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

   1 /*
   2 FUNCTION
   3         <<wcsncpy>>---copy part of a wide-character string
   4
   5 ANSI_SYNOPSIS
   6         #include <wchar.h>
   7         wchar_t *wcsncpy(wchar_t *<[s1]>, const wchar_t *<[s2]>, size_t <[n]>);
   8
   9 TRAD_SYNOPSIS
  10         wchar_t *wcsncpy(<[s1]>, <[s2]>, <[n]>
  11         wchar_t *<[s1]>;
  12         const wchar_t *<[s2]>;
  13         size_t <[n]>;
  14
  15 DESCRIPTION
  16         The <<wcsncpy>> function copies not more than n wide-character codes
  17         (wide-character codes that follow a null wide-character code are not
  18         copied) from the array pointed to by <[s2]> to the array pointed to
  19         by <[s1]>. If copying takes place between objects that overlap, the
  20         behaviour is undefined.
  21
  22         If the array pointed to by <[s2]> is a wide-character string that is
  23         shorter than <[n]> wide-character codes, null wide-character codes are
  24         appended to the copy in the array pointed to by <[s1]>, until <[n]>
  25         wide-character codes in all are written.
  26
  27 RETURNS
  28         The <<wcsncpy>> function returns <[s1]>; no return value is reserved to
  29         indicate an error.
  30
  31 PORTABILITY
  32 <<wcsncpy>> is ISO/IEC 9899/AMD1:1995 (ISO C).
  33 No supporting OS subroutines are required.
  34 */
  35
  36 /*      $NetBSD: wcsncpy.c,v 1.1 2000/12/23 23:14:36 itojun Exp $       */
  37
  38 /*-
  39  * Copyright (c)1999 Citrus Project,
  40  * All rights reserved.
  41  *
  42  * Redistribution and use in source and binary forms, with or without
  43  * modification, are permitted provided that the following conditions
  44  * are met:
  45  * 1. Redistributions of source code must retain the above copyright
  46  *    notice, this list of conditions and the following disclaimer.
  47  * 2. Redistributions in binary form must reproduce the above copyright
  48  *    notice, this list of conditions and the following disclaimer in the
  49  *    documentation and/or other materials provided with the distribution.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  *
  63  *      citrus Id: wcsncpy.c,v 1.1 1999/12/29 21:47:45 tshiozak Exp
  64  */
  65
  66 #include <_ansi.h>
  67 #include <wchar.h>
  68
  69 wchar_t *
  70 _DEFUN (wcsncpy, (s1, s2, n),
  71         wchar_t * s1 _AND
  72         _CONST wchar_t * s2 _AND
  73         size_t n)
  74 {
  75   wchar_t *p;
  76   _CONST wchar_t *q;
  77
  78   *s1 = '\0';
  79   p = s1;
  80   q = s2;
  81   while (n && *q)
  82     {
  83       *p++ = *q++;
  84       n--;
  85     }
  86   *p = '\0';
  87
  88   return s1;
  89 }