// Copyright (c) 2001-2009 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:

 //

 #include <e32base.h>

 #include "StringPoolImplementation.h"

 const TInt KMapGranularity=20;

 CStringPoolNode::~CStringPoolNode()

 	{

 	delete iDes;

 	}

 CStringPoolImplementation::CStringPoolImplementation() : iStringMapList(KMapGranularity, _FOFF(TStringIdMap, iSourceTableVal)), iStringMapListReverse(KMapGranularity, _FOFF(TStringIdMap, iTargetTableVal))

 	{

 	}

 CStringPoolImplementation::~CStringPoolImplementation()

 	{

 	// Look for non-expirable strings

 	TInt i;

 	for (i = 0; i < KHashModulo; i++ )

 		{

 		DeleteUndeletableStrings(iCIHashTable, i);

 		DeleteUndeletableStrings(iCSHashTable, i);		

 		}

 #ifdef _DEBUG

 	__LOG(_L8(":Closing String Pool.\n"))

 		TBool leaksFound = EFalse;

 	// Check that the string pool is empty, or more accurately that

 	// everything in it is a pre-loaded string

 	for (i = 0; i < KHashModulo; i++ )

 		{

 		if (iCIHashTable[i])

 			{

 			for (TInt j = 0; j < iCIHashTable[i]->Count(); j++)

 				{

 				if (!StringUtils::IsTableEntry(iCIHashTable[i]->At(j).iVal))

 					{

 					if (!leaksFound)

 						{

 						__LOG(_L8("The following strings were leaked through not being Closed:\n"))

 						leaksFound = ETrue;

 						}

 					// Get the problem string

 					CStringPoolNode* theProblem = 

 						reinterpret_cast<CStringPoolNode*>(

 							iCIHashTable[i]->At(j).iVal & KTokenToNode);

 					if(theProblem->iDes)

 					    __LOG(theProblem->iDes->Des());

 					}

 				}

 			}

 		if (iCSHashTable[i])

 			{

 			for (TInt j = 0; j < iCSHashTable[i]->Count(); j++)

 				{

 				if (!StringUtils::IsTableEntry(iCSHashTable[i]->At(j).iVal))

 					{

 					if (!leaksFound)

 						{

 						__LOG(_L8("The following strings were leaked through not being Closed:\n"))

 						leaksFound = ETrue;

 						}

 					// Get the problem string

 					CStringPoolNode* theProblem = 

 						reinterpret_cast<CStringPoolNode*>(

 							iCSHashTable[i]->At(j).iVal & KTokenToNode);

 					if(theProblem->iDes)

 					    __LOG(theProblem->iDes->Des());

 					}

 				}

 			}

 		if (leaksFound)

 			__DEBUGGER();

 		}

 	if (!leaksFound)

 		__LOG(_L8("No leakages were detected\n"));

 #endif //_DEBUG

 	for (TInt ii = 0; ii < KHashModulo; ii++)

 		{

 		delete iCIHashTable[ii];

 		delete iCSHashTable[ii];

 		}

 	iTablePtrs.Close();

 	iStringMapList.Close();

 	iStringMapListReverse.Close();

 	iRollbackMapList.Close();	

 	iRollbackHashListCS.Close();

 	iRollbackHashListCI.Close();

 	// Notify the external users of the StringPool that the object is getting closed

 	TInt cBCounter = iCallBacks.Count();

 	if(cBCounter>0)

 		{

 		while (--cBCounter>=0)

 			{

 			iCallBacks[cBCounter]->StringPoolClosing();

 			}

 		}

 	iCallBacks.Close();

 	}

 // Check for any undeletable string and delete them now

 void CStringPoolImplementation::DeleteUndeletableStrings(CArrayFixSeg<RStringTokenEither>* aArray[KHashModulo], TInt i)

 	{

 	if (aArray[i])

 		{

 		for (TInt j = 0; j < aArray[i]->Count(); ++j)

 			{

 			if (!StringUtils::IsTableEntry(aArray[i]->At(j).iVal))

 				{

 				CStringPoolNode* node= reinterpret_cast<CStringPoolNode*>(aArray[i]->At(j).iVal & KTokenToNode);

 				if (KMarkedForNoDeleted==node->iRefcount)

 					{

 					delete node;										

 					aArray[i]->Delete(j);

 					j--;

 					}

 				}

 			}

 		}	

 	}

 CStringPoolImplementation* CStringPoolImplementation::NewL()

