The SL and Bangladesh looks to be heading into another draw as SL are still batting and have only lost 6 wickets in two days of play. If they can get to say 550+ then they could try and bowl Bangladesh out twice without batting again but it doesn't look like this pitch is offering much to the bowlers so SL might also have a hard time trying to bowl Bangladesh out twice.
The reason why Srilanka have made such a big score is that their openers Lahiru Thirimanne and Dimuth Karunaratne gave a 200 runs opening partnership and the rest of the batting lineup batted with that confidence. If Bangladesh loses early wickets it would be difficult to show the same performance even if the wicket does not favor the bowlers.