--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/persistentstorage/dbms/sdbms/SD_CURS.CPP	Fri Jan 22 11:06:30 2010 +0200
@@ -0,0 +1,442 @@
+// Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of "Eclipse Public License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.eclipse.org/legal/epl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+// DBMS server proxy cursor
+// 
+//
+
+#include "SD_STD.H"
+
+const TDbBlobId KUnknownBlobId=~0u;
+
+// Class HDbsColumns
+
+class HDbsColumns
+	{
+public:
+	static HDbsColumns* NewL(TInt aCount);
+	inline void Set(const TUint8* aPtr);
+	inline TPtr8 Ptr();
+	inline TInt Count() const;
+	inline TDbColType Type(TDbColNo aCol) const;
+	void Check(TDbColNo aCol) const;
+private:
+	inline HDbsColumns(TInt aCount);
+private:
+	TInt iCount;
+	TUint8 iType[1];
+	};
+
+inline HDbsColumns::HDbsColumns(TInt aCount)
+	:iCount(aCount)
+	{}
+inline void HDbsColumns::Set(const TUint8* aPtr)
+	{Mem::Copy(iType,aPtr,iCount);}
+inline TPtr8 HDbsColumns::Ptr()
+	{return TPtr8(iType,iCount);}
+inline TInt HDbsColumns::Count() const
+	{return iCount;}
+inline TDbColType HDbsColumns::Type(TDbColNo aCol) const
+	{__DEBUG(Check(aCol));return TDbColType(iType[aCol-1]);}
+
+HDbsColumns* HDbsColumns::NewL(TInt aCount)
+	{
+	return new(User::AllocL(_FOFF(HDbsColumns,iType[aCount]))) HDbsColumns(aCount);
+	}
+
+void HDbsColumns::Check(TDbColNo aColNo) const
+	{
+	__ASSERT_ALWAYS(aColNo>0&&aColNo<=iCount,Panic(EDbsInvalidColumn));
+	}
+
+// Class CDbsCursor
+
+CDbsCursor::CDbsCursor()
+	:iState(EAtBeginning)
+	{}
+
+CDbsCursor* CDbsCursor::NewL(const RDbsObject& aDbs,TDbsFunction aFunction,TIpcArgs& aArgs)
+	{
+	CDbsCursor* self=new(ELeave) CDbsCursor;
+	CleanupStack::PushL(self);
+	self->ConstructL(aDbs,aFunction,aArgs);
+	CleanupStack::Pop();
+	return self;
+	}
+
+void CDbsCursor::ConstructL(const RDbsObject& aDbs,TDbsFunction aFunction,TIpcArgs& aArgs)
+//
+// construct a cursor from the supplied parameters
+// Retrieve the column types, in one pass if possible
+//
+	{
+	TPckgBuf<TDbsColumns> cols;
+	aArgs.Set(3,&cols);
+	iObject.OpenL(aDbs,aFunction,aArgs);
+	iColumns=HDbsColumns::NewL(cols().iCount);
+	if (cols().iCount<=cols().EMax)
+		iColumns->Set(cols().iData);	// we have the column types
+	else
+		{	// too many for the fixed buffer, make a second call to get the columns
+		TPtr8 ptr=iColumns->Ptr();
+		aArgs.Set(3,&ptr);
+		iObject.SendReceiveL(EDbsCursorColumnTypes,aArgs);
+		}
+	}
+
+CDbsCursor::~CDbsCursor()
+	{
+	iObject.Close();
+	delete iColumns;
+	iRow.Close();
+	}
+
+TDbColType CDbsCursor::Type(TDbColNo aCol) const
+	{
+	iColumns->Check(aCol);
+	return iColumns->Type(aCol);
+	}
+
+void CDbsCursor::Reset()
+	{
+	iState=EAtBeginning;
+	iObject.SendReceive(EDbsCursorReset);
+	}
+
+TBool CDbsCursor::EvaluateL()
+	{
+	iState=EUnknown;
+	return iObject.SendReceiveL(EDbsCursorEvaluate);
+	}
+
+void CDbsCursor::Evaluate(TRequestStatus& aStatus)
