1 /* $NetBSD: strlcat.c,v 1.1.1.2 2014/06/13 01:48:22 christos Exp $ */ 2 /* $OpenBSD: strlcat.c,v 1.13 2005/08/08 08:05:37 espie Exp $ */ 3 4 /* 5 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 /* OPENBSD ORIGINAL: lib/libc/string/strlcat.c */ 21 #include "file.h" 22 23 #include <sys/types.h> 24 #include <string.h> 25 26 /* 27 * Appends src to string dst of size siz (unlike strncat, siz is the 28 * full size of dst, not space left). At most siz-1 characters 29 * will be copied. Always NUL terminates (unless siz <= strlen(dst)). 30 * Returns strlen(src) + MIN(siz, strlen(initial dst)). 31 * If retval >= siz, truncation occurred. 32 */ 33 size_t 34 strlcat(char *dst, const char *src, size_t siz) 35 { 36 char *d = dst; 37 const char *s = src; 38 size_t n = siz; 39 size_t dlen; 40 41 /* Find the end of dst and adjust bytes left but don't go past end */ 42 while (n-- != 0 && *d != '\0') 43 d++; 44 dlen = d - dst; 45 n = siz - dlen; 46 47 if (n == 0) 48 return(dlen + strlen(s)); 49 while (*s != '\0') { 50 if (n != 1) { 51 *d++ = *s; 52 n--; 53 } 54 s++; 55 } 56 *d = '\0'; 57 58 return(dlen + (s - src)); /* count does not include NUL */ 59 } 60