1 /* $OpenBSD: strlcpy.c,v 1.5 2001/05/13 15:40:16 deraadt 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 #if defined(LIBC_SCCS) && !defined(lint)
31 static char *rcsid = "$OpenBSD: strlcpy.c,v 1.5 2001/05/13 15:40:16 deraadt Exp $";
32 #endif /* LIBC_SCCS and not lint */
33
34 #include <sys/types.h>
35 #include <string.h>
36
37 /*
38 * Copy src to string dst of size siz. At most siz-1 characters
39 * will be copied. Always NUL terminates (unless siz == 0).
40 * Returns strlen(src); if retval >= siz, truncation occurred.
41 */
42 size_t
strlcpy(dst,src,siz)43 strlcpy(dst, src, siz)
44 char *dst;
45 const char *src;
46 size_t siz;
47 {
48 register char *d = dst;
49 register const char *s = src;
50 register size_t n = siz;
51
52 /* Copy as many bytes as will fit */
53 if (n != 0 && --n != 0) {
54 do {
55 if ((*d++ = *s++) == 0)
56 break;
57 } while (--n != 0);
58 }
59
60 /* Not enough room in dst, add NUL and traverse rest of src */
61 if (n == 0) {
62 if (siz != 0)
63 *d = '\0'; /* NUL-terminate dst */
64 while (*s++)
65 ;
66 }
67
68 return(s - src - 1); /* count does not include NUL */
69 }
70