xref: /illumos-gate/usr/src/common/util/memcpy.c (revision 8b80e8cb6855118d46f605e91b5ed4ce83417395)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*
33  * The SunStudio compiler may generate calls to _memcpy and so we
34  * need to make sure that the correct symbol exists for these calls,
35  * whether it be libc (first case below) or the kernel (second case).
36  */
37 
38 #if !defined(_KMDB) && !defined(_BOOT) && !defined(_KERNEL)
39 
40 #include "lint.h"
41 
42 #endif /* !_KMDB && !_BOOT && !_KERNEL */
43 
44 #pragma weak _memcpy = memcpy
45 
46 #include <sys/types.h>
47 
48 #if defined(_KERNEL)
49 #include <sys/systm.h>
50 #elif !defined(_BOOT)
51 #include <stddef.h>
52 #include <string.h>
53 #endif
54 
55 #include "memcpy.h"
56 
57 /*
58  * Copy s0 to s, always copy n bytes.
59  * Return s
60  */
61 void *
62 memcpy(void *s, const void *s0, size_t n)
63 {
64 	if (n != 0) {
65 		char *s1 = s;
66 		const char *s2 = s0;
67 
68 		do {
69 			*s1++ = *s2++;
70 		} while (--n != 0);
71 	}
72 	return (s);
73 }
74