Issue 5179 - Implement asynchronous executor with a controllable lifetime

src/ActiveObject.cpp

+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-present eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <AdblockPlus/ActiveObject.h>
+
+using namespace AdblockPlus;
+
+ActiveObject::ActiveObject()
+  : isRunning(true)
+{
+  thread = std::thread([this]
+  {
+    ThreadFunc();
+  });
+}
+
+ActiveObject::~ActiveObject()
+{
+  Post([this]
+  {
+    isRunning = false;
+  });
+  thread.join();
+}
+
+void ActiveObject::Post(const Call& call)
+{
+  if (!call)
+    return;
+  calls.push_back(call);
+}
+
+void ActiveObject::Post(Call&& call)
+{
+  if (!call)
+    return;
+  calls.push_back(std::move(call));
+}
+
+void ActiveObject::ThreadFunc()
+{
+  while (isRunning)
+  {
+    Call call = calls.pop_front();
+    try
+    {
+      call();
+    }
+    catch (...)
+    {
+      // do nothing, but the thread will be alive.
+    }
+  }
+}