1 /* $OpenBSD: strlcpy.c,v 1.8 2003/06/17 21:56:24 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 #if defined(LIBC_SCCS) && !defined(lint)
20 static char *rcsid = "$OpenBSD: strlcpy.c,v 1.8 2003/06/17 21:56:24 millert Exp $";
21 #endif /* LIBC_SCCS and not lint */
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
strlcpy(char * dst,const char * src,size_t siz)32 strlcpy(char *dst, const char *src, size_t siz)
33 {
34 register char *d = dst;
35 register const char *s = src;
36 register size_t n = siz;
37
38 /* Copy as many bytes as will fit */
39 if (n != 0 && --n != 0) {
40 do {
41 if ((*d++ = *s++) == 0)
42 break;
43 } while (--n != 0);
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 }
56