immediatly. */
bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
GST_DEBUG_OBJECT (bin, "async elements commited");
bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, FALSE);
}
state_end:
bin->priv->pending_async_done = FALSE;
GST_OBJECT_UNLOCK (bin);
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, element,
"done changing bin's state from %s to %s, now in %s, ret %s",
gst_element_state_get_name (current),
gst_element_state_get_name (next),
gst_element_state_get_name (GST_STATE (element)),
gst_element_state_change_return_get_name (ret));
return ret;
/* ERRORS */
activate_failure:
{
GST_CAT_WARNING_OBJECT (GST_CAT_STATES, element,
"failure (de)activating src pads");
return GST_STATE_CHANGE_FAILURE;
}
}
/*
* This function is a utility event handler for seek events.
* It will send the event to all sinks or sources depending on the
* event-direction.
*
* Applications are free to override this behaviour and
* implement their own seek handler, but this will work for
* pretty much all cases in practice.
*/
static gboolean
gst_bin_send_event (GstElement * element, GstEvent * event)
{
GstBin *bin = GST_BIN_CAST (element);
GstIterator *iter;
gboolean res = TRUE;
gboolean done = FALSE;
if (GST_EVENT_IS_DOWNSTREAM (event)) {
iter = gst_bin_iterate_sources (bin);
GST_DEBUG_OBJECT (bin, "Sending %s event to src children",
GST_EVENT_TYPE_NAME (event));
} else {
iter = gst_bin_iterate_sinks (bin);
GST_DEBUG_OBJECT (bin, "Sending %s event to sink children",
GST_EVENT_TYPE_NAME (event));
}
while (!done) {
gpointer data;
switch (gst_iterator_next (iter, &data)) {
case GST_ITERATOR_OK:
{
GstElement *child;
gst_event_ref (event);
child = GST_ELEMENT_CAST (data);
res &= gst_element_send_event (child, event);
gst_object_unref (child);
break;
}
case GST_ITERATOR_RESYNC:
gst_iterator_resync (iter);
res = TRUE;
break;
case GST_ITERATOR_DONE:
done = TRUE;
break;
case GST_ITERATOR_ERROR:
g_assert_not_reached ();
break;
}
}
gst_iterator_free (iter);
gst_event_unref (event);
return res;
}
/* this is the function called by the threadpool. When async elements commit
* their state, this function will attempt to bring the bin to the next state.
*/
static void
gst_bin_continue_func (BinContinueData * data)
{
GstBin *bin;
GstState current, next, pending;
GstStateChange transition;
bin = data->bin;
pending = data->pending;
GST_DEBUG_OBJECT (bin, "waiting for state lock");
GST_STATE_LOCK (bin);
GST_DEBUG_OBJECT (bin, "doing state continue");
GST_OBJECT_LOCK (bin);
/* if a new state change happened after this thread was scheduled, we return
* immediatly. */
if (data->cookie != GST_ELEMENT_CAST (bin)->state_cookie)
goto interrupted;
current = GST_STATE (bin);
next = GST_STATE_GET_NEXT (current, pending);
transition = (GstStateChange) GST_STATE_TRANSITION (current, next);
GST_STATE_NEXT (bin) = next;
GST_STATE_PENDING (bin) = pending;
/* mark busy */
GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
GST_OBJECT_UNLOCK (bin);
GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
"continue state change %s to %s, final %s",
gst_element_state_get_name (current),
gst_element_state_get_name (next), gst_element_state_get_name (pending));
gst_element_change_state (GST_ELEMENT_CAST (bin), transition);
GST_STATE_UNLOCK (bin);
GST_DEBUG_OBJECT (bin, "state continue done");
gst_object_unref (bin);
g_slice_free (BinContinueData, data);
return;
interrupted:
{
GST_OBJECT_UNLOCK (bin);
GST_STATE_UNLOCK (bin);
GST_DEBUG_OBJECT (bin, "state continue aborted due to intervening change");
gst_object_unref (bin);
g_slice_free (BinContinueData, data);
return;
}
}
static GstBusSyncReply
bin_bus_handler (GstBus * bus, GstMessage * message, GstBin * bin)
{
GstBinClass *bclass;
bclass = GST_BIN_GET_CLASS (bin);
if (bclass->handle_message)
bclass->handle_message (bin, message);
else
gst_message_unref (message);
return GST_BUS_DROP;
}
static void
bin_push_state_continue (BinContinueData * data)
{
GstBinClass *klass;
GstBin *bin;
/* ref was taken */
bin = data->bin;
klass = GST_BIN_GET_CLASS (bin);
GST_DEBUG_OBJECT (bin, "pushing continue on thread pool");
g_thread_pool_push (klass->pool, data, NULL);
}
/* an element started an async state change, if we were not busy with a state
* change, we perform a lost state.
