xref: /freebsd/lib/libc/locale/btowc.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2002, 2003 Tim J. Robbins.
5  * All rights reserved.
6  *
7  * Copyright (c) 2011 The FreeBSD Foundation
8  *
9  * Portions of this software were developed by David Chisnall
10  * under sponsorship from the FreeBSD Foundation.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <stdio.h>
35 #include <wchar.h>
36 #include "mblocal.h"
37 
38 wint_t
39 btowc_l(int c, locale_t l)
40 {
41 	static const mbstate_t initial;
42 	mbstate_t mbs = initial;
43 	char cc;
44 	wchar_t wc;
45 	FIX_LOCALE(l);
46 
47 	if (c == EOF)
48 		return (WEOF);
49 	/*
50 	 * We expect mbrtowc() to return 0 or 1, hence the check for n > 1
51 	 * which detects error return values as well as "impossible" byte
52 	 * counts.
53 	 */
54 	cc = (char)c;
55 	if (XLOCALE_CTYPE(l)->__mbrtowc(&wc, &cc, 1, &mbs) > 1)
56 		return (WEOF);
57 	return (wc);
58 }
59 wint_t
60 btowc(int c)
61 {
62 	return btowc_l(c, __get_locale());
63 }
64