xref: /freebsd/lib/libc/stdio/fgetws.c (revision 24990dfad088db7073e30b8870d62366fb510cd3)
1 /*-
2  * Copyright (c) 2002 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("$FreeBSD$");
29 
30 #include "namespace.h"
31 #include <errno.h>
32 #include <stdio.h>
33 #include <wchar.h>
34 #include "un-namespace.h"
35 #include "libc_private.h"
36 #include "local.h"
37 
38 wchar_t *
39 fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
40 {
41 	wchar_t *wsp;
42 	wint_t wc;
43 
44 	ORIENTLOCK(fp, 1);
45 
46 	if (n <= 0)
47 		return (NULL);
48 
49 	wsp = ws;
50 	while (n-- > 1) {
51 		/* XXX Inefficient */
52 		if ((wc = fgetwc(fp)) == WEOF && errno == EILSEQ)
53 			return (NULL);
54 		if (wc == WEOF) {
55 			if (wsp == ws)
56 				/* EOF/error, no characters read yet. */
57 				return (NULL);
58 			break;
59 		}
60 		*wsp++ = (wchar_t)wc;
61 		if (wc == L'\n')
62 			break;
63 	}
64 	*wsp++ = L'\0';
65 
66 	return (ws);
67 }
68