745 lines
22 KiB
C++
745 lines
22 KiB
C++
//+---------------------------------------------------------------------------
|
|
//
|
|
// Microsoft Windows
|
|
// Copyright (C) Microsoft Corporation, 1995
|
|
//
|
|
// File: PropRec.cxx
|
|
//
|
|
// Contents: Record format for persistent property store
|
|
//
|
|
// Classes: CPropertyRecord
|
|
//
|
|
// History: 28-Dec-19 KyleP Created
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
#include <pch.cxx>
|
|
#pragma hdrstop
|
|
|
|
#include <stgvar.hxx>
|
|
#include <propvar.h>
|
|
#include <propstm.hxx>
|
|
#include <proprec.hxx>
|
|
#include <eventlog.hxx>
|
|
|
|
class CCTMABufferAllocator : public PMemoryAllocator
|
|
{
|
|
public:
|
|
|
|
void *Allocate(ULONG cbSize)
|
|
{
|
|
return CoTaskMemAlloc( cbSize );
|
|
}
|
|
|
|
void Free(void *pv)
|
|
{
|
|
CoTaskMemFree( pv );
|
|
}
|
|
};
|
|
|
|
class CNonAlignAllocator : public PMemoryAllocator
|
|
{
|
|
public:
|
|
inline CNonAlignAllocator(ULONG cbBuffer, VOID *pvBuffer)
|
|
{
|
|
_cbFree = cbBuffer;
|
|
_pvCur = _pvBuffer = pvBuffer;
|
|
}
|
|
|
|
VOID *Allocate(ULONG cb)
|
|
{
|
|
VOID *pv;
|
|
|
|
cb = (cb + sizeof(LONGLONG) - 1) & ~(sizeof(LONGLONG) - 1);
|
|
if (cb > _cbFree)
|
|
{
|
|
return(NULL);
|
|
}
|
|
pv = _pvCur;
|
|
_pvCur = (BYTE *) _pvCur + cb;
|
|
_cbFree -= cb;
|
|
return(pv);
|
|
}
|
|
|
|
VOID Free(VOID *pv) { }
|
|
|
|
inline ULONG GetFreeSize(VOID) { return(_cbFree); }
|
|
|
|
private:
|
|
ULONG _cbFree;
|
|
VOID *_pvCur;
|
|
VOID *_pvBuffer;
|
|
};
|
|
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::ReadFixed, public
|
|
//
|
|
// Synopsis: Read fixed-length property
|
|
//
|
|
// Arguments: [Ordinal] -- Ordinal of property to locate.
|
|
// [mask] -- Bitmask of ordinal. Pre-computed for efficiency.
|
|
// [oStart] -- Offset to start of specific fixed property.
|
|
// [cTotal] -- Total number of properties in record.
|
|
// [Type] -- Data type of value
|
|
// [var] -- Value returned here.
|
|
// [pbExtra] -- Indirect data stored here
|
|
// [pcbExtra] -- On input, size of [pbExtra]. On output,
|
|
// amount used.
