Allowing symbian cleanup code in thread started and finished slots

The run() function of QThread was inside a TRAP, but the started() and
finished() signals were emitted outside of a TRAP so could not contain
Symbian cleanup stack code. This broke compatability with some apps,
as the older pthread based implementation had the whole main thread
function running inside a TRAP.

The started and finished signals are now emitted inside TRAPs, with
enhanced leave/exception handling code.

Task-number: ou1cimx1#979704
Change-Id: I9b4e50b1085494b5fd5e05efa11739ce19ff26fb
Reviewed-by: Shane Kearns <ext-shane.2.kearns@nokia.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/src/corelib/thread/qthread_symbian.cpp b/src/corelib/thread/qthread_symbian.cpp
index fc0e4509eb..fd551ffb58 100644
--- a/src/corelib/thread/qthread_symbian.cpp
+++ b/src/corelib/thread/qthread_symbian.cpp
@@ -337,18 +337,26 @@ void *QThreadPrivate::start(void *arg)
     // ### TODO: allow the user to create a custom event dispatcher
     createEventDispatcher(data);
 
-    emit thr->started();
     TRAPD(err, {
         try {
+            emit thr->started();
             thr->run();
         } catch (const std::exception& ex) {
             qWarning("QThreadPrivate::start: Thread exited on exception %s", ex.what());
+            User::Leave(KErrGeneral);   // leave to force cleanup stack cleanup
         }
     });
     if (err)
         qWarning("QThreadPrivate::start: Thread exited on leave %d", err);
 
-    QThreadPrivate::finish(arg);
+    // finish emits signals which should be wrapped in a trap for Symbian code, but otherwise ignore leaves and exceptions.
+    TRAP(err, {
+        try {
+            QThreadPrivate::finish(arg);
+        } catch (const std::exception& ex) {
+            User::Leave(KErrGeneral);   // leave to force cleanup stack cleanup
+        }
+    });
 
     delete cleanup;