freebsd-src/sys/libkern/strcasecmp.c
Pawel Jakub Dawidek 57169160b0 Ha! This is a very interesting bug.
I copied strcasecmp() from userland to the kernel and it didn't worked!
I started to debug the problem and I find out that this line:

	while (tolower(*us1) == tolower(*us2++)) {

was adding _3_ bytes to 'us2' pointer. Am I loosing my minds here?!...
No, in-kernel tolower() is a macro which uses its argument three times.
Bad tolower(9), no cookie.
2005-08-08 19:38:00 +00:00

72 lines
2.5 KiB
C

/*
* Copyright (c) 1987, 1993
* The Regents of the University of California. 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 the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/ctype.h>
#include <sys/libkern.h>
int
strcasecmp(const char *s1, const char *s2)
{
const u_char *us1 = (const u_char *)s1, *us2 = (const u_char *)s2;
while (tolower(*us1) == tolower(*us2)) {
if (*us1++ == '\0')
return (0);
us2++;
}
return (tolower(*us1) - tolower(*us2));
}
int
strncasecmp(const char *s1, const char *s2, size_t n)
{
if (n != 0) {
const u_char *us1 = (const u_char *)s1;
const u_char *us2 = (const u_char *)s2;
do {
if (tolower(*us1) != tolower(*us2))
return (tolower(*us1) - tolower(*us2));
if (*us1++ == '\0')
break;
us2++;
} while (--n != 0);
}
return (0);
}