/// <summary>
/// Parses the tag information from the buffer.
/// </summary>
/// <param name="start">The start index of the tag information.</param>
/// <param name="buffer">The buffer containing the data.</param>
/// <param name="size">The number of bytes to read.</param>
/// <returns>Returns true if the data was parsed sucessfully.</returns>
public bool Parse(int start, byte[] buffer, int size)
{
if (buffer == null)
{
throw new ArgumentNullException("buffer");
}
if (size < 16 || (start + size) > buffer.Length || buffer[start + 5] != 0)
{
return(false);
}
int sum = 0;
for (int i = 0; i < 16; i++)
{
if (i != 4)
{
sum = sum + buffer[start + i];
}
}
int m = (sum % 256);
if (m != buffer[start + 4])
{
return(false);
}
this.Identifier = UdfHelper.Get16(start, buffer);
return(true);
}
/// <summary>
/// Reads a logical volume descriptor from the buffer.
/// </summary>
/// <param name="buffer">The buffer to read the data from.</param>
/// <returns>Returns true if the descriptor is valid.</returns>
private bool ReadLogicalDescriptor(byte[] buffer)
{
LogicalVolume volume = new LogicalVolume();
volume.Id.Parse(84, buffer);
volume.BlockSize = UdfHelper.Get32(212, buffer);
if (volume.BlockSize < VirtualSectorSize || volume.BlockSize > MaxExtents)
{
return(false);
}
volume.FileSetLocation.Parse(248, buffer);
int numPartitionMaps = UdfHelper.Get32(268, buffer);
if (numPartitionMaps > MaxPartitions)
{
return(false);
}
int position = 440;
for (int index = 0; index < numPartitionMaps; index++)
{
if (position + 2 > SectorSize)
{
return(false);
}
PartitionMap pm = new PartitionMap();
pm.Type = buffer[position];
byte length = buffer[position + 1];
if (position + length > SectorSize)
{
return(false);
}
if (pm.Type == 1)
{
if (position + 6 > SectorSize)
{
return(false);
}
pm.PartitionNumber = UdfHelper.Get16(position + 4, buffer);
}
else
{
return(false);
}
position += length;
pm.PartitionIndex = volume.PartitionMaps.Count;
volume.PartitionMaps.Add(pm);
}
this.LogicalVolumes.Add(volume);
return(true);
}
/// <summary>
/// Reads a partition descriptor from the buffer.
/// </summary>
/// <param name="buffer">The buffer to read the partition data from.</param>
private void ReadPartitionDescriptor(byte[] buffer)
{
var partition = new Partition
{
Number = UdfHelper.Get16(22, buffer),
Position = UdfHelper.Get32(188, buffer),
Length = UdfHelper.Get32(192, buffer)
};
this.Partitions.Add(partition);
}
public void Parse(int start, byte[] buffer)
{
try {
this.FileType = (IcbFileType)buffer[start + 11];
} catch (InvalidCastException) {
this.FileType = IcbFileType.Other;
}
int flags = UdfHelper.Get16(start + 18, buffer);
try {
this.DescriptorType = (IcbDescriptorType)(flags & 3);
} catch (InvalidCastException) {
throw new InvalidOperationException();
}
}