xref: /freebsd/lib/libc/gen/telldir.h (revision 3416500aef140042c64bc149cb1ec6620483bc44)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Copyright (c) 2000
6  * 	Daniel Eischen.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $FreeBSD$
33  */
34 
35 #ifndef _TELLDIR_H_
36 #define	_TELLDIR_H_
37 
38 #include <sys/queue.h>
39 #include <stdbool.h>
40 
41 /*
42  * One of these structures is malloced to describe the current directory
43  * position each time telldir is called. It records the current magic
44  * cookie returned by getdirentries and the offset within the buffer
45  * associated with that return value.
46  */
47 struct ddloc {
48 	LIST_ENTRY(ddloc) loc_lqe; /* entry in list */
49 	long	loc_index;	/* key associated with structure */
50 	off_t	loc_seek;	/* magic cookie returned by getdirentries */
51 	long	loc_loc;	/* offset of entry in buffer */
52 };
53 
54 /*
55  * One of these structures is malloced for each DIR to record telldir
56  * positions.
57  */
58 struct _telldir {
59 	LIST_HEAD(, ddloc) td_locq; /* list of locations */
60 	long	td_loccnt;	/* index of entry for sequential readdir's */
61 };
62 
63 bool		_filldir(DIR *, bool);
64 struct dirent	*_readdir_unlocked(DIR *, int);
65 void 		_reclaim_telldir(DIR *);
66 void 		_seekdir(DIR *, long);
67 void		_fixtelldir(DIR *dirp, long oldseek, long oldloc);
68 
69 #define	RDU_SKIP	0x0001
70 #define	RDU_SHORT	0x0002
71 
72 #endif
73