* This function is called with the OBJECT lock.
*/
static void
bin_handle_async_start (GstBin * bin, gboolean new_base_time)
{
GstState old_state, new_state;
gboolean toplevel;
GstMessage *amessage = NULL;
if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
goto had_error;
/* get our toplevel state */
toplevel = BIN_IS_TOPLEVEL (bin);
/* prepare an ASYNC_START message, we always post the start message even if we
* are busy with a state change or when we are NO_PREROLL. */
if (!toplevel)
/* non toplevel bin, prepare async-start for the parent */
amessage =
gst_message_new_async_start (GST_OBJECT_CAST (bin), new_base_time);
if (bin->polling || GST_STATE_PENDING (bin) != GST_STATE_VOID_PENDING)
goto was_busy;
/* async starts are ignored when we are NO_PREROLL */
if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_NO_PREROLL)
goto was_no_preroll;
old_state = GST_STATE (bin);
/* when we PLAYING we go back to PAUSED, when preroll happens, we go back to
* PLAYING after optionally redistributing the base_time. */
if (old_state > GST_STATE_PAUSED)
new_state = GST_STATE_PAUSED;
else
new_state = old_state;
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin,
"lost state of %s, new %s", gst_element_state_get_name (old_state),
gst_element_state_get_name (new_state));
GST_STATE (bin) = new_state;
GST_STATE_NEXT (bin) = new_state;
GST_STATE_PENDING (bin) = new_state;
GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
GST_OBJECT_UNLOCK (bin);
/* post message */
gst_element_post_message (GST_ELEMENT_CAST (bin),
gst_message_new_state_changed (GST_OBJECT_CAST (bin),
new_state, new_state, new_state));
post_start:
if (amessage) {
/* post our ASYNC_START. */
GST_DEBUG_OBJECT (bin, "posting ASYNC_START to parent");
gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
}
GST_OBJECT_LOCK (bin);
return;
had_error:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
return;
}
was_busy:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
GST_OBJECT_UNLOCK (bin);
goto post_start;
}
was_no_preroll:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "ignoring, we are NO_PREROLL");
GST_OBJECT_UNLOCK (bin);
goto post_start;
}
}
/* this function is called when there are no more async elements in the bin. We
* post a state changed message and an ASYNC_DONE message.
* This function is called with the OBJECT lock.
*/
static void
bin_handle_async_done (GstBin * bin, GstStateChangeReturn ret,
gboolean flag_pending)
{
GstState current, pending, target;
GstStateChangeReturn old_ret;
GstState old_state, old_next;
gboolean toplevel;
GstMessage *smessage = NULL, *amessage = NULL;
BinContinueData *cont = NULL;
if (GST_STATE_RETURN (bin) == GST_STATE_CHANGE_FAILURE)
goto had_error;
pending = GST_STATE_PENDING (bin);
if (bin->polling)
goto was_busy;
/* check if there is something to commit */
if (pending == GST_STATE_VOID_PENDING)
goto nothing_pending;
old_ret = GST_STATE_RETURN (bin);
GST_STATE_RETURN (bin) = ret;
/* move to the next target state */
target = GST_STATE_TARGET (bin);
pending = GST_STATE_PENDING (bin) = target;
amessage = gst_message_new_async_done (GST_OBJECT_CAST (bin));
old_state = GST_STATE (bin);
/* this is the state we should go to next */
old_next = GST_STATE_NEXT (bin);
if (old_next != GST_STATE_PLAYING) {
GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
"committing state from %s to %s, old pending %s",
gst_element_state_get_name (old_state),
gst_element_state_get_name (old_next),
gst_element_state_get_name (pending));
/* update current state */
current = GST_STATE (bin) = old_next;
} else {
GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
"setting state from %s to %s, pending %s",
gst_element_state_get_name (old_state),
gst_element_state_get_name (old_state),
gst_element_state_get_name (pending));
current = old_state;
}
/* get our toplevel state */
toplevel = BIN_IS_TOPLEVEL (bin);
/* see if we reached the final state. If we are not toplevel, we also have to
* stop here, the parent will continue our state. */
if ((pending == current) || !toplevel) {
GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
"completed state change, pending VOID");
/* mark VOID pending */
pending = GST_STATE_VOID_PENDING;
GST_STATE_PENDING (bin) = pending;
