h          hash.Hash
	shardSize  int64
	hashBytes  []byte
}

func (b *streamingBitrotReader) Close() error {
	if b.rc == nil {
		return nil
	}
	if closer, ok := b.rc.(io.Closer); ok {
		// drain the body for connection reuse at network layer.
		xhttp.DrainBody(struct {
			io.Reader
			io.Closer
		}{
			Reader: b.rc,
			Closer: closeWrapper(func() error { return nil }),
		})
		return closer.Close()