strlcpy.c (1786B)
1 /* $OpenBSD: strlcpy.c,v 1.12 2015/01/15 03:54:12 millert Exp $ */ 2 3 /* 4 * Copyright (c) 1998, 2015 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 #include <string.h> 20 21 #include "strlcpy.h" 22 23 #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) && \ 24 !defined(__DragonFly__) && !defined(__APPLE__) 25 26 /* 27 * Copy string src to buffer dst of size dsize. At most dsize-1 28 * chars will be copied. Always NUL terminates (unless dsize == 0). 29 * Returns strlen(src); if retval >= dsize, truncation occurred. 30 */ 31 size_t strlcpy(char* dst, const char* src, size_t dsize) { 32 const char* osrc = src; 33 size_t nleft = dsize; 34 35 /* Copy as many bytes as will fit. */ 36 if (nleft != 0) { 37 while (--nleft != 0) { 38 if ((*dst++ = *src++) == '\0') { 39 break; 40 } 41 } 42 } 43 44 /* Not enough room in dst, add NUL and traverse rest of src. */ 45 if (nleft == 0) { 46 if (dsize != 0) { 47 *dst = '\0'; /* NUL-terminate dst */ 48 } 49 while (*src++) { 50 } 51 } 52 53 return (src - osrc - 1); /* count does not include NUL */ 54 } 55 56 #endif