+	{
+	iState=EUnknown;
+	iObject.SendReceive(EDbsCursorEvaluate,aStatus);
+	}
+
+TBool CDbsCursor::Unevaluated()
+	{
+	return iObject.SendReceive(EDbsCursorUnevaluated);
+	}
+
+void CDbsCursor::SetIndexL(const TDesC* anIndex)
+	{
+	iObject.SendReceiveL(EDbsCursorSetIndex,TIpcArgs(anIndex));
+	iState=EAtBeginning;
+	}
+
+TBool CDbsCursor::SeekL(const TDbLookupKey& aKey,RDbTable::TComparison aComparison)
+	{
+	TPtrC8 key(TDbsParam::PrepareLC(aKey));
+	iState=EUnknown;
+	TBool found=iObject.SendReceiveL(EDbsCursorSeek,TIpcArgs(&key,key.Length(),aComparison));
+	CleanupStack::PopAndDestroy();	// key
+	if (found)
+		iState=EAtRow;
+	return found;
+	}
+
+TBool CDbsCursor::AtBeginning()
+	{
+	if (iState==EUnknown && iObject.SendReceive(EDbsCursorAtBeginning)>0)
+		iState=EAtBeginning;
+	return iState==EAtBeginning;
+	}
+
+TBool CDbsCursor::AtEnd()
+	{
+	if (iState==EUnknown && iObject.SendReceive(EDbsCursorAtEnd)>0)
+		iState=EAtEnd;
+	return iState==EAtEnd;
+	}
+
+TBool CDbsCursor::AtRow()
+	{
+	if (iState==EUnknown && iObject.SendReceive(EDbsCursorAtRow)>0)
+		iState=EAtRow;
+	return iState>=EAtRow;
+	}
+
+TInt CDbsCursor::CountL(RDbRowSet::TAccuracy aAccuracy)
+//
+// valid response is >=0 + undefined (==-1)
+// server returns +1 for non-error conditions
+//
+	{
+	return iObject.SendReceiveL(EDbsCursorCount,TIpcArgs(aAccuracy))-1;
+	}
+
+TBool CDbsCursor::GotoL(RDbRowSet::TPosition aPosition)
+	{
+	TBool atrow=RetrieveL(EDbsCursorGotoPos,aPosition);
+	if (atrow)
+		iState=ERetrieve;
+	else
+		{
+		switch (aPosition)
+			{
+		default:
+			__ASSERT(0);
+		case RDbRowSet::EEnd:
+		case RDbRowSet::EFirst:
+		case RDbRowSet::ENext:
+			iState=EAtEnd;
+			break;
+		case RDbRowSet::EBeginning:
+		case RDbRowSet::ELast:
+		case RDbRowSet::EPrevious:
+			iState=EAtBeginning;
+			break;
+			}
+		}
+	return atrow;
+	}
+
+void CDbsCursor::Bookmark(TDbBookmark::TMark& aMark)
+	{
+	TPckg<TDbBookmark::TMark> pckg(aMark);
+	iObject.SendReceive(EDbsCursorBookmark,TIpcArgs(TIpcArgs::ENothing,TIpcArgs::ENothing,TIpcArgs::ENothing,&pckg));
+	}
+
+void CDbsCursor::GotoL(const TDbBookmark::TMark& aMark)
+	{
+	TPckgC<TDbBookmark::TMark> pckg(aMark);
+	iState=EUnknown;
+	iObject.SendReceiveL(EDbsCursorGotoBookmark,TIpcArgs(&pckg));
+	}
+
+LOCAL_C void CancelCursor(TAny* aPtr)
+	{
+	STATIC_CAST(CDbCursor*,aPtr)->Cancel();
+	}
+
+TBool CDbsCursor::RetrieveL(TDbsFunction aFunction,TInt aArg0)
+//
+// Read the row buffer
+//
+	{
+	iState=EUnknown;
+	TInt size;
+	for (;;)
+		{
+		TInt max=iRow.MaxSize();
+		TPtr8 row((TUint8*)iRow.First(),max);
+		size=iObject.SendReceiveL(aFunction,TIpcArgs(aArg0,TIpcArgs::ENothing,max,&row))-1;
+		if (size<0)
+			return EFalse;		// no row to retrieve
+		if (size<=max)
+			break;
+		// didn't fit! Grow the buffer
+		if (aFunction!=EDbsCursorRetrieveRow)
+			{
+			CleanupStack::PushL(TCleanupItem(CancelCursor,this));	// in case this goes wrong!
