This looks like the output of HexRays [1], which is the best C decompiler I've seen. Defining some structures and typing the variables would make it a lot more readable in some cases. I've used HexRays to make sense of C++ games several times, after investing enough time to define and use data types, the result looks [2] much better, but then again, that's unobfuscated and not optimized C++, not old-school "I know what I'm doing and I don't need the compiler second-guessing me" C.
Unfortunately there's still a lot decompilers can't do, mostly compiler tricks (e.g. storing a pointer to the middle of a structure instead of its beginning, and using negative offsets to access other struct members [3] - this is usually obvious when looking at it, but HexRays can't make sense of it so it falls back to raw pointer math).
If you have it installed at the moment (I don't unfortunately), you can always give it a go for comparison... The binary is apparently available from http://tuts4you.com/request.php?3011 (pass tuts4you)
Unfortunately there's still a lot decompilers can't do, mostly compiler tricks (e.g. storing a pointer to the middle of a structure instead of its beginning, and using negative offsets to access other struct members [3] - this is usually obvious when looking at it, but HexRays can't make sense of it so it falls back to raw pointer math).
[1] http://www.hex-rays.com/ [2] http://img824.imageshack.us/img824/1188/hexrayscpp.png [3] https://github.com/Laurelai/decompile-dump/blob/master/outpu...