xref: /freebsd/lib/libc/stdio/fgetwln.c (revision f0a75d274af375d15b97b830966b99a02b7db911)
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("$FreeBSD$");
29 
30 #include "namespace.h"
31 #include <stdio.h>
32 #include <wchar.h>
33 #include "un-namespace.h"
34 #include "libc_private.h"
35 #include "local.h"
36 
37 wchar_t *
38 fgetwln(FILE * __restrict fp, size_t *lenp)
39 {
40 	wint_t wc;
41 	size_t len;
42 
43 	FLOCKFILE(fp);
44 	ORIENT(fp, 1);
45 
46 	len = 0;
47 	while ((wc = __fgetwc(fp)) != WEOF) {
48 #define	GROW	512
49 		if (len * sizeof(wchar_t) >= fp->_lb._size &&
50 		    __slbexpand(fp, (len + GROW) * sizeof(wchar_t)))
51 			goto error;
52 		*((wchar_t *)fp->_lb._base + len++) = wc;
53 		if (wc == L'\n')
54 			break;
55 	}
56 	if (len == 0)
57 		goto error;
58 
59 	FUNLOCKFILE(fp);
60 	*lenp = len;
61 	return ((wchar_t *)fp->_lb._base);
62 
63 error:
64 	FUNLOCKFILE(fp);
65 	*lenp = 0;
66 	return (NULL);
67 }
68