fix: processing small timeouts

cmd/main.go

@@ -10,49 +10,14 @@ import (
 	flag "github.com/spf13/pflag"
 )
 
-func main() {
-	flag.IntVarP(&poolSize, "num_relays", "n", 100, `The number of concurrent relays tested.`)
-	flag.IntVarP(&goal, "working_relay_num_goal", "g", 5, `Test until at least this number of working relays are found`)
-	flag.StringVarP(&timeoutStr, "timeout", "t", "200ms", `Socket connection timeout`)
-	flag.StringVarP(&outfile, "outfile", "o", "", `Output reachable relays to file`)
-	flag.BoolVar(&torrc, "torrc", false, `Output reachable relays in torrc format (with "Bridge" prefix)`)
-	flag.StringArrayVarP(&urls, "url", "u", []string{}, `Preferred alternative URL for onionoo relay list. Could be used multiple times.`)
-	flag.StringArrayVarP(&port, "port", "p", []string{}, `Scan for relays running on specified port number. Could be used multiple times.`)
-	flag.BoolVarP(&ipv4, "ipv4", "4", false, `Use ipv4 only nodes`)
-	flag.BoolVarP(&ipv6, "ipv6", "6", false, `Use ipv6 only nodes`)
-	flag.BoolVarP(&jsonRelays, "json", "j", false, `Get available relays in json format`)
-	flag.BoolVarP(&silent, "silent", "s", false, `Silent mode`)
-	flag.StringVarP(&deadlineStr, "deadline", "d", "1m", `The deadline of program execution`)
-	flag.Usage = usage
-	flag.Parse()
-
-	timeout, err := time.ParseDuration(timeoutStr)
-	if err != nil {
-		color.Errorf("cannot parse timeout duration: %s\n", err)
-		os.Exit(1)
-	}
-
-	deadline, err := time.ParseDuration(deadlineStr)
-	if err != nil {
-		color.Errorf("cannot parse deadline duration: %s\n", err)
-		os.Exit(1)
-	}
+var torRc, jsonRelays, silent bool
+var outfile string
 
-	sc := scanner.New(
-		poolSize,
-		goal,
-		timeout,
-		outfile,
-		urls,
-		port,
-		ipv4,
-		ipv6,
-		silent,
-		deadline,
-	)
+func main() {
+	sc := create()
 
 	var prefix string
-	if torrc {
+	if torRc {
 		prefix = "Bridge "
 	}
 
@@ -87,7 +52,7 @@ func main() {
 	for _, el := range relays {
 		color.Fprintf(out, "%s%s %s\n", prefix, el.Address, el.Fingerprint)
 	}
-	if torrc {
+	if torRc {
 		color.Fprintf(out, "UseBridges 1\n")
 	}
 }
@@ -97,3 +62,61 @@ func usage() {
 	flag.PrintDefaults()
 	os.Exit(0)
 }
+
+func create() scanner.TorRelayScanner {
+	poolSize := flag.IntP("num_relays", "n", 100, `The number of concurrent relays tested.`)
+	goal := flag.IntP("working_relay_num_goal", "g", 5, `Test until at least this number of working relays are found`)
+	timeoutStr := flag.StringP("timeout", "t", "200ms", `Socket connection timeout`)
+	f := flag.StringP("outfile", "o", "", `Output reachable relays to file`)
+	t := flag.Bool("torrc", false, `Output reachable relays in torrc format (with "Bridge" prefix)`)
+	urls := flag.StringArrayP("url", "u", []string{}, `Preferred alternative URL for onionoo relay list. Could be used multiple times.`)
+	port := flag.StringArrayP("port", "p", []string{}, `Scan for relays running on specified port number. Could be used multiple times.`)
+	ipv4 := flag.BoolP("ipv4", "4", false, `Use ipv4 only nodes`)
+	ipv6 := flag.BoolP("ipv6", "6", false, `Use ipv6 only nodes`)
+	j := flag.BoolP("json", "j", false, `Get available relays in json format`)
+	s := flag.BoolP("silent", "s", false, `Silent mode`)
+	deadlineStr := flag.StringP("deadline", "d", "1m", `The deadline of program execution`)
+	flag.Usage = usage
+	flag.Parse()
+
+	outfile = *f
+	torRc = *t
+	jsonRelays = *j
+	silent = *s
+
+	timeout, err := time.ParseDuration(*timeoutStr)
+	if err != nil {
+		color.Printf("cannot parse timeout duration: %s\n", err)
+		os.Exit(1)
+	}
+
+	if timeout < 50*time.Millisecond {
+		color.Println("It doesn't make sense to set a timeout of less than 50 ms")
+		os.Exit(1)
+	}
+
+	deadline, err := time.ParseDuration(*deadlineStr)
+	if err != nil {
+		color.Printf("cannot parse deadline duration: %s\n", err)
+		os.Exit(1)
+	}
+
+	if timeout > deadline {
+		color.Println("The deadline must be greater than the timeout")
+		os.Exit(1)
+	}
+
+	sc := scanner.New(
+		*poolSize,
+		*goal,
+		timeout,
+		*urls,
+		*port,
+		*ipv4,
+		*ipv6,
+		silent,
+		deadline,
+	)
+
+	return sc
+}

models.go

@@ -18,8 +18,6 @@ type torRelayScanner struct {
 	goal int
 	// Socket connection timeout. default=1s
 	timeout time.Duration
-	// Output reachable relays to file. default=sys.stdout
-	outfile string
 	// Preferred alternative URL for onionoo relay list. Could be used multiple times
 	urls []string
 	// Scan for relays running on specified port number. Could be used multiple times

scanner.go

@@ -25,7 +25,6 @@ func New(
 	poolSize int,
 	goal int,
 	timeout time.Duration,
-	outfile string,
 	urlsList []string,
 	port []string,
 	ipv4 bool,
@@ -52,7 +51,6 @@ func New(
 		poolSize: poolSize,
 		goal:     goal,
 		timeout:  timeout,
-		outfile:  outfile,
 		urls:     urls,
 		ports:    port,
 		ipv4:     ipv4,
@@ -120,7 +118,6 @@ func (t *torRelayScanner) getRelays() Relays {
 			})
 		}
 		p.Wait()
-		close(chanRelays)
 	}()
 
 	bar := progressbar.NewOptions(
@@ -153,7 +150,8 @@ func (t *torRelayScanner) getRelays() Relays {
 			relays = append(relays, el)
 			_ = bar.Add(1)
 		case <-ctx.Done():
-			color.Fprintf(os.Stderr, "\nThe program was running for more than the specified time: %.0fm", t.deadline.Minutes())
+			_ = bar.Add(t.goal)
+			color.Fprintf(os.Stderr, "\nThe program was running for more than the specified time: %.2fm", t.deadline.Minutes())
 			os.Exit(1)
 		}
 	}
@@ -247,7 +245,8 @@ func (t *torRelayScanner) grab(addr string) (RelayInfo, error) {
 
 // tcpSocketConnectChecker just checked network connection with specific host:port
 func tcpSocketConnectChecker(addr string, timeout time.Duration) bool {
-	_, err := net.DialTimeout("tcp", addr, timeout)
+	d := net.Dialer{Deadline: time.Now().Add(timeout)}
+	_, err := d.Dial("tcp", addr)
 
 	return err == nil
 }