Summer of Code 2008 officially kicked off on May 26. Within two days, I had about 1500 lines of C written for the result/value split needed for service clients to have a clean API. I started out by writing a patch that was just enough to split xmmsc_result_t into xmmsc_result_t and xmmsc_result_value_t. Then I got the suggestion to create common implementations of all the types used by XMMS2's IPC and encapsulate them in an xmmsc_value_t. That accounted for about 1400 of the 1500 lines of code. :)
As it turned out, all that work wasn't necessary and only the original patch was needed. Fellow XMMS2ers theefer (Sébastien Cevey) and nesciens (Erik Massop) took over from where the patch left off, completely separating the two structures and even converting the CLI code to use the new value_t. So now, service clients will be able to pass arguments and return values around conveniently as xmmsc_value_ts.
Now the big question in my mind is how do I merge this beast? Somehow, I need to get service client code on top of the result/value split code. Do I simply rebase the code and resolve every conflict I can see as I go? Do I squash the service client code down to a few commits? What about authorship in both cases? One thing is certain; it's going to be very hard to visualize everything that needs changing to use the new value_t. But I guess this is just another lesson in how developers do things in the real world and why small, incremental commits are so useful in preventing this situation.
So I suppose there is really only one option: to rebase and pray that it's not impossible to fix. But that's the biggest obstacle in the way of getting service clients into the next release. Anything for the t-shirt!