Show c/storage (Buildah/CRI-O) containers in ps

The `podman ps --all` command will now show containers that
are under the control of other c/storage container systems and
the new `ps --storage` option will show only containers that are
in c/storage but are not controlled by libpod.

In the below examples, the '*working-container' entries were created
by Buildah.

```
podman ps -a
CONTAINER ID  IMAGE                             COMMAND  CREATED       STATUS                   PORTS  NAMES
9257ef8c786c  docker.io/library/busybox:latest  ls /etc  8 hours ago   Exited (0) 8 hours ago          gifted_jang
d302c81856da  docker.io/library/busybox:latest  buildah  30 hours ago  storage                         busybox-working-container
7a5a7b099d33  localhost/tom:latest              ls -alF  30 hours ago  Exited (0) 30 hours ago         hopeful_hellman
01d601fca090  localhost/tom:latest              ls -alf  30 hours ago  Exited (1) 30 hours ago         determined_panini
ee58f429ff26  localhost/tom:latest              buildah  33 hours ago  storage                         alpine-working-container

podman ps --external
CONTAINER ID  IMAGE                             COMMAND  CREATED       STATUS    PORTS  NAMES
d302c81856da  docker.io/library/busybox:latest  buildah  30 hours ago  external         busybox-working-container
ee58f429ff26  localhost/tom:latest              buildah  33 hours ago  external         alpine-working-container

```
Signed-off-by: TomSweeneyRedHat <tsweeney@redhat.com>
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

2 files changed, 13 insertions, 1 deletions

diff --git a/cmd/podman/containers/ps.go b/cmd/podman/containers/ps.go
index ebb6ed98f..2aa3b3a9b 100644
--- a/cmd/podman/containers/ps.go
+++ b/cmd/podman/containers/ps.go
@@ -13,6 +13,7 @@ import (
 	tm "github.com/buger/goterm"
 	"github.com/containers/buildah/pkg/formats"
 	"github.com/containers/podman/v2/cmd/podman/registry"
+	"github.com/containers/podman/v2/cmd/podman/utils"
 	"github.com/containers/podman/v2/cmd/podman/validate"
 	"github.com/containers/podman/v2/pkg/domain/entities"
 	"github.com/cri-o/ocicni/pkg/ocicni"
@@ -56,9 +57,9 @@ func init() {
 func listFlagSet(flags *pflag.FlagSet) {
 	flags.BoolVarP(&listOpts.All, "all", "a", false, "Show all the containers, default is only running containers")
 	flags.StringSliceVarP(&filters, "filter", "f", []string{}, "Filter output based on conditions given")
+	flags.BoolVar(&listOpts.Storage, "storage", false, "Show containers in storage not controlled by Podman")
 	flags.StringVar(&listOpts.Format, "format", "", "Pretty-print containers to JSON or using a Go template")
 	flags.IntVarP(&listOpts.Last, "last", "n", -1, "Print the n last created containers (all states)")
-	flags.BoolVar(&listOpts.Namespace, "namespace", false, "Display namespace information")
 	flags.BoolVar(&listOpts.Namespace, "ns", false, "Display namespace information")
 	flags.BoolVar(&noTrunc, "no-trunc", false, "Display the extended information")
 	flags.BoolVarP(&listOpts.Pod, "pod", "p", false, "Print the ID and name of the pod the containers are associated with")
@@ -69,6 +70,7 @@ func listFlagSet(flags *pflag.FlagSet) {
 
 	sort := validate.Value(&listOpts.Sort, "command", "created", "id", "image", "names", "runningfor", "size", "status")
 	flags.Var(sort, "sort", "Sort output by: "+sort.Choices())
+	flags.SetNormalizeFunc(utils.AliasFlags)
 }
 func checkFlags(c *cobra.Command) error {
 	// latest, and last are mutually exclusive.
@@ -102,6 +104,14 @@ func checkFlags(c *cobra.Command) error {
 	if listOpts.Watch > 0 && listOpts.Latest {
 		return errors.New("the watch and latest flags cannot be used together")
 	}
+	cfg := registry.PodmanConfig()
+	if cfg.Engine.Namespace != "" {
+		if c.Flag("storage").Changed && listOpts.Storage {
+			return errors.New("--namespace and --storage flags can not both be set")
+		}
+		listOpts.Storage = false
+	}
+
 	return nil
 }
 
diff --git a/cmd/podman/utils/alias.go b/cmd/podman/utils/alias.go
index e484461c5..ff31e82ea 100644
--- a/cmd/podman/utils/alias.go
+++ b/cmd/podman/utils/alias.go
@@ -19,6 +19,8 @@ func AliasFlags(f *pflag.FlagSet, name string) pflag.NormalizedName {
 		name = "network"
 	case "timeout":
 		name = "time"
+	case "namespace":
+		name = "ns"
 	}
 	return pflag.NormalizedName(name)
 }