Method Read

ws.go:209–369

(p []byte)

}

func (r *websocketReader) Read(p []byte) (int, error) {
	var err error
	var buf []byte

	if l := len(r.ib); l > 0 {
		buf = r.ib
		r.ib = nil
	} else {
		if len(r.pending) > 0 {
			return r.drainPending(p), nil
		}

		// If we have a deferred close error (from a previous Read that
		// had both data frames and a close frame), return it now that
		// pending data has been drained.
		if r.closeErr != nil {
			err := r.closeErr
			r.closeErr = nil
			return 0, err
		}

		// Get some data from the underlying reader.
		n, err := r.r.Read(p)
		if err != nil {
			return 0, err
		}
		buf = p[:n]
	}

	// Now parse this and decode frames. We will possibly read more to
	// ensure that we get a full frame.
	var (
		tmpBuf []byte
		pos    int
		max    = len(buf)
		rem    = 0
	)
	for pos < max {
		b0 := buf[pos]
		frameType := wsOpCode(b0 & 0xF)
		final := b0&wsFinalBit != 0
		compressed := b0&wsRsv1Bit != 0
		pos++

		tmpBuf, pos, err = wsGet(r.r, buf, pos, 1)
		if err != nil {
			return 0, err
		}
		b1 := tmpBuf[0]

		// Store size in case it is < 125
		rem = int(b1 & 0x7F)

		switch frameType {
		case wsPingMessage, wsPongMessage, wsCloseMessage:
			if rem > wsMaxControlPayloadSize {
				return 0, fmt.Errorf(
					"control frame length bigger than maximum allowed of %v bytes",