userlibandfileserver/fileserver/sfat32/sl_fatmisc32.cpp
changeset 0 a41df078684a
child 20 597aaf25e343
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/userlibandfileserver/fileserver/sfat32/sl_fatmisc32.cpp	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,896 @@
+// Copyright (c) 1996-2009 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\sfat\sl_fatmisc32.cpp
+// 
+//
+
+#include "sl_std.h"
+#include "sl_cache.h"
+
+/**
+@return ETrue if it is Fat32
+*/
+TBool CFatFormatCB::Is32BitFat() const
+	{
+	return(iFileSystemName==KFileSystemName32);
+	}
+
+/**
+@return ETrue if it is Fat16
+*/
+TBool CFatFormatCB::Is16BitFat() const
+	{
+    return(iFileSystemName==KFileSystemName16);
+    }
+
+/**
+Calculate the FAT size in sectors for a Fat32 volume
+
+@return The number of sectors
+*/
+TUint32 CFatFormatCB::MaxFat32Sectors() const
+	{
+	TUint32 calc1 = iMaxDiskSectors - iReservedSectors;
+	TUint32 calc2 = (256 * iSectorsPerCluster) + iNumberOfFats;
+	calc2 = calc2 >> 1;
+	return (calc1 + (calc2 - 1))/calc2;
+	}
+
+
+const TUint KDefFatResvdSec = 1;    ///< default number of FAT12/16 reserved sectors
+const TUint KDefFat32ResvdSec = 32; ///< default number of FAT32 reserved sectors
+
+//-------------------------------------------------------------------------------------------------------------------
+void Dump_TLDFormatInfo(const TLDFormatInfo& aInfo)
+{
+    (void)aInfo;
+#ifdef _DEBUG
+    __PRINT(_L("----- TLDFormatInfo dump:"));
+    __PRINT1(_L("iCapacity:%d"), aInfo.iCapacity);
+    __PRINT1(_L("iSectorsPerCluster:%d"), aInfo.iSectorsPerCluster);
+    __PRINT1(_L("iSectorsPerTrack:%d"), aInfo.iSectorsPerTrack);
+    __PRINT1(_L("iFATBits:%d"), aInfo.iFATBits);
+    __PRINT1(_L("iReservedSectors:%d"), aInfo.iReservedSectors);
+    __PRINT1(_L("iFlags:%d"), aInfo.iFlags);
+    __PRINT(_L("-----"));
+#endif
+}
+
+//-------------------------------------------------------------------------------------------------------------------
+
+/**
+Initialize the format parameters for a normal fixed sized disk
+Setting set to adhere to Rules of Count of clusters for FAT type
+
+@param  aDiskSizeInSectors Size of volume in sectors
+@return system-wide error code
+*/
+TInt  CFatFormatCB::InitFormatDataForFixedSizeDiskNormal(TInt aDiskSizeInSectors, const TLocalDriveCapsV6& aCaps)
+	{
+	__PRINT1(_L("CFatFormatCB::InitFormatDataForFixedSizeDiskNormal() sectors:%d"), aDiskSizeInSectors);
+    
+    if( Drive().IsRemovable() )
+		iNumberOfFats = KNumberOfFatsExternal;
+	else
+		iNumberOfFats = KNumberOfFatsInternal;	
+ 	
+	iReservedSectors=KDefFatResvdSec;		
+	if (aDiskSizeInSectors <=4084*1)	// 2MB
+		{
+		iRootDirEntries=128;
+		iSectorsPerCluster=1;
+		iFileSystemName=KFileSystemName12;
+		iSectorsPerFat=MaxFat12Sectors();
+   		}
+	else if (aDiskSizeInSectors<4084*2) // < 4MB (8168 sectors)
+		{
+		iRootDirEntries=256; 
+		iSectorsPerCluster=2;
+		iFileSystemName=KFileSystemName12;
+		iSectorsPerFat=MaxFat12Sectors();
+		}
+	else if (aDiskSizeInSectors<4084*4) // < 8MB (16336 sectors)
+		{
+		iRootDirEntries=512;
+		iSectorsPerCluster=4;
+		iFileSystemName=KFileSystemName12;
+		iSectorsPerFat=MaxFat12Sectors();
+		}
+	else if (aDiskSizeInSectors<4084*8) // < 16MB (32672 sectors)
+		{
+		iRootDirEntries=512;
+		iSectorsPerCluster=8;
+		iFileSystemName=KFileSystemName12;
