Implement support for coroutines in C++

src/framework/core/eventdispatcher.cpp

@@ -75,6 +75,16 @@ void EventDispatcher::poll()
         }
         m_pollEventsSize = m_eventList.size();
     }
+
+    for(auto it = m_coroutines.begin(); it != m_coroutines.end();) {
+        stdext::coroutine& coroutine = (*it);
+        if(coroutine.is_finished())
+            it = m_coroutines.erase(it);
+        else {
+            coroutine.resume();
+            ++it;
+        }
+    }
 }
 
 ScheduledEventPtr EventDispatcher::scheduleEvent(const std::function<void()>& callback, int delay)
@@ -114,3 +124,8 @@ EventPtr EventDispatcher::addEvent(const std::function<void()>& callback, bool p
         m_eventList.push_back(event);
     return event;
 }
+
+void EventDispatcher::addCoroutine(const stdext::coroutine& coroutine)
+{
+    m_coroutines.push_back(coroutine);
+}

src/framework/core/eventdispatcher.h

@@ -27,6 +27,7 @@
 #include "scheduledevent.h"
 
 #include <queue>
+#include <framework/stdext/coroutine.h>
 
 // @bindsingleton g_dispatcher
 class EventDispatcher
@@ -35,6 +36,7 @@ public:
     void shutdown();
     void poll();
 
+    void addCoroutine(const stdext::coroutine& coroutine);
     EventPtr addEvent(const std::function<void()>& callback, bool pushFront = false);
     ScheduledEventPtr scheduleEvent(const std::function<void()>& callback, int delay);
     ScheduledEventPtr cycleEvent(const std::function<void()>& callback, int delay);
@@ -44,6 +46,7 @@ private:
     int m_pollEventsSize;
     stdext::boolean<false> m_disabled;
     std::priority_queue<ScheduledEventPtr, std::vector<ScheduledEventPtr>, lessScheduledEvent> m_scheduledEventList;
+    std::list<stdext::coroutine> m_coroutines;
 };
 
 extern EventDispatcher g_dispatcher;

src/framework/stdext/coroutine.h

@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2010-2012 OTClient <https://github.com/edubart/otclient>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef COROUTINE_H
+#define COROUTINE_H
+
+#include <thread>
+#include <mutex>
+#include <functional>
+#include <condition_variable>
+#include <cassert>
+
+namespace stdext {
+
+//
+class coroutine
+{
+    struct codata : public stdext::shared_object {
+        std::unique_ptr<std::thread> thread;
+        std::condition_variable conditionVar;
+        std::mutex mutex;
+        std::function<void()> func;
+    };
+
+    stdext::shared_object_ptr<codata> m;
+
+    void run() {
+        assert(m->func);
+        m->func();
+        std::lock_guard<std::mutex> lock(m->mutex);
+        m->func = nullptr;
+        m->conditionVar.notify_all();
+    }
+
+public:
+    coroutine() : m(stdext::make_shared_object<codata>()) { }
+    coroutine(const coroutine& other) : m(other.m) { }
+
+    coroutine& operator=(const coroutine& other) { m = other.m; return *this; }
+
+    ~coroutine() {
+        if(m.is_unique()) {
+            m->conditionVar.notify_all();
+            m->thread->join();
+            assert(!m->func);
+        }
+    }
+
+    void create(const std::function<void()>& func) {
+        assert(!!func && !m->func);
+        m->func = func;
+    }
+
+    void yield() const {
+        std::unique_lock<std::mutex> lock(m->mutex);
+        m->conditionVar.notify_all();
+        m->conditionVar.wait(lock);
+    }
+
+    void resume() {
+        if(!m->thread) {
+            std::unique_lock<std::mutex> lock(m->mutex);
+            m->thread.reset(new std::thread(std::bind(&coroutine::run, this)));
+            m->conditionVar.wait(lock); // wait for the thread to start
+        } else {
+            std::unique_lock<std::mutex> lock(m->mutex);
+            assert(m->func);
+            m->conditionVar.notify_all();
+            m->conditionVar.wait(lock);
+        }
+    }
+
+    void join() {
+        while(!is_finished())
+            resume();
+    }
+
+    bool is_suspended() { return !!m->func; }
+    bool is_finished() { return !m->func; }
+};
+
+};
+
+#endif