core/rawdb: make forEach anonymous fn

core/rawdb/freezer.go

@@ -569,6 +569,30 @@ func (f *freezer) MigrateTable(kind string, isLegacy isLegacyFn, convert convert
 	if !ok {
 		return errUnknownTable
 	}
+	// forEach iterates every entry in the table serially and in order, calling `fn`
+	// with the item as argument. If `fn` returns an error the iteration stops
+	// and that error will be returned.
+	forEach := func(t *freezerTable, fn func(uint64, []byte) error) error {
+		items := atomic.LoadUint64(&t.items)
+		batchSize := uint64(1024)
+		maxBytes := uint64(1024 * 1024)
+		for i := uint64(0); i < items; {
+			if i+batchSize > items {
+				batchSize = items - i
+			}
+			data, err := t.RetrieveItems(i, batchSize, maxBytes)
+			if err != nil {
+				return err
+			}
+			for j, item := range data {
+				if err := fn(i+uint64(j), item); err != nil {
+					return err
+				}
+			}
+			i += uint64(len(data))
+		}
+		return nil
+	}
 	ancientsPath := filepath.Dir(table.index.Name())
 	// Set up new dir for the migrated table, the content of which
 	// we'll at the end move over to the ancients dir.
@@ -580,7 +604,7 @@ func (f *freezer) MigrateTable(kind string, isLegacy isLegacyFn, convert convert
 	batch := newTable.newBatch()
 	var out []byte
 	// Iterate through entries and transform them
-	table.forEach(func(i uint64, blob []byte) error {
+	forEach(table, func(i uint64, blob []byte) error {
 		if i%500000 == 0 {
 			log.Info("Processing legacy elements", "number", i)
 		}

core/rawdb/freezer_table.go

@@ -740,28 +740,3 @@ func (t *freezerTable) dumpIndex(w io.Writer, start, stop int64) {
 	}
 	fmt.Fprintf(w, "|--------------------------|\n")
 }
-
-// forEach iterates every entry in the table serially and in order, calling `fn`
-// with the item as argument. If `fn` returns an error the iteration stops
-// and that error will be returned.
-func (t *freezerTable) forEach(fn func(uint64, []byte) error) error {
-	items := atomic.LoadUint64(&t.items)
-	batchSize := uint64(1024)
-	maxBytes := uint64(1024 * 1024)
-	for i := uint64(0); i < items; {
-		if i+batchSize > items {
-			batchSize = items - i
-		}
-		data, err := t.RetrieveItems(i, batchSize, maxBytes)
-		if err != nil {
-			return err
-		}
-		for j, item := range data {
-			if err := fn(i+uint64(j), item); err != nil {
-				return err
-			}
-		}
-		i += uint64(len(data))
-	}
-	return nil
-}