1 files changed, 53 insertions, 34 deletions
diff --git a/lib/btrfs/io3_btree.go b/lib/btrfs/io3_btree.go
index 18df98e..db4e42c 100644
--- a/lib/btrfs/io3_btree.go
+++ b/lib/btrfs/io3_btree.go
@@ -14,49 +14,46 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
 )
 
-func (fs *FS) TreeWalk(ctx context.Context, treeID btrfsprim.ObjID, errHandle func(*btrfstree.TreeError), cbs btrfstree.TreeWalkHandler) {
-	btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeWalk(ctx, treeID, errHandle, cbs)
-}
+// This file is ordered from low-level to high-level.
 
-func (fs *FS) TreeLookup(treeID btrfsprim.ObjID, key btrfsprim.Key) (btrfstree.Item, error) {
-	return btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeLookup(treeID, key)
-}
+// btrfstree.NodeSource ////////////////////////////////////////////////////////
 
-func (fs *FS) TreeSearch(treeID btrfsprim.ObjID, fn func(key btrfsprim.Key, size uint32) int) (btrfstree.Item, error) {
-	return btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeSearch(treeID, fn)
+// ReadNode implements btrfstree.NodeSource.
+func (fs *FS) ReadNode(path btrfstree.TreePath) (*diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node], error) {
+	return btrfstree.FSReadNode(fs, path)
 }
 
-func (fs *FS) TreeSearchAll(treeID btrfsprim.ObjID, fn func(key btrfsprim.Key, size uint32) int) ([]btrfstree.Item, error) {
-	return btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeSearchAll(treeID, fn)
-}
+var _ btrfstree.NodeSource = (*FS)(nil)
 
-var _ btrfstree.TreeOperator = (*FS)(nil)
+// btrfstree.NodeFile //////////////////////////////////////////////////////////
 
 func (fs *FS) populateTreeUUIDs(ctx context.Context) {
-	if fs.cacheObjID2UUID == nil || fs.cacheUUID2ObjID == nil || fs.cacheTreeParent == nil {
-		fs.cacheObjID2UUID = make(map[btrfsprim.ObjID]btrfsprim.UUID)
-		fs.cacheUUID2ObjID = make(map[btrfsprim.UUID]btrfsprim.ObjID)
-		fs.cacheTreeParent = make(map[btrfsprim.ObjID]btrfsprim.UUID)
-		fs.TreeWalk(ctx, btrfsprim.ROOT_TREE_OBJECTID,
-			func(err *btrfstree.TreeError) {
-				// do nothing
-			},
-			btrfstree.TreeWalkHandler{
-				Item: func(_ btrfstree.TreePath, item btrfstree.Item) error {
-					itemBody, ok := item.Body.(*btrfsitem.Root)
-					if !ok {
-						return nil
-					}
-					fs.cacheObjID2UUID[item.Key.ObjectID] = itemBody.UUID
-					fs.cacheTreeParent[item.Key.ObjectID] = itemBody.ParentUUID
-					fs.cacheUUID2ObjID[itemBody.UUID] = item.Key.ObjectID
+	if fs.cacheObjID2UUID != nil && fs.cacheUUID2ObjID != nil && fs.cacheTreeParent != nil {
+		return
+	}
+	fs.cacheObjID2UUID = make(map[btrfsprim.ObjID]btrfsprim.UUID)
+	fs.cacheUUID2ObjID = make(map[btrfsprim.UUID]btrfsprim.ObjID)
+	fs.cacheTreeParent = make(map[btrfsprim.ObjID]btrfsprim.UUID)
+	fs.TreeWalk(ctx, btrfsprim.ROOT_TREE_OBJECTID,
+		func(err *btrfstree.TreeError) {
+			// do nothing
+		},
+		btrfstree.TreeWalkHandler{
+			Item: func(_ btrfstree.TreePath, item btrfstree.Item) error {
+				itemBody, ok := item.Body.(*btrfsitem.Root)
+				if !ok {
 					return nil
-				},
+				}
+				fs.cacheObjID2UUID[item.Key.ObjectID] = itemBody.UUID
+				fs.cacheTreeParent[item.Key.ObjectID] = itemBody.ParentUUID
+				fs.cacheUUID2ObjID[itemBody.UUID] = item.Key.ObjectID
+				return nil
 			},
-		)
-	}
+		},
+	)
 }
 
+// ParentTree implements btrfstree.NodeFile.
 func (fs *FS) ParentTree(tree btrfsprim.ObjID) (btrfsprim.ObjID, bool) {
 	if tree < btrfsprim.FIRST_FREE_OBJECTID || tree > btrfsprim.LAST_FREE_OBJECTID {
 		// no parent
@@ -80,6 +77,28 @@ func (fs *FS) ParentTree(tree btrfsprim.ObjID) (btrfsprim.ObjID, bool) {
 	return parentObjID, true
 }
 
-func (fs *FS) ReadNode(path btrfstree.TreePath) (*diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node], error) {
-	return btrfstree.FSReadNode(fs, path)
+var _ btrfstree.NodeFile = (*FS)(nil)
+
+// btrfstree.TreeOperator //////////////////////////////////////////////////////
+
+// TreeWalk implements btrfstree.TreeOperator.
+func (fs *FS) TreeWalk(ctx context.Context, treeID btrfsprim.ObjID, errHandle func(*btrfstree.TreeError), cbs btrfstree.TreeWalkHandler) {
+	btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeWalk(ctx, treeID, errHandle, cbs)
+}
+
+// TreeLookup implements btrfstree.TreeOperator.
+func (fs *FS) TreeLookup(treeID btrfsprim.ObjID, key btrfsprim.Key) (btrfstree.Item, error) {
+	return btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeLookup(treeID, key)
+}
+
+// TreeSearch implements btrfstree.TreeOperator.
+func (fs *FS) TreeSearch(treeID btrfsprim.ObjID, fn func(key btrfsprim.Key, size uint32) int) (btrfstree.Item, error) {
+	return btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeSearch(treeID, fn)
 }
+
+// TreeSearchAll implements btrfstree.TreeOperator.
+func (fs *FS) TreeSearchAll(treeID btrfsprim.ObjID, fn func(key btrfsprim.Key, size uint32) int) ([]btrfstree.Item, error) {
+	return btrfstree.TreeOperatorImpl{NodeSource: fs}.TreeSearchAll(treeID, fn)
+}
+
+var _ btrfstree.TreeOperator = (*FS)(nil)