/*

* Copyright (c) 2008-2009 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:    Store for singletons

*

*/

// INCLUDE FILES

#include "glxsingletonstore.h"

#include <glxlog.h>

// -----------------------------------------------------------------------------

// Constructor

// -----------------------------------------------------------------------------

//

CGlxSingletonStore::CGlxSingletonStore()

	{

    GLX_LOG_INFO("CGlxSingletonStore::CGlxSingletonStore");

	}

// -----------------------------------------------------------------------------

// return new instance

// -----------------------------------------------------------------------------

//

EXPORT_C CGlxSingletonStore* CGlxSingletonStore::InstanceLC()

	{

    CGlxSingletonStore* store = reinterpret_cast<CGlxSingletonStore*>(Dll::Tls());

    // Create new object, if one has not been created previously

    if ( !store )

        {

        store = new (ELeave) CGlxSingletonStore;

        // Store in tls pointer

        Dll::SetTls( reinterpret_cast<TAny*>(store));

        }

    // Push to cleanup stack - will make sure tls pointer is cleared if 

    // something leaves

    CleanupStack::PushL( TCleanupItem(&Cleanup, store) );

    return store;

	}

// -----------------------------------------------------------------------------

// Cleanup function

// -----------------------------------------------------------------------------

//

void CGlxSingletonStore::Cleanup( TAny* /*aStore*/ )

    {   

    // In case of one singleton owning another there can be nested calls to

    // CGlxSingletonStore::InstanceL, and so multiple Cleanup items on the

    // stack to delete the store.

    // Get the store pointer from TLS to ensure it hasn't already been deleted

    CGlxSingletonStore* obj

                    = reinterpret_cast<CGlxSingletonStore*>( Dll::Tls() );

    // Delete the object if instance was just created, and singleton

    // was _not_ successfully added

    if ( obj && obj->iSingletons.Count() == 0 ) 

        {

        delete obj;

        }   

    GLX_LOG_WARNING("Singleton factory function has (probably) left");

    }

// -----------------------------------------------------------------------------

// Destructor

// -----------------------------------------------------------------------------

//

EXPORT_C CGlxSingletonStore::~CGlxSingletonStore()

	{

    GLX_LOG_INFO("CGlxSingletonStore::~CGlxSingletonStore");

    // Delete remaining objects, if any

    TInt count = iSingletons.Count();

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

        {

        delete iSingletons[i].iObject;

        }

    // Close the singletons array

    iSingletons.Close();

    // Clear tls pointer

    Dll::SetTls( NULL );

	}

// -----------------------------------------------------------------------------

// Decrement reference count, and potentially delete object(s)

// -----------------------------------------------------------------------------

//

EXPORT_C void CGlxSingletonStore::Close(CBase* aObj)

    {

    CGlxSingletonStore* store = reinterpret_cast<CGlxSingletonStore*>(Dll::Tls());

    if ( store ) 

        {

        // Find an object by type

        TInt count = store->iSingletons.Count();

        TInt i = 0;

        while ( i < count ) 

            {

            TSingleton& singleton = store->iSingletons[i];

            if ( aObj == singleton.iObject )

                {

                // Found an existing object of type T

                // Remove reference

                singleton.iReferenceCount--;

                GLX_LOG_INFO2("CGlxSingletonStore::Close, Ref count %d, %x", singleton.iReferenceCount, singleton.iObject);

                // Delete object if no more references

                if ( !singleton.iReferenceCount )

                    {

                    store->iSingletons.Remove(i);

                    // Delete store object if last singleton

                    if ( store->iSingletons.Count() == 0 )

                    	{

                    	// CGlxSingletonStore destructor will clean up DLL's TLS pointer

                	    delete store;

                    	}

                    delete aObj;

                    }

                break;

                }

            i++;

            }

        }    

    else 

        {

        GLX_LOG_ERROR("CGlxSingletonStore::Close - Too many calls to Close()");

        }

    }