// Copyright (c) 1995-2009 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: 

// fileserver/sfsrv/clnotification.h

//

/**

 * @file

 * @internalTechnology

 * @released

 */

#ifndef __CLNOTIFICATION_H__

#define __CLNOTIFICATION_H__

#include "f32notification.h"

/* 

 * This comment is:

 * @internalTechnology

 * 

 * In general, the getter functions for TFsNotification extract data from a given buffer in the order:

 *  <Notification Size> <Path Length> <Type> <Path> [any sub-class members]

 * Notification of type EOverflow doesn't have a path associated with it

 * If a new name exists (ERename, EVolumeName and EDriveName) then the order is:

 *  <Notification Size> <Path Length> <New Name Length> <Type> <Path> <New Name>

 * For EAttribute the order is:

 *  <Notification Size> <Path Length> <Type> <Path> <Attribute>

 * For EFileChange the order is:

 *  <Notification Size> <Path Length> <Type> <Path> <File Size>

 */

/**

 * A Mask of all the valid filters that a client can set

 * @internalTechnology

 */

const TInt KNotificationValidFiltersMask = (TUint)(

		TFsNotification::EAttribute |

		TFsNotification::ECreate |

		TFsNotification::EDelete |

		TFsNotification::EDriveName | 

		TFsNotification::EFileChange |

		TFsNotification::EMediaChange |

		TFsNotification::ERename |

		TFsNotification::EVolumeName

		);

/*

 * Different notification types have different data associated with them.

 *  

 * All types have the following data and are aligned in the buffer like so:

 * Word1 : Size (TUint16 - upper 2 bytes) , NameLength (TUint16 - lower 2 bytes),

 * Word2 : Type (TUint - 4 bytes)

 * 

 @internalTechnology

 @released

 */

/*

 * This is the minimum allowed size of the buffer set by the client that is

 * equal to the size of a notification of maximum length and an overflow

 *

@internalTechnology

@released

*/

const TInt KMinNotificationBufferSize = 2*KNotificationHeaderSize + 2*KMaxFileName;

/**

 * Fill any dead space at the end of the buffer with this

 * If there is any dead space it should always be at least 1 word in size

 * @internalTechnology

 */

const TUint KNotificationBufferFiller = 0xFFFFFFFF;

class TFsNotification; //forward ref

/* This class is used as the buffer in the file server notifier framework.

 * 

 * The buffer itself is simply a descriptor.

 * 

 * This class is internal because we may wish to change the 

 * buffer mechanism in the future without BC breaks etc.

 * 

 * @internalTechnology

 */

class CFsNotificationList : public CBase

	{

public:

	static CFsNotificationList* NewL(TInt aBufferSize);

	virtual ~CFsNotificationList();

private:

	CFsNotificationList();

	const TFsNotification * NextNotification();

	TInt BufferSize() const;

	HBufC8* iBuf;			//Heap based to allow buffer size spec at runtime

	TInt iHead; 			//offset to the head of the readable data.

	TInt iTail;				//offset to end of the readable data.

	TPckg<TInt> iTailPckg;	//stores iTail, used in Asyc IPC

	TPtr8 iBufferPtr;		//stores iBuf->Ptr, used in Asyc IPC

	friend class RFsNotify;

	friend class CFsNotify;

	}; 

/**

 * @internalTechnology

 */

class RFsNotify : public RSubSessionBase

	{

	public:

		TInt Open(RFs& aFs,CFsNotificationList* aBuffer, TRequestStatus& aBufferStatus);

		void Close();

		//[Re]Issues notification request

		void RequestNotifications(TRequestStatus& aStatus, TPckg<TInt>& aTailPckg);

		TInt CancelNotifications();

		TInt AddNotification(TUint aNotificationType, const TDesC& aPath,  const TDesC& aFilename);

		TInt RemoveNotifications();

	}; 

/**

 * @internalTechnology

 *

 * This class is the iBody of CFsNotify. It is being used to shield the client from the internals which are being stored here.

 *

 * @see CFsNotify

 */

class CFsNotifyBody : public CBase

	{

public:

	virtual ~CFsNotifyBody();

private:

	CFsNotifyBody();

	TRequestStatus iBufferStatus;	//for server->buffer updates

	TRequestStatus* iClientStatus;	//Client's TRS:for receiving notification

	CFsNotificationList* iBuffer;	//Buffer into which the server puts the notifications

	RFsNotify iFsNotify;

	friend class CFsNotify;

	};

#endif //__CLNOTIFICATION_H__