gobject: Add a boxed type for string references

Pretty simple boxed wrapper using the GRef API directly.

https://bugzilla.gnome.org/show_bug.cgi?id=622721

gobject/gboxed.c

@@ -184,6 +184,36 @@ g_strv_get_type (void)
   return g_define_type_id__volatile;
 }
 
+/* This one can't use G_DEFINE_BOXED_TYPE (GStringRef, g_string_ref, g_string_ref, g_string_unref)
+ *
+ * We also use the g_ref_pointer_* API directly because the g_string_ref/unref
+ * functions are inlined and hidden by a macro, so we can't use them as function
+ * pointers.
+ */
+GType
+g_string_ref_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_boxed_type_register_static (g_intern_static_string ("GStringRef"),
+                                      (GBoxedCopyFunc) g_ref_pointer_acquire,
+                                      (GBoxedFreeFunc) g_ref_pointer_release);
+
+      g_once_init_leave (&g_define_type_id__volatile, g_define_type_id);
+    }
+
+  return g_define_type_id__volatile;
+}
+
+/**
+ * g_variant_get_gtype:
+ *
+ * Since: 2.24
+ * Deprecated: 2.26
+ */
 GType
 g_variant_get_gtype (void)
 {

gobject/glib-types.h

@@ -288,6 +288,15 @@ typedef gsize GType;
  */
 #define G_TYPE_CHECKSUM (g_checksum_get_type ())
 
+/**
+ * G_TYPE_STRING_REF:
+ *
+ * The #GType for a boxed type holding a string reference.
+ *
+ * Since: 2.44
+ */
+#define G_TYPE_STRING_REF (g_string_ref_get_type ())
+
 GLIB_AVAILABLE_IN_ALL
 GType   g_date_get_type            (void) G_GNUC_CONST;
 GLIB_AVAILABLE_IN_ALL
@@ -342,6 +351,8 @@ GLIB_AVAILABLE_IN_2_36
 GType   g_markup_parse_context_get_type (void) G_GNUC_CONST;
 GLIB_AVAILABLE_IN_2_40
 GType   g_mapped_file_get_type (void) G_GNUC_CONST;
+GLIB_AVAILABLE_IN_2_44
+GType   g_string_ref_get_type      (void) G_GNUC_CONST;
 
 GLIB_DEPRECATED_FOR('G_TYPE_VARIANT')
 GType   g_variant_get_gtype        (void) G_GNUC_CONST;
@@ -353,6 +364,15 @@ GType   g_variant_get_gtype        (void) G_GNUC_CONST;
  */
 typedef gchar** GStrv;
 
+/**
+ * GStringRef:
+ *
+ * A C representable type for #G_TYPE_STRING_REF.
+ *
+ * Since: 2.44
+ */
+typedef char* GStringRef;
+
 G_END_DECLS
 
 #endif  /* __GLIB_TYPES_H__ */

gobject/gobject-autocleanups.h

@@ -22,5 +22,6 @@
 #endif
 
 G_DEFINE_AUTO_CLEANUP_FREE_FUNC(GStrv, g_strfreev, NULL)
+G_DEFINE_AUTO_CLEANUP_FREE_FUNC(GStringRef, g_string_unref, NULL)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GObject, g_object_unref)
 G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(GValue, g_value_unset)

gobject/gvaluetypes.c

@@ -1397,6 +1397,12 @@ g_strdup_value_contents (const GValue *value)
           g_string_append (tmp, "]");
           contents = g_string_free (tmp, FALSE);
         }
+      else if (G_VALUE_HOLDS (value, G_TYPE_STRING_REF))
+        {
+          GStringRef str = g_value_get_boxed (value);
+
+	  contents = g_strdup_printf ("\"%s\"", str);
+        }
       else if (G_VALUE_HOLDS_BOXED (value))
 	contents = g_strdup_printf ("((%s*) %p)", g_type_name (G_VALUE_TYPE (value)), p);
       else if (G_VALUE_HOLDS_POINTER (value))