Any quality C projects with readable code that one can learn from?

Do you know any good C projects made in SDL2 where I could look at the code to see how they did it, and be sure they have done their homework and do everything correctly? I know about the tutorial (I don’t say in plural because all of them except 1 are for C++, and ALL books as well), and I know about the header files, but I don’t think they are enough.

Doesn’t have to be games, can also be programs and stuff.