fgetws.c revision 136092 
1/*-
2 * Copyright (c) 2002-2004 Tim J. Robbins.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/lib/libc/stdio/fgetws.c 136092 2004-10-03 15:48:32Z stefanf $");
29
30#include "namespace.h"
31#include <errno.h>
32#include <stdio.h>
33#include <string.h>
34#include <wchar.h>
35#include "un-namespace.h"
36#include "libc_private.h"
37#include "local.h"
38#include "mblocal.h"
39
40wchar_t *
41fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
42{
43	wchar_t *wsp;
44	size_t nconv;
45	const char *src;
46	unsigned char *nl;
47
48	FLOCKFILE(fp);
49	ORIENT(fp, 1);
50
51	if (n <= 0) {
52		errno = EINVAL;
53		goto error;
54	}
55
56	if (fp->_r <= 0 && __srefill(fp))
57		/* EOF */
58		goto error;
59	wsp = ws;
60	do {
61		src = fp->_p;
62		nl = memchr(fp->_p, '\n', fp->_r);
63		nconv = __mbsnrtowcs(wsp, &src,
64		    nl != NULL ? (nl - fp->_p + 1) : fp->_r,
65		    n - 1, &fp->_extra->mbstate);
66		if (nconv == (size_t)-1)
67			/* Conversion error */
68			goto error;
69		if (src == NULL) {
70			/*
71			 * We hit a null byte. Increment the character count,
72			 * since mbsnrtowcs()'s return value doesn't include
73			 * the terminating null, then resume conversion
74			 * after the null.
75			 */
76			nconv++;
77			src = memchr(fp->_p, '\0', fp->_r);
78			src++;
79		}
80		fp->_r -= (unsigned char *)src - fp->_p;
81		fp->_p = (unsigned char *)src;
82		n -= nconv;
83		wsp += nconv;
84	} while (wsp[-1] != L'\n' && n > 1 && (fp->_r > 0 ||
85	    __srefill(fp) == 0));
86	if (wsp == ws)
87		/* EOF */
88		goto error;
89	if (!__mbsinit(&fp->_extra->mbstate))
90		/* Incomplete character */
91		goto error;
92	*wsp++ = L'\0';
93	FUNLOCKFILE(fp);
94
95	return (ws);
96
97error:
98	FUNLOCKFILE(fp);
99	return (NULL);
100}
101