libs: remove surface's parent context

In commit 18031dc6 surface's parent context is not assigned because of
circular references. Since then (2013), there's has no issue with
subpictures attached to a context, the current only users of this API.

This patch cleans up all of related code with the unused surface's
parent context.

gst-libs/gst/vaapi/gstvaapicontext.c

@@ -34,7 +34,6 @@
 #include "gstvaapidisplay_priv.h"
 #include "gstvaapiobject_priv.h"
 #include "gstvaapisurface.h"
-#include "gstvaapisurface_priv.h"
 #include "gstvaapisurfacepool.h"
 #include "gstvaapisurfaceproxy.h"
 #include "gstvaapivideopool_priv.h"
@@ -61,13 +60,6 @@ ensure_attributes (GstVaapiContext * context)
   return (context->attribs != NULL);
 }
 
-static void
-unref_surface_cb (GstVaapiSurface * surface)
-{
-  gst_vaapi_surface_set_parent_context (surface, NULL);
-  gst_vaapi_object_unref (surface);
-}
-
 static inline gboolean
 context_get_attribute (GstVaapiContext * context, VAConfigAttribType type,
     guint * out_value_ptr)
@@ -141,7 +133,6 @@ context_ensure_surfaces (GstVaapiContext * context)
         cip->chroma_type, cip->width, cip->height, context->attribs->formats);
     if (!surface)
       return FALSE;
-    gst_vaapi_surface_set_parent_context (surface, context);
     g_ptr_array_add (context->surfaces, surface);
     if (!gst_vaapi_video_pool_add_object (context->surfaces_pool, surface))
       return FALSE;
@@ -163,7 +154,7 @@ context_create_surfaces (GstVaapiContext * context)
   num_surfaces = cip->ref_frames + SCRATCH_SURFACES_COUNT;
   if (!context->surfaces) {
     context->surfaces = g_ptr_array_new_full (num_surfaces,
-        (GDestroyNotify) unref_surface_cb);
+        (GDestroyNotify) gst_vaapi_object_unref);
     if (!context->surfaces)
       return FALSE;
   }

gst-libs/gst/vaapi/gstvaapisurface.c

@@ -35,7 +35,6 @@
 #include "gstvaapicontext.h"
 #include "gstvaapiimage.h"
 #include "gstvaapiimage_priv.h"
-#include "gstvaapicontext_overlay.h"
 #include "gstvaapibufferproxy_priv.h"
 
 #define DEBUG 1
@@ -78,7 +77,6 @@ gst_vaapi_surface_destroy (GstVaapiSurface * surface)
   GST_DEBUG ("surface %" GST_VAAPI_ID_FORMAT, GST_VAAPI_ID_ARGS (surface_id));
 
   gst_vaapi_surface_destroy_subpictures (surface);
-  gst_vaapi_surface_set_parent_context (surface, NULL);
 
   if (surface_id != VA_INVALID_SURFACE) {
     GST_VAAPI_DISPLAY_LOCK (display);
@@ -619,42 +617,6 @@ gst_vaapi_surface_get_size (GstVaapiSurface * surface,
     *height_ptr = GST_VAAPI_SURFACE_HEIGHT (surface);
 }
 
