williamr@2: // Copyright (c) 1999-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@2: // under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
williamr@2: // which accompanies this distribution, and is available
williamr@2: // at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: // EZLib: COMPRESSOR.H
williamr@2: // Declaration for Compression class
williamr@2: // 
williamr@2: //
williamr@2: 
williamr@2: #ifndef __EZCOMPRESSOR_H__
williamr@2: #define __EZCOMPRESSOR_H__
williamr@2: 
williamr@2: #include <e32base.h>
williamr@2: #include <ezstream.h>
williamr@2: #include <ezbufman.h>
williamr@2: 
williamr@2: /**
williamr@2: The CEZCompressor class provides in-memory compression functions, including integrity checks of the uncompressed data.
williamr@2: This version of the library supports only one compression method (deflation).  Compression can be done in a single step
williamr@2: (using CompressL()) if the buffers are large enough (for example if an input file is mmap'ed), or can be done by repeated calls
williamr@2: of the DeflateL() function.  The source data is compressed to the target buffer (both source and target contained within 
williamr@2: the buffer manager argument), and various other arguments distinguish the different compression settings.
williamr@2: 
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: class CEZCompressor : public CEZZStream
williamr@2: 	{
williamr@2: public:
williamr@2: 	/** Compression strategy - used to tune the compression algorithm */
williamr@2: 	enum TStrategy
williamr@2: 		{
williamr@2: 		/** Use for normal data */		
williamr@2: 		EDefaultStrategy = Z_DEFAULT_STRATEGY, 
williamr@2: 		
williamr@2: 		/** Force Huffman encoding only (no string match) */
williamr@2: 		EFiltered = Z_FILTERED, 
williamr@2: 		
williamr@2: 		/** Use for data produced by a filter (or predictor) */
williamr@2: 		EHuffmanOnly = Z_HUFFMAN_ONLY
williamr@2: 		};
williamr@2: 
williamr@2: 	/** Compression levels */
williamr@2: 	enum 
williamr@2: 		{
williamr@2: 		EDefaultCompression = Z_DEFAULT_COMPRESSION,
williamr@2: 		ENoCompression = Z_NO_COMPRESSION,
williamr@2: 		EBestSpeed = Z_BEST_SPEED,
williamr@2: 		EBestCompression = Z_BEST_COMPRESSION
williamr@2: 		};
williamr@2: 
williamr@2: 	/** Window Bits - the base two logarithm of the window size (the size of the history buffer) */
williamr@2: 	enum
williamr@2: 		{
williamr@2: 		EMaxWBits = MAX_WBITS
williamr@2: 		};
williamr@2: 
williamr@2: 	/** Memory level - specifies how much memory should be allocated for the internal compression state */
williamr@2: 	enum
williamr@2: 		{
williamr@2: 		EDefMemLevel = MAX_MEM_LEVEL
williamr@2: 		};
williamr@2: 
williamr@2: 	/** Compression panic values */
williamr@2: 	enum
williamr@2: 		{
williamr@2: 		EDeflateInitlialiserError = EUnexpected + 1,
williamr@2: 		EDeflateTerminated
williamr@2: 		};
williamr@2: 
williamr@2: 	public:
williamr@2: 		~CEZCompressor();
williamr@2: 
williamr@2: 		IMPORT_C static CEZCompressor* NewLC(MEZBufferManager& aInit, TInt aLevel = EDefaultCompression,
williamr@2: 			TInt aWindowBits = EMaxWBits, TInt aMemLevel = EDefMemLevel, TStrategy aStrategy = EDefaultStrategy);
williamr@2: 		IMPORT_C static CEZCompressor* NewL(MEZBufferManager& aInit, TInt aLevel = EDefaultCompression,
williamr@2: 			TInt aWindowBits = EMaxWBits, TInt aMemLevel = EDefMemLevel, TStrategy aStrategy = EDefaultStrategy);
williamr@2: 		IMPORT_C static CEZCompressor* NewLC(MEZBufferManager& aInit, const TDesC8 &aDictionary, 
williamr@2: 			TInt aLevel = EDefaultCompression, TInt aWindowBits = EMaxWBits, TInt aMemLevel = EDefMemLevel, 
williamr@2: 			TStrategy aStrategy = EDefaultStrategy);
williamr@2: 		IMPORT_C static CEZCompressor* NewL(MEZBufferManager& aInit, const TDesC8 &aDictionary,  
williamr@2: 			TInt aLevel = EDefaultCompression, TInt aWindowBits = EMaxWBits, TInt aMemLevel = EDefMemLevel, 
williamr@2: 			TStrategy aStrategy = EDefaultStrategy);
williamr@2: 
williamr@2: 		IMPORT_C void ResetL(MEZBufferManager& aInit);
williamr@2: 
williamr@2: 		IMPORT_C TBool DeflateL();
williamr@2: 
williamr@2: 		IMPORT_C static void CompressL(TDes8 &aDestination, const TDesC8 &aSource, TInt aLevel = EDefaultCompression);
williamr@2: 
williamr@2: 	private:
williamr@2: 		enum TDeflationState
williamr@2: 			{
williamr@2: 			ENoFlush,
williamr@2: 			EFinish,
williamr@2: 			EFinalize,
williamr@2: 			ETerminated
williamr@2: 			};
williamr@2: 
williamr@2: 	private:
williamr@2: 		CEZCompressor(MEZBufferManager* aInit);
williamr@2: 		void ConstructL(TInt aLevel, const TUint8* aDictionary, TInt aLength, TInt aWindowBits, TInt aMemLevel, TStrategy aStrategy);
williamr@2: 		void ConstructL(TInt aLevel, TInt aWindowBits, TInt aMemLevel, TStrategy aStrategy);
williamr@2: 
williamr@2: 	private:
williamr@2: 		MEZBufferManager* iBufferInit;
williamr@2: 		TDeflationState iDeflationState;
williamr@2: 	};
williamr@2: 
williamr@2: #endif