# File lib/fog/aws/storage.rb, line 679
          def next_chunk
            data = body.read(0x10000)
            if data.nil?
              self.finished = true
              data = ''
            end
            self.signature = sign_chunk(data, signature)
            "#{data.length.to_s(16)};chunk-signature=#{signature}\r\n#{data}\r\n"
          end