Preventing zero-timer lockups when Symbian's active scheduler used

Qt 4.7 had a deferred active object scheme to give Qt active objects
some round robin behaviour with Symbian's active scheduler. Qt 4.8
has a round robin active scheduler which removed the need for any
special support in Qt's active objects. Except it has been discovered
that sometimes Symbian's active scheduler is used, and if
Qt's zero-timer active objects are running at the time, they can
prevent any other active objects from running in Symbian's scheduler,
which can cause lockups.

This change re-introduces the deferred active object system for Qt
timer active objects. This means that a timer active object will only
run once per processEvents() call when Symbian's active scheduler is
used. Qt's round robin active scheduler already prevents an
active object running more than once per processEvents(), so this
change does not affect the normal case of using Qt's round robin
scheduler.

Task-number: QTTH-1494
Reviewed-by: Shane Kearns

0 files changed, 0 insertions, 0 deletions