// 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 "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members

 // which accompanies this distribution, and is available

 // at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".

 //

 // Initial Contributors:

 // Nokia Corporation - initial contribution.

 //

 // Contributors:

 //

 // Description:

 // e32\include\memmodel\epoc\mmubase\kblockmap.h

 // Kernel-side functionality for processing block maps

 // 

 //

 #ifndef __KBLOCKMAP_H__

 #define __KBLOCKMAP_H__

 #include <e32ldr.h>

 /**

 The kernel-side representation of a block map.

 */

 class TBlockMap

 	{

 public:

 	TBlockMap();

 	~TBlockMap();

 	/**

 	Initialise and populate kernel-side representation from a user-side block map

 	@param aBlockMapInfo    	The user-side block map info structure.

 	@param aBlockMapEntries 	Pointer to a buffer containg the user-side block map entries.

 	                            This object takes ownership of the buffer.

 	@param aBlockMapEntriesSize The size of the user-side block map entries in bytes.

 	@param aReadUnitShift       Log2 of the paging device's read unit size.

 	@param aDataLengthInFile 	The length of the (possibly compressed) code in the file.

 	*/

 	TInt Initialise(const SBlockMapInfoBase& aBlockMapInfo,

 					TBlockMapEntryBase* aBlockMapEntries,

                     TInt aBlockMapEntriesSize,

 					TInt aReadUnitShift,

 					TInt aDataLengthInFile);

 	/**

 	A function supplied to Read that is called to read the actual data.

 	@param aArg1   		An argument parameter passed to read.

 	@param aArg2   		Another argument parameter passed to read.

 	@param aBuffer 		The address of the buffer to read the data into.

 	@param aBlockNumber The block number to read.

 	@param aBlockCount 	The number of blocks to read.

 	*/

 	typedef TInt (*TReadFunc)(TAny* aArg1, TAny* aArg2, TLinAddr aBuffer, TInt aBlockNumber, TInt aBlockCount);

 	/**

 	Read data from the file described by the block map into a buffer.

 	@param aBuffer   	  The buffer into which to read the data.

 	@param aPos	   	 	  The offset from the start of the data at which to read.

 	@param aLength   	  The length of data to read in bytes.

 	@param aReadUnitShift Log2 of the paging device's read unit size.

 	@param aReadFunc 	  The function to call to read the blocks of data.

 	@param aArg1   		  An argument parameter passed to read.

 	@param aArg2   		  Another argument parameter passed to read.

 	@return The offset into the buffer at which the data starts, or one of the system-wide error

 	codes.

 	*/

 	TInt Read(TLinAddr aBuffer, TInt aPos, TInt aLength, TInt aReadUnitShift, TReadFunc aReadFunc, TAny* aArg1, TAny* aArg2) const;

 	/**

 	A contiguous area of media containing (possibly compressed) code.

 	*/

 	struct SExtent

 		{

 		TInt iDataOffset;		// position in file from, counting from start of code data

 		TUint iBlockNumber;		// block number containg this position

 		};

 	inline TInt Count() const;

 	inline const SExtent& Extent(TInt aIndex) const;

 	inline TInt DataLength() const;

 	/**

 	Print out the contents of this object for debugging purposes.

 	This method is only implemented in debug builds.

 	*/

 	void Dump() const;

 private:

 	TInt FindFirstExtent(TInt aPos) const;

 private:

 	TInt iDataLength;

 	TInt iExtentCount;

 	SExtent* iExtents;

 	};

 inline TInt TBlockMap::Count() const

 	{

 	return iExtentCount;

 	}

 inline const TBlockMap::SExtent& TBlockMap::Extent(TInt aIndex) const

 	{

 	return iExtents[aIndex];

 	}

 inline TInt TBlockMap::DataLength() const

 	{

 	return iDataLength;

 	}

 #endif