sl@0: // Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: //
sl@0: 
sl@0: #ifndef __LOGSERVCACHESTRINGS_H__
sl@0: #define __LOGSERVCACHESTRINGS_H__
sl@0: 
sl@0: #include <logwrap.h>
sl@0: #include <logwraplimits.h>
sl@0: 
sl@0: // Classes referenced
sl@0: class MLogServDatabaseTransactionInterface;
sl@0: 
sl@0: /**
sl@0: Caches the most often used strings, such as "Incoming", "Outgoing", "Missed", etc.
sl@0: Every string in the cache is identified by an ID. The cached strings come from 
sl@0: event's "status" and "direction" fields. If an event is about to be added to the events database
sl@0: table, instead of storing in the table often repeated "status" and "direction" string fields values,
sl@0: the CLogServCacheStrings is searched for the ID of the string. If such string is already in the cache
sl@0: its ID is returned, if no such string is found in the cache, then the string will be added to the cache 
sl@0: and the ID of the added string is returned. The returned ID will be stored as part of the event 
sl@0: properties in the events table. 
sl@0: 
sl@0: Wherever the strings cache is changed, if the database is already in transaction, the cache changes will
sl@0: be committed/rolled back when the transaction is committed/rolled back.
sl@0: 
sl@0: Note: the often used LogEng strings are kept in a database table with name "String".
sl@0: 
sl@0: @see CLogAddEvent
sl@0: @see CLogEvent
sl@0: @see MLogServDatabaseTransactionInterface
sl@0: @internalComponent
sl@0: */
sl@0: class CLogServCacheStrings : public CBase
sl@0: 	{
sl@0: public:
sl@0: 	static CLogServCacheStrings* NewL(MLogServDatabaseTransactionInterface& aDatabase);
sl@0: 	~CLogServCacheStrings();
sl@0: 
sl@0: 	const TPtrC  FindString(TLogStringId aId) const;
sl@0: 	TLogStringId FindId(const TDesC& aString);
sl@0: 	TLogStringId GetIdL(const TDesC& aString);
sl@0: 	void Commit();
sl@0: 	void Rollback();
sl@0: 
sl@0: private:
sl@0:    	struct TLogServCacheStringEntry
sl@0: 		{
sl@0: 		public:
sl@0: 			static void CleanupEntry(TAny* aEntry);
sl@0: 			static inline TLogServCacheStringEntry* NewEntryL(TLogStringId aId, const TDesC& aString, TBool aDirty = EFalse)
sl@0: 				{
sl@0: 				TUint8* entry = (TUint8*)User::AllocL(sizeof(TLogServCacheStringEntry) + aString.Size());
sl@0: 				return new (entry) TLogServCacheStringEntry(aId, aString, aDirty);
sl@0: 				}
sl@0: 			static inline TLogServCacheStringEntry* NewEntryLC(TLogStringId aId, const TDesC& aString, TBool aDirty = EFalse)
sl@0: 				{
sl@0: 				TLogServCacheStringEntry* entry = TLogServCacheStringEntry::NewEntryL(aId, aString, aDirty);
sl@0: 				CleanupStack::PushL(TCleanupItem(&TLogServCacheStringEntry::CleanupEntry, entry));
sl@0: 				return entry;
sl@0: 				}
sl@0: 			static inline void DeleteEntry(TLogServCacheStringEntry* aEntry)
sl@0: 				{
sl@0: 				User::Free(aEntry);
sl@0: 				}
sl@0: 			inline const TPtrC String() const
sl@0: 				{
sl@0: 				return TPtrC(iString, iStringLength);
sl@0: 				}
sl@0: 		private:
sl@0: 			inline TLogServCacheStringEntry(TLogStringId aId, const TDesC& aString, TBool aDirty) :
sl@0: 				iId(aId),
sl@0: 				iDirty(aDirty),
sl@0: 				iStringLength(aString.Length())
sl@0: 				{
sl@0: 				(void)Mem::Copy(iString, aString.Ptr(), aString.Size());
sl@0: 				}
sl@0: 			TLogServCacheStringEntry();				
sl@0: 			TLogServCacheStringEntry(const TLogServCacheStringEntry&);
sl@0: 			TLogServCacheStringEntry& operator=(const TLogServCacheStringEntry&);
sl@0: 		public:		
sl@0: 			TLogStringId 	iId;
sl@0: 			TBool 			iDirty;//if set, this entry has been added to the cache during transaction
sl@0: 		private:			
sl@0: 			TInt 			iStringLength;
sl@0: 			TText 			iString[1];
sl@0: 		};
sl@0: 
sl@0: 	CLogServCacheStrings(MLogServDatabaseTransactionInterface& aDatabase);
sl@0: 	void ConstructL();
sl@0: 	void ReadStringsFromDatabaseL();
sl@0: 	TLogStringId DoAddStringL(const TDesC& aString);
sl@0: 	void DestroyCache();
sl@0: 	void InitializeColNumsL(RDbRowSet& aRowSet);
sl@0: 	static TInt Compare1(const TDesC* aString, TLogServCacheStringEntry* const& aRight);
sl@0: 	static TInt Compare2(TLogServCacheStringEntry* const& aLeft, TLogServCacheStringEntry* const& aRight);
sl@0: 
sl@0: private:
sl@0: 	MLogServDatabaseTransactionInterface& iDatabase;
sl@0: 	RArray<TLogServCacheStringEntry*> iStrings;//List of cached strings
sl@0: 	TBool iDirty;//iDirty flag is set when strings are added to the cache during transaction
sl@0: 	TDbColNo iIdColNo;
sl@0: 	TDbColNo iStringColNo;
sl@0: 	
sl@0: 	};
sl@0: 
sl@0: #endif