xref: /freebsd/contrib/mandoc/compat_strlcat.c (revision 0957b409)
1 #include "config.h"
2 
3 #if HAVE_STRLCAT
4 
5 int dummy;
6 
7 #else
8 
9 /*	$OpenBSD: strlcat.c,v 1.13 2005/08/08 08:05:37 espie Exp $	*/
10 
11 /*
12  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
13  *
14  * Permission to use, copy, modify, and distribute this software for any
15  * purpose with or without fee is hereby granted, provided that the above
16  * copyright notice and this permission notice appear in all copies.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
19  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
20  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
21  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
22  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
23  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
24  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
25  */
26 
27 #include <sys/types.h>
28 #include <string.h>
29 
30 /*
31  * Appends src to string dst of size siz (unlike strncat, siz is the
32  * full size of dst, not space left).  At most siz-1 characters
33  * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
34  * Returns strlen(src) + MIN(siz, strlen(initial dst)).
35  * If retval >= siz, truncation occurred.
36  */
37 size_t
38 strlcat(char *dst, const char *src, size_t siz)
39 {
40 	char *d = dst;
41 	const char *s = src;
42 	size_t n = siz;
43 	size_t dlen;
44 
45 	/* Find the end of dst and adjust bytes left but don't go past end */
46 	while (n-- != 0 && *d != '\0')
47 		d++;
48 	dlen = d - dst;
49 	n = siz - dlen;
50 
51 	if (n == 0)
52 		return(dlen + strlen(s));
53 	while (*s != '\0') {
54 		if (n != 1) {
55 			*d++ = *s;
56 			n--;
57 		}
58 		s++;
59 	}
60 	*d = '\0';
61 
62 	return(dlen + (s - src));	/* count does not include NUL */
63 }
64 
65 #endif
66