| 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 | |