userlibandfileserver/fileserver/sfile/sf_memory_man.h
author Mike Kinghan <mikek@symbian.org>
Tue, 16 Nov 2010 14:39:21 +0000
branchGCC_SURGE
changeset 303 9b85206a602c
parent 201 43365a9b78a3
child 257 3e88ff8f41d5
permissions -rw-r--r--
We need a way to pass flags to rombuilds in Raptor via extension flm interfaces, so that the CPP pass of the rom input files can be informed what toolchain we are building with and conditionally include or exclude files depending on whether the toolchain could build them.

// 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);

#if defined(_DEBUG) || defined(_DEBUG_RELEASE)
	void    SetMemoryLow(TBool aSetMemoryLow) {isMemoryLow = aSetMemoryLow;}; 
#endif //defined(_DEBUG) || defined(_DEBUG_RELEASE)

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 TInt32 CacheSize();
	static TInt32 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__)