GST_STATE_NEXT (bin) = GST_STATE_VOID_PENDING;
} else {
GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin,
"continue state change, pending %s",
gst_element_state_get_name (pending));
cont = g_slice_new (BinContinueData);
/* ref to the bin */
cont->bin = gst_object_ref (bin);
/* cookie to detect concurrent state change */
cont->cookie = GST_ELEMENT_CAST (bin)->state_cookie;
/* pending target state */
cont->pending = pending;
/* mark busy */
GST_STATE_RETURN (bin) = GST_STATE_CHANGE_ASYNC;
GST_STATE_NEXT (bin) = GST_STATE_GET_NEXT (old_state, pending);
}
if (old_next != GST_STATE_PLAYING) {
if (old_state != old_next || old_ret == GST_STATE_CHANGE_ASYNC) {
smessage = gst_message_new_state_changed (GST_OBJECT_CAST (bin),
old_state, old_next, pending);
}
}
GST_OBJECT_UNLOCK (bin);
if (smessage) {
GST_DEBUG_OBJECT (bin, "posting state change message");
gst_element_post_message (GST_ELEMENT_CAST (bin), smessage);
}
if (amessage) {
/* post our combined ASYNC_DONE when all is ASYNC_DONE. */
GST_DEBUG_OBJECT (bin, "posting ASYNC_DONE to parent");
gst_element_post_message (GST_ELEMENT_CAST (bin), amessage);
}
GST_OBJECT_LOCK (bin);
if (cont) {
/* toplevel, start continue state */
GST_DEBUG_OBJECT (bin, "all async-done, starting state continue");
bin_push_state_continue (cont);
} else {
GST_DEBUG_OBJECT (bin, "state change complete");
GST_STATE_BROADCAST (bin);
}
return;
had_error:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "we had an error");
return;
}
was_busy:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_STATES, bin, "state change busy");
/* if we were busy with a state change and we are requested to flag a
* pending async done, we do so here */
if (flag_pending)
bin->priv->pending_async_done = TRUE;
return;
}
nothing_pending:
{
GST_CAT_INFO_OBJECT (GST_CAT_STATES, bin, "nothing pending");
return;
}
}
/* handle child messages:
*
* This method is called synchronously when a child posts a message on
* the internal bus.
*
* GST_MESSAGE_EOS: This message is only posted by sinks
* in the PLAYING state. If all sinks posted the EOS message, post
* one upwards.
*
* GST_MESSAGE_STATE_DIRTY: Deprecated
*
* GST_MESSAGE_SEGMENT_START: just collect, never forward upwards. If an
* element posts segment_start twice, only the last message is kept.
*
* GST_MESSAGE_SEGMENT_DONE: replace SEGMENT_START message from same poster
* with the segment_done message. If there are no more segment_start
* messages, post segment_done message upwards.
*
* GST_MESSAGE_DURATION: remove all previously cached duration messages.
* Whenever someone performs a duration query on the bin, we store the
* result so we can answer it quicker the next time. Any element that
* changes its duration marks our cached values invalid.
* This message is also posted upwards. This is currently disabled
* because too many elements don't post DURATION messages when the
* duration changes.
*
* GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it
* can no longer provide a clock. The default bin behaviour is to
* check if the lost clock was the one provided by the bin. If so and
* we are currently in the PLAYING state, we forward the message to
* our parent.
* This message is also generated when we remove a clock provider from
* a bin. If this message is received by the application, it should
* PAUSE the pipeline and set it back to PLAYING to force a new clock
* and a new base_time distribution.
*
* GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element
* can provide a clock. This mostly happens when we add a new clock
* provider to the bin. The default behaviour of the bin is to mark the
* currently selected clock as dirty, which will perform a clock
* recalculation the next time we are asked to provide a clock.
* This message is never sent to the application but is forwarded to
* the parent.
*
* GST_MESSAGE_ASYNC_START: Create an internal ELEMENT message that stores
* the state of the element and the fact that the element will need a
* new base_time. This message is not forwarded to the application.
*
* GST_MESSAGE_ASYNC_DONE: Find the internal ELEMENT message we kept for the
* element when it posted ASYNC_START. If all elements are done, post a
* ASYNC_DONE message to the parent.
*
* OTHER: post upwards.
