LevelDB: Seeked to start to get all the keys in HKEYS command.

leveldb.go

@@ -158,13 +158,14 @@ func (ldbs *LevelDBSession) AllKeys(hash []byte) (keys chan []byte, n int, err e
 	ro.SetFillCache(false)
 
 	it := ldbs.backend.db.NewIterator(ro)
+	it.SeekToFirst()
 	for ; it.Valid(); it.Next() {
 		n++
 	}
 
 	if err = it.GetError(); err != nil {
-		ro.Close()
 		it.Close()
+		ro.Close()
 		ldbs.backend.mutex.RUnlock()
 		return
 	}
@@ -178,6 +179,7 @@ func (ldbs *LevelDBSession) AllKeys(hash []byte) (keys chan []byte, n int, err e
 		defer close(keys)
 		it := ldbs.backend.db.NewIterator(ro)
 		defer it.Close()
+		it.SeekToFirst()
 		for ; it.Valid(); it.Next() {
 			keys <- it.Key()
 		}