newlib/libc/string/wmemchr.c

   1 /*
   2 FUNCTION
   3         <<wmemchr>>---find a wide character in memory
   4
   5
   6 SYNOPSIS
   7         #include <wchar.h>
   8         wchar_t *wmemchr(const wchar_t *<[s]>, wchar_t <[c]>, size_t <[n]>);
   9
  10 DESCRIPTION
  11         The <<wmemchr>> function locates the first occurrence of <[c]> in the
  12         initial <[n]> wide characters of the object pointed to be <[s]>. This
  13         function is not affected by locale and all wchar_t values are treated
  14         identically.  The null wide character and wchar_t values not
  15         corresponding to valid characters are not treated specially.
  16
  17         If <[n]> is zero, <[s]> must be a valid pointer and the function
  18         behaves as if no valid occurrence of <[c]> is found.
  19
  20 RETURNS
  21         The <<wmemchr>> function returns a pointer to the located
  22         wide character, or a null pointer if the wide character does not occur
  23         in the object.
  24
  25 PORTABILITY
  26 <<wmemchr>> is ISO/IEC 9899/AMD1:1995 (ISO C).
  27
  28 No supporting OS subroutines are required.
  29 */
  30
  31 /*      $NetBSD: wmemchr.c,v 1.1 2000/12/23 23:14:37 itojun Exp $       */
  32
  33 /*-
  34  * Copyright (c)1999 Citrus Project,
  35  * All rights reserved.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  *
  58  *      citrus Id: wmemchr.c,v 1.2 2000/12/20 14:08:31 itojun Exp
  59  */
  60
  61
  62 #include <_ansi.h>
  63 #include <wchar.h>
  64
  65 wchar_t *
  66 wmemchr (const wchar_t * s,
  67         wchar_t c,
  68         size_t n)
  69 {
  70   size_t i;
  71
  72   for (i = 0; i < n; i++)
  73     {
  74       if (*s == c)
  75         {
  76           /* LINTED const castaway */
  77           return (wchar_t *) s;
  78         }
  79       s++;
  80     }
  81   return NULL;
  82 }