strlcpy.c (1737B)
1 /* 2 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com> 3 * 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND TODD C. MILLER DISCLAIMS ALL 9 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES 10 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL TODD C. MILLER BE LIABLE 11 * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 13 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 14 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 15 */ 16 17 #ifdef HAVE_DIX_CONFIG_H 18 #include <dix-config.h> 19 #endif 20 21 #include <sys/types.h> 22 #include <string.h> 23 #include "os.h" 24 25 #ifndef HAVE_STRLCPY 26 /* 27 * Copy src to string dst of size siz. At most siz-1 characters 28 * will be copied. Always NUL terminates (unless siz == 0). 29 * Returns strlen(src); if retval >= siz, truncation occurred. 30 */ 31 size_t 32 strlcpy(char *dst, const char *src, size_t siz) 33 { 34 register char *d = dst; 35 register const char *s = src; 36 register size_t n = siz; 37 38 /* Copy as many bytes as will fit */ 39 if (n != 0 && --n != 0) { 40 do { 41 if ((*d++ = *s++) == 0) 42 break; 43 } while (--n != 0); 44 } 45 46 /* Not enough room in dst, add NUL and traverse rest of src */ 47 if (n == 0) { 48 if (siz != 0) 49 *d = '\0'; /* NUL-terminate dst */ 50 while (*s++); 51 } 52 53 return s - src - 1; /* count does not include NUL */ 54 } 55 #endif