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
void COnDiskPropertyRecord::ReadFixed( ULONG Ordinal,
|
|
ULONG Mask,
|
|
ULONG oStart,
|
|
ULONG cTotal,
|
|
ULONG Type,
|
|
PROPVARIANT & var,
|
|
BYTE * pbExtra,
|
|
unsigned * pcbExtra )
|
|
{
|
|
if ( !IsStored( Ordinal, Mask ) )
|
|
{
|
|
var.vt = VT_EMPTY;
|
|
*pcbExtra = 0;
|
|
}
|
|
else
|
|
{
|
|
var.vt = (USHORT)Type;
|
|
|
|
//
|
|
// Start is after existance bitmap
|
|
//
|
|
|
|
ULONG const * pulStart = &_aul[ (cTotal-1) / 16 + 1 + oStart];
|
|
|
|
switch ( Type )
|
|
{
|
|
case VT_I1:
|
|
case VT_UI1:
|
|
var.bVal = *(BYTE *)pulStart;
|
|
*pcbExtra = 0;
|
|
break;
|
|
|
|
case VT_I2:
|
|
case VT_UI2:
|
|
case VT_BOOL:
|
|
var.uiVal = *(USHORT *)pulStart;
|
|
*pcbExtra = 0;
|
|
break;
|
|
|
|
case VT_I4:
|
|
case VT_UI4:
|
|
case VT_R4:
|
|
case VT_ERROR:
|
|
var.ulVal = *pulStart;
|
|
*pcbExtra = 0;
|
|
break;
|
|
|
|
case VT_I8:
|
|
case VT_UI8:
|
|
case VT_R8:
|
|
case VT_CY:
|
|
case VT_DATE:
|
|
case VT_FILETIME:
|
|
RtlCopyMemory( &var.hVal, pulStart, sizeof(var.hVal) );
|
|
*pcbExtra = 0;
|
|
break;
|
|
|
|
case VT_CLSID:
|
|
if ( *pcbExtra < sizeof(CLSID) )
|
|
{
|
|
*pcbExtra = sizeof(CLSID);
|
|
return;
|
|
}
|
|
|
|
if ( *pcbExtra == 0xFFFFFFFF )
|
|
var.puuid = (CLSID *)CoTaskMemAlloc( sizeof(CLSID) );
|
|
else
|
|
{
|
|
*pcbExtra = sizeof(CLSID);
|
|
var.puuid = (CLSID *)pbExtra;
|
|
}
|
|
RtlCopyMemory( var.puuid, pulStart, sizeof(CLSID) );
|
|
break;
|
|
|
|
default:
|
|
ciDebugOut(( DEB_ERROR, "PROPSTORE: Reading invalid fixed type %d.\n", Type ));
|
|
Win4Assert( !"How did I get here?" );
|
|
ReportCorruptComponent( L"PropertyRecord1" );
|
|
THROW( CException( CI_CORRUPT_DATABASE ) );
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::ReadVariable, public
|
|
//
|
|
// Synopsis: Read variable-length property
|
|
//
|
|
// Arguments: [Ordinal] -- Ordinal of property to locate.
|
|
// [mask] -- Bitmask of ordinal. Pre-computed for efficiency.
|
|
// [oStart] -- Offset to start of variable storage area.
|
|
// [cTotal] -- Total number of properties in record.
|
|
// [cFixed] -- Count of fixed length properties
|
|
// [var] -- Value returned here.
|
|
// [pbExtra] -- Indirect data stored here
|
|
// [pcbExtra] -- On input, size of [pbExtra]. On output,
|
|
// amount used.
|
|
//
|
|
// Returns: FALSE if value must be stored in overflow record.
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
BOOL COnDiskPropertyRecord::ReadVariable( ULONG Ordinal,
|
|
ULONG Mask,
|
|
ULONG oStart,
|
|
ULONG cTotal,
|
|
ULONG cFixed,
|
|
PROPVARIANT & var,
|
|
BYTE * pbExtra,
|
|
unsigned * pcbExtra )
|
|
{
|
|
if ( !IsStored( Ordinal, Mask ) )
|
|
{
|
|
var.vt = VT_EMPTY;
|
|
*pcbExtra = 0;
|
|
}
|
|
else
|
|
{
|
|
//
|
|
// Check for overflow.
|
|
//
|
|
|
|
if ( IsStoredOnOverflow( Ordinal, Mask ) )
|
|
return FALSE;
|
|
|
|
//
|
|
// Start is after existance bitmap and fixed properties.
|
|
//
|
|
|
|
ULONG * pulStart = FindVariableProp( Ordinal, cFixed, cTotal, oStart );
|
|
|
|
Win4Assert( !IsOverflow( *pulStart ) );
|
|
|
|
//
|
|
// Compute the length of the property.
|
|
//
|
|
|
|
ULONG cbProp = UsedSize( *pulStart ) * 4;
|
|
pulStart++; // Skip size field.
