NT4/private/ole32/stg/h/fat.hxx
2020-09-30 17:12:29 +02:00

706 lines
16 KiB
C++

//+-------------------------------------------------------------------
//
// Microsoft Windows
// Copyright (C) Microsoft Corporation, 1992 - 1992.
//
// File: fat.hxx
//
// Contents: Header file for fat classes
//
// Classes: CFatSect - sector sized array of sector info
// CFatVector - resizable array of CFatSect
// CFat - Grouping of FatSect
//
// History: 18-Jul-91 PhilipLa Created.
//
//--------------------------------------------------------------------
#ifndef __FAT_HXX__
#define __FAT_HXX__
#include <vect.hxx>
#define DEB_FAT (DEB_ITRACE|0x00010000)
//+----------------------------------------------------------------------
//
// Class: CFatSect (fs)
//
// Purpose: Holds one sector worth of FAT data
//
// Interface: getsize - Returns the size of the FAT (in sectors)
// contents - Returns contents of any given FAT entry
//
// History: 18-Jul-91 PhilipLa Created.
//
// Notes:
//
//-----------------------------------------------------------------------
#if _MSC_VER == 700
#pragma warning(disable:4001)
#elif _MSC_VER >= 800
#pragma warning(disable:4200)
#endif
class CFatSect
{
public:
SCODE FAT_CLASS Init(FSOFFSET uEntries);
SCODE FAT_CLASS InitCopy(USHORT uSize, CFatSect *pfsOld);
inline SECT FAT_CLASS GetSect(const FSOFFSET sect) const;
inline void FAT_CLASS SetSect(const FSOFFSET sect,const SECT sectNew);
inline SECT FAT_CLASS GetNextFat(USHORT uSize) const;
inline void FAT_CLASS SetNextFat(USHORT uSize, const SECT sect);
private:
SECT _asectEntry[];
};
#if _MSC_VER == 700
#pragma warning(default:4001)
#elif _MSC_VER >= 800
#pragma warning(default:4200)
#endif
inline SECT FAT_CLASS CFatSect::GetSect(const FSOFFSET sect) const
{
return _asectEntry[sect];
}
inline void FAT_CLASS CFatSect::SetSect(const FSOFFSET sect,
const SECT sectNew)
{
_asectEntry[sect] = sectNew;
}
inline SECT FAT_CLASS CFatSect::GetNextFat(USHORT uSize) const
{
return _asectEntry[uSize];
}
inline void FAT_CLASS CFatSect::SetNextFat(USHORT uSize, const SECT sect)
{
_asectEntry[uSize] = sect;
}
//+-------------------------------------------------------------------------
//
// Class: CFatVector (fv)
//
// Purpose: *Finish This*
//
// Interface:
//
// History: 02-Sep-92 PhilipLa Created.
//
// Notes:
//
//--------------------------------------------------------------------------
class CFatVector: public CPagedVector
{
public:
inline FAT_CLASS CFatVector(
const SID sid);
inline void FAT_CLASS InitCommon(FSOFFSET csectBlock, FSOFFSET csectTable);
SCODE FAT_CLASS InitPage(FSINDEX iPage);
inline FSOFFSET GetSectBlock() const;
inline FSOFFSET GetSectTable() const;
inline SCODE FAT_CLASS GetTable(
const FSINDEX iTable,
const DWORD dwFlags,
CFatSect **pfs);
private:
FSOFFSET _csectTable;
FSOFFSET _csectBlock;
};
inline FAT_CLASS CFatVector::CFatVector(
const SID sid)
: CPagedVector(sid)
{
}
inline void FAT_CLASS CFatVector::InitCommon(
FSOFFSET csectBlock,
FSOFFSET csectTable)
{
_csectBlock = csectBlock;
_csectTable = csectTable;
}
//+-------------------------------------------------------------------------
//
// Method: CFatVector::GetSectTable, public
//
// Synopsis: Returns count of sector entries per table
//
// Returns: count of sector entries per table
//
// History: 08-Jul-92 AlexT Created.
//
//--------------------------------------------------------------------------
inline FSOFFSET CFatVector::GetSectTable() const
{
return _csectTable;
}
//+-------------------------------------------------------------------------
//
// Method: CFatVector::GetSectTable, public
//
// Synopsis: Returns count of sector entries per block
//
// Returns: count of sector entries per block
//
// History: 01-Sep-92 PhilipLa Created.
//
//--------------------------------------------------------------------------
inline FSOFFSET CFatVector::GetSectBlock() const
{
return _csectBlock;
}
//+-------------------------------------------------------------------------
//
// Method: CFatVector::GetTable, public
//
// Synopsis: Return a pointer to a FatSect for the given index
// into the vector.
