1 /* $OpenBSD: strlcpy.c,v 1.5 2004/08/07 00:38:33 deraadt 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 #if defined(LIBC_SCCS) && !defined(lint) 20 static char *rcsid = "$OpenBSD: strlcpy.c,v 1.5 2004/08/07 00:38:33 deraadt Exp $"; 21 #endif /* LIBC_SCCS and not lint */ 22 23 #if !defined(_KERNEL) && !defined(_STANDALONE) 24 #include <sys/types.h> 25 #include <string.h> 26 #else 27 #include <lib/libkern/libkern.h> 28 #endif 29 30 /* 31 * Copy src to string dst of size siz. At most siz-1 characters 32 * will be copied. Always NUL terminates (unless siz == 0). 33 * Returns strlen(src); if retval >= siz, truncation occurred. 34 */ 35 size_t 36 strlcpy(char *dst, const char *src, size_t siz) 37 { 38 char *d = dst; 39 const char *s = src; 40 size_t n = siz; 41 42 /* Copy as many bytes as will fit */ 43 if (n != 0 && --n != 0) { 44 do { 45 if ((*d++ = *s++) == 0) 46 break; 47 } while (--n != 0); 48 } 49 50 /* Not enough room in dst, add NUL and traverse rest of src */ 51 if (n == 0) { 52 if (siz != 0) 53 *d = '\0'; /* NUL-terminate dst */ 54 while (*s++) 55 ; 56 } 57 58 return(s - src - 1); /* count does not include NUL */ 59 } 60