// Copyright (c) 2006-2009 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_file_cache.h

// 

//

/**

 @file

 @internalTechnology

*/

#if !defined(__SF_FILE_CACHE_H__)

#define __SF_FILE_CACHE_H__

#include "sf_cache_client.h"

//#define _DEBUG_READ_AHEAD

// if writing sequentially, start flushing dirty data when the cache is half full

//#define DOUBLE_BUFFERED_WRITING

NONSHARABLE_CLASS(CFileCache) : public CFsDispatchObject

	{

public:

	static CFileCache* NewL(CFileShare& aShare);

	CFileCache* ReNewL(CFileShare& aShare);

	~CFileCache();

	void Init(CFileShare& aShare);

	CMountCB& Mount() const;

	CFileCB* FileCB();

	void ReadAhead(CFsMessageRequest& aMsgRequest, TUint aMode);

	void ResetReadAhead();

	static TInt CompleteRead(CFsRequest* aMsgRequest);

	static TInt CompleteWrite(CFsRequest* aMsgRequest);

	TInt ReadBuffered(CFsMessageRequest& aMsgRequest, TUint aMode);

	TInt WriteBuffered(CFsMessageRequest& aMsgRequest, TUint aMode);

	inline TBool IsDirty() {return iDirtyDataOwner != NULL;}

	TInt FlushDirty(CFsRequest* aOldRequest = NULL);

	void Purge(TBool aPurgeDirty = EFalse);

	// from CFsObject

	void Close();

	inline TInt64 Size64() const {return iSize64;}

	// Sets 64 bit (cached) file size

	void SetSize64(TInt64 aSize);

	TDrive& Drive() const;

	TUint32 NameHash() const;

	HBufC& FileNameF() const;

    void MarkFileClean();

private:

	void ConstructL(CFileShare& aShare);

	CFileCache();

	void SetFileCacheFlags(CFileShare& aShare);

	TInt DoReadBuffered(CFsMessageRequest& aMsgRequest, TUint aMode, CFsClientMessageRequest*& aNewRequest);

	TInt DoWriteBuffered(CFsMessageRequest& aMsgRequest, CFsClientMessageRequest*& aNewRequest, TUint aMode);

	enum TFlushMode {EFlushSingle, EFlushHalf, EFlushAll};

	TInt DoFlushDirty(CFsClientMessageRequest*& aNewRequest, CFsRequest* aOldRequest, TFlushMode aFlushMode);

	inline TInt SegmentSize() const;

	inline TInt SegmentSizeLog2() const;

	inline TInt64 SegmentSizeMask() const;

	inline void UpdateSharePosition(CFsMessageRequest& aMsgRequest, TMsgOperation& aCurrentOperation);

	static TInt CompleteFlushDirty(CFsRequest* aMsgRequest);

	TInt FlushDirtySm(CFsMessageRequest& aMsgRequest);

	TInt AllocateRequest(CFsClientMessageRequest*& aNewRequest, TBool aWrite, CSessionFs* aSession = NULL);

	void DoReadAhead(CFsMessageRequest& aMsgRequest, TUint aMode);

	void FileDirty(CFsMessageRequest& aMsgRequest);

    TInt HandleWriteDirtyError(TInt aError);

	void PropagateFlushErrorToAllFileShares();

	static TInt ClosedTimerEvent(TAny* aFileCache);

	static TInt DirtyTimerEvent(TAny* aFileCache);

	TBool IsDriveThread();

private:

	CCacheClient* iCacheClient;

	TInt iMaxReadAheadLen;

	TInt iCacheSize;

	TInt32 iClosedFileKeepAliveTime;	// in microseconds

	TInt32 iDirtyDataFlushTime;			// in microseconds

	CFileCB* iFileCB;

	RFastLock iLock;

	TInt iFlushError;

	TBool iFlushBusy;

	CDriveThread* iDriveThread;

	TInt iDriveNum;

	// closed queue eject timer

	TThreadTimer iClosedTimer;

	// dirty data flush timer

	TThreadTimer iDirtyTimer;

	// The last session writing to this file. If non-NULL indicates cache contains dirty data

	CSessionFs* iDirtyDataOwner;

	// The size of the file.

	TInt64 iSize64;

	// The size of the file at the start of a write request

	TInt64 iInitialSize;

	// The full name of the file, including drive and extensions - Folded. This is "stolen" 

	// from the owning CFileCB when the CFileCB destructor calls CFileCache::Close().

	HBufC* iFileNameF;

	TUint32	iNameHash;

	TDrive* iDrive;

	CMountCB* iMount;

	// Read-ahead 

	TInt iSequentialReads;

	TInt iReadAheadLen;

	TInt64 iReadAheadPos;

	TInt64 iLastReadPos;

	TInt iLastReadLen;

	TBool iFileCacheReadAsync;

	CFsClientMessageRequest* iReadAheadRequest;

#ifdef DOUBLE_BUFFERED_WRITING

	// sequential append-write detection

	TInt iSequentialAppends;

#endif

	friend class TClosedFileUtils;

	friend class TFsFileWriteDirty;

	};

class TFileCacheSettings

	{

public:

	class TFileCacheConfig

		{

	public:

		TFileCacheConfig(TInt aDrive);

		static TFileCacheFlags ConvertEnumToFlags(const TInt aFileCacheRead, const TInt aFileCacheReadAhead, const TInt aFileCacheWrite);

	public:

		TInt iDrive;

		TFileCacheFlags iFlags;

		TBool iFileCacheReadAsync;

		TInt32 iFairSchedulingLen;			// in bytes

		TInt32 iCacheSize;					// in bytes

		TInt32 iMaxReadAheadLen;			// in bytes

		TInt32 iClosedFileKeepAliveTime;	// in microseconds

		TInt32 iDirtyDataFlushTime;			// in microseconds

		};

public:

	static TInt ReadPropertiesFile(TInt aDriveNumber);

	static void SetFlags(TInt aDrive, TFileCacheFlags alags);

	static TFileCacheFlags Flags(TInt aDrive);

	static TInt FileCacheReadAsync(TInt aDrive);

	static TInt FairSchedulingLen(TInt aDrive);

	static TInt MaxReadAheadLen(TInt aDrive);

	static TInt CacheSize(TInt aDrive);

	static TInt ClosedFileKeepAliveTime(TInt aDrive);

	static TInt DirtyDataFlushTime(TInt aDrive);

	static TInt GetFileCacheConfig(TInt aDrive, TFileCacheConfig*& aConfig);

private:

	static void Init();

	static void ReadEnum(const TDesC8& aSection, const TDesC8& aProperty, TInt32& aEnumVal, const TPtrC8* aEnumStrings);

private:

	static RArray<TFileCacheConfig>* iFileCacheSettings;

	};

class TClosedFileUtils

	{

public:

	static void InitL();

	static TInt Count();

	static CFileCache* At(TInt aIndex);

	static TBool IsClosed(CFileCache* aFileCache);

	static void AddL(CFileCache* aFileCache, TBool aLock);

	static void Remove();

	static void Remove(TInt aDrvNumber);

	static void Remove(CFileCache* aFileCache);

	static void Lock();

	static void Unlock();

	static void ReOpen(CFileCache* aFileCache, TBool aLock);

private:

	typedef TBool (*TTestFunc)(CFileCache& aFileCache, TAny* aVal);

	static void RemoveFiles(TTestFunc aTestFunc, TAny* aTestVal);

	static TBool TestDrive(CFileCache& aFileCache, TAny* aVal);

	static TBool TestFile(CFileCache& aFileCache, TAny* aVal);

private:

	static CFsObjectCon* iClosedFiles;

	};

#endif