//
// Arguments: [iTable] -- index into vector
//
// Returns: Pointer to CFatSect indicated by index
//
// History: 27-Dec-91 PhilipLa Created.
//
// Notes:
//
//--------------------------------------------------------------------------
inline SCODE FAT_CLASS CFatVector::GetTable(
const FSINDEX iTable,
const DWORD dwFlags,
CFatSect **ppfs)
{
SCODE sc;
sc = CPagedVector::GetTable(iTable, dwFlags, (void **)ppfs);
if (sc == STG_S_NEWPAGE)
{
(*ppfs)->Init(_csectBlock);
}
return sc;
}
//CSEG determines the maximum number of segments that will be
//returned by a single Contig call.
#define CSEG 32
//+-------------------------------------------------------------------------
//
// Class: SSegment (seg)
//
// Purpose: Used for contiguity tables for multi-sector reads and
// writes.
//
// Interface: None.
//
// History: 16-Aug-91 PhilipLa Created.
//
// Notes:
//
//--------------------------------------------------------------------------
struct SSegment {
public:
ULONG ulOffset;
SECT sectStart;
ULONG cSect;
};
inline SECT SegStart(SSegment seg)
{
return seg.sectStart;
}
inline SECT SegEnd(SSegment seg)
{
return seg.sectStart + seg.cSect - 1;
}
inline ULONG SegLength(SSegment seg)
{
return seg.cSect;
}
inline ULONG SegStartOffset(SSegment seg)
{
return seg.ulOffset;
}
inline ULONG SegEndOffset(SSegment seg)
{
return seg.ulOffset + seg.cSect - 1;
}
class MSTREAM_CLASS CMStream;
#define GF_READONLY TRUE
#define GF_WRITE FALSE
class CFat;
SAFE_DFBASED_PTR(CBasedFatPtr, CFat);
//+----------------------------------------------------------------------
//
// Class: CFat (fat)
//
// Purpose: Main interface to allocation routines
//
// Interface: Allocate - allocates new chain in the FAT
// Extend - Extends an existing FAT chain
// GetNext - Returns next sector in a chain
// GetSect - Returns nth sector in a chain
// GetESect - Returns nth sector in a chain, extending
// if necessary
// GetLength - Returns the # of sectors in a chain
// setup - Initializes for an existing stream
// setupnew - Initializes for a new stream
//
// checksanity - Debugging routine
//
// History: 18-Jul-91 PhilipLa Created.
// 17-Aug-91 PhilipLa Added dirty and full bits
// Notes:
//
//-----------------------------------------------------------------------
struct SGetFreeStruct;
class CFat
{
public:
FAT_CLASS CFat(SID sid);
FAT_CLASS CFat(CFat *pfatOld);
FAT_CLASS ~CFat();
VOID FAT_CLASS Empty(VOID);
#ifdef USE_NOSCRATCH
inline void SetNoScratch(CFat *pfatNoScratch);
#endif
#ifdef USE_NOSNAPSHOT
inline void SetNoSnapshot(SECT sectNoSnapshot);
inline SECT GetNoSnapshotFree(void);
inline void ResetNoSnapshotFree(void);
SCODE ResizeNoSnapshot(void);
#endif
inline SCODE FAT_CLASS Allocate(ULONG ulSize, SECT *psectFirst);
SCODE FAT_CLASS GetNext(const SECT sect, SECT * psRet);
SCODE FAT_CLASS GetSect(
SECT sectStart,
ULONG ulOffset,
SECT *psectReturn);