 	{

 	CStringPoolImplementation* table = new (ELeave) CStringPoolImplementation();	

 	return table;

 	}

 void CStringPoolImplementation::CleanupHashCS(TAny* aImplementation)

 	{

 	CStringPoolImplementation* imp=reinterpret_cast<CStringPoolImplementation*>(aImplementation);

 	CleanUpHash(&imp->iRollbackHashListCS, imp->iCSHashTable);

 	}

 void CStringPoolImplementation::CleanupHashCI(TAny* aImplementation)

 	{

 	CStringPoolImplementation* imp=reinterpret_cast<CStringPoolImplementation*>(aImplementation);

 	CleanUpHash(&imp->iRollbackHashListCI, imp->iCIHashTable);

 	}

 void CStringPoolImplementation::CleanUpHash(RPointerArray <RStringTokenEither>* aHashCleanup, CArrayFixSeg<RStringTokenEither>* aHash[KHashModulo])

 	{

 	if (aHashCleanup->Count()>0)

 		{

 		RStringTokenEither* token=(*aHashCleanup)[0];	// Get first entry

 		for (TInt i = 0; i < KHashModulo; i++ )

 			{

 			if (aHash[i])

 				{

 				for (TInt j = 0; j < aHash[i]->Count(); j++)

 					{

 					if (!StringUtils::IsTableEntry(aHash[i]->At(j).iVal))

 						{						

 						if (aHash[i]->At(j).iVal==token->iVal)

 							{		

 							CStringPoolNode* node= reinterpret_cast<CStringPoolNode*>(aHash[i]->At(j).iVal & KTokenToNode);

 							delete node;

 							aHash[i]->Delete(j);

 							aHashCleanup->Remove(0);

 							break;

 							}

 						}

 					}

 				}

 			}

 		}

 	}

 void CStringPoolImplementation::CleanupIdMap(TAny* aImplementation)

 	{

 	CStringPoolImplementation* imp=reinterpret_cast<CStringPoolImplementation*>(aImplementation);

 	if (imp->iRollbackMapList.Count()>0)

 		{

 		TStringIdMap* map=imp->iRollbackMapList[0];			

 		TInt index=imp->iStringMapList.FindInUnsignedKeyOrder(*map);

 		imp->iRollbackMapList.Remove(0);

 		if (index!=KErrNotFound)

 			{

 			imp->iStringMapList.Remove(index);			

 			}		

 		index=imp->iStringMapListReverse.FindInUnsignedKeyOrder(*map);

 		if (index!=KErrNotFound)

 			{

 			for (TInt count=index;count<imp->iStringMapListReverse.Count();++count)

 				{

 				if (imp->iStringMapListReverse[count].iTargetTableVal==map->iTargetTableVal && imp->iStringMapListReverse[count].iSourceTableVal==map->iSourceTableVal)

 					{				

 					imp->iStringMapListReverse.Remove(index);

 					}

 				}

 			}

 		}

 	}

 void CStringPoolImplementation::AddTableL(const TStringTable& aTable)

 	{

 	for (TInt count=0;count<iTablePtrs.Count();++count)	// check for adding the same table twice

 		{

 		if (iTablePtrs[count]==&aTable)

 			{

 			return;

 			}

 		}

 	User::LeaveIfError(iTablePtrs.Append(&aTable));	// Add the pointer to this table so we can keep track of the Table IDs. The table ID is the index in this array

 	//Is the table Case Sensitive or not?

 	TBool (*genericValFromIndex)(TInt, TUint16);

 	if (aTable.iCaseSensitive==1)

 		genericValFromIndex = StringUtils::ValFromIndex;

 	else

 		genericValFromIndex = StringUtils::ValFromIndexF;

 	CArrayFixSeg<RStringTokenEither>** hashTableToUse =

 	aTable.iCaseSensitive ? iCSHashTable :iCIHashTable ;	

 	TInt cleanupCounter=0;

 	for (TUint i = 0; i < aTable.iCount; ++i)

 		{

 		const TStLitC8<1>* string=reinterpret_cast<const TStLitC8<1>* >(aTable.iTable[i]);		

 		// Try to find the string in memory, maybe as a dynamic string or as a member of an another table  

 		RStringTokenEither token=FindDes(*string, !aTable.iCaseSensitive);

 		if (!token.IsNull())

