zlib.brotliCompressSync results in no response

[zyscoder]

• Version: v16.0.0-pre
• Platform: Linux 5.8.0-38-generic The binary and long term compatibility with node #43~20.04.1-Ubuntu SMP Tue Jan 12 16:39:47 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
• Subsystem: zlib.brotliCompressSync

What steps will reproduce the bug?

Setup a node instance,

» node

and run the following javascript code.

zlib = require('zlib');zlib.brotliCompressSync('',{flush:3,finishFlush:4});

Then the node instance stuck and has no response even with "Ctl-D".

How often does it reproduce? Is there a required condition?

This can be always triggered following the steps above.

What is the expected behavior?

Don't cause any no response.

What do you see instead?

» node
Welcome to Node.js v16.0.0-pre.
Type ".help" for more information.
> zlib = require('zlib');zlib.brotliCompressSync('',{flush:3,finishFlush:4});


^C^C^C^C

                                                                                                                                                                                                 

Additional information

[XadillaX]

It seems brotli does not has BrotliEncoderOperation with 4:

/** Operations that can be performed by streaming encoder. */
typedef enum BrotliEncoderOperation {
  /**
   * Process input.
   *
   * Encoder may postpone producing output, until it has processed enough input.
   */
  BROTLI_OPERATION_PROCESS = 0,
  /**
   * Produce output for all processed input.
   *
   * Actual flush is performed when input stream is depleted and there is enough
   * space in output stream. This means that client should repeat
   * ::BROTLI_OPERATION_FLUSH operation until @p available_in becomes @c 0, and
   * ::BrotliEncoderHasMoreOutput returns ::BROTLI_FALSE. If output is acquired
   * via ::BrotliEncoderTakeOutput, then operation should be repeated after
   * output buffer is drained.
   *
   * @warning Until flush is complete, client @b SHOULD @b NOT swap,
   *          reduce or extend input stream.
   *
   * When flush is complete, output data will be sufficient for decoder to
   * reproduce all the given input.
   */
  BROTLI_OPERATION_FLUSH = 1,
  /**
   * Finalize the stream.
   *
   * Actual finalization is performed when input stream is depleted and there is
   * enough space in output stream. This means that client should repeat
   * ::BROTLI_OPERATION_FINISH operation until @p available_in becomes @c 0, and
   * ::BrotliEncoderHasMoreOutput returns ::BROTLI_FALSE. If output is acquired
   * via ::BrotliEncoderTakeOutput, then operation should be repeated after
   * output buffer is drained.
   *
   * @warning Until finalization is complete, client @b SHOULD @b NOT swap,
   *          reduce or extend input stream.
   *
   * Helper function ::BrotliEncoderIsFinished checks if stream is finalized and
   * output fully dumped.
   *
   * Adding more input data to finalized stream is impossible.
   */
  BROTLI_OPERATION_FINISH = 2,
  /**
   * Emit metadata block to stream.
   *
   * Metadata is opaque to Brotli: neither encoder, nor decoder processes this
   * data or relies on it. It may be used to pass some extra information from
   * encoder client to decoder client without interfering with main data stream.
   *
   * @note Encoder may emit empty metadata blocks internally, to pad encoded
   *       stream to byte boundary.
   *
   * @warning Until emitting metadata is complete client @b SHOULD @b NOT swap,
   *          reduce or extend input stream.
   *
   * @warning The whole content of input buffer is considered to be the content
   *          of metadata block. Do @b NOT @e append metadata to input stream,
   *          before it is depleted with other operations.
   *
   * Stream is soft-flushed before metadata block is emitted. Metadata block
   * @b MUST be no longer than than 16MiB.
   */
  BROTLI_OPERATION_EMIT_METADATA = 3
} BrotliEncoderOperation;