Function WriteHeader

write.go:49–87

WriteHeader writes header binary representation into w.

(w io.Writer, h Header)

// WriteHeader writes header binary representation into w.
func WriteHeader(w io.Writer, h Header) error {
	// Make slice of bytes with capacity 14 that could hold any header.
	bts := make([]byte, MaxHeaderSize)

	if h.Fin {
		bts[0] |= bit0
	}
	bts[0] |= h.Rsv << 4
	bts[0] |= byte(h.OpCode)

	var n int
	switch {
	case h.Length <= len7:
		bts[1] = byte(h.Length)
		n = 2

	case h.Length <= len16:
		bts[1] = 126
		binary.BigEndian.PutUint16(bts[2:4], uint16(h.Length))
		n = 4

	case h.Length <= len64:
		bts[1] = 127
		binary.BigEndian.PutUint64(bts[2:10], uint64(h.Length))
		n = 10

	default:
		return ErrHeaderLengthUnexpected
	}

	if h.Masked {
		bts[1] |= bit0
		n += copy(bts[n:], h.Mask[:])
	}

	_, err := w.Write(bts[:n])

	return err
}

// WriteFrame writes frame binary representation into w.
func WriteFrame(w io.Writer, f Frame) error {