// Copyright (c) 2008-2010 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:

 // SqlSvrObjContainer.inl

 // Should not be a template class!

 // Constructs an empty container.

 // 

 //

 template <class T> 

 RDbObjContainer<T>::RDbObjContainer() :

 	iEntries(NULL),

 	iSize(0),

 	iFree(0)

 	{

 	}

 /**

 Destroys the container and its content.

 */

 template <class T> 

 void RDbObjContainer<T>::Close()

 	{

 	if(iEntries)

 		{

 		for(/*RDbObjContainer<T>::*/TEntry* entry=iEntries;entry<(iEntries+iSize);++entry)

 			{

 			delete entry->iObj;

 			}

 		User::Free(iEntries);

 		iEntries = NULL;

 		}

 	iFree = iSize = 0;

 	}

 /**

 Ensures that the next attempt for adding a new object to the container won't fail because there 

 is no memory.

 (In other words - ensures that the container has at least one empty slot)

 @leave KErrNoMemory, an out of memory condition has occured;

 @panic SqlDb 7 In _DEBUG mode. Internal logic error.

 */

 template <class T> 

 void RDbObjContainer<T>::AllocL()

 	{

 	__ASSERT_DEBUG(iFree <= iSize, __SQLPANIC(ESqlPanicInternalError));

 	if(iFree == iSize)

 		{

 		if(iSize >= KMaxSize)

 			{

 			__SQLLEAVE(KErrNoMemory);

 			}

 		TInt size = iSize + RDbObjContainer<T>::KGranularity;

 		iEntries = (TEntry*)User::ReAllocL(iEntries, size * sizeof(TEntry));

 		iSize = size;

 		for(TInt i=iFree;i<size;)

 			{

 			/*RDbObjContainer<T>::*/TEntry& entry = iEntries[i];

 			entry.iObj = NULL;

 			entry.iNext = ++i;

 			}

 		}

 	}

 /**

 The method adds "aObj" pointer to the container.

 @param aObj A pointer to the object which will be stored in the container.

 @return Handle, uniquely identifying the stored object

 @panic SqlDb 4 In _DEBUG mode. aObj parameter is NULL.

 @panic SqlDb 7 In _DEBUG mode. Internal logic error.

 */

 template <class T> 

 TInt RDbObjContainer<T>::Add(T* aObj)

 	{

 	__ASSERT_DEBUG(aObj != NULL, __SQLPANIC(ESqlPanicBadArgument));

 	__ASSERT_DEBUG(iFree <= iSize, __SQLPANIC(ESqlPanicInternalError));

 	TInt idx = iFree;

 	if(idx < iSize)

 		{

 		/*RDbObjContainer<T>::*/TEntry& entry = iEntries[idx];

 		__ASSERT_DEBUG(!entry.iObj, __SQLPANIC(ESqlPanicInternalError));

 		iFree = entry.iNext;

 		__ASSERT_DEBUG(iFree <= iSize, __SQLPANIC(ESqlPanicInternalError));

 		entry.iObj = aObj;

 		return MakeHandle(idx);

 		}

 	return 0;

 	}

 /**

 @param aIndex Valid container index.

 @return Handle, uniquely identifying the object stored at aIndex index.

 */

 template <class T> 

 TInt RDbObjContainer<T>::MakeHandle(TInt aIndex) const

 	{

 	return aIndex + 1;

 	}

 /**

 @param aHandle Unique object handle

 @return Container index of the object, identified by aHandle parameter.

 */

 template <class T> 

 TInt RDbObjContainer<T>::MakeIndex(TInt aHandle) const

 	{

 	return aHandle - 1;

 	}

 /**

 Removes an object from the container.

 The removed object will be destroyed.

 @param aHandle Unique object handle

 @panic SqlDb 7 In _DEBUG mode. Internal logic error or there is no such object in the container.

 */

 template <class T> 

 void RDbObjContainer<T>::Remove(TInt aHandle)

 	{

 	__ASSERT_DEBUG(iFree <= iSize, __SQLPANIC(ESqlPanicInternalError));

 	if(aHandle > 0)	//It is a handle, sent by the client. It isn't a server's problem if the handle is <= 0.

 		{

 		TInt idx = MakeIndex(aHandle);

 		if(idx < iSize)

 			{

 			/*RDbObjContainer<T>::*/TEntry& entry = iEntries[idx];

 			delete entry.iObj;

 			entry.iObj = NULL;

 			entry.iNext = iFree;

 			iFree = idx;

 			}

 		}

 	__ASSERT_DEBUG(iFree <= iSize, __SQLPANIC(ESqlPanicInternalError));

 	}

 /**

 Looks up for an object in the container.

 @param aHandle Unique object handle

 @return A pointer to the found object or NULL.

 */

 template <class T> 

 T* RDbObjContainer<T>::Find(TInt aHandle) const

 	{

 	/*RDbObjContainer<T>::*/TEntry* entry = NULL;

 	if(aHandle > 0)	//It is a handle, sent by the client. It isn't a server's problem if the handle is <= 0.

 		{

 		TInt idx = MakeIndex(aHandle);

 		if(idx < iSize)

 			{

 			entry = &iEntries[idx];

 			}

 		}

 	return entry != NULL ? entry->iObj : NULL;

 	}

 /**

 Counts the alive objects in the container

 @return The object count

 */

 template <class T> 

 TInt RDbObjContainer<T>::Count() const

 	{

 	TInt count = 0;;

 	const /*RDbObjContainer::*/TEntry* const base = iEntries;

 	if(base)

 		{

 		for(const /*RDbObjContainer::*/TEntry* e=base+iSize;--e>=base;)

 			{

 			if(e->iObj)

 				{

 				++count;					

 				}

 			}

 		}

 	return count;

 	}