On Mon, Jul 11, 2016 at 12:05 PM, Stefan Dösinger <stefandoesinger@gmail.com> wrote:

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Am 2016-07-10 um 23:14 schrieb Aaryaman Vasishta:
> Anyways, the vtable qi tests tests written so far show that
> querying IDirect3DRMObject from a particular interface will return
> version 1 of that interface. So technically it all comes down to
> calling
> IDirect3DRM<Interface_name>::AddDestroyCallback(&object->version1_vtable,
> ...);. In our implementation of this method (see d3drm_main.c), we
> have passed version 1 of the relevant interface while calling the
> destroy callbacks within d3drm_object_destroy. The tests seem to
> agree with that implementation so far.
Well, but you can call AddDestroyCallback on the version 3 interface too:

IDirect3DRMDevice *dev1;
IDirect3DRMDevice3 *dev3;

dev1 = create_device();
dev3 = dev1->qi(IID_IDirect3DRMDevice3);

dev1->AddDestroyCallback(...);
dev3->AddDestroyCallback(...);

The current code will always pass dev1 to the callback. It may be
correct, it may be wrong.

This is where the obj == ctxt->obj test comes in. obj is the interface passed to the callback, and ctxt->obj is the one we pass into the context, which is our interface QI'd to IDirect3DRMObject.

Now if we consider this test + the vtable QI tests, we can (in)directly prove that the interface passed to the destroy callback is always the version 1 of that interface. The tests would have failed on wine if e.g. I passed version 2 or 3 interface into the destroy callback. I agree that there are no direct tests confirming this though, but hopefully the two tests combined should be enough to confirm this.

Cheers,

Aaryaman