+		iSectorsPerFat=MaxFat12Sectors();
+		}
+	else if(aDiskSizeInSectors<1048576) // >= 16Mb - FAT16   < (1048576) 512MB
+		{
+		iFileSystemName=KFileSystemName16;
+		TInt minSectorsPerCluster=(aDiskSizeInSectors+KMaxFAT16Entries-1)/KMaxFAT16Entries;
+		iRootDirEntries=512;
+		iSectorsPerCluster=1;
+		while (minSectorsPerCluster>iSectorsPerCluster)
+			iSectorsPerCluster<<=1;
+		iSectorsPerFat=MaxFat16Sectors();
+		}
+	else	//use FAT32
+		{
+		iFileSystemName=KFileSystemName32;
+		iRootDirEntries=0;						//this is always the case for fat32
+		if(aDiskSizeInSectors < 16777216)		//8GB in 512byte sectors
+			iSectorsPerCluster=8;
+		else if(aDiskSizeInSectors < 33554432)	//16GB in 512byte sectors
+			iSectorsPerCluster=16;
+		else if(aDiskSizeInSectors < 67108864)	//32GB in 512byte sectors 
+			iSectorsPerCluster=32;
+		else
+			iSectorsPerCluster=64;				//Anything >= 32GB uses a 32K cluster size
+		iReservedSectors=KDefFat32ResvdSec;
+		iRootClusterNum=2;						//As recomended in the document
+		iSectorsPerFat=MaxFat32Sectors();
+		
+		}
+
+	// Ensure cluster size is a multiple of the block size
+	TInt blockSizeInSectors = aCaps.iBlockSize >> iSectorSizeLog2;
+	__PRINT1(_L("blockSizeInSectors: %d"),blockSizeInSectors);
+	ASSERT(blockSizeInSectors == 0 || IsPowerOf2(blockSizeInSectors));
+	if (blockSizeInSectors != 0 && IsPowerOf2(blockSizeInSectors))
+		{
+		__PRINT1(_L("iSectorsPerCluster	(old): %d"),iSectorsPerCluster);
+		AdjustClusterSize(blockSizeInSectors);
+		__PRINT1(_L("iSectorsPerCluster	(new): %d"),iSectorsPerCluster);
+		}
+
+	// Align first data sector on an erase block boundary if
+	// (1) the iEraseBlockSize is specified
+	// (2) the start of the partition is already aligned to an erase block boundary, 
+	//     i.e. iHiddenSectors is zero or a multiple of iEraseBlockSize
+	__PRINT1(_L("iHiddenSectors: %d"),iHiddenSectors);
+	TInt eraseblockSizeInSectors = aCaps.iEraseBlockSize >> iSectorSizeLog2;
+	__PRINT1(_L("eraseblockSizeInSectors: %d"),eraseblockSizeInSectors);
+	ASSERT(eraseblockSizeInSectors == 0 || IsPowerOf2(eraseblockSizeInSectors));	
+	ASSERT(eraseblockSizeInSectors == 0 || eraseblockSizeInSectors >= blockSizeInSectors);
+	if ((eraseblockSizeInSectors != 0) &&
+		(iHiddenSectors % eraseblockSizeInSectors == 0) &&	
+		(IsPowerOf2(eraseblockSizeInSectors)) &&
+		(eraseblockSizeInSectors >= blockSizeInSectors))
+		{
+		TInt r = AdjustFirstDataSectorAlignment(eraseblockSizeInSectors);
+		ASSERT(r == KErrNone);
+		(void) r;
+		}
+	__PRINT1(_L("iReservedSectors: %d"),iReservedSectors);
+	__PRINT1(_L("FirstDataSector: %d"), FirstDataSector());
+
+    return KErrNone;
+	}
+
+TInt CFatFormatCB::FirstDataSector() const
+	{
+	TInt rootDirSectors = (iRootDirEntries * KSizeOfFatDirEntry + (iBytesPerSector-1)) / iBytesPerSector;
+    return iHiddenSectors + iReservedSectors + iNumberOfFats*iSectorsPerFat + rootDirSectors;
+	}
+
+void CFatFormatCB::AdjustClusterSize(TInt aRecommendedSectorsPerCluster)
+	{
+    const TInt KMaxSecPerCluster = 64;	// 32K
+	while (aRecommendedSectorsPerCluster > iSectorsPerCluster && iSectorsPerCluster <= (KMaxSecPerCluster/2))
+		iSectorsPerCluster<<= 1;
+	}
+
+// AdjustFirstDataSectorAlignment()
+// Attempts to align the first data sector on an erase block boundary by modifying the
+// number of reserved sectors.
