1/*	$NetBSD: strlcpy.c,v 1.4 2024/11/01 21:11:37 riastradh 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 <sys/cdefs.h>
21#if defined(LIBC_SCCS) && !defined(lint)
22__RCSID("$NetBSD: strlcpy.c,v 1.4 2024/11/01 21:11:37 riastradh Exp $");
23#endif /* LIBC_SCCS and not lint */
24
25#include "netcompat.h"
26#include <sys/types.h>
27#include <assert.h>
28#include <string.h>
29/*
30 * Copy src to string dst of size siz.  At most siz-1 characters
31 * will be copied.  Always NUL terminates (unless siz == 0).
32 * Returns strlen(src); if retval >= siz, truncation occurred.
33 */
34size_t
35strlcpy(char *__restrict dst, const char *__restrict src, size_t siz)
36{
37	char *d = dst;
38	const char *s = src;
39	size_t n = siz;
40
41	_DIAGASSERT(dst != NULL);
42	_DIAGASSERT(src != NULL);
43
44	/* Copy as many bytes as will fit */
45	if (n != 0 && --n != 0) {
46		do {
47			if ((*d++ = *s++) == 0)
48				break;
49		} while (--n != 0);
50	}
51
52	/* Not enough room in dst, add NUL and traverse rest of src */
53	if (n == 0) {
54		if (siz != 0)
55			*d = '\0';		/* NUL-terminate dst */
56		while (*s++)
57			;
58	}
59
60	return(s - src - 1);	/* count does not include NUL */
61}