xref: /freebsd/contrib/bmake/strlcpy.c (revision 724b4bfdf1306e4f2c451b6d146fe0fe0353b2c8)
1 /*	$NetBSD: strlcpy.c,v 1.3 2007/06/04 18:19:27 christos Exp $	*/
2 /*	$OpenBSD: strlcpy.c,v 1.7 2003/04/12 21:56:39 millert Exp $	*/
3 
4 /*
5  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND TODD C. MILLER DISCLAIMS ALL
12  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
13  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL TODD C. MILLER BE LIABLE
14  * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
16  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
17  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #ifdef HAVE_CONFIG_H
21 # include <config.h>
22 #endif
23 #ifndef HAVE_STRLCPY
24 
25 #include <sys/cdefs.h>
26 
27 #include <sys/types.h>
28 #include <string.h>
29 
30 /*
31  * Copy src to string dst of size siz.  At most siz-1 characters
32  * will be copied.  Always NUL terminates (unless siz == 0).
33  * Returns strlen(src); if retval >= siz, truncation occurred.
34  */
35 size_t
36 strlcpy(char *dst, const char *src, size_t siz)
37 {
38 	char *d = dst;
39 	const char *s = src;
40 	size_t n = siz;
41 
42 	if (!dst || !src)
43 		return 0;
44 
45 	/* Copy as many bytes as will fit */
46 	if (n != 0 && --n != 0) {
47 		do {
48 			if ((*d++ = *s++) == 0)
49 				break;
50 		} while (--n != 0);
51 	}
52 
53 	/* Not enough room in dst, add NUL and traverse rest of src */
54 	if (n == 0) {
55 		if (siz != 0)
56 			*d = '\0';		/* NUL-terminate dst */
57 		while (*s++)
58 			;
59 	}
60 
61 	return(s - src - 1);	/* count does not include NUL */
62 }
63 #endif
64