如何正确停止g_main_loop_run？

Question

我是第一次使用 GLib。因此，为了了解如何使用 GLib API，我编写了以下虚拟程序。

#include<glib.h>

#include<iostream>
#include<thread>
#include<chrono>

using namespace std;
using namespace std::chrono_literals;

class executor
{
private:
        GMainLoop* main_loop;
        GMainContext* worker_context;
        thread worker_thread;

        void worker_loop()
        {
                g_main_context_push_thread_default(worker_context);
                cout << "Starting main loop" << endl;
                g_main_loop_run(main_loop);
                cout << "Finished main loop" << endl;
                g_main_context_pop_thread_default(worker_context);
        }

public:
        executor()
        {
                worker_context = g_main_context_new();
                main_loop = g_main_loop_new(worker_context, false);
                worker_thread = thread(&executor::worker_loop, this);
        }

        ~executor()
        {
                g_main_loop_quit(main_loop);
                cout << "Stopped main loop from running" << endl;
                g_main_loop_unref(main_loop);
                g_main_context_unref(worker_context);
                if (worker_thread.joinable())
                {
                        worker_thread.join();
                }
        }

        void queue_callback(int (*callback)(void))
        {
                GSource* idle_source = g_idle_source_new();
                g_source_set_callback(idle_source, (GSourceFunc)callback, NULL, NULL);
                g_source_attach(idle_source, worker_context);
                g_source_unref(idle_source);
        }
};

int func1()
{
        cout << "func1 started" << endl;
        this_thread::sleep_for(5s);
        cout << "func1 finished waiting" << endl;
        return 0;
}

int func2()
{
        cout << "func2 started" << endl;
        this_thread::sleep_for(1s);
        cout << "func2 finished waiting" << endl;
        return 0;
}

int main()
{
        executor e;
        e.queue_callback(func1);
        e.queue_callback(func2);
        return 0;
}

当我运行程序时，它没有完成执行，卡住了。这是它打印的输出。

Stopped main loop from running
Starting main loop
func1 started
func1 finished waiting
func2 started
func2 finished waiting

有时它会失败并出现以下错误

Stopped main loop from running
Starting main loop

(process:16343): GLib-CRITICAL **: 10:58:54.405: g_main_loop_run: assertion 'g_atomic_int_get (&loop->ref_count) > 0' failed
Finished main loop

我猜这两个问题都会发生，因为 g_main_loop_quit 和 g_main_loop_unref 运行在 g_main_loop_run 之前。我该如何解决这些问题？

在 user7860670 的评论后编辑： 感谢 user7860670 的建议。这是现在的工作代码。

#include<glib.h>

#include<iostream>
#include<thread>
#include<chrono>

using namespace std;
using namespace std::chrono_literals;

class executor
{
private:
        GMainLoop* main_loop;
        GMainContext* worker_context;
        thread worker_thread;

        void worker_loop()
        {
                g_main_context_push_thread_default(worker_context);
                cout << "Starting main loop" << endl;
                g_main_loop_run(main_loop);
                cout << "Finished main loop" << endl;
                g_main_context_pop_thread_default(worker_context);
        }

public:
        executor()
        {
                worker_context = g_main_context_new();
                main_loop = g_main_loop_new(worker_context, false);
                worker_thread = thread(&executor::worker_loop, this);
        }

        ~executor()
        {
                cout << "Stopping main loop" << endl;
                GSource* idle_source = g_idle_source_new();
                g_source_set_callback(idle_source, (GSourceFunc)g_main_loop_quit, main_loop, NULL);
                g_source_attach(idle_source, worker_context);
                g_source_unref(idle_source);

                if (worker_thread.joinable())
                {
                        worker_thread.join();
                }
                cout << "Removing references to main loop and context" << endl;

                g_main_loop_unref(main_loop);
                g_main_context_unref(worker_context);
        }

        void queue_callback(int (*callback)(void))
        {
                GSource* idle_source = g_idle_source_new();
                g_source_set_callback(idle_source, (GSourceFunc)callback, NULL, NULL);
                g_source_attach(idle_source, worker_context);
                g_source_unref(idle_source);
        }
};

int func1()
{
        cout << "func1 started" << endl;
        this_thread::sleep_for(5s);
        cout << "func1 finished waiting" << endl;
        return 0;
}

int func2()
{
        cout << "func2 started" << endl;
        this_thread::sleep_for(1s);
        cout << "func2 finished waiting" << endl;
        return 0;
}

int main()
{
        executor e;
        e.queue_callback(func1);
        e.queue_callback(func2);
        return 0;
}

Answer 1

看起来 executor e; 可能会在工作线程开始工作之前超出范围，因为在 ~executor() 您正在等待工作线程的引用计数之前取消引用循环和上下文对象下降到 0 并且它们在工作线程工作之前被破坏。您应该以其他方式进行：等待工作线程完成，然后才取消引用循环和上下文对象。

如何正确停止g_main_loop_run？

How to stop g_main_loop_run properly?

c++

glib