[gtk+] Don't try to modify readonly strings

[Matthias Clasen <matthiasc src gnome org>]

commit 3f1c95de8d411b956c6e51aa3bcc9baed1ab4558
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Feb 9 17:32:05 2011 -0500

    Don't try to modify readonly strings
    
    This was an oversight in the recent accel label improvement.
    When we get an untranslated string back from gettext(), it is
    not ok to replace '_' by ' ' in-place. Instead, do it while
    appending to the GString.
    https://bugzilla.gnome.org/show_bug.cgi?id=641912

 gtk/gtkaccellabel.c |   44 ++++++++++++++++++++++----------------------
 1 files changed, 22 insertions(+), 22 deletions(-)
---
diff --git a/gtk/gtkaccellabel.c b/gtk/gtkaccellabel.c
index 0b0e1bc..e48933d 100644
--- a/gtk/gtkaccellabel.c
+++ b/gtk/gtkaccellabel.c
@@ -597,30 +597,34 @@ gtk_accel_label_get_string (GtkAccelLabel *accel_label)
 }
 
 /* Underscores in key names are better displayed as spaces
- * E.g., Page_Up should be "Page Up"
+ * E.g., Page_Up should be "Page Up".
+ *
+ * Some keynames also have prefixes that are not suitable
+ * for display, e.g XF86AudioMute, so strip those out, too.
+ *
+ * This function is only called on untranslated keynames,
+ * so no need to be UTF-8 safe.
  */
 static void
-substitute_underscores (gchar *str)
+append_without_underscores (GString *s,
+                            gchar   *str)
 {
-  char *p;
+  gchar *p;
 
-  for (p = str; *p; p++)
-    if (*p == '_')
-      *p = ' ';
-}
-
-/* Some keynames have prefixes that are not suitable
- * for display, e.g XF86AudioMute
- */
-static gchar *
-strip_prefix (gchar *str)
-{
   if (g_str_has_prefix (str, "XF86"))
-    return str + 4;
+    p = str + 4;
   else if (g_str_has_prefix (str, "ISO_"))
-    return str + 4;
+    p = str + 4;
+  else
+    p = str;
 
-  return str;
+  for ( ; *p; p++)
+    {
+      if (*p == '_')
+        g_string_append_c (s, ' ');
+      else
+        g_string_append_c (s, *p);
+    }
 }
 
 /* On Mac, if the key has symbolic representation (e.g. arrow keys),
@@ -846,11 +850,7 @@ _gtk_accel_label_class_get_accelerator_label (GtkAccelLabelClass *klass,
 	      const gchar *str;
               str = g_dpgettext2 (GETTEXT_PACKAGE, "keyboard label", tmp);
 	      if (str == tmp)
-		{
-		  substitute_underscores (tmp);
-                  tmp = strip_prefix (tmp);
-		  g_string_append (gstring, tmp);
-		}
+                append_without_underscores (gstring, tmp);
 	      else
 		g_string_append (gstring, str);
 	    }