[PATCH v2 1/2] win32u: Don't pass physdev to wine_get_wgl_driver() driver function.

[Jacek Caban]

Hi Paul,

On 2/1/22 18:32, Paul Gofman wrote:
> @@ -1347,13 +1349,29 @@ NTSTATUS WINAPI NtGdiDdDDICheckVidPnExclusiveOwnership( const D3DKMT_CHECKVIDPNE
>    */
>   struct opengl_funcs * CDECL __wine_get_wgl_driver( HDC hdc, UINT version )
>   {
> +    const struct gdi_dc_funcs *driver_funcs[11], **next_funcs;
>       struct opengl_funcs *ret = NULL;
>       DC * dc = get_dc_ptr( hdc );
> +    PHYSDEV physdev;
>   
>       if (dc)
>       {
> -        PHYSDEV physdev = GET_DC_PHYSDEV( dc, wine_get_wgl_driver );
> -        ret = physdev->funcs->wine_get_wgl_driver( physdev, version );
> +        next_funcs = driver_funcs;
> +        physdev = GET_DC_PHYSDEV( dc, wine_get_wgl_driver );
> +        while (physdev && next_funcs - driver_funcs < ARRAY_SIZE(driver_funcs) - 1)
> +        {
> +            *next_funcs++ = physdev->funcs;
> +            if (physdev->funcs == &null_driver) break;
> +            physdev = GET_NEXT_PHYSDEV( physdev, wine_get_wgl_driver );
> +        }
> +        *next_funcs = NULL;
> +        next_funcs = driver_funcs;
> +        while (*next_funcs)
> +        {
> +            ret = (*next_funcs)->wine_get_wgl_driver( version, &next_funcs );
> +            if (ret || !next_funcs) break;
> +            ++next_funcs;
> +        }


If the current PHYSDEV locking does not fit what we need here, it may be 
indeed a good idea to use something different here. It seems unique in 
this aspect anyway. However, it doesn't seem like hacking around PHYSDEV 
pointers like this is really what we need here. You could, for example, 
move wine_get_wgl from gdi_dc_funcs to user_driver_funcs (similar to 
what 9596e7f2a4e972c35efdca38b01d068bfc055d36 did for Vulkan) and call 
it with no PHYSDEV involved. __wine_get_wgl_driver could look roughly 
like this:


if ((hwnd = NtUserWindowFromDC( hdc )) && (ret = 
user_driver->wine_get_wgl_driver( hwnd, version )) return ret;

if (selected correct bitmap on hdc) return get_osmesa_driver( version );

return (void *)-1;


How does it look to you?


Thanks,

Jacek