I'm working on porting Linux to a fiber modem (actually a family of modems), and I just finally made it to the end of what turned out to be a much more complex thing than I had anticipated.

I tried using someone else's code but I was not happy with their error handling, and as I was refactoring it at some point I realized they didn't understand the problem at all. What ensued was a 3 or 5 day bender which culminated in a 1300 line file that begins with this comment: