var wroteBuf bytes.Buffer
	readHash := crc32.NewIEEE()
	wroteHash := crc32.NewIEEE()
	read := io.Writer(readHash)
	wrote := io.Writer(wroteHash)
	if debug {
		read = io.MultiWriter(read, &readBuf)
		wrote = io.MultiWriter(wrote, &wroteBuf)
	}
	debugln := func(args ...interface{}) {
		if debug {
			fmt.Println(args...)
		}
	}
	// Inject random reader/writer sleeps.