diff options
author | Bruno Haible <bruno@clisp.org> | 2005-10-11 12:47:44 +0000 |
---|---|---|
committer | Bruno Haible <bruno@clisp.org> | 2005-10-11 12:47:44 +0000 |
commit | 47b3dd4ed61927c7dfc9ba870d9c0fa763ac57d8 (patch) | |
tree | 06e7d7a1aebcdacc7fd947d8501c05b21e632150 /lib/strncasecmp.c | |
parent | 3eef42323e03d43424480e77232cd118a035de62 (diff) | |
download | gnulib-47b3dd4ed61927c7dfc9ba870d9c0fa763ac57d8.tar.gz |
Avoid integer overflow on exotic platforms.
Diffstat (limited to 'lib/strncasecmp.c')
-rw-r--r-- | lib/strncasecmp.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/lib/strncasecmp.c b/lib/strncasecmp.c index 72ead013be..0209c39ea0 100644 --- a/lib/strncasecmp.c +++ b/lib/strncasecmp.c @@ -1,5 +1,5 @@ /* strncasecmp.c -- case insensitive string comparator - Copyright (C) 1998, 1999 Free Software Foundation, Inc. + Copyright (C) 1998, 1999, 2005 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -23,6 +23,7 @@ #include "strcase.h" #include <ctype.h> +#include <limits.h> #define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch)) @@ -54,5 +55,11 @@ strncasecmp (const char *s1, const char *s2, size_t n) } while (c1 == c2); - return c1 - c2; + if (UCHAR_MAX <= INT_MAX) + return c1 - c2; + else + /* On machines where 'char' and 'int' are types of the same size, the + difference of two 'unsigned char' values - including the sign bit - + doesn't fit in an 'int'. */ + return (c1 > c2 ? 1 : c1 < c2 ? -1 : 0); } |