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