FreeDOS/hdr/fat.h
Bart Oldeman 7083b0a4fa On close or commit, only update those directory entry fields that have an
SFT equivalent. The rest stays unmodified on disk.


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1392 6ac86273-5f31-0410-b378-82cca8765d1b
2009-05-22 00:25:11 +00:00

156 lines
6.9 KiB
C

/****************************************************************/
/* */
/* fat.h */
/* */
/* FAT File System data structures & declarations */
/* */
/* November 26, 1991 */
/* */
/* Copyright (c) 1995 */
/* Pasquale J. Villani */
/* All Rights Reserved */
/* */
/* This file is part of DOS-C. */
/* */
/* DOS-C 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, or (at your option) any later version. */
/* */
/* DOS-C 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 DOS-C; see the file COPYING. If not, */
/* write to the Free Software Foundation, 675 Mass Ave, */
/* Cambridge, MA 02139, USA. */
/****************************************************************/
#ifdef MAIN
#ifdef VERSION_STRINGS
static BYTE *fat_hRcsId =
"$Id$";
#endif
#endif
/* FAT file system attribute bits */
#define D_NORMAL 0 /* normal */
#define D_RDONLY 0x01 /* read-only file */
#define D_HIDDEN 0x02 /* hidden */
#define D_SYSTEM 0x04 /* system */
#define D_VOLID 0x08 /* volume id */
#define D_DIR 0x10 /* subdir */
#define D_ARCHIVE 0x20 /* archive bit */
/* /// Added D_DEVICE bit. - Ron Cemer */
#define D_DEVICE 0x40 /* device bit */
#define D_LFN (D_RDONLY | D_HIDDEN | D_SYSTEM | D_VOLID)
#define D_ALL (D_RDONLY | D_HIDDEN | D_SYSTEM | D_DIR | D_ARCHIVE)
/* FAT file name constants */
#define FNAME_SIZE 8
#define FEXT_SIZE 3
/* FAT deleted flag */
#define DELETED '\x5' /* if first char, delete file */
#define EXT_DELETED '\xe5' /* external deleted flag */
/* Test for 16 bit or 12 bit FAT */
#define SIZEOF_CLST16 2
#define SIZEOF_CLST32 4
/* FAT cluster special flags */
#define FREE 0x000
#ifdef WITHFAT32
#define LONG_LAST_CLUSTER 0x0FFFFFFFUL
#define LONG_BAD 0x0FFFFFF7UL
#else
#define LONG_LAST_CLUSTER 0xFFFF
#define LONG_BAD 0xFFF7
#endif
#define MASK16 0xFFF8
#define BAD16 0xFFF7
#define MASK12 0xFF8
#define BAD12 0xFF7
/* magic constants: even though FF7 is BAD so FF6 could be a valid cluster
no., MS docs specify that FF5 is the maximal possible cluster number
for FAT12; similar for 16 and 32 */
#define FAT_MAGIC 4085
#define FAT_MAGIC16 65525U
#define FAT_MAGIC32 268435455UL
/* int ISFAT32(struct dpb FAR *dpbp);*/
#define ISFAT32(x) _ISFAT32(x)
/*
#define _ISFAT32(dpbp) (((dpbp)->dpb_size)>FAT_MAGIC16 && ((dpbp)->dpb_size)<=FAT_MAGIC32 )
*/
#define _ISFAT32(dpbp) (((dpbp)->dpb_fatsize)==0)
#define ISFAT16(dpbp) (((dpbp)->dpb_size)>FAT_MAGIC && ((dpbp)->dpb_size)<=FAT_MAGIC16 )
#define ISFAT12(dpbp) ((((dpbp)->dpb_size)-1)<FAT_MAGIC)
/* dpb_size == 0 for FAT32, hence doing -1 here */
/* FAT file system directory entry */
struct dirent {
char dir_name[FNAME_SIZE + FEXT_SIZE]; /* Filename + extension in FCB format */
UBYTE dir_attrib; /* File Attribute */
UBYTE dir_case; /* File case */
UBYTE dir_crtimems; /* Milliseconds */
UWORD dir_crtime; /* Creation time */
UWORD dir_crdate; /* Creation date */
UWORD dir_accdate; /* Last access date */
UWORD dir_start_high; /* High word of the cluster */
time dir_time; /* Time file created/updated */
date dir_date; /* Date file created/updated */
UWORD dir_start; /* Starting cluster */
/* 1st available = 2 */
ULONG dir_size; /* File size in bytes */
};
struct lfn_entry {
UBYTE lfn_id; /* Sequence number for this LFN entry */
UNICODE lfn_name0_4[5]; /* First 5 characters of LFN */
UBYTE lfn_attrib; /* LFN attribute, should be D_LFN == 0x0f */
UBYTE lfn_reserved1;
UBYTE lfn_checksum; /* Checksum for the corresponding 8.3 name */
UNICODE lfn_name5_10[6]; /* Next 6 characters of LFN */
UWORD lfn_reserved2;
UNICODE lfn_name11_12[2]; /* Last 2 characters of LFN */
};
/* */
/* filesystem sizeof(dirent) - may be different from core */
/* */
#ifdef WITHFAT32
struct dpb;
CLUSTER getdstart(struct dpb FAR *dpbp, struct dirent *dentry);
void setdstart(struct dpb FAR *dpbp, struct dirent *dentry, CLUSTER value);
BOOL checkdstart(struct dpb FAR *dpbp, struct dirent *dentry, CLUSTER value);
#else
#define getdstart(dpbp, dentry) \
((dentry)->dir_start)
#define setdstart(dpbp, dentry, value) \
(((dentry)->dir_start) = (UWORD)(value))
#define checkdstart(dpbp, dentry, value) \
(((dentry)->dir_start) == (UWORD)(value))
#endif
#define DIR_NAME 0
#define DIR_EXT FNAME_SIZE
#define DIR_ATTRIB (FNAME_SIZE+FEXT_SIZE)
#define DIR_RESERVED (FNAME_SIZE+FEXT_SIZE+1)
#define DIR_START_HIGH (FNAME_SIZE+FEXT_SIZE+9)
#define DIR_TIME (FNAME_SIZE+FEXT_SIZE+11)
#define DIR_DATE (FNAME_SIZE+FEXT_SIZE+13)
#define DIR_START (FNAME_SIZE+FEXT_SIZE+15)
#define DIR_SIZE (FNAME_SIZE+FEXT_SIZE+17)
#define DIRENT_SIZE 32