Do not allow to call (*restart.Context).Start() more than one time

pkg/restart/restart.go

@@ -12,8 +12,8 @@ import (
 )
 
 var (
-	// ErrAlreadyStarting is returned on starting attempt when starting is in progress.
-	ErrAlreadyStarting = errors.New("already starting")
+	// ErrAlreadyStarted is returned when Start is already called.
+	ErrAlreadyStarted = errors.New("already started")
 )
 
 const (
@@ -28,7 +28,7 @@ type Context struct {
 	log         logrus.FieldLogger
 	cmd         *exec.Cmd
 	checkDelay  time.Duration
-	isStarting  int32
+	isStarted   int32
 	appendDelay bool // disabled in tests
 }
 
@@ -66,12 +66,10 @@ func (c *Context) SetCheckDelay(delay time.Duration) {
 
 // Start starts a new executable using Context.
 func (c *Context) Start() error {
-	if !atomic.CompareAndSwapInt32(&c.isStarting, 0, 1) {
-		return ErrAlreadyStarting
+	if !atomic.CompareAndSwapInt32(&c.isStarted, 0, 1) {
+		return ErrAlreadyStarted
 	}
 
-	defer atomic.StoreInt32(&c.isStarting, 0)
-
 	errCh := c.startExec()
 
 	ticker := time.NewTicker(c.checkDelay)

pkg/restart/restart_test.go

@@ -33,10 +33,10 @@ func TestContext_RegisterLogger(t *testing.T) {
 }
 
 func TestContext_Start(t *testing.T) {
-	cc := CaptureContext()
-	assert.NotZero(t, len(cc.cmd.Args))
-
 	t.Run("executable started", func(t *testing.T) {
+		cc := CaptureContext()
+		assert.NotZero(t, len(cc.cmd.Args))
+
 		cmd := "touch"
 		path := "/tmp/test_start"
 		cc.cmd = exec.Command(cmd, path) // nolint:gosec
@@ -47,6 +47,9 @@ func TestContext_Start(t *testing.T) {
 	})
 
 	t.Run("bad args", func(t *testing.T) {
+		cc := CaptureContext()
+		assert.NotZero(t, len(cc.cmd.Args))
+
 		cmd := "bad_command"
 		cc.cmd = exec.Command(cmd) // nolint:gosec
 
@@ -60,6 +63,9 @@ func TestContext_Start(t *testing.T) {
 	})
 
 	t.Run("already starting", func(t *testing.T) {
+		cc := CaptureContext()
+		assert.NotZero(t, len(cc.cmd.Args))
+
 		cmd := "touch"
 		path := "/tmp/test_start"
 		cc.cmd = exec.Command(cmd, path) // nolint:gosec
@@ -74,7 +80,7 @@ func TestContext_Start(t *testing.T) {
 		err2 := <-errCh
 		errors := []error{err1, err2}
 
-		assert.Contains(t, errors, ErrAlreadyStarting)
+		assert.Contains(t, errors, ErrAlreadyStarted)
 		assert.Contains(t, errors, nil)
 
 		assert.NoError(t, os.Remove(path))