Add proper cleaning of thread for news manager

src/addons/news_manager.cpp

@@ -31,6 +31,7 @@
 #include "utils/translation.hpp"
 #include "utils/vs.hpp"
 
+#include <functional>
 #include <iostream>
 
 using namespace Online;
@@ -56,6 +57,15 @@ NewsManager::NewsManager() : m_news(std::vector<NewsMessage>())
 // ---------------------------------------------------------------------------
 NewsManager::~NewsManager()
 {
+    // If the download thread doesn't finish on time we detach the thread to
+    // avoid exception
+    if (m_download_thread.joinable())
+    {
+        if (!CanBeDeleted::canBeDeletedNow())
+            m_download_thread.detach();
+        else
+            m_download_thread.join();
+    }
 }   // ~NewsManager
 
 // ---------------------------------------------------------------------------
@@ -68,6 +78,9 @@ NewsManager::~NewsManager()
  */
 void NewsManager::init(bool force_refresh)
 {
+    if (m_download_thread.joinable())
+        return;
+
     m_force_refresh = force_refresh;
 
     // The rest (which potentially involves downloading m_news_filename) is handled
@@ -76,34 +89,21 @@ void NewsManager::init(bool force_refresh)
     // thread anyway (and the addons menu is disabled as a result).
     if(UserConfigParams::m_internet_status==RequestManager::IPERM_ALLOWED)
     {
-        pthread_attr_t  attr;
-        pthread_attr_init(&attr);
-        pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
-        pthread_t thread_id;
-        int error = pthread_create(&thread_id, &attr,
-            &NewsManager::downloadNews, this);
-        if (error)
-        {
-            Log::warn("news", "Could not create thread, error=%d", error);
-            // In this case just execute the downloading code with this thread
-            downloadNews(this);
-        }
-        pthread_attr_destroy(&attr);
+        CanBeDeleted::resetCanBeDeleted();
+        m_download_thread = std::thread(std::bind(
+            &NewsManager::downloadNews, this));
     }
-
 }   //init
 
 // ---------------------------------------------------------------------------
 /** This function submits request which will download the m_news_filename file
  *  if necessary. It is running in its own thread, so we can use blocking
  *  download calls without blocking the GUI.
- *  \param obj This is 'this' object, passed on during pthread creation.
  */
-void* NewsManager::downloadNews(void *obj)
+void NewsManager::downloadNews()
 {
     VS::setThreadName("downloadNews");
-    NewsManager *me = (NewsManager*)obj;
-    me->clearErrorMessage();
+    clearErrorMessage();
 
     std::string xml_file = file_manager->getAddonsFile(m_news_filename);
     // Prevent downloading when .part file created, which is already downloaded
@@ -118,7 +118,7 @@ void* NewsManager::downloadNews(void *obj)
                       UserConfigParams::m_news_last_updated
                           +UserConfigParams::m_news_frequency
                         < StkTime::getTimeSinceEpoch()          ||
-                      me->m_force_refresh                       ||
+                      m_force_refresh                       ||
                       !news_exists                                    )
          && UserConfigParams::m_internet_status==RequestManager::IPERM_ALLOWED
          && !file_manager->fileExists(xml_file_part);
@@ -181,7 +181,7 @@ void* NewsManager::downloadNews(void *obj)
                 const char *const curl_error = download_req->getDownloadErrorMessage();
                 error_message = StringUtils::insertValues(error_message, curl_error);
                 addons_manager->setErrorState();
-                me->setErrorMessage(error_message);
+                setErrorMessage(error_message);
                 Log::error("news", core::stringc(error_message).c_str());
             }   // hadDownloadError
         }   // hadDownloadError
@@ -202,19 +202,17 @@ void* NewsManager::downloadNews(void *obj)
     if(file_manager->fileExists(xml_file))
     {
         xml = new XMLNode(xml_file);
-        me->checkRedirect(xml);
-        me->updateNews(xml, xml_file);
+        checkRedirect(xml);
+        updateNews(xml, xml_file);
         if (addons_manager)
-            addons_manager->init(xml, me->m_force_refresh);
+            addons_manager->init(xml, m_force_refresh);
         delete xml;
     }
 
