Refactor OfflineMsgEngine, fix potential segfault

(@apprb take note please)

src/offlinemsgengine.cpp

@@ -23,19 +23,16 @@
 #include <QTimer>
 
 const int OfflineMsgEngine::offlineTimeout = 2000;
-QSet<OfflineMsgEngine*> OfflineMsgEngine::engines;
 QMutex OfflineMsgEngine::globalMutex;
 
 OfflineMsgEngine::OfflineMsgEngine(Friend *frnd) :
     mutex(QMutex::Recursive),
     f(frnd)
 {
-    engines.insert(this);
 }
 
 OfflineMsgEngine::~OfflineMsgEngine()
 {
-    engines.remove(this);
 }
 
 void OfflineMsgEngine::dischargeReceipt(int receipt)
@@ -106,16 +103,3 @@ void OfflineMsgEngine::removeAllReciepts()
     receipts.clear();
     undeliveredMsgs.clear();
 }
-
-void OfflineMsgEngine::processAllMsgs()
-{
-    if (globalMutex.tryLock())
-    {
-        for (auto &it : engines)
-        {
-            it->deliverOfflineMsgs();
-        }
-
-        globalMutex.unlock();
-    }
-}

src/offlinemsgengine.h

@@ -32,6 +32,7 @@ class OfflineMsgEngine : public QObject
 public:
     OfflineMsgEngine(Friend *);
     virtual ~OfflineMsgEngine();
+    static QMutex globalMutex;
 
     void dischargeReceipt(int receipt);
     void registerReceipt(int receipt, int messageID, MessageActionPtr msg, const QDateTime &timestamp = QDateTime::currentDateTime());
@@ -39,7 +40,6 @@ public:
 public slots:
     void deliverOfflineMsgs();
     void removeAllReciepts();
-    static void processAllMsgs();
 
 private:
     struct MsgPtr {
@@ -53,9 +53,7 @@ private:
     QHash<int, int> receipts;
     QMap<int, MsgPtr> undeliveredMsgs;
 
-    static QSet<OfflineMsgEngine*> engines;
     static const int offlineTimeout;
-    static QMutex globalMutex;
 };
 
 #endif // OFFLINEMSGENGINE_H

src/widget/form/chatform.cpp

@@ -105,6 +105,7 @@ ChatForm::~ChatForm()
 {
     delete netcam;
     delete callConfirm;
+    delete offlineEngine;
 }
 
 void ChatForm::setStatusMessage(QString newMessage)

src/widget/widget.cpp

@@ -225,7 +225,7 @@ void Widget::init()
     connect(addFriendForm, SIGNAL(friendRequested(QString, QString)), this, SIGNAL(friendRequested(QString, QString)));
     connect(timer, &QTimer::timeout, this, &Widget::onUserAwayCheck);
     connect(timer, &QTimer::timeout, this, &Widget::onEventIconTick);
-    connect(offlineMsgTimer, &QTimer::timeout, &OfflineMsgEngine::processAllMsgs);
+    connect(offlineMsgTimer, &QTimer::timeout, this, &Widget::processOfflineMsgs);
 
     addFriendForm->show(*ui);
 
@@ -1125,6 +1125,20 @@ void Widget::onSplitterMoved(int pos, int index)
     saveSplitterGeometry();
 }
 
+void Widget::processOfflineMsgs()
+{
+    if (OfflineMsgEngine::globalMutex.tryLock())
+    {
+        QList<Friend*> frnds = FriendList::getAllFriends();
+        for (Friend *f : frnds)
+        {
+            f->getChatForm()->getOfflineMsgEngine()->deliverOfflineMsgs();
+        }
+
+        OfflineMsgEngine::globalMutex.unlock();
+    }
+}
+
 void Widget::clearAllReceipts()
 {
     QList<Friend*> frnds = FriendList::getAllFriends();

src/widget/widget.h

@@ -132,6 +132,7 @@ private slots:
     void onEventIconTick();
     void onSetShowSystemTray(bool newValue);
     void onSplitterMoved(int pos, int index);
+    void processOfflineMsgs();
 
 private:
     void init();