NetBSD/sys/lib/libkern/strncasecmp.c

65 lines
2.3 KiB
C

/*
* Copyright (c) 1994 Christian E. Hopps
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christian E. Hopps.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$Id: strncasecmp.c,v 1.2 1996/02/06 21:35:31 christos Exp $";
#endif /* LIBC_SCCS and not lint */
#include <string.h>
int
strncasecmp(s1, s2, n)
const char *s1;
const char *s2;
size_t n;
{
if (n == 0)
return 0;
do {
unsigned char c1 = (unsigned char) *s1++;
unsigned char c2 = (unsigned char) *s2++;
if (c1 != c2) {
if (c1 >= 'A' && c1 <= 'Z' &&
c2 >= 'a' && c2 <= 'z')
c1 += 'a' - 'A';
else if (c1 >= 'a' && c1 <= 'z' &&
c2 >= 'A' && c2 <= 'Z')
c2 += 'a' - 'A';
if (c1 != c2)
return c1 - c2;
}
if (c1 == 0)
break;
} while (--n != 0);
return 0;
}