if algo == HighwayHash256S {
		return newStreamingBitrotReader(disk, data, bucket, filePath, tillOffset, algo, shardSize)
	}
	return newWholeBitrotReader(disk, bucket, filePath, algo, tillOffset, sum)
}

// Close all the readers.
func closeBitrotReaders(rs []io.ReaderAt) {
	for _, r := range rs {
		if r != nil {

		return 0, io.EOF
	}
	r.prevRune = -1
	n = copy(b, r.s[r.i:])
	r.i += int64(n)
	return
}

// ReadAt implements the [io.ReaderAt] interface.
func (r *Reader) ReadAt(b []byte, off int64) (n int, err error) {
	// cannot modify state - see io.ReaderAt
	if off < 0 {
		return 0, errors.New("bytes.Reader.ReadAt: negative offset")
	}
	if off >= int64(len(r.s)) {
		return 0, io.EOF
	}

	var sz int64
	f, e := os.Open(downloadPath)
	if e != nil {
		return e
	}
	if st, e := f.Stat(); e == nil {
		sz = st.Size()
	}
	defer f.Close()
	r = f

	zr, e := zip.NewReader(r.(io.ReaderAt), sz)
	if e != nil {
		return e
	}
	for _, file := range zr.File {
		if !file.FileInfo().IsDir() && strings.HasSuffix(file.Name, "xl.meta") {
			r, e := file.Open()
			if e != nil {
				return e
			}

type parallelReader struct {
	readers       []io.ReaderAt
	orgReaders    []io.ReaderAt
	dataBlocks    int
	offset        int64
	shardSize     int64
	shardFileSize int64
	buf           [][]byte
	readerToBuf   []int
	stashBuffer   []byte
}

// newParallelReader returns parallelReader.
func newParallelReader(readers []io.ReaderAt, e Erasure, offset, totalLength int64) *parallelReader {

		closeBitrotWriters(writers)
		if err != nil {
			t.Fatalf("Test %d: failed to create random test data: %v", i, err)
		}

		readers := make([]io.ReaderAt, len(disks))
		for i, disk := range disks {
			shardFilesize := erasure.ShardFileSize(test.size)