freebsd-dev/lib/libc/locale/btowc.c
tjr 54a8f3fd25 Implement btowc() in terms of mbrtowc() instead of sgetrune(), and
wctob() in terms of wcrtomb() instead of sputrune(). There should be
no functional differences, but there may be a small performance hit
because we make an extra function call.

The aim here is to have as few functions as possible calling
s{get,put}rune() to make it easier to remove them in the future.
2003-08-07 07:45:35 +00:00

56 lines
1.9 KiB
C

/*-
* Copyright (c) 2002, 2003 Tim J. Robbins.
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <stdio.h>
#include <string.h>
#include <wchar.h>
wint_t
btowc(int c)
{
char cc;
wchar_t wc;
if (c == EOF)
return (WEOF);
cc = (char)c;
/*
* We expect mbrtowc() to return 0 or 1, hence the check for n > 1
* which detects error return values as well as "impossible" byte
* counts.
*
* We pass NULL as the state pointer to mbrtowc() because we don't
* support state-dependent encodings and don't want to waste time
* creating a zeroed mbstate_t that will not be used.
*/
if (mbrtowc(&wc, &cc, 1, NULL) > 1)
return (WEOF);
return (wc);
}