misc: Add cast in grub_strncasecmp() to drop sign when calling grub_tolower()

Note this cast was fixed in grub_strcasecmp() in commit ce41ab7aab
(* grub-core/kern/misc.c (grub_strcmp): Use unsigned comparison as per
common usage and preffered in several parts of code.), but this commit
omitted fixing it in grub_strncasecmp().

Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

diff --git a/include/grub/misc.h b/include/grub/misc.h
index 7d2b5519690755448a80fd14669c685eb5c13d47..7489685d02f344523bea98e3ba21b677f3df43e0 100644 (file)
--- a/include/grub/misc.h
+++ b/include/grub/misc.h
@@ -232,7 +232,8 @@ grub_strncasecmp (const char *s1, const char *s2, grub_size_t n)
 
   while (*s1 && *s2 && --n)
     {
-      if (grub_tolower (*s1) != grub_tolower (*s2))
+      if (grub_tolower ((grub_uint8_t) *s1)
+         != grub_tolower ((grub_uint8_t) *s2))
        break;
 
       s1++;