GUI: Implement stopping the compare.

Threads must be exited from check cleanly even though it takes small amount of time. Just terminating thread can have unpredictable side-effects (even weird crashes).

gui/checkthread.cpp

@@ -40,10 +40,11 @@ void CheckThread::Check(Settings settings)
 
 void CheckThread::run()
 {
+    mState = Running;
     QString file;
     file = mResult.GetNextFile();
 
-    while (!file.isEmpty())
+    while (!file.isEmpty() && mState == Running)
     {
         qDebug() << "Checking file" << file;
         mCppcheck.addFile(file.toStdString());
@@ -51,11 +52,18 @@ void CheckThread::run()
         mCppcheck.clearFiles();
         emit FileChecked(file);
 
-        file = mResult.GetNextFile();
+        if (mState == Running)
+            file = mResult.GetNextFile();
     }
+    if (mState == Running)
+        mState = Ready;
+	else
+        mState = Stopped;
 
     emit Done();
 }
 
-
-
+void CheckThread::stop()
+{
+    mState = Stopping;
+}

gui/checkthread.h

@@ -49,6 +49,8 @@ public:
     */
     void run();
 
+    void stop();
+
 
 signals:
 
@@ -60,6 +62,27 @@ signals:
 
     void FileChecked(const QString &file);
 protected:
+
+    /**
+    * @brief States for the check thread.
+    * Whole purpose of these states is to allow stopping of the checking. When
+    * stopping we say for the thread (Stopping) that "stop when current check
+    * has been completed. Thread must be stopped cleanly, just terminating thread
+    * likely causes unpredictable side-effedts.
+    */
+    enum State
+    {
+        Running, /**< The thread is checking. */
+        Stopping, /**< The thread will stop after current work. */
+        Stopped, /**< The thread has been stopped. */
+        Ready, /**< The thread is ready. */
+    };
+
+    /**
+    * @brief Thread's current execution state.
+    */
+    State mState;
+
     ThreadResult &mResult;
     /**
     * @brief Cppcheck itself

gui/mainwindow.cpp

@@ -105,8 +105,7 @@ MainWindow::MainWindow() :
 
     connect(&mActionReCheck, SIGNAL(triggered()), this, SLOT(ReCheck()));
 
-    //TODO: This crashed
-    //connect(&mActionStop, SIGNAL(triggered()), &mThread, SLOT(Stop()));
+    connect(&mActionStop, SIGNAL(triggered()), &mThread, SLOT(Stop()));
     connect(&mActionSave, SIGNAL(triggered()), this, SLOT(Save()));
 
     connect(&mActionAbout, SIGNAL(triggered()), this, SLOT(About()));

gui/threadhandler.cpp

@@ -124,7 +124,7 @@ void ThreadHandler::Stop()
 {
     for (int i = 0;i < mThreads.size();i++)
     {
-        mThreads[i]->terminate();
+        mThreads[i]->stop();
     }
 }