tools.go_stun

Yohn Y. 2020-04-05 Child:4b125c1ef311

0:bfbb685d7758 Go to Latest

tools.go_stun/main.go

.. init

History
awgur@0 1 package main
awgur@0 2
awgur@0 3 import (
awgur@0 4 "errors"
awgur@0 5 "fmt"
awgur@0 6 "log/syslog"
awgur@0 7 "net"
awgur@0 8 "os"
awgur@0 9 "strings"
awgur@0 10 "time"
awgur@0 11 )
awgur@0 12
awgur@0 13 const (
awgur@0 14 LOG_IDENT string = "net.a0fs.gostun"
awgur@0 15 )
awgur@0 16
awgur@0 17 func getPort() (res string, err error) {
awgur@0 18 if len(os.Args) < 2 {
awgur@0 19 err = errors.New("No port specify")
awgur@0 20 } else {
awgur@0 21 res = fmt.Sprintf(":%s", os.Args[1])
awgur@0 22 }
awgur@0 23 return
awgur@0 24 }
awgur@0 25
awgur@0 26 func fail(code int, msg string) {
awgur@0 27 usage := "Usage: cmd port"
awgur@0 28 usage += "\n port: port number for listening clients"
awgur@0 29
awgur@0 30 fmt.Fprintln(os.Stderr, msg)
awgur@0 31 fmt.Fprintln(os.Stderr, usage)
awgur@0 32 os.Exit(code)
awgur@0 33 return
awgur@0 34 }
awgur@0 35
awgur@0 36 func handler(conn net.Conn) {
awgur@0 37 log, err := syslog.New(syslog.LOG_USER, LOG_IDENT)
awgur@0 38 if err != nil {
awgur@0 39 panic(err)
awgur@0 40 }
awgur@0 41
awgur@0 42 _s_tm := time.Now()
awgur@0 43 remoteAddr := conn.RemoteAddr().String()
awgur@0 44
awgur@0 45 defer func() {
awgur@0 46 var err error
awgur@0 47 _s_tmd := time.Now().Sub(_s_tm)
awgur@0 48 if r_err := recover(); r_err != nil {
awgur@0 49 err = log.Err(fmt.Sprintf("Error on service for %s (service time: %v): %v", remoteAddr, _s_tmd, r_err))
awgur@0 50 if err != nil {
awgur@0 51 panic(err)
awgur@0 52 }
awgur@0 53 } else {
awgur@0 54 err = conn.Close()
awgur@0 55 if err != nil {
awgur@0 56 err = log.Err(fmt.Sprintf("Error on closing socket when service %s (service time: %v): %v",
awgur@0 57 remoteAddr, _s_tmd, err))
awgur@0 58
awgur@0 59 if err != nil {
awgur@0 60 panic(err)
awgur@0 61 }
awgur@0 62 } else {
awgur@0 63 err = log.Info(fmt.Sprintf("Ok service %s in %v", remoteAddr, _s_tmd))
awgur@0 64 if err != nil {
awgur@0 65 panic(err)
awgur@0 66 }
awgur@0 67 }
awgur@0 68 }
awgur@0 69
awgur@0 70 }()
awgur@0 71
awgur@0 72 addr_spit := strings.Split(remoteAddr, ":")
awgur@0 73 addr_last := len(addr_spit) - 1
awgur@0 74 addr := "IP: " + strings.Join(addr_spit[:addr_last], ":") + "\n"
awgur@0 75 port := "Port: " + addr_spit[addr_last] + "\n"
awgur@0 76
awgur@0 77 if _, err := conn.Write([]byte(addr)); err != nil {
awgur@0 78 panic(err)
awgur@0 79 }
awgur@0 80 if _, err := conn.Write([]byte(port)); err != nil {
awgur@0 81 panic(err)
awgur@0 82 }
awgur@0 83 }
awgur@0 84
awgur@0 85 func main() {
awgur@0 86 port, err := getPort()
awgur@0 87 if err != nil {
awgur@0 88 fail(1, fmt.Sprint("Error in parsing port number: ", err))
awgur@0 89 }
awgur@0 90
awgur@0 91 svc, err := net.Listen("tcp", port)
awgur@0 92 if err != nil {
awgur@0 93 fail(2, fmt.Sprint("Fail to open socket: ", err))
awgur@0 94 }
awgur@0 95
awgur@0 96 for {
awgur@0 97 conn, err := svc.Accept()
awgur@0 98 if err != nil {
awgur@0 99 fail(1, fmt.Sprint("Error accepting connections: ", err))
awgur@0 100 }
awgur@0 101 go handler(conn)
awgur@0 102 }
awgur@0 103 }