*/
static void
gst_bin_handle_message_func (GstBin * bin, GstMessage * message)
{
GstObject *src;
GstMessageType type;
GstMessage *tmessage;
guint32 seqnum;
src = GST_MESSAGE_SRC (message);
type = GST_MESSAGE_TYPE (message);
GST_DEBUG_OBJECT (bin, "[msg %p] handling child %s message of type %s",
message, src ? GST_ELEMENT_NAME (src) : "(NULL)",
GST_MESSAGE_TYPE_NAME (message));
switch (type) {
case GST_MESSAGE_ERROR:
{
GST_OBJECT_LOCK (bin);
/* flag error */
GST_DEBUG_OBJECT (bin, "got ERROR message, unlocking state change");
GST_STATE_RETURN (bin) = GST_STATE_CHANGE_FAILURE;
GST_STATE_BROADCAST (bin);
GST_OBJECT_UNLOCK (bin);
goto forward;
}
case GST_MESSAGE_EOS:
{
gboolean eos;
/* collect all eos messages from the children */
GST_OBJECT_LOCK (bin);
/* ref message for future use */
gst_message_ref (message);
bin_replace_message (bin, message, GST_MESSAGE_EOS);
eos = is_eos (bin);
GST_OBJECT_UNLOCK (bin);
/* if we are completely EOS, we forward an EOS message */
if (eos) {
seqnum = gst_message_get_seqnum (message);
tmessage = gst_message_new_eos (GST_OBJECT_CAST (bin));
gst_message_set_seqnum (tmessage, seqnum);
GST_DEBUG_OBJECT (bin,
"all sinks posted EOS, posting seqnum #%" G_GUINT32_FORMAT, seqnum);
gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
}
gst_message_unref (message);
break;
}
case GST_MESSAGE_STATE_DIRTY:
{
GST_WARNING_OBJECT (bin, "received deprecated STATE_DIRTY message");
/* free message */
gst_message_unref (message);
break;
}
case GST_MESSAGE_SEGMENT_START:{
gboolean post = FALSE;
GstFormat format;
gint64 position;
gst_message_parse_segment_start (message, &format, &position);
seqnum = gst_message_get_seqnum (message);
GST_OBJECT_LOCK (bin);
/* if this is the first segment-start, post to parent but not to the
* application */
if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START) &&
(GST_OBJECT_PARENT (bin) != NULL)) {
post = TRUE;
}
/* replace any previous segment_start message from this source
* with the new segment start message */
bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
GST_OBJECT_UNLOCK (bin);
if (post) {
tmessage = gst_message_new_segment_start (GST_OBJECT_CAST (bin),
format, position);
gst_message_set_seqnum (tmessage, seqnum);
/* post segment start with initial format and position. */
GST_DEBUG_OBJECT (bin, "posting SEGMENT_START (%u) bus message: %p",
seqnum, message);
gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
}
break;
}
case GST_MESSAGE_SEGMENT_DONE:
{
gboolean post = FALSE;
GstFormat format;
gint64 position;
gst_message_parse_segment_done (message, &format, &position);
seqnum = gst_message_get_seqnum (message);
GST_OBJECT_LOCK (bin);
bin_replace_message (bin, message, GST_MESSAGE_SEGMENT_START);
/* if there are no more segment_start messages, everybody posted
* a segment_done and we can post one on the bus. */
/* we don't care who still has a pending segment start */
if (!find_message (bin, NULL, GST_MESSAGE_SEGMENT_START)) {
/* nothing found */
post = TRUE;
/* remove all old segment_done messages */
bin_remove_messages (bin, NULL, GST_MESSAGE_SEGMENT_DONE);
}
GST_OBJECT_UNLOCK (bin);
if (post) {
tmessage = gst_message_new_segment_done (GST_OBJECT_CAST (bin),
format, position);
gst_message_set_seqnum (tmessage, seqnum);
/* post segment done with latest format and position. */
GST_DEBUG_OBJECT (bin, "posting SEGMENT_DONE (%u) bus message: %p",
seqnum, message);
gst_element_post_message (GST_ELEMENT_CAST (bin), tmessage);
}
break;
}
case GST_MESSAGE_DURATION:
{
/* remove all cached duration messages, next time somebody asks
* for duration, we will recalculate. */
GST_OBJECT_LOCK (bin);
bin_remove_messages (bin, NULL, GST_MESSAGE_DURATION);
GST_OBJECT_UNLOCK (bin);
