private bool ProbeSectorSize(int size)
{
if (_data.Length < 257 * (long)size)
{
return(false);
}
_data.Position = 256 * (long)size;
DescriptorTag dt;
if (!DescriptorTag.TryFromStream(_data, out dt))
{
return(false);
}
return(dt.TagIdentifier == TagIdentifier.AnchorVolumeDescriptorPointer &&
dt.TagLocation == 256);
}
private void Initialize()
{
Context = new UdfContext()
{
PhysicalPartitions = new Dictionary <ushort, PhysicalPartition>(),
PhysicalSectorSize = (int)_sectorSize,
LogicalPartitions = new List <LogicalPartition>(),
};
IBuffer dataBuffer = new StreamBuffer(_data, Ownership.None);
AnchorVolumeDescriptorPointer avdp = AnchorVolumeDescriptorPointer.FromStream(_data, 256, _sectorSize);
uint sector = avdp.MainDescriptorSequence.Location;
bool terminatorFound = false;
while (!terminatorFound)
{
_data.Position = sector * (long)_sectorSize;
DescriptorTag dt;
if (!DescriptorTag.TryFromStream(_data, out dt))
{
break;
}
switch (dt.TagIdentifier)
{
case TagIdentifier.PrimaryVolumeDescriptor:
_pvd = PrimaryVolumeDescriptor.FromStream(_data, sector, _sectorSize);
break;
case TagIdentifier.ImplementationUseVolumeDescriptor:
// Not used
break;
case TagIdentifier.PartitionDescriptor:
PartitionDescriptor pd = PartitionDescriptor.FromStream(_data, sector, _sectorSize);
if (Context.PhysicalPartitions.ContainsKey(pd.PartitionNumber))
{
throw new IOException("Duplicate partition number reading UDF Partition Descriptor");
}
Context.PhysicalPartitions[pd.PartitionNumber] = new PhysicalPartition(pd, dataBuffer, _sectorSize);
break;
case TagIdentifier.LogicalVolumeDescriptor:
_lvd = LogicalVolumeDescriptor.FromStream(_data, sector, _sectorSize);
break;
case TagIdentifier.UnallocatedSpaceDescriptor:
// Not used for reading
break;
case TagIdentifier.TerminatingDescriptor:
terminatorFound = true;
break;
default:
break;
}
sector++;
}
// Convert logical partition descriptors into actual partition objects
for (int i = 0; i < _lvd.PartitionMaps.Length; ++i)
{
Context.LogicalPartitions.Add(LogicalPartition.FromDescriptor(Context, _lvd, i));
}
byte[] fsdBuffer = UdfUtilities.ReadExtent(Context, _lvd.FileSetDescriptorLocation);
if (DescriptorTag.IsValid(fsdBuffer, 0))
{
FileSetDescriptor fsd = Utilities.ToStruct <FileSetDescriptor>(fsdBuffer, 0);
RootDirectory = (Directory)File.FromDescriptor(Context, fsd.RootDirectoryIcb);
}
}