tools.go_stun

Yohn Y. 2021-02-25 Parent:102fbdab34d8

tools.go_stun/main.go

* Делаем вывод удобоваримым для windows . Мелкий рефакторинг

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@1	14 LOG_IDENT string = "net-a0fs-gostun"
awgur@0	15 )
awgur@0	16
awgur@3	17 const (
awgur@3	18 LOGP_INFO = iota
awgur@3	19 LOGP_WARN
awgur@3	20 LOGP_ERR
awgur@3	21 )
awgur@3	22
awgur@3	23 type logMessage struct {
awgur@3	24 prio uint
awgur@3	25 msg string
awgur@3	26 }
awgur@3	27
awgur@3	28 var log_chan = make(chan logMessage, 100)
awgur@3	29
awgur@3	30 func log_handler() {
awgur@3	31 var err error
awgur@3	32
awgur@3	33 log, err := syslog.New(syslog.LOG_USER, LOG_IDENT)
awgur@3	34 if err != nil {
awgur@3	35 panic(err)
awgur@3	36 }
awgur@3	37
awgur@3	38 for log_msg := range log_chan {
awgur@3	39 switch log_msg.prio {
awgur@3	40 case LOGP_INFO:
awgur@3	41 err = log.Info(log_msg.msg)
awgur@3	42 case LOGP_WARN:
awgur@3	43 err = log.Warning(log_msg.msg)
awgur@3	44 case LOGP_ERR:
awgur@3	45 err = log.Err(log_msg.msg)
awgur@3	46 default:
awgur@3	47 err = log.Err(fmt.Sprintf("Unknown type of log priority: %v", log_msg.prio))
awgur@3	48 }
awgur@3	49
awgur@3	50 if err != nil {
awgur@3	51 panic(err)
awgur@3	52 }
awgur@3	53 }
awgur@3	54 }
awgur@3	55
awgur@3	56 func log_info(msg string, vars ...interface{}) {
awgur@3	57 log_chan <- logMessage{
awgur@3	58 prio: LOGP_INFO,
awgur@3	59 msg: fmt.Sprintf(msg, vars...)}
awgur@3	60 }
awgur@3	61
awgur@3	62 func log_warn(msg string, vars ...interface{}) {
awgur@3	63 log_chan <- logMessage{
awgur@3	64 prio: LOGP_WARN,
awgur@3	65 msg: fmt.Sprintf(msg, vars...)}
awgur@3	66 }
awgur@3	67
awgur@3	68 func log_err(msg string, vars ...interface{}) {
awgur@3	69 log_chan <- logMessage{
awgur@3	70 prio: LOGP_ERR,
awgur@3	71 msg: fmt.Sprintf(msg, vars...)}
awgur@3	72 }
awgur@3	73
awgur@0	74 func getPort() (res string, err error) {
awgur@0	75 if len(os.Args) < 2 {
awgur@0	76 err = errors.New("No port specify")
awgur@0	77 } else {
awgur@0	78 res = fmt.Sprintf(":%s", os.Args[1])
awgur@0	79 }
awgur@0	80 return
awgur@0	81 }
awgur@0	82
awgur@0	83 func fail(code int, msg string) {
awgur@0	84 usage := "Usage: cmd port"
awgur@0	85 usage += "\n port: port number for listening clients"
awgur@0	86
awgur@0	87 fmt.Fprintln(os.Stderr, msg)
awgur@0	88 fmt.Fprintln(os.Stderr, usage)
awgur@0	89 os.Exit(code)
awgur@0	90 return
awgur@0	91 }
awgur@0	92
awgur@0	93 func handler(conn net.Conn) {
awgur@0	94 _s_tm := time.Now()
awgur@0	95 remoteAddr := conn.RemoteAddr().String()
awgur@4	96 res := ""
awgur@0	97
awgur@0	98 defer func() {
awgur@0	99 var err error
awgur@0	100 _s_tmd := time.Now().Sub(_s_tm)
awgur@0	101 if r_err := recover(); r_err != nil {
awgur@3	102 log_err("Error on service for %s (service time: %v): %v", remoteAddr, _s_tmd, r_err)
awgur@0	103 } else {
awgur@0	104 err = conn.Close()
awgur@0	105 if err != nil {
awgur@3	106 log_err("Error on closing socket when service %s (service time: %v): %v",
awgur@3	107 remoteAddr, _s_tmd, err)
awgur@0	108
awgur@0	109 } else {
awgur@3	110 log_info("Ok service %s in %v", remoteAddr, _s_tmd)
awgur@0	111 }
awgur@0	112 }
awgur@0	113 }()
awgur@0	114
awgur@0	115 addr_spit := strings.Split(remoteAddr, ":")
awgur@0	116 addr_last := len(addr_spit) - 1
awgur@2	117 addr := strings.Join(addr_spit[:addr_last], ":")
awgur@2	118
awgur@2	119 dns_names, err := net.LookupAddr(strings.Trim(addr, "[] "))
awgur@2	120 if err != nil {
awgur@3	121 log_warn("Fail to resolve dns name for %s: %v", remoteAddr, err)
awgur@2	122 } else {
awgur@2	123 for _, dns_name := range dns_names {
awgur@4	124 res += fmt.Sprintf("Name: %s\r\n", dns_name)
awgur@2	125 }
awgur@2	126 }
awgur@4	127 res += fmt.Sprintf("IP: %s\r\n", addr)
awgur@4	128 res += fmt.Sprintf("Port: %s\r\n", addr_spit[addr_last])
awgur@4	129 res += "\n"
awgur@0	130
awgur@4	131 if _, err := conn.Write([]byte(res)); err != nil {
awgur@1	132 panic(err.Error())
awgur@0	133 }
awgur@0	134 }
awgur@0	135
awgur@0	136 func main() {
awgur@0	137 port, err := getPort()
awgur@0	138 if err != nil {
awgur@0	139 fail(1, fmt.Sprint("Error in parsing port number: ", err))
awgur@0	140 }
awgur@0	141
awgur@3	142 go log_handler()
awgur@3	143
awgur@0	144 svc, err := net.Listen("tcp", port)
awgur@0	145 if err != nil {
awgur@0	146 fail(2, fmt.Sprint("Fail to open socket: ", err))
awgur@0	147 }
awgur@0	148
awgur@0	149 for {
awgur@0	150 conn, err := svc.Accept()
awgur@0	151 if err != nil {
awgur@0	152 fail(1, fmt.Sprint("Error accepting connections: ", err))
awgur@0	153 }
awgur@0	154 go handler(conn)
awgur@0	155 }
awgur@0	156 }