1/*	$OpenBSD: fgetwc.c,v 1.4 2009/11/09 00:18:27 kurt Exp $	*/
2/* $NetBSD: fgetwc.c,v 1.3 2003/03/07 07:11:36 tshiozak Exp $ */
3
4/*-
5 * Copyright (c)2001 Citrus Project,
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $Citrus$
30 */
31
32#include <errno.h>
33#include <stdio.h>
34#include <wchar.h>
35#include "local.h"
36
37wint_t
38__fgetwc_unlock(FILE *fp)
39{
40	struct wchar_io_data *wcio;
41	mbstate_t *st;
42	wchar_t wc;
43	size_t size;
44
45	_SET_ORIENTATION(fp, 1);
46	wcio = WCIO_GET(fp);
47	if (wcio == 0) {
48		errno = ENOMEM;
49		return WEOF;
50	}
51
52	/* if there're ungetwc'ed wchars, use them */
53	if (wcio->wcio_ungetwc_inbuf) {
54		wc = wcio->wcio_ungetwc_buf[--wcio->wcio_ungetwc_inbuf];
55
56		return wc;
57	}
58
59	st = &wcio->wcio_mbstate_in;
60
61	do {
62		char c;
63		int ch = __sgetc(fp);
64
65		if (ch == EOF) {
66			return WEOF;
67		}
68
69		c = ch;
70		size = mbrtowc(&wc, &c, 1, st);
71		if (size == (size_t)-1) {
72			errno = EILSEQ;
73			return WEOF;
74		}
75	} while (size == (size_t)-2);
76
77	return wc;
78}
79
80wint_t
81fgetwc(FILE *fp)
82{
83	wint_t r;
84
85	FLOCKFILE(fp);
86	r = __fgetwc_unlock(fp);
87	FUNLOCKFILE(fp);
88
89	return (r);
90}
91