1 /* Case-insensitive string comparison function.
2 Copyright (C) 1998, 1999, 2005, 2006, 2007, 2009 Free Software
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3, or (at your option)
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software Foundation,
17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
27 #define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch))
29 /* Compare strings S1 and S2, ignoring case, returning less than, equal to or
30 greater than zero if S1 is lexicographically less than, equal to or greater
32 Note: This function does not work with multibyte strings! */
35 strcasecmp (const char *s1, const char *s2)
37 const unsigned char *p1 = (const unsigned char *) s1;
38 const unsigned char *p2 = (const unsigned char *) s2;
57 if (UCHAR_MAX <= INT_MAX)
60 /* On machines where 'char' and 'int' are types of the same size, the
61 difference of two 'unsigned char' values - including the sign bit -
62 doesn't fit in an 'int'. */
63 return (c1 > c2 ? 1 : c1 < c2 ? -1 : 0);