On Mon, Apr 15, 2013 at 1:37 AM, Navin Francis navin.kurupacheril@gmail.com wrote:
I thought Tor already had some level of locking since multiple applications can connect to it at the same time via SOCKS. I completely agree about replacing the macros though.
Tor isn't multithreaded like that. Its main thread uses an asynchonous event loop. Other threads are used for cryptography-related tasks. Most of the data structures aren't locked, because they don't need to be shared between threads. Only the ones that need to get used for inter-thread communication are locked.
Personally, if I were going to try to make an in-process C API for Tor, I'd make a command queue structure that any thread could use to asynchronously send commands to the main thread, so that the only change you'd need to make in the main thread would be enough locking to handle queued commands and to queue replies. That way the codebase changes would be much simpler.
In fact, that's how the controller interface works.
peace,