refactor the signal handlers for clarity, inverting the situation:

refactor the signal handlers for clarity, inverting the situation:
the signal handler was calling a big function which is shared between
multiple contexts -- that hides the rule that this big function has
signal safe requirements (which it fails).  now, the signal handler
contains all the code, and everyone else calls the signal handler function
as a regular function, from their (normal) contexts.
the signal handler context is the most strict, so this pattern is better.
ok florian