1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * Copyright 1997-2002 Sun Microsystems, Inc.  All rights reserved.
3*0Sstevel@tonic-gate  * Use is subject to license terms.
4*0Sstevel@tonic-gate  */
5*0Sstevel@tonic-gate 
6*0Sstevel@tonic-gate /*
7*0Sstevel@tonic-gate  * Copyright (c) 1996,1999 by Internet Software Consortium.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * Permission to use, copy, modify, and distribute this software for any
10*0Sstevel@tonic-gate  * purpose with or without fee is hereby granted, provided that the above
11*0Sstevel@tonic-gate  * copyright notice and this permission notice appear in all copies.
12*0Sstevel@tonic-gate  *
13*0Sstevel@tonic-gate  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
14*0Sstevel@tonic-gate  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
15*0Sstevel@tonic-gate  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
16*0Sstevel@tonic-gate  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
17*0Sstevel@tonic-gate  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
18*0Sstevel@tonic-gate  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
19*0Sstevel@tonic-gate  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
20*0Sstevel@tonic-gate  * SOFTWARE.
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate 
23*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint)
26*0Sstevel@tonic-gate static const char rcsid[] = "$Id: bitncmp.c,v 1.7 2001/05/29 05:49:23 marka Exp $";
27*0Sstevel@tonic-gate #endif
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate #include "port_before.h"
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #include <sys/types.h>
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate #include <string.h>
34*0Sstevel@tonic-gate 
35*0Sstevel@tonic-gate #include "port_after.h"
36*0Sstevel@tonic-gate 
37*0Sstevel@tonic-gate #include <isc/misc.h>
38*0Sstevel@tonic-gate 
39*0Sstevel@tonic-gate /*
40*0Sstevel@tonic-gate  * int
41*0Sstevel@tonic-gate  * bitncmp(l, r, n)
42*0Sstevel@tonic-gate  *	compare bit masks l and r, for n bits.
43*0Sstevel@tonic-gate  * return:
44*0Sstevel@tonic-gate  *	-1, 1, or 0 in the libc tradition.
45*0Sstevel@tonic-gate  * note:
46*0Sstevel@tonic-gate  *	network byte order assumed.  this means 192.5.5.240/28 has
47*0Sstevel@tonic-gate  *	0x11110000 in its fourth octet.
48*0Sstevel@tonic-gate  * author:
49*0Sstevel@tonic-gate  *	Paul Vixie (ISC), June 1996
50*0Sstevel@tonic-gate  */
51*0Sstevel@tonic-gate int
52*0Sstevel@tonic-gate bitncmp(const void *l, const void *r, int n) {
53*0Sstevel@tonic-gate 	u_int lb, rb;
54*0Sstevel@tonic-gate 	int x, b;
55*0Sstevel@tonic-gate 
56*0Sstevel@tonic-gate 	b = n / 8;
57*0Sstevel@tonic-gate 	x = memcmp(l, r, b);
58*0Sstevel@tonic-gate 	if (x)
59*0Sstevel@tonic-gate 		return (x);
60*0Sstevel@tonic-gate 
61*0Sstevel@tonic-gate 	lb = ((const u_char *)l)[b];
62*0Sstevel@tonic-gate 	rb = ((const u_char *)r)[b];
63*0Sstevel@tonic-gate 	for (b = n % 8; b > 0; b--) {
64*0Sstevel@tonic-gate 		if ((lb & 0x80) != (rb & 0x80)) {
65*0Sstevel@tonic-gate 			if (lb & 0x80)
66*0Sstevel@tonic-gate 				return (1);
67*0Sstevel@tonic-gate 			return (-1);
68*0Sstevel@tonic-gate 		}
69*0Sstevel@tonic-gate 		lb <<= 1;
70*0Sstevel@tonic-gate 		rb <<= 1;
71*0Sstevel@tonic-gate 	}
72*0Sstevel@tonic-gate 	return (0);
73*0Sstevel@tonic-gate }
74