[PATCH 3/8] setupapi: Implement SetupDiOpenDeviceInfoW().

[Zebediah Figura]

On 3/14/19 11:32 AM, Zhiyi Zhang wrote:
> +    /* Check class GUID */
> +    size = sizeof(classW);
> +    if (RegQueryValueExW(instanceKey, ClassGUID, NULL, NULL, (BYTE *)classW, &size))
> +        goto done;
> +
> +    classW[37] = 0;
> +    UuidFromStringW(&classW[1], &guid);
> +
> +    if (!IsEqualGUID(&guid, &set->ClassGuid))
> +    {
> +        error = ERROR_CLASS_MISMATCH;
> +        goto done;
> +    }

What if set->ClassGuid is GUID_NULL? I suspect this should match 
SetupDiCreateDeviceInfo().