Add runOnQuit (#153)

Author: marty1885

trantor/net/EventLoop.cc

@@ -111,6 +111,7 @@ void EventLoop::resetAfterFork()
 }
 EventLoop::~EventLoop()
 {
+    quit();
     assert(!looping_);
     t_loopInThisThread = nullptr;
 #ifdef __linux__
@@ -147,6 +148,13 @@ void EventLoop::removeChannel(Channel *channel)
 void EventLoop::quit()
 {
     quit_ = true;
+
+    Func f;
+    while (funcsOnQuit_.dequeue(f))
+    {
+        f();
+    }
+
     // There is a chance that loop() just executes while(!quit_) and exits,
     // then EventLoop destructs, then we are accessing an invalid object.
     // Can be fixed using mutex_ in both places.
@@ -351,4 +359,14 @@ void EventLoop::moveToCurrentThread()
     threadId_ = std::this_thread::get_id();
 }
 
+void EventLoop::runOnQuit(Func &&cb)
+{
+    funcsOnQuit_.enqueue(std::move(cb));
+}
+
+void EventLoop::runOnQuit(const Func &cb)
+{
+    funcsOnQuit_.enqueue(cb);
+}
+
 }  // namespace trantor

trantor/net/EventLoop.h

@@ -274,6 +274,15 @@ class TRANTOR_EXPORT EventLoop : NonCopyable
         return callingFuncs_;
     }
 
+    /**
+     * @brief Run functions when the event loop quits
+     *
+     * @param cb the function to run
+     * @note the function runs on the thread that quits the EventLoop
+     */
+    void runOnQuit(Func &&cb);
+    void runOnQuit(const Func &cb);
+
   private:
     void abortNotInLoopThread();
     void wakeup();
@@ -289,6 +298,7 @@ class TRANTOR_EXPORT EventLoop : NonCopyable
     bool eventHandling_;
     MpscQueue<Func> funcs_;
     std::unique_ptr<TimerQueue> timerQueue_;
+    MpscQueue<Func> funcsOnQuit_;
     bool callingFuncs_{false};
 #ifdef __linux__
     int wakeupFd_;

trantor/tests/CMakeLists.txt

@@ -18,6 +18,7 @@ add_executable(kickoff_test KickoffTest.cc)
 add_executable(dns_test DnsTest.cc)
 add_executable(delayed_ssl_server_test DelayedSSLServerTest.cc)
 add_executable(delayed_ssl_client_test DelayedSSLClientTest.cc)
+add_executable(run_on_quit_test RunOnQuitTest.cc)
 set(targets_list
     ssl_server_test
     ssl_client_test
@@ -38,7 +39,8 @@ set(targets_list
     kickoff_test
     dns_test
     delayed_ssl_server_test
-    delayed_ssl_client_test)
+    delayed_ssl_client_test
+    run_on_quit_test)
 
 set_property(TARGET ${targets_list} PROPERTY CXX_STANDARD 14)
 set_property(TARGET ${targets_list} PROPERTY CXX_STANDARD_REQUIRED ON)

trantor/tests/RunOnQuitTest.cc

@@ -0,0 +1,27 @@
+#include <trantor/net/EventLoopThread.h>
+#include <iostream>
+#include <atomic>
+#include <future>
+#ifndef _WIN32
+#include <unistd.h>
+#endif
+
+int main()
+{
+    std::atomic<bool> flag(false);
+    {
+        trantor::EventLoopThread thr;
+        thr.getLoop()->runOnQuit([&]() { flag = true; });
+        thr.run();
+        thr.getLoop()->quit();
+    }
+
+    if (flag == false)
+    {
+        std::cerr << "Test failed\n";
+    }
+    else
+    {
+        std::cout << "Success\n";
+    }
+}