diskform.h

T-kernel 的extension源代码

/*
 *----------------------------------------------------------------------
 *    T-Kernel / Standard Extension
 *
 *    Copyright (C) 2006 by Ken Sakamura. All rights reserved.
 *    T-Kernel / Standard Extension is distributed 
 *      under the T-License for T-Kernel / Standard Extension.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2006/8/11.
 *
 *----------------------------------------------------------------------
 */

/*
 *	diskform.h
 *
 *	STDFS standard disk format
 *
 *	(Note) When defining disk format structure,
 *	     prevent padding by compiler.
 *	     For this reason, UW is sometimes defined as "UH [2]".
 *
 *	< - >Bracket-enclosed section represents a definition of STDFS extension format 1.
 *	[ - ]Bracket-enclosed section represents a definition of STDFS extension format 2.
 *	      Format 1 definitions are included in format 2 definitions.
 */

#ifndef __SYS_DISKFORM_H__
#define __SYS_DISKFORM_H__

#include <basic.h>

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Maximum value of index level (that can be supported by file management)
 */
#define	MaxIndexLevel	3

/*
 * Logical block address
 */
typedef struct {
	unsigned int	cnt:8;		/* Consecutive block count */
	unsigned int	adr:24;		/* Logical block address */
} LogBlk;

/*
 * Normal index
 */
typedef struct {
	UB	always0;
	UB	rtype;			/* Record type */
	UH	stype;			/* Record subtype*/
	VB	reserved1[2];
	UH	offset;			/* Start offset */
	UW	size;			/* Record size */
	LogBlk	blk;			/* Block address */
} DfNormalIndex;

/*
 * Connection index
 */
typedef struct {
	LogBlk	blk[4];			/* Block address */
} DfConnectIndex;

/*
 * Link index
 */
typedef struct {
	UB	always00;
	UB	always80;
	UH	stype;			/* Record subtype*/
	UH	fid;			/* File ID */
	UH	atr[5];			/* Attribute data */
} DfLinkIndex;

/*
 * Record index
 */
typedef union {
	UB		type[2];
	DfNormalIndex	n;
	DfConnectIndex	c;
	DfLinkIndex	l;
} DfRecordIndex;

/*
 * Indirect index
 */
typedef struct {
	UW	nrec;			/* Number of valid records */
	UW	blk;			/* Logical block address */
} DfIndirectIndex;

/*
 * Fragment table elements
 */
typedef struct {
	UH	size;			/* Fragment size */
	UH	locate[2];		/* Position (byte address) */
} DfFragment;

typedef struct {
	UH	size;			/* Fragment size */
	UH	offset;			/* [Offset within block] */
	UW	blk;			/* [Logical block address] */
} DfFragment2;

/*
 * File location data of link file
 */
typedef struct {
	UH	fid;			/* Intended file ID */
	UH	ctime[2];		/* Generation date/time of intended file */
	VB	reserved1[4];
	VB	fsnm[40];		/* Name of intended file system */
	VB	devnm[40];		/* Device location name of intended file system */
} DfLinkFile;

/*
 * File header
 */
typedef struct {
	UW	startid;		/* File header start ID (0x54726F6E) */
	UH	ftype;			/* File type */
	UH	atype;			/* Application type */
	VB	own[28];		/* Owner name + hidden name */
	VB	grp[28];		/* Group name + hidden name */
	UH	gacclv;			/* Group access level */
	UH	pacclv;			/* General access level */
	H	nlnk;			/* Number of included links */
	H	idxlv;			/* Index level */
	W	size;			/* Total number of file bytes */
	W	nblk;			/* Total number of used logical blocks */
	W	nrec;			/* Total number of records */
	VB	reserved1[8];
	W	ltime;			/* Storage period */
	W	atime;			/* Latest date/time of access */
	W	mtime;			/* Latest date/time of update */
	W	ctime;			/* Generation date/time of file */
	VB	name[40];		/* File name */
	VB	pswd[24];		/* Password */
	W	refcnt;			/*<File reference count (>=255) >*/
	UH	ridxofs;		/*[Record index start position]*/
	VB	reserved2[8];
	UH	fid;			/* File ID */
	UW	endid;			/* File header end ID (0x82DDE96B) */
} DfFileHeader;

#define	FileHeaderTopID		0x54726F6EU	/* File header start ID */
#define	FileHeaderEndID		0x82DDE96BU	/* File header end ID */

/*
 * File header block
 *	[In Extension Format 2, the format of fragment table is DfFragment2
 *	and its size becomes variable.
 *	The start position of record index is indicated by file header ridxofs.
 *	ridxofs indicates positions on a 16-byte basis (because record index is
 *	16 bytes in size). Therefore, the number of fragment table entries is
 *	always an even number.]
 */
typedef struct {
	DfFileHeader	head;			/* File header */
	union {
		DfFragment	frag [32];	/* Fragment table */
		DfFragment2	frag2[24];	/* [Fragment table] */
		DfLinkFile	link;		/* Link file location data */
	} f;
	union {		/* Use this size when logical block size is 1KB */
		DfRecordIndex	r[40];		/* Record index */
		DfIndirectIndex	i[80];		/* Indirect index */
	} idx;
} DfFileHeaderBlock;

/*
 * Abbreviated file name
 */
typedef UW	DfShortName;

/*
 * File ID table elements
 */
typedef union {
	struct DfFileID {
#if BIGENDIAN
		unsigned int	refcnt:8;	/* File reference count */
		unsigned int	blkadr:24;	/* File start block address */
#else
		unsigned int	blkadr:24;	/* File start block address */
		unsigned int	refcnt:8;	/* File reference count */
#endif
	} s;
	UW	w;
} DfFileID;

/*
 * System header
 */
typedef struct {
	UH	fsid;				/* STDFS disk ID (0x42FE) */
	UH	diskid;				/* Disk format ID (0x6400) */
	UH	ssys;				/* System block size */
	UH	sfidt;				/* File ID table size */
	UH	sfnmt;				/* Abbreviated file name table size */
	UH	nbmp;				/* Number of bitmap bytes <number of words> */
	VB	reserved1[12];
	UH	sblk;				/* Number of logical block bytes (change H to UH) */
	UH	nfmax;				/* Maximum number of files */
	H	lang;				/* Language to use (Japanese = 0x0021) */
	H	acclv;				/* Access management level */
	W	nlb;				/* Total number of logical blocks */
	W	nflb;				/* Number of free logical blocks*/
	W	mtime;				/* Date/time of latest system block update */
	W	ctime;				/* Generation date/time of file system */
	VB	fsnm[40];			/* File system name */
	VB	devnm[40];			/* Device location name */
} DfSystemHeader;

						/* STDFS disk ID */
#define	StdfsDiskMagic	0x42FEU			/* STDFS standard format */
#define	StdfsDiskMagic_E 0x52FEU			/* STDFS extended format */
						/* Disk format ID */
#define	StdfsDiskID_A	0x6400U			/* STDFS standard format */
#define	StdfsDiskID_A2	0x8400U			/* STDFS standard format (HD) */
#define	StdfsDiskID_B	0x6401U			/* STDFS extended format 1 */
#define	StdfsDiskID_C	0x6402U			/* STDFS extended format 2 */

#ifdef __cplusplus
}
#endif
#endif /* __SYS_DISKFORM_H__ */