Fixed possible race conditions.

* Ensure we always create the thread-local event loop before any objects
in the thread are created, and guarantee the done handler is
immediately registered before the query can execute.
* Call the callback on emitter destruction in the worker thread, where
the eventloop lives, instead of the main thread.

With this I can no longer reproduce any deadlocks or memory corruptions
that I used to get occasionally before.

1 files changed, 3 insertions, 1 deletions

diff --git a/common/resultprovider.h b/common/resultprovider.h
index 4d985d9..a375815 100644
--- a/common/resultprovider.h
+++ b/common/resultprovider.h
@@ -100,7 +100,7 @@ public:
     {
         if (!mResultEmitter) {
             //We have to go over a separate var and return that, otherwise we'd delete the emitter immediately again
-            auto sharedPtr = QSharedPointer<ResultEmitter<T> >(new ResultEmitter<T>, [this](ResultEmitter<T> *emitter){ done(); delete emitter; });
+            auto sharedPtr = QSharedPointer<ResultEmitter<T> >(new ResultEmitter<T>, [this](ResultEmitter<T> *emitter){ mThreadBoundary->callInMainThread([this]() {done();}); delete emitter; });
             mResultEmitter = sharedPtr;
             return sharedPtr;
         }
@@ -128,6 +128,7 @@ public:
 
     void onDone(const std::function<void()> &callback)
     {
+        mThreadBoundary = QSharedPointer<ThreadBoundary>::create();
         mOnDoneCallback = callback;
     }
 
@@ -151,6 +152,7 @@ private:
     QSharedPointer<QObject> mQueryRunner;
     std::shared_ptr<void> mFacade;
     std::function<void()> mOnDoneCallback;
+    QSharedPointer<ThreadBoundary> mThreadBoundary;
 };
 
 /*