playback: When going from NULL->READY check if the registry has new features

This makes it possible to use newly installed plugins after going back
to NULL instead of requiring a new instance.

Fixes bug #599266.

gst/playback/gstdecodebin2.c

@@ -149,6 +149,7 @@ struct _GstDecodeBin
   GstDecodeChain *decode_chain; /* Top level decode chain */
   gint nbpads;                  /* unique identifier for source pads */
 
+  guint32 factories_cookie;     /* Cookie from last time when factories was updated */
   GValueArray *factories;       /* factories we can use for selecting elements */
 
   GMutex *subtitle_lock;        /* Protects changes to subtitles and encoding */
@@ -845,6 +846,8 @@ gst_decode_bin_init (GstDecodeBin * decode_bin)
   /* first filter out the interesting element factories */
   decode_bin->factories =
       gst_factory_list_get_elements (GST_FACTORY_LIST_DECODER);
+  decode_bin->factories_cookie =
+      gst_default_registry_get_feature_list_cookie ();
 
   /* we create the typefind element only once */
   decode_bin->typefind = gst_element_factory_make ("typefind", "typefind");
@@ -3229,6 +3232,15 @@ gst_decode_bin_change_state (GstElement * element, GstStateChange transition)
     case GST_STATE_CHANGE_NULL_TO_READY:
       if (dbin->typefind == NULL)
         goto missing_typefind;
+      if (dbin->factories_cookie !=
+          gst_default_registry_get_feature_list_cookie ()) {
+        if (dbin->factories)
+          g_value_array_free (dbin->factories);
+        dbin->factories =
+            gst_factory_list_get_elements (GST_FACTORY_LIST_DECODER);
+        dbin->factories_cookie =
+            gst_default_registry_get_feature_list_cookie ();
+      }
       break;
     case GST_STATE_CHANGE_READY_TO_PAUSED:
       DYN_LOCK (dbin);

gst/playback/gstplaybin2.c

@@ -373,6 +373,7 @@ struct _GstPlayBin
   /* if we are shutting down or not */
   gint shutdown;
 
+  guint32 elements_cookie;
   GValueArray *elements;        /* factories we can use for selecting elements */
 
   gboolean have_selector;       /* set to FALSE when we fail to create an
@@ -1122,6 +1123,7 @@ gst_play_bin_init (GstPlayBin * playbin)
   /* first filter out the interesting element factories */
   type = GST_FACTORY_LIST_DECODER | GST_FACTORY_LIST_SINK;
   playbin->elements = gst_factory_list_get_elements (type);
+  playbin->elements_cookie = gst_default_registry_get_feature_list_cookie ();
   gst_factory_list_debug (playbin->elements);
 
   /* add sink */
@@ -2962,6 +2964,17 @@ gst_play_bin_change_state (GstElement * element, GstStateChange transition)
   playbin = GST_PLAY_BIN (element);
 
   switch (transition) {
+    case GST_STATE_CHANGE_NULL_TO_READY:
+      if (playbin->elements_cookie !=
+          gst_default_registry_get_feature_list_cookie ()) {
+        if (playbin->elements)
+          g_value_array_free (playbin->elements);
+        playbin->elements =
+            gst_factory_list_get_elements (GST_FACTORY_LIST_DECODER);
+        playbin->elements_cookie =
+            gst_default_registry_get_feature_list_cookie ();
+      }
+      break;
     case GST_STATE_CHANGE_READY_TO_PAUSED:
       GST_LOG_OBJECT (playbin, "clearing shutdown flag");
       g_atomic_int_set (&playbin->shutdown, 0);

gst/playback/gsturidecodebin.c

@@ -68,6 +68,7 @@ struct _GstURIDecodeBin
 
   GMutex *lock;                 /* lock for constructing */
 
+  guint32 factories_cookie;
   GValueArray *factories;       /* factories we can use for selecting elements */
 
   gchar *uri;
@@ -471,6 +472,7 @@ gst_uri_decode_bin_init (GstURIDecodeBin * dec, GstURIDecodeBinClass * klass)
 {
   /* first filter out the interesting element factories */
   dec->factories = gst_factory_list_get_elements (GST_FACTORY_LIST_DECODER);
+  dec->factories_cookie = gst_default_registry_get_feature_list_cookie ();
 
   dec->lock = g_mutex_new ();
 
@@ -2040,6 +2042,17 @@ gst_uri_decode_bin_change_state (GstElement * element,
   decoder = GST_URI_DECODE_BIN (element);
 
   switch (transition) {
+    case GST_STATE_CHANGE_NULL_TO_READY:
+      if (decoder->factories_cookie !=
+          gst_default_registry_get_feature_list_cookie ()) {
+        if (decoder->factories)
+          g_value_array_free (decoder->factories);
+        decoder->factories =
+            gst_factory_list_get_elements (GST_FACTORY_LIST_DECODER);
+        decoder->factories_cookie =
+            gst_default_registry_get_feature_list_cookie ();
+      }
+      break;
     case GST_STATE_CHANGE_READY_TO_PAUSED:
       if (!setup_source (decoder))
         goto source_failed;