freebsd-dev/lib/libc/gen/telldir.h
Konstantin Belousov 90c68c1799 Do not read away the target directory entry when encountering deleted
files after a seekdir().

The seekdir shall set the position for the next readdir operation.
When the _readdir_unlocked() encounters deleted entry, dd_loc is
already advanced. Continuing the loop leads to premature read of
the target entry.

Submitted by:	Marc Balmer <mbalmer at openbsd org>
Obtained from:	OpenBSD
MFC after:	2 weeks
2008-05-05 14:05:23 +00:00

67 lines
2.5 KiB
C

/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Copyright (c) 2000
* Daniel Eischen. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _TELLDIR_H_
#define _TELLDIR_H_
#include <sys/queue.h>
/*
* One of these structures is malloced to describe the current directory
* position each time telldir is called. It records the current magic
* cookie returned by getdirentries and the offset within the buffer
* associated with that return value.
*/
struct ddloc {
LIST_ENTRY(ddloc) loc_lqe; /* entry in list */
long loc_index; /* key associated with structure */
long loc_seek; /* magic cookie returned by getdirentries */
long loc_loc; /* offset of entry in buffer */
};
/*
* One of these structures is malloced for each DIR to record telldir
* positions.
*/
struct _telldir {
LIST_HEAD(, ddloc) td_locq; /* list of locations */
long td_loccnt; /* index of entry for sequential readdir's */
};
struct dirent *_readdir_unlocked(DIR *, int);
void _reclaim_telldir(DIR *);
void _seekdir(DIR *, long);
#endif