xref: /dragonfly/lib/libc/stdio/fgetws.c (revision ed36d35d)
1 /*-
2  * Copyright (c) 2002-2004 Tim J. Robbins.
3  * All rights reserved.
4  *
5  * Copyright (c) 2011 The FreeBSD Foundation
6  * All rights reserved.
7  * Portions of this software were developed by David Chisnall
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD: head/lib/libc/stdio/fgetws.c 227753 2011-11-20 14:45:42Z theraven $
32  */
33 
34 
35 #include "namespace.h"
36 #include <errno.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <wchar.h>
40 #include "un-namespace.h"
41 #include "libc_private.h"
42 #include "local.h"
43 #include "mblocal.h"
44 
45 wchar_t *
46 fgetws_l(wchar_t * __restrict ws, int n, FILE * __restrict fp, locale_t locale)
47 {
48 	struct wchar_io_data *wcio;
49 	mbstate_t *st;
50 	wchar_t *wsp;
51 	size_t nconv;
52 	const char *src;
53 	unsigned char *nl;
54 	FIX_LOCALE(locale);
55 	struct xlocale_ctype *l = XLOCALE_CTYPE(locale);
56 
57 	FLOCKFILE(fp);
58 	ORIENT(fp, 1);
59 	wcio = WCIO_GET(fp);
60 	if (wcio == NULL) {
61 	        errno = ENOMEM;
62 	        goto error;
63         }
64 
65 	if (n <= 0) {
66 		errno = EINVAL;
67 		goto error;
68 	}
69 
70 	wcio->wcio_ungetwc_inbuf = 0;
71 	st = &wcio->wcio_mbstate_out;
72 
73 	if (fp->pub._r <= 0 && __srefill(fp))
74 		/* EOF */
75 		goto error;
76 	wsp = ws;
77 	do {
78 		src = fp->pub._p;
79 		nl = memchr(fp->pub._p, '\n', fp->pub._r);
80 		nconv = l->__mbsnrtowcs(wsp, &src,
81 		    nl != NULL ? (nl - fp->pub._p + 1) :
82 		    fp->pub._r, n - 1, st);
83 		if (nconv == (size_t)-1)
84 			/* Conversion error */
85 			goto error;
86 		if (src == NULL) {
87 			/*
88 			 * We hit a null byte. Increment the character count,
89 			 * since mbsnrtowcs()'s return value doesn't include
90 			 * the terminating null, then resume conversion
91 			 * after the null.
92 			 */
93 			nconv++;
94 			src = memchr(fp->pub._p, '\0', fp->pub._r);
95 			src++;
96 		}
97 		fp->pub._r -= (unsigned char *)src - fp->pub._p;
98 		fp->pub._p = (unsigned char *)src;
99 		n -= nconv;
100 		wsp += nconv;
101 	} while (wsp[-1] != L'\n' && n > 1 && (fp->pub._r > 0 ||
102 	    __srefill(fp) == 0));
103 	if (wsp == ws)
104 		/* EOF */
105 		goto error;
106 	if (!l->__mbsinit(st))
107 		/* Incomplete character */
108 		goto error;
109 	*wsp = L'\0';
110 	FUNLOCKFILE(fp);
111 
112 	return (ws);
113 
114 error:
115 	FUNLOCKFILE(fp);
116 	return (NULL);
117 }
118 wchar_t *
119 fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
120 {
121 	return fgetws_l(ws, n, fp, __get_locale());
122 }
123