xref: /freebsd/lib/libc/stdio/fgetws.c (revision 3fc36ee018bb836bd1796067cf4ef8683f166ebc)
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 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
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 	int sret;
49 	wchar_t *wsp;
50 	size_t nconv;
51 	const char *src;
52 	unsigned char *nl;
53 	FIX_LOCALE(locale);
54 	struct xlocale_ctype *l = XLOCALE_CTYPE(locale);
55 
56 	FLOCKFILE(fp);
57 	ORIENT(fp, 1);
58 
59 	if (n <= 0) {
60 		fp->_flags |= __SERR;
61 		errno = EINVAL;
62 		goto error;
63 	}
64 
65 	wsp = ws;
66 	if (n == 1)
67 		goto ok;
68 
69 	if (fp->_r <= 0 && __srefill(fp))
70 		/* EOF or ferror */
71 		goto error;
72 
73 	sret = 0;
74 	do {
75 		src = fp->_p;
76 		nl = memchr(fp->_p, '\n', fp->_r);
77 		nconv = l->__mbsnrtowcs(wsp, &src,
78 		    nl != NULL ? (nl - fp->_p + 1) : fp->_r,
79 		    n - 1, &fp->_mbstate);
80 		if (nconv == (size_t)-1) {
81 			/* Conversion error */
82 			fp->_flags |= __SERR;
83 			goto error;
84 		}
85 		if (src == NULL) {
86 			/*
87 			 * We hit a null byte. Increment the character count,
88 			 * since mbsnrtowcs()'s return value doesn't include
89 			 * the terminating null, then resume conversion
90 			 * after the null.
91 			 */
92 			nconv++;
93 			src = memchr(fp->_p, '\0', fp->_r);
94 			src++;
95 		}
96 		fp->_r -= (unsigned char *)src - fp->_p;
97 		fp->_p = (unsigned char *)src;
98 		n -= nconv;
99 		wsp += nconv;
100 	} while ((wsp == ws || wsp[-1] != L'\n') && n > 1 && (fp->_r > 0 ||
101 	    (sret = __srefill(fp)) == 0));
102 	if (sret && !__sfeof(fp))
103 		/* ferror */
104 		goto error;
105 	if (!l->__mbsinit(&fp->_mbstate)) {
106 		/* Incomplete character */
107 		fp->_flags |= __SERR;
108 		errno = EILSEQ;
109 		goto error;
110 	}
111 	if (wsp == ws)
112 		/* EOF */
113 		goto error;
114 ok:
115 	*wsp = L'\0';
116 	FUNLOCKFILE(fp);
117 	return (ws);
118 
119 error:
120 	FUNLOCKFILE(fp);
121 	return (NULL);
122 }
123 
124 wchar_t *
125 fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
126 {
127 	return fgetws_l(ws, n, fp, __get_locale());
128 }
129