--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/userlibandfileserver/fileserver/sfat/sl_check.cpp	Thu Dec 17 09:24:54 2009 +0200
@@ -0,0 +1,307 @@
+// Copyright (c) 1998-2009 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_check.cpp
+// 
+//
+
+//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+//!!
+//!! WARNING!! DO NOT edit this file !! '\sfat' component is obsolete and is not being used. '\sfat32'replaces it
+//!!
+//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+#include "sl_std.h"
+#include "sl_scandrv.h"
+
+const TInt KMaxBufferSize=8192;
+
+
+TBool CCheckFatTable::IsEof16Bit(TInt aCluster) const
+{
+    return(aCluster>=0xFFF8 && aCluster<=0xFFFF);
+}
+
+TBool CCheckFatTable::IsEof12Bit(TInt aCluster) const
+{
+    return(aCluster>=0xFF8 && aCluster<=0xFFF);
+}
+
+TInt CCheckFatTable::MaxFatIndex() const
+    {   
+    __ASSERT_DEBUG((TUint)iMaxFatIndex>=KFatFirstSearchCluster, Fault(ECheckFatIndexZero));
+    return(iMaxFatIndex);
+    }
+
+
+CCheckFatTable* CCheckFatTable::NewL(CFatMountCB* aOwner)
+//
+// Create a CCheckFatTable
+//
+    {
+    CCheckFatTable* fatTable;
+    fatTable=new(ELeave) CCheckFatTable(aOwner);
+    return(fatTable);
+    }
+
+
+CCheckFatTable::CCheckFatTable(CFatMountCB* aOwner)
+//
+// Constructor
+//
+    {
+    iOwner=aOwner;
+    }
+
+CCheckFatTable::~CCheckFatTable()
+//
+// Destructor
+//
+    {
+    User::Free(iCheckFat);
+    }
+
+
+void CCheckFatTable::InitializeL()
+//
+// Initialize the check fat table
+//
+    {
+    __PRINT(_L("CCheckFatTable::InitializeL"));
+
+    TInt fatSize=iOwner->FatSizeInBytes();
+
+    if(iCheckFat==NULL)
+        iCheckFat=(TUint8*)User::AllocL(fatSize);
+    else
+        iCheckFat=(TUint8*)User::ReAllocL(iCheckFat,fatSize);
+    Mem::FillZ(iCheckFat,fatSize);
+    iMaxFatIndex=iOwner->UsableClusters()+1;
+    if(iOwner->Is16BitFat())
+        {
+        __ASSERT_ALWAYS(iMaxFatIndex>0 && iMaxFatIndex<EOF_16Bit && !IsEof16Bit(iMaxFatIndex),User::Leave(KErrCorrupt));
+        }
+    else
+        {
+        __ASSERT_ALWAYS(iMaxFatIndex>0 && iMaxFatIndex<EOF_12Bit && !IsEof12Bit(iMaxFatIndex),User::Leave(KErrCorrupt));
+        }
+    WriteMediaDescriptor();
+    
+    __PRINT2(_L("fatSize=%d,iCheckFat=0x%x"),fatSize,iCheckFat);
+    }
+
+
+/**
+@return ETrue if found errors in FAT 
+*/
+TBool CCheckFatTable::FlushL()
+//
+// Flush iCheckFat to the media, comparing each sector to corresponding 
+// sector in all fats (cf.CFixedCache::FlushL)
+//  
+    {
+    TBool bErrFound = EFalse;
+    
+    __PRINT(_L("CCheckFatTable::FlushL()"));
+    HBufC8* hBuf=HBufC8::New(KMaxBufferSize);
+    if (hBuf==NULL)
+        hBuf=HBufC8::NewL(KMaxBufferSize/4);
+    CleanupStack::PushL(hBuf);
+
+    TUint8* ptr=(TUint8*)hBuf->Ptr();
+    TInt maxSize=hBuf->Des().MaxSize();
+
+    TPtr8 fatBuffer(ptr,maxSize);
+    TInt fatSize=iOwner->FatSizeInBytes();
+    TInt remainder=fatSize;
+    TInt offset=iOwner->StartOfFatInBytes();
+    TUint8* dataPtr=iCheckFat;
+    TFatDriveInterface& drive = iOwner->DriveInterface();
+    TInt fatNumber=iOwner->NumberOfFats();
+    
+    while(remainder)
+        {
+        TInt s=Min(fatBuffer.MaxSize(),remainder);
+        TInt fatCount=fatNumber;
+        TInt fatPos=0;
+        while(fatCount)
+            {
+            TInt fatOffset=offset+fatPos;
+            User::LeaveIfError(drive.ReadCritical(fatOffset,s,fatBuffer));
+            TInt rem2=s;
+            TInt offset2=fatOffset;
+            TUint8* dataPtr2=dataPtr;
+            TInt bufOffset=0;
+            while(rem2)
+                {
+                TInt s2=Min(rem2,512);
+                TInt r=Mem::Compare(dataPtr2,s2,fatBuffer.Ptr()+bufOffset,s2);
+                if (r!=0)
+                    {
+                    bErrFound = ETrue;
+                    TPtrC8 dataBuf(dataPtr2,s2);
