// Copyright (c) 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: Asynchronous allocation from the system shared buffer pool

//

#ifndef __SYSTEMSHAREDASYNCALLOC_H__

#define __SYSTEMSHAREDASYNCALLOC_H__

#include <es_commsbuf.h>

#include <elements/rworkerlock.h>

/**

Notifies the asyncronous request completion or error

@internalTechnology

*/

class MAsyncAllocNotifier 

	{

	public:

	virtual void OnCompletion() =0;

	virtual void OnError(TInt aError) =0;

	};

class CSystemSharedBufPool;

/**

Asynchronous allocation from the single system shared pool  

@internalTechnology

*/

NONSHARABLE_CLASS(CSystemSharedPoolAsyncAlloc) : public CActive

	{

	friend class CSystemSharedAsyncAlloc;

	public:

	CSystemSharedPoolAsyncAlloc(CSystemSharedBufPool& aPool, MAsyncAllocNotifier& aNotifer);	

	~CSystemSharedPoolAsyncAlloc();

	void Activate(TInt aFreeBufs);

	void Deactivate();

	private:

	// From CActive

	void RunL();

	TInt RunError(TInt aError);

	void DoCancel();

	private:

	CSystemSharedBufPool&	iPool;

	MAsyncAllocNotifier&	iNotifier;

	};

class CSystemSharedBufPool;

/**

Manages the asynchronous allocation from the system shared pools.

@internalTechnology

*/

NONSHARABLE_CLASS(CSystemSharedAsyncAlloc) : public CActive, public MAsyncAllocNotifier

	{

	enum TAsyncRequestState

	    {

	    EMakeRequest = 0,

	    ECancelRequest,

	    };

	public:

	static CSystemSharedAsyncAlloc* New(const RPointerArray<CSystemSharedBufPool>& aPools);

	~CSystemSharedAsyncAlloc();

	void StartRequest(CCommsBufAsyncRequest& aRequest);

	void CancelRequest(CCommsBufAsyncRequest& aRequest);

	private:

	CSystemSharedAsyncAlloc();

	TInt Construct(const RPointerArray<CSystemSharedBufPool>& aPools);	

	void MakePoolAsyncRequest();

	void MakePoolRequest();

	void CancelPoolAsyncRequest();

	void CancelAllPoolRequest();

	void ActivateSelf();

	void CompleteSelf();

	void CancelSelf();

   // From MAsyncAllocNotifier

    virtual void OnCompletion();

    virtual void OnError(TInt aError);  

    // From CActive

    void RunL();

    void DoCancel();

    void CompleteAsyncAllocs(); 

	private:

	RPointerArray<CSystemSharedPoolAsyncAlloc> 	iAsyncAllocPools;

	TAsyncRequestState                  iRequestState;

    RThread                             iOwnerThread;

    TBool                               iSignalled;

    RWorkerLock                         iAsynAllocLock;

    TDblQue<CCommsBufAsyncRequest>      iAllocsPending;     

	};

#endif // __SYSTEMSHAREDASYNCALLOC_H__