goto forward;
}
case GST_MESSAGE_CLOCK_LOST:
{
GstClock **provided_clock_p;
GstElement **clock_provider_p;
gboolean playing, provided, forward;
GstClock *clock;
gst_message_parse_clock_lost (message, &clock);
GST_OBJECT_LOCK (bin);
bin->clock_dirty = TRUE;
/* if we lost the clock that we provided, post to parent but
* only if we are PLAYING. */
provided = (clock == bin->provided_clock);
playing = (GST_STATE (bin) == GST_STATE_PLAYING);
forward = playing & provided;
if (provided) {
GST_DEBUG_OBJECT (bin,
"Lost clock %" GST_PTR_FORMAT " provided by %" GST_PTR_FORMAT,
bin->provided_clock, bin->clock_provider);
provided_clock_p = &bin->provided_clock;
clock_provider_p = &bin->clock_provider;
gst_object_replace ((GstObject **) provided_clock_p, NULL);
gst_object_replace ((GstObject **) clock_provider_p, NULL);
}
GST_DEBUG_OBJECT (bin, "provided %d, playing %d, forward %d",
provided, playing, forward);
GST_OBJECT_UNLOCK (bin);
if (forward)
goto forward;
/* free message */
gst_message_unref (message);
break;
}
case GST_MESSAGE_CLOCK_PROVIDE:
{
gboolean forward;
GST_OBJECT_LOCK (bin);
bin->clock_dirty = TRUE;
/* a new clock is available, post to parent but not
* to the application */
forward = GST_OBJECT_PARENT (bin) != NULL;
GST_OBJECT_UNLOCK (bin);
if (forward)
goto forward;
/* free message */
gst_message_unref (message);
break;
}
case GST_MESSAGE_ASYNC_START:
{
gboolean new_base_time;
GstState target;
GST_DEBUG_OBJECT (bin, "ASYNC_START message %p, %s", message,
src ? GST_OBJECT_NAME (src) : "(NULL)");
gst_message_parse_async_start (message, &new_base_time);
GST_OBJECT_LOCK (bin);
/* we ignore the message if we are going to <= READY */
target = GST_STATE_TARGET (bin);
if (target <= GST_STATE_READY)
goto ignore_start_message;
/* takes ownership of the message */
bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
bin_handle_async_start (bin, new_base_time);
GST_OBJECT_UNLOCK (bin);
break;
ignore_start_message:
{
GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
gst_element_state_get_name (target));
GST_OBJECT_UNLOCK (bin);
gst_message_unref (message);
break;
}
}
case GST_MESSAGE_ASYNC_DONE:
{
GstState target;
GST_DEBUG_OBJECT (bin, "ASYNC_DONE message %p, %s", message,
src ? GST_OBJECT_NAME (src) : "(NULL)");
GST_OBJECT_LOCK (bin);
target = GST_STATE_TARGET (bin);
/* ignore messages if we are shutting down */
if (target <= GST_STATE_READY)
goto ignore_done_message;
bin_replace_message (bin, message, GST_MESSAGE_ASYNC_START);
/* if there are no more ASYNC_START messages, everybody posted
* a ASYNC_DONE and we can post one on the bus. When checking, we
* don't care who still has a pending ASYNC_START */
if (!find_message (bin, NULL, GST_MESSAGE_ASYNC_START)) {
/* nothing found, remove all old ASYNC_DONE messages */
bin_remove_messages (bin, NULL, GST_MESSAGE_ASYNC_DONE);
GST_DEBUG_OBJECT (bin, "async elements commited");
/* when we get an async done message when a state change was busy, we
* need to set the pending_done flag so that at the end of the state
* change we can see if we need to verify pending async elements, hence
* the TRUE argument here. */
bin_handle_async_done (bin, GST_STATE_CHANGE_SUCCESS, TRUE);
} else {
GST_DEBUG_OBJECT (bin, "there are more async elements pending");
}
GST_OBJECT_UNLOCK (bin);
break;
ignore_done_message:
{
GST_DEBUG_OBJECT (bin, "ignoring message, target %s",
gst_element_state_get_name (target));
GST_OBJECT_UNLOCK (bin);
gst_message_unref (message);
break;
}
}
case GST_MESSAGE_STRUCTURE_CHANGE:
{
gboolean busy;
gst_message_parse_structure_change (message, NULL, NULL, &busy);
GST_OBJECT_LOCK (bin);
if (busy) {
/* while the pad is busy, avoid following it when doing state changes.