+TInt CFatFormatCB::AdjustFirstDataSectorAlignment(TInt aEraseBlockSizeInSectors)
+	{
+	const TBool bFat16 = Is16BitFat();
+    const TBool bFat32 = Is32BitFat();
+
+	// Save these 2 values in the event of a convergence failure; this should 
+	// hopefully never happen, but we will cater for this in release mode to be safe,
+	TInt reservedSectorsSaved = iReservedSectors;
+	TInt sectorsPerFatSaved = iSectorsPerFat;
+
+	TInt reservedSectorsOld = 0;
+
+	// zero for FAT32
+	TInt rootDirSectors = (iRootDirEntries * KSizeOfFatDirEntry + (iBytesPerSector-1)) / iBytesPerSector;
+	TInt fatSectors = 0;
+
+	TInt KMaxIterations = 10;
+	TInt n;
+	for (n=0; n<KMaxIterations && reservedSectorsOld != iReservedSectors; n++)
+		{
+		reservedSectorsOld = iReservedSectors;
+
+		iSectorsPerFat = bFat32 ? MaxFat32Sectors() : bFat16 ? MaxFat16Sectors() : MaxFat12Sectors();
+
+		fatSectors = iSectorsPerFat * iNumberOfFats;
+
+		// calculate number of blocks
+		TInt  nBlocks = (iReservedSectors + fatSectors + rootDirSectors + aEraseBlockSizeInSectors-1) / aEraseBlockSizeInSectors;
+
+		iReservedSectors = (nBlocks * aEraseBlockSizeInSectors) - rootDirSectors - fatSectors;
+		}
+	
+	ASSERT(iReservedSectors >= (TInt) (bFat32 ? KDefFat32ResvdSec : KDefFatResvdSec));
+
+	if ((FirstDataSector() & (aEraseBlockSizeInSectors-1)) == 0)
+		{
+		return KErrNone;
+		}
+	else
+		{
+		iReservedSectors = reservedSectorsSaved;
+		iSectorsPerFat = sectorsPerFatSaved;
+		return KErrGeneral;
+		}
+	}
+
+
+//-------------------------------------------------------------------------------------------------------------------
+
+/**
+Create the boot sector on media for the volume. For FAT32 also creates a backup copy of the boot sector.
+
+@leave System wide error codes
+*/
+void CFatFormatCB::CreateBootSectorL()
+	{
+	__PRINT1(_L("CFatFormatCB::CreateBootSector() drive:%d"),DriveNumber());
+
+	
+    const TBool bFat32 = Is32BitFat();
+    
+    TFatBootSector bootSector;
+
+	bootSector.SetVendorID(KDefaultVendorID);
+	bootSector.SetBytesPerSector(iBytesPerSector);
+	bootSector.SetSectorsPerCluster(iSectorsPerCluster);
+	bootSector.SetReservedSectors(iReservedSectors);
+	bootSector.SetNumberOfFats(iNumberOfFats);
+	iCountOfClusters=iMaxDiskSectors/iSectorsPerCluster;
+	if (!bFat32)
+		{
+		if (iCountOfClusters>(TInt)KMaxTUint16)
+			User::Leave(KErrTooBig);
+		}
+
+	bootSector.SetReservedByte(0);
+	TTime timeID;
+	timeID.HomeTime();						//	System time in future?
+	bootSector.SetUniqueID(I64LOW(timeID.Int64()));	//	Generate UniqueID from time
+	bootSector.SetVolumeLabel(_L8(""));
+	bootSector.SetFileSysType(iFileSystemName);
+// Floppy specific info:
+	bootSector.SetJumpInstruction();
+	bootSector.SetMediaDescriptor(KBootSectorMediaDescriptor);
+	bootSector.SetNumberOfHeads(iNumberOfHeads);
+	bootSector.SetHiddenSectors(iHiddenSectors);
+	bootSector.SetSectorsPerTrack(iSectorsPerTrack);
+	bootSector.SetPhysicalDriveNumber(128);
+	bootSector.SetExtendedBootSignature(0x29);
+
+	if(bFat32)
+		{
+		bootSector.SetFatSectors(0);
+		bootSector.SetFatSectors32(iSectorsPerFat);
+		bootSector.SetRootDirEntries(0);
+		bootSector.SetTotalSectors(0);
+		bootSector.SetHugeSectors(iMaxDiskSectors);
+		bootSector.SetFATFlags(0);			
+		bootSector.SetVersionNumber(0x00);	
+		bootSector.SetRootClusterNum(iRootClusterNum);
+		bootSector.SetFSInfoSectorNum(KFSInfoSectorNum);	
+        bootSector.SetBkBootRecSector(KBkBootSectorNum);
+		}
+	else//fat12 and 16
+		{
+		bootSector.SetFatSectors32(0);
+		bootSector.SetFatSectors(iSectorsPerFat);
+		bootSector.SetRootDirEntries(iRootDirEntries);
+
+		if (iMaxDiskSectors<=(TInt)KMaxTUint16)
+			{
+			bootSector.SetTotalSectors(iMaxDiskSectors);
+			bootSector.SetHugeSectors(0);
+			}
+		else
+			{
+			bootSector.SetTotalSectors(0);
+			bootSector.SetHugeSectors(iMaxDiskSectors);
+			}
+		}
+
+	//-- write main boot sector to the first sector on media
+    User::LeaveIfError(FatMount().DoWriteBootSector(KBootSectorNum*bootSector.BytesPerSector(), bootSector));
+	
+    //-- for FAT32 write backup copy of the boot sector
+    if(bFat32)
+        {
+        User::LeaveIfError(FatMount().DoWriteBootSector(KBkBootSectorNum*bootSector.BytesPerSector(), bootSector));    
+        }
+
+    }
+
+//-------------------------------------------------------------------------------------------------------------------
+
+/**
+Format a disk section, called iteratively to erase whole of media, on last iteration
+creates an empty volume. If called with quick formatonly erases the Fat leaving the
+rest of the volume intact.
