Moved restore code out of create and made to be called after create.

Docker expects containers to be created before they are restored.
However, gVisor restoring requires specificactions regarding the kernel
and the file system. These actions were originally in booting the sandbox.

Now setting up the file system is deferred until a call to a call to
runsc start. In the restore case, the kernel is destroyed and a new kernel
is created in the same process, as we need the same process for Docker.

These changes required careful execution of concurrent processes which
required the use of a channel.

Full docker integration still needs the ability to restore into the same
container.

PiperOrigin-RevId: 205161441
Change-Id: Ie1d2304ead7e06855319d5dc310678f701bd099f

1 files changed, 5 insertions, 6 deletions

diff --git a/runsc/cmd/restore.go b/runsc/cmd/restore.go
index 69cdb35c1..6dc044672 100644
--- a/runsc/cmd/restore.go
+++ b/runsc/cmd/restore.go
@@ -94,16 +94,15 @@ func (r *Restore) Execute(_ context.Context, f *flag.FlagSet, args ...interface{
 
 	restoreFile := filepath.Join(r.imagePath, checkpointFileName)
 
-	cont, err := container.Create(id, spec, conf, bundleDir, r.consoleSocket, r.pidFile, restoreFile)
+	c, err := container.Load(conf.RootDir, id)
 	if err != nil {
-		Fatalf("error restoring container: %v", err)
+		Fatalf("error loading container: %v", err)
 	}
-
-	if err := cont.Start(conf); err != nil {
-		Fatalf("error starting container: %v", err)
+	if err := c.Restore(spec, conf, restoreFile); err != nil {
+		Fatalf("error restoring container: %v", err)
 	}
 
-	ws, err := cont.Wait()
+	ws, err := c.Wait()
 	if err != nil {
 		Fatalf("error running container: %v", err)
 	}