Thank you for your quick answer.
That’s what I was thinking, I like your structure because you create a kind of a sandbox on a test. You can test each .c module with what stubs, fakes and mocks you want, that are enougth to test that module, without any kind of interference. The other structure seems that will always be a kind of integration test, that you can test any functions, but most of them with all other modules in the compilation.
I’ll dive more into this subject, but thanks for all your help.