If I were a librarian, I wouldn't want to have to deal with homeless people in the library.
What about homeless people would make you feel that way?
I would be nervous telling them to get out of the library, but as a librarian I could be mean if they were homeless.
If you are a librarian, it is to be expected that homeless people will come to the library since it is a public space. If you are uncomfortable around homeless people, that is normal, but you should work on getting past it and be gracious to everyone who comes to the library.
This sounds like preaching to me and I don't like being told what to do, especially when it comes to smelly homeless people.
Homeless people are people just like you and I. It is just that they are down on their luck, so discriminating against them is not justified. Have compassion for those people around you that are in need.