ramdisk.h

内存驱动器的源代码ramdisk,很有用的

//=============================================================================
//
// Compuware Corporation
// NuMega Lab
// 9 Townsend West
// Nashua, NH 03060  USA
//
// Copyright (c) 1998 Compuware Corporation. All Rights Reserved.
// Unpublished - rights reserved under the Copyright laws of the
// United States.
//
//=============================================================================

// RAMDISK.H - include file for the Registry File System driver
// Copyright (c) 1996 Compuware Corporation

#include <vtoolsc.h>
#include <ddb.h>

/////////////////////////////////////////////////////////////////////
// Constants

// Constants required by the VtoolsD framework 
#define RAMDISK_Major		1
#define RAMDISK_Minor		0
#define RAMDISK_DeviceID	UNDEFINED_DEVICE_ID
#define RAMDISK_Init_Order	UNDEFINED_INIT_ORDER

// Constants for the Device Registration Packet
#define RAMDISK_NAME	"RAMDISK         "
#define RAMDISK_REV 	1
#define RAMDISK_FEATURE	0
#define RAMDISK_IFR	0
#define DISKSIZE	3*1024*1024
// Size of the buffer used to read in value data
#define READBUFSIZE 512

// Macro to define the byte offset from the start of an IOP to the 
// start of the embedded IOR. Assumes no IOP extension.
//#define IORDELTA ((ULONG)(&((IOP*)0)->IOP_ior))

// Special value to denote the real root of the Registry, i.e., the
// implied root below the six predefined roots.
//#define REGISTRY_ROOT	0xffffffff

/*
// Macros for debugging
#ifdef DEBUG
// Display the string s and variable t
#define fsdtrace(s, t) dprintf("%s: pir=%x\n", s, t)
// Force a heap walk (use in conjunction with .m? command in debugger)
#define ForceHeapWalk(s) free(malloc(1));dprintf(s);DebugBreak()
#else  // non-debug versions are empty
#define fsdtrace(s, t) 
#define ForceHeapWalk(s) 
#endif
*/
/////////////////////////////////////////////////////////////////////
// Types
typedef struct tagBPB
	{						// BIOS parameter block
	WORD secsize;			// 00 sector size
	BYTE clustsize;			// 02 cluster size (in sectors)
	WORD numrsv;			// 03 # reserved sectors
	BYTE numfat;			// 05 # FATs
	WORD numfiles;			// 06 # entries in root directory
	WORD numsectors;		// 08 # sectors on disk
	BYTE media;				// 0A media descriptor
	WORD fatsectors;		// 0B # sectors in each FAT
	} BPB, *PBPB;			// BIOS parameter block [0D]

typedef struct tagPARTITION
	{						// partition record
	BYTE indicator;			// 00 boot indicator (80 = active partition)
	BYTE starthead;			// 01 start head
	BYTE startsec;			// 02 bits 0-5: start sector, bits 6-7: bits 8-9 of start track
	BYTE starttrack;		// 03 bits 0-7 of start track
	BYTE parttype;			// 04 partition type
	BYTE endhead;			// 05 end head
	BYTE endsec;			// 06 end sector
	BYTE endtrack;			// 07 end track
	DWORD bias;				// 08 sector bias to start of partition
	DWORD partsize;			// 0C partition size in sectors
	} PARTITION, *PPARTITION;