SCODE FAT_CLASS GetESect(
SECT sectStart,
ULONG ulOffset,
SECT *psectReturn);
SCODE FAT_CLASS SetNext(SECT sectFirst, SECT sectNext);
SCODE FAT_CLASS GetFree(ULONG ulCount, SECT * sect, BOOL fReadOnly);
SCODE FAT_CLASS GetFreeContig(ULONG ulCount,
SSegment STACKBASED *aseg,
ULONG cSeg,
ULONG *pcSegReturned);
SCODE FAT_CLASS ReserveSects(ULONG cSect);
SCODE FAT_CLASS GetLength(SECT sect, ULONG * pulRet);
SCODE FAT_CLASS SetChainLength(SECT,ULONG);
SCODE FAT_CLASS Init(
CMStream *pmsParent,
FSINDEX cFatSect,
BOOL fConvert);
SCODE FAT_CLASS InitNew(CMStream *pmsParent);
void FAT_CLASS InitCopy(CFat *pfatOld);
SCODE FAT_CLASS InitConvert(
CMStream *pmsParent,
ULONG cbSize);
#ifdef USE_NOSCRATCH
SCODE FAT_CLASS InitScratch(CFat *pfat, BOOL fNew);
#endif
SCODE FAT_CLASS Remap(
SECT sectStart,
ULONG oStart,
ULONG ulRunLength,
SECT *psectOldStart,
SECT *psectNewStart,
SECT *psectOldEnd,
SECT *psectNewEnd);
inline SCODE FAT_CLASS QueryRemapped(const SECT sect);
inline SECT FAT_CLASS GetLast(VOID) const;
inline VOID FAT_CLASS ResetCopyOnWrite(VOID);
inline VOID FAT_CLASS SetCopyOnWrite(CFat *pfat, SECT sectLast);
inline VOID FAT_CLASS ResetUnmarkedSects(VOID);
SCODE FAT_CLASS FindLast(SECT *psectRet);
SCODE FAT_CLASS FindMaxSect(SECT *psectRet);
inline SCODE FAT_CLASS GetMaxSect(SECT *psectRet);
SCODE FAT_CLASS Contig(
SSegment STACKBASED *aseg,
BOOL fWrite,
SECT sect,
ULONG ulLength,
ULONG *pcSeg);
inline SCODE FAT_CLASS Flush(VOID);
inline void FAT_CLASS SetParent(CMStream *pms);
SCODE FAT_CLASS Resize(ULONG);
#if DBG == 1
SCODE FAT_CLASS checksanity(SECT);
void CheckFreeCount(void);
#else
#define CheckFreeCount()
#endif
private:
inline SCODE IsFree(SECT sect);
inline SCODE FAT_CLASS MarkSect(SGetFreeStruct *pgf);
inline void FAT_CLASS InitGetFreeStruct(SGetFreeStruct *pgf);
inline void FAT_CLASS ReleaseGetFreeStruct(SGetFreeStruct *pgf);
CFatVector _fv;
CBasedMStreamPtr _pmsParent;
const SID _sid;
CBasedFatPtr _pfatReal;
#ifdef USE_NOSCRATCH
CBasedFatPtr _pfatNoScratch;
#endif
#ifdef USE_NOSNAPSHOT
//When committing in no-snapshot mode, all free sectors must
// be greater than _sectNoSnapshot.
SECT _sectNoSnapshot;
SECT _sectNoSnapshotFree;
#endif
USHORT _uFatShift;
USHORT _uFatMask;
FSINDEX _cfsTable;
ULONG _ulFreeSects;
ULONG _cUnmarkedSects;
SECT _sectFirstFree;
SECT _sectLastUsed;
SECT _sectMax;
SCODE FAT_CLASS CountFree(ULONG * ulRet);
SCODE FAT_CLASS Extend(SECT,ULONG);
inline VOID FAT_CLASS SectToPair(
SECT sect,
FSINDEX *pipfs,
FSOFFSET *pisect) const;
inline SECT FAT_CLASS PairToSect(FSINDEX ipfs, FSOFFSET isect) const;
friend class CDIFat;
};
inline SECT FAT_CLASS CFat::GetLast(VOID) const
{
return _sectLastUsed;
}
inline VOID FAT_CLASS CFat::ResetCopyOnWrite(VOID)
{
_sectLastUsed = 0;
//Reset _sectFirstFree since this change can conceivably open up
// new free sectors before the _sectFirstFree used in COW mode.
