xref: /openbsd-src/sys/lib/libkern/bcmp.c (revision ce7e0fc6a9d74d25b78fb6ad846387717f5172b6)
1 /*	$OpenBSD: bcmp.c,v 1.5 2000/06/29 16:38:20 mickey Exp $	*/
2 
3 /*
4  * Copyright (c) 1987 Regents of the University of California.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 /*static char *sccsid = "from: @(#)bcmp.c	5.6 (Berkeley) 2/24/91";*/
38 static char *rcsid = "$OpenBSD: bcmp.c,v 1.5 2000/06/29 16:38:20 mickey Exp $";
39 #endif /* LIBC_SCCS and not lint */
40 
41 #if !defined(_KERNEL) && !defined(_STANDALONE)
42 #include <string.h>
43 #else
44 #include <lib/libkern/libkern.h>
45 #endif
46 
47 /*
48  * bcmp -- vax cmpc3 instruction
49  */
50 int
51 bcmp(b1, b2, length)
52 	const void *b1, *b2;
53 	register size_t length;
54 {
55 	register const char *p1, *p2;
56 
57 	if (length == 0)
58 		return(0);
59 	p1 = (const char *)b1;
60 	p2 = (const char *)b2;
61 	do
62 		if (*p1++ != *p2++)
63 			break;
64 	while (--length);
65 	return(length);
66 }
67