--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/persistentstorage/store/INC/S32UCMP.H Fri Jan 22 11:06:30 2010 +0200
@@ -0,0 +1,355 @@
+// Copyright (c) 1998-2009 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:
+// Header for the Standard Compression Scheme for Unicode.
+// This code is compiled only in the Unicode build.
+//
+//
+
+#ifndef __S32UCMP_H__
+#define __S32UCMP_H__ 1
+
+#ifdef _UNICODE
+
+#include <e32std.h>
+#include <s32mem.h>
+
+/**
+ * @publishedAll
+ * @released
+ */
+class TUnicodeCompressionState
+ {
+ public:
+ TUnicodeCompressionState();
+ void Reset();
+ static TInt StaticWindowIndex(TUint16 aCode);
+ static TInt DynamicWindowOffsetIndex(TUint16 aCode);
+ static TUint32 DynamicWindowBase(TInt aOffsetIndex);
+ static TBool EncodeAsIs(TUint16 aCode);
+
+ enum TPanic
+ {
+ EUnhandledByte, // expander code fails to handle all possible byte codes
+ ENotUnicode, // expander can't handle Unicode values outside range 0x0..0x10FFFF;
+ // that is, 16-bit codes plus 32-bit codes that can be expressed using
+ // 16-bit surrogates
+ EOutputBufferOverflow // output buffer is not big enough
+ };
+
+ static void Panic(TPanic aPanic);
+
+ protected:
+
+ enum
+ {
+ EStaticWindows = 8,
+ EDynamicWindows = 8,
+ ESpecialBases = 7
+ };
+
+ TBool iUnicodeMode; // TRUE if in Unicode mode as opposed to single-byte mode
+ TUint32 iActiveWindowBase; // base of the active window - bases are 32-bit because they
+ // can be set to the surrogate area, which represents codes
+ // from 0x00010000 to 0x0010FFFF - planes 1-16 of ISO-10646.
+ static const TUint32 iStaticWindow[EStaticWindows]; // bases of the static windows
+ static const TUint32 iDynamicWindowDefault[EDynamicWindows]; // default bases of the dynamic windows
+ static const TUint16 iSpecialBase[ESpecialBases]; // bases for window offsets F9..FF
+
+ TUint32 iDynamicWindow[EDynamicWindows]; // bases of the dynamic windows
+ TInt iUnicodeWords; // Unicode words processed; read by compressor, written by expander
+ TInt iMaxUnicodeWords; // maximum number of Unicode words to read or write
+ TInt iCompressedBytes; // compressed bytes processed: read by expander, written by compressor
+ TInt iMaxCompressedBytes; // maximum number of compressed bytes to read or write
+ };
+
+/**
+ * @publishedAll
+ * @released
+ */
+class MUnicodeSource
+ {
+ public:
+ virtual TUint16 ReadUnicodeValueL() = 0;
+ };
+
+/**
+ * @publishedAll
+ * @released
+ A class to read Unicode values directly from memory.
+ */
+class TMemoryUnicodeSource: public MUnicodeSource
+ {
+ public:
+ inline TMemoryUnicodeSource(const TUint16* aPtr);
+ inline TUint16 ReadUnicodeValueL();
+
+ private:
+ const TUint16* iPtr;
+ };
+
+/**
+ * @publishedAll
+ * @released
+ A class to read Unicode values from a stream built on a memory object.
+ */
+class TMemoryStreamUnicodeSource: public MUnicodeSource
+ {
+ public:
+ inline TMemoryStreamUnicodeSource(RReadStream& aStream);
+ inline TUint16 ReadUnicodeValueL();
+
+ private:
+ RReadStream& iStream;
+ };
+
+/**
+ * @publishedAll
+ * @released
+ */
+class MUnicodeSink
+ {
+ public:
+ virtual void WriteUnicodeValueL(TUint16 aValue) = 0;
+ };
+
+/**
+ * @publishedAll
+ * @released
+ A class to write Unicode values directly to memory.
+ */
+class TMemoryUnicodeSink: public MUnicodeSink
+ {
+ public:
+ inline TMemoryUnicodeSink(TUint16* aPtr);
+ inline void WriteUnicodeValueL(TUint16 aValue);
+
+ private:
+ TUint16* iPtr;
+ };
+
+/**
+ * @publishedAll
+ * @released
+ A class to write Unicode values to a stream built on a memory object.
+ */
+class TMemoryStreamUnicodeSink: public MUnicodeSink
+ {
+ public:
+ inline TMemoryStreamUnicodeSink(RWriteStream& aStream);
+ inline void WriteUnicodeValueL(TUint16 aValue);
+
+ private:
+ RWriteStream& iStream;
+ };
+
+/**
+ * @publishedAll
+ * @released
+
+A class to hold functions to compress text using the Standard Compression Scheme for Unicode.
