1199767f8SToomas Soome /* $OpenBSD: strlcat.c,v 1.15 2015/03/02 21:41:08 millert Exp $ */
2199767f8SToomas Soome
3199767f8SToomas Soome /*
4199767f8SToomas Soome * Copyright (c) 1998, 2015 Todd C. Miller <Todd.Miller@courtesan.com>
5199767f8SToomas Soome *
6199767f8SToomas Soome * Permission to use, copy, modify, and distribute this software for any
7199767f8SToomas Soome * purpose with or without fee is hereby granted, provided that the above
8199767f8SToomas Soome * copyright notice and this permission notice appear in all copies.
9199767f8SToomas Soome *
10199767f8SToomas Soome * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11199767f8SToomas Soome * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12199767f8SToomas Soome * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13199767f8SToomas Soome * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14199767f8SToomas Soome * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15199767f8SToomas Soome * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16199767f8SToomas Soome * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17199767f8SToomas Soome */
18199767f8SToomas Soome
19199767f8SToomas Soome #include <sys/cdefs.h>
20199767f8SToomas Soome __FBSDID("$FreeBSD$");
21199767f8SToomas Soome
22199767f8SToomas Soome #include <sys/types.h>
23199767f8SToomas Soome #include <string.h>
24199767f8SToomas Soome
25199767f8SToomas Soome /*
26199767f8SToomas Soome * Appends src to string dst of size dsize (unlike strncat, dsize is the
27199767f8SToomas Soome * full size of dst, not space left). At most dsize-1 characters
28199767f8SToomas Soome * will be copied. Always NUL terminates (unless dsize <= strlen(dst)).
29199767f8SToomas Soome * Returns strlen(src) + MIN(dsize, strlen(initial dst)).
30199767f8SToomas Soome * If retval >= dsize, truncation occurred.
31199767f8SToomas Soome */
32199767f8SToomas Soome size_t
strlcat(char * __restrict dst,const char * __restrict src,size_t dsize)33199767f8SToomas Soome strlcat(char * __restrict dst, const char * __restrict src, size_t dsize)
34199767f8SToomas Soome {
35199767f8SToomas Soome const char *odst = dst;
36199767f8SToomas Soome const char *osrc = src;
37199767f8SToomas Soome size_t n = dsize;
38199767f8SToomas Soome size_t dlen;
39199767f8SToomas Soome
40199767f8SToomas Soome /* Find the end of dst and adjust bytes left but don't go past end. */
41199767f8SToomas Soome while (n-- != 0 && *dst != '\0')
42199767f8SToomas Soome dst++;
43199767f8SToomas Soome dlen = dst - odst;
44199767f8SToomas Soome n = dsize - dlen;
45199767f8SToomas Soome
46199767f8SToomas Soome if (n-- == 0)
47199767f8SToomas Soome return(dlen + strlen(src));
48199767f8SToomas Soome while (*src != '\0') {
49199767f8SToomas Soome if (n != 0) {
50199767f8SToomas Soome *dst++ = *src;
51199767f8SToomas Soome n--;
52199767f8SToomas Soome }
53199767f8SToomas Soome src++;
54199767f8SToomas Soome }
55199767f8SToomas Soome *dst = '\0';
56199767f8SToomas Soome
57199767f8SToomas Soome return(dlen + (src - osrc)); /* count does not include NUL */
58199767f8SToomas Soome }
59