decodebin2: Only prevent to autoplug the same parser multiple times for the same...

Parsers are the only element class that are not changing the data and
could lead to an infinite loop. Other element classes like demuxers,
e.g. id3demux, can be used multiple times in a row and sometimes are.

diff --git a/gst/playback/gstdecodebin2.c b/gst/playback/gstdecodebin2.c
index 7b8fbc2..882d53f 100644 (file)
--- a/gst/playback/gstdecodebin2.c
+++ b/gst/playback/gstdecodebin2.c
@@ -1667,8 +1667,6 @@ connect_pad (GstDecodeBin * dbin, GstElement * src, GstDecodePad * dpad,
     GstElement *element;
     GstPad *sinkpad;
     gboolean subtitle;
-    gboolean skip = FALSE;
-    GList *l;
 
     /* Set dpad target to pad again, it might've been unset
      * below but we came back here because something failed
@@ -1680,27 +1678,35 @@ connect_pad (GstDecodeBin * dbin, GstElement * src, GstDecodePad * dpad,
     /* Remove selected factory from the list. */
     g_value_array_remove (factories, 0);
 
-    /* First check if this is a factory for which we have already
-     * created an element in this chain. If we have, we skip this
-     * factory because it will lead to an infinite loop. Examples
-     * for this are parsers that accept their own src caps on the
-     * sinkpad again.
+    /* If the factory is for a parser we first check if the factory
+     * was already used for the current chain. If it was used already
+     * we would otherwise create an infinite loop here because the
+     * parser apparently accepts its own output as input.
+     * This is only done for parsers because it's perfectly valid
+     * to have other element classes after each other because a
+     * parser is the only one that does not change the data. A
+     * valid example for this would be multiple id3demux in a row.
      */
-    CHAIN_MUTEX_LOCK (chain);
-    for (l = chain->elements; l; l = l->next) {
-      GstElement *otherelement = GST_ELEMENT_CAST (l->data);
+    if (strstr (gst_element_factory_get_klass (factory), "Parser")) {
+      gboolean skip = FALSE;
+      GList *l;
 
-      if (gst_element_get_factory (otherelement) == factory) {
-        skip = TRUE;
-        break;
+      CHAIN_MUTEX_LOCK (chain);
+      for (l = chain->elements; l; l = l->next) {
+        GstElement *otherelement = GST_ELEMENT_CAST (l->data);
+
+        if (gst_element_get_factory (otherelement) == factory) {
+          skip = TRUE;
+          break;
+        }
+      }
+      CHAIN_MUTEX_UNLOCK (chain);
+      if (skip) {
+        GST_DEBUG_OBJECT (dbin,
+            "Skipping factory '%s' because it was already used in this chain",
+            gst_plugin_feature_get_name (GST_PLUGIN_FEATURE_CAST (factory)));
+        continue;
       }
-    }
-    CHAIN_MUTEX_UNLOCK (chain);
-    if (skip) {
-      GST_DEBUG_OBJECT (dbin,
-          "Skipping factory '%s' because it was already used in this chain",
-          gst_plugin_feature_get_name (GST_PLUGIN_FEATURE_CAST (factory)));
-      continue;
     }
 
     /* emit autoplug-select to see what we should do with it. */