+
+A note on error handling and leaving.
+
+Although all the public functions except the constructor can leave, it is possible to guarantee success: that is,
+guarantee that a call will not leave, and that compression will be completed. To do this, (i) supply a MUnicodeSource
+object with a non-leaving ReadUnicodeValueL function, such as a TMemoryUnicodeSource; (ii) write output to a
+RWriteStream with a non-leaving WriteL function, or to a buffer that you already know to be big enough, which can be
+found out using CompressedSizeL.
+
+This guarantee of success is particularly useful when compressing from one memory buffer to another.
+*/
+class TUnicodeCompressor: public TUnicodeCompressionState
+ {
+ public:
+ IMPORT_C TUnicodeCompressor();
+ IMPORT_C void CompressL(RWriteStream& aOutput,MUnicodeSource& aInput,
+ TInt aMaxOutputBytes = KMaxTInt,TInt aMaxInputWords = KMaxTInt,
+ TInt* aOutputBytes = NULL,TInt* aInputWords = NULL);
+ IMPORT_C void CompressL(TUint8* aOutput,MUnicodeSource& aInput,
+ TInt aMaxOutputBytes = KMaxTInt,TInt aMaxInputWords = KMaxTInt,
+ TInt* aOutputBytes = NULL,TInt* aInputWords = NULL);
+ IMPORT_C TInt FlushL(RWriteStream& aOutput,TInt aMaxOutputBytes,TInt& aOutputBytes);
+ IMPORT_C TInt FlushL(TUint8* aOutput,TInt aMaxOutputBytes,TInt& aOutputBytes);
+ IMPORT_C static TInt CompressedSizeL(MUnicodeSource& aInput,TInt aInputWords);
+
+ private:
+
+ // A structure to store a character and its treatment code
+ struct TAction
+ {
+ // Treatment codes: static and dynamic window numbers, plain ASCII or plain Unicode
+ enum
+ {
+ EPlainUnicode = -2, // character cannot be expressed as ASCII or using static or dynamic windows
+ EPlainASCII = -1, // character can be emitted as an ASCII code
+ EFirstDynamic = 0, // values 0..255 are for dynamic windows with offsets at these places in the offset table
+ ELastDynamic = 255,
+ EFirstStatic = 256, // values 256..263 are for static windows 0..7
+ ELastStatic = 263
+ };
+
+ inline TAction();
+ TAction(TUint16 aCode);
+
+ TUint16 iCode; // Unicode value of the character
+ TInt iTreatment; // treatment code: see above
+ };
+
+ void DoCompressL(RWriteStream* aOutputStream,TUint8* aOutputPointer,MUnicodeSource* aInput,
+ TInt aMaxCompressedBytes,TInt aMaxUnicodeWords,
+ TInt* aCompressedBytes,TInt* aUnicodeWords);
+ void FlushInputBufferL();
+ void FlushOutputBufferL();
+ void WriteRunL();
+ void WriteCharacter(const TAction& aAction);
+ void WriteSCharacter(const TAction& aAction);
+ void WriteUCharacter(TUint16 aCode);
+ void WriteByte(TUint aByte);
+ void WriteCharacterFromBuffer();
+ void SelectTreatment(TInt aTreatment);
+
+ enum
+ {
+ EMaxInputBufferSize = 4,
+ EMaxOutputBufferSize = EMaxInputBufferSize * 3 // no Unicode character can be encoded as more than three bytes
+ };
+ TAction iInputBuffer[EMaxInputBufferSize]; // circular buffer; queue of Unicode characters to be processed
+ TInt iInputBufferStart; // position of first Unicode character to be processed
+ TInt iInputBufferSize; // characters in the input buffer
+ TUint8 iOutputBuffer[EMaxOutputBufferSize]; // circular buffer; queue of compressed bytes to be output
+ TInt iOutputBufferStart; // position of first compressed byte to be output
+ TInt iOutputBufferSize; // characters in the output buffer
+ TInt iDynamicWindowIndex; // index of the current dynamic window
+ RWriteStream* iOutputStream; // if non-null, output is to this stream
+ TUint8* iOutputPointer; // if non-null, output is to memory
+ MUnicodeSource* iInput; // input object
+ };
+
+/**
+ * @publishedAll
+ * @released
+
+A class to hold functions to expand text using the Standard Compression Scheme for Unicode.
+
+A note on error handling and leaving.
+
+Although all the public functions except the constructor can leave, it is possible to guarantee success: that is,
+guarantee that a call will not leave, and that expansion will be completed. To do this, (i) supply a MUnicodeSink
+object with a non-leaving WriteUnicodeValueL function, such as a TMemoryUnicodeSink; (ii) read input from a RReadStream
+with a non-leaving ReadL function; (iii) supply a big enough buffer to write the ouput; you can find out how big by
+calling ExpandedSizeL, using methods (i) and (ii) to guarantee success.
