class CFPropertyList::Binary

def load(opts)
  @unique_table = {}
  @count_objects = 0
  @object_refs = 0
  @written_object_count = 0
  @object_table = []
  @object_ref_size = 0
  @offsets = []
  fd = nil
  if(opts.has_key?(:file))
    fd = File.open(opts[:file],"rb")
    file = opts[:file]
  else
    fd = StringIO.new(opts[:data],"rb")
    file = "<string>"
  end
  # first, we read the trailer: 32 byte from the end
  fd.seek(-32,IO::SEEK_END)
  buff = fd.read(32)
  offset_size, object_ref_size, number_of_objects, top_object, table_offset = buff.unpack "x6CCx4Nx4Nx4N"
  # after that, get the offset table
  fd.seek(table_offset, IO::SEEK_SET)
  coded_offset_table = fd.read(number_of_objects * offset_size)
  raise CFFormatError.new("#{file}: Format error!") unless coded_offset_table.bytesize == number_of_objects * offset_size
  @count_objects = number_of_objects
  # decode offset table
  if(offset_size != 3)
    formats = ["","C*","n*","","N*"]
    @offsets = coded_offset_table.unpack(formats[offset_size])
  else
    @offsets = coded_offset_table.unpack("C*").each_slice(3).map {
      |x,y,z| (x << 16) | (y << 8) | z
    }
  end
  @object_ref_size = object_ref_size
  val = read_binary_object_at(file,fd,top_object)
  fd.close
  val
end