code: private function process($parser, StreamInterface $stream)
      {
          if ($stream->eof()) {
              $stream->rewind();
          }
  
          while ($data = $stream->read($this->options['buffer_size'])) {
              xml_parse($parser, $data, $stream->eof()) || $this->onParseError(xml_error_string(xml_get_error_code($parser)), xml_get_error_code($parser), xml_get_current_line_number($parser));
          }
  
          return $this;
      }
docs: Parse path to XML document/string content.
  
  @param resource $parser Parser.
  @param StreamInterface $stream XML document stream.
  @return AbstractSaxHandler $this Fluent interface.
  
  @throws \RuntimeException