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/*
* Copyright (c) 1996,1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "$Id: bitncmp.c,v 1.7 2001/05/29 05:49:23 marka Exp $";
#endif
#include "port_before.h"
#include <sys/types.h>
#include <string.h>
#include "port_after.h"
#include <isc/misc.h>
/*
* int
* bitncmp(l, r, n)
* compare bit masks l and r, for n bits.
* return:
* -1, 1, or 0 in the libc tradition.
* note:
* network byte order assumed. this means 192.5.5.240/28 has
* 0x11110000 in its fourth octet.
* author:
* Paul Vixie (ISC), June 1996
*/
int
bitncmp(const void *l, const void *r, int n) {
u_int lb, rb;
int x, b;
b = n / 8;
x = memcmp(l, r, b);
if (x)
return (x);
lb = ((const u_char *)l)[b];
rb = ((const u_char *)r)[b];
for (b = n % 8; b > 0; b--) {
if ((lb & 0x80) != (rb & 0x80)) {
if (lb & 0x80)
return (1);
return (-1);
}
lb <<= 1;
rb <<= 1;
}
return (0);
}
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