williamr@2: // Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@2: // 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
williamr@2: // which accompanies this distribution, and is available
williamr@2: // at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: // e32\include\memmodel\epoc\mmubase\kblockmap.h
williamr@2: // Kernel-side functionality for processing block maps
williamr@2: // 
williamr@2: //
williamr@2: 
williamr@2: #ifndef __KBLOCKMAP_H__
williamr@2: #define __KBLOCKMAP_H__
williamr@2: 
williamr@2: #include <e32ldr.h>
williamr@2: 
williamr@2: /**
williamr@2: The kernel-side representation of a block map.
williamr@2: */
williamr@2: class TBlockMap
williamr@2: 	{
williamr@2: public:
williamr@2: 	TBlockMap();
williamr@2: 	~TBlockMap();
williamr@2: 	
williamr@2: 	/**
williamr@2: 	Initialise and populate kernel-side representation from a user-side block map
williamr@2: 
williamr@2: 	@param aBlockMapInfo    	The user-side block map info structure.
williamr@2: 	
williamr@2: 	@param aBlockMapEntries 	Pointer to a buffer containg the user-side block map entries.
williamr@2: 	                            This object takes ownership of the buffer.
williamr@2: 	                        
williamr@2: 	@param aBlockMapEntriesSize The size of the user-side block map entries in bytes.
williamr@2: 
williamr@2: 	@param aReadUnitShift       Log2 of the paging device's read unit size.
williamr@2: 	
williamr@2: 	@param aDataLengthInFile 	The length of the (possibly compressed) code in the file.
williamr@2: 	*/
williamr@2: 	TInt Initialise(const SBlockMapInfoBase& aBlockMapInfo,
williamr@2: 					TBlockMapEntryBase* aBlockMapEntries,
williamr@2:                     TInt aBlockMapEntriesSize,
williamr@2: 					TInt aReadUnitShift,
williamr@2: 					TInt aDataLengthInFile);
williamr@2: 
williamr@2: 	/**
williamr@2: 	A function supplied to Read that is called to read the actual data.
williamr@2: 	
williamr@2: 	@param aArg1   		An argument parameter passed to read.
williamr@2: 	@param aArg2   		Another argument parameter passed to read.
williamr@2: 	@param aBuffer 		The address of the buffer to read the data into.
williamr@2: 	@param aBlockNumber The block number to read.
williamr@2: 	@param aBlockCount 	The number of blocks to read.
williamr@2: 	*/
williamr@2: 	typedef TInt (*TReadFunc)(TAny* aArg1, TAny* aArg2, TLinAddr aBuffer, TInt aBlockNumber, TInt aBlockCount);
williamr@2: 
williamr@2: 	/**
williamr@2: 	Read data from the file described by the block map into a buffer.
williamr@2: 
williamr@2: 	@param aBuffer   	  The buffer into which to read the data.
williamr@2: 	@param aPos	   	 	  The offset from the start of the data at which to read.
williamr@2: 	@param aLength   	  The length of data to read in bytes.
williamr@2: 	@param aReadUnitShift Log2 of the paging device's read unit size.
williamr@2: 	@param aReadFunc 	  The function to call to read the blocks of data.
williamr@2: 	@param aArg1   		  An argument parameter passed to read.
williamr@2: 	@param aArg2   		  Another argument parameter passed to read.
williamr@2: 	
williamr@2: 	@return The offset into the buffer at which the data starts, or one of the system-wide error
williamr@2: 	codes.
williamr@2: 	*/
williamr@2: 	TInt Read(TLinAddr aBuffer, TInt aPos, TInt aLength, TInt aReadUnitShift, TReadFunc aReadFunc, TAny* aArg1, TAny* aArg2) const;
williamr@2: 
williamr@2: 	/**
williamr@2: 	A contiguous area of media containing (possibly compressed) code.
williamr@2: 	*/
williamr@2: 	struct SExtent
williamr@2: 		{
williamr@2: 		TInt iDataOffset;		// position in file from, counting from start of code data
williamr@2: 		TUint iBlockNumber;		// block number containg this position
williamr@2: 		};
williamr@2: 
williamr@2: 	inline TInt Count() const;
williamr@2: 	inline const SExtent& Extent(TInt aIndex) const;
williamr@2: 	inline TInt DataLength() const;
williamr@2: 
williamr@2: 	/**
williamr@2: 	Print out the contents of this object for debugging purposes.
williamr@2: 	This method is only implemented in debug builds.
williamr@2: 	*/
williamr@2: 	void Dump() const;
williamr@2: 
williamr@2: private:
williamr@2: 	
williamr@2: 	TInt FindFirstExtent(TInt aPos) const;
williamr@2: 
williamr@2: private:
williamr@2: 
williamr@2: 	TInt iDataLength;
williamr@2: 	TInt iExtentCount;
williamr@2: 	SExtent* iExtents;
williamr@2: 	};
williamr@2: 
williamr@2: inline TInt TBlockMap::Count() const
williamr@2: 	{
williamr@2: 	return iExtentCount;
williamr@2: 	}
williamr@2: 
williamr@2: inline const TBlockMap::SExtent& TBlockMap::Extent(TInt aIndex) const
williamr@2: 	{
williamr@2: 	return iExtents[aIndex];
williamr@2: 	}
williamr@2: 
williamr@2: inline TInt TBlockMap::DataLength() const
williamr@2: 	{
williamr@2: 	return iDataLength;
williamr@2: 	}
williamr@2: 
williamr@2: #endif