1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29#include "lint.h"
30#include <string.h>
31#include <sys/types.h>
32
33/*
34 * Appends src to the dstsize buffer at dst. The append will never
35 * overflow the destination buffer and the buffer will always be null
36 * terminated. Never reference beyond &dst[dstsize-1] when computing
37 * the length of the pre-existing string.
38 */
39
40size_t
41strlcat(char *dst, const char *src, size_t dstsize)
42{
43	char *df = dst;
44	size_t left = dstsize;
45	size_t l1;
46	size_t l2 = strlen(src);
47	size_t copied;
48
49	while (left-- != 0 && *df != '\0')
50		df++;
51	l1 = df - dst;
52	if (dstsize == l1)
53		return (l1 + l2);
54
55	copied = l1 + l2 >= dstsize ? dstsize - l1 - 1 : l2;
56	(void) memcpy(dst + l1, src, copied);
57	dst[l1+copied] = '\0';
58	return (l1 + l2);
59}
60