X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=blobdiff_plain;f=libdocument%2Fev-document.h;h=3ab918adb6f6724e20a1c3d2c099a1efcf601ebe;hb=7d8aa7727a74f84c6fc473dbe87a923fd2c25959;hp=e07e3a22a8a5e99a17c8c68aa59ea176669a4632;hpb=95395e6b0e5e174a43931605043dba668232d331;p=evince.git

diff --git a/libdocument/ev-document.h b/libdocument/ev-document.h
index e07e3a22..3ab918ad 100644
--- a/libdocument/ev-document.h
+++ b/libdocument/ev-document.h
@@ -19,6 +19,10 @@
  *  $Id$
  */
 
+#if !defined (__EV_EVINCE_DOCUMENT_H_INSIDE__) && !defined (EVINCE_COMPILATION)
+#error "Only <evince-document.h> can be included directly."
+#endif
+
 #ifndef EV_DOCUMENT_H
 #define EV_DOCUMENT_H
 
@@ -178,7 +182,7 @@ static void     backend_name##_class_intern_init (gpointer klass)		\
 G_MODULE_EXPORT GType								\
 register_evince_backend (GTypeModule *module)					\
 {										\
-	static const GTypeInfo our_info = {  				        \
+	const GTypeInfo our_info = {  				        \
 		sizeof (BackendName##Class),					\
 		NULL, /* base_init */						\
 		NULL, /* base_finalize */					\
@@ -234,8 +238,38 @@ type_name##_get_type (void)
 	}                                                                             \
 	return g_define_type_id__volatile;                                            \
 }
- 
 
+/* A convenience macro for GTypeInterface definitions, which declares
+ * a default vtable initialization function and defines a *_get_type()
+ * function.
+ *
+ * The macro expects the interface initialization function to have the
+ * name <literal>t_n ## _default_init</literal>, and the interface
+ * structure to have the name <literal>TN ## Interface</literal>.
+ */
+#define EV_DEFINE_INTERFACE(TypeName, type_name, TYPE_PREREQ)	                             \
+static void     type_name##_class_init        (TypeName##Iface *klass);                      \
+                                                                                             \
+GType                                                                                        \
+type_name##_get_type (void)                                                                  \
+{                                                                                            \
+        static volatile gsize g_define_type_id__volatile = 0;                                \
+	if (g_once_init_enter (&g_define_type_id__volatile)) {                               \
+		GType g_define_type_id =                                                     \
+		    g_type_register_static_simple (G_TYPE_INTERFACE,                         \
+		                                   g_intern_static_string (#TypeName),       \
+		                                   sizeof (TypeName##Iface),                 \
+		                                   (GClassInitFunc)type_name##_class_init,   \
+		                                   0,                                        \
+		                                   (GInstanceInitFunc)NULL,                  \
+						   (GTypeFlags) 0);                          \
+		if (TYPE_PREREQ)                                                             \
+			g_type_interface_add_prerequisite (g_define_type_id, TYPE_PREREQ);   \
+		g_once_init_leave (&g_define_type_id__volatile, g_define_type_id);           \
+	}                                                                                    \
+	return g_define_type_id__volatile;                                                   \
+}
+		
 G_END_DECLS
 
 #endif /* EV_DOCUMENT_H */