1 files changed, 39 insertions, 0 deletions
diff --git a/pkg/btrfs/btrfsitem/item_uuid.go b/pkg/btrfs/btrfsitem/item_uuid.go
new file mode 100644
index 0000000..315dd70
--- /dev/null
+++ b/pkg/btrfs/btrfsitem/item_uuid.go
@@ -0,0 +1,39 @@
+package btrfsitem
+
+import (
+	"lukeshu.com/btrfs-tools/pkg/binstruct"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+)
+
+// The Key for this item is a UUID, and the item is a list of
+// subvolume IDs (ObjectIDs) that that UUID maps to.
+type UUIDMap struct { // UUID_SUBVOL=251 UUID_RECEIVED_SUBVOL=252
+	SubvolIDs []btrfstyp.ObjID
+}
+
+func (o *UUIDMap) UnmarshalBinary(dat []byte) (int, error) {
+	o.SubvolIDs = nil
+	var n int
+	for len(dat) > n {
+		var subvolID btrfstyp.ObjID
+		_n, err := binstruct.Unmarshal(dat[n:], &subvolID)
+		n += _n
+		if err != nil {
+			return n, err
+		}
+		o.SubvolIDs = append(o.SubvolIDs, subvolID)
+	}
+	return n, nil
+}
+
+func (o UUIDMap) MarshalBinary() ([]byte, error) {
+	var ret []byte
+	for _, subvolID := range o.SubvolIDs {
+		bs, err := binstruct.Marshal(subvolID)
+		ret = append(ret, bs...)
+		if err != nil {
+			return ret, err
+		}
+	}
+	return ret, nil
+}