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//+---------------------------------------------------------------------------
//
// Microsoft Windows
// Copyright (C) Microsoft Corporation, 1995 - 2000.
//
// File: RowComp.cxx
//
// Contents: Compares two rows.
//
// Classes: CRowComparator
//
// History: 05-Jun-95 KyleP Created
// 14-JAN-97 KrishnaN Undefined CI_INETSRV and related changes
//
//----------------------------------------------------------------------------
#include <pch.cxx>
#pragma hdrstop
#include <compare.hxx>
#include "rowcomp.hxx"
//+---------------------------------------------------------------------------
//
// Member: CRowComparator::CRowComparator, public
//
// Synopsis: Constructor.
//
// History: 05-Jun-95 KyleP Created.
// 02-Feb-2000 KLam Removed END_CONSTRUCTION
//
//----------------------------------------------------------------------------
CRowComparator::CRowComparator() : _aCmp(0), _aoColumn(0){}
//+---------------------------------------------------------------------------
//
// Member: CRowComparator::~CRowComparator, public
//
// Synopsis: Destructor.
//
// History: 05-Jun-95 KyleP Created.
//
//----------------------------------------------------------------------------
CRowComparator::~CRowComparator(){ delete [] _aDir; delete [] _aCmp; delete [] _aoColumn;}
//+---------------------------------------------------------------------------
//
// Member: CRowComparator::Init, public
//
// Synopsis: Initializes comparator.
//
// Arguments: [sort] -- Sort specification.
// [aBinding] -- Binding filled in here. Must have one
// element per column in sort.
// [aColumnInfo] -- Column metadata
// [cColumnInfo] -- Size of [aColumnInfo]
//
// Returns: Size of buffer needed to satisfy binding.
//
// History: 05-Jun-95 KyleP Created.
//
//----------------------------------------------------------------------------
unsigned CRowComparator::Init( CSort const & sort, DBBINDING * aBinding, DBCOLUMNINFO const * aColumnInfo, DBORDINAL cColumnInfo ){ _cColumn = sort.Count(); _aDir = new int [_cColumn]; _aoColumn = new unsigned [_cColumn]; _aCmp = new FDBCmp [_cColumn];
BYTE * pb = (BYTE *)0 + _cColumn * sizeof(CRowComparator::SColumnStatus);
for ( unsigned i = 0; i < _cColumn; i++ ) { // NTRAID#DB-NTBUG9-84053-2000/07/31-dlee Distributed queries could be faster if ordinals were used to reference columns
for ( DBORDINAL j = 0; j < cColumnInfo; j++ ) { if ( *(CFullPropSpec *)&aColumnInfo[j].columnid == sort.Get(i).GetProperty() ) { RtlZeroMemory(&aBinding[i], sizeof (DBBINDING)); aBinding[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS; aBinding[i].iOrdinal = aColumnInfo[j].iOrdinal; aBinding[i].wType = aColumnInfo[j].wType; // (sizeof (CRowComparator::SColumnStatus) * i ) + offsetof (Status)
aBinding[i].obStatus = (DBBYTEOFFSET) (ULONG_PTR)&((CRowComparator::SColumnStatus *)0)[i].Status; // (sizeof (CRowComparator::SColumnStatus) * i ) + offsetof (Length)
aBinding[i].obLength = (DBBYTEOFFSET) (ULONG_PTR)&((CRowComparator::SColumnStatus *)0)[i].Length;
//
// Invert the meaning of _aCmp[i] for columns that are descending.
