Add gst_pad_set_active_recursive().

Original commit message from CVS:
* docs/gst/gstreamer-sections.txt:
* docs/gst/tmpl/gstpad.sgml:
* gst/gstpad.c: (gst_pad_set_active_recursive):
* gst/gstpad.h:
Add gst_pad_set_active_recursive().

ChangeLog

@@ -1,3 +1,11 @@
+2005-01-11  Ronald S. Bultje  <rbultje@ronald.bitfreak.net>
+
+	* docs/gst/gstreamer-sections.txt:
+	* docs/gst/tmpl/gstpad.sgml:
+	* gst/gstpad.c: (gst_pad_set_active_recursive):
+	* gst/gstpad.h:
+	  Add gst_pad_set_active_recursive().
+
 2005-01-10  Thomas Vander Stichele  <thomas at apestaart dot org>
 
 	* docs/random/release:

docs/gst/gstreamer-sections.txt

@@ -974,6 +974,7 @@ gst_pad_set_name
 gst_pad_get_name
 gst_pad_get_direction
 gst_pad_set_active
+gst_pad_set_active_recursive
 gst_pad_is_active
 gst_pad_set_element_private
 gst_pad_get_element_private

docs/gst/tmpl/gstpad.sgml

@@ -529,6 +529,15 @@ Checks if the pad is a sink pad.
 @active: 
 
 
+<!-- ##### FUNCTION gst_pad_set_active_recursive ##### -->
+<para>
+
+</para>
+
+@pad: 
+@active: 
+
+
 <!-- ##### FUNCTION gst_pad_is_active ##### -->
 <para>
 

gst/gstpad.c

@@ -480,6 +480,52 @@ gst_pad_set_active (GstPad * pad, gboolean active)
   g_object_notify (G_OBJECT (realpad), "active");
 }
 
+/**
+ * gst_pad_set_active_recursive:
+ * @pad: the #GstPad to activate or deactivate.
+ * @active: TRUE to activate the pad.
+ *
+ * Activates or deactivates the given pad and all internally linked
+ * pads upstream until it finds an element with multiple source pads.
+ */
+void
+gst_pad_set_active_recursive (GstPad * pad, gboolean active)
+{
+  GstElement *parent;
+  const GList *int_links;
+
+  g_return_if_fail (GST_IS_PAD (pad));
+  g_return_if_fail (GST_PAD_IS_SRC (pad));
+
+  GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
+      "Recursively %s pad %s:%s", active ? "activating" : "deactivating",
+      GST_DEBUG_PAD_NAME (pad));
+
+  gst_pad_set_active (pad, active);
+
+  /* If we have more than one sourcepad, then the other pads should
+   * possibly be kept active. FIXME: maybe we should recurse
+   * activation if any one pad is active and recurse deactivation
+   * if no single pad is active? */
+  parent = gst_pad_get_parent (pad);
+  if (!parent || parent->numsrcpads > 1)
+    return;
+
+  for (int_links = gst_pad_get_internal_links (pad);
+      int_links; int_links = g_list_next (int_links)) {
+    GstPad *sinkpad = GST_PAD (int_links->data);
+    GstPad *peer = GST_PAD_PEER (sinkpad);
+
+    GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, sinkpad,
+        "Recursing %s on pad %s:%s",
+        active ? "activation" : "deactivation", GST_DEBUG_PAD_NAME (sinkpad));
+
+    gst_pad_set_active (sinkpad, active);
+    if (peer)
+      gst_pad_set_active_recursive (peer, active);
+  }
+}
+
 /**
  * gst_pad_is_active:
  * @pad: the #GstPad to query

gst/gstpad.h

@@ -366,6 +366,7 @@ G_CONST_RETURN gchar*	gst_pad_get_name			(GstPad *pad);
 GstPadDirection		gst_pad_get_direction			(GstPad *pad);
 
 void			gst_pad_set_active			(GstPad *pad, gboolean active);
+void			gst_pad_set_active_recursive		(GstPad *pad, gboolean active);
 gboolean		gst_pad_is_active			(GstPad *pad);
 
 void			gst_pad_set_element_private		(GstPad *pad, gpointer priv);