# File lib/rack/file.rb, line 24
    def _call(env)
      if env["PATH_INFO"].include? ".."
        body = "Forbidden\n"
        size = body.respond_to?(:bytesize) ? body.bytesize : body.size
        return [403, {"Content-Type" => "text/plain","Content-Length" => size.to_s}, [body]]
      end

      @path = F.join(@root, Utils.unescape(env["PATH_INFO"]))
      ext = F.extname(@path)[1..-1]

      if F.file?(@path) && F.readable?(@path)
        [200, {
           "Last-Modified"  => F.mtime(@path).httpdate,
           "Content-Type"   => MIME_TYPES[ext] || "text/plain",
           "Content-Length" => F.size(@path).to_s
         }, self]
      else
        body = "File not found: #{env["PATH_INFO"]}\n"
        size = body.respond_to?(:bytesize) ? body.bytesize : body.size
        [404, {"Content-Type" => "text/plain", "Content-Length" => size.to_s}, [body]]
      end
    end