[PATCH] gettext ll_CC -> ll fallback

[Colin Watson]

This patch brings GRUB's gettext module a bit closer to the normal
semantics of GNU gettext.  For background, see:

  https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/686788
  
https://code.launchpad.net/~superm1/ubuntu/natty/grub2/chinese-support/+merge/43023

In short, languages which have ll_CC.mo rather than ll.mo don't work
right now.  Those languages are typically ones where the dialect or
writing system varies a lot between the regions where it's spoken:
zh_CN/zh_TW and pt/pt_BR are the most common cases I run into.  In some
cases it's reasonable to have a base ll.mo (Portuguese) whereas in other
cases it isn't (Chinese).  util/grub.d/00_header.in truncates $LANG at
the first '_', so it always loses the country part of the locale.

GNU gettext first tries ll_CC, then ll, which is the right way to deal
with this.  (Actually, it's a bit more complicated than that, but most
of the additional complexity is irrelevant to GRUB.)  I looked at
whether util/grub.d/00_header.in should do this, but I don't think this
should be decided at grub-mkconfig time; it would be better for GRUB's
gettext module to handle the fallback logic, just as it already looks
for compressed locale files.

2010-12-09  Colin Watson  <address@hidden>

        * grub-core/gettext/gettext.c (grub_gettext_init_ext): Factor out
        .mo/.mo.gz opening sequence to ...
        (grub_mofile_open_lang): ... here.
        (grub_gettext_init_ext): If opening ll_CC fails, try ll.
        * util/grub.d/00_header.in (grub_lang): Include country part of
        locale.

=== modified file 'grub-core/gettext/gettext.c'
--- grub-core/gettext/gettext.c 2010-09-30 19:07:51 +0000
+++ grub-core/gettext/gettext.c 2010-12-09 21:35:56 +0000
@@ -261,24 +261,16 @@ grub_mofile_open (const char *filename)
   return fd_mo;
 }
 
+/* Returning grub_file_t would be more natural, but grub_mofile_open assigns
+   to fd_mo anyway ...  */
 static void
-grub_gettext_init_ext (const char *lang)
+grub_mofile_open_lang (const char *locale_dir, const char *locale)
 {
   char *mo_file;
-  char *locale_dir;
-
-  locale_dir = grub_env_get ("locale_dir");
-  if (locale_dir == NULL)
-    {
-      grub_dprintf ("gettext", "locale_dir variable is not set up.\n");
-      return;
-    }
-
-  fd_mo = NULL;
 
   /* mo_file e.g.: /boot/grub/locale/ca.mo   */
 
-  mo_file = grub_xasprintf ("%s/%s.mo", locale_dir, lang);
+  mo_file = grub_xasprintf ("%s/%s.mo", locale_dir, locale);
   if (!mo_file)
     return;
 
@@ -295,6 +287,38 @@ grub_gettext_init_ext (const char *lang)
        return;
       fd_mo = grub_mofile_open (mo_file);
     }
+}
+
+static void
+grub_gettext_init_ext (const char *locale)
+{
+  char *locale_dir;
+
+  locale_dir = grub_env_get ("locale_dir");
+  if (locale_dir == NULL)
+    {
+      grub_dprintf ("gettext", "locale_dir variable is not set up.\n");
+      return;
+    }
+
+  fd_mo = NULL;
+
+  grub_mofile_open_lang (locale_dir, locale);
+
+  /* ll_CC didn't work, so try ll.  */
+  if (fd_mo == NULL)
+    {
+      char *lang = grub_strdup (locale);
+      char *underscore = grub_strchr (lang, '_');
+
+      if (underscore)
+       {
+         *underscore = '\0';
+         grub_mofile_open_lang (locale_dir, lang);
+       }
+
+      grub_free (lang);
+    }
 
   if (fd_mo)
     {

=== modified file 'util/grub.d/00_header.in'
--- util/grub.d/00_header.in    2010-09-18 23:15:44 +0000
+++ util/grub.d/00_header.in    2010-12-08 20:59:35 +0000
@@ -23,7 +23,7 @@ address@hidden@
 address@hidden@
 address@hidden@
 locale_dir=`echo ${GRUB_PREFIX}/locale | sed ${transform}`
-grub_lang=`echo $LANG | cut -d _ -f 1`
+grub_lang=`echo $LANG | cut -d . -f 1`
 
 . ${libdir}/grub/grub-mkconfig_lib
 

Thanks,

-- 
Colin Watson                                       address@hidden