1/*-
2 * Copyright (c) 2002-2004 Tim J. Robbins.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: src/lib/libc/stdio/fgetwc.c,v 1.13 2008/04/17 22:17:53 jhb Exp $");
29
30#include "xlocale_private.h"
31
32#include "namespace.h"
33#include <errno.h>
34#include <stdio.h>
35#include <stdlib.h>
36#include <wchar.h>
37#include "un-namespace.h"
38#include "libc_private.h"
39#include "local.h"
40#include "mblocal.h"
41
42/*
43 * MT-safe version.
44 */
45wint_t
46fgetwc(FILE *fp)
47{
48	wint_t r;
49
50	FLOCKFILE(fp);
51	ORIENT(fp, 1);
52	r = __fgetwc(fp, __current_locale());
53	FUNLOCKFILE(fp);
54
55	return (r);
56}
57
58wint_t
59fgetwc_l(FILE *fp, locale_t loc)
60{
61	wint_t r;
62
63	NORMALIZE_LOCALE(loc);
64	FLOCKFILE(fp);
65	ORIENT(fp, 1);
66	r = __fgetwc(fp, loc);
67	FUNLOCKFILE(fp);
68
69	return (r);
70}
71
72/*
73 * Non-MT-safe version.
74 */
75wint_t
76__fgetwc(FILE *fp, locale_t loc)
77{
78	wchar_t wc;
79	size_t nconv;
80	struct __xlocale_st_runelocale *xrl = loc->__lc_ctype;
81	size_t (*__mbrtowc)(wchar_t * __restrict, const char * __restrict, size_t, mbstate_t * __restrict, locale_t) = xrl->__mbrtowc;
82
83	if (fp->_r <= 0 && __srefill(fp))
84		return (WEOF);
85	if (xrl->__mb_cur_max == 1) {
86		/* Fast path for single-byte encodings. */
87		wc = *fp->_p++;
88		fp->_r--;
89		return (wc);
90	}
91	do {
92		nconv = __mbrtowc(&wc, fp->_p, fp->_r, &fp->_mbstate, loc);
93		if (nconv == (size_t)-1)
94			break;
95		else if (nconv == (size_t)-2)
96			continue;
97		else if (nconv == 0) {
98			/*
99			 * Assume that the only valid representation of
100			 * the null wide character is a single null byte.
101			 */
102			fp->_p++;
103			fp->_r--;
104			return (L'\0');
105		} else {
106			fp->_p += nconv;
107			fp->_r -= nconv;
108			return (wc);
109		}
110	} while (__srefill(fp) == 0);
111	fp->_flags |= __SERR;
112	errno = EILSEQ;
113	return (WEOF);
114}
115