* Don't update the cookie yet, we will do that after the structure
* change finished and we are ready to inspect the new updated
* structure. */
bin_replace_message (bin, message, GST_MESSAGE_STRUCTURE_CHANGE);
message = NULL;
} else {
/* a pad link/unlink ended, signal the state change iterator that we
* need to resync by updating the structure_cookie. */
bin_remove_messages (bin, GST_MESSAGE_SRC (message),
GST_MESSAGE_STRUCTURE_CHANGE);
bin->priv->structure_cookie++;
}
GST_OBJECT_UNLOCK (bin);
if (message)
gst_message_unref (message);
break;
}
default:
goto forward;
}
return;
forward:
{
/* Send all other messages upward */
GST_DEBUG_OBJECT (bin, "posting message upward");
gst_element_post_message (GST_ELEMENT_CAST (bin), message);
return;
}
}
/* generic struct passed to all query fold methods */
typedef struct
{
GstQuery *query;
gint64 min;
gint64 max;
gboolean live;
} QueryFold;
typedef void (*QueryInitFunction) (GstBin * bin, QueryFold * fold);
typedef void (*QueryDoneFunction) (GstBin * bin, QueryFold * fold);
/* for duration/position we collect all durations/positions and take
* the MAX of all valid results */
static void
bin_query_min_max_init (GstBin * bin, QueryFold * fold)
{
fold->min = 0;
fold->max = -1;
fold->live = FALSE;
}
static gboolean
bin_query_duration_fold (GstElement * item, GValue * ret, QueryFold * fold)
{
if (gst_element_query (item, fold->query)) {
gint64 duration;
g_value_set_boolean (ret, TRUE);
gst_query_parse_duration (fold->query, NULL, &duration);
GST_DEBUG_OBJECT (item, "got duration %" G_GINT64_FORMAT, duration);
if (duration > fold->max)
fold->max = duration;
}
gst_object_unref (item);
return TRUE;
}
static void
bin_query_duration_done (GstBin * bin, QueryFold * fold)
{
GstFormat format;
gst_query_parse_duration (fold->query, &format, NULL);
/* store max in query result */
gst_query_set_duration (fold->query, format, fold->max);
GST_DEBUG_OBJECT (bin, "max duration %" G_GINT64_FORMAT, fold->max);
#ifdef DURATION_CACHING
/* and cache now */
GST_OBJECT_LOCK (bin);
bin->messages = g_list_prepend (bin->messages,
gst_message_new_duration (GST_OBJECT_CAST (bin), format, fold->max));
GST_OBJECT_UNLOCK (bin);
#endif
}
static gboolean
bin_query_position_fold (GstElement * item, GValue * ret, QueryFold * fold)
{
if (gst_element_query (item, fold->query)) {
gint64 position;
g_value_set_boolean (ret, TRUE);
gst_query_parse_position (fold->query, NULL, &position);
GST_DEBUG_OBJECT (item, "got position %" G_GINT64_FORMAT, position);
if (position > fold->max)
fold->max = position;
}
gst_object_unref (item);
return TRUE;
}
static void
bin_query_position_done (GstBin * bin, QueryFold * fold)
{
GstFormat format;
gst_query_parse_position (fold->query, &format, NULL);
/* store max in query result */
gst_query_set_position (fold->query, format, fold->max);
GST_DEBUG_OBJECT (bin, "max position %" G_GINT64_FORMAT, fold->max);
}
static gboolean
bin_query_latency_fold (GstElement * item, GValue * ret, QueryFold * fold)
{
if (gst_element_query (item, fold->query)) {
GstClockTime min, max;
gboolean live;
gst_query_parse_latency (fold->query, &live, &min, &max);
GST_DEBUG_OBJECT (item,
"got latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
", live %d", GST_TIME_ARGS (min), GST_TIME_ARGS (max), live);
/* for the combined latency we collect the MAX of all min latencies and
* the MIN of all max latencies */
if (live) {
if (min > fold->min)
fold->min = min;
if (fold->max == -1)
fold->max = max;
else if (max < fold->max)
fold->max = max;
if (fold->live == FALSE)
fold->live = live;
}
} else {
g_value_set_boolean (ret, FALSE);
GST_DEBUG_OBJECT (item, "failed query");
}
gst_object_unref (item);
return TRUE;
}
static void
bin_query_latency_done (GstBin * bin, QueryFold * fold)
{
/* store max in query result */
gst_query_set_latency (fold->query, fold->live, fold->min, fold->max);
GST_DEBUG_OBJECT (bin,
"latency min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT
", live %d", GST_TIME_ARGS (fold->min), GST_TIME_ARGS (fold->max),
fold->live);
}
/* generic fold, return first valid result */
static gboolean
bin_query_generic_fold (GstElement * item, GValue * ret, QueryFold * fold)
{
gboolean res;
if ((res = gst_element_query (item, fold->query))) {
g_value_set_boolean (ret, TRUE);