+
+@leave System wide error code
+*/
+void CFatFormatCB::DoFormatStepL()
+	{
+	if (iFormatInfo.iFormatIsCurrent==EFalse)
+		{ // Only done first time through
+		if (iMode & EForceErase)
+			{
+			TInt r = FatMount().ErasePassword();
+			User::LeaveIfError(r);
+			// CFatMountCB::ErasePassword() calls TBusLocalDrive::ForceRemount(),
+			// so need to stop a remount from occurring in next call to :
+			// TFsFormatNext::DoRequestL((), TDrive::CheckMount().
+			FatMount().Drive().SetChanged(EFalse);
+			}
+
+        RecordOldInfoL();
+		InitializeFormatDataL();
+		FatMount().DoDismount();
+		if (iVariableSize)
+			FatMount().ReduceSizeL(0,I64LOW(FatMount().iSize));
+		}
+    //
+    // Blank disk if not EQuickFormat
+    //
+	if (!iVariableSize && !(iMode & EQuickFormat) && iCurrentStep)
+		{
+		if (iFormatInfo.iFormatIsCurrent == EFalse)
+			{//-- firstly invalidate sectors 0-6 inclusive, they may contain main boot sector, backup boot sector and FSInfo sector.
+	        DoZeroFillMediaL(0, (KBkBootSectorNum+1)*iBytesPerSector);
+            }
+		TInt ret=FatMount().LocalDrive()->Format(iFormatInfo);
+		if (ret!=KErrNone && ret!=KErrEof) // Handle format error
+            ret = HandleCorrupt(ret);
+
+        if (ret!=KErrNone && ret!=KErrEof) // KErrEof could be set by LocalDrive()->Format()
+		    User::Leave(ret);
+
+		if (ret==KErrNone)
+			{
+			iCurrentStep = I64LOW( 100 - (100 * TInt64(iFormatInfo.i512ByteSectorsFormatted)) / iMaxDiskSectors );
+			if (iCurrentStep<=0)
+				iCurrentStep=1;
+			return;
+			}
+		}
+
+	// ReMount since MBR may have been rewritten and partition may have moved / changed size
+	TInt ret = LocalDrive()->ForceRemount(0);
+	if (ret != KErrNone && ret != KErrNotSupported)
+		User::Leave(ret);
+
+	// MBR may have changed, so need to re-read iHiddenSectors etc.before BPB is written
+	InitializeFormatDataL();
+
+    // Translate bad sector number to cluster number which contains that sector
+    // This only happens in full format, in quick format they are already cluster numbers
+    if (!iVariableSize && !(iMode & EQuickFormat))
+        User::LeaveIfError(BadSectorToCluster());
+
+	//Check if root cluster is bad and update as required
+	if(Is32BitFat() && !iVariableSize && (iMode & EQuickFormat))
+		{
+		if(iBadClusters.Find(iRootClusterNum) !=  KErrNotFound)
+			{
+			iRootClusterNum++;
+            while(iBadClusters.Find(iRootClusterNum) != KErrNotFound)
+				{
+				iRootClusterNum++;
+				}
+			}
+		}
+
+    //
+    // Do the rest of the disk in one lump
+    //
+	iCurrentStep=0;
+
+    //-- zero-fill media from position 0 to the FAT end, i.e main & backup boot sector, FSInfo and its copy and all FATs
+    const TUint32 posFatEnd = ((iSectorsPerFat*iNumberOfFats) + iReservedSectors) * iBytesPerSector; //-- last FAT end position
+	
+    if (iVariableSize)
+		FatMount().EnlargeL(posFatEnd); 
+
+    DoZeroFillMediaL(0, posFatEnd);
+    
+    if(Is32BitFat())
+		{//create an empty root directory entry here
+		
+        const TUint KFat32EntrySz = 4; //-- FAT32 entry size, bytes
+        const TInt  startFAT1   = iReservedSectors;              //-- FAT1 start sector
+        const TInt  entryOffset = iRootClusterNum*KFat32EntrySz; //-- Root dir entry offset in the FAT, bytes
+
+		TBuf8<KFat32EntrySz> EOF(KFat32EntrySz);
+		EOF[0]=0xFF;		
+		EOF[1]=0xFF;
+		EOF[2]=0xFF;
+		EOF[3]=0x0F;
+
+        //-- write EOF mark to the every FAT copy
+    	for(TInt i=0; i<iNumberOfFats; i++)
+            {
+		    const TInt rootDirEntryPos = iBytesPerSector*(startFAT1 + i*iSectorsPerFat) + entryOffset;
+            User::LeaveIfError(LocalDrive()->Write(rootDirEntryPos, EOF));
+            }
+
+        //-- zero-fill FAT32 root directory (just 1 cluster)
+		const TInt firstDataSector = iReservedSectors + (iNumberOfFats * iSectorsPerFat); //+RootDirSectors (not required for fat32)
+        const TInt firstSectorOfCluster = ((iRootClusterNum - KFatFirstSearchCluster) * iSectorsPerCluster) + firstDataSector;
