Method Write

proxy/udp.go:227–308

(b []byte)

}

func (c *udpBridgeConn) Write(b []byte) (n int, err error) {
	// For simplicity, when return "n", it should always equal to the total length of "b" if writing succeeded
	// No ErrShortWrite shall happen
	defer func() {
		if err == nil {
			n = len(b)
			c.logger.D("UDP", "Write bytes", n)
		} else {
			c.logger.D("UDP", "Write error", err)
		}
	}()

	if b == nil || len(b) == 0 {
		return
	}

	var ln int
	var buf []byte

	if c.incompleteLen {
		c.incompleteLen = false

		ln = int(binary.BigEndian.Uint16([]byte{c.waitingMore.buf[0], b[0]}))
		buf = b[1:]

		goto TEST
	}

	if c.waitingMore.remain > 0 {
		remain := c.waitingMore.remain
		c.waitingMore.remain -= len(b)

		if c.waitingMore.remain == 0 {
			// Best case
			return c.write(append(c.waitingMore.buf, b...))
		}

		if c.waitingMore.remain > 0 {
			// We still don't have enough data to write
			c.waitingMore.buf = append(c.waitingMore.buf, b...)
			return len(b), nil
		}

		// b contains more than what we need
		if n, err = c.write(append(c.waitingMore.buf, b[:remain]...)); err != nil {
			return
		}

		b = b[remain:]
		// Let's deal with the trailing bytes
	}

	if len(b) == 1 {
		c.logger.D("UDP", "Incomplete header")
		c.waitingMore.buf = b
		c.incompleteLen = true // "len" should have 2 bytes, we got 1
		return 1, nil
	}