Students working in restaurants that serve alcohol and pork

Many Muslim students in this country have to work to cover their tuition and living expenses, because for many of them, what they get from their families is not enough. This makes it essential for them to work as they cannot make ends meet otherwise. Often the only work they can find is in these restaurants that sell wine or offer meals containing pork or other haraam things. What is the ruling on working in these places? What is the ruling on a Muslim selling wine and pork, or producing wine and selling it to non-Muslims, given that some Muslims in these countries have taken this as their profession?