// 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 the License "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:

// f32\sfile\sf_memory_man.h

// 

//

/**

 @file

 @internalTechnology

*/

#if !defined(__SF_MEMORY_MAN_H__)

#define __SF_MEMORY_MAN_H__

#include <e32def.h>

const TUint KSegmentSizeLog2 = 12;

/**	Kernel's memory page size in bytes */

const TUint KSegmentSize = 1 << KSegmentSizeLog2;

/**	Forward declaration */

class CCacheMemoryClient;

/**	Cache memory manager class */

class CCacheMemoryManager : public CBase

	{

public:

	static CCacheMemoryManager* NewL(TInt aSizeInBytes);

	IMPORT_C CCacheMemoryClient* ConnectClientL(const TDesC& aClientName, TUint32 aMinSizeInSegs, TUint32 aMaxSizeInSegs);

	IMPORT_C TUint SegmentSizeInBytesLog2() const;

	TInt	RegisterClient(CCacheMemoryClient* aClient);

	TInt 	AllocateAndLockSegments(TUint8* aStartRamAddr, TInt aSegmentCount);

	TInt 	LockSegments(TUint8* aStartRamAddr, TUint32 aSegmentCount);

	TInt 	UnlockSegments(TUint8* aStartRamAddr, TUint32 aSegmentCount);

	TInt 	DecommitSegments(TUint8* aStartRamAddr, TUint32 aSegmentCount);

	TUint8* Base();

	void 	FreeMemoryChanged(TBool aIsMemoryLow);

private:

	~CCacheMemoryManager();

	CCacheMemoryManager(TUint32 aMaxSize);

	void 	ConstructL();

	TInt 	Lock(TUint8* aStartRamAddr, TInt aSegmentCount);

	TInt 	Unlock(TUint8* aStartRamAddr, TInt aSegmentCount);

	TInt	Commit(TUint8* aStartRamAddr, TInt aSegmentCountt);

	TInt 	Decommit(TUint8* aStartRamAddr, TInt aSegmentCount);

private:

	RChunk 	iChunk;					///< the RChunk interface to interact with demand paging sub-system

	TUint8* iBase;					///< the base ram address of the manager

	TUint32 iSizeInBytes;			///< virtual ram address size in bytes

	TUint32 iCurrentOffsetMark;		///< a flag in bytes to record current used virtual address space 

	TInt	iLowMemoryThreshold;	///< a threshold in bytes to flag the low memory condition, data type is aligned with TMemoryInfoV1::iTotalRamInBytes

	TBool	isMemoryLow;			///< the flag indicates low memory condition

	/**	an array holds all the registered clients */

	RPointerArray<CCacheMemoryClient> iRegisteredClients;

	friend class CCacheMemoryManagerFactory;

	};

/**

The factory class for CCacheMemoryManager

*/

class CCacheMemoryManagerFactory

	{

public:

	static void CreateL();

	static void Destroy();

	IMPORT_C static CCacheMemoryManager* CacheMemoryManager();

private:

	static CCacheMemoryManager* iCacheMemoryManager;

	};

/**

A static class to read cache memory manager settings

*/

NONSHARABLE_CLASS(TGlobalCacheMemorySettings)

	{

public:

	static void ReadPropertiesFile();

	static TInt CacheSize();

	static TInt LowMemoryThreshold();

private:

	static TInt32 iCacheSizeInBytes;

	static TInt32 iLowMemoryThreshold;

	};

/** Default cache memory size in KBytes (8192 KBytes)*/

const TInt 	KDefaultGlobalCacheMemorySize = (8 << 10);

/** 

Low memory threshold as a percentage of total RAM (10 %)

If the amount of RAM drops below this value, attempts to allocate memory will fail

*/

const TInt 	KDefaultLowMemoryThreshold = 10;

#endif	// !defined(__SF_MEMORY_MAN_H__)