 			{

 			TStringIdMap map;			

 			map.iSourceTableVal=StringUtils::ValFromIndex(i, (TInt16)(iTablePtrs.Count()-1),aTable.iCaseSensitive);

 			map.iTargetTableVal=token.iVal;

 			// Put on cleanup stack

 			User::LeaveIfError(iRollbackMapList.Append(&map));

 			TCleanupItem cleanup(CleanupIdMap, this);

 			CleanupStack::PushL(cleanup);

 			++cleanupCounter;

 			User::LeaveIfError(iStringMapList.InsertInUnsignedKeyOrder(map));

 			// Check if this is a link to a dynamic string

 			if (!StringUtils::IsTableEntry(token.iVal))

 				{

 				CStringPoolNode* node = StringUtils::NodePtr(token.iVal);

 				node->iRefcount=KMarkedForNoDeleted; // Make sure this string never gets deleted

 				}

 			// Now store the reverse array						

 			User::LeaveIfError(iStringMapListReverse.InsertInUnsignedKeyOrderAllowRepeats(map));

 			}

 		else

 			{

 			TUint8 hash = static_cast<TUint8>(Hash(*string));

 			CArrayFixSeg<RStringTokenEither>* collisionList = hashTableToUse[hash];

 			if ( !collisionList )

 				//HashTableToUse now is used as list of all entry with the same hash

 				collisionList = hashTableToUse[hash] = 

 				new (ELeave) CArrayFixSeg<RStringTokenEither>( 2 );

 			RStringTokenEither s;

 			s.iVal = genericValFromIndex(i, (TInt16)(iTablePtrs.Count()-1));

 			__LOG2(_L8("Table entry being added with hash %d, val %d"), hash, s.iVal);

 			__LOG(*reinterpret_cast<const TStLitC8<1>* >(aTable.iTable[i]));

 			// Put on cleanup stack

 			if (aTable.iCaseSensitive==1)

 				{

 				User::LeaveIfError(iRollbackHashListCS.Append(&s));

 				TCleanupItem cleanup(CleanupHashCS, this);

 				CleanupStack::PushL(cleanup);

 				}

 			else

 				{

 				User::LeaveIfError(iRollbackHashListCI.Append(&s));

 				TCleanupItem cleanup(CleanupHashCI, this);

 				CleanupStack::PushL(cleanup);

 				}

 			++cleanupCounter;

 			collisionList->AppendL(s);

 			}

 		}	

 	CleanupStack::Pop(cleanupCounter);

 	iRollbackMapList.Reset();

 	iRollbackHashListCS.Reset();

 	iRollbackHashListCI.Reset();

 	}

 // Find FirstVal given duplicate val

 TInt32 CStringPoolImplementation::FindFirstValFromDuplicate(TInt32 aDuplicateVal) const 

 	{

 	TStringIdMap map;

 	map.iSourceTableVal=aDuplicateVal;	

 	TInt index=iStringMapList.FindInUnsignedKeyOrder(map);

 	if (index!=KErrNotFound)		

 		return iStringMapList[index].iTargetTableVal;

 	else

 		return KErrNotFound;

 	}

 // Find table index Val given first val & table UID

 TInt CStringPoolImplementation::FindTableIndexFromFirstVal(TInt32 aFirstVal, TInt aTableUid) const

 	{

 	TStringIdMap map;

 	map.iTargetTableVal=aFirstVal;		

 	TInt index=iStringMapListReverse.FindInUnsignedKeyOrder(map);

 	if (KErrNotFound==index)

 		return KErrNotFound;

 	for (TInt count=index;count<iStringMapListReverse.Count();++count)

 		{

 		if (iStringMapListReverse[count].iTargetTableVal==aFirstVal && StringUtils::TableUid(iStringMapListReverse[count].iSourceTableVal)==aTableUid)

 			{

 			return StringUtils::TableIndex(iStringMapListReverse[count].iSourceTableVal);

 			}

 		}	

 		return KErrNotFound;

 	}

 // Find the UId for a given table

 TInt16 CStringPoolImplementation::TableUid(const TStringTable& aTable) const

 	{

 	for (TInt count=0; count<iTablePtrs.Count(); ++count)

 		{

 		if (iTablePtrs[count]==&aTable)

 			return (TInt16)count;

 		}

 	return KErrNotFound;

