[pango] Make enum get_type functions thread-safe

[Matthias Clasen <matthiasc src gnome org>]

commit 88692e4eb0a971f6d32da9207c9c91c8d8c7c8d9
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Aug 28 22:06:20 2012 -0400

    Make enum get_type functions thread-safe
    
    Use a more modern, template-based way of calling glib-mkenums,
    and use templates that use g_once_init_enter/leave to be
    thread-safe.

 pango/Makefile.am                 |   29 ++++++++++-------------------
 pango/pango-enum-types.c.template |   36 ++++++++++++++++++++++++++++++++++++
 pango/pango-enum-types.h.template |   24 ++++++++++++++++++++++++
 3 files changed, 70 insertions(+), 19 deletions(-)
---
diff --git a/pango/Makefile.am b/pango/Makefile.am
index 0da59c8..435b495 100644
--- a/pango/Makefile.am
+++ b/pango/Makefile.am
@@ -128,29 +128,18 @@ pangoinclude_HEADERS =	   \
 	pango-enum-types.h
 
 pango-enum-types.h: s-enum-types-h
-s-enum-types-h: $(pango_headers) Makefile.am
+s-enum-types-h: $(pango_headers) Makefile.am pango-enum-types.h.template
 	$(AM_V_GEN) ( cd $(srcdir) && $(GLIB_MKENUMS) \
-			--fhead "#ifndef __PANGO_ENUM_TYPES_H__\n#define __PANGO_ENUM_TYPES_H__\n\n#include <glib-object.h>\n\nG_BEGIN_DECLS\n" \
-			--fprod "/* enumerations from \"@filename \" */\n" \
-			--vhead "GType @enum_name _get_type (void);\n#define @ENUMPREFIX _TYPE_@ENUMSHORT@ (@enum_name _get_type())\n" 	\
-			--ftail "G_END_DECLS\n\n#endif /* __PANGO_ENUM_TYPES_H__ */" \
-		$(pango_headers) ) > tmp-pango-enum-types.h \
-	&& (cmp -s tmp-pango-enum-types.h pango-enum-types.h || cp tmp-pango-enum-types.h pango-enum-types.h ) \
-	&& $(RM) tmp-pango-enum-types.h	\
-	&& echo timestamp > $(@F)
+			 --template pango-enum-types.h.template \
+			$(pango_headers) ) > pango-enum-types.h.tmp \
+			&& mv pango-enum-types.h.tmp pango-enum-types.h
 
 pango-enum-types.c: s-enum-types-c
-s-enum-types-c: $(pango_headers) Makefile.am
+s-enum-types-c: $(pango_headers) Makefile.am pango-enum-types.c.template
 	$(AM_V_GEN) ( cd $(srcdir) && $(GLIB_MKENUMS) \
-			--fhead "#include <pango.h>" \
-			--fprod "\n/* enumerations from \"@filename \" */" \
-			--vhead "GType\n enum_name@_get_type (void)\n{\n  static GType etype = 0;\n  if (etype == 0) {\n    static const G Type@Value values[] = {" 	\
-			--vprod "      { @VALUENAME@, \"@VALUENAME \", \"@valuenick \" }," \
-			--vtail "      { 0, NULL, NULL }\n    };\n    etype = g_ type@_register_static (g_intern_static_string (\"@EnumName \"), values);\n  }\n  return etype;\n}\n" \
-		$(pango_headers) ) > tmp-pango-enum-types.c \
-	&& (cmp -s tmp-pango-enum-types.c pango-enum-types.c || cp tmp-pango-enum-types.c pango-enum-types.c ) \
-	&& $(RM) tmp-pango-enum-types.c \
-	&& echo timestamp > $(@F)
+			 --template pango-enum-types.c.template \
+			$(pango_headers) ) > pango-enum-types.c.tmp \
+			&& mv pango-enum-types.c.tmp pango-enum-types.c
 
 pango-features.h:
 	$(AM_V_GEN) cd $(top_builddir) && ./config.status pango/pango-features.h
@@ -444,6 +433,8 @@ pango_querymodules_LDADD += libpango-$(PANGO_API_VERSION).la $(GLIB_LIBS)
 
 EXTRA_DIST =					\
 	pango-enum-types.h			\
+	pango-enum-types.h.template		\
+	pango-enum-types.c.template		\
 	module-defs.h				\
 	module-defs.h.win32			\
 	module-defs-lang.c.win32		\
diff --git a/pango/pango-enum-types.c.template b/pango/pango-enum-types.c.template
new file mode 100644
index 0000000..c12f4b3
--- /dev/null
+++ b/pango/pango-enum-types.c.template
@@ -0,0 +1,36 @@
+/*** BEGIN file-header ***/
+#include <pango.h>
+
+/*** END file-header ***/
+
+/*** BEGIN file-production ***/
+/* enumerations from "@filename@" */
+/*** END file-production ***/
+
+/*** BEGIN value-header ***/
+GType
+ enum_name@_get_type (void)
+{
+  static volatile gsize g_define_type_id__volatile = 0;
+
+  if (g_once_init_enter (&g_define_type_id__volatile))
+    {
+      static const G Type@Value values[] = {
+/*** END value-header ***/
+
+/*** BEGIN value-production ***/
+        { @VALUENAME@, "@VALUENAME@", "@valuenick@" },
+/*** END value-production ***/
+
+/*** BEGIN value-tail ***/
+        { 0, NULL, NULL }
+      };
+      GType g_define_type_id =
+        g_ type@_register_static (g_intern_static_string ("@EnumName@"), values);
+      g_once_init_leave (&g_define_type_id__volatile, g_define_type_id);
+    }
+
+  return g_define_type_id__volatile;
+}
+
+/*** END value-tail ***/
diff --git a/pango/pango-enum-types.h.template b/pango/pango-enum-types.h.template
new file mode 100644
index 0000000..e5ffbe8
--- /dev/null
+++ b/pango/pango-enum-types.h.template
@@ -0,0 +1,24 @@
+/*** BEGIN file-header ***/
+#ifndef __PANGO_ENUM_TYPES_H__
+#define __PANGO_ENUM_TYPES_H__
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+/*** END file-header ***/
+
+/*** BEGIN file-production ***/
+
+/* enumerations from "@filename@" */
+/*** END file-production ***/
+
+/*** BEGIN value-header ***/
+GType @enum_name _get_type (void) G_GNUC_CONST;
+#define @ENUMPREFIX _TYPE_@ENUMSHORT@ (@enum_name _get_type ())
+/*** END value-header ***/
+
+/*** BEGIN file-tail ***/
+G_END_DECLS
+
+#endif /* __PANGO_ENUM_TYPES_H__ */
+/*** END file-tail ***/