Theos: How to hook a method with a block argument? (CDUnknownBlockType)

Question

%hook HTTPClient
- (CDUnknownBlockType)completionForSuccess:(CDUnknownBlockType)arg1 {
}
%end

I am wondering what to place in place of CDUnknownBlockType here (generated from class-dump). I do not know the arguments to the block so I cannot put the exact signature. Is it possible to instead use MSHookMessage with a generic pointer as the argument? A generic void * pointer did not work for me here as the message does not match.

Is there a way to get the block's signature?

Answer 1

You can replace the CDUnknownBlockType with id. It's as simple as that.