kernel/eka/euser/unicode/collateimp.h
changeset 0 a41df078684a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/euser/unicode/collateimp.h	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,163 @@
+// Copyright (c) 2000-2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of the License "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:
+//
+
+// Some internals of the Unicode collation system.
+#ifndef __COLLATEIMP_H__
+#define __COLLATEIMP_H__
+
+#include <e32std.h>
+#include "collate.h"
+#include "CompareImp.h"
+
+//Forward declarations
+struct TCollationKeyTable;
+
+//External declarations
+const TCollationKeyTable* StandardCollationMethod();
+
+/**
+@internalComponent
+*/
+struct TCollationKey
+	{
+	enum { KHighValue = 0x00FFFFFF, KFlagIsStarter = 0x80000000 };
+	TUint32 Level(TInt aLevel) const
+		{
+		static const TUint32 mask[3] = { 0xFFFF0000, 0xFF00, 0xFC };
+		return aLevel == 3 ? iHigh & KHighValue : iLow & mask[aLevel];
+		}
+	TBool IsStarter() const
+        { 
+        return (TBool)(iHigh & (TUint32)KFlagIsStarter);
+        }
+    
+    enum {KLevel0KeySize=2, KLevel1KeySize=1,KLevel2KeySize=1,KLevel3KeySize=3 };
+        
+	static TInt MaxSizePerKey(TInt aLevel)
+		{
+		if (aLevel==0)
+			return KLevel0KeySize;
+		if (aLevel==1 || aLevel==2)
+			return KLevel1KeySize;
+		return KLevel3KeySize;			
+		}
+
+	void AppendToDescriptor(TPtr8 aLevelBuffer,TInt aLevel) const
+		{
+		TBuf8<4> buffer;
+		switch (aLevel)
+			{
+			//for each level need to check for zero key
+			//i.e. only append non zero key
+			case 0:
+				{
+				if (((iLow>>16)&0xFFFF)!=0)
+					{
+					buffer.SetLength(KLevel0KeySize);
+					buffer[0]=(TUint8)((iLow>>24)&0xFF);
+					buffer[1]=(TUint8)((iLow>>16)&0xFF);
+					}
+				break;
+				}
+			case 1:
+				{
+				if (((iLow>>8)&0xFF)!=0)
+					{
+					buffer.SetLength(KLevel1KeySize);
+					buffer[0]=(TUint8)((iLow>>8)&0xFF);
+					}
+				break;
+				}
+			case 2:
+				{
+				if ((iLow&0xFC)!=0)
+					{
+					buffer.SetLength(KLevel2KeySize);
+					buffer[0]=(TUint8)(iLow&0xFC);
+					}
+				break;
+				}
+			case 3:
+				{
+				if ((iHigh&0xFFFFFF)!=0)
+					{
+					buffer.SetLength(KLevel3KeySize);
+					buffer[0]=(TUint8)((iHigh>>16)&0xFF);
+					buffer[1]=(TUint8)((iHigh>>8)&0xFF);
+					buffer[2]=(TUint8)(iHigh&0xFF);
+					}
+				break;
+				}
+			}
+			aLevelBuffer.Append(buffer);
+		}
+ 
+	TUint32 iLow;				// primary, secondary and tertiary keys
+	TUint32 iHigh;				// quaternary key; usually the Unicode value
+	};
+
+/**
+@internalComponent
+*/
+struct TKeyInfo
+	{
+	enum { EMaxKeys = 8 };
+
+	TCollationKey iKey[EMaxKeys];	// the keys
+	TInt iKeys;						// the number of keys returned
+	TInt iCharactersConsumed;		// number of characters consumed from the input to generate the keys
+	};
+
+/**
+Steps through a decomposed unicode string (using iDecompStrIt iterator), 
+outputting raw collation keys.
+Every Increment() call will move to the next collation key (from iKey array), if available.
+Every GetCurrentKey() call will retrieve current collation key, if available.
+@internalComponent
+*/
+class TCollationValueIterator
+	{
+public:
+	inline TCollationValueIterator(const TCollationMethod& aMethod);
+	void SetSourceIt(TUTF32Iterator& aSourceIt);
+	TBool GetCurrentKey(TCollationKey& aKey);
+    TBool GetCurrentKey(TInt aLevel, TUint32& aKey);
+    TUint32 GetNextNonZeroKey(TInt aLevel);
+    TBool MatchChar(TChar aMatch);
+    TBool AtCombiningCharacter();
+    TInt SkipCombiningCharacters();
+	TBool Increment();
+	inline TBool IgnoringNone() const;
+	inline const TCollationMethod& CollationMethod() const;
+	const TText16* CurrentPositionIfAtCharacter();
+
+private:
+	TBool ProduceCollationKeys();
+	void GetNextRawKeySequence();
+	void GetKeyFromTable(const TCollationKeyTable* aTable);
+
+private:
+	TCanonicalDecompositionIteratorCached iDecompStrIt;//Used to iterate through the canonically decomposed input string
+	// Current position in the underlying iterator (if well defined)
+	// of the start of the keys stored in iKey.
+	const TText16* iCurrentPosition;
+	const TCollationMethod& iMethod;//Current (locale dependend) collation method
+	TKeyInfo iKey;//Each ProduceCollationKeys() call fills it with the longest possible collation keys sequence
+    TInt iCurrentKeyPos;//Current position in iKey array. Incremented/set to 0 after each Increment() call
+	};
+
+#include "CollateImp.inl"
+
+#endif //__COLLATEIMP_H__