_ulFreeSects = MAX_ULONG;
_sectFirstFree = 0;
_sectMax = ENDOFCHAIN;
_fv.ResetBits();
_pfatReal = NULL;
_cUnmarkedSects = 0;
}
inline VOID FAT_CLASS CFat::ResetUnmarkedSects(VOID)
{
_cUnmarkedSects = 0;
CheckFreeCount();
}
inline VOID FAT_CLASS CFat::SetCopyOnWrite(CFat *pfat, SECT sectLast)
{
msfAssert((_cUnmarkedSects == 0) &&
aMsg("Unmarked sectors at enter copy-on-write."));
_pfatReal = P_TO_BP(CBasedFatPtr, pfat);
_sectLastUsed = sectLast;
_sectFirstFree = 0;
#ifdef USE_NOSCRATCH
if (_pfatNoScratch != NULL)
{
_ulFreeSects = MAX_ULONG;
_fv.ResetBits();
}
#endif
#if DBG == 1
CheckFreeCount();
#endif
}
inline VOID FAT_CLASS CFat::SectToPair(SECT sect,
FSINDEX *pipfs,
FSOFFSET *pisect) const
{
*pipfs = (FSINDEX)(sect >> _uFatShift);
*pisect = (FSOFFSET)(sect & _uFatMask);
}
inline SECT FAT_CLASS CFat::PairToSect(FSINDEX ipfs, FSOFFSET isect) const
{
return (ipfs << _uFatShift) + isect;
}
inline SCODE FAT_CLASS CFat::GetMaxSect(SECT *psectRet)
{
SCODE sc;
msfChk(FindMaxSect(&_sectMax));
*psectRet = _sectMax;
Err:
return sc;
}
#ifdef CODESEGMENTS
#pragma code_seg(SEG_CFat_QueryRemapped)
#endif
inline SCODE FAT_CLASS CFat::QueryRemapped(const SECT sect)
{
SCODE sc = S_FALSE;
SECT sectNew;
if ((sect == ENDOFCHAIN) || (sect >= _sectLastUsed))
{
sc = S_OK;
}
else
{
msfChk(_pfatReal->GetNext(sect, &sectNew));
if (sectNew == FREESECT)
{
sc = S_OK;
}
else
{
sc = S_FALSE;
}
}
Err:
return sc;
}
#ifdef CODESEGMENTS
#pragma code_seg()
#endif
inline void FAT_CLASS CFat::SetParent(CMStream *pms)
{
_pmsParent = P_TO_BP(CBasedMStreamPtr, pms);
_fv.SetParent(pms);
}
//+-------------------------------------------------------------------------
//
// Member: CFat::Flush, public
//
// Synposis: Write all modified FatSects out to stream
//
// Effects: Resets all dirty bit fields on FatSects
//
// Arguments: Void
//
// Returns: S_OK if call completed OK.
// Error code of parent write otherwise.
//
// Algorithm: Linearly scan through FatSects, writing any sector
// that has the dirty bit set. Reset all dirty bits.
//
// History: 17-Aug-91 PhilipLa Created.
//
// Notes:
//
//---------------------------------------------------------------------------
inline SCODE FAT_CLASS CFat::Flush(VOID)
{
return _fv.Flush();
}
//+-------------------------------------------------------------------------
//
// Member: CFat::Allocate, public
//
// Synposis: Allocates a chain within a FAT
//
// Effects: Modifies a single sector within the fat. Causes a
// one sector stream write.
//
// Arguments: [ulSize] -- Number of sectors to allocate in chain
//
// Returns: Sector ID of first sector in chain
//
// Algorithm: Use repetitive calls to GetFree to construct a new chain
//
// History: 18-Jul-91 PhilipLa Created.
// 17-Aug-91 PhilipLa Added dirty bits opt (Dump)
//
// Notes:
//
//---------------------------------------------------------------------------
inline SCODE FAT_CLASS CFat::Allocate(ULONG ulSize, SECT * psectFirst)
{
return GetFree(ulSize, psectFirst, GF_WRITE);
}
#ifdef USE_NOSCRATCH
//+---------------------------------------------------------------------------
//
// Member: CFat::SetNoScratch, public
//
// Synopsis: Set the fat for use in noscratch processing
//
// Arguments: [pfatNoScratch] -- Pointer to fat to use
//
// Returns: void
//
// History: 10-Mar-95 PhilipLa Created
//
//----------------------------------------------------------------------------
inline void CFat::SetNoScratch(CFat *pfatNoScratch)
{
_pfatNoScratch = P_TO_BP(CBasedFatPtr, pfatNoScratch);
}
#endif
#ifdef USE_NOSNAPSHOT
//+---------------------------------------------------------------------------
//
// Member: CFat::SetNoSnapshot, public
//
// Synopsis: Set the no-snapshot sect marker for commits
//
// Arguments: [sectNosnapshot] -- Sect to set.
//
// Returns: void
//
// History: 18-Oct-95 PhilipLa Created
//
//----------------------------------------------------------------------------
inline void CFat::SetNoSnapshot(SECT sectNoSnapshot)
{
_sectNoSnapshot = sectNoSnapshot;
if (sectNoSnapshot != 0)
{
_ulFreeSects = MAX_ULONG;
_sectNoSnapshotFree = _sectNoSnapshot;
_sectMax = _sectNoSnapshot;
#if DBG == 1
SCODE sc;
SECT sectLast;
msfChk(FindLast(&sectLast));
msfAssert((_sectMax == sectLast) &&
aMsg("_sectMax doesn't match actual last sector"));
Err:
;
#endif
}
}
inline SECT CFat::GetNoSnapshotFree(void)
{
return _sectNoSnapshotFree;
}
inline void CFat::ResetNoSnapshotFree(void)
{
_sectNoSnapshotFree = ENDOFCHAIN;
}
#endif
#endif //__FAT_HXX__