+	
+        const TUint32 posRootDirStart = firstSectorOfCluster * iBytesPerSector;
+        const TUint32 posRootDirEnd = posRootDirStart + iSectorsPerCluster*iBytesPerSector;
+
+        DoZeroFillMediaL(posRootDirStart, posRootDirEnd);
+        }
+	else
+		{//-- FAT12/16
+		    //-- Zero fill root directory
+            const TInt rootDirSector = iReservedSectors + (iNumberOfFats * iSectorsPerFat); 
+            const TInt rootDirSize   = iRootDirEntries * KSizeOfFatDirEntry; //-- size in bytes
+            
+            const TUint32 posRootDirStart = rootDirSector * iBytesPerSector;
+            const TUint32 posRootDirEnd   = posRootDirStart + rootDirSize;
+
+            const TInt numOfRootSectors=(rootDirSize%iBytesPerSector) ? (rootDirSize/iBytesPerSector+1) : (rootDirSize/iBytesPerSector);
+		    if (iVariableSize)
+			    FatMount().EnlargeL(iBytesPerSector*numOfRootSectors);
+
+            DoZeroFillMediaL(posRootDirStart, posRootDirEnd);
+
+		// Enlarge ram drive to take into account rounding of
+		// data start to cluster boundary
+		if(iVariableSize && iSectorsPerCluster!=1)
+			{
+			const TInt firstFreeSector=rootDirSector+numOfRootSectors;
+			const TInt firstFreeCluster=firstFreeSector%iSectorsPerCluster ? firstFreeSector/iSectorsPerCluster+1 : firstFreeSector/iSectorsPerCluster;
+			const TInt alignedSector=firstFreeCluster*iSectorsPerCluster;
+			if(alignedSector!=firstFreeSector)
+				FatMount().EnlargeL((alignedSector-firstFreeSector)*iBytesPerSector);
+			}
+		}
+
+    //-- FAT[0] must contain media descriptor in the low byte, FAT[1] for fat16/32 may contain some flags
+	TBuf8<8> startFat(8);
+    startFat.Fill(0xFF);
+   
+    if(Is32BitFat()) //-- FAT32
+        {//-- FAT32 uses only low 28 bits in FAT entry. 
+        startFat[3] = 0x0F;
+        startFat[7] = 0x0F;
+        } 
+    else if(iVariableSize||Is16BitFat()) //-- FAT16 or RAM drive which is always FAT16
+        {
+        startFat.SetLength(4);
+        }
+    else //-- FAT12
+        {
+        startFat.SetLength(3);
+        }
+
+    startFat[0]=KBootSectorMediaDescriptor;
+
+    //-- write FAT[0] and FAT[1] entries to all copies of FAT
+	for(TInt i=0;i<iNumberOfFats;i++)
+        {
+		User::LeaveIfError(LocalDrive()->Write(iBytesPerSector*(iReservedSectors+(iSectorsPerFat*i)),startFat));
+        }
+
+	//-- create boot sectors
+    CreateBootSectorL();
+
+    //-- create FSInfo sectors
+    if (Is32BitFat())
+		{
+		CreateReservedBootSectorL();
+        CreateFSInfoSectorL();
+		}
+
+    //-- here we have bad clusters numbers saved by the quick format
+    //-- Interpret old bad cluster number to new cluster number and mark new bad clusters
+    if (!iVariableSize && iBadClusters.Count()>0)
+        {
+ 	
+        //-- Here we need fully mounted volume, so mount it normally.
+	    FatMount().MountL(EFalse);
+
+        iBadClusters.Sort();
+        TranslateL();
+        const TInt mark = FatMount().Is32BitFat() ? KBad_32Bit : (FatMount().Is16BitFat() ? KBad_16Bit : KBad_12Bit);
+        
+        for (TInt i=0; i<iBadClusters.Count(); ++i)
+            FatMount().FAT().WriteL(iBadClusters[i], mark);
+        
+        FatMount().FAT().FlushL();
+        
+        //-- indicate that the volume is "dirty" in order to the next Mount evend not to use FSInfo, which
+        //-- contains incorrect value of free clusters because we already have bad ones saved.  
+        //-- This is a very rare condition.
+        FatMount().SetVolumeCleanL(EFalse); 
+
+#if defined(_DEBUG)
+	TInt r=FatMount().CheckDisk();
+	__PRINT1(_L("CFatFormatCB::DoFormatStepL() CheckDisk res: %d"),r);
+#endif
+        }
+        else
+        {
+        //-- We do not need to perform full mount in this case, the TDrive object will be marked as changed in ~CFormatCB and the
+        //-- mount will be closed. Therefore on the first access to it it will be mounted normally.
