os/persistentdata/loggingservices/eventlogger/LogServ/inc/LogServCacheStrings.h
changeset 0 bde4ae8d615e
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/persistentdata/loggingservices/eventlogger/LogServ/inc/LogServCacheStrings.h	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,118 @@
     1.4 +// Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.5 +// All rights reserved.
     1.6 +// This component and the accompanying materials are made available
     1.7 +// under the terms of "Eclipse Public License v1.0"
     1.8 +// which accompanies this distribution, and is available
     1.9 +// at the URL "http://www.eclipse.org/legal/epl-v10.html".
    1.10 +//
    1.11 +// Initial Contributors:
    1.12 +// Nokia Corporation - initial contribution.
    1.13 +//
    1.14 +// Contributors:
    1.15 +//
    1.16 +// Description:
    1.17 +//
    1.18 +
    1.19 +#ifndef __LOGSERVCACHESTRINGS_H__
    1.20 +#define __LOGSERVCACHESTRINGS_H__
    1.21 +
    1.22 +#include <logwrap.h>
    1.23 +#include <logwraplimits.h>
    1.24 +
    1.25 +// Classes referenced
    1.26 +class MLogServDatabaseTransactionInterface;
    1.27 +
    1.28 +/**
    1.29 +Caches the most often used strings, such as "Incoming", "Outgoing", "Missed", etc.
    1.30 +Every string in the cache is identified by an ID. The cached strings come from 
    1.31 +event's "status" and "direction" fields. If an event is about to be added to the events database
    1.32 +table, instead of storing in the table often repeated "status" and "direction" string fields values,
    1.33 +the CLogServCacheStrings is searched for the ID of the string. If such string is already in the cache
    1.34 +its ID is returned, if no such string is found in the cache, then the string will be added to the cache 
    1.35 +and the ID of the added string is returned. The returned ID will be stored as part of the event 
    1.36 +properties in the events table. 
    1.37 +
    1.38 +Wherever the strings cache is changed, if the database is already in transaction, the cache changes will
    1.39 +be committed/rolled back when the transaction is committed/rolled back.
    1.40 +
    1.41 +Note: the often used LogEng strings are kept in a database table with name "String".
    1.42 +
    1.43 +@see CLogAddEvent
    1.44 +@see CLogEvent
    1.45 +@see MLogServDatabaseTransactionInterface
    1.46 +@internalComponent
    1.47 +*/
    1.48 +class CLogServCacheStrings : public CBase
    1.49 +	{
    1.50 +public:
    1.51 +	static CLogServCacheStrings* NewL(MLogServDatabaseTransactionInterface& aDatabase);
    1.52 +	~CLogServCacheStrings();
    1.53 +
    1.54 +	const TPtrC  FindString(TLogStringId aId) const;
    1.55 +	TLogStringId FindId(const TDesC& aString);
    1.56 +	TLogStringId GetIdL(const TDesC& aString);
    1.57 +	void Commit();
    1.58 +	void Rollback();
    1.59 +
    1.60 +private:
    1.61 +   	struct TLogServCacheStringEntry
    1.62 +		{
    1.63 +		public:
    1.64 +			static void CleanupEntry(TAny* aEntry);
    1.65 +			static inline TLogServCacheStringEntry* NewEntryL(TLogStringId aId, const TDesC& aString, TBool aDirty = EFalse)
    1.66 +				{
    1.67 +				TUint8* entry = (TUint8*)User::AllocL(sizeof(TLogServCacheStringEntry) + aString.Size());
    1.68 +				return new (entry) TLogServCacheStringEntry(aId, aString, aDirty);
    1.69 +				}
    1.70 +			static inline TLogServCacheStringEntry* NewEntryLC(TLogStringId aId, const TDesC& aString, TBool aDirty = EFalse)
    1.71 +				{
    1.72 +				TLogServCacheStringEntry* entry = TLogServCacheStringEntry::NewEntryL(aId, aString, aDirty);
    1.73 +				CleanupStack::PushL(TCleanupItem(&TLogServCacheStringEntry::CleanupEntry, entry));
    1.74 +				return entry;
    1.75 +				}
    1.76 +			static inline void DeleteEntry(TLogServCacheStringEntry* aEntry)
    1.77 +				{
    1.78 +				User::Free(aEntry);
    1.79 +				}
    1.80 +			inline const TPtrC String() const
    1.81 +				{
    1.82 +				return TPtrC(iString, iStringLength);
    1.83 +				}
    1.84 +		private:
    1.85 +			inline TLogServCacheStringEntry(TLogStringId aId, const TDesC& aString, TBool aDirty) :
    1.86 +				iId(aId),
    1.87 +				iDirty(aDirty),
    1.88 +				iStringLength(aString.Length())
    1.89 +				{
    1.90 +				(void)Mem::Copy(iString, aString.Ptr(), aString.Size());
    1.91 +				}
    1.92 +			TLogServCacheStringEntry();				
    1.93 +			TLogServCacheStringEntry(const TLogServCacheStringEntry&);
    1.94 +			TLogServCacheStringEntry& operator=(const TLogServCacheStringEntry&);
    1.95 +		public:		
    1.96 +			TLogStringId 	iId;
    1.97 +			TBool 			iDirty;//if set, this entry has been added to the cache during transaction
    1.98 +		private:			
    1.99 +			TInt 			iStringLength;
   1.100 +			TText 			iString[1];
   1.101 +		};
   1.102 +
   1.103 +	CLogServCacheStrings(MLogServDatabaseTransactionInterface& aDatabase);
   1.104 +	void ConstructL();
   1.105 +	void ReadStringsFromDatabaseL();
   1.106 +	TLogStringId DoAddStringL(const TDesC& aString);
   1.107 +	void DestroyCache();
   1.108 +	void InitializeColNumsL(RDbRowSet& aRowSet);
   1.109 +	static TInt Compare1(const TDesC* aString, TLogServCacheStringEntry* const& aRight);
   1.110 +	static TInt Compare2(TLogServCacheStringEntry* const& aLeft, TLogServCacheStringEntry* const& aRight);
   1.111 +
   1.112 +private:
   1.113 +	MLogServDatabaseTransactionInterface& iDatabase;
   1.114 +	RArray<TLogServCacheStringEntry*> iStrings;//List of cached strings
   1.115 +	TBool iDirty;//iDirty flag is set when strings are added to the cache during transaction
   1.116 +	TDbColNo iIdColNo;
   1.117 +	TDbColNo iStringColNo;
   1.118 +	
   1.119 +	};
   1.120 +
   1.121 +#endif