As for tasks, 2 counters has been added to track :
* the total number of applets : nb_applets
* the number of active applets : applets_active_queue
[wt: needed for next fixes, to backport to 1.7 and 1.6]
This function is a callback made only for calls from the applet handler.
Rename it to remove confusion. It's currently called from the Lua code
but that's not correct, we should call the notify and update functions
instead otherwise it will not enable the applet again.
If an applet wakes up and causes the next one to sleep, the active list
is corrupted and cannot be scanned anymore, as the process then loops
over the next element.
In order to avoid this problem, we move the active applet list to a run
queue and reinit the active list. Only the first element of this queue
is checked, and if the element is not removed, it is removed and requeued
into the active list.
Since we're using a distinct list, if an applet wants to requeue another
applet into the active list, it properly gets added to the active list
and not to the run queue.
This stops the infinite loop issue that could be caused with Lua applets,
and in any future configuration where two applets could be attached
together.
This is not a real run queue and we're facing ugly bugs because
if this : if a an applet removes another applet from the queue,
typically the next one after itself, the list iterator loops
forever because the list's backup pointer is not valid anymore.
Before creating a run queue, let's rename this list.
The applets don't fiddle with SI_FL_WAIT_ROOM anymore, instead they indicate
what they want, possibly that they failed (eg: WAIT_ROOM), and it's done() /
update() which finally updates the WAIT_* flags according to the channels'
and stream interface's states. This solves the issue of the pauses during a
"show sess" without creating busy loops.
It's much easier to centralize this call into the I/O handler than to
do it everywhere with the risk to miss it. Applets are not allowed to
unregister themselves anyway so their SI is still present and it is
possible to update all the context.
The new function is called for each round of polling in order to call any
active appctx. For now we pick the stream interface from the appctx's
owner. At the moment there's no appctx queued yet, but we have everything
needed to queue them and remove them.
