Ensure podman ps --sync functions

The backend for `ps --sync` has been nonfunctional for a long
while now - probably since v2.0. It's questionable how useful the
flag is in modern Podman (the original case it was intended to
catch, Conmon gone via SIGKILL, should be handled now via pinging
the process with a signal to ensure it's still alive) but having
the ability to force a refresh of container state from the OCI
runtime is still useful.

Signed-off-by: Matthew Heon <mheon@redhat.com>

libpod/container_api.go

@@ -690,7 +690,7 @@ func (c *Container) Sync() error {
 
 	// If runtime knows about the container, update its status in runtime
 	// And then save back to disk
-	if c.ensureState(define.ContainerStateCreated, define.ContainerStateRunning, define.ContainerStatePaused, define.ContainerStateStopped) {
+	if c.ensureState(define.ContainerStateCreated, define.ContainerStateRunning, define.ContainerStatePaused, define.ContainerStateStopped, define.ContainerStateStopping) {
 		oldState := c.state.State
 		if err := c.ociRuntime.UpdateContainerStatus(c); err != nil {
 			return err

libpod/oci_conmon_linux.go

@@ -351,6 +351,12 @@ func (r *ConmonOCIRuntime) UpdateContainerStatus(ctr *Container) error {
 		return ctr.handleExitFile(exitFile, fi)
 	}
 
+	// Handle ContainerStateStopping - keep it unless the container
+	// transitioned to no longer running.
+	if oldState == define.ContainerStateStopping && (ctr.state.State == define.ContainerStatePaused || ctr.state.State == define.ContainerStateRunning) {
+		ctr.state.State = define.ContainerStateStopping
+	}
+
 	return nil
 }
 

pkg/ps/ps.go

@@ -136,6 +136,12 @@ func ListContainerBatch(rt *libpod.Runtime, ctr *libpod.Container, opts entities
 	)
 
 	batchErr := ctr.Batch(func(c *libpod.Container) error {
+		if opts.Sync {
+			if err := c.Sync(); err != nil {
+				return errors.Wrapf(err, "unable to update container state from OCI runtime")
+			}
+		}
+
 		conConfig = c.Config()
 		conState, err = c.State()
 		if err != nil {