67 lines
1.7 KiB
C
67 lines
1.7 KiB
C
/*
|
|
* 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);
|
|
}
|