Merge pull request #31 from AntelopeIO/dtor_order_40

fix appbase destruction order: destroy executor after destroying plugins

application_base.cpp

@@ -88,8 +88,8 @@ class application_impl {
       std::optional<boost::asio::io_context> _signal_catching_io_ctx;
 };
 
-application_base::application_base()
-:my(new application_impl()){
+application_base::application_base(std::shared_ptr<void>&& e) :
+ executor_ptr(std::move(e)), my(new application_impl()){
    register_config_type<std::string>();
    register_config_type<bool>();
    register_config_type<unsigned short>();

include/appbase/application_base.hpp

@@ -290,7 +290,10 @@ class application_base {
    }
    ///@}
 
-   application_base(); ///< protected because application is a singleton that should be accessed via instance()
+   application_base(std::shared_ptr<void>&& e); ///< protected because application is a singleton that should be accessed via instance()
+
+   /// !!! must be dtor'ed after plugins
+   std::shared_ptr<void> executor_ptr;
 
 private:
    // members are ordered taking into account that the last one is destructed first
@@ -350,15 +353,15 @@ class application_t : public application_base {
     */
    template <typename Func>
    auto post(int priority, Func&& func) {
-      return executor_.post(priority, std::forward<Func>(func));
+      return executor().post(priority, std::forward<Func>(func));
    }
 
    /**
     *  Wait until quit(), SIGINT or SIGTERM and then shutdown.
     *  Should only be executed from one thread.
     */
    void exec() {
-      application_base::exec(executor_);
+      application_base::exec(executor());
    }
 
    /**
@@ -367,25 +370,24 @@ class application_t : public application_base {
     * @return
     */
    boost::asio::io_service& get_io_service() {
-      return executor_.get_io_service();
+      return executor().get_io_service();
    }
 
    void startup() {
       application_base::startup(get_io_service());
    }
 
-   application_t() {
+   application_t() : application_base(std::make_shared<executor_t>()) {
       set_stop_executor_cb([&]() { get_io_service().stop(); });
-      set_post_cb([&](int prio, std::function<void()> cb) { executor_.post(prio, std::move(cb)); });
+      set_post_cb([&](int prio, std::function<void()> cb) { executor().post(prio, std::move(cb)); });
    }
 
-   executor_t& executor() {
-      return executor_;
+   executor_t& executor() const {
+      return *static_cast<executor_t*>(executor_ptr.get());
    }
 
 private:
    inline static std::unique_ptr<application_t> app_instance;
-   executor_t executor_;
 };