// Copyright (c) 2008-2009 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:

//

#ifndef __SQLSRVBLOB_H__

#define __SQLSRVBLOB_H__

#include <s32buf.h>

//Forward declarations

struct sqlite3_blob;

/**

Stream buffer class with no intermediate buffering capabilities.

The primary purpose of this class is:

 - to read/write from/to a blob column using sqlite3_blob_read()/sqlite3_blob_write() SQLite functions;

 - to serve as an IPC buffer for streaming the blob content from/to the client side dll;

The class overrides the following virtual MStreamBuf functions:

 - DoRelease();

 - DoSynchL();

 - DoReadL();

 - DoWriteL();

 - DoSeekL();

@internalComponent

*/

NONSHARABLE_CLASS(HBlobBuf) : public MStreamBuf

	{

public: 

	enum TMode 

		{

		EReadOnly,

		EReadWrite

		};

public: 

	static HBlobBuf* NewL(sqlite3* aDb, const TDesC8& aDbName, const TDesC8&  aTableName, const TDesC8&  aColumnName, TInt64 aRowId, TMode aMode);

private:

	HBlobBuf();

	void ConstructL(sqlite3* aDb, const TDesC8& aDbName, const TDesC8& aTableName, const TDesC8& aColumnName, TInt64 aRowId, TMode aMode);

	virtual void DoRelease();

	virtual void DoSynchL();

	virtual TInt DoReadL(TAny* aPtr, TInt aMaxLength);

	virtual void DoWriteL(const TAny* aPtr, TInt aLength);

	virtual TStreamPos DoSeekL(MStreamBuf::TMark aMark, TStreamLocation aLocation, TInt aOffset);

	sqlite3_blob* BlobHandleL();

private:

	sqlite3_blob*	iBlobHandle;

	TInt 			iBlobSize;

	TInt			iWrPos;

	TInt			iRdPos;

	};

#endif//__SQLSRVBLOB_H__