Always guard async callbacks

1 files changed, 40 insertions, 0 deletions

diff --git a/framework/src/async.h b/framework/src/async.h
new file mode 100644
index 00000000..34233244
--- /dev/null
+++ b/framework/src/async.h
@@ -0,0 +1,40 @@
+/*
+    Copyright (c) 2017 Christian Mollekopf <mollekopf@kolabsys.com>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+#pragma once
+
+#include <QtConcurrent/QtConcurrentRun>
+#include <QFuture>
+#include <QFutureWatcher>
+#include <QPointer>
+
+template<typename T>
+void asyncRun(QObject *object, std::function<T()> run, std::function<void(T)> continuation)
+{
+    auto guard = QPointer<QObject>{object};
+    auto future = QtConcurrent::run(run);
+    auto watcher = new QFutureWatcher<T>;
+    QObject::connect(watcher, &QFutureWatcher<T>::finished, watcher, [watcher, continuation, guard]() {
+        if (guard) {
+            continuation(watcher->future().result());
+        }
+        delete watcher;
+    });
+    watcher->setFuture(future);
+}
+