buffer: remove subbuffer subclass

Move the parent buffer pointer into the GstBuffer struct so that we can
remove the subbuffer class and type. This is interesting because it allows us to
more naturally implement methods to get the real type and parent
of a subbuffer (See #545501).
It should also be slightly faster because there is no extra object hierarchy to
initialize and free.

diff --git a/gst/gstbuffer.c b/gst/gstbuffer.c
index b56b16c..beec71b 100644 (file)
--- a/gst/gstbuffer.c
+++ b/gst/gstbuffer.c
@@ -122,9 +122,7 @@
 
 static void gst_buffer_finalize (GstBuffer * buffer);
 static GstBuffer *_gst_buffer_copy (GstBuffer * buffer);
-static GType gst_subbuffer_get_type (void);
 
-static GType _gst_subbuffer_type = 0;
 static GType _gst_buffer_type = 0;
 
 void
@@ -134,7 +132,6 @@ _gst_buffer_initialize (void)
    * done from multiple threads;
    * see http://bugzilla.gnome.org/show_bug.cgi?id=304551 */
   g_type_class_ref (gst_buffer_get_type ());
-  g_type_class_ref (gst_subbuffer_get_type ());
 }
 
 #define _do_init \
@@ -165,6 +162,9 @@ gst_buffer_finalize (GstBuffer * buffer)
 
   gst_caps_replace (&GST_BUFFER_CAPS (buffer), NULL);
 
+  if (buffer->parent)
+    gst_buffer_unref (buffer->parent);
+
 /*   ((GstMiniObjectClass *) */
 /*       gst_buffer_parent_class)->finalize (GST_MINI_OBJECT_CAST (buffer)); */
 }
@@ -454,55 +454,7 @@ gst_buffer_make_metadata_writable (GstBuffer * buf)
   return ret;
 }
 
-typedef struct _GstSubBuffer GstSubBuffer;
-typedef struct _GstSubBufferClass GstSubBufferClass;
-
-#define GST_IS_SUBBUFFER(obj)   (G_TYPE_CHECK_INSTANCE_TYPE ((obj), _gst_subbuffer_type))
-#define GST_SUBBUFFER_CAST(obj) ((GstSubBuffer *)(obj))
-
-struct _GstSubBuffer
-{
-  GstBuffer buffer;
-
-  GstBuffer *parent;
-};
-
-struct _GstSubBufferClass
-{
-  GstBufferClass buffer_class;
-};
-
-static void gst_subbuffer_finalize (GstSubBuffer * buffer);
-
-#define _do_init_sub \
-{ \
-  _gst_subbuffer_type = g_define_type_id; \
-}
-
-G_DEFINE_TYPE_WITH_CODE (GstSubBuffer, gst_subbuffer, GST_TYPE_BUFFER,
-    _do_init_sub);
-
-static void
-gst_subbuffer_class_init (GstSubBufferClass * klass)
-{
-  klass->buffer_class.mini_object_class.finalize =
-      (GstMiniObjectFinalizeFunction) gst_subbuffer_finalize;
-}
-
-static void
-gst_subbuffer_finalize (GstSubBuffer * buffer)
-{
-  gst_buffer_unref (buffer->parent);
-
-  ((GstMiniObjectClass *) gst_subbuffer_parent_class)->finalize
-      (GST_MINI_OBJECT_CAST (buffer));
-}
-
-static void
-gst_subbuffer_init (GstSubBuffer * instance)
-{
-  GST_BUFFER_FLAG_SET (GST_BUFFER_CAST (instance), GST_BUFFER_FLAG_READONLY);
-}
+#define GST_IS_SUBBUFFER(obj)   (GST_BUFFER_CAST(obj)->parent != NULL)
 
 /**
  * gst_buffer_create_sub:
@@ -527,7 +479,7 @@ gst_subbuffer_init (GstSubBuffer * instance)
 GstBuffer *
 gst_buffer_create_sub (GstBuffer * buffer, guint offset, guint size)
 {
-  GstSubBuffer *subbuffer;
+  GstBuffer *subbuffer;
   GstBuffer *parent;
   gboolean complete;
 
@@ -537,15 +489,16 @@ gst_buffer_create_sub (GstBuffer * buffer, guint offset, guint size)
 
   /* find real parent */
   if (GST_IS_SUBBUFFER (buffer)) {
-    parent = GST_SUBBUFFER_CAST (buffer)->parent;
+    parent = buffer->parent;
   } else {
     parent = buffer;
   }
   gst_buffer_ref (parent);
 
   /* create the new buffer */
-  subbuffer = (GstSubBuffer *) gst_mini_object_new (_gst_subbuffer_type);
+  subbuffer = gst_buffer_new ();
   subbuffer->parent = parent;
+  GST_BUFFER_FLAG_SET (GST_BUFFER_CAST (subbuffer), GST_BUFFER_FLAG_READONLY);
 
   GST_CAT_LOG (GST_CAT_BUFFER, "new subbuffer %p (parent %p)", subbuffer,
       parent);
@@ -616,8 +569,7 @@ gst_buffer_is_span_fast (GstBuffer * buf1, GstBuffer * buf2)
 
   /* it's only fast if we have subbuffers of the same parent */
   return (GST_IS_SUBBUFFER (buf1) &&
-      GST_IS_SUBBUFFER (buf2) &&
-      (GST_SUBBUFFER_CAST (buf1)->parent == GST_SUBBUFFER_CAST (buf2)->parent)
+      GST_IS_SUBBUFFER (buf2) && (buf1->parent == buf2->parent)
       && ((buf1->data + buf1->size) == buf2->data));
 }
 
@@ -657,7 +609,7 @@ gst_buffer_span (GstBuffer * buf1, guint32 offset, GstBuffer * buf2,
 
   /* if the two buffers have the same parent and are adjacent */
   if (gst_buffer_is_span_fast (buf1, buf2)) {
-    GstBuffer *parent = GST_SUBBUFFER_CAST (buf1)->parent;
+    GstBuffer *parent = buf1->parent;
 
     /* we simply create a subbuffer of the common parent */
     newbuf = gst_buffer_create_sub (parent,

diff --git a/gst/gstbuffer.h b/gst/gstbuffer.h
index f6d96e9..4314d0b 100644 (file)
--- a/gst/gstbuffer.h
+++ b/gst/gstbuffer.h
@@ -258,6 +258,7 @@ typedef enum {
  *     When the buffer is freed, this data will freed with @free_func.
  * @free_func: a custom function that will be called with @malloc_data, defaults
  *     to g_free(). Since 0.10.22.
+ * @parent: the parent buffer if this is a subbuffer. Since 0.10.26.
  *
  * The structure of a #GstBuffer. Use the associated macros to access the public
  * variables.
@@ -283,10 +284,12 @@ struct _GstBuffer {
 
   guint8                *malloc_data;
 
+  /* ABI Added */
   GFreeFunc              free_func;
+  GstBuffer             *parent;
 
   /*< private >*/
-  gpointer _gst_reserved[GST_PADDING - 1];
+  gpointer _gst_reserved[GST_PADDING - 2];
 };
 
 struct _GstBufferClass {