|
|
|
|
ciDebugOut(( DEB_PROPSTORE,
|
|
"Reading variable prop, ordinal %d at offset 0x%x (%d) in record. Size = %d bytes.\n",
|
|
Ordinal,
|
|
(ULONG)pulStart - (ULONG)this,
|
|
(ULONG)pulStart - (ULONG)this,
|
|
cbProp ));
|
|
|
|
ULONG cb = PropertyLengthAsVariant( (SERIALIZEDPROPERTYVALUE *)pulStart,
|
|
cbProp,
|
|
CP_WINUNICODE,
|
|
0 );
|
|
|
|
if ( cb <= *pcbExtra )
|
|
{
|
|
if ( *pcbExtra == 0xFFFFFFFF )
|
|
{
|
|
//
|
|
// Unmarshall the property. Extra allocation via CoTaskMemAlloc
|
|
//
|
|
|
|
CCTMABufferAllocator BufferMgr;
|
|
|
|
RtlConvertPropertyToVariant( (SERIALIZEDPROPERTYVALUE *)pulStart,
|
|
CP_WINUNICODE,
|
|
&var,
|
|
&BufferMgr );
|
|
|
|
#if CIDBG==1
|
|
if ( (var.vt&0x0fff) > VT_CLSID )
|
|
{
|
|
ciDebugOut(( DEB_ERROR, "Bad Variant Type 0x%X\n", var.vt ));
|
|
Win4Assert( !"Call KyleP" );
|
|
}
|
|
#endif // CIDBG==1
|
|
|
|
}
|
|
else
|
|
{
|
|
//
|
|
// Unmarshall the property.
|
|
//
|
|
|
|
CNonAlignAllocator BufferMgr( *pcbExtra, pbExtra );
|
|
|
|
RtlConvertPropertyToVariant( (SERIALIZEDPROPERTYVALUE *)pulStart,
|
|
CP_WINUNICODE,
|
|
&var,
|
|
&BufferMgr );
|
|
#if CIDBG==1
|
|
if ( (var.vt&0x0fff) > VT_CLSID )
|
|
{
|
|
ciDebugOut(( DEB_ERROR, "Bad Variant Type 0x%X\n", var.vt ));
|
|
Win4Assert( !"Call KyleP" );
|
|
}
|
|
#endif // CIDBG==1
|
|
|
|
}
|
|
}
|
|
*pcbExtra = cb;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::WriteFixed, public
|
|
//
|
|
// Synopsis: Write fixed-length property
|
|
//
|
|
// Arguments: [Ordinal] -- Ordinal of property to locate.
|
|
// [mask] -- Bitmask of ordinal. Pre-computed for efficiency.
|
|
// [oStart] -- Offset to start of specific property.
|
|
// [Type] -- Expected data type (for type checking)
|
|
// [cTotal] -- Total number of properties in record.
|
|
// [var] -- Value to store.
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
void COnDiskPropertyRecord::WriteFixed( ULONG Ordinal,
|
|
ULONG Mask,
|
|
ULONG oStart,
|
|
ULONG Type,
|
|
ULONG cTotal,
|
|
CStorageVariant const & var )
|
|
{
|
|
if ( var.Type() != (VARENUM)Type )
|
|
{
|
|
# if CIDBG == 1
|
|
if ( var.Type() != VT_EMPTY )
|
|
ciDebugOut(( DEB_WARN, "Type mismatch (%d vs. %d) writing fixed property\n",
|
|
var.Type(), Type ));
|
|
# endif
|
|
|
|
ClearStored( Ordinal, Mask );
|
|
return;
|
|
}
|
|
|
|
//
|
|
// Start is after existance bitmap
|
|
//
|
|
|
|
ULONG * pulStart = &_aul[ (cTotal-1) / 16 + 1 + oStart];
|
|
|
|
ciDebugOut(( DEB_PROPSTORE,
|
|
"Writing fixed prop, ordinal %d (type %d) at offset 0x%x (%d) in record.\n",
|
|
Ordinal,
|
|
var.Type(),
|
|
(ULONG)pulStart - (ULONG)this,
|
|
(ULONG)pulStart - (ULONG)this ));
|
|
|
|
switch ( var.Type() )
|
|
{
|
|
case VT_I1:
|
|
case VT_UI1:
|
|
Win4Assert( !"Fix this!" );
|
|
//*(BYTE *)pulStart = var.GetUI1();
|
|
break;
|
|
|
|
case VT_I2:
|
|
case VT_UI2:
|
|
case VT_BOOL:
|
|
{
|
|
ULONG ul = var.GetUI2();
|
|
*pulStart = ul;
|
|
}
|
|
break;
|
|
|
|
case VT_I4:
|
|
case VT_UI4:
|
|
case VT_R4:
|
|
case VT_ERROR:
|
|
*pulStart = var.GetUI4();
|
|
break;
|
|
|
|
case VT_I8:
|
|
case VT_UI8:
|
|
case VT_R8:
|
|
case VT_CY:
|
|
case VT_DATE:
|
|
case VT_FILETIME:
|
|
{
|
|
ULARGE_INTEGER uli = var.GetUI8();
|
|
RtlCopyMemory( pulStart, &uli, sizeof(uli) );
|
|
}
|
|
break;
|
|
|
|
case VT_CLSID:
|
|
RtlCopyMemory( pulStart, var.GetCLSID(), sizeof(CLSID) );
|
|
break;
|
|
|
|
default:
|
|
Win4Assert( !"How did I get here?" );
|
|
ClearStored( Ordinal, Mask );
|
|
break;
|
|
}
|
|
|
|
SetStored( Ordinal, Mask );
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::WriteVariable, public
|
|
//
|
|
// Synopsis: Write variable-length property
|
|
//
|
|
// Arguments: [Ordinal] -- Ordinal of property to locate.
