Calling it to check for each entries.ini would be easy, however in the current form, FGCBA forks off and starts recursing parsing all referenced INFs attempting to uncompress them on the fly, so that might cause problems with old-style CAB addons that put makecabb'd external INFs directly into i386.
I'll probably incorporate some integrator-specific changes (that will get activated when run with a new secret switch /integrator_mode) like expanding the external INF to a temporary folder while parsing ... etc.
As for checking for the presence of source files...
Does the integrator first expand all addons to the rvmtemp folder ? If so I think I can incorporate some changes in FGCBA when run in Integrator mode to check for file presence only instead of building...
I'll start making the FGCBA much more integrator plugin friendly in the next version (and add the integrator switch).
Don't worry about slowing down the integration
FGCBA is very fast in parsing INI / INF files (especially after rewriting the SimpleINIEditor classs in v0.80) and starts almost instantaneously if installed into the global assembly cache (via NGEN Install FGCBA.exe) from the %WinDir%\Microsoft.NET\Framework\v2.0.50727 folder.
I think it would make a great plugin too, i was also thinking of writing a program that would read all sysoc entries and made sure there are no duplicate entries and that all referenced files exist, that would be perfect for a integrator plugin !
@Nightwolf81 That's a whole barrage of good ideas! I'll try to implement some of those in coming versions