Tighten the conditions for storageImageSource.cachedManifest

If the value is set to a zero-byte value, use it, instead of trying to look for a value again / elsewhere. This should not make a difference in practice, a zero-length manifest is invalid anyway; so it's just a conceptual cleanup / a microoptimization. Signed-off-by: Miloslav Trmač <mitr@redhat.com>
containers · Nov 28, 2024 · 2362cf6 · 2362cf6
1 parent 1a28c1b
commit 2362cf6
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/storage/storage_src.go b/storage/storage_src.go
@@ -247,7 +247,7 @@ func (s *storageImageSource) GetManifest(ctx context.Context, instanceDigest *di
 		}
 		return blob, manifest.GuessMIMEType(blob), err
 	}
-	if len(s.cachedManifest) == 0 {
+	if s.cachedManifest == nil {
 		// The manifest is stored as a big data item.
 		// Prefer the manifest corresponding to the user-specified digest, if available.
 		if s.imageRef.named != nil {
@@ -267,7 +267,7 @@ func (s *storageImageSource) GetManifest(ctx context.Context, instanceDigest *di
 		}
 		// If the user did not specify a digest, or this is an old image stored before manifestBigDataKey was introduced, use the default manifest.
 		// Note that the manifest may not match the expected digest, and that is likely to fail eventually, e.g. in c/image/image/UnparsedImage.Manifest().
-		if len(s.cachedManifest) == 0 {
+		if s.cachedManifest == nil {
 			cachedBlob, err := s.imageRef.transport.store.ImageBigData(s.image.ID, storage.ImageDigestBigDataKey)
 			if err != nil {
 				return nil, "", err