+        FatMount().MountL(ETrue); //-- force mount
+        }
+
+    __PRINT1(_L("CFatFormatCB::DoFormatStepL() Format complete drv:%d"), DriveNumber());
+	}
+
+
+//-------------------------------------------------------------------------------------------------------------------
+
+/**
+    Initialize the user specific format parameters for fixed sized disk.
+    
+    @param  aDiskSizeInSectors disk size in sectors
+    @return system-wide error code
+*/
+TInt CFatFormatCB::InitFormatDataForFixedSizeDiskUser(TInt aDiskSizeInSectors)
+	{
+    __PRINT1(_L("CFatFormatCB::InitFormatDataForFixedSizeDiskUser() sectors:%d"), aDiskSizeInSectors);
+    Dump_TLDFormatInfo(iSpecialInfo());
+
+    //-- KErrArgument will be returned if iSpecialInfo().iFATBits isn't one of EFB32, EFB16, EFB32
+
+    if(iSpecialInfo().iFlags & TLDFormatInfo::EOneFatTable)
+		iNumberOfFats = 1;
+    else if(iSpecialInfo().iFlags & TLDFormatInfo::ETwoFatTables)
+		iNumberOfFats = 2;
+    else if(Drive().IsRemovable())
+		iNumberOfFats = KNumberOfFatsExternal;
+	else
+		iNumberOfFats = KNumberOfFatsInternal;
+
+
+    if(iSpecialInfo().iReservedSectors == 0)
+        iReservedSectors = KDefFatResvdSec; //-- user hasn't specified reserved sectors count, use default (FAT12/16)
+    else
+        iReservedSectors = iSpecialInfo().iReservedSectors;
+
+
+    const TInt KMaxSecPerCluster    = 64; 
+	const TInt KDefaultSecPerCluster= 8;   //-- default value, if the iSpecialInfo().iSectorsPerCluster isn't specified
+
+    iSectorsPerCluster = iSpecialInfo().iSectorsPerCluster;
+    if(iSectorsPerCluster <= 0)
+        {//-- default value, user hasn't specified TLDFormatInfo::iSectorsPerCluster
+        iSectorsPerCluster = KDefaultSecPerCluster; //-- will be adjusted later
+        }
+    else
+        {
+        iSectorsPerCluster = Min(1<<Log2(iSectorsPerCluster), KMaxSecPerCluster);
+	    }
+
+    //-----------------------------------------
+
+    if (aDiskSizeInSectors < 4096) // < 2MB
+        {
+        iSectorsPerCluster = 1;
+		iRootDirEntries = 128;
+        }
+	else if (aDiskSizeInSectors < 8192) // < 4MB
+        {
+        iSectorsPerCluster = Min(iSectorsPerCluster, 2);
+		iRootDirEntries = 256;
+        }
+	else if (aDiskSizeInSectors < 32768) // < 16MB
+        {
+        iSectorsPerCluster = Min(iSectorsPerCluster, 4);
+		iRootDirEntries = 512;
+        }
+	else if (aDiskSizeInSectors < 1048576) // < 512MB
+        {
+        iSectorsPerCluster = Min(iSectorsPerCluster, 8);
+		iRootDirEntries = 512;
+        }
+    else // FAT32
+		{
+        iRootDirEntries = 512;
+        iSectorsPerCluster = Min(iSectorsPerCluster, KMaxSecPerCluster);
+        }
+
+
+    //-----------------------------------------
+
+	TLDFormatInfo::TFATBits fatBits = iSpecialInfo().iFATBits;
+	if (fatBits == TLDFormatInfo::EFBDontCare)
+		{
+        const TFatType fatType = SuggestFatType();
+		switch(fatType)
+			{
+			case EFat12:
+				fatBits = TLDFormatInfo::EFB12;
+				break;
+			case EFat16:
+				fatBits = TLDFormatInfo::EFB16;
+				break;
+			case EFat32:
+				fatBits = TLDFormatInfo::EFB32;
+				break;
+			case EInvalid:
+				ASSERT(0);
+			}
+		}
+
+    TFatType reqFatType(EInvalid); //-- requested FAT type
+
+    switch (fatBits)
+		{
+		case TLDFormatInfo::EFB12:
+			iFileSystemName=KFileSystemName12;
+			iSectorsPerFat=MaxFat12Sectors();
+			reqFatType = EFat12;
+            break;
+
+		case TLDFormatInfo::EFB16:
+			iFileSystemName=KFileSystemName16;
+			iSectorsPerFat=MaxFat16Sectors();
+			reqFatType = EFat16;
+            break;
+
+		case TLDFormatInfo::EFB32:
