Function postMessageToThread

lib/internal/worker/messaging.js:191–234

(threadId, value, transferList, timeout)

}

async function postMessageToThread(threadId, value, transferList, timeout) {
  if (typeof transferList === 'number' && typeof timeout === 'undefined') {
    timeout = transferList;
    transferList = [];
  }

  if (typeof timeout !== 'undefined') {
    validateNumber(timeout, 'timeout', 0);
  }

  if (threadId === currentThreadId) {
    throw new ERR_WORKER_MESSAGING_SAME_THREAD();
  }

  const memory = constructSharedArrayBuffer(WORKER_MESSAGING_SHARED_DATA);
  const status = new Int32Array(memory);
  const promise = AtomicsWaitAsync(status, WORKER_MESSAGING_STATUS_INDEX, 0, timeout).value;

  const message = {
    type: messageTypes.SEND_MESSAGE_TO_WORKER,
    source: currentThreadId,
    destination: threadId,
    value,
    memory,
    transferList,
  };

  if (isMainThread) {
    handleMessageFromThread(message);
  } else {
    mainThreadPort.postMessage(message, transferList);
  }

  // Wait for the response
  const response = await promise;

  if (response === 'timed-out') {
    throw new ERR_WORKER_MESSAGING_TIMEOUT();
  } else if (status[WORKER_MESSAGING_RESULT_INDEX] === WORKER_MESSAGING_RESULT_NO_LISTENERS) {
    throw new ERR_WORKER_MESSAGING_FAILED();
  } else if (status[WORKER_MESSAGING_RESULT_INDEX] === WORKER_MESSAGING_RESULT_LISTENER_ERROR) {
    throw new ERR_WORKER_MESSAGING_ERRORED();
  }
}

module.exports = {
  createMainThreadPort,