1 /* $OpenBSD: strlcpy.c,v 1.10 2005/08/08 08:05:37 espie 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 #ifdef HAVE_CONFIG_H
20 # include <config.h>
21 #endif
22
23 #include <sys/types.h>
24 #include <string.h>
25
26 size_t strlcpy(char *dst, const char *src, size_t siz);
27
28 /*
29 * Copy src to string dst of size siz. At most siz-1 characters
30 * will be copied. Always NUL terminates (unless siz == 0).
31 * Returns strlen(src); if retval >= siz, truncation occurred.
32 */
33 size_t
strlcpy(char * dst,const char * src,size_t siz)34 strlcpy(char *dst, const char *src, size_t siz)
35 {
36 char *d = dst;
37 const char *s = src;
38 size_t n = siz;
39
40 /* Copy as many bytes as will fit */
41 if (n != 0) {
42 while (--n != 0) {
43 if ((*d++ = *s++) == '\0')
44 break;
45 }
46 }
47
48 /* Not enough room in dst, add NUL and traverse rest of src */
49 if (n == 0) {
50 if (siz != 0)
51 *d = '\0'; /* NUL-terminate dst */
52 while (*s++)
53 ;
54 }
55
56 return(s - src - 1); /* count does not include NUL */
57 }
58