 	}

 // Find a reference to the table that first added the  string represented by aVal to the pool 

 const TStringTable& CStringPoolImplementation::TableRef(TInt32 aVal) const

 	{

 	__ASSERT_DEBUG(aVal!=0, StringPoolPanic::Panic(StringPoolPanic::EIllegalUseOfNullString));

 	TInt16 tableUid=(TInt16)(aVal>>20);

 	const TStringTable* theTableRef=(iTablePtrs[tableUid]);

 	return  *theTableRef;

 	}

 // Find the descriptor for a given table and index

 const TDesC8& CStringPoolImplementation::TableLookup(TInt aIndex, TInt aTableUid) const

 	{	

 	return *reinterpret_cast<const TStLitC8<1>*>(iTablePtrs[aTableUid]->iTable[aIndex]);

 	}

 // Lookup with allocating

 //

 RStringTokenEither 

 CStringPoolImplementation::OpenL( const TDesC8& aAttributeName,

 								  TBool aCaseInsensitive)

 	{

 	// lookup the attribute

 	RStringTokenEither s(FindDes( aAttributeName , aCaseInsensitive));

 	if (!s.IsNull())

 		{

 		if (!StringUtils::IsTableEntry(s.iVal))

 			{

 			CStringPoolNode* node = StringUtils::NodePtr(s.iVal);

 			if (KMarkedForNoDeleted!=node->iRefcount)

 				node->iRefcount++;

 			__LOG1(_L8("String copied (during open). Count is now %d"), node->iRefcount);

 			__LOG(*node->iDes);

 			}

 		return s;

 		}

 	// create a new node at the end of the appropriate array

 	CStringPoolNode* newnode = new (ELeave) CStringPoolNode();

 	CleanupStack::PushL( newnode );

 	newnode->iDes = aAttributeName.AllocL();

 	newnode->iRefcount = 1;

 	TInt hash = Hash( aAttributeName );

 	CArrayFixSeg<RStringTokenEither>** hashTableToUse = 

 		aCaseInsensitive ? iCIHashTable : iCSHashTable;

 	__LOG2(_L8("Newly added with hash value %d, node val 0x%x\n"), hash, newnode)

 	__LOG(aAttributeName);

 	newnode->iHash = static_cast<TUint8>(hash);

 	CArrayFixSeg<RStringTokenEither>* collisionList = hashTableToUse[hash];

 	if ( !collisionList )

 		collisionList = hashTableToUse[hash] = new (ELeave) CArrayFixSeg<RStringTokenEither>( 2 );

 	s.iVal = reinterpret_cast<TUint32>(newnode);

 	if (aCaseInsensitive)

 		s.iVal += 2;

 	collisionList->AppendL(s);

 	CleanupStack::Pop(); // newnode

 	return s;

 	}

 void CStringPoolImplementation::Close(RStringTokenEither aString)

 	{

 	if (StringUtils::IsTableEntry(aString.iVal))

 		return;

 	CStringPoolNode* node = StringUtils::NodePtr(aString.iVal);

 	if (KMarkedForNoDeleted == node->iRefcount)	// -1 means a non-expirable string

 		return;

 	if (--node->iRefcount == 0)

 		{

 		//this is  the last reference of this string

 		CArrayFixSeg<RStringTokenEither>** hashTableToUse = 

 		aString.iVal & 2 ? iCIHashTable : iCSHashTable;

 		// Delete the node and delete the entry in the relevant collision list 

 		CArrayFixSeg<RStringTokenEither>* collisionList = hashTableToUse[node->iHash];

 		TInt count = collisionList->Count();		

 		for (TInt i = 0; i < count; i++)

 			{

 			if (collisionList->At(i) == aString)

 				{

 				// Log the fact that a string reference is about to die...

 				__LOG1(_L8("Removing string with hash value %d\n"), node->iHash)

 				__LOG(node->iDes->Des());

 				collisionList->Delete(i);

 				break;

 				}

 			}

 		delete node;

 		}

 	else

 		{

 		__LOG1(_L8("String closed. Count is now %d"), 

 			   node->iRefcount);

 		__LOG(node->iDes->Des());

 		}

 	}

 void CStringPoolImplementation::IncrementCount(RStringTokenEither aString)

 	{

 	if (StringUtils::IsTableEntry(aString.iVal))

 		return;

 	CStringPoolNode* node = StringUtils::NodePtr(aString.iVal);

 	if (KMarkedForNoDeleted!=node->iRefcount)

 		node->iRefcount++;

 	__LOG1(_L8("String copied. Count is now %d"), node->iRefcount);

 	__LOG(*node->iDes);

 	}

 // Very simple case-sensitive comparison. We can assume that the

 // strings are the same length, and we only care if the strings are

 // the same. (Unlike normal comparison functions that also tell you

 // which one is 'smaller')

