[#1175] metabase: Add container bucket for LOCKs

Create class of container buckets with `LOCKED` suffix. Put identifiers
of the objects of type `LOCK` to these buckets during `DB.Put`.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/local_object_storage/metabase/lock.go

@@ -0,0 +1,13 @@
+package meta
+
+import (
+	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
+)
+
+// suffix for container buckets with locked objects.
+const bucketNameSuffixLocked = invalidBase58String + "LOCKED"
+
+// returns name of the bucket with locked objects for specified container.
+func bucketNameLocked(idCnr cid.ID) []byte {
+	return []byte(idCnr.String() + bucketNameSuffixLocked)
+}

pkg/local_object_storage/metabase/put.go

@@ -198,6 +198,8 @@ func uniqueIndexes(obj *objectSDK.Object, si *objectSDK.SplitInfo, id *blobovnic
 			bucketName = tombstoneBucketName(addr.ContainerID())
 		case objectSDK.TypeStorageGroup:
 			bucketName = storageGroupBucketName(addr.ContainerID())
+		case objectSDK.TypeLock:
+			bucketName = bucketNameLocked(*addr.ContainerID())
 		default:
 			return nil, ErrUnknownObjectType
 		}