Fix restart command when ctrld service was already stopped

cmd/ctrld/cli.go

@@ -550,13 +550,10 @@ func initCLI() {
 				return
 			}
 			initLogging()
-			tasks := []task{{s.Restart, true}}
-			// On Windows, s.Restart will return error unless service is running.
-			if runtime.GOOS == "windows" {
-				tasks = []task{
-					{s.Start, false},
-					{s.Restart, true},
-				}
+
+			tasks := []task{
+				{s.Stop, false},
+				{s.Start, true},
 			}
 			if doTasks(tasks) {
 				dir, err := userHomeDir()

cmd/ctrld/service.go

@@ -63,6 +63,16 @@ func (s *sysV) Stop() error {
 	return err
 }
 
+func (s *sysV) Restart() error {
+	if !s.installed() {
+		return service.ErrNotInstalled
+	}
+	// We don't care about error returned by s.Stop,
+	// because the service may already be stopped.
+	_ = s.Stop()
+	return s.Start()
+}
+
 func (s *sysV) Status() (service.Status, error) {
 	if !s.installed() {
 		return service.StatusUnknown, service.ErrNotInstalled