195 lines
4.8 KiB
C
195 lines
4.8 KiB
C
/*++
|
||
|
||
Copyright (c) 1991 Microsoft Corporation
|
||
|
||
Module Name:
|
||
|
||
fatboot.h
|
||
|
||
Abstract:
|
||
|
||
This module defines globally used procedure and data structures used
|
||
by fat boot.
|
||
|
||
Author:
|
||
|
||
Gary Kimura (garyki) 29-Aug-1989
|
||
|
||
Revision History:
|
||
|
||
--*/
|
||
|
||
#ifndef _FATBOOT_
|
||
#define _FATBOOT_
|
||
#include "fat.h"
|
||
|
||
|
||
//
|
||
// The following structure is used to define the local mcb structure used within
|
||
// the fat boot loader to maintain a small cache of the retrieval information
|
||
// for a single file/directory
|
||
//
|
||
|
||
#define FAT_MAXIMUM_MCB (41)
|
||
|
||
typedef struct _FAT_MCB {
|
||
|
||
//
|
||
// The following fields indicate the number of entries in use by
|
||
// the boot mcb. and the boot mcb itself. The boot mcb is
|
||
// just a collection of [vbo, lbo] pairs. The last InUse entry
|
||
// Lbo's value is ignored, because it is only used to give the
|
||
// length of the previous run.
|
||
//
|
||
|
||
ULONG InUse;
|
||
|
||
VBO Vbo[ FAT_MAXIMUM_MCB ];
|
||
LBO Lbo[ FAT_MAXIMUM_MCB ];
|
||
|
||
} FAT_MCB, *PFAT_MCB;
|
||
|
||
//
|
||
// The following structure is used to define the geometry of the fat volume
|
||
// There is one for every mounted volume. It describes the size/configuration
|
||
// of the volume, contains a small cached mcb for the last file being accessed
|
||
// on the volume, and contains a small cache of the fat. Given a FileId we
|
||
// can access the structure context through the structure context field in the
|
||
// global BlFileTable (e.g., BlFileTable[FileId].StructureContext).
|
||
//
|
||
|
||
//
|
||
// The following constant is used to determine how much of the fat we keep
|
||
// cached in memory at any one time. It must be a multiple of 6 bytes in order to
|
||
// hold complete 12 and 16 bit fat entries in the cache at any one time.
|
||
//
|
||
|
||
#define FAT_CACHE_SIZE (512*3)
|
||
|
||
typedef struct _FAT_STRUCTURE_CONTEXT {
|
||
|
||
//
|
||
// The following field contains an unpacked copy of the bios parameter block
|
||
// for the mounted volume
|
||
//
|
||
|
||
BIOS_PARAMETER_BLOCK Bpb;
|
||
|
||
//
|
||
// The following two fields contain current file id of the file/directory
|
||
// whose mcb we are keeping around, and the second field is the mcb itself
|
||
//
|
||
|
||
ULONG FileId;
|
||
FAT_MCB Mcb;
|
||
|
||
//
|
||
// The following fields describe/contain the current cached fat. The vbo
|
||
// is the smallest vbo of the fat currently in the cache, and cached fat
|
||
// is a pointer to the cached data. The extra buffer/indirectiion is needed
|
||
// to keep everything aligned properly. The dirty flag is used to indicate
|
||
// if the current cached fat has been modified and needs to be flushed to disk.
|
||
// Vbo is used because this allows us to do a lot of our computations having
|
||
// already biased lbo offset to the first fat table.
|
||
//
|
||
|
||
BOOLEAN CachedFatDirty;
|
||
VBO CachedFatVbo;
|
||
PUCHAR CachedFat;
|
||
UCHAR CachedFatBuffer[ FAT_CACHE_SIZE + 256 ];
|
||
|
||
} FAT_STRUCTURE_CONTEXT, *PFAT_STRUCTURE_CONTEXT;
|
||
|
||
//
|
||
// The following structure is used to define the location and size of each
|
||
// opened file. There is one of these of every opened file. It is part of
|
||
// the union of a BL_FILE_TABLE structuure. Given a FileId we can access the
|
||
// file context via the BlFileTable (e.g., BlFileTable[FileId].u.FatFileContext)
|
||
//
|
||
|
||
typedef struct _FAT_FILE_CONTEXT {
|
||
|
||
//
|
||
// The following two fields describe where on the disk the dirent for the
|
||
// file is located and also contains a copy of the dirent
|
||
//
|
||
|
||
LBO DirentLbo;
|
||
DIRENT Dirent;
|
||
|
||
} FAT_FILE_CONTEXT, *PFAT_FILE_CONTEXT;
|
||
|
||
|
||
//
|
||
// Define file I/O prototypes.
|
||
//
|
||
|
||
ARC_STATUS
|
||
FatClose (
|
||
IN ULONG FileId
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatOpen (
|
||
IN CHAR * FIRMWARE_PTR OpenPath,
|
||
IN OPEN_MODE OpenMode,
|
||
OUT ULONG * FIRMWARE_PTR FileId
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatRead (
|
||
IN ULONG FileId,
|
||
OUT VOID * FIRMWARE_PTR Buffer,
|
||
IN ULONG Length,
|
||
OUT ULONG * FIRMWARE_PTR Count
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatSeek (
|
||
IN ULONG FileId,
|
||
IN LARGE_INTEGER * FIRMWARE_PTR Offset,
|
||
IN SEEK_MODE SeekMode
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatWrite (
|
||
IN ULONG FileId,
|
||
IN VOID * FIRMWARE_PTR Buffer,
|
||
IN ULONG Length,
|
||
OUT ULONG * FIRMWARE_PTR Count
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatGetFileInformation (
|
||
IN ULONG FileId,
|
||
OUT FILE_INFORMATION * FIRMWARE_PTR Buffer
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatSetFileInformation (
|
||
IN ULONG FileId,
|
||
IN ULONG AttributeFlags,
|
||
IN ULONG AttributeMask
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatRename(
|
||
IN ULONG FileId,
|
||
IN CHAR * FIRMWARE_PTR NewFileName
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatGetDirectoryEntry (
|
||
IN ULONG FileId,
|
||
IN DIRECTORY_ENTRY * FIRMWARE_PTR DirEntry,
|
||
IN ULONG NumberDir,
|
||
OUT ULONG * FIRMWARE_PTR CountDir
|
||
);
|
||
|
||
ARC_STATUS
|
||
FatInitialize(
|
||
VOID
|
||
);
|
||
|
||
#endif // _FATBOOT_
|