+			aFunction=EDbsCursorRetrieveRow;
+			}
+		iRow.GrowL(size);
+		}
+	iRow.SetSize(size);
+	if (aFunction==EDbsCursorRetrieveRow)
+		CleanupStack::Pop();
+	return ETrue;
+	}
+
+void CDbsCursor::GetL()
+	{
+	if (iState!=ERetrieve)
+		RetrieveL(EDbsCursorGet);
+	iState=ERead;
+	}
+
+void CDbsCursor::InsertL(TInsert aClearRow)
+	{
+	RetrieveL(EDbsCursorInsert,aClearRow);
+	iState=EWrite;
+	iChangedBlob=EFalse;
+	}
+
+void CDbsCursor::UpdateL()
+	{
+	RetrieveL(EDbsCursorUpdate);
+	iState=EWrite;
+	iChangedBlob=EFalse;
+	}
+
+void CDbsCursor::Cancel()
+	{
+	if (iState==EUnknown || iState==EWrite)
+		iObject.SendReceive(EDbsCursorCancel);
+	}
+
+void CDbsCursor::PutL()
+	{
+	TInt size=iRow.Size();
+	TPtrC8 row((const TUint8*)iRow.First(),size);
+	iObject.SendReceiveL(EDbsCursorPut,TIpcArgs(&row,size,iChangedBlob));// if iChangedBlob false, server can optimize put
+	iState=ERead;		// we can still look at the row we put
+	}
+
+void CDbsCursor::DeleteL()
+	{
+	iState=EUnknown;
+	iObject.SendReceiveL(EDbsCursorDelete);
+	}
+
+TInt CDbsCursor::ColumnCount()
+	{
+	return iColumns->Count();
+	}
+
+void CDbsCursor::ColumnsL(CDbColSet& aColSet)
+//
+// optimise the retreival of all columns
+//
+	{
+	TIpcArgs m;
+	RReadStream in(HDbsBuf::NewLC(iObject,EDbsCursorColumns,m));
+	in>>aColSet;
+	CleanupStack::PopAndDestroy();	// buffer
+	}
+
+void CDbsCursor::ColumnDef(TDbCol& aCol,TDbColNo aColNo)
+	{
+	TPckg<TDbCol> pckg(aCol);
+	iColumns->Check(aColNo);
+	iObject.SendReceive(EDbsCursorColumnDef,TIpcArgs(aColNo,TIpcArgs::ENothing,TIpcArgs::ENothing,&pckg));
+	}
+
+TDbColType CDbsCursor::ColumnType(TDbColNo aCol)
+	{
+	return Type(aCol);
+	}
+
+RDbRow* CDbsCursor::RowBuffer()
+//
+// Invoked by the server-- should not be called
+//
+	{
+	__ASSERT(0);
+	return 0;
+	}
+
+TDbColumnC CDbsCursor::ColumnC(TDbColNo aCol)
+//
+// check row is valid for extraction
+//
+	{
+	__ASSERT_ALWAYS(iState>=ERead,Panic(EDbsNoRowData));
+	return TDbColumnC(iRow,aCol);
+	}
+
+TDbColumn CDbsCursor::Column(TDbColNo aCol)
+//
+// check row is valid for writing
+//
+	{
+	__ASSERT_ALWAYS(iState==EWrite,Panic(EDbsNotInUpdate));
+	return TDbColumn(iRow,aCol);
+	}
+
+void CDbsCursor::ReplaceBlobL(TDbColumn& aCol)
+//
+// We no longer know what the shape of a blob is, mark it as "unknown"
