1 /* $NetBSD: strlcat.c,v 1.1.1.3 2015/01/17 16:34:18 christos Exp $ */
2
3 /*
4 * Copyright (c) 1997-2014 Erez Zadok
5 * Copyright (c) 1990 Jan-Simon Pendry
6 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
7 * Copyright (c) 1990 The Regents of the University of California.
8 * All rights reserved.
9 *
10 * This code is derived from software contributed to Berkeley by
11 * Jan-Simon Pendry at Imperial College, London.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 *
38 * File: am-utils/libamu/strlcat.c
39 *
40 */
41
42 #ifdef HAVE_CONFIG_H
43 # include <config.h>
44 #endif /* HAVE_CONFIG_H */
45 #include <am_defs.h>
46 #include <amu.h>
47
48 /*
49 * Implementation of strlcat(3) from OpenBSD/NetBSD.
50 */
51
52 /*
53 * Appends src to string dst of size siz (unlike strncat, siz is the
54 * full size of dst, not space left). At most siz-1 characters
55 * will be copied. Always NUL terminates (unless siz <= strlen(dst)).
56 * Returns strlen(src) + MIN(siz, strlen(initial dst)).
57 * If retval >= siz, truncation occurred.
58 */
59 size_t
strlcat(char * dst,const char * src,size_t siz)60 strlcat(char *dst, const char *src, size_t siz)
61 {
62 char *d = dst;
63 const char *s = src;
64 size_t n = siz;
65 size_t dlen;
66
67 /* Find the end of dst and adjust bytes left but don't go past end */
68 while (n-- != 0 && *d != '\0')
69 d++;
70 dlen = d - dst;
71 n = siz - dlen;
72
73 if (n == 0)
74 return(dlen + strlen(s));
75 while (*s != '\0') {
76 if (n != 1) {
77 *d++ = *s;
78 n--;
79 }
80 s++;
81 }
82 *d = '\0';
83
84 return(dlen + (s - src)); /* count does not include NUL */
85 }
86