|
|
// [mask] -- Bitmask of ordinal. Pre-computed for efficiency.
|
|
// [oStart] -- Offset to start of variable length area.
|
|
// [cTotal] -- Total number of properties in record.
|
|
// [cFixed] -- Count of fixed length properties
|
|
// [culRec] -- Size (in dwords) of record
|
|
// [var] -- Value to store.
|
|
//
|
|
// Returns: FALSE if record must be stored in overflow record.
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
BOOL COnDiskPropertyRecord::WriteVariable( ULONG Ordinal,
|
|
ULONG Mask,
|
|
ULONG oStart,
|
|
ULONG cTotal,
|
|
ULONG cFixed,
|
|
ULONG culRec,
|
|
CStorageVariant const & var )
|
|
{
|
|
ULONG * pulStart = FindVariableProp( Ordinal, cFixed, cTotal, oStart );
|
|
|
|
//
|
|
// Are we freeing this property?
|
|
//
|
|
|
|
if ( var.Type() == VT_EMPTY )
|
|
{
|
|
ClearStored( Ordinal, Mask );
|
|
ClearStoredOnOverflow( Ordinal, Mask );
|
|
|
|
//
|
|
// Overflow case: We need to fake the overflow to clean up linked records.
|
|
//
|
|
|
|
if ( IsOverflow( *pulStart ) )
|
|
{
|
|
SetUsedSize( pulStart, 0 );
|
|
return FALSE;
|
|
}
|
|
else
|
|
{
|
|
//
|
|
// Adjust size field, and total variable space for record.
|
|
//
|
|
|
|
Win4Assert( _culVariableUsed >= UsedSize( *pulStart ) );
|
|
_culVariableUsed -= UsedSize( *pulStart );
|
|
|
|
SetUsedSize( pulStart, 0 );
|
|
|
|
return TRUE;
|
|
}
|
|
}
|
|
|
|
//
|
|
// No matter what happens, we want to indicate the property was stored.
|
|
//
|
|
|
|
SetStored( Ordinal, Mask );
|
|
ClearStoredOnOverflow( Ordinal, Mask );
|
|
|
|
|
|
//
|
|
// Compute the length of the property.
|
|
//
|
|
|
|
ULONG cul = 0;
|
|
RtlConvertVariantToProperty( (PROPVARIANT *)(ULONG)&var,
|
|
CP_WINUNICODE,
|
|
0,
|
|
&cul,
|
|
pidInvalid,
|
|
FALSE,
|
|
0 );
|
|
|
|
Win4Assert( cul > 0 );
|
|
cul = (cul - 1) / 4 + 1;
|
|
|
|
ULONG culPrevUsed = UsedSize( *pulStart );
|
|
|
|
//
|
|
// Do we fit?
|
|
//
|
|
|
|
if ( cul > AllocatedSize( *pulStart ) )
|
|
{
|
|
//
|
|
// Can we fit?
|
|
//
|
|
|
|
if ( cul >
|
|
UsedSize( *pulStart ) + FreeVariableSpace( cTotal, cFixed, oStart, culRec ) )
|
|
{
|
|
ciDebugOut(( DEB_PROPSTORE, "Need overflow buffer for ordinal %u\n", Ordinal ));
|
|
|
|
//
|
|
// If we had a previous value, adjust total variable space for record.
