xref: /titanic_41/usr/src/lib/libc/port/gen/stpncpy.c (revision 49d3bc91e27cd871b950d56c01398fa2f2e12ab4)
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 (c) 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 /*	Copyright (c) 1988 AT&T	*/
27 /*	  All Rights Reserved  	*/
28 
29 #include "lint.h"
30 #include <string.h>
31 #include <sys/types.h>
32 
33 /*
34  * Copy s2 to s1, truncating or null-padding to always copy n bytes
35  * return a pointer to the terminating null byte in s1, or,
36  * if s1 is not null-terminated, s1 + n.
37  */
38 char *
39 stpncpy(char *_RESTRICT_KYWD s1, const char *_RESTRICT_KYWD s2, size_t n)
40 {
41 	size_t len = strnlen(s2, n);
42 
43 	(void) strncpy(s1, s2, n);
44 
45 	return ((len < n) ? s1 + len : s1 + n);
46 }
47