fix tunnel close bug & add a cli example

example/cli/go.mod

@@ -0,0 +1,8 @@
+module cli
+
+go 1.12
+
+// require github.com/piaodazhu/proxylite v0.0.0-20230813091435-b2c8f474a9fc
+replace github.com/piaodazhu/proxylite => ../../
+
+require github.com/piaodazhu/proxylite v0.0.0-00010101000000-000000000000

example/cli/main.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"flag"
+
+	"github.com/piaodazhu/proxylite"
+)
+
+func main() {
+	var name string
+	flag.StringVar(&name, "n", "abc", "service name")
+	flag.Parse()
+	cli := proxylite.NewProxyLiteClient(":9933")
+	port, ok := cli.AnyPort()
+	if !ok {
+		panic("anyport() error")
+	}
+	_, done, err := cli.RegisterInnerService(proxylite.RegisterInfo{
+		OuterPort: port,
+		InnerAddr: ":123",
+		Name: name,
+		Message: "hello world",
+	}, proxylite.ControlInfo{})
+	if err != nil {
+		panic(err)
+	}
+	<-done
+}

example/server/main.go

@@ -3,6 +3,6 @@ import "github.com/piaodazhu/proxylite"
 
 func main() {
 	server := proxylite.NewProxyLiteServer()
-	server.AddPort(9930, 9932)
+	server.AddPort(9940, 9948)
 	panic(server.Run(":9933"))
 }

server.go

@@ -279,6 +279,7 @@ func (s *ProxyLiteServer) startTunnel(tn *tunnel) {
 	listener, err := net.Listen("tcp", fmt.Sprintf("0.0.0.0:%d", tn.service.Port))
 	if err != nil {
 		(*tn.innerConn).Close()
+		tn.empty = true
 		return
 	}