xref: /titanic_41/usr/src/lib/libc/port/stdio/rewind.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*	Copyright (c) 1988 AT&T	*/
30 /*	  All Rights Reserved  	*/
31 
32 
33 #include "synonyms.h"
34 #include "file64.h"
35 #include "mtlib.h"
36 #include <sys/types.h>
37 #include <stdio.h>
38 #include <unistd.h>
39 #include <synch.h>
40 #include <thread.h>
41 #include "stdiom.h"
42 #include "libc.h"
43 
44 
45 void
46 rewind(FILE *iop)
47 {
48 	rmutex_t *lk;
49 
50 	FLOCKFILE(lk, iop);
51 	_rewind_unlocked(iop);
52 	FUNLOCKFILE(lk);
53 }
54 
55 void
56 _rewind_unlocked(FILE *iop)
57 {
58 	(void) _fflush_u(iop);
59 	(void) lseek64(FILENO(iop), 0, SEEK_SET);
60 	iop->_cnt = 0;
61 	iop->_ptr = iop->_base;
62 	iop->_flag &= ~(_IOERR | _IOEOF);
63 	if (iop->_flag & _IORW)
64 		iop->_flag &= ~(_IOREAD | _IOWRT);
65 }
66