-/**
- * gst_vaapi_surface_set_parent_context:
- * @surface: a #GstVaapiSurface
- * @context: a #GstVaapiContext
- *
- * Sets new parent context, or clears any parent context if @context
- * is %NULL. This function owns an extra reference to the context,
- * which will be released when the surface is destroyed.
- */
-void
-gst_vaapi_surface_set_parent_context (GstVaapiSurface * surface,
-    GstVaapiContext * context)
-{
-  g_return_if_fail (surface != NULL);
-
-  surface->parent_context = NULL;
-}
-
-/**
- * gst_vaapi_surface_get_parent_context:
- * @surface: a #GstVaapiSurface
- *
- * Retrieves the parent #GstVaapiContext, or %NULL if there is
- * none. The surface shall still own a reference to the context.
- * i.e. the caller shall not unreference the returned context object.
- *
- * Return value: the parent context, if any.
- */
-GstVaapiContext *
-gst_vaapi_surface_get_parent_context (GstVaapiSurface * surface)
-{
-  g_return_val_if_fail (surface != NULL, NULL);
-
-  return surface->parent_context;
-}
-
 /**
  * gst_vaapi_surface_derive_image:
  * @surface: a #GstVaapiSurface
@@ -1026,8 +988,6 @@ gst_vaapi_surface_query_status (GstVaapiSurface * surface,
  * gst_vaapi_surface_set_subpictures_from_composition:
  * @surface: a #GstVaapiSurface
  * @compostion: a #GstVideoOverlayCompositon
- * @propagate_context: a flag specifying whether to apply composition
- *     to the parent context, if any
  *
  * Helper to update the subpictures from #GstVideoOverlayCompositon. Sending
  * a NULL composition will clear all the current subpictures. Note that this
@@ -1037,17 +997,13 @@ gst_vaapi_surface_query_status (GstVaapiSurface * surface,
  */
 gboolean
 gst_vaapi_surface_set_subpictures_from_composition (GstVaapiSurface * surface,
-    GstVideoOverlayComposition * composition, gboolean propagate_context)
+    GstVideoOverlayComposition * composition)
 {
   GstVaapiDisplay *display;
   guint n, nb_rectangles;
 
   g_return_val_if_fail (surface != NULL, FALSE);
 
-  if (propagate_context && surface->parent_context)
-    return gst_vaapi_context_apply_composition (surface->parent_context,
-        composition);
-
   display = GST_VAAPI_OBJECT_DISPLAY (surface);
   if (!display)
     return FALSE;

gst-libs/gst/vaapi/gstvaapisurface.h

@@ -247,7 +247,7 @@ gst_vaapi_surface_query_status (GstVaapiSurface * surface,
 
 gboolean
 gst_vaapi_surface_set_subpictures_from_composition (GstVaapiSurface * surface,
-    GstVideoOverlayComposition * composition, gboolean propagate_context);
+    GstVideoOverlayComposition * composition);
 
 void
 gst_vaapi_surface_set_buffer_proxy (GstVaapiSurface * surface,

gst-libs/gst/vaapi/gstvaapisurface_priv.h

@@ -47,7 +47,6 @@ struct _GstVaapiSurface
   guint height;
   GstVaapiChromaType chroma_type;
   GPtrArray *subpictures;
-  GstVaapiContext *parent_context;
 };
 
 /**
@@ -109,15 +108,6 @@ struct _GstVaapiSurfaceClass
 #define GST_VAAPI_SURFACE_HEIGHT(surface) \
   (GST_VAAPI_SURFACE (surface)->height)
 
-G_GNUC_INTERNAL
-void
-gst_vaapi_surface_set_parent_context (GstVaapiSurface * surface,
-    GstVaapiContext * context);
-
-G_GNUC_INTERNAL
-GstVaapiContext *
-gst_vaapi_surface_get_parent_context (GstVaapiSurface * surface);
-
 G_END_DECLS
 
 #endif /* GST_VAAPI_SURFACE_PRIV_H */

gst/vaapi/gstvaapipluginutil.c

@@ -482,7 +482,7 @@ gst_vaapi_apply_composition (GstVaapiSurface * surface, GstBuffer * buffer)
   if (cmeta)
     composition = cmeta->overlay;
   return gst_vaapi_surface_set_subpictures_from_composition (surface,
-      composition, TRUE);
+      composition);
 }
 
 gboolean

tests/test-subpicture.c

@@ -149,8 +149,7 @@ main (int argc, char *argv[])
     g_error ("could not create video overlay composition");
   gst_video_overlay_rectangle_unref (overlay);
 
-  if (!gst_vaapi_surface_set_subpictures_from_composition (surface, compo,
-          FALSE))
+  if (!gst_vaapi_surface_set_subpictures_from_composition (surface, compo))
     g_error ("could not create subpictures from video overlay compoition");
 
   gst_vaapi_window_show (window);