+//
+	{
+	iChangedBlob=ETrue;
+	aCol.SetBlobL(KUnknownBlobId);
+	}
+
+void CDbsCursor::SetNullL(TDbColNo aCol)
+//
+// Make the column Null
+//
+	{
+	TDbColumn col=Column(aCol);
+	if (!TDbCol::IsLong(Type(aCol)))
+		col.SetNull();
+	else if (!TDbColumnC(col).IsNull())
+		{
+		ReplaceBlobL(col);
+		iObject.SendReceiveL(EDbsCursorSetNull,TIpcArgs(aCol));
+		}
+	}
+
+TInt CDbsCursor::ColumnSize(TDbColNo aCol)
+	{
+	TDbColumnC col(ColumnC(aCol));
+	if (!TDbCol::IsLong(Type(aCol)))
+		return col.Size();
+	TInt size=col.Blob().Size();
+	if (size>=0)
+		return size;
+	// unknown size, so ask the server
+	return iObject.SendReceive(EDbsCursorColumnSize,TIpcArgs(aCol));
+	}
+
+MStreamBuf* CDbsCursor::ColumnSourceL(TDbColNo aCol)
+	{
+	TDbColumnC col(ColumnC(aCol));
+	if (!TDbCol::IsLong(iColumns->Type(aCol)))
+		return HDbsReadBuf::NewL(col.PtrC8());
+	// blobs
+	const TDbBlob& blob=col.Blob();
+	if (blob.IsInline())
+		return HDbsReadBuf::NewL(blob.PtrC8());
+	// get it from the server
+	TIpcArgs args(aCol);
+	return HDbsBuf::NewL(iObject,EDbsCursorColumnSource,args);
+	}
+
+MStreamBuf* CDbsCursor::ColumnSinkL(TDbColNo aCol)
+	{
+	TDbColumn col(Column(aCol));
+	ReplaceBlobL(col);
+	TIpcArgs args(aCol);
+	return HDbsBuf::NewL(iObject,EDbsCursorColumnSink,args);
+	}
+
+CDbRowConstraint* CDbsCursor::OpenConstraintL(const TDbQuery& aQuery)
+	{
+	const TDesC& des = aQuery.Query();
+	CDbsConstraint* c=new(ELeave) CDbsConstraint();
+	CleanupStack::PushL(c);
+	c->iObject.OpenL(iObject,EDbsCursorOpenConstraint,TIpcArgs(&des,aQuery.Comparison()));
+	CleanupStack::Pop();
+	return c;
+	}
+
+TBool CDbsCursor::MatchL(CDbRowConstraint& aConstraint)
+	{
+	TInt handle = STATIC_CAST(CDbsConstraint&,aConstraint).iObject.Handle();
+	return iObject.SendReceiveL(EDbsCursorMatch,TIpcArgs(handle));
+	}
+
+TInt CDbsCursor::FindL(RDbRowSet::TDirection aDirection,const TDbQuery& aCriteria)
+//
+// Server returns result-KErrNotFound, to ensure non-leaving on not found
+//
+	{
+	const TDesC& des = aCriteria.Query();
+	iState=EUnknown;
+	TInt f=iObject.SendReceiveL(EDbsCursorFind,TIpcArgs(&des,aCriteria.Comparison(),aDirection))+KErrNotFound;
+	if (f>=0)
+		iState=EAtRow;
+	return f;
+	}
+
+// Class CDbsConstraint
+
+CDbsConstraint::~CDbsConstraint()
+	{
+	iObject.Close();
+	}