How to determine if code is running in signal-handler context?

Question

I just found out that someone is calling - from a signal handler - a definitely not async-signal-safe function that I wrote.

So, now I\'m curious: how to circumvent this

Answer 1

You could work out something using sigaltstack. Set up an alternative signal stack, get the stack pointer in some async-safe way, if within the alternative stack go on, otherwise abort().