1 /* $OpenBSD: strlcat.c,v 1.13 2005/08/08 08:05:37 espie Exp $ */ 2 3 /* 4 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 /* OPENBSD ORIGINAL: lib/libc/string/strlcat.c */ 20 21 #include "openbsd-compat.h" 22 23 #if !defined(HAVE_STRLCAT) 24 25 #include <sys/types.h> 26 #include <string.h> 27 28 /* 29 * Appends src to string dst of size siz (unlike strncat, siz is the 30 * full size of dst, not space left). At most siz-1 characters 31 * will be copied. Always NUL terminates (unless siz <= strlen(dst)). 32 * Returns strlen(src) + MIN(siz, strlen(initial dst)). 33 * If retval >= siz, truncation occurred. 34 */ 35 size_t 36 strlcat(char *dst, const char *src, size_t siz) 37 { 38 char *d = dst; 39 const char *s = src; 40 size_t n = siz; 41 size_t dlen; 42 43 /* Find the end of dst and adjust bytes left but don't go past end */ 44 while (n-- != 0 && *d != '\0') 45 d++; 46 dlen = d - dst; 47 n = siz - dlen; 48 49 if (n == 0) 50 return(dlen + strlen(s)); 51 while (*s != '\0') { 52 if (n != 1) { 53 *d++ = *s; 54 n--; 55 } 56 s++; 57 } 58 *d = '\0'; 59 60 return(dlen + (s - src)); /* count does not include NUL */ 61 } 62 63 #endif /* !defined(HAVE_STRLCAT) */ 64