Function createZstdHandle

lib/internal/streams/iter/transform.js:250–296

* Create a bare Zstd handle. * @returns {{ handle: object, writeState: Uint32Array, chunkSize: number }}

(mode, options, processCallback, onError)

 * @returns {{ handle: object, writeState: Uint32Array, chunkSize: number }}
 */
function createZstdHandle(mode, options, processCallback, onError) {
  const isCompress = mode === ZSTD_COMPRESS;

  // Validate before creating native handle.
  const chunkSize = validateChunkSize(options);
  const dictionary = validateDictionary(options.dictionary);
  const maxParam = isCompress ? kMaxZstdCParam : kMaxZstdDParam;
  validateParams(options.params, maxParam, ERR_ZSTD_INVALID_PARAM);

  const pledgedSrcSize = options.pledgedSrcSize;
  if (pledgedSrcSize !== undefined) {
    if (typeof pledgedSrcSize !== 'number' || NumberIsNaN(pledgedSrcSize)) {
      throw new ERR_INVALID_ARG_TYPE('options.pledgedSrcSize', 'number',
                                     pledgedSrcSize);
    }
    if (pledgedSrcSize < 0) {
      throw new ERR_OUT_OF_RANGE('options.pledgedSrcSize', '>= 0',
                                 pledgedSrcSize);
    }
  }

  const handle = isCompress ?
    new binding.ZstdCompress() : new binding.ZstdDecompress();
  const writeState = new Uint32Array(2);

  const initArray = isCompress ? zstdInitCParamsArray : zstdInitDParamsArray;
  TypedArrayPrototypeFill(initArray, -1);
  if (options.params) {
    const params = options.params;
    const keys = ObjectKeys(params);
    for (let i = 0; i < keys.length; i++) {
      const key = +keys[i];
      initArray[key] = params[keys[i]];
    }
  }

  handle.onerror = onError;
  handle.init(
    initArray,
    pledgedSrcSize,
    writeState,
    processCallback,
    dictionary,
  );

  return { __proto__: null, handle, writeState, chunkSize };
}

// ---------------------------------------------------------------------------
// Core: makeZlibTransform