/**
Read non aligned boot data from media into TFatBootSector structure
@param aMediaPos media position the data will be read from
@param aBootSector refrence to TFatBootSector populate
@return Media read error code
*/
TInt CFatMountCB::DoReadBootSector(TInt64 aMediaPos, TFatBootSector& aBootSector) const
{
__PRINT2(_L("#- CFatMountCB::DoReadBootSector() drv:%d, pos:0x%x"),Drive().DriveNumber(), (TUint32)aMediaPos);
ASSERT(aMediaPos>=0);
TBuf8<KSizeOfFatBootSector> bootSecBuf(KSizeOfFatBootSector);
//-- read boot sector from the media
TInt r=LocalDrive()->Read(aMediaPos, KSizeOfFatBootSector, bootSecBuf);
if (r != KErrNone)
{
__PRINT2(_L("CFatMountCB::DoReadBootSector() failed! drv:%d, code:%d"),Drive().DriveNumber(),r);
//-- fiddling with the error code; taken from MountL()
if (r==KErrNotSupported)
return KErrNotReady;
#if defined(_LOCKABLE_MEDIA)
else if(r==KErrLocked)
return KErrLocked;
#endif
else if (r!=KErrNoMemory && r!=KErrNotReady && r!=KErrCorrupt && r!=KErrUnknown)
return KErrCorrupt;
return r;
}
ASSERT(r==KErrNone);
//-- initialise TFatBootSector object
aBootSector.Internalize(bootSecBuf);
//-- Validate the partition size, and fix up if the out of bounds
TLocalDriveCapsV2Buf localDriveCaps;
r = LocalDrive()->Caps(localDriveCaps);
if (r != KErrNone)
{
//-- fiddling with the error code; taken from MountL()
if (r!=KErrNoMemory && r!=KErrNotReady && r!=KErrCorrupt && r!=KErrUnknown)
return KErrCorrupt;
else
return r;
}
if(!(localDriveCaps().iMediaAtt & KMediaAttVariableSize))
{//-- this is not a RAM drive.
const TUint32 maxSectors = I64LOW(localDriveCaps().iSize >> KDefSectorSzLog2);
if(aBootSector.TotalSectors())
aBootSector.SetTotalSectors(Min(aBootSector.TotalSectors(), maxSectors));
else
aBootSector.SetHugeSectors(Min(aBootSector.HugeSectors(), maxSectors));
}
return KErrNone;
}
/**
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());
_LIT8(KName_Fat12,"FAT12 "); ///< Name in BPB given to a Fat12 volume
_LIT8(KName_Fat16,"FAT16 "); ///< Name in BPB given to a Fat16 volume
_LIT8(KName_Fat32,"FAT32 "); ///< Name in BPB given to a Fat32 volume
_LIT8(KDefaultVendorID, "EPOC"); ///< Vendor Name for BPB for any volume formated using a Symbian OS device
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();
bootSector.SetUniqueID(I64LOW(timeID.Int64())); // Generate Volume UniqueID from time
bootSector.SetVolumeLabel(_L8(""));
//-- set a text string in BPB that corresponds to the FS type
switch(FatType())
{
case EFat12:
bootSector.SetFileSysType(KName_Fat12);
break;
case EFat16:
bootSector.SetFileSysType(KName_Fat16);
break;
case EFat32:
bootSector.SetFileSysType(KName_Fat32);
break;
default:
ASSERT(0);
User::Leave(KErrArgument);
};
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<=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));
}
}
