docs: function sanitize(str, len) {
      len = len || 256;
      if (!str || typeof str === 'string' && str.length < 1)
          return str;
      if (typeof str !== 'string' || str.length > len)
          return null;
      return str.replace(/[\0\x08\x09\x1a\n\r"'\\\%]/g, function (char) {
          switch (char) {
              case "\0":
                  return "\\0";
              case "\x08":
                  return "\\b";
              case "\x09":
                  return "\\t";
              case "\x1a":
                  return "\\z";
              case "\n":
                  return "\\n";
              case "\r":
                  return "\\r";
              case "\"":
              case "'":
              case "\\":
              case "%":
                  return "\\" + char; // prepends a backslash to backslash, percent,
              // and double/single quotes
          }
      });
  }