wcslcat.c revision 92986 
1/*
2 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 *    derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
17 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
18 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
19 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 *	from OpenBSD: strlcat.c,v 1.3 2000/11/24 11:10:02 itojun Exp
28 */
29
30#include <sys/cdefs.h>
31#if 0
32#if defined(LIBC_SCCS) && !defined(lint)
33__RCSID("$NetBSD: wcslcat.c,v 1.1 2000/12/23 23:14:36 itojun Exp $");
34#endif /* LIBC_SCCS and not lint */
35#endif
36__FBSDID("$FreeBSD: head/lib/libc/string/wcslcat.c 92986 2002-03-22 21:53:29Z obrien $");
37
38#include <sys/types.h>
39#include <assert.h>
40#include <wchar.h>
41
42/*
43 * Appends src to string dst of size siz (unlike wcsncat, siz is the
44 * full size of dst, not space left).  At most siz-1 characters
45 * will be copied.  Always NUL terminates (unless siz == 0).
46 * Returns wcslen(initial dst) + wcslen(src); if retval >= siz,
47 * truncation occurred.
48 */
49size_t
50wcslcat(dst, src, siz)
51	wchar_t *dst;
52	const wchar_t *src;
53	size_t siz;
54{
55	wchar_t *d = dst;
56	const wchar_t *s = src;
57	size_t n = siz;
58	size_t dlen;
59
60	/* Find the end of dst and adjust bytes left but don't go past end */
61	while (*d != '\0' && n-- != 0)
62		d++;
63	dlen = d - dst;
64	n = siz - dlen;
65
66	if (n == 0)
67		return(dlen + wcslen(s));
68	while (*s != '\0') {
69		if (n != 1) {
70			*d++ = *s;
71			n--;
72		}
73		s++;
74	}
75	*d = '\0';
76
77	return(dlen + (s - src));	/* count does not include NUL */
78}
79