I made a class in C++ today and I'm surprised it's not something that was already in the standard library
basically it's a class called LockBox<C> that holds an instance of C which is inaccessible, unless you use the Unlocker<C> class like so:
C instance;
LockBox<C> box(instance);
*pass box around to different threads*
...
*later in some thread*
Unlocker<C> instance(box);
instance->do_c_thing();
and it's thread safe C:
Unlocker<C> is a friend class that locks a mutex inside of LockBox<C> and acts as a lock_guard for that mutex. it also uses the -> and * operators to let you access members of the underlying C class
you can also make the Unlocker const so you can only access const members of C
there is a wrinkle because there is no copy constructor since std::mutex has no copy constructor, but you could potentially get around this by wrapping the mutex in a std::shared_ptr
@SuricrasiaOnline it's kinda like a capability almost
@SuricrasiaOnline so it's kinda like rust's idea of mutexes?
I like this, and agree, why the heck isn't it in std
@k thankfully it's not too difficult to implement yourself, you just need to piece together std::mutex and std::lock_guard together in a particular way
@k @SuricrasiaOnline (i was thinking the same)
@k @SuricrasiaOnline it's almost like, until rust came around no systems programming language thought about making threading… safe?!
https://github.com/blackle/Basilisk-Hunter/blob/master/src/util/LockBox.h