xref: /freebsd/lib/libc/gen/rewinddir.c (revision 3416500aef140042c64bc149cb1ec6620483bc44)
1 /*-
2  * Copyright (c) 1990, 1993
3  *	The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)rewinddir.c	8.1 (Berkeley) 6/8/93";
32 #endif /* LIBC_SCCS and not lint */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include "namespace.h"
37 #include <sys/types.h>
38 #include <dirent.h>
39 #include <pthread.h>
40 #include <unistd.h>
41 #include "un-namespace.h"
42 
43 #include "libc_private.h"
44 #include "gen-private.h"
45 #include "telldir.h"
46 
47 void
48 rewinddir(DIR *dirp)
49 {
50 
51 	if (__isthreaded)
52 		_pthread_mutex_lock(&dirp->dd_lock);
53 	dirp->dd_flags &= ~__DTF_SKIPREAD; /* current contents are invalid */
54 	if (dirp->dd_flags & __DTF_READALL)
55 		_filldir(dirp, false);
56 	else {
57 		(void) lseek(dirp->dd_fd, 0, SEEK_SET);
58 		dirp->dd_seek = 0;
59 	}
60 	dirp->dd_loc = 0;
61 	_reclaim_telldir(dirp);
62 	if (__isthreaded)
63 		_pthread_mutex_unlock(&dirp->dd_lock);
64 }
65