GST_DEBUG_OBJECT (item, "answered query %p", fold->query);
}
gst_object_unref (item);
/* and stop as soon as we have a valid result */
return !res;
}
static gboolean
gst_bin_query (GstElement * element, GstQuery * query)
{
GstBin *bin = GST_BIN_CAST (element);
GstIterator *iter;
gboolean res = FALSE;
GstIteratorFoldFunction fold_func;
QueryInitFunction fold_init = NULL;
QueryDoneFunction fold_done = NULL;
QueryFold fold_data;
GValue ret = { 0 };
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_DURATION:
{
#ifdef DURATION_CACHING
GList *cached;
GstFormat qformat;
gst_query_parse_duration (query, &qformat, NULL);
/* find cached duration query */
GST_OBJECT_LOCK (bin);
for (cached = bin->messages; cached; cached = g_list_next (cached)) {
GstMessage *message = (GstMessage *) cached->data;
if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION &&
GST_MESSAGE_SRC (message) == GST_OBJECT_CAST (bin)) {
GstFormat format;
gint64 duration;
gst_message_parse_duration (message, &format, &duration);
/* if cached same format, copy duration in query result */
if (format == qformat) {
GST_DEBUG_OBJECT (bin, "return cached duration %" G_GINT64_FORMAT,
duration);
GST_OBJECT_UNLOCK (bin);
gst_query_set_duration (query, qformat, duration);
res = TRUE;
goto exit;
}
}
}
GST_OBJECT_UNLOCK (bin);
#endif
/* no cached value found, iterate and collect durations */
fold_func = (GstIteratorFoldFunction) bin_query_duration_fold;
fold_init = bin_query_min_max_init;
fold_done = bin_query_duration_done;
break;
}
case GST_QUERY_POSITION:
{
fold_func = (GstIteratorFoldFunction) bin_query_position_fold;
fold_init = bin_query_min_max_init;
fold_done = bin_query_position_done;
break;
}
case GST_QUERY_LATENCY:
{
fold_func = (GstIteratorFoldFunction) bin_query_latency_fold;
fold_init = bin_query_min_max_init;
fold_done = bin_query_latency_done;
res = TRUE;
break;
}
default:
fold_func = (GstIteratorFoldFunction) bin_query_generic_fold;
break;
}
fold_data.query = query;
/* set the result of the query to FALSE initially */
g_value_init (&ret, G_TYPE_BOOLEAN);
g_value_set_boolean (&ret, res);
iter = gst_bin_iterate_sinks (bin);
GST_DEBUG_OBJECT (bin, "Sending query %p (type %s) to sink children",
query, GST_QUERY_TYPE_NAME (query));
if (fold_init)
fold_init (bin, &fold_data);
while (TRUE) {
GstIteratorResult ires;
ires = gst_iterator_fold (iter, fold_func, &ret, &fold_data);
switch (ires) {
case GST_ITERATOR_RESYNC:
gst_iterator_resync (iter);
if (fold_init)
fold_init (bin, &fold_data);
g_value_set_boolean (&ret, res);
break;
case GST_ITERATOR_OK:
case GST_ITERATOR_DONE:
res = g_value_get_boolean (&ret);
if (fold_done != NULL && res)
fold_done (bin, &fold_data);
goto done;
default:
res = FALSE;
goto done;
}
}
done:
gst_iterator_free (iter);
#ifdef DURATION_CACHING
exit:
#endif
GST_DEBUG_OBJECT (bin, "query %p result %d", query, res);
return res;
}
static gint
compare_name (GstElement * element, const gchar * name)
{
gint eq;
GST_OBJECT_LOCK (element);
eq = strcmp (GST_ELEMENT_NAME (element), name);
GST_OBJECT_UNLOCK (element);
if (eq != 0) {
gst_object_unref (element);
}
return eq;
}
/**
* gst_bin_get_by_name:
* @bin: a #GstBin
* @name: the element name to search for
*
* Gets the element with the given name from a bin. This
* function recurses into child bins.
*
* Returns NULL if no element with the given name is found in the bin.
*
* MT safe. Caller owns returned reference.
*
* Returns: the #GstElement with the given name, or NULL
*/
GstElement *
gst_bin_get_by_name (GstBin * bin, const gchar * name)
{
GstIterator *children;
gpointer result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
GST_CAT_INFO (GST_CAT_PARENTAGE, "[%s]: looking up child element %s",
GST_ELEMENT_NAME (bin), name);
children = gst_bin_iterate_recurse (bin);
result = gst_iterator_find_custom (children,
(GCompareFunc) compare_name, (gpointer) name);
gst_iterator_free (children);
return GST_ELEMENT_CAST (result);
}
/**
* gst_bin_get_by_name_recurse_up:
* @bin: a #GstBin
* @name: the element name to search for
*
* Gets the element with the given name from this bin. If the
* element is not found, a recursion is performed on the parent bin.
*
* Returns NULL if:
* - no element with the given name is found in the bin
*
* MT safe. Caller owns returned reference.
