docs: public static Optional<Long> readMaybeVLong(ByteBuf bf) {
        if (bf.readableBytes() >= 1) {
           byte b = bf.readByte();
  
           return read(bf, b, 7, (long) b & 0x7F, 1);
        } else {
           bf.resetReaderIndex();
           return Optional.empty();
        }
     }