Recommended practices for re-entrant code in C, C++

Question

I was going through a re-entrancy guide on recommended practices when writing re-entrant code.

What other references and resources cover this topic?

What lint-like tools can be used to check for these issues?

Answer 1

• Do use local variables.
• Don't use static locals or global variables, even TLS will not help you with recursion / reentrancy.
• Restore all your invariants before doing callbacks.
• Don't hold locks while you do callbacks. If you absolutely must (and I would still go looking for a way to avoid it) then make sure you know what happens if you try to re-enter your lock on the thread that already holds it. At a minimum you have to test for this, otherwise depending on the lock you'll get deadlocks or broken invariants (i.e. corruption).

Answer 2

None really. Writting non-reentering code is usually more difficult than re-entring. Just follow those simple guidelines and don't try to do anything too waky and you'll be fine.

Non-reentering code is usually written for high-performance issues.