|
|
//
|
|
|
|
if ( !IsOverflow( *pulStart ) )
|
|
{
|
|
Win4Assert( _culVariableUsed >= UsedSize( *pulStart ) );
|
|
_culVariableUsed -= UsedSize( *pulStart );
|
|
}
|
|
|
|
MarkOverflow( pulStart );
|
|
SetStoredOnOverflow( Ordinal, Mask );
|
|
return FALSE;
|
|
}
|
|
|
|
//
|
|
// Need to move properties, but there *is* room in record for the shift.
|
|
//
|
|
|
|
//
|
|
// First, compress previous properties.
|
|
//
|
|
|
|
#if CIDBG
|
|
ULONG * pulOldStart = pulStart;
|
|
#endif
|
|
|
|
pulStart = LeftCompress( FindVariableProp( cFixed, cFixed, cTotal, oStart ),
|
|
0,
|
|
pulStart );
|
|
|
|
ciDebugOut(( DEB_PROPSTORE,
|
|
"Freeing up %d bytes for variable prop %d via left compression\n",
|
|
(pulOldStart - pulStart) * 4,
|
|
Ordinal ));
|
|
|
|
//
|
|
// Then, if needed, push additional properties farther out.
|
|
//
|
|
|
|
if ( cul > AllocatedSize( *pulStart ) )
|
|
{
|
|
ULONG * pulNext = pulStart + AllocatedSize(*pulStart) + 1;
|
|
ULONG culDelta = cul - AllocatedSize(*pulStart);
|
|
|
|
ciDebugOut(( DEB_PROPSTORE,
|
|
"Freeing up %d bytes for variable prop %d, starting at offset 0x%x (%d) via right compression\n",
|
|
culDelta * 4,
|
|
Ordinal,
|
|
(ULONG)pulNext - (ULONG)this,
|
|
(ULONG)pulNext - (ULONG)this ));
|
|
|
|
Win4Assert( Ordinal < cTotal );
|
|
|
|
RightCompress( pulNext, // Next property
|
|
culDelta, // Amount to shift
|
|
cTotal - Ordinal - 1 ); // # props left in record
|
|
|
|
SetAllocatedSize( pulStart, cul );
|
|
}
|
|
|
|
Win4Assert( cul <= AllocatedSize( *pulStart ) );
|
|
}
|
|
|
|
//
|
|
// Adjust size field, and total variable space for record.
|
|
//
|
|
|
|
_culVariableUsed += cul - culPrevUsed;
|
|
|
|
SetUsedSize( pulStart, cul );
|
|
pulStart++; // Skip size field
|
|
|
|
Win4Assert( AllocatedSize( *(pulStart - 1)) >= UsedSize( *(pulStart - 1) ) );
|
|
ciDebugOut(( DEB_PROPSTORE,
|
|
"Writing variable prop, ordinal %d at offset 0x%x (%d) in record. Size = %d bytes.\n",
|
|
Ordinal,
|
|
(ULONG)pulStart - (ULONG)this,
|
|
(ULONG)pulStart - (ULONG)this,
|
|
UsedSize(*(pulStart - 1)) * 4 ));
|
|
|
|
cul *= 4;
|
|
if ( 0 == RtlConvertVariantToProperty( (PROPVARIANT *)(ULONG)&var,
|
|
CP_WINUNICODE,
|
|
(SERIALIZEDPROPERTYVALUE *)pulStart,
|
|
&cul,
|
|
pidInvalid,
|
|
FALSE,
|
|
0 ) )
|
|
{
|
|
ciDebugOut(( DEB_ERROR, "Error marshalling property!\n" ));
|
|
ReportCorruptComponent( L"PropertyRecord2" );
|
|
THROW( CException( CI_CORRUPT_DATABASE ) );
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::CountRecordsToStore, public
|
|
//
|
|
// Synopsis: Compute size of value
|
|
//
|
|
// Arguments: [cTotal] -- Total number of properties in record.
|
|
// [culRec] -- Size (in dwords) of record
|
|
// [var] -- Value to store.
|
|
//
|
|
// Returns: Size in records needed to store property.
