specgen,run: support running container from valid manifest list

Following PR adds support for running containers from a manifest list
present on localstorage. Before this PR podman only supports running
containers from valid images but not from manifest list.

So `podman run -it --platform <some> <manifest-list> command` should
become functional now and users should be able to resolve images on the
bases of provided `--platform` string.

Example
```
podman manifest create test
podman build --platform linux/amd64,linux/arm64 --manifest test .
podman run --rm --platform linux/arm64/v8 test uname -a
```

Closes: https://github.com/containers/podman/issues/14773

Signed-off-by: Aditya R <arajan@redhat.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/pkg/specgen/generate/container.go b/pkg/specgen/generate/container.go
index 30c759495..8fdd87adf 100644
--- a/pkg/specgen/generate/container.go
+++ b/pkg/specgen/generate/container.go
@@ -38,10 +38,19 @@ func getImageFromSpec(ctx context.Context, r *libpod.Runtime, s *specgen.SpecGen
 	}
 
 	// Need to look up image.
-	image, resolvedName, err := r.LibimageRuntime().LookupImage(s.Image, nil)
+	lookupOptions := &libimage.LookupImageOptions{ManifestList: true}
+	image, resolvedName, err := r.LibimageRuntime().LookupImage(s.Image, lookupOptions)
 	if err != nil {
 		return nil, "", nil, err
 	}
+	manifestList, err := image.ToManifestList()
+	// only process if manifest list found otherwise expect it to be regular image
+	if err == nil {
+		image, err = manifestList.LookupInstance(ctx, s.ImageArch, s.ImageOS, s.ImageVariant)
+		if err != nil {
+			return nil, "", nil, err
+		}
+	}
 	s.SetImage(image, resolvedName)
 	inspectData, err := image.Inspect(ctx, nil)
 	if err != nil {