newlib-cygwin/newlib/libc/string/wcsrchr.c

88 lines
2.7 KiB
C

/*
FUNCTION
<<wcsrchr>>---wide-character string scanning operation
ANSI_SYNOPSIS
#include <wchar.h>
wchar_t *wcsrchr(const wchar_t *<[s]>, wchar_t <[c]>);
TRAD_SYNOPSIS
#include <wchar.h>
wchar_t *wcsrchr(<[s]>, <[c]>
const wchar_t *<[s]>;
wchar_t <[c]>;
DESCRIPTION
The <<wcsrchr>> function locates the last occurrence of <[c]> in the
wide-character string pointed to by <[s]>. The value of <[c]> must be a
character representable as a type wchar_t and must be a wide-character
code corresponding to a valid character in the current locale.
The terminating null wide-character code is considered to be part of
the wide-character string.
RETURNS
Upon successful completion, <<wcsrchr>> returns a pointer to the
wide-character code or a null pointer if <[c]> does not occur in the
wide-character string.
PORTABILITY
<<wcsrchr>> is ISO/IEC 9899/AMD1:1995 (ISO C).
No supporting OS subroutines are required.
*/
/* $NetBSD: wcsrchr.c,v 1.1 2000/12/23 23:14:37 itojun Exp $ */
/*-
* Copyright (c)1999 Citrus Project,
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* citrus Id: wcsrchr.c,v 1.2 2000/12/21 05:07:25 itojun Exp
*/
#include <_ansi.h>
#include <stddef.h>
#include <wchar.h>
wchar_t *
_DEFUN (wcsrchr, (s, c),
_CONST wchar_t * s _AND
wchar_t c)
{
_CONST wchar_t *p;
p = s;
while (*p)
p++;
while (s <= p)
{
if (*p == c)
{
/* LINTED interface specification */
return (wchar_t *) p;
}
p--;
}
return NULL;
}