gst/gstutils.h: Make GST_BOILERPLATE thread-safe if building with GLib 2.14 or newer.

Original commit message from CVS:
* gst/gstutils.h:
Make GST_BOILERPLATE thread-safe if building with GLib 2.14 or newer.

diff --git a/ChangeLog b/ChangeLog
index 4f12564..28280d2 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2008-05-08  Sebastian Dröge  <slomo@circular-chaos.org>
 
+       * gst/gstutils.h:
+       Make GST_BOILERPLATE thread-safe if building with GLib 2.14 or newer.
+
+2008-05-08  Sebastian Dröge  <slomo@circular-chaos.org>
+
        Based on a patch by: Sjoerd Simons <sjoerd at luon dot net>
 
        * libs/gst/base/gstbasetransform.c:

diff --git a/gst/gstutils.h b/gst/gstutils.h
index 9266012..a2f2ece 100644 (file)
--- a/gst/gstutils.h
+++ b/gst/gstutils.h
@@ -88,6 +88,15 @@ GType gst_type_register_static_full (GType parent_type,
 /* Macros for defining classes.  Ideas taken from Bonobo, which took theirs
    from Nautilus and GOB. */
 
+/* FIXME: Use g_once_init_* unconditionally once we depend on glib 2.14 */
+#if GLIB_CHECK_VERSION (2, 14, 0)
+#define __gst_once_init_enter(val) (g_once_init_enter (val))
+#define __gst_once_init_leave(val,newval) (g_once_init_leave (val, newval))
+#else
+#define __gst_once_init_enter(val) (G_UNLIKELY (*(val) == 0))
+#define __gst_once_init_leave(val,newval) (*(val) = newval)
+#endif
+
 /**
  * GST_BOILERPLATE_FULL:
  * @type: the name of the type struct
@@ -128,10 +137,11 @@ GType type_as_function ## _get_type (void);                               \
 GType                                                                  \
 type_as_function ## _get_type (void)                                   \
 {                                                                      \
-  static GType object_type = 0;                                                \
-  if (G_UNLIKELY (object_type == 0)) {                                 \
-    object_type = gst_type_register_static_full (parent_type_macro, #type,     \
-       sizeof (type ## Class),                                 \
+  static volatile GType object_type = 0;                               \
+  if (__gst_once_init_enter ((gsize *) &object_type)) {                        \
+    GType _type;                                                       \
+    _type = gst_type_register_static_full (parent_type_macro, #type,   \
+       sizeof (type ## Class),                                         \
         type_as_function ## _base_init,                                        \
         NULL,            /* base_finalize */                           \
         type_as_function ## _class_init_trampoline,                    \
@@ -142,7 +152,8 @@ type_as_function ## _get_type (void)                                        \
         (GInstanceInitFunc) type_as_function ## _init,                  \
         NULL,                                                           \
         (GTypeFlags) 0);                                               \
-    additional_initializations (object_type);                          \
+    additional_initializations (_type);                                        \
+    __gst_once_init_leave ((gsize *) &object_type, (gsize) _type);      \
   }                                                                    \
   return object_type;                                                  \
 }