func()

in server/service.go [386:438]

• 46 lines of code
• 8 McCabe index (conditional complexity)

func (svr *Service) HandleListener(l net.Listener) {
	// Listen for incoming connections from client.
	for {
		c, err := l.Accept()
		if err != nil {
			log.Warn("Listener for incoming connections from client closed")
			return
		}
		// inject xlog object into net.Conn context
		xl := xlog.New()
		ctx := context.Background()

		c = frpNet.NewContextConn(xlog.NewContext(ctx, xl), c)

		log.Trace("start check TLS connection...")
		originConn := c
		var isTLS, custom bool
		c, isTLS, custom, err = frpNet.CheckAndEnableTLSServerConnWithTimeout(c, svr.tlsConfig, svr.cfg.TLSOnly, connReadTimeout)
		if err != nil {
			log.Warn("CheckAndEnableTLSServerConnWithTimeout error: %v", err)
			originConn.Close()
			continue
		}
		log.Trace("check TLS connection success, isTLS: %v custom: %v", isTLS, custom)

		// Start a new goroutine to handle connection.
		go func(ctx context.Context, frpConn net.Conn) {
			if svr.cfg.TCPMux {
				fmuxCfg := fmux.DefaultConfig()
				fmuxCfg.KeepAliveInterval = time.Duration(svr.cfg.TCPMuxKeepaliveInterval) * time.Second
				fmuxCfg.LogOutput = io.Discard
				session, err := fmux.Server(frpConn, fmuxCfg)
				if err != nil {
					log.Warn("Failed to create mux connection: %v", err)
					frpConn.Close()
					return
				}

				for {
					stream, err := session.AcceptStream()
					if err != nil {
						log.Debug("Accept new mux stream error: %v", err)
						session.Close()
						return
					}
					go svr.handleConnection(ctx, stream)
				}
			} else {
				svr.handleConnection(ctx, frpConn)
			}
		}(ctx, c)
	}
}