1 /*

     2 * Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 * e32tools\petran\Szip\deflate.h

    16 *

    17 */

    18 

    19 

    20 #ifndef __DECODE_H__

    21 #define __DECODE_H__

    22 

    23 #include "huffman.h"

    24 #include <e32base.h>

    25 

    26 // deflation constants

    27 const TInt KDeflateLengthMag=8;

    28 const TInt KDeflateDistanceMag=12;

    29 //

    30 const TInt KDeflateMinLength=3;

    31 const TInt KDeflateMaxLength=KDeflateMinLength-1 + (1<<KDeflateLengthMag);

    32 const TInt KDeflateMaxDistance=(1<<KDeflateDistanceMag);

    33 const TInt KDeflateDistCodeBase=0x200;

    34 // hashing

    35 const TUint KDeflateHashMultiplier=0xAC4B9B19u;

    36 const TInt KDeflateHashShift=24;

    37 

    38 class TEncoding

    39 	{

    40 public:

    41 	enum {ELiterals=256,ELengths=(KDeflateLengthMag-1)*4,ESpecials=1,EDistances=(KDeflateDistanceMag-1)*4};

    42 	enum {ELitLens=ELiterals+ELengths+ESpecials};

    43 	enum {EEos=ELiterals+ELengths};

    44 public:

    45 	TUint32 iLitLen[ELitLens];

    46 	TUint32 iDistance[EDistances];

    47 	};

    48 

    49 const TInt KDeflationCodes=TEncoding::ELitLens+TEncoding::EDistances;

    50 

    51 class CInflater

    52 	{

    53 public:

    54 	enum {EBufSize = 0x800, ESafetyZone=8};

    55 public:

    56 	static CInflater* NewLC(TBitInput& aInput);

    57 	~CInflater();

    58 //

    59 	TInt ReadL(TUint8* aBuffer,TInt aLength);

    60 	TInt SkipL(TInt aLength);

    61 private:

    62 	CInflater(TBitInput& aInput);

    63 	void ConstructL();

    64 	void InitL();

    65 	TInt InflateL();

    66 private:

    67 	TBitInput* iBits;

    68 	const TUint8* iRptr;			// partial segment

    69 	TInt iLen;

    70 	const TUint8* iAvail;			// available data

    71 	const TUint8* iLimit;

    72 	TEncoding* iEncoding;

    73 	TUint8* iOut;					// circular buffer for distance matches

    74 	TUint8 iHuff[EBufSize+ESafetyZone];			// huffman data

    75 	};

    76 

    77 void DeflateL(const TUint8* aBuf, TInt aLength, TBitOutput& aOutput);

    78 

    79 #endif

    80