Auto post to twitter and facebook when log in

Hi all, is there any clue how to make this plugin can auto post to twitter and facebook anytime when logging in?

If the user log in by twitter, it will auto post in their timeline about my site. Also if they use facebook login, it will auto post in their fb wall telling that he just login in my site.

Thank you.

https://wordpress.org/plugins/wordpress-social-login/