// 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()

	{

	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)

	{

	TInt idx = iFree;

	if(idx < iSize)

		{

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

		iFree = entry.iNext;

		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)

	{

	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;

			}

		}

	}

/**

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;

	}