xref: /freebsd/contrib/openpam/lib/libpam/openpam_strlcat.c (revision 19fae0f66023a97a9b464b3beeeabb2081f575b3)
1 /*-
2  * Copyright (c) 2011-2012 Dag-Erling Smørgrav
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
14  *    products derived from this software without specific prior written
15  *    permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifdef HAVE_CONFIG_H
31 # include "config.h"
32 #endif
33 
34 #ifndef HAVE_STRLCAT
35 
36 #include <stddef.h>
37 
38 #include "openpam_strlcat.h"
39 
40 /* like strcat(3), but always NUL-terminates; returns strlen(src) */
41 size_t
42 openpam_strlcat(char *dst, const char *src, size_t size)
43 {
44 	size_t len;
45 
46 	for (len = 0; *dst && size > 1; ++len, --size)
47 		dst++;
48 	for (; *src && size > 1; ++len, --size)
49 		*dst++ = *src++;
50 	*dst = '\0';
51 	while (*src)
52 		++len, ++src;
53 	return (len);
54 }
55 
56 #endif
57