xref: /freebsd/lib/libc/gen/telldir.h (revision 718cf2ccb9956613756ab15d7a0e28f2c8e91cab)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Copyright (c) 2000
8  * 	Daniel Eischen.  All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $FreeBSD$
35  */
36 
37 #ifndef _TELLDIR_H_
38 #define	_TELLDIR_H_
39 
40 #include <sys/queue.h>
41 #include <stdbool.h>
42 
43 /*
44  * One of these structures is malloced to describe the current directory
45  * position each time telldir is called. It records the current magic
46  * cookie returned by getdirentries and the offset within the buffer
47  * associated with that return value.
48  */
49 struct ddloc {
50 	LIST_ENTRY(ddloc) loc_lqe; /* entry in list */
51 	long	loc_index;	/* key associated with structure */
52 	off_t	loc_seek;	/* magic cookie returned by getdirentries */
53 	long	loc_loc;	/* offset of entry in buffer */
54 };
55 
56 /*
57  * One of these structures is malloced for each DIR to record telldir
58  * positions.
59  */
60 struct _telldir {
61 	LIST_HEAD(, ddloc) td_locq; /* list of locations */
62 	long	td_loccnt;	/* index of entry for sequential readdir's */
63 };
64 
65 bool		_filldir(DIR *, bool);
66 struct dirent	*_readdir_unlocked(DIR *, int);
67 void 		_reclaim_telldir(DIR *);
68 void 		_seekdir(DIR *, long);
69 void		_fixtelldir(DIR *dirp, long oldseek, long oldloc);
70 
71 #define	RDU_SKIP	0x0001
72 #define	RDU_SHORT	0x0002
73 
74 #endif
75