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 #include "config.h"
21
22 #if defined(LIBC_SCCS) && !defined(lint)
23 __RCSID("$NetBSD: strlcpy.c,v 1.3 2007/06/04 18:19:27 christos Exp $");
24 #endif /* LIBC_SCCS and not lint */
25
26 #include <sys/types.h>
27 #include <assert.h>
28 #include <string.h>
29
30 #ifdef _LIBC
31 # ifdef __weak_alias
__weak_alias(strlcpy,_strlcpy)32 __weak_alias(strlcpy, _strlcpy)
33 # endif
34 #endif
35
36 #if !HAVE_STRLCPY
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
43 strlcpy(char *dst, const char *src, size_t siz)
44 {
45 char *d = dst;
46 const char *s = src;
47 size_t n = siz;
48
49 _DIAGASSERT(dst != NULL);
50 _DIAGASSERT(src != NULL);
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 #endif
71