--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/toolsandutils/e32tools/elf2e32/source/huffman.h Tue Feb 02 01:39:43 2010 +0200
@@ -0,0 +1,225 @@
+// Copyright (c) 2004-2009 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:
+// Huffman Class for deflate and inflate
+// @internalComponent
+// @released
+//
+//
+
+#ifndef __HUFFMAN_H__
+#define __HUFFMAN_H__
+
+#include "e32defwrap.h"
+#include <fstream>
+
+/**
+class Bit Output stream
+@internalComponent
+@released
+*/
+class TBitOutput
+{
+ public:
+ TBitOutput();
+ TBitOutput(TUint8* aBuf,TInt aSize);
+ inline void Set(TUint8* aBuf,TInt aSize);
+ inline const TUint8* Ptr() const;
+ inline TInt BufferedBits() const;
+ void WriteL(TUint aValue, TInt aLength);
+ void HuffmanL(TUint aHuffCode);
+ void PadL(TUint aPadding);
+ private:
+ void DoWriteL(TUint aBits, TInt aSize);
+ virtual void OverflowL();
+ private:
+ TUint iCode; // code in production
+ TInt iBits;
+ TUint8* iPtr;
+ TUint8* iEnd;
+};
+
+/*
+Set the memory buffer to use for output
+
+Data will be written to this buffer until it is full, at which point OverflowL() will be
+called. This should handle the data and then can Set() again to reset the buffer for further
+output.
+
+@param "TUint8* aBuf" The buffer for output
+@param "TInt aSize" The size of the buffer in bytes
+@internalComponent
+@released
+*/
+inline void TBitOutput::Set(TUint8* aBuf,TInt aSize)
+{
+ iPtr=aBuf;
+ iEnd=aBuf+aSize;
+}
+
+/*
+Get the current write position in the output buffer
+
+In conjunction with the address of the buffer, which should be known to the caller, this
+describes the data in the bitstream.
+@internalComponent
+@released
+*/
+inline const TUint8* TBitOutput::Ptr() const
+{
+ return iPtr;
+}
+
+/*
+Get the number of bits that are buffered
+
+This reports the number of bits that have not yet been written into the output buffer.It will
+always lie in the range 0..7. Use PadL() to pad the data out to the next byte and write it to
+the buffer.
+@internalComponent
+@released
+*/
+inline TInt TBitOutput::BufferedBits() const
+{
+ return iBits+8;
+}
+
+/**
+This class is derived from TBitOutput
+@internalComponent
+@released
+*/
+class TFileOutput : public TBitOutput
+{
+ enum {KBufSize=0x1000};
+ public:
+ TFileOutput(std::ofstream & os);
+ void FlushL();
+ TUint32 iDataCount;
+ private:
+ void OverflowL();
+ private:
+ std::ofstream & iOutStream;
+ TUint8 iBuf[KBufSize];
+};
+
+/**
+Class for Bit input stream.
+Good for reading bit streams for packed, compressed or huffman data algorithms.
+@since 8.0
+@library euser.lib
+@internalComponent
+@released
+*/
+class TBitInput
+{
+ public:
+ TBitInput();
+ TBitInput(const TUint8* aPtr, TInt aLength, TInt aOffset=0);
+ void Set(const TUint8* aPtr, TInt aLength, TInt aOffset=0);
+ TUint ReadL();
+ TUint ReadL(TInt aSize);
+ TUint HuffmanL(const TUint32* aTree);
+ private:
+ virtual void UnderflowL();
+ private:
+ TInt iCount;
+ TUint iBits;
+ TInt iRemain;
+ const TUint32* iPtr;
+};
+
+/**
+Class derived from TBitInput
+@internalComponent
+@released
+*/
+class TFileInput : public TBitInput
+{
+ public:
+ TFileInput(unsigned char* source,int size);
+ ~TFileInput();
+ private:
+ void UnderflowL();
+ private:
+ TUint8* iReadBuf;
+ TInt iSize;
+};
+
+/*
+Class for Huffman code toolkit.
+
+This class builds a huffman encoding from a frequency table and builds a decoding tree from a
+code-lengths table.
+
+The encoding generated is based on the rule that given two symbols s1 and s2, with code
+length l1 and l2, and huffman codes h1 and h2:
+ if l1<l2 then h1<h2 when compared lexicographically
+ if l1==l2 and s1<s2 then h1<h2 ditto
+
+This allows the encoding to be stored compactly as a table of code lengths
+
+@since 8.0
+@library euser.lib
+@internalComponent
+@released
+*/
+class Huffman
+{
+ public:
+ enum {KMaxCodeLength=27};
+ enum {KMetaCodes=KMaxCodeLength+1};
+ enum {KMaxCodes=0x8000};
+ public:
+ static void HuffmanL(const TUint32 aFrequency[],TInt aNumCodes,TUint32 aHuffman[]);
+ static void Encoding(const TUint32 aHuffman[],TInt aNumCodes,TUint32 aEncodeTable[]);
+ static TBool IsValid(const TUint32 aHuffman[],TInt aNumCodes);
+ static void ExternalizeL(TBitOutput& aOutput,const TUint32 aHuffman[],TInt aNumCodes);
+ static void Decoding(const TUint32 aHuffman[],TInt aNumCodes,TUint32 aDecodeTree[],TInt aSymbolBase=0);
+ static void InternalizeL(TBitInput& aInput,TUint32 aHuffman[],TInt aNumCodes);
+};
+
+// local definitions used for Huffman code generation
+typedef TUint16 THuff; /** @internal */
+const THuff KLeaf=0x8000; /** @internal */
+struct TNode
+/** @internal */
+{
+ TUint iCount;
+ THuff iLeft;
+ THuff iRight;
+};
+
+const TInt KDeflateLengthMag=8;
+const TInt KDeflateDistanceMag=12;
+
+/**
+class for TEncoding
+@internalComponent
+@released
+*/
+class TEncoding
+{
+ public:
+ enum {ELiterals=256,ELengths=(KDeflateLengthMag-1)*4,ESpecials=1,EDistances=(KDeflateDistanceMag-1)*4};
+ enum {ELitLens=ELiterals+ELengths+ESpecials};
+ enum {EEos=ELiterals+ELengths};
+ public:
+ TUint32 iLitLen[ELitLens];
+ TUint32 iDistance[EDistances];
+};
+
+const TInt KDeflationCodes=TEncoding::ELitLens+TEncoding::EDistances;
+
+#endif
+