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
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 */
42size_t
43strlcpy(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