+
+This guarantee of success is particularly useful when expanding from one memory buffer to another.
+*/
+class TUnicodeExpander: public TUnicodeCompressionState
+ {
+ public:
+ IMPORT_C TUnicodeExpander();
+ IMPORT_C void ExpandL(MUnicodeSink& aOutput,RReadStream& aInput,
+ TInt aMaxOutputWords = KMaxTInt,TInt aMaxInputBytes = KMaxTInt,
+ TInt* aOutputWords = NULL,TInt* aInputBytes = NULL);
+ IMPORT_C void ExpandL(MUnicodeSink& aOutput,const TUint8* aInput,
+ TInt aMaxOutputWords = KMaxTInt,TInt aMaxInputBytes = KMaxTInt,
+ TInt* aOutputWords = NULL,TInt* aInputBytes = NULL);
+ IMPORT_C TInt FlushL(MUnicodeSink& aOutput,TInt aMaxOutputWords,TInt& aOutputWords);
+ IMPORT_C static TInt ExpandedSizeL(RReadStream& aInput,TInt aInputBytes);
+ IMPORT_C static TInt ExpandedSizeL(const TUint8* aInput,TInt aInputBytes);
+
+ private:
+ void DoExpandL(MUnicodeSink* aOutput,RReadStream* aInputStream,const TUint8* aInputPointer,
+ TInt aMaxOutputWords,TInt aMaxInputBytes,
+ TInt* aOutputWords,TInt* aInputBytes);
+ void HandleByteL();
+ void FlushOutputBufferL();
+ TBool HandleSByteL(TUint8 aByte);
+ TBool HandleUByteL(TUint8 aByte);
+ TBool ReadByteL(TUint8& aByte);
+ TBool QuoteUnicodeL();
+ TBool DefineWindowL(TInt aIndex);
+ TBool DefineExpansionWindowL();
+ void WriteChar(TText aChar);
+ void WriteChar32(TUint aChar);
+
+ enum
+ {
+ EMaxInputBufferSize = 3, // no Unicode character can be encoded as more than 3 bytes
+ EMaxOutputBufferSize = 2 // no byte can be expanded into more than 2 Unicode characters
+ };
+ TUint8 iInputBuffer[EMaxInputBufferSize]; // buffer containing a group of compressed bytes representing
+ // a single operation; when an input source ends in the
+ // middle of an operation, this buffer enables the next
+ // expansion to start in the correct state
+ TInt iInputBufferStart; // next read position in the input buffer
+ TInt iInputBufferSize; // bytes in the input buffer
+ TUint16 iOutputBuffer[EMaxOutputBufferSize]; // circular buffer; queue of Unicode characters to be output
+ TInt iOutputBufferStart; // position of first Unicode character to be output
+ TInt iOutputBufferSize; // characters in the output buffer
+ MUnicodeSink* iOutput; // output object
+ RReadStream* iInputStream; // if non-null, input is from this stream
+ const TUint8* iInputPointer; // if non-null, input is from memory
+ };
+
+// inline functions start here
+
+inline TMemoryUnicodeSource::TMemoryUnicodeSource(const TUint16* aPtr):
+ iPtr(aPtr)
+ {
+ }
+
+inline TUint16 TMemoryUnicodeSource::ReadUnicodeValueL()
+ {
+ return *iPtr++;
+ }
+
+inline TMemoryStreamUnicodeSource::TMemoryStreamUnicodeSource(RReadStream& aStream):
+ iStream(aStream)
+ {
+ }
+
+inline TUint16 TMemoryStreamUnicodeSource::ReadUnicodeValueL()
+ {
+ TUint16 x;
+ iStream.ReadL((TUint8*)&x,sizeof(TUint16));
+ return x;
+ }
+
+inline TMemoryUnicodeSink::TMemoryUnicodeSink(TUint16* aPtr):
+ iPtr(aPtr)
+ {
+ }
+
+inline void TMemoryUnicodeSink::WriteUnicodeValueL(TUint16 aValue)
+ {
+ *iPtr++ = aValue;
+ }
+
+inline TMemoryStreamUnicodeSink::TMemoryStreamUnicodeSink(RWriteStream& aStream):
+ iStream(aStream)
+ {
+ }
+
+inline void TMemoryStreamUnicodeSink::WriteUnicodeValueL(TUint16 aValue)
+ {
+ iStream.WriteL((TUint8*)&aValue,sizeof(TUint16));
+ }
+
+inline TUnicodeCompressor::TAction::TAction():
+ iCode(0),
+ iTreatment(EPlainUnicode)
+ {
+ }
+
+#endif // _UNICODE
+
+#endif // __S32UCMP_H__