 TBool CStringPoolImplementation::CompareCS(const TDesC8& s1, const TDesC8& s2)

 	{

 	const TUint8* ptr1 = s1.Ptr();

 	const TUint8* ptr2 = s2.Ptr();

 	const TUint8* stop = &ptr1[s1.Length()];

 	for (; ptr1 < stop; ptr1++,ptr2++)

 		{

 		if (*ptr1 != *ptr2)

 			return EFalse;

 		}

 	return ETrue;

 	}

 // Note that the hash function must generate the same hash values for

 // strings that differ by case. If changing the algorithm here make

 // sure this is still true.

 TBool CStringPoolImplementation::CompareCI(const TDesC8& s1, const TDesC8& s2)

 	{

 	const TUint8* ptr1 = s1.Ptr();

 	const TUint8* ptr2 = s2.Ptr();

 	const TUint8* stop = &ptr1[s1.Length()];

 	for (; ptr1 < stop; ptr1++,ptr2++)

 		{

 		if (*ptr1 != *ptr2)

 			{

 			// They're not exactly the same; see if they differ only

 			// by case. If one character is a letter, we can do a

 			// comparison ignoring bit 5 in both cases. If that

 			// matches, they are the same.

 			if (!((*ptr1 & KCaseInsensitive) == (*ptr2 & KCaseInsensitive) &&

 				  (*ptr1 >= 'A' && *ptr1 <= 'Z' || 

 				   *ptr1 >= 'a' && *ptr1 <= 'z')))

 				return EFalse;

 			}

 		}

 	return ETrue;

 	}

 // Find the given descriptor in the hash table

 //

 RStringTokenEither 

 CStringPoolImplementation::FindDes( const TDesC8& aAttributeName, TBool aCaseInsensitive) 

 	{

 	CArrayFixSeg<RStringTokenEither>** hashTableToUse = 

 		aCaseInsensitive ? iCIHashTable : iCSHashTable;

 	CArrayFixSeg<RStringTokenEither>* collisionList =hashTableToUse[Hash(aAttributeName)];

 	RStringPool pool;

 	TBool (*compareFunction)(const TDesC8&, const TDesC8&);

 	if (aCaseInsensitive)

 		compareFunction = CompareCI;

 	else

 		compareFunction = CompareCS;

 	pool.iImplementation = this;

 	if ( collisionList )

 		{

 		TInt length=aAttributeName.Length();

 		TInt count = collisionList->Count();

 		for ( TInt i = 0; i < count; i++ )

 			{

 			RStringTokenEither token = collisionList->At(i);

 			RStringEither s(this, token);

 			const TDesC8& string = s.DesC();

 			if ( string.Length()==length && 

 				 (*compareFunction)(aAttributeName, string))

 				return token;

 			}

 		}

 	return RStringTokenEither();

 	}

 // Generate a hash value

 //

 TUint CStringPoolImplementation::Hash( const TDesC8& aDes ) const

 	{

 	// We ignore bit 5, which is a crude way of making the hash case

 	// insensitive. This means that things that might differ only by

 	// case end up in the same bucket, and we can then worry about

 	// whether they're really the same later.

 	TInt len=aDes.Length();

 	TUint hash = 0;

 	const TUint8* ptr=aDes.Ptr();

 	for ( TInt i = 0; i < len; i++ )

 		hash = 131*hash + (*ptr++ & KCaseInsensitive);

 	return hash % KHashModulo;

 	}

 TInt StringUtils::ValFromIndex(TInt aIndex, TUint16 aTableId)

 	{

 	return (aTableId << 20) + (aIndex << 2) + 1;

 	}

 TInt StringUtils::ValFromIndexF(TInt aIndex, TUint16 aTableId)

 	{

 	return (aTableId << 20) + (aIndex << 2) + 3;

 	}

 TInt StringUtils::ValFromIndex(TInt aIndex, TUint16 aTableId, TBool aCaseSensitive)

 	{

 	if (aCaseSensitive)

 		return ValFromIndex(aIndex, aTableId);

 	else

 		return ValFromIndexF(aIndex, aTableId);

 	}

 void  CStringPoolImplementation::AddCallBackL( MStringPoolCloseCallBack& aCallBack)

 	{

 	User::LeaveIfError(iCallBacks.Append(&aCallBack));

 	}