1 /*	$OpenBSD: strlcpy.c,v 1.2 1998/11/06 04:33:16 wvdputte Exp $	*/
2 
3 /*
4  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
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. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
19  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
20  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
21  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
27  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 #include <string.h>
32 
33 size_t strlcpy(char *, const char *, size_t);
34 
35 /*
36  * Copy src to string dst of size siz.  At most siz-1 characters
37  * will be copied.  Always NUL terminates (unless siz == 0).
38  * Returns strlen(src); if retval >= siz, truncation occurred.
39  */
strlcpy(dst,src,siz)40 size_t strlcpy(dst, src, siz)
41 	char *dst;
42 	const char *src;
43 	size_t siz;
44 {
45 	register char *d = dst;
46 	register const char *s = src;
47 	register size_t n = siz;
48 
49 	if (n == 0)
50 		return(strlen(s));
51 	while (*s != '\0') {
52 		if (n != 1) {
53 			*d++ = *s;
54 			n--;
55 		}
56 		s++;
57 	}
58 	*d = '\0';
59 
60 	return(s - src);	/* count does not include NUL */
61 }
62