xref: /dragonfly/lib/libc/stdio/fwide.c (revision c3762235)
1 /* $NetBSD: fwide.c,v 1.3 2005/06/12 05:21:27 lukem Exp $ */
2 
3 /*-
4  * Copyright (c)2001 Citrus Project,
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $Citrus$
29  */
30 
31 #include "namespace.h"
32 #include <assert.h>
33 #include <stdio.h>
34 #include <wchar.h>
35 #include "un-namespace.h"
36 
37 #include "libc_private.h"
38 #include "local.h"
39 
40 int
41 fwide(FILE *fp, int mode)
42 {
43 	struct wchar_io_data *wcio;
44 
45 	_DIAGASSERT(fp != NULL);
46 
47 	/*
48 	 * this implementation use only -1, 0, 1
49 	 * for mode value.
50 	 * (we don't need to do this, but
51 	 *  this can make things simpler.)
52 	 */
53 	if (mode > 0)
54 		mode = 1;
55 	else if (mode < 0)
56 		mode = -1;
57 
58 	FLOCKFILE(fp);
59 	wcio = WCIO_GET(fp);
60 	if (!wcio)
61 		return 0; /* XXX */
62 
63 	if (wcio->wcio_mode == 0 && mode != 0)
64 		wcio->wcio_mode = mode;
65 	else
66 		mode = wcio->wcio_mode;
67 	FUNLOCKFILE(fp);
68 
69 	return mode;
70 }
71