Merge pull request #3173 from giuseppe/use-wait-for-file

libpod: prefer WaitForFile to polling

libpod/container_internal.go

@@ -25,7 +25,6 @@ import (
 	opentracing "github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
-	kwait "k8s.io/apimachinery/pkg/util/wait"
 )
 
 const (
@@ -146,20 +145,10 @@ func (c *Container) exitFilePath() string {
 func (c *Container) waitForExitFileAndSync() error {
 	exitFile := c.exitFilePath()
 
-	err := kwait.ExponentialBackoff(
-		kwait.Backoff{
-			Duration: 500 * time.Millisecond,
-			Factor:   1.2,
-			Steps:    6,
-		},
-		func() (bool, error) {
-			_, err := os.Stat(exitFile)
-			if err != nil {
-				// wait longer
-				return false, nil
-			}
-			return true, nil
-		})
+	chWait := make(chan error)
+	defer close(chWait)
+
+	_, err := WaitForFile(exitFile, chWait, time.Second*5)
 	if err != nil {
 		// Exit file did not appear
 		// Reset our state

libpod/oci.go

@@ -17,7 +17,6 @@ import (
 	"github.com/opencontainers/selinux/go-selinux/label"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
-	kwait "k8s.io/apimachinery/pkg/util/wait"
 
 	// TODO import these functions into libpod and remove the import
 	// Trying to keep libpod from depending on CRI-O code
@@ -261,21 +260,13 @@ func (r *OCIRuntime) updateContainerStatus(ctr *Container, useRuntime bool) erro
 	// If we were, it should already be in the database
 	if ctr.state.State == ContainerStateStopped && oldState != ContainerStateStopped {
 		var fi os.FileInfo
-		err = kwait.ExponentialBackoff(
-			kwait.Backoff{
-				Duration: 500 * time.Millisecond,
-				Factor:   1.2,
-				Steps:    6,
-			},
-			func() (bool, error) {
-				var err error
+		chWait := make(chan error)
+		defer close(chWait)
+
+		_, err := WaitForFile(exitFile, chWait, time.Second*5)
+		if err == nil {
 			fi, err = os.Stat(exitFile)
-				if err != nil {
-					// wait longer
-					return false, nil
 		}
-				return true, nil
-			})
 		if err != nil {
 			ctr.state.ExitCode = -1
 			ctr.state.FinishedTime = time.Now()