toolchain/gcc/newlib/libc/string/wcslcpy.c

   1 /*
   2 FUNCTION
   3         <<wcslcpy>>---copy a wide-character string to specified length
   4
   5 ANSI_SYNOPSIS
   6         #include <wchar.h>
   7         size_t wcslcpy(wchar_t *<[dst]>, const wchar_t *<[src]>, size_t <[siz]>);
   8
   9 TRAD_SYNOPSIS
  10         #include <wchar.h>
  11         size_t wcslcpy(<[dst]>, <[src]>, <[siz]>)
  12         wchar_t *<[dst]>;
  13         const wchar_t *<[src]>;
  14         size_t <[siz]>;
  15
  16 DESCRIPTION
  17         <<wcslcpy>> copies wide-characters from <[src]> to <[dst]>
  18         such that up to <[siz]> - 1 characters are copied.  A
  19         terminating null is appended to the result, unless <[siz]>
  20         is zero.
  21
  22 RETURNS
  23         <<wcslcpy>> returns the number of wide-characters in <[src]>,
  24         not including the terminating null wide-character.  If the
  25         return value is greater than or equal to <[siz]>, then
  26         not all wide-characters were copied from <[src]> and truncation
  27         occurred.
  28
  29 PORTABILITY
  30 No supporting OS subroutines are required.
  31 */
  32
  33 /*      $NetBSD: wcslcpy.c,v 1.1 2000/12/23 23:14:36 itojun Exp $       */
  34 /*      from OpenBSD: strlcpy.c,v 1.4 1999/05/01 18:56:41 millert Exp   */
  35
  36 /*
  37  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
  38  * All rights reserved.
  39  *
  40  * Redistribution and use in source and binary forms, with or without
  41  * modification, are permitted provided that the following conditions
  42  * are met:
  43  * 1. Redistributions of source code must retain the above copyright
  44  *    notice, this list of conditions and the following disclaimer.
  45  * 2. Redistributions in binary form must reproduce the above copyright
  46  *    notice, this list of conditions and the following disclaimer in the
  47  *    documentation and/or other materials provided with the distribution.
  48  * 3. The name of the author may not be used to endorse or promote products
  49  *    derived from this software without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  52  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  53  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  54  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  55  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  56  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  57  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  58  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  59  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  60  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  */
  62
  63 #include <_ansi.h>
  64 #include <wchar.h>
  65
  66 /*
  67  * Copy src to string dst of size siz.  At most siz-1 characters
  68  * will be copied.  Always NUL terminates (unless siz == 0).
  69  * Returns wcslen(src); if retval >= siz, truncation occurred.
  70  */
  71 size_t
  72 _DEFUN (wcslcpy, (dst, src, siz),
  73         wchar_t * dst _AND
  74         _CONST wchar_t * src _AND
  75         size_t siz)
  76 {
  77   wchar_t *d = dst;
  78   _CONST wchar_t *s = src;
  79   size_t n = siz;
  80
  81   /* Copy as many bytes as will fit */
  82   if (n != 0 && --n != 0)
  83     {
  84       do
  85         {
  86           if ((*d++ = *s++) == 0)
  87             break;
  88         }
  89       while (--n != 0);
  90     }
  91
  92   /* Not enough room in dst, add NUL and traverse rest of src */
  93   if (n == 0)
  94     {
  95       if (siz != 0)
  96         *d = '\0';              /* NUL-terminate dst */
  97       while (*s++)
  98         ;
  99     }
 100
 101   return (s - src - 1);         /* count does not include NUL */
 102 }