The quoted code might not have been pretty, but it was by no means obfuscated. I would say about standard for older C.
Unless it's assembler, I don't expect much comments within the code, but appreciate if there is (as long as it (still) matches the code, which sadly isn't a given). More important to me is documentation outside the code -- some kind of product requirement document, worklog, changelog etc. . Is the code under some version control (if not, that might be the answer you're looking for), how do the check-in comments look like? Is the motivation of changes documented (or does the author only state the obvious, as in "added foo() to bar.c", which is all too common or mysterious, as in "fixed baz()")? Is there a defect database (for larger projects IMHO a must)? Is that defect database consistently(!) referred to in the version control check-in comments?
And yes, I chose to decline a work-offer once, but that involved a collection of shell scripts a different company already declined to work on ...