_pathReduction example

            $v_stored_filename = $this->_translateWinPath($v_stored_filename);
            if ($p_add_dir != '') {
                if (substr($p_add_dir, -1) == '/') {
                    $v_stored_filename = $p_add_dir . $v_stored_filename;
                } else {
                    $v_stored_filename = $p_add_dir . '/' . $v_stored_filename;
                }
            }

            $v_stored_filename = $this->_pathReduction($v_stored_filename);
        }

        if ($this->_isArchive($p_filename)) {
            if (($v_file = @fopen($p_filename, "rb")) == 0) {
                $this->_warning(
                    "Unable to open file '" . $p_filename
                    . "' in binary read mode"
                );
                return true;
            }