element: Add API to get the last set context from an element

Elements should override GstElement::set_context() and also call
gst_element_set_context() to keep this context up-to-date with
the very latest context they internally use.
This commit is contained in:
Sebastian Dröge 2013-03-31 11:26:32 +02:00
parent 782511d8f6
commit dd831b8114
5 changed files with 46 additions and 10 deletions

View file

@ -774,6 +774,7 @@ gst_element_get_start_time
gst_element_set_bus
gst_element_get_bus
gst_element_set_context
gst_element_get_context
gst_element_get_factory
gst_element_set_name
gst_element_get_name

View file

@ -189,8 +189,6 @@ struct _GstBinPrivate
guint32 structure_cookie;
GstContext *context;
#if 0
/* cached index */
GstIndex *index;
@ -1144,8 +1142,8 @@ gst_bin_add_func (GstBin * bin, GstElement * element)
* a new clock will be selected */
gst_element_set_clock (element, GST_ELEMENT_CLOCK (bin));
if (bin->priv->context)
gst_element_set_context (element, bin->priv->context);
if (GST_ELEMENT_CAST (bin)->context)
gst_element_set_context (element, GST_ELEMENT_CAST (bin)->context);
#if 0
/* set the cached index on the children */
@ -3966,9 +3964,6 @@ gst_bin_set_context (GstElement * element, GstContext * context)
while (gst_iterator_foreach (children, set_context,
context) == GST_ITERATOR_RESYNC);
gst_iterator_free (children);
GST_OBJECT_LOCK (bin);
gst_context_replace (&bin->priv->context, context);
GST_OBJECT_UNLOCK (bin);
}
static gint

View file

@ -132,7 +132,8 @@ static gboolean gst_element_set_clock_func (GstElement * element,
static void gst_element_set_bus_func (GstElement * element, GstBus * bus);
static gboolean gst_element_post_message_default (GstElement * element,
GstMessage * message);
static void gst_element_set_context_func (GstElement * element,
GstContext * context);
static gboolean gst_element_default_send_event (GstElement * element,
GstEvent * event);
@ -239,6 +240,7 @@ gst_element_class_init (GstElementClass * klass)
klass->send_event = GST_DEBUG_FUNCPTR (gst_element_default_send_event);
klass->numpadtemplates = 0;
klass->post_message = GST_DEBUG_FUNCPTR (gst_element_post_message_default);
klass->set_context = GST_DEBUG_FUNCPTR (gst_element_set_context_func);
klass->elementfactory = NULL;
}
@ -2902,6 +2904,7 @@ gst_element_dispose (GObject * object)
bus_p = &element->bus;
gst_object_replace ((GstObject **) clock_p, NULL);
gst_object_replace ((GstObject **) bus_p, NULL);
gst_context_replace (&element->context, NULL);
GST_OBJECT_UNLOCK (element);
GST_CAT_INFO_OBJECT (GST_CAT_REFCOUNTING, element, "parent class dispose");
@ -3012,9 +3015,17 @@ gst_element_get_bus (GstElement * element)
return result;
}
static void
gst_element_set_context_func (GstElement * element, GstContext * context)
{
GST_OBJECT_LOCK (element);
gst_context_replace (&element->context, context);
GST_OBJECT_UNLOCK (element);
}
/**
* gst_element_set_context:
* @element: a #GstElement to set the bus of.
* @element: a #GstElement to set the context of.
* @context: (transfer none): the #GstContext to set.
*
* Sets the context of the element. Increases the refcount of the context.
@ -3037,3 +3048,28 @@ gst_element_set_context (GstElement * element, GstContext * context)
if (oclass->set_context)
oclass->set_context (element, context);
}
/**
* gst_element_get_context:
* @element: a #GstElement to get the context from.
*
* Gets the current context of the element.
*
* MT safe.
*
* Returns: (transfer full): The current context of the element
*/
GstContext *
gst_element_get_context (GstElement * element)
{
GstContext *context = NULL;
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
GST_OBJECT_LOCK (element);
if (element->context)
context = gst_context_ref (element->context);
GST_OBJECT_UNLOCK (element);
return context;
}

View file

@ -568,8 +568,10 @@ struct _GstElement
GList *sinkpads;
guint32 pads_cookie;
GstContext *context;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
gpointer _gst_reserved[GST_PADDING-1];
};
/**
@ -742,6 +744,7 @@ GstBus * gst_element_get_bus (GstElement * element);
/* context */
void gst_element_set_context (GstElement * element, GstContext * context);
GstContext * gst_element_get_context (GstElement * element);
/* pad management */
gboolean gst_element_add_pad (GstElement *element, GstPad *pad);

View file

@ -387,6 +387,7 @@ EXPORTS
gst_element_get_clock
gst_element_get_compatible_pad
gst_element_get_compatible_pad_template
gst_element_get_context
gst_element_get_factory
gst_element_get_request_pad
gst_element_get_start_time