cr.excess = max(cr.excess, 0)
	if cr.excess > 16*1024 {
		cr.err = errors.New("chunked encoding contains too much non-data")
	}
	if cr.n == 0 {
		cr.err = io.EOF
	}
}

func (cr *chunkedReader) chunkHeaderAvailable() bool {
	n := cr.r.Buffered()
	if n > 0 {
		peek, _ := cr.r.Peek(n)
		return bytes.IndexByte(peek, '\n') >= 0
	}
	return false
}

func (cr *chunkedReader) Read(b []uint8) (n int, err error) {