I wouldn't say that it is advantage India yet. India might have fought back well with the ball and restricted South Africa's lead in the first innings, but we must remember that their problems in this tour have been with their batting. They still need to set a fighting total for South Africa to chase.
So far second innings batting performance is much better than first innings. I do agree that Indian batsman is not so comfortable in playing on these fast tracks but now they got an equal chance to win this match. Just need a couple of very good partnerships to build a good total in this innings. if they can add slowly another 200+ runs in this innings then they can try to win this match. Today's first session is very important to India, if they don't lose more wickets then they can add more runs to the total.