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

     2 // All rights reserved.

     3 // This component and the accompanying materials are made available

     4 // under the terms of "Eclipse Public License v1.0"

     5 // which accompanies this distribution, and is available

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

     7 //

     8 // Initial Contributors:

     9 // Nokia Corporation - initial contribution.

    10 //

    11 // Contributors:

    12 //

    13 // Description:

    14 // e32tools\petran\Szip\deflate.h

    15 // 

    16 //

    17 

    18 #ifndef __DECODE_H__

    19 #define __DECODE_H__

    20 

    21 #include "huffman.h"

    22 #include <e32base.h>

    23 

    24 // deflation constants

    25 const TInt KDeflateLengthMag=8;

    26 const TInt KDeflateDistanceMag=12;

    27 //

    28 const TInt KDeflateMinLength=3;

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

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

    31 const TInt KDeflateDistCodeBase=0x200;

    32 // hashing

    33 const TUint KDeflateHashMultiplier=0xAC4B9B19u;

    34 const TInt KDeflateHashShift=24;

    35 

    36 class TEncoding

    37 	{

    38 public:

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

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

    41 	enum {EEos=ELiterals+ELengths};

    42 public:

    43 	TUint32 iLitLen[ELitLens];

    44 	TUint32 iDistance[EDistances];

    45 	};

    46 

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

    48 

    49 class CInflater

    50 	{

    51 public:

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

    53 public:

    54 	static CInflater* NewLC(TBitInput& aInput);

    55 	~CInflater();

    56 //

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

    58 	TInt SkipL(TInt aLength);

    59 private:

    60 	CInflater(TBitInput& aInput);

    61 	void ConstructL();

    62 	void InitL();

    63 	TInt InflateL();

    64 private:

    65 	TBitInput* iBits;

    66 	const TUint8* iRptr;			// partial segment

    67 	TInt iLen;

    68 	const TUint8* iAvail;			// available data

    69 	const TUint8* iLimit;

    70 	TEncoding* iEncoding;

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

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

    73 	};

    74 

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

    76 

    77 #endif

    78