xref: /dragonfly/lib/libc/stdio/fgetwc.c (revision 9ddb8543)
1 /* $NetBSD: fgetwc.c,v 1.8 2007/04/01 18:35:53 tnozaki Exp $ */
2 /* $DragonFly: src/lib/libc/stdio/fgetwc.c,v 1.1 2005/07/25 00:37:41 joerg 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 "namespace.h"
33 #include <assert.h>
34 #include <errno.h>
35 #include <stdio.h>
36 #include <wchar.h>
37 #include "un-namespace.h"
38 
39 #include "libc_private.h"
40 #include "local.h"
41 #include "priv_stdio.h"
42 
43 wint_t
44 __fgetwc_unlock(FILE *fp)
45 {
46 	struct wchar_io_data *wcio;
47 	wchar_t wc;
48 	size_t nr;
49 
50 	_DIAGASSERT(fp != NULL);
51 
52 	_SET_ORIENTATION(fp, 1);
53 	wcio = WCIO_GET(fp);
54 	_DIAGASSERT(wcio != NULL);
55 
56 	/* if there're ungetwc'ed wchars, use them */
57 	if (wcio->wcio_ungetwc_inbuf)
58 		return(wcio->wcio_ungetwc_buf[--wcio->wcio_ungetwc_inbuf]);
59 
60 	if (fp->pub._r <= 0) {
61 restart:
62 		if (__srefill(fp) != 0)
63 			return WEOF;
64 	}
65 	nr = mbrtowc(&wc, (const char *)fp->pub._p,
66 	    (size_t)fp->pub._r, &wcio->wcio_mbstate_in);
67 	if (nr == (size_t)-1) {
68 		fp->pub._flags |= __SERR;
69 		return WEOF;
70 	} else if (nr == (size_t)-2) {
71 		fp->pub._p += fp->pub._r;
72 		fp->pub._r = 0;
73 		goto restart;
74 	}
75 	if (wc == L'\0') {
76 		while (*fp->pub._p != '\0') {
77 			++fp->pub._p;
78 			--fp->pub._r;
79 		}
80 		nr = 1;
81 	}
82 	fp->pub._p += nr;
83 	fp->pub._r -= nr;
84 
85 	return wc;
86 }
87 
88 wint_t
89 fgetwc(FILE *fp)
90 {
91 	wint_t r;
92 
93 	_DIAGASSERT(fp != NULL);
94 
95 	FLOCKFILE(fp);
96 	r = __fgetwc_unlock(fp);
97 	FUNLOCKFILE(fp);
98 
99 	return (r);
100 }
101 
102