freebsd-dev/sys/fs/ext2fs/ext2_dir.h
Fedor Uporov 53288b712d Split the dir_index and dir_nlink features.
Do not allow to create more that EXT4_LINK_MAX links to directory in case
if the dir_nlink is not set, like it is done in the fresh e2fsprogs updates.

MFC after:      3 months
2018-08-08 12:08:46 +00:00

118 lines
3.8 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2009 Aditya Sarawgi
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 _FS_EXT2FS_EXT2_DIR_H_
#define _FS_EXT2FS_EXT2_DIR_H_
/*
* Structure of a directory entry
*/
#define EXT2FS_MAXNAMLEN 255
struct ext2fs_direct {
uint32_t e2d_ino; /* inode number of entry */
uint16_t e2d_reclen; /* length of this record */
uint16_t e2d_namlen; /* length of string in e2d_name */
char e2d_name[EXT2FS_MAXNAMLEN];/* name with length<=EXT2FS_MAXNAMLEN */
};
enum slotstatus {
NONE,
COMPACT,
FOUND
};
struct ext2fs_searchslot {
enum slotstatus slotstatus;
doff_t slotoffset; /* offset of area with free space */
int slotsize; /* size of area at slotoffset */
int slotfreespace; /* amount of space free in slot */
int slotneeded; /* sizeof the entry we are seeking */
};
/*
* The new version of the directory entry. Since EXT2 structures are
* stored in intel byte order, and the name_len field could never be
* bigger than 255 chars, it's safe to reclaim the extra byte for the
* file_type field.
*/
struct ext2fs_direct_2 {
uint32_t e2d_ino; /* inode number of entry */
uint16_t e2d_reclen; /* length of this record */
uint8_t e2d_namlen; /* length of string in e2d_name */
uint8_t e2d_type; /* file type */
char e2d_name[EXT2FS_MAXNAMLEN]; /* name with
* length<=EXT2FS_MAXNAMLEN */
};
struct ext2fs_direct_tail {
uint32_t e2dt_reserved_zero1; /* pretend to be unused */
uint16_t e2dt_rec_len; /* 12 */
uint8_t e2dt_reserved_zero2; /* zero name length */
uint8_t e2dt_reserved_ft; /* 0xDE, fake file type */
uint32_t e2dt_checksum; /* crc32c(uuid+inum+dirblock) */
};
#define EXT2_FT_DIR_CSUM 0xDE
#define EXT2_DIRENT_TAIL(data, blocksize) \
((struct ext2fs_direct_tail *)(((char *)(data)) + \
(blocksize) - sizeof(struct ext2fs_direct_tail)))
/*
* Maximal count of links to a file
*/
#define EXT4_LINK_MAX 65000
/*
* Ext2 directory file types. Only the low 3 bits are used. The
* other bits are reserved for now.
*/
#define EXT2_FT_UNKNOWN 0
#define EXT2_FT_REG_FILE 1
#define EXT2_FT_DIR 2
#define EXT2_FT_CHRDEV 3
#define EXT2_FT_BLKDEV 4
#define EXT2_FT_FIFO 5
#define EXT2_FT_SOCK 6
#define EXT2_FT_SYMLINK 7
#define EXT2_FT_MAX 8
/*
* EXT2_DIR_PAD defines the directory entries boundaries
*
* NOTE: It must be a multiple of 4
*/
#define EXT2_DIR_PAD 4
#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
~EXT2_DIR_ROUND)
#endif /* !_FS_EXT2FS_EXT2_DIR_H_ */