winegstreamer: Introduce find_element_factories.

dlls/winegstreamer/unix_private.h

@@ -35,7 +35,10 @@ extern NTSTATUS wg_init_gstreamer(void *args) DECLSPEC_HIDDEN;
 
 extern GstStreamType stream_type_from_caps(GstCaps *caps) DECLSPEC_HIDDEN;
 extern GstElement *create_element(const char *name, const char *plugin_set) DECLSPEC_HIDDEN;
-extern GstElement *find_element(GstElementFactoryListType type, GstCaps *src_caps, GstCaps *sink_caps) DECLSPEC_HIDDEN;
+extern GList *find_element_factories(GstElementFactoryListType type, GstRank min_rank,
+        GstCaps *element_sink_caps, GstCaps *element_src_caps) DECLSPEC_HIDDEN;
+extern GstElement *find_element(GstElementFactoryListType type,
+        GstCaps *element_sink_caps, GstCaps *element_src_caps) DECLSPEC_HIDDEN;
 extern bool append_element(GstElement *container, GstElement *element, GstElement **first, GstElement **last) DECLSPEC_HIDDEN;
 extern bool link_src_to_sink(GstPad *src_pad, GstPad *sink_pad) DECLSPEC_HIDDEN;
 extern bool link_src_to_element(GstPad *src_pad, GstElement *element) DECLSPEC_HIDDEN;

dlls/winegstreamer/unixlib.c

@@ -78,32 +78,50 @@ GstElement *create_element(const char *name, const char *plugin_set)
     return element;
 }
 
-GstElement *find_element(GstElementFactoryListType type, GstCaps *src_caps, GstCaps *sink_caps)
+GList *find_element_factories(GstElementFactoryListType type, GstRank min_rank,
+        GstCaps *element_sink_caps, GstCaps *element_src_caps)
 {
-    GstElement *element = NULL;
-    GList *tmp, *transforms;
-    const gchar *name;
+    GList *tmp, *factories = NULL;
 
-    if (!(transforms = gst_element_factory_list_get_elements(type, GST_RANK_MARGINAL)))
+    if (!(factories = gst_element_factory_list_get_elements(type, min_rank)))
         goto done;
 
-    if (src_caps)
+    if (element_sink_caps)
     {
-        tmp = gst_element_factory_list_filter(transforms, src_caps, GST_PAD_SINK, FALSE);
-        gst_plugin_feature_list_free(transforms);
-        if (!(transforms = tmp))
+        tmp = gst_element_factory_list_filter(factories, element_sink_caps, GST_PAD_SINK, FALSE);
+        gst_plugin_feature_list_free(factories);
+        if (!(factories = tmp))
             goto done;
     }
 
-    if (sink_caps)
+    if (element_src_caps)
     {
-        tmp = gst_element_factory_list_filter(transforms, sink_caps, GST_PAD_SRC, FALSE);
-        gst_plugin_feature_list_free(transforms);
-        if (!(transforms = tmp))
+        tmp = gst_element_factory_list_filter(factories, element_src_caps, GST_PAD_SRC, FALSE);
+        gst_plugin_feature_list_free(factories);
+        if (!(factories = tmp))
             goto done;
     }
 
-    transforms = g_list_sort(transforms, gst_plugin_feature_rank_compare_func);
+    factories = g_list_sort(factories, gst_plugin_feature_rank_compare_func);
+
+done:
+    if (!factories)
+        GST_WARNING("Failed to find any element factory matching "
+                "type %"G_GUINT64_FORMAT"x, caps %"GST_PTR_FORMAT" / %"GST_PTR_FORMAT".",
+                type, element_sink_caps, element_src_caps);
+
+    return factories;
+}
+
+GstElement *find_element(GstElementFactoryListType type, GstCaps *element_sink_caps, GstCaps *element_src_caps)
+{
+    GstElement *element = NULL;
+    GList *tmp, *transforms;
+    const gchar *name;
+
+    if (!(transforms = find_element_factories(type, GST_RANK_MARGINAL, element_sink_caps, element_src_caps)))
+        return NULL;
+
     for (tmp = transforms; tmp != NULL && element == NULL; tmp = tmp->next)
     {
         name = gst_plugin_feature_get_name(GST_PLUGIN_FEATURE(tmp->data));
@@ -120,20 +138,14 @@ GstElement *find_element(GstElementFactoryListType type, GstCaps *src_caps, GstC
         if (!(element = gst_element_factory_create(GST_ELEMENT_FACTORY(tmp->data), NULL)))
             GST_WARNING("Failed to create %s element.", name);
     }
+
     gst_plugin_feature_list_free(transforms);
 
-done:
     if (element)
-    {
         GST_DEBUG("Created %s element %p.", name, element);
-    }
     else
-    {
-        gchar *src_str = gst_caps_to_string(src_caps), *sink_str = gst_caps_to_string(sink_caps);
-        GST_WARNING("Failed to create element matching caps %s / %s.", src_str, sink_str);
-        g_free(sink_str);
-        g_free(src_str);
-    }
+        GST_WARNING("Failed to create element matching caps %"GST_PTR_FORMAT" / %"GST_PTR_FORMAT".",
+                element_sink_caps, element_src_caps);
 
     return element;
 }