1 /*	$OpenBSD: strlcpy.c,v 1.11 2006/05/05 15:27:38 millert Exp $	*/
2 
3 /*
4  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 /* OPENBSD ORIGINAL: lib/libc/string/strlcpy.c */
20 
21 #include "openbsd-compat.h"
22 
23 #include <sys/types.h>
24 #include <string.h>
25 
26 /*
27  * Copy src to string dst of size siz.  At most siz-1 characters
28  * will be copied.  Always NUL terminates (unless siz == 0).
29  * Returns strlen(src); if retval >= siz, truncation occurred.
30  */
31 size_t
32 strlcpy(char *dst, const char *src, size_t siz)
33 {
34 	char *d = dst;
35 	const char *s = src;
36 	size_t n = siz;
37 
38 	/* Copy as many bytes as will fit */
39 	if (n != 0) {
40 		while (--n != 0) {
41 			if ((*d++ = *s++) == '\0')
42 				break;
43 		}
44 	}
45 
46 	/* Not enough room in dst, add NUL and traverse rest of src */
47 	if (n == 0) {
48 		if (siz != 0)
49 			*d = '\0';		/* NUL-terminate dst */
50 		while (*s++)
51 			;
52 	}
53 
54 	return(s - src - 1);	/* count does not include NUL */
55 }