fgetws.c revision 331722 
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: stable/11/lib/libc/stdio/fgetws.c 331722 2018-03-29 02:50:57Z eadler $");
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
45wchar_t *
46fgetws_l(wchar_t * __restrict ws, int n, FILE * __restrict fp, locale_t locale)
47{
48	int sret;
49	wchar_t *wsp, *ret;
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_CANCELSAFE(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;
114ok:
115	*wsp = L'\0';
116	ret = ws;
117end:
118	FUNLOCKFILE_CANCELSAFE();
119	return (ret);
120
121error:
122	ret = NULL;
123	goto end;
124}
125
126wchar_t *
127fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
128{
129	return fgetws_l(ws, n, fp, __get_locale());
130}
131