/**
* helper for gst_goo_util_find_goo_component() to iterate and search
* the members of a bin
*/
static GooComponent *
find_goo_component_in_bin (GstBin *bin, SearchContext *ctx)
{
GstIterator *itr;
gpointer item;
GooComponent *component = NULL;
GST_INFO ("bin=%s (%s)", gst_element_get_name (bin), G_OBJECT_TYPE_NAME (bin));
/* note: we don't handle the case of the underlying data structure changing
* while iterating.. we just bail out and the user needs to restart.
*/
for( itr = gst_bin_iterate_elements (bin);
gst_iterator_next (itr, &item) == GST_ITERATOR_OK && !component;
gst_object_unref (item) )
{
GstElement *elem = GST_ELEMENT (item);
component = check_for_goo_component (elem, ctx);
if( component == NULL )
{
component = find_goo_component (elem, ctx);
}
}
gst_iterator_free (itr);
return component;
}
/**
* Utility to search the pipeline that @elem is a member of find the element
* with the specified @type
*
* Note: if underlying pipeline structure changes as we iterate thru it,
* it could cause us to bail out early before iterating thru the entire
* pipeline.. basically the caller should listen for changes to the pipeline
* structure, and call this again if new elements are added and the caller
* hasn't yet found the peer element it is looking for.
*/
GooComponent *
gst_goo_util_find_goo_component (GstElement *elem, GType type)
{
SearchContext ctx; /* only needed until this fxn returns, so alloc on stack */
GST_INFO("type=%s", g_type_name(type));
ctx.type = type;
ctx.visited_nodes = g_hash_table_new (g_direct_hash, g_direct_equal);
GooComponent *component = find_goo_component (elem, &ctx);
g_hash_table_destroy (ctx.visited_nodes);
return component;
}
/**
* recursively iterate all our pads and search adjacent elements
*/
static GooComponent *
find_goo_component_in_elem (GstElement *elem, SearchContext *ctx)
{
GstIterator *itr;
gpointer item;
GooComponent *component = NULL;
/* check if we've already examined this element, to prevent loops: */
if (already_visited (ctx->visited_nodes, elem))
{
GST_INFO ("already visited elem=%s (%s)", gst_element_get_name (elem), G_OBJECT_TYPE_NAME (elem));
return NULL;
}
GST_INFO ("elem=%s (%s)", gst_element_get_name (elem), G_OBJECT_TYPE_NAME (elem));
/* note: we don't handle the case of the underlying data structure changing
* while iterating.. we just bail out and the user needs to restart.
*/
for( itr = gst_element_iterate_pads (elem);
gst_iterator_next (itr, &item) == GST_ITERATOR_OK && !component;
gst_object_unref (item) )
{
GstElement *adjacent_elem = NULL;
GstPad *pad = GST_PAD (item);
GstPad *peer = gst_pad_get_peer (pad);
GST_INFO ("found pad: %s (%s)", gst_pad_get_name (pad), G_OBJECT_TYPE_NAME (pad));
if (G_UNLIKELY (peer == NULL))
{
GST_INFO ("NULL peer.. not connected yet?");
continue;
}
/* in the case of GstGhostPad (and probably other proxy pads)
* the parent is actually the pad we are a proxy for, so
* keep looping until we find the GstElement
*/
while(TRUE)
{
GstObject *obj = gst_pad_get_parent (peer);
if( GST_IS_PAD(obj) )
{
gst_object_unref (peer);
peer = GST_PAD (obj);
}
else
{
adjacent_elem = GST_ELEMENT (obj);
break;
}
}
if (G_UNLIKELY (adjacent_elem == NULL))
{
gst_object_unref (peer);
GST_INFO ("Cannot find a adjacent element");
continue;
}
GST_INFO ("found adjacent_elem: %s", gst_element_get_name (adjacent_elem));
component = find_goo_component (adjacent_elem, ctx);
/* cleanup: */
gst_object_unref (adjacent_elem);
gst_object_unref (peer);
}
gst_iterator_free (itr);
return component;
}
