[pango] Make static data thread safe in pangowin32-fontmap.c

[Behdad Esfahbod <behdad src gnome org>]

commit f81174dd4f8f8601bbf1066ba9757a4a13bb3c60
Author: Alessandro Pignotti <a pignotti sssup it>
Date:   Wed May 25 16:58:22 2011 +0200

    Make static data thread safe in pangowin32-fontmap.c

 pango/pangowin32-fontmap.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)
---
diff --git a/pango/pangowin32-fontmap.c b/pango/pangowin32-fontmap.c
index 9cfa161..36456fc 100644
--- a/pango/pangowin32-fontmap.c
+++ b/pango/pangowin32-fontmap.c
@@ -696,10 +696,8 @@ pango_win32_font_map_for_display (void)
   /* Make sure that the type system is initialized */
   g_type_init ();
 
-  if (default_fontmap != NULL)
-    return PANGO_FONT_MAP (default_fontmap);
-
-  default_fontmap = g_object_new (PANGO_TYPE_WIN32_FONT_MAP, NULL);
+  if (g_once_init_enter ((gsize*)&default_fontmap))
+    g_once_init_leave((gsize*)&default_fontmap, (gsize)g_object_new (PANGO_TYPE_WIN32_FONT_MAP, NULL));
 
   return PANGO_FONT_MAP (default_fontmap);
 }