Re: [PATCH 0/3] MR4024: uiautomationcore: COM focus change event handler event advisement support.

[Esme Povirk (＠madewokherd)]

Esme Povirk (@madewokherd) commented about dlls/uiautomationcore/tests/uiautomation.c:
> +/*
> -
> - Some versions of Windows 10 query multiple unrelated HWNDs when
> -
> - winevents are fired, this function waits for these to stop before
> -
> - continuing to the next test.
> - */
>
> +#define TIME_SINCE_LAST_CALLBACK_TIMEOUT 200
> +static BOOL wait_for_clientside_callbacks(DWORD total_timeout)
> +{
> - DWORD prev_last_callback_time, cur_time = 0;
> - DWORD start_time = GetTickCount();
> - BOOL ret;
> -
> - if (last_clientside_callback_time < start_time)
> -
>    prev_last_callback_time = start_time;
> - else
> -
>    prev_last_callback_time = last_clientside_callback_time;

We usually avoid comparisons like this for `GetTickCount()` values, because it can wrap around at 49.7 days uptime. Comparisons like `(cur_time - start_time) >= total_timeout` work correctly even in case of wraparound.

Is there any reason to have `prev_last_callback_time` at all? What if we just set last_clientside_callback_time to start_time here and used that?