Add --sync flag to podman ps

The previous commit added support for --sync to podman rm to
ensure state inconsistencies would not prevent containers from
being removed.

Add the flag to podman ps as well, so that all containers can be
forcibly synced and all state inconsistencies resolved.

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

cmd/podman/ps.go

@@ -200,6 +200,10 @@ var (
 			Usage: "Sort output by command, created, id, image, names, runningfor, size, or status",
 			Value: "created",
 		},
+		cli.BoolFlag{
+			Name:  "sync",
+			Usage: "Sync container state with OCI runtime",
+		},
 	}
 	psDescription = "Prints out information about the containers"
 	psCommand     = cli.Command{
@@ -260,6 +264,7 @@ func psCmd(c *cli.Context) error {
 		Size:      c.Bool("size"),
 		Namespace: c.Bool("namespace"),
 		Sort:      c.String("sort"),
+		Sync:      c.Bool("sync"),
 	}
 
 	filters := c.StringSlice("filter")

cmd/podman/shared/container.go

@@ -45,6 +45,7 @@ type PsOptions struct {
 	Sort      string
 	Label     string
 	Namespace bool
+	Sync      bool
 }
 
 // BatchContainerStruct is the return obkect from BatchContainer and contains
@@ -126,6 +127,12 @@ func NewBatchContainer(ctr *libpod.Container, opts PsOptions) (PsContainerOutput
 		pso       PsContainerOutput
 	)
 	batchErr := ctr.Batch(func(c *libpod.Container) error {
+		if opts.Sync {
+			if err := c.Sync(); err != nil {
+				return err
+			}
+		}
+
 		conState, err = c.State()
 		if err != nil {
 			return errors.Wrapf(err, "unable to obtain container state")

completions/bash/podman

@@ -2038,6 +2038,7 @@ _podman_ps() {
 	  --quiet -q
 	  --size -s
 	  --namespace --ns
+	  --sync
      "
      _complete_ "$options_with_args" "$boolean_options"
 }

docs/podman-ps.1.md

@@ -103,6 +103,13 @@ Valid filters are listed below:
 
 Print usage statement
 
+**--sync**
+
+Force a sync of container state with the OCI runtime.
+In some cases, a container's state in the runtime can become out of sync with Podman's state.
+This will update Podman's state based on what the OCI runtime reports.
+Forcibly syncing is much slower, but can resolve inconsistent state issues.
+
 ## EXAMPLES
 
 ```

docs/podman-rm.1.md

@@ -26,7 +26,7 @@ to run containers such as CRI-O, the last started container could be from either
 
 **--sync**
 
-Force a sync of container state with the OCI runtime before attempting to remove.
+Force a sync of container state with the OCI runtime before attempting to remove the container.
 In some cases, a container's state in the runtime can become out of sync with Podman's state,
 which can cause Podman to refuse to remove containers because it believes they are still running.
 A sync will resolve this issue.