avoid possible overflow?

[Carles Pina i Estany <carles@pina.cat>]

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Hello,

The common pattern when doing a search by bisection is something like:
+      current = min + (max - min) / 2;

Instead of the first natural idea:
-      current = (max + min) / 2;

To avoid overflows.

In gettext/gettext.c it's used in the "incorrect" way. It's not a big
problem since would happen only with .mo files with lot of strings, like
number that int represents in that architecture divided by 2 (aprox
aprox.).

See the attached file for a patch if we want to patch.

Else I would at least add a comment that we simplified because we
consider that will not happen.

Thanks,

-- 
Carles Pina i Estany
	http://pinux.info

[-- Attachment #2: gettext_overflow.patch --]
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=== modified file 'ChangeLog'
--- ChangeLog	2010-02-13 15:48:22 +0000
+++ ChangeLog	2010-02-14 00:02:48 +0000
@@ -1,3 +1,8 @@
+2010-02-13  Carles Pina i Estany  <carles@pina.cat>
+
+	* gettext/gettext.c (grub_gettext_translate): Avoids possible
+	overflow.
+
 2010-02-13  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Merge grub_ieee1275_map_physical into grub_map and rename to

=== modified file 'gettext/gettext.c'
--- gettext/gettext.c	2010-01-20 08:12:47 +0000
+++ gettext/gettext.c	2010-02-13 23:56:58 +0000
@@ -192,7 +192,7 @@ grub_gettext_translate (const char *orig
 	  grub_free (current_string);
 	  found = 1;
 	}
-      current = (max + min) / 2;
+      current = min + (max - min) / 2;
     }
 
   ret = found ? grub_gettext_gettranslation_from_position (current) : orig;