/*

* 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: 

* This class represents the boot sector of a FAT32 image. 

* This class is derived from basebootsector class which is constitutes 

* the common boot sector fields for FAT16 and FAT32 class. 

* @internalComponent

* @released

*

*/

#include "fat32bootsector.h"

#include <cstring>

/**

Constructor of the fat16 boot sector class

@internalComponent

@released

*/

TFAT32BootSector::TFAT32BootSector()

{

}

/**

Destructor of the fat16 boot sector class

@internalComponent

@released

*/

TFAT32BootSector::~TFAT32BootSector()

{

}

/**

Set the file system type

@internalComponent

@released

*/

void TFAT32BootSector::SetFileSysType()

{

	strcpy(reinterpret_cast<char*>(iFileSysType),"FAT32   ");

}

//Number of entries allowed in the root directory, specific to Fat12/16, zero for FAT32

void TFAT32BootSector::SetRootDirEntries()

{

	iRootDirEntries = KFat32RootDirEntries;;		

}

//Sets the number of reserved sectors on the volume

void TFAT32BootSector::SetReservedSectors()

{

	iReservedSectors = KDefaultFat32ReservedSectors;

}

/**

Set the sectors per cluster ratio

@internalComponent

@released

@param aPartitionSize partition size in bytes

*/

void TFAT32BootSector::ComputeSectorsPerCluster(Long64 aPartitionSize)

{

	if (aPartitionSize > K32GB)

	{

		iSectorsPerCluster = K64SectorsPerCluster;	

	}

	else if(aPartitionSize > K16GB)

	{

		iSectorsPerCluster = K32SectorsPerCluster;

	}

	else if(aPartitionSize > K8GB)

	{

		iSectorsPerCluster = K16SectorsPerCluster;

	}

	else if ( aPartitionSize > K260MB)

	{

		iSectorsPerCluster = K8SectorsPerCluster;	

	}

	else 

	{

		iSectorsPerCluster = K1SectorsPerCluster;

	}

}

/**

Set the sectors per cluster ratio

To refer this mathematical computation, Please see:

Microsoft Extensible Firmware Initiative FAT32 File System 

Specification document

@internalComponent

@released

@param aPartitionSize partition size in bytes

*/

void TFAT32BootSector::ComputeFatSectors(Long64 aPartitionSize)

{

	int iRootDirSectors = ((iRootDirEntries*32) + (iBytesPerSector - 1)) / iBytesPerSector;

	int Log2OfBytesPerSector = Log2(iBytesPerSector);

	Long64 TotalSectors64 = aPartitionSize >> Log2OfBytesPerSector;

	Long64 tmpval1 = TotalSectors64 - (iReservedSectors + iRootDirSectors);

	Long64 tmpval2 =(256 * iSectorsPerCluster) + iNumberOfFats;

	tmpval2 = tmpval2 / 2;

	Long64 FatSectors = (tmpval1 + (tmpval2 - 1)) / tmpval2;

	iFatSectors = 0;

	iFatSectors32 = (unsigned int)FatSectors;

}

/**

Sets the Fat flags

@internalComponent

@released

*/

void TFAT32BootSector::SetExtFlags()

{

	iExtFlags = KDefaultExtFlags;

}

/**

Returns the Fat flags

@internalComponent

@released

@return fat flags

*/

unsigned short TFAT32BootSector::ExtFlags()

{

	return iExtFlags;

}

/**

Sets the version number of the file system

@internalComponent

@released

*/

void TFAT32BootSector::SetFileSystemVersion()

{

	iFileSystemVersion = KDefaultVersion;

}

/**

Returns the version number of the file system

@internalComponent

@released

@return file system version

*/

unsigned short TFAT32BootSector::FileSystemVersion()

{

	return iFileSystemVersion;

}

/**

Sets the cluster number of the root directory

@internalComponent

@released

*/

void TFAT32BootSector::SetRootCluster()

{

	iRootCluster = KDefaultRootDirClusterNumber;

}

/**

Returns the cluster number of the root directory

@internalComponent

@released

@return cluster number allocated to root directory,usually 2.

*/

unsigned int TFAT32BootSector::RootCluster()

{

	return iRootCluster;

}

/**

Set the sector number containing the FSIInfo structure

@internalComponent

@released

*/

void TFAT32BootSector::SetFSInfo()

{

	iFSInfo = KDefaultFSInfoSector;

}

/**

Returns  the sector number containing the FSIInfo structure

@internalComponent

@released

@return FSInfo structure

*/

unsigned short TFAT32BootSector::FSInfo()

{

	return iFSInfo;

}

/**

Set the backup boot sector

@internalComponent

@released

*/

void TFAT32BootSector::SetBackUpBootSector()

{

	iBackUpBootSector = KDefaultBkUpBootSec;

}

/**

Returns the backup boot sector

@internalComponent

@released

@return backup boot sector

*/

unsigned  short TFAT32BootSector::BackUpBootSector()

{

	return iBackUpBootSector;

}

/**

Reserved for future expansion. Code that formats FAT32 volumes should always 

set all of the bytes of this field to 0.

@internalComponent

@released

*/

void TFAT32BootSector::SetFutureReserved()

{

	for(int i = 0;i < KMaxSizeFutureExpansion;i++)

	iFutureReserved[i] = 0;

}

/**

Returns field value reserved for future expansion

@internalComponent

@released

@return zero as this field is initialized to null value here

*/

unsigned char* TFAT32BootSector::FutureReserved()

{

	return iFutureReserved;

}

/**Returns the file system type

@internalComponent

@released

@return file system type

*/

unsigned char* TFAT32BootSector::FileSysType()

{

	return iFileSysType;

}