n, err := r.r.Read(p)
	if n > 0 && r.off+int64(n) > r.start && r.off < r.end {
		cstart := r.start - r.off
		if cstart < 0 {
			cstart = 0
		}
		cend := r.end - r.off
		if cend > int64(n) {
			cend = int64(n)
		}
		zeros := make([]byte, cend-cstart)
		copy(p[cstart:cend], zeros)
	}
	r.off += int64(n)
	return n, err
}