fgetws.c revision 330897 
1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2002-2004 Tim J. Robbins.
5 * All rights reserved.
6 *
7 * Copyright (c) 2011 The FreeBSD Foundation
8 * All rights reserved.
9 * Portions of this software were developed by David Chisnall
10 * under sponsorship from the FreeBSD Foundation.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD: stable/11/lib/libc/stdio/fgetws.c 330897 2018-03-14 03:19:51Z eadler $");
36
37#include "namespace.h"
38#include <errno.h>
39#include <stdio.h>
40#include <string.h>
41#include <wchar.h>
42#include "un-namespace.h"
43#include "libc_private.h"
44#include "local.h"
45#include "mblocal.h"
46
47wchar_t *
48fgetws_l(wchar_t * __restrict ws, int n, FILE * __restrict fp, locale_t locale)
49{
50	int sret;
51	wchar_t *wsp, *ret;
52	size_t nconv;
53	const char *src;
54	unsigned char *nl;
55	FIX_LOCALE(locale);
56	struct xlocale_ctype *l = XLOCALE_CTYPE(locale);
57
58	FLOCKFILE_CANCELSAFE(fp);
59	ORIENT(fp, 1);
60
61	if (n <= 0) {
62		fp->_flags |= __SERR;
63		errno = EINVAL;
64		goto error;
65	}
66
67	wsp = ws;
68	if (n == 1)
69		goto ok;
70
71	if (fp->_r <= 0 && __srefill(fp))
72		/* EOF or ferror */
73		goto error;
74
75	sret = 0;
76	do {
77		src = fp->_p;
78		nl = memchr(fp->_p, '\n', fp->_r);
79		nconv = l->__mbsnrtowcs(wsp, &src,
80		    nl != NULL ? (nl - fp->_p + 1) : fp->_r,
81		    n - 1, &fp->_mbstate);
82		if (nconv == (size_t)-1) {
83			/* Conversion error */
84			fp->_flags |= __SERR;
85			goto error;
86		}
87		if (src == NULL) {
88			/*
89			 * We hit a null byte. Increment the character count,
90			 * since mbsnrtowcs()'s return value doesn't include
91			 * the terminating null, then resume conversion
92			 * after the null.
93			 */
94			nconv++;
95			src = memchr(fp->_p, '\0', fp->_r);
96			src++;
97		}
98		fp->_r -= (unsigned char *)src - fp->_p;
99		fp->_p = (unsigned char *)src;
100		n -= nconv;
101		wsp += nconv;
102	} while ((wsp == ws || wsp[-1] != L'\n') && n > 1 && (fp->_r > 0 ||
103	    (sret = __srefill(fp)) == 0));
104	if (sret && !__sfeof(fp))
105		/* ferror */
106		goto error;
107	if (!l->__mbsinit(&fp->_mbstate)) {
108		/* Incomplete character */
109		fp->_flags |= __SERR;
110		errno = EILSEQ;
111		goto error;
112	}
113	if (wsp == ws)
114		/* EOF */
115		goto error;
116ok:
117	*wsp = L'\0';
118	ret = ws;
119end:
120	FUNLOCKFILE_CANCELSAFE();
121	return (ret);
122
123error:
124	ret = NULL;
125	goto end;
126}
127
128wchar_t *
129fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
130{
131	return fgetws_l(ws, n, fp, __get_locale());
132}
133