Review Request: Replace thread usage with local event loop in kio/kio/hostinfo.cpp

[Thomas Zander]

On Monday 08 August 2011 16.28.43 Dawit A wrote:
> > Apologies for still not getting it..> You stated you wanted to have a
> > timeout to avoid a blocking UI, which as
> > far as I understand you would also avoid if you don't create a new
> > method that never blocks in the first place.
>
> The uri filter plugins, which are primarly used to filter user input,e.g. user
> typing into a konqueror's address, are time critical for theobvious reasons.
> The architecture for these plugins relies on a directsynchrounous call. See
> KUriFilterPlugin in kio/kio/kurifilter.h.Perhaps looking at the parent of the
> plugin classes will help clarifythe problem for you. KUriFilter loads all
> allowed uri filter pluginsand filters the user input by invoking
> KUriFilterPlugin::filterUri.

Ok, I understand your issue;

To me there seems to be a architectural issue which you are fighting. Might be 
interesting to keep this in mind for kde5.
The architectural issue I'm seeing is that there is a singleton which has a 
method to filter and it blocks until the filtering is done.  This is at odds 
with the basic ingredient of using the network.
One is blocking and can only give a result once,  but the result might get 
better if we wait a bit longer. For example with DNS lookups.

Anyway; lets make do with what we have :)

Another solution for using a timeout can be something like the attached 
version (I didn't even try to compile it, maybe the helper object has to be 
moved to a _p.h file to get moc to run on it..)

The problem that remains with this solution is that if you have 20 plusing 
that all have a timeout, your timeouts accumulate and you still get bad 
performance.  But I don't see a way to solve that using the current 
architecture.
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