NetBSD/usr.bin/tn3270/general/genbsubs.c

127 lines
3.3 KiB
C

/*-
* Copyright (c) 1988 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.
*/
#ifndef lint
/*static char sccsid[] = "from: @(#)genbsubs.c 4.2 (Berkeley) 4/26/91";*/
static char rcsid[] = "$Id: genbsubs.c,v 1.2 1993/08/01 18:05:28 mycroft Exp $";
#endif /* not lint */
/* The output of bunequal is the offset of the byte which didn't match;
* if all the bytes match, then we return n.
* bunequal(s1, s2, n) */
int
bunequal(s1, s2, n)
register char *s1, *s2;
register n;
{
register int i = 0;
while (i++ < n) {
if (*s1++ != *s2++) {
break;
}
}
return(i-1);
}
/* bskip(s1, n, b) : finds the first occurrence of any byte != 'b' in the 'n'
* bytes beginning at 's1'.
*/
int
bskip(s1, n, b)
register char *s1;
register int n;
register int b;
{
register int i = 0;
while (i++ < n) {
if (*s1++ != b) {
break;
}
}
return(i-1);
}
/*
* memNSchr(const void *s, int c, size_t n, int and)
*
* Like memchr, but the comparison is '((*s)&and) == c',
* and we increment our way through s by "stride" ('s += stride').
*
* We optimize for the most used strides of +1 and -1.
*/
unsigned char *
memNSchr(s, c, n, and, stride)
char *s;
int c;
unsigned int n;
int and;
int stride;
{
register unsigned char _c, *_s, _and;
_and = and;
_c = (c&_and);
_s = (unsigned char *)s;
switch (stride) {
case 1:
while (n--) {
if (((*_s)&_and) == _c) {
return _s;
}
_s++;
}
break;
case -1:
while (n--) {
if (((*_s)&_and) == _c) {
return _s;
}
_s--;
}
break;
default:
while (n--) {
if (((*_s)&_and) == _c) {
return _s;
}
_s += stride;
}
}
return 0;
}