*
* Returns: the #GstElement with the given name, or NULL
*/
GstElement *
gst_bin_get_by_name_recurse_up (GstBin * bin, const gchar * name)
{
GstElement *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
g_return_val_if_fail (name != NULL, NULL);
result = gst_bin_get_by_name (bin, name);
if (!result) {
GstObject *parent;
parent = gst_object_get_parent (GST_OBJECT_CAST (bin));
if (parent) {
if (GST_IS_BIN (parent)) {
result = gst_bin_get_by_name_recurse_up (GST_BIN_CAST (parent), name);
}
gst_object_unref (parent);
}
}
return result;
}
static gint
compare_interface (GstElement * element, gpointer interface)
{
GType interface_type = (GType) interface;
gint ret;
if (G_TYPE_CHECK_INSTANCE_TYPE (element, interface_type)) {
ret = 0;
} else {
/* we did not find the element, need to release the ref
* added by the iterator */
gst_object_unref (element);
ret = 1;
}
return ret;
}
/**
* gst_bin_get_by_interface:
* @bin: a #GstBin
* @iface: the #GType of an interface
*
* Looks for an element inside the bin that implements the given
* interface. If such an element is found, it returns the element.
* You can cast this element to the given interface afterwards. If you want
* all elements that implement the interface, use
* gst_bin_iterate_all_by_interface(). This function recurses into child bins.
*
* MT safe. Caller owns returned reference.
*
* Returns: A #GstElement inside the bin implementing the interface
*/
GstElement *
gst_bin_get_by_interface (GstBin * bin, GType iface)
{
GstIterator *children;
gpointer result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
children = gst_bin_iterate_recurse (bin);
result = gst_iterator_find_custom (children, (GCompareFunc) compare_interface,
(gpointer) iface);
gst_iterator_free (children);
return GST_ELEMENT_CAST (result);
}
/**
* gst_bin_iterate_all_by_interface:
* @bin: a #GstBin
* @iface: the #GType of an interface
*
* Looks for all elements inside the bin that implements the given
* interface. You can safely cast all returned elements to the given interface.
* The function recurses inside child bins. The iterator will yield a series
* of #GstElement that should be unreffed after use.
*
* Each element yielded by the iterator will have its refcount increased, so
* unref after use.
*
* MT safe. Caller owns returned value.
*
* Returns: a #GstIterator of #GstElement for all elements in the bin
* implementing the given interface, or NULL
*/
GstIterator *
gst_bin_iterate_all_by_interface (GstBin * bin, GType iface)
{
GstIterator *children;
GstIterator *result;
g_return_val_if_fail (GST_IS_BIN (bin), NULL);
g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface), NULL);
children = gst_bin_iterate_recurse (bin);
result = gst_iterator_filter (children, (GCompareFunc) compare_interface,
(gpointer) iface);
return result;
}
#if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_REMOVE_DEPRECATED)
static xmlNodePtr
gst_bin_save_thyself (GstObject * object, xmlNodePtr parent)
{
GstBin *bin = GST_BIN_CAST (object);
xmlNodePtr childlist, elementnode;
GList *children;
GstElement *child;
if (GST_OBJECT_CLASS (parent_class)->save_thyself)
GST_OBJECT_CLASS (parent_class)->save_thyself (GST_OBJECT (bin), parent);
childlist = xmlNewChild (parent, NULL, (xmlChar *) "children", NULL);
GST_CAT_INFO (GST_CAT_XML, "[%s]: saving %d children",
GST_ELEMENT_NAME (bin), bin->numchildren);
children = g_list_last (bin->children);
while (children) {
child = GST_ELEMENT_CAST (children->data);
elementnode = xmlNewChild (childlist, NULL, (xmlChar *) "element", NULL);
gst_object_save_thyself (GST_OBJECT (child), elementnode);
children = g_list_previous (children);
}
return childlist;
}
static void
gst_bin_restore_thyself (GstObject * object, xmlNodePtr self)
{
GstBin *bin = GST_BIN_CAST (object);
xmlNodePtr field = self->xmlChildrenNode;
xmlNodePtr childlist;
while (field) {
if (!strcmp ((char *) field->name, "children")) {
GST_CAT_INFO (GST_CAT_XML, "[%s]: loading children",
GST_ELEMENT_NAME (object));
childlist = field->xmlChildrenNode;
while (childlist) {
if (!strcmp ((char *) childlist->name, "element")) {
/* gst_xml_make_element will gst_bin_add() the element to ourself */
gst_xml_make_element (childlist, GST_OBJECT (bin));
}
childlist = childlist->next;
}
}
field = field->next;
}
if (GST_OBJECT_CLASS (parent_class)->restore_thyself)
(GST_OBJECT_CLASS (parent_class)->restore_thyself) (object, self);
}
#endif /* GST_DISABLE_LOADSAVE */