private void processZeroByte(final Long input, final Consumer<Long> writer) {
    // If input == 0, encode 0 value as 0x80
    if (input == 0) {
      writeRaw(Bytes.of(0x80));
    } else {
      writer.accept(input);
    }
  }
Check if the incoming value is 0 and writes it as 0x80, per the spec.

@param input The value to check
@param writer The consumer to write the non-zero output
ethereum/rlp/src/main/java/org/hyperledger/besu/ethereum/rlp/RLPOutput.java