vaapidecode: use the query virtual methods in 1.4

GstVideoDecoder, the base class of vaapidecode, added support for
pad queries as virtual methods. This patch enables the use of that
support, while keeping support for lower versions of gstreamer.

This patch is important because GstVideoDecoder takes care of other
queries that might be important in the pipeline managing.

v2: 1) rebase to current master
    2) fix indentation with gst-indent
    3) simplify the patch layout
    4) fix the context query
    5) initialise the filter to NULL
    6) improve the query log message for gst-1.2

https://bugzilla.gnome.org/show_bug.cgi?id=744406

gst/vaapi/gstvaapidecode.c

@@ -113,6 +113,11 @@ static gboolean
 gst_vaapi_decode_input_state_replace (GstVaapiDecode * decode,
     const GstVideoCodecState * new_state);
 
+static gboolean
+gst_vaapidecode_sink_query (GstVideoDecoder * vdec, GstQuery * query);
+static gboolean
+gst_vaapidecode_src_query (GstVideoDecoder * vdec, GstQuery * query);
+
 static void
 gst_vaapi_decoder_state_changed (GstVaapiDecoder * decoder,
     const GstVideoCodecState * codec_state, gpointer user_data)
@@ -844,6 +849,10 @@ gst_vaapidecode_class_init (GstVaapiDecodeClass * klass)
   vdec_class->decide_allocation =
       GST_DEBUG_FUNCPTR (gst_vaapidecode_decide_allocation);
 #endif
+#if GST_CHECK_VERSION(1,4,0)
+  vdec_class->src_query = GST_DEBUG_FUNCPTR (gst_vaapidecode_src_query);
+  vdec_class->sink_query = GST_DEBUG_FUNCPTR (gst_vaapidecode_sink_query);
+#endif
 
   gst_element_class_set_static_metadata (element_class,
       "VA-API decoder",
@@ -940,88 +949,134 @@ gst_vaapidecode_get_caps (GstPad * pad)
   return gst_caps_ref (decode->allowed_caps);
 }
 
+#if !GST_CHECK_VERSION(1,4,0)
 static gboolean
 gst_vaapidecode_query (GST_PAD_QUERY_FUNCTION_ARGS)
 {
   GstVaapiDecode *const decode =
       GST_VAAPIDECODE (gst_pad_get_parent_element (pad));
-  GstVaapiPluginBase *const plugin = GST_VAAPI_PLUGIN_BASE (decode);
+  GstVideoDecoder *const vdec = GST_VIDEO_DECODER (decode);
   gboolean res;
 
-  GST_INFO_OBJECT (decode, "query type %s", GST_QUERY_TYPE_NAME (query));
+  GST_INFO_OBJECT (decode, "query type %s on %s pad",
+      GST_QUERY_TYPE_NAME (query), GST_PAD_IS_SINK (pad) ? "sink" : "src");
+
+  if (GST_PAD_IS_SINK (pad))
+    res = gst_vaapidecode_sink_query (vdec, query);
+  else
+    res = gst_vaapidecode_src_query (vdec, query);
+
+  gst_object_unref (vdec);
+  return res;
+}
+#endif
+
+static gboolean
+gst_vaapidecode_sink_query (GstVideoDecoder * vdec, GstQuery * query)
+{
+  gboolean ret = TRUE;
+  GstVaapiDecode *const decode = GST_VAAPIDECODE (vdec);
+  GstVaapiPluginBase *const plugin = GST_VAAPI_PLUGIN_BASE (decode);
 
   if (gst_vaapi_reply_to_query (query, plugin->display)) {
-    GST_DEBUG ("sharing display %p", plugin->display);
+    GST_DEBUG_OBJECT (decode, "sharing display %p", plugin->display);
-    res = TRUE;
+    return TRUE;
-  } else if (GST_PAD_IS_SINK (pad)) {
+  }
+
   switch (GST_QUERY_TYPE (query)) {
 #if GST_CHECK_VERSION(1,0,0)
     case GST_QUERY_CAPS:{
-        GstCaps *filter, *caps = NULL;
+      GstCaps *caps, *filter = NULL;
+      GstPad *pad = GST_VIDEO_DECODER_SINK_PAD (vdec);
 
       gst_query_parse_caps (query, &filter);
       caps = gst_vaapidecode_get_caps (pad);
 
       if (filter) {
         GstCaps *tmp = caps;
-          caps = gst_caps_intersect_full (filter, tmp,
+        caps = gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);
-              GST_CAPS_INTERSECT_FIRST);
         gst_caps_unref (tmp);
       }
 