+			iFileSystemName=KFileSystemName32;
+			iSectorsPerFat=MaxFat32Sectors();
+	        
+			iRootDirEntries = 0;
+			iRootClusterNum = 2;
+			
+            if(iSpecialInfo().iReservedSectors == 0)
+                iReservedSectors = KDefFat32ResvdSec; //-- user hasn't specified reserved sectors count, use default (FAT32)
+            else
+                iReservedSectors = iSpecialInfo().iReservedSectors;
+
+			reqFatType = EFat32;
+            break;
+
+        default:
+            __PRINT(_L("CFatFormatCB::InitFormatDataForFixedSizeDiskUser() Incorrect FAT type specifier!"));
+            return KErrArgument;
+		}
+	
+        //-- check if we can format the volume with requested FAT type
+        const TFatType fatType = SuggestFatType();
+        if(fatType != reqFatType)
+			{
+			//-- volume metrics don't correspond to the requested FAT type
+            __PRINT(_L("CFatFormatCB::InitFormatDataForFixedSizeDiskUser() FAT type mismatch!"));
+            return KErrArgument;
+			}
+
+        return KErrNone;
+    }
+
+/**
+    Initialize the format parameters for a custom fixed sized disk
+
+    @param  aFormatInfo The custom format parameters
+    @return system-wide error code
+*/
+TInt CFatFormatCB::InitFormatDataForFixedSizeDiskCustom(const TLDFormatInfo& aFormatInfo)
+	{
+    __PRINT(_L("CFatFormatCB::InitFormatDataForFixedSizeDiskCustom()"));
+    Dump_TLDFormatInfo(aFormatInfo);
+
+	if(aFormatInfo.iFlags & TLDFormatInfo::EOneFatTable)
+		iNumberOfFats = 1;
+    else if(aFormatInfo.iFlags & TLDFormatInfo::ETwoFatTables)
+		iNumberOfFats = 2;
+    else if(Drive().IsRemovable())
+		iNumberOfFats = KNumberOfFatsExternal;
+	else
+		iNumberOfFats = KNumberOfFatsInternal;	
+
+	iRootDirEntries=512;
+
+	iSectorsPerCluster = aFormatInfo.iSectorsPerCluster;
+	iSectorsPerTrack   = aFormatInfo.iSectorsPerTrack;
+	iNumberOfHeads	   = aFormatInfo.iNumberOfSides;
+	iReservedSectors   = aFormatInfo.iReservedSectors ? aFormatInfo.iReservedSectors : KDefFatResvdSec;
+	
+    switch (aFormatInfo.iFATBits)
+		{
+		case TLDFormatInfo::EFB12:
+			iFileSystemName = KFileSystemName12;
+			iSectorsPerFat  = MaxFat12Sectors();
+			break;
+
+		case TLDFormatInfo::EFB16:
+			iFileSystemName = KFileSystemName16;
+			iSectorsPerFat  = MaxFat16Sectors();
+            break;
+
+		case TLDFormatInfo::EFB32:
+			iFileSystemName  = KFileSystemName32;
+			iReservedSectors = aFormatInfo.iReservedSectors ? aFormatInfo.iReservedSectors : KDefFat32ResvdSec;
+			iSectorsPerFat   = MaxFat32Sectors();
+			iRootDirEntries  = 0;
+			iRootClusterNum  = 2;
+            break;
+
+		default:
+			{
+			TInt64 clusters64 = (aFormatInfo.iCapacity / KDefaultSectorSize) / iSectorsPerCluster;
+			TInt clusters = I64LOW(clusters64);
+			if (clusters < 4085)
+				{
+				iFileSystemName = KFileSystemName12;
+				iSectorsPerFat  = MaxFat12Sectors();
+				}
+			else if(clusters < 65525)
+				{
+				iFileSystemName = KFileSystemName16;
+				iSectorsPerFat  = MaxFat16Sectors();
+                }
+			else
+				{
+				iFileSystemName  = KFileSystemName32;
+				iReservedSectors = aFormatInfo.iReservedSectors ? aFormatInfo.iReservedSectors : KDefFat32ResvdSec;
+				iSectorsPerFat   = MaxFat32Sectors();
+				iRootDirEntries  = 0;
+				iRootClusterNum  = 2;
+				}
+			}
+		}
+
+    return KErrNone;
+	}
+
+void CFatFormatCB::RecordOldInfoL()
+    {
+    // Check if mount or disk is corrupt
+    // This should be stored in member variable because FatMount is remounted
+    //  every time RFormat::Next() gets called thus FatMount().Initialised()
+    //  will be inconsistent with previous state.
