Andreas Beck wrote:
> > In the depth My question was why after calling poll(I call it with 0 time
> > delay) the queued function shows only one message we have inside of
> > queue but actually there are many (inside of some internal buffers).
>
> If that is the case, this is a bug and should be fixed.
>
> > I think poll function really poll only one message for each message type
> > per one call, does not it?
>
> No. It should check and queue all attached inputs, and all inputs should
> read their sources until they are drained.
Well, this is only a problem for broken or really strange apps, but
I think we should still provide a way around it:
Let gq be the number of events queued in LibGII and kq be the number
of events queued in the kernel.
Initial state: gq = 0, kq = 3
giiEventPoll() is called ==> fetches all events ==> gq = 3; kq = 0;
giiEventRead() is called, but only twice ==> gq = 1; kq = 0;
Now the user moves the mouse arround ==> gq = 1; kq = 5;
giiEventPoll() is called ==> as gq > 0 no events are fetched from kq
into gq. This is 100% correct due to performance reasons, BUT:
When giiEventsQueued() is called and returns the number of events in
the queue you get 1 allthough there are more events that could be
read.
My suggestion is that we add a new function
int giiQueuedAfterPoll(struct gii_input *inp, gii_event_mask mask);
which will first poll all relevant input sources, regardless of the
number of events queued, and then return the number of events available.
When I think of it we should definitely add this function, because
it will allow the following common code:
struct timeval tv = { 0, 0};
if (giiEventPoll(inp, mask, &tv)) {
n = giiEventsQueued(inp, mask);
while (n--) {
giiEventRead(inp, &ev, mask);
process_event(%ev);
}
}
to be replaced with:
n = giiQueuedAfterPoll(inp, mask);
while (n--) {
giiEventRead(inp, &ev, mask);
process_event(%ev);
}
Unless there are any objections or suggestions for a better name
I'll add this function to LibGII (and it's companion in LibGGI).
//Marcus
--
-------------------------------+------------------------------------
Marcus Sundberg | http://www.stacken.kth.se/~mackan/
Royal Institute of Technology | Phone: +46 707 295404
Stockholm, Sweden | E-Mail: [EMAIL PROTECTED]
