handle untyped items

1 files changed, 23 insertions, 9 deletions

diff --git a/pkg/btrfs/btrfsitem/items.go b/pkg/btrfs/btrfsitem/items.go
index 3c4392e..c4ad7e9 100644
--- a/pkg/btrfs/btrfsitem/items.go
+++ b/pkg/btrfs/btrfsitem/items.go
@@ -31,12 +31,26 @@ func (o *Error) UnmarshalBinary(dat []byte) (int, error) {
 }
 
 // Rather than returning a separate error  value, return an Error item.
-func UnmarshalItem(keytyp Type, dat []byte) Item {
-	gotyp, ok := keytype2gotype[keytyp]
-	if !ok {
-		return Error{
-			Dat: dat,
-			Err: fmt.Errorf("btrfsitem.UnmarshalItem(typ=%v, dat): unknown item type", keytyp),
+func UnmarshalItem(key internal.Key, dat []byte) Item {
+	var gotyp reflect.Type
+	if key.ItemType == UNTYPED_KEY {
+		var ok bool
+		gotyp, ok = untypedObjID2gotype[key.ObjectID]
+		if !ok {
+			return Error{
+				Dat: dat,
+				Err: fmt.Errorf("btrfsitem.UnmarshalItem({ItemType:%v, ObjectID:%v}, dat): unknown object ID for untyped item",
+					key.ItemType, key.ObjectID),
+			}
+		}
+	} else {
+		var ok bool
+		gotyp, ok = keytype2gotype[key.ItemType]
+		if !ok {
+			return Error{
+				Dat: dat,
+				Err: fmt.Errorf("btrfsitem.UnmarshalItem({ItemType:%v}, dat): unknown item type", key.ItemType),
+			}
 		}
 	}
 	retPtr := reflect.New(gotyp)
@@ -44,15 +58,15 @@ func UnmarshalItem(keytyp Type, dat []byte) Item {
 	if err != nil {
 		return Error{
 			Dat: dat,
-			Err: fmt.Errorf("btrfsitem.UnmarshalItem(typ=%v, dat): %w", keytyp, err),
+			Err: fmt.Errorf("btrfsitem.UnmarshalItem({ItemType:%v}, dat): %w", key.ItemType, err),
 		}
 
 	}
 	if n < len(dat) {
 		return Error{
 			Dat: dat,
-			Err: fmt.Errorf("btrfsitem.UnmarshalItem(typ=%v, dat): left over data: got %d bytes but only consumed %d",
-				keytyp, len(dat), n),
+			Err: fmt.Errorf("btrfsitem.UnmarshalItem({ItemType:%v}, dat): left over data: got %d bytes but only consumed %d",
+				key.ItemType, len(dat), n),
 		}
 	}
 	return retPtr.Elem().Interface().(Item)