    # File lib/rack/handler/webrick.rb, line 58
          def service(req, res)
            res.rack = true
            env = req.meta_vars
            env.delete_if { |k, v| v.nil? }

            rack_input = StringIO.new(req.body.to_s)
            rack_input.set_encoding(Encoding::BINARY) if rack_input.respond_to?(:set_encoding)

            env.update({"rack.version" => Rack::VERSION,
                         "rack.input" => rack_input,
                         "rack.errors" => $stderr,

                         "rack.multithread" => true,
                         "rack.multiprocess" => false,
                         "rack.run_once" => false,

                         "rack.url_scheme" => ["yes", "on", "1"].include?(env["HTTPS"]) ? "https" : "http",

                         "rack.hijack?" => true,
                         "rack.hijack" => lambda { raise NotImplementedError, "only partial hijack is supported."},
                         "rack.hijack_io" => nil,
                       })

            env["HTTP_VERSION"] ||= env["SERVER_PROTOCOL"]
            env[QUERY_STRING] ||= ""
            unless env[PATH_INFO] == ""
              path, n = req.request_uri.path, env["SCRIPT_NAME"].length
              env[PATH_INFO] = path[n, path.length-n]
            end
            env["REQUEST_PATH"] ||= [env["SCRIPT_NAME"], env[PATH_INFO]].join

            status, headers, body = @app.call(env)
            begin
              res.status = status.to_i
              headers.each { |k, vs|
                next if k.downcase == "rack.hijack"

                if k.downcase == "set-cookie"
                  res.cookies.concat vs.split("\n")
                else
                  # Since WEBrick won't accept repeated headers,
                  # merge the values per RFC 1945 section 4.2.
                  res[k] = vs.split("\n").join(", ")
                end
              }

              io_lambda = headers["rack.hijack"]
              if io_lambda
                rd, wr = IO.pipe
                res.body = rd
                res.chunked = true
                io_lambda.call wr
              elsif body.respond_to?(:to_path)
                res.body = ::File.open(body.to_path, 'rb')
              else
                body.each { |part|
                  res.body << part
                }
              end
            ensure
              body.close  if body.respond_to? :close
            end
          end