typedef struct tagBOOTSECT
	{						// boot sector
	BYTE jmpinst[3];		//  00 JMP to boot code
	char vendid[8];			//  03 vendor id
	struct tagBPB;			//  0B bios parameter block
	WORD tracksectors;		//  18 # sectors per track
	WORD numtracks;			//  1A # heads (tracks)
	DWORD numhidden;		//  1C # hidden sectors
	DWORD totsectors;		//  20 # sectors if disk > 32 MB
	BYTE drive;				//  24 physical drive #
	BYTE rsv1;				//  25 reserved
	BYTE xboot;				//  26 extended boot signature (29h)
	DWORD volid;			//  27 volume ID
	char label[11];			//  2B volume label
	char fattype[8];		//  36 FAT12 or FAT16 plus 3 spaces
	BYTE junk[384];			//  3E other stuff, including bootstrap loader
	PARTITION part[4];		// 1BE partition table
	WORD signature;			// 1FE signature (0xAA55)
	} BOOTSECT, *PBOOTSECT; // boot sector [200]
/*
//the structure of the direct_entry.
typedef struct  _DIR_ENTRY
{
	UCHAR       deName[8];          // File Name
	UCHAR       deExtension[3];     // File Extension
	UCHAR       deAttributes;       // File Attributes
	UCHAR       deReserved;         // Reserved
	USHORT      deTime;             // File Time
	USHORT      deDate;             // File Date
	USHORT      deStartCluster;     // First Cluster of file
	ULONG       deFileSize;         // File Length
}DIR_ENTRY, *PDIR_ENTRY;
*/
/*
// Declare the device parameters structure. This is defined by DOS, 
// and used for IOCTL calls.
typedef struct tagDeviceParams 
{
	BYTE	dpSpecFunc;
	BYTE	dpDevType;
	WORD	dpDevAttr;
	WORD	dpCylinders;
	BYTE	dpMediaType;
	WORD	dpBytesPerSector;
	BYTE	dpSectorsPerCluster;
	WORD	dpReservedSectors;
	BYTE	dpFATs;
	WORD	dpRootDirectoryEntries;
	WORD	dpSectors;
	BYTE	dpMedia;
	WORD	dpSectorsPerFAT;
	WORD	dpSectorsPerTrack;
	WORD	dpHeads;
	DWORD	dpHiddenSectors;
	DWORD	dpHugeSectors;        
} DEVICEPARAMS, *PDEVICEPARAMS;
*/

/*
// Declare the media ID structure. This is defined by DOS, and used 
// for IOCTL calls.
typedef struct tagMediaID 
{
	WORD	midInfoLevel;
	DWORD	midSerialNum;
	CHAR	midVolLable[11];
	CHAR	midFileSysType[8];
} MEDIAID, *PMEDIAID;
*/
/*
// RAMDISK private handle structure for FindFirst/FindNext operations
typedef struct _findcontext
{
	ULONG	fc_sig;		// must be SIGFIND
	HKEY	fc_hkey;	// registry key
	HKEY	fc_index;	// subkey index
	PWORD	fc_match;	// meta match specification
	BOOL	fc_bKeysDone;	// TRUE if all keys enumerated
} FINDCONTEXT, *PFINDCONTEXT;
*/
/*
// RAMDISK private handle structure for Open File operations
typedef struct _regfsdhandle
{
	ULONG	h_sig;		// must be SIGFILE
	HKEY	h_key;		// registry KEY
	PCHAR	h_value;	// value name
	ULONG	h_size;		// value size
	ULONG	h_pos;		// current position
} RAMDISKHANDLE, *PRAMDISKHANDLE;
*/

/*
typedef struct _USBDDB
{
	IOSDDB      Ddb;
//	DWORD    Signature;
//	DWORD    Fdo;
	DWORD    Flags;
//	DWORD    Dcb1;
//	DWORD    Dcb2;
//	BYTE     Cdb[12];
//	IOPACKET IoPacket;
}USBDDB, *PUSBDDB;
*/
/*
// Structure used by debug routines to associate strings to constants
typedef struct _name_assoc 
{
	BYTE _func;
	const char* _name;
} NAMETABLE;
*/
/////////////////////////////////////////////////////////////////////
// Function prototypes

//INT RegMountVolume(pioreq pir);
VOID __cdecl RAMDISK_RequestHandler(IOP* pIop);
VOID SetupDCB(DCB* pDcb);

//BYTE AssociateDriveLetter(DCB_COMMON* pDcb);

/////////////////////////////////////////////////////////////////////
// Global data

// Assigned drive letter designator (0=A)

//extern BYTE Drive;

// Pointer the drive's physical DCB

//extern DCB* pDcbOfThisDevice;

// Array of names of the six predefined Registry root keys
//extern PCHAR PredefinedRegKeyStrings[NPREDEFKEYS];
// Array of values of the six predefined Registry root keys
//extern INT PredefinedRegKeyValues[NPREDEFKEYS];
// The volume handle passed to the mount routine

//extern VRP* VolumeHandle;

// The driver's IOS linkage block
extern ILB RAMDISK_Ilb;

extern char base[DISKSIZE];

extern IOSDDB* pDDB;