contrib/libedit/src/strlcpy.c

   1 /*      $NetBSD: strlcpy.c,v 1.3 2007/06/04 18:19:27 christos Exp $     */
   2 /*      $OpenBSD: strlcpy.c,v 1.7 2003/04/12 21:56:39 millert 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 TODD C. MILLER DISCLAIMS ALL
  12  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  13  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL TODD C. MILLER BE LIABLE
  14  * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  16  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  17  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #include "config.h"
  21
  22 #if defined(LIBC_SCCS) && !defined(lint)
  23 __RCSID("$NetBSD: strlcpy.c,v 1.3 2007/06/04 18:19:27 christos Exp $");
  24 #endif /* LIBC_SCCS and not lint */
  25
  26 #include <sys/types.h>
  27 #include <assert.h>
  28 #include <string.h>
  29
  30 #ifdef _LIBC
  31 # ifdef __weak_alias
  32 __weak_alias(strlcpy, _strlcpy)
  33 # endif
  34 #endif
  35
  36 #if !HAVE_STRLCPY
  37 /*
  38  * Copy src to string dst of size siz.  At most siz-1 characters
  39  * will be copied.  Always NUL terminates (unless siz == 0).
  40  * Returns strlen(src); if retval >= siz, truncation occurred.
  41  */
  42 size_t
  43 strlcpy(char *dst, const char *src, size_t siz)
  44 {
  45         char *d = dst;
  46         const char *s = src;
  47         size_t n = siz;
  48
  49         _DIAGASSERT(dst != NULL);
  50         _DIAGASSERT(src != NULL);
  51
  52         /* Copy as many bytes as will fit */
  53         if (n != 0 && --n != 0) {
  54                 do {
  55                         if ((*d++ = *s++) == 0)
  56                                 break;
  57                 } while (--n != 0);
  58         }
  59
  60         /* Not enough room in dst, add NUL and traverse rest of src */
  61         if (n == 0) {
  62                 if (siz != 0)
  63                         *d = '\0';              /* NUL-terminate dst */
  64                 while (*s++)
  65                         ;
  66         }
  67
  68         return(s - src - 1);    /* count does not include NUL */
  69 }
  70 #endif