.

wcfs/internal/zdata/δftail.go

@@ -40,7 +40,7 @@ package zdata
 // to avoid complexity of recomputing vδF when tracking set changes. Most of
 // ΔFtail complexity is, thus, located in ΔBtail, which implements BTree diff
 // and handles complexity of recomputing vδB when set of tracked blocks
-// changes.
+// changes after new track requests.
 //
 // Changes to ZBigFile object indicate epochs. Epochs could be:
 //
@@ -164,8 +164,8 @@ type ΔF struct {
 type ΔFile struct {
 	Rev    zodb.Tid
 	Epoch  bool   // whether file changed completely
-	Blocks setI64 // changed blocks			XXX -> ΔBlocks ?
-	Size   bool   // whether file size changed	XXX -> ΔSize?
+	Blocks setI64 // changed blocks
+	Size   bool   // whether file size changed
 }
 
 // NewΔFtail creates new ΔFtail object.
@@ -192,14 +192,14 @@ func (δFtail *ΔFtail) Tail() zodb.Tid { return δFtail.δBtail.Tail() }
 
 // Track associates file[blk]@head with tree path and zblk object.
 //
+// Path root becomes associated with the file, and the path and zblk object become tracked.
+// One root can be associated with several files (each provided on different Track calls).
+//
 // zblk can be nil, which represents a hole.
-// XXX blk=-1 is used for tracking after Size (no zblk is accessed at all).
 //
-// XXX Track adds tree path to tracked set and associates path root with file.
+// XXX blk=-1 is used for tracking after Size (no zblk is accessed at all).
 //
 // Objects in path and zblk must be with .PJar().At() == .head
-//
-// A root can be associated with several files (each provided on different Track call).
 func (δFtail *ΔFtail) Track(file *ZBigFile, blk int64, path []btree.LONode, zblk ZBlk) {
 	// XXX locking