ifdef mode

So, I've been using hide-ifdef-mode for C/C++ code. For example, do M-x hide-ifdef-mode and M-x hide-ifdefs and you see stuff like foo.c: #ifdef DEBUG ... #endif I'd like to see a few enhancements, for example, the '...' should be mousable. If you click on the ... you see the code. Also, the ifdef symbol could be mousable, and if clicked on could pop up a menu to define or undefine the symbol. I couldn't figure out where the ... was coming from, I guess it is coming from 'selective-display-ellipses' in redisplay.c How would I go about making this change? -jeff