SDL_JoystickGetAttached sets error "Joystick hasn't been opened yet", but SDL_GameControllerGetAttached is silent

[AntTheAlchemist]

As title. Why does one the JoystickGetAttached behave differently to the GameControllerGetAttached?

This code will trigger it:

SDL_JoystickGetAttached(SDL_JoystickFromInstanceID(SDL_JoystickGetDeviceInstanceID(0)));

Have at least 1 joystick plugged in. The error is triggered by SDL_JoystickGetAttached(). It's perfectly legal to get an instance ID before opening a joystick, and then get a joystick before it's opened with said ID, then check if that joystick is opened. There's no SDL_JoystickIsOpen(), so this is the only way I can do it. This works silently with SDL_GameControllerGetAttached(), so the different behaviour must be a bug.

[flibitijibibo]

I imagine this is why it does that: https://github.com/libsdl-org/SDL/blob/main/src/joystick/SDL_gamecontroller.c#L2342-L2343

If you change it to something like (gamecontroller == NULL) ? NULL : gamecontroller->joystick it will probably emit the same message.

[AntTheAlchemist]

Thanks guys.

To be pedantic and tidy, we can now safely remove

    if (!gamecontroller)
        return SDL_FALSE;

from SDL_GameControllerGetAttached().

[slouken]

No, it would crash if we did that. :)

[AntTheAlchemist]

No, it would crash if we did that. :)

It won't now, because SDL_JoystickGetAttached() checks for null :P [delete delete delete]

Okay, yes it will crash, ignore me lol