Allow to checkpoint and restore a container with console

runc already supports this case, so we just need to run it with proper
options.

Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

cmd/ctr/commands/tasks/tasks_unix.go

@@ -69,7 +69,13 @@ func HandleConsoleResize(ctx gocontext.Context, task resizer, con console.Consol
 // NewTask creates a new task
 func NewTask(ctx gocontext.Context, client *containerd.Client, container containerd.Container, checkpoint string, tty, nullIO bool, ioOpts []cio.Opt, opts ...containerd.NewTaskOpts) (containerd.Task, error) {
 	stdio := cio.NewCreator(append([]cio.Opt{cio.WithStdio}, ioOpts...)...)
-	if checkpoint == "" {
+	if checkpoint != "" {
+		im, err := client.GetImage(ctx, checkpoint)
+		if err != nil {
+			return nil, err
+		}
+		opts = append(opts, containerd.WithTaskCheckpoint(im))
+	}
 	ioCreator := stdio
 	if tty {
 		ioCreator = cio.NewCreator(append([]cio.Opt{cio.WithStdio, cio.WithTerminal}, ioOpts...)...)
@@ -82,13 +88,6 @@ func NewTask(ctx gocontext.Context, client *containerd.Client, container contain
 	}
 	return container.NewTask(ctx, ioCreator, opts...)
 }
-	im, err := client.GetImage(ctx, checkpoint)
-	if err != nil {
-		return nil, err
-	}
-	opts = append(opts, containerd.WithTaskCheckpoint(im))
-	return container.NewTask(ctx, stdio, opts...)
-}
 
 func getNewTaskOpts(context *cli.Context) []containerd.NewTaskOpts {
 	if context.Bool("no-pivot") {

linux/proc/init_state.go

@@ -194,10 +194,23 @@ func (s *createdCheckpointState) Start(ctx context.Context) error {
 	s.p.mu.Lock()
 	defer s.p.mu.Unlock()
 	p := s.p
+	sio := p.stdio
+
+	var (
+		err    error
+		socket *runc.Socket
+	)
+	if sio.Terminal {
+		if socket, err = runc.NewTempConsoleSocket(); err != nil {
+			return errors.Wrap(err, "failed to create OCI runtime console socket")
+		}
+		defer socket.Close()
+		s.opts.ConsoleSocket = socket
+	}
+
 	if _, err := s.p.runtime.Restore(ctx, p.id, p.bundle, s.opts); err != nil {
 		return p.runtimeError(err, "OCI runtime restore failed")
 	}
-	sio := p.stdio
 	if sio.Stdin != "" {
 		sc, err := fifo.OpenFifo(ctx, sio.Stdin, syscall.O_WRONLY|syscall.O_NONBLOCK, 0)
 		if err != nil {
@@ -207,7 +220,17 @@ func (s *createdCheckpointState) Start(ctx context.Context) error {
 		p.closers = append(p.closers, sc)
 	}
 	var copyWaitGroup sync.WaitGroup
-	if !sio.IsNull() {
+	if socket != nil {
+		console, err := socket.ReceiveMaster()
+		if err != nil {
+			return errors.Wrap(err, "failed to retrieve console master")
+		}
+		console, err = p.platform.CopyConsole(ctx, console, sio.Stdin, sio.Stdout, sio.Stderr, &p.wg, &copyWaitGroup)
+		if err != nil {
+			return errors.Wrap(err, "failed to start console copy")
+		}
+		p.console = console
+	} else if !sio.IsNull() {
 		if err := copyPipes(ctx, p.io, sio.Stdin, sio.Stdout, sio.Stderr, &p.wg, &copyWaitGroup); err != nil {
 			return errors.Wrap(err, "failed to start io pipe copy")
 		}
@@ -219,7 +242,6 @@ func (s *createdCheckpointState) Start(ctx context.Context) error {
 		return errors.Wrap(err, "failed to retrieve OCI runtime container pid")
 	}
 	p.pid = pid
-
 	return s.transition("running")
 }