update value

weed/util/skiplist/skiplist.go

@@ -1,5 +1,7 @@
 package skiplist
 
+// adapted from https://github.com/MauriceGit/skiplist/blob/master/skiplist.go
+
 import (
 	"bytes"
 	"fmt"
@@ -402,6 +404,17 @@ func (t *SkipList) Prev(e *SkipListElement) *SkipListElement {
 	return e.Prev.Load()
 }
 
+// ChangeValue can be used to change the actual value of a node in the skiplist
+// without the need of Deleting and reinserting the node again.
+// Be advised, that ChangeValue only works, if the actual key from ExtractKey() will stay the same!
+// ok is an indicator, wether the value is actually changed.
+func (t *SkipList) ChangeValue(e *SkipListElement, newValue []byte) (ok bool) {
+	// The key needs to stay correct, so this is very important!
+	e.Value = newValue
+	e.Save()
+	return true
+}
+
 // String returns a string format of the skiplist. Useful to get a graphical overview and/or debugging.
 func (t *SkipList) println() {