usbloadergx/source/libntfs/mft.h
2009-12-19 14:06:57 +00:00

133 lines
4.7 KiB
C

/*
* mft.h - Exports for MFT record handling. Originated from the Linux-NTFS project.
*
* Copyright (c) 2000-2002 Anton Altaparmakov
* Copyright (c) 2004-2005 Richard Russon
* Copyright (c) 2006-2008 Szabolcs Szakacsits
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program/include file is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (in the main directory of the NTFS-3G
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _NTFS_MFT_H
#define _NTFS_MFT_H
#include "volume.h"
#include "inode.h"
#include "layout.h"
#include "logging.h"
extern int ntfs_mft_records_read(const ntfs_volume *vol, const MFT_REF mref,
const s64 count, MFT_RECORD *b);
/**
* ntfs_mft_record_read - read a record from the mft
* @vol: volume to read from
* @mref: mft record number to read
* @b: output data buffer
*
* Read the mft record specified by @mref from volume @vol into buffer @b.
* Return 0 on success or -1 on error, with errno set to the error code.
*
* The read mft record is mst deprotected and is hence ready to use. The caller
* should check the record with is_baad_record() in case mst deprotection
* failed.
*
* NOTE: @b has to be at least of size vol->mft_record_size.
*/
static __inline__ int ntfs_mft_record_read(const ntfs_volume *vol,
const MFT_REF mref, MFT_RECORD *b)
{
int ret;
ntfs_log_enter("Entering for inode %lld\n", (long long)MREF(mref));
ret = ntfs_mft_records_read(vol, mref, 1, b);
ntfs_log_leave("\n");
return ret;
}
extern int ntfs_mft_record_check(const ntfs_volume *vol, const MFT_REF mref,
MFT_RECORD *m);
extern int ntfs_file_record_read(const ntfs_volume *vol, const MFT_REF mref,
MFT_RECORD **mrec, ATTR_RECORD **attr);
extern int ntfs_mft_records_write(const ntfs_volume *vol, const MFT_REF mref,
const s64 count, MFT_RECORD *b);
/**
* ntfs_mft_record_write - write an mft record to disk
* @vol: volume to write to
* @mref: mft record number to write
* @b: data buffer containing the mft record to write
*
* Write the mft record specified by @mref from buffer @b to volume @vol.
* Return 0 on success or -1 on error, with errno set to the error code.
*
* Before the mft record is written, it is mst protected. After the write, it
* is deprotected again, thus resulting in an increase in the update sequence
* number inside the buffer @b.
*
* NOTE: @b has to be at least of size vol->mft_record_size.
*/
static __inline__ int ntfs_mft_record_write(const ntfs_volume *vol,
const MFT_REF mref, MFT_RECORD *b)
{
int ret;
ntfs_log_enter("Entering for inode %lld\n", (long long)MREF(mref));
ret = ntfs_mft_records_write(vol, mref, 1, b);
ntfs_log_leave("\n");
return ret;
}
/**
* ntfs_mft_record_get_data_size - return number of bytes used in mft record @b
* @m: mft record to get the data size of
*
* Takes the mft record @m and returns the number of bytes used in the record
* or 0 on error (i.e. @m is not a valid mft record). Zero is not a valid size
* for an mft record as it at least has to have the MFT_RECORD itself and a
* zero length attribute of type AT_END, thus making the minimum size 56 bytes.
*
* Aside: The size is independent of NTFS versions 1.x/3.x because the 8-byte
* alignment of the first attribute mask the difference in MFT_RECORD size
* between NTFS 1.x and 3.x. Also, you would expect every mft record to
* contain an update sequence array as well but that could in theory be
* non-existent (don't know if Windows' NTFS driver/chkdsk wouldn't view this
* as corruption in itself though).
*/
static __inline__ u32 ntfs_mft_record_get_data_size(const MFT_RECORD *m)
{
if (!m || !ntfs_is_mft_record(m->magic))
return 0;
/* Get the number of used bytes and return it. */
return le32_to_cpu(m->bytes_in_use);
}
extern int ntfs_mft_record_layout(const ntfs_volume *vol, const MFT_REF mref,
MFT_RECORD *mrec);
extern int ntfs_mft_record_format(const ntfs_volume *vol, const MFT_REF mref);
extern ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, ntfs_inode *base_ni);
extern int ntfs_mft_record_free(ntfs_volume *vol, ntfs_inode *ni);
extern int ntfs_mft_usn_dec(MFT_RECORD *mrec);
#endif /* defined _NTFS_MFT_H */