lib/libc/string/wcslcpy.c

   1 /*
   2  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  17  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  18  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  19  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  *
  27  * $OpenBSD: strlcpy.c,v 1.4 1999/05/01 18:56:41 millert Exp $
  28  * $NetBSD: wcslcpy.c,v 1.1 2000/12/23 23:14:36 itojun Exp $
  29  * $FreeBSD: src/lib/libc/string/wcslcpy.c,v 1.3.2.1 2001/07/11 23:48:38 obrien Exp $
  30  * $DragonFly: src/lib/libc/string/wcslcpy.c,v 1.3 2005/09/18 16:32:34 asmodai Exp $
  31  */
  32
  33 #include <sys/types.h>
  34 #include <assert.h>
  35 #include <wchar.h>
  36
  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 wcslen(src); if retval >= siz, truncation occurred.
  41  */
  42 size_t
  43 wcslcpy(wchar_t *dst, const wchar_t *src, size_t siz)
  44 {
  45         wchar_t *d = dst;
  46         const wchar_t *s = src;
  47         size_t n = siz;
  48
  49         /* Copy as many bytes as will fit */
  50         if (n != 0 && --n != 0) {
  51                 do {
  52                         if ((*d++ = *s++) == 0)
  53                                 break;
  54                 } while (--n != 0);
  55         }
  56
  57         /* Not enough room in dst, add NUL and traverse rest of src */
  58         if (n == 0) {
  59                 if (siz != 0)
  60                         *d = '\0';              /* NUL-terminate dst */
  61                 while (*s++)
  62                         ;
  63         }
  64
  65         return(s - src - 1);    /* count does not include NUL */
  66 }