To diagnose legacy/trac#30235, we need to be able to see what tor is sending and receiving on the control port. I don't think that tor has any logging code for control port messages: I had a quick look, and there wasn't anything obvious. Showing each message at info level could be good, but it might also be risky? Maybe we should safe_string_client() the actual message text. nickm and catalyst are refactoring the controller code right now, so they might know where I should add the logging statements.