I'm developing a cross-platform application (Win / Mac / Linux). This application loads plug-ins that I don't control as dynamic libraries, which may do various things, mostly audio and image processing.
Some of these plug-ins may use FFTW as part of their implementation details. (This is not an hypothetical case - I already have three of those). But, FFTW's fftw_plan family of function is not reentrant per the docs - they can only be called by a single thread. The problem is that some of the plug-ins I could load may call fftw_plan deep inside some thread that they would create themselves.
Is there something I can do to still make sure that things work in that case, or should I just accept that this will end up crashing ? (Putting each plug-in in its own process is not an acceptable solution for me sadly).
It turns out that FFTW provides the void fftw_make_planner_thread_safe(void) function which does ensure that plug-ins will be able to run plans in separate threads.
Calling it at the beginning of the program is enough.