external/bsd/tcpdump/dist/missing/strlcpy.c

   1 /*      NetBSD: strlcpy.c,v 1.5 1999/09/20 04:39:47 lukem Exp   */
   2 /*      from OpenBSD: strlcpy.c,v 1.4 1999/05/01 18:56:41 millert Exp   */
   3
   4 /*
   5  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  20  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  21  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  22  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  23  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  24  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  25  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  26  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  27  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  28  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #ifdef HAVE_CONFIG_H
  32 #include <config.h>
  33 #endif
  34
  35 #include <tcpdump-stdinc.h>
  36
  37 #include <string.h>
  38
  39 #include "interface.h"
  40
  41 /*
  42  * Copy src to string dst of size siz.  At most siz-1 characters
  43  * will be copied.  Always NUL terminates (unless siz == 0).
  44  * Returns strlen(src); if retval >= siz, truncation occurred.
  45  */
  46 size_t
  47 strlcpy(char *dst, const char *src, size_t siz)
  48 {
  49         register char *d = dst;
  50         register const char *s = src;
  51         register size_t n = siz;
  52
  53         /* Copy as many bytes as will fit */
  54         if (n != 0 && --n != 0) {
  55                 do {
  56                         if ((*d++ = *s++) == 0)
  57                                 break;
  58                 } while (--n != 0);
  59         }
  60
  61         /* Not enough room in dst, add NUL and traverse rest of src */
  62         if (n == 0) {
  63                 if (siz != 0)
  64                         *d = '\0';              /* NUL-terminate dst */
  65                 while (*s++)
  66                         ;
  67         }
  68
  69         return(s - src - 1);    /* count does not include NUL */
  70 }