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
ULONG COnDiskPropertyRecord::CountRecordsToStore( ULONG cTotal,
|
|
ULONG culRec,
|
|
CStorageVariant const & var )
|
|
{
|
|
//
|
|
// Compute the length of the property.
|
|
//
|
|
|
|
ULONG cul = 0;
|
|
RtlConvertVariantToProperty( (PROPVARIANT *)(ULONG)&var,
|
|
CP_WINUNICODE,
|
|
0,
|
|
&cul,
|
|
pidInvalid,
|
|
FALSE,
|
|
0 );
|
|
|
|
Win4Assert( cul > 0 );
|
|
cul = (cul - 1) / 4 + 1;
|
|
|
|
//
|
|
// Add on the fixed overhead.
|
|
//
|
|
|
|
cul += FixedOverhead() + // Fixed overhead
|
|
(cTotal - 1) / 16 + 1 + // Existence bitmap
|
|
cTotal; // Used/Alloc sizes
|
|
|
|
return (cul - 1) / culRec + 1;
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::RightCompress, public
|
|
//
|
|
// Synopsis: Moves data from [pul], [cul] dwords up.
|
|
//
|
|
// Arguments: [pul] -- Start of area to move.
|
|
// [cul] -- Count of dwords to move
|
|
// [cRemaining] -- Count of values remaining in buffer. Needed
|
|
// because it is impossible to distinguish
|
|
// used/alloc blocks from empty space.
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
void COnDiskPropertyRecord::RightCompress( ULONG * pul, ULONG cul, ULONG cRemaining )
|
|
{
|
|
//
|
|
// Termination condition for recursion: We've scanned all variable
|
|
// properties in this record. Any remaining space in record is
|
|
// guaranteed to be free.
|
|
//
|
|
|
|
if ( 0 == cRemaining )
|
|
return;
|
|
|
|
ULONG FreeSpace = AllocatedSize(*pul) - UsedSize(*pul);
|
|
if ( FreeSpace >= cul )
|
|
{
|
|
SetAllocatedSize( pul, AllocatedSize(*pul) - cul );
|
|
}
|
|
else
|
|
{
|
|
RightCompress( pul + AllocatedSize(*pul) + 1, cul - FreeSpace, cRemaining - 1 );
|
|
SetAllocatedSize( pul, UsedSize(*pul) );
|
|
}
|
|
RtlMoveMemory( pul + cul, pul, (UsedSize(*pul) + 1) * 4 );
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Member: COnDiskPropertyRecord::LeftCompress, public
|
|
//
|
|
// Synopsis: Moves data from [pul], [cul] dwords down.
|
|
//
|
|
// Arguments: [pul] -- Start of area to move.
|
|
// [cul] -- Count of dwords to move
|
|
// [pulEnd] -- Terminating property. This property will have
|
|
// it's allocated size increased with all the slack
|
|
// from previous properties and have its used size
|
|
// set to 0.
|
|
//
|
|
// Returns: New pointer to pulEnd (which moved down by [cul] bytes).
|
|
//
|
|
// History: 27-Dec-95 KyleP Created.
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
ULONG * COnDiskPropertyRecord::LeftCompress( ULONG * pul, ULONG cul, ULONG * pulEnd )
|
|
{
|
|
//
|
|
// Terminating recursion? Just copy the allocated info. Used size is
|
|
// zero, because data isn't copied.
|
|
//
|
|
|
|
if ( pul == pulEnd )
|
|
{
|
|
pul -= cul;
|
|
|
|
SetAllocatedSize( pul, AllocatedSize(*pulEnd) + cul );
|
|
SetUsedSize( pul, 0 );
|
|
|
|
return pul;
|
|
}
|
|
|
|
//
|
|
// First, move current record.
|
|
//
|
|
|
|
if ( cul > 0 )
|
|
{
|
|
RtlMoveMemory( pul - cul, pul, (UsedSize(*pul) + 1) * 4 );
|
|
pul -= cul;
|
|
}
|
|
|
|
//
|
|
// Adjust allocation size.
|
|
//
|
|
|
|
cul += ( AllocatedSize(*pul) - UsedSize(*pul) );
|
|
SetAllocatedSize( pul, UsedSize(*pul) );
|
|
|
|
return LeftCompress( pul + cul + UsedSize(*pul) + 1, cul, pulEnd );
|
|
}
|