+	TLocalDriveCapsV3Buf caps;
+	User::LeaveIfError(LocalDrive()->Caps(caps));
+	iVariableSize=((caps().iMediaAtt)&KMediaAttVariableSize) ? (TBool)ETrue : (TBool)EFalse;
+    iDiskCorrupt = !FatMount().ConsistentState();
+    iBadClusters.Reset();
+    iBadSectors.Reset();
+    if (!iVariableSize && !iDiskCorrupt && (iMode&EQuickFormat))
+        {
+        iOldFirstFreeSector = FatMount().iFirstFreeByte>>FatMount().SectorSizeLog2();
+        iOldSectorsPerCluster = FatMount().SectorsPerCluster();
+
+        FatMount().FAT().InvalidateCacheL(); //-- invalidate whole FAT cache
+
+        // Collect bad cluster information from current FAT table
+        const TInt maxClusterNum = FatMount().UsableClusters() + KFatFirstSearchCluster;
+        const TUint32 mark = FatMount().Is32BitFat() ? KBad_32Bit : (FatMount().Is16BitFat() ? KBad_16Bit : KBad_12Bit);
+        
+        for (TInt i=KFatFirstSearchCluster; i<maxClusterNum; ++i)
+            {
+            if (FatMount().FAT().ReadL(i) == mark)
+                iBadClusters.AppendL(i);
+            }
+        }
+    }
+
+
+
+
+TInt CFatFormatCB::BadSectorToCluster()
+    {
+    TInt sizeofFatAndRootDir;
+    if (iFileSystemName != KFileSystemName32)
+		sizeofFatAndRootDir = iSectorsPerFat*iNumberOfFats + ((iRootDirEntries*KSizeOfFatDirEntry+(1<<iSectorSizeLog2)-1)>>iSectorSizeLog2);
+    else
+        sizeofFatAndRootDir = (iRootClusterNum-2) * iSectorsPerCluster;
+    TInt firstFreeSector = iReservedSectors + sizeofFatAndRootDir;
+
+    // Check in rare case that corrupt in critical area
+    // which includes bootsector, FAT table, (and root dir if not FAT32)
+    TInt i, r;
+    for (i=0; i<iBadSectors.Count(); ++i)
+        {
+        TInt badSector = iBadSectors[i];
+        // Check in rare case that corrupt in critical area
+        // which includes bootsector, FAT table, (and root dir if not FAT32)
+        if (firstFreeSector > badSector)
+            {
+            if (badSector == 0) // Boot sector corrupt
+                return KErrCorrupt;
+            if (iFileSystemName==KFileSystemName32 && badSector==1) // FSInfo corrupt
+                return KErrCorrupt;
+            if (badSector < iReservedSectors) // Harmless in reserved area
+                continue;
+            // Extend reserved area to cover bad sector
+            iReservedSectors = badSector + 1;
+            firstFreeSector = iReservedSectors + sizeofFatAndRootDir;
+            continue;
+            }
+
+        // Figure out bad cluster number and record it
+        TUint cluster = (badSector-firstFreeSector)/iSectorsPerCluster+2;
+        if (iBadClusters.Find(cluster) == KErrNotFound)
+            {
+            if ((r=iBadClusters.Append(cluster)) != KErrNone)
+                return r;
+            if (iFileSystemName==KFileSystemName32 && iRootClusterNum==cluster)
+                iRootClusterNum++;
+            }
+        }
+    return KErrNone;
+    }
+
+/**
+Create the File system information sector and its backup copy on a disk. 
+Note that CFatMountCB is still not in mounted state, so we can not rely on it.
+
+@leave System wide error codes
+*/
+void CFatFormatCB::CreateFSInfoSectorL()
+	{
+	__PRINT1(_L("CFatFormatCB::CreateFSInfoSectorL() drv:%d"), DriveNumber());
+	
+    ASSERT(Is32BitFat()); //-- Actually, CFatMount shall be in a consistent state.
+
+    TFSInfo fsInfo;
+	TBuf8<KSizeOfFSInfo> fsInfoSecBuf;
+    
+    const TUint32 freeSectors  = iMaxDiskSectors - (iReservedSectors + (iNumberOfFats * iSectorsPerFat));
+    const TUint32 freeClusters = (freeSectors / iSectorsPerCluster) - 1; //-- 1st cluster is taken by empty Root Dir on FAT32
+    const TUint32 nextFreeClust = iRootClusterNum+1; 
+
+    fsInfo.SetFreeClusterCount(freeClusters);
+    fsInfo.SetNextFreeCluster(nextFreeClust);
+
+    fsInfo.Externalize(fsInfoSecBuf); //-- put data to the sector buffer
+
+    User::LeaveIfError(LocalDrive()->Write(KFSInfoSectorNum*iBytesPerSector, fsInfoSecBuf)); //-- main FSInfo Sector
+    User::LeaveIfError(LocalDrive()->Write(KBkFSInfoSectorNum*iBytesPerSector, fsInfoSecBuf)); //-- Backup FSInfo Sector
+
+	}
+
+/**
+Create the reserved boot sector and its backup copy on a disk. 
+These are located at sectors 2 & 8
+
+@leave System wide error codes
+*/
+void CFatFormatCB::CreateReservedBootSectorL()
+	{
+	__PRINT1(_L("CFatFormatCB::CreateReserveBootSectorL() drv:%d"), DriveNumber());
+	
+    ASSERT(Is32BitFat());
+
+    TFatBootSector bootSector;
+
+	User::LeaveIfError(FatMount().DoWriteBootSector(KReservedBootSectorNum*KDefaultSectorSize, bootSector));
+	User::LeaveIfError(FatMount().DoWriteBootSector(KBkReservedBootSectorNum*KDefaultSectorSize, bootSector));    
+	}
+
+
+
+