NetBSD/gnu/dist/texinfo/lib/strcasecmp.c
2003-07-03 14:58:40 +00:00

69 lines
2.0 KiB
C

/* $NetBSD: strcasecmp.c,v 1.1.1.3 2003/07/03 14:58:58 wiz Exp $ */
/* strcasecmp.c -- case insensitive string comparator
Copyright (C) 1998, 1999 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
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#if HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef LENGTH_LIMIT
# define STRXCASECMP_FUNCTION strncasecmp
# define STRXCASECMP_DECLARE_N , size_t n
# define LENGTH_LIMIT_EXPR(Expr) Expr
#else
# define STRXCASECMP_FUNCTION strcasecmp
# define STRXCASECMP_DECLARE_N /* empty */
# define LENGTH_LIMIT_EXPR(Expr) 0
#endif
#include <stddef.h>
#include <ctype.h>
#define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch))
/* Compare {{no more than N characters of }}strings S1 and S2,
ignoring case, returning less than, equal to or
greater than zero if S1 is lexicographically less
than, equal to or greater than S2. */
int
STRXCASECMP_FUNCTION (const char *s1, const char *s2 STRXCASECMP_DECLARE_N)
{
register const unsigned char *p1 = (const unsigned char *) s1;
register const unsigned char *p2 = (const unsigned char *) s2;
unsigned char c1, c2;
if (p1 == p2 || LENGTH_LIMIT_EXPR (n == 0))
return 0;
do
{
c1 = TOLOWER (*p1);
c2 = TOLOWER (*p2);
if (LENGTH_LIMIT_EXPR (--n == 0) || c1 == '\0')
break;
++p1;
++p2;
}
while (c1 == c2);
return c1 - c2;
}