xref: /netbsd-src/lib/libc/stdio/fgetwln.c (revision b5677b36047b601b9addaaa494a58ceae82c2a6c)
1 /*	$NetBSD: fgetwln.c,v 1.2 2009/01/31 06:08:28 lukem Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002-2004 Tim J. Robbins.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #if defined(LIBC_SCCS) && !defined(lint)
31 #if 0
32 __FBSDID("$FreeBSD: src/lib/libc/stdio/fgetwln.c,v 1.2 2004/08/06 17:00:09 tjr Exp $");
33 #else
34 __RCSID("$NetBSD: fgetwln.c,v 1.2 2009/01/31 06:08:28 lukem Exp $");
35 #endif
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include "namespace.h"
39 #include <stdio.h>
40 #include <wchar.h>
41 #include "reentrant.h"
42 #include "local.h"
43 
44 #ifdef __weak_alias
45 __weak_alias(fgetwln,_fgetwln)
46 #endif
47 
48 wchar_t *
49 fgetwln(FILE * __restrict fp, size_t *lenp)
50 {
51 	wint_t wc;
52 	size_t len;
53 
54 	FLOCKFILE(fp);
55 	_SET_ORIENTATION(fp, 1);
56 
57 	len = 0;
58 	while ((wc = __fgetwc_unlock(fp)) != WEOF) {
59 #define	GROW	512
60 		if (len * sizeof(wchar_t) >= (size_t)fp->_lb._size &&
61 		    __slbexpand(fp, (len + GROW) * sizeof(wchar_t)))
62 			goto error;
63 		*((wchar_t *)(void *)fp->_lb._base + len++) = wc;
64 		if (wc == L'\n')
65 			break;
66 	}
67 	if (len == 0)
68 		goto error;
69 
70 	FUNLOCKFILE(fp);
71 	*lenp = len;
72 	return ((wchar_t *)(void *)fp->_lb._base);
73 
74 error:
75 	FUNLOCKFILE(fp);
76 	*lenp = 0;
77 	return (NULL);
78 }
79