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