// Copyright (c) 1995-2009 Nokia Corporation and/or its subsidiary(-ies).

 // All rights reserved.

 // This component and the accompanying materials are made available

 // under the terms of the License "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:

 // f32\sfile\sf_pgcompr.h

 // 

 //

 #ifndef __SF_PGCOMPR_H__

 #define __SF_PGCOMPR_H__

 #include <e32base.h>

 #include<f32file.h>

 //#include "sf_std.h"

 #include <f32image.h>

 #include "sf_image.h"

 #include <e32uid.h>

 #include <e32rom.h>

 #include "sf_cache.h"

 const TUint KBytePairPageSize = 4096;

 // Buffer sized for at least 8 compressed pages - a noncompressible page is one byte larger

 const TUint KReadNumberOfPages = 8;

 const TUint KPagesBufferSize = (KBytePairPageSize + 1) * KReadNumberOfPages;

 typedef TUint8* (*TMemoryMoveFunction)(TAny* aTrg,const TAny* aSrc,TInt aLength); 

 struct IndexTableHeader

 	{

 	TInt	iSizeOfData;					// Includes the index and compressed pages

 	TInt	iDecompressedSize;

 	TUint16	iNumberOfPages;

 	};

 // sizeof(IndexTableHeader) returns the wrong value due to rounding/padding, so calculate it

 const TUint KIndexTableHeaderSize = sizeof(TInt) + sizeof(TInt) + sizeof(TUint16);

 NONSHARABLE_CLASS(CBytePairReader) : public CBase

 	{

 public:

 	static CBytePairReader* NewLC(TUint8* aBuffer, TUint32 aLength);

 	CBytePairReader(TUint8* aBuffer, TUint32 aLength);

 	virtual TUint DecompressPagesL(TUint8* aTarget, TInt aLength, TMemoryMoveFunction aMemMoveFn);

 	void GetPageOffsetsL(TInt32 aInitialOffset, TInt& aPageCount, TInt32*& aPageStarts);

 	TUint GetPageL(TUint aPageNum, TUint8* aTarget, TInt aLength, TMemoryMoveFunction aMemMoveFn);		

 	virtual void SeekForwardL(TUint aBytes);

 protected:

 	virtual void ReadInTableL();

 	void ReleaseTable();

 	IndexTableHeader iHeader;

 	TUint16* iIndexTable;

 	TUint8* iNextPage;

 	TUint iBytesLeft;

 	TUint8 iPageBuf[KBytePairPageSize];

 	};

 NONSHARABLE_CLASS(CBytePairFileReader) : public CBytePairReader

 	{

 public:

 	static CBytePairFileReader* NewLC(RFile& aFile);

 	CBytePairFileReader(RFile& aFile);

 	~CBytePairFileReader();

 	virtual TUint DecompressPagesL(TUint8* aTarget, TInt aLength, TMemoryMoveFunction aMemMovefn);

 	virtual void SeekForwardL(TUint aBytes);

 protected:

 	virtual void ReadInTableL();

 	RFile& iFile;

 	TUint8 iBuffer[KPagesBufferSize];

 	};

 #endif // __SF_PGCOMPR_H__