//
Win4Assert( QUERY_SORTDESCEND == 1 && QUERY_SORTXDESCEND == 3 );
if ( sort.Get(i).GetOrder() & 1 ) _aDir[i] = -1; else _aDir[i] = 1;
_aCmp[i] = VariantCompare.GetDBComparator( (DBTYPEENUM)aColumnInfo[j].wType );
if ( aColumnInfo[j].wType & DBTYPE_VECTOR ) { _aoColumn[i] = (unsigned)((ULONG_PTR)AlignULONG( pb )); } else if ( aColumnInfo[j].wType & DBTYPE_ARRAY ) { _aoColumn[i] = (unsigned)((ULONG_PTR)AlignULONG( pb )); } else { switch ( aColumnInfo[j].wType ) { case DBTYPE_EMPTY: case DBTYPE_NULL: case DBTYPE_STR: case DBTYPE_BSTR: case DBTYPE_BYTES: _aoColumn[i] = (unsigned)((ULONG_PTR)pb); break;
case DBTYPE_I2: case DBTYPE_UI2: case DBTYPE_BOOL: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignUSHORT( pb )); break;
case DBTYPE_I4: case DBTYPE_UI4: case DBTYPE_ERROR: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignULONG( pb )); break;
case DBTYPE_R4: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignFloat( pb )); break;
case DBTYPE_R8: case DBTYPE_DATE: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignDouble( pb )); break;
case DBTYPE_CY: case DBTYPE_I8: case DBTYPE_UI8: case DBTYPE_VARIANT: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignLONGLONG( pb )); break;
case DBTYPE_GUID: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignGUID( pb )); break;
case DBTYPE_WSTR: _aoColumn[i] = (unsigned)((ULONG_PTR)AlignWCHAR( pb )); break;
default: vqDebugOut(( DEB_WARN, "Can't determine alignment for type %d\n", aColumnInfo[j].wType )); _aoColumn[i] = (unsigned)((ULONG_PTR)pb); break; } }
aBinding[i].obValue = _aoColumn[i]; aBinding[i].cbMaxLen = aColumnInfo[j].ulColumnSize; pb = (BYTE *) ULongToPtr( _aoColumn[i] ) + aColumnInfo[j].ulColumnSize;
break; } }
if ( j == cColumnInfo ) { vqDebugOut(( DEB_ERROR, "Can't bind to sort column.\n" )); Win4Assert( !"Can't bind to sort column." ); THROW( CException(E_FAIL) ); } }
vqDebugOut(( DEB_ITRACE, "CRowComparator: Allocated %d byte buffer for comparisons\n", pb ));
return (unsigned)((ULONG_PTR)pb);}
//+---------------------------------------------------------------------------
//
// Member: CRowComparator::IsLT, public
//
// Synopsis: Less-than comparator
//
// Arguments: [pbRow1] -- Data for row 1.
// [cbRow1] -- Size of [pbRow1]
// [IndexRow1] -- Used to break ties.
// [pbRow2] -- Data for row 2.
// [cbRow2] -- Size of [pbRow2]
// [IndexRow2] -- Used to break ties.
//
// Returns: TRUE of row1 < row2.
//
// History: 05-Jun-95 KyleP Created.
//
//----------------------------------------------------------------------------
BOOL CRowComparator::IsLT( BYTE * pbRow1, ULONG cbRow1, int IndexRow1, BYTE * pbRow2, ULONG cbRow2, int IndexRow2 ){ int iCmp = 0;
CRowComparator::SColumnStatus * aColStatus1 = (CRowComparator::SColumnStatus *)pbRow1; CRowComparator::SColumnStatus * aColStatus2 = (CRowComparator::SColumnStatus *)pbRow2;
for ( unsigned i = 0; i < _cColumn; i++ ) { //
// Verify field was successfully retrieved.
//
if ( FAILED(aColStatus1[i].Status) || FAILED(aColStatus2[i].Status) ) break;
iCmp = _aDir[i] * _aCmp[i]( pbRow1 + _aoColumn[i], (ULONG) aColStatus1[i].Length, // Length will never be 4Gb
pbRow2 + _aoColumn[i], (ULONG)aColStatus2[i].Length ); // Length will never be 4Gb
if ( 0 != iCmp ) break; }
if ( 0 == iCmp ) return( IndexRow1 < IndexRow2 ); else return( iCmp < 0 );}
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