Mesh with Holes

Ok here is the deal. I have a Polygon and want to create a Mesh out of it. No Problem just assign the right triangles and im good to go. Thing is I want to Create a Mesh out of several Polygons. One Polygon ist the wall the others are Openings inside this Wall. I know wich are the openings and which is the big one but nothing else. Is there any script or algortihm that assignes the triangles correctly? Or do I need to build it from Scratch