Function readWriteHelper

src/js/streams.ts:168–197

(stream: Stream, cb: () => number, method: string)

}

function readWriteHelper(stream: Stream, cb: () => number, method: string) {
  let nbytes;
  try {
    nbytes = handleEAGAIN(cb);
  } catch (e: any) {
    if (e && e.code && Module.ERRNO_CODES[e.code]) {
      throw new FS.ErrnoError(Module.ERRNO_CODES[e.code]);
    }
    if (isErrnoError(e)) {
      // the handler set an errno, propagate it
      throw e;
    }
    console.error(`Error thrown in ${method}:`);
    console.error(e);
    throw new FS.ErrnoError(cDefs.EIO);
  }
  if (nbytes === undefined) {
    // Prevent an infinite loop caused by incorrect code that doesn't return a
    // value
    // Maybe we should set nbytes = buffer.length here instead?
    console.warn(
      `${method} returned undefined; a correct implementation must return a number`,
    );
    throw new FS.ErrnoError(cDefs.EIO);
  }
  if (nbytes !== 0) {
    stream.node.timestamp = Date.now();
  }
  return nbytes;
}

const prepareBuffer = (
  buffer: Uint8Array,