-        GST_DEBUG_OBJECT (decode, "Returning sink caps %" GST_PTR_FORMAT, caps);
-
       gst_query_set_caps_result (query, caps);
       gst_caps_unref (caps);
-        res = TRUE;
       break;
     }
 #endif
-      default:
+    default:{
-        res = GST_PAD_QUERY_FUNCTION_CALL (plugin->sinkpad_query, pad,
+#if GST_CHECK_VERSION(1,4,0)
-            parent, query);
+      ret = GST_VIDEO_DECODER_CLASS (gst_vaapidecode_parent_class)->sink_query
+          (vdec, query);
+#else
+      GstPad *pad = GST_VIDEO_DECODER_SINK_PAD (vdec);
+      GstObject *parent = gst_pad_get_parent (pad);
+      ret = GST_PAD_QUERY_FUNCTION_CALL (plugin->sinkpad_query, pad, parent,
+          query);
+      if (parent)
+        gst_object_unref (parent);
+#endif
       break;
     }
-  } else {
+  }
+
+  return ret;
+}
+
+static gboolean
+gst_vaapidecode_src_query (GstVideoDecoder * vdec, GstQuery * query)
+{
+  gboolean ret = TRUE;
+  GstVaapiDecode *const decode = GST_VAAPIDECODE (vdec);
+  GstVaapiPluginBase *const plugin = GST_VAAPI_PLUGIN_BASE (decode);
+
+  if (gst_vaapi_reply_to_query (query, plugin->display)) {
+    GST_DEBUG_OBJECT (decode, "sharing display %p", plugin->display);
+    return TRUE;
+  }
+
   switch (GST_QUERY_TYPE (query)) {
 #if GST_CHECK_VERSION(1,0,0)
     case GST_QUERY_CAPS:{
-        GstCaps *filter, *caps = NULL;
+      GstCaps *caps, *filter = NULL;
+      GstPad *pad = GST_VIDEO_DECODER_SRC_PAD (vdec);
 
       gst_query_parse_caps (query, &filter);
       caps = gst_pad_get_pad_template_caps (pad);
 
       if (filter) {
         GstCaps *tmp = caps;
-          caps = gst_caps_intersect_full (filter, tmp,
+        caps = gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);
-              GST_CAPS_INTERSECT_FIRST);
         gst_caps_unref (tmp);
       }
 
-        GST_DEBUG_OBJECT (decode, "Returning src caps %" GST_PTR_FORMAT, caps);
-
       gst_query_set_caps_result (query, caps);
       gst_caps_unref (caps);
-        res = TRUE;
       break;
     }
 #endif
-      default:
+    default:{
-        res = GST_PAD_QUERY_FUNCTION_CALL (plugin->srcpad_query, pad,
+#if GST_CHECK_VERSION(1,4,0)
-            parent, query);
+      ret = GST_VIDEO_DECODER_CLASS (gst_vaapidecode_parent_class)->src_query
+          (vdec, query);
+#else
+      GstPad *pad = GST_VIDEO_DECODER_SRC_PAD (vdec);
+      GstObject *parent = gst_pad_get_parent (pad);
+      ret = GST_PAD_QUERY_FUNCTION_CALL (plugin->sinkpad_query, pad, parent,
+          query);
+      if (parent)
+        gst_object_unref (parent);
+#endif
       break;
     }
   }
 
-  gst_object_unref (decode);
+  return ret;
-  return res;
 }
 
 static void
 gst_vaapidecode_init (GstVaapiDecode * decode)
 {
   GstVideoDecoder *const vdec = GST_VIDEO_DECODER (decode);
-  GstPad *pad;
 
   gst_vaapi_plugin_base_init (GST_VAAPI_PLUGIN_BASE (decode), GST_CAT_DEFAULT);
 
@@ -1034,8 +1089,9 @@ gst_vaapidecode_init (GstVaapiDecode * decode)
 
   gst_video_decoder_set_packetized (vdec, FALSE);
 
+#if !GST_CHECK_VERSION(1,4,0)
   /* Pad through which data comes in to the element */
-  pad = GST_VAAPI_PLUGIN_BASE_SINK_PAD (decode);
+  GstPad *pad = GST_VAAPI_PLUGIN_BASE_SINK_PAD (decode);
   gst_pad_set_query_function (pad, GST_DEBUG_FUNCPTR (gst_vaapidecode_query));
 #if !GST_CHECK_VERSION(1,0,0)
   gst_pad_set_getcaps_function (pad, gst_vaapidecode_get_caps);
@@ -1044,4 +1100,5 @@ gst_vaapidecode_init (GstVaapiDecode * decode)
   /* Pad through which data goes out of the element */
   pad = GST_VAAPI_PLUGIN_BASE_SRC_PAD (decode);
   gst_pad_set_query_function (pad, GST_DEBUG_FUNCPTR (gst_vaapidecode_query));
+#endif
 }