+                    User::LeaveIfError(drive.WriteCritical(offset2,dataBuf));
+                    }
+                rem2-=s2;
+                offset2+=s2;
+                dataPtr2+=s2;
+                bufOffset+=s2;
+                }
+            --fatCount;
+            fatPos+=fatSize;
+            }
+        offset+=s;
+        dataPtr+=s;
+        remainder-=s;
+        }
+
+    CleanupStack::PopAndDestroy();
+
+    return bErrFound;
+    }
+
+void CCheckFatTable::WriteMediaDescriptor()
+//
+// Write media descriptor to first byte and 0xFF to
+// remaining bytes of first two entries
+//
+    {
+    __PRINT(_L("CCheckFatTable::WriteMediaDescriptor"));
+    iCheckFat[0]=KBootSectorMediaDescriptor;
+    iCheckFat[1]=0xFF;
+    iCheckFat[2]=0xFF;
+    if (iOwner->Is16BitFat())
+        iCheckFat[3]=0xFF;
+    }
+
+TInt CCheckFatTable::PosInBytes(TInt aFatIndex) const
+//
+// Return number of bytes into the fat
+//
+    {
+    TInt fatPosInBytes;
+    if (iOwner->Is16BitFat())
+        fatPosInBytes=aFatIndex<<1;
+    else
+        // this is used since 8-bit access will be used for reading/writing
+        fatPosInBytes=(aFatIndex*3>>1);
+    return(fatPosInBytes);
+    }
+
+
+TInt CCheckFatTable::PosInIndex(TInt aBytePos) const
+//
+// Return index given byte position in fat
+//
+    {
+    if(iOwner->Is16BitFat())
+        return(aBytePos>>1);
+    else
+        return((aBytePos<<1)/3);
+    }
+
+
+TInt CCheckFatTable::ReadL(TInt aFatIndex) const
+//
+// Read a value from the check fat
+//
+    {
+    __ASSERT_ALWAYS((TUint32)aFatIndex >=KFatFirstSearchCluster && aFatIndex<=MaxFatIndex(),User::Leave(KErrCorrupt));
+    TUint clusterVal;
+    if(iOwner->Is16BitFat())
+        clusterVal=*(TUint16*)(iCheckFat+PosInBytes(aFatIndex));
+    else
+        {
+        TUint8* pCluster=iCheckFat+PosInBytes(aFatIndex);
+        clusterVal=pCluster[0]|(pCluster[1]<<8);
+        TBool oddCluster=(aFatIndex)&1;
+        if(oddCluster)
+            clusterVal>>=4;
+        clusterVal&=0xFFF;
+        }
+    return(clusterVal);
+    }
+
+
+void CCheckFatTable::WriteL(TInt aFatIndex,TInt aValue)
+//
+// Write a value to the check fat
+//
+    {
+    if(iOwner->Is16BitFat())
+        __ASSERT_ALWAYS((TUint32)aFatIndex>=KFatFirstSearchCluster && aFatIndex<=MaxFatIndex() && aValue>=0 && aValue<=0xFFFF,User::Leave(KErrCorrupt));
+    else
+        __ASSERT_ALWAYS((TUint32)aFatIndex>=KFatFirstSearchCluster && aFatIndex<=MaxFatIndex() && aValue>=0 && aValue<=0xFFF,User::Leave(KErrCorrupt));
+    TUint8* p=(TUint8*)(iCheckFat+PosInBytes(aFatIndex));
+    if (iOwner->Is16BitFat())
+        { 
+        *(TUint16*)p=(TUint16)aValue;
+        return;
+        }
+    TUint8 mask=0x0F;
+    TBool odd=(aFatIndex)&1;
+    TUint8 fatVal;
+    if(odd)
+        {
+        mask<<=4;
+        aValue<<=4;
+        fatVal=p[0];
+        fatVal&=~mask;
+        fatVal|=(TUint8)(aValue&0xFF);
+        p[0]=fatVal;
+        p[1]=(TUint8)(aValue>>8);
+        }
+    else
+        {
+        p[0]=(TUint8)(aValue&0xFF);
+        fatVal=p[1];
+        fatVal&=~mask;
+        fatVal|=(TUint8)(aValue>>8);
+        p[1]=fatVal;
+        }
+    return;
+    }
+    
+
+TBool CCheckFatTable::GetNextClusterL(TInt& aCluster) const
+//
+// Get the next cluster in the chain from the check fat.
+//
+    {
+    __PRINT(_L("CCheckFatTable::GetNextClusterL"));
+    TBool ret;
+    TInt nextCluster=ReadL(aCluster);
+    if (iOwner->Is16BitFat())
+        ret=!IsEof16Bit(nextCluster);
+    else
+        ret=!IsEof12Bit(nextCluster);
+    if (ret)
+        aCluster=nextCluster;
+    return(ret);
+    }
+
+void CCheckFatTable::WriteFatEntryEofFL(TInt aCluster)
+//
+// Write EOF to aCluster
+//
+    {
+    __PRINT(_L("CCheckFatTable::WriteFatEntryEofF"));
+    if (iOwner->Is16BitFat())
+        WriteL(aCluster,EOF_16Bit);
+    else
+        WriteL(aCluster,EOF_12Bit);
+    }
+
+