     // We can't finish stk (esp. delete the file manager) before
     // this part of the code is reached (since otherwise the file
     // manager might be access after it was deleted).
-    me->setCanBeDeleted();
-    pthread_exit(NULL);
-    return 0;  // prevent warning
+    CanBeDeleted::setCanBeDeleted();
 }   // downloadNews
 
 // ---------------------------------------------------------------------------

src/addons/news_manager.hpp

@@ -21,6 +21,7 @@
 #ifndef SERVER_ONLY
 
 #include <string>
+#include <thread>
 #include <vector>
 
 
@@ -100,11 +101,13 @@ private:
     /** True when all .xml files should be re-downloaded. */
     bool m_force_refresh;
 
+    std::thread m_download_thread;
+
     void          checkRedirect(const XMLNode *xml);
     void          updateNews(const XMLNode *xml,
                              const std::string &filename);
     bool          conditionFulfilled(const std::string &cond);
-    static void*  downloadNews(void *obj);
+    void  downloadNews();
     NewsManager();
     ~NewsManager();
 
@@ -145,9 +148,12 @@ public:
     /** Clears the error message. */
     void          clearErrorMessage() {m_error_message.setAtomic(""); }
     // ------------------------------------------------------------------------
+    void joinDownloadThreadIfExit()
+    {
+        if (CanBeDeleted::canBeDeletedNow() && m_download_thread.joinable())
+            m_download_thread.join();
+    }
 };   // NewsManager
 
-extern NewsManager *news_manager;
-
 #endif
 #endif

src/states_screens/addons_screen.cpp

@@ -503,6 +503,8 @@ void AddonsScreen::setLastSelected()
 void AddonsScreen::onUpdate(float dt)
 {
 #ifndef SERVER_ONLY
+    NewsManager::get()->joinDownloadThreadIfExit();
+
     if (m_reloading)
     {
         if(UserConfigParams::m_internet_status!=RequestManager::IPERM_ALLOWED)

src/states_screens/main_menu_screen.cpp

@@ -183,6 +183,8 @@ void MainMenuScreen::init()
 void MainMenuScreen::onUpdate(float delta)
 {
 #ifndef SERVER_ONLY
+    NewsManager::get()->joinDownloadThreadIfExit();
+
     IconButtonWidget* addons_icon = getWidget<IconButtonWidget>("addons");
     if (addons_icon != NULL)
     {

src/utils/can_be_deleted.hpp

@@ -20,9 +20,10 @@
 #define HEADER_CAN_BE_DELETED
 
 #include "utils/log.hpp"
-#include "utils/synchronised.hpp"
 #include "utils/time.hpp"
 
+#include <atomic>
+
 /** A simple class that a adds a function to wait with a timeout for a
  *  class to be ready to be deleted. It is used for objects with their
  *  own threads (e.g. RequestManager) to make sure they can be deleted.
@@ -36,25 +37,29 @@
 class CanBeDeleted
 {
 private:
-    Synchronised<bool> m_can_be_deleted;
+    std::atomic_bool m_can_be_deleted;
 public:
     /** Set this instance to be not ready to be deleted. */
-    CanBeDeleted() { m_can_be_deleted.setAtomic(false); }
+    CanBeDeleted() { m_can_be_deleted.store(false); }
     // ------------------------------------------------------------------------
     /** Sets this instance to be ready to be deleted. */
-    void setCanBeDeleted() {m_can_be_deleted.setAtomic(true); }
+    void setCanBeDeleted() { m_can_be_deleted.store(true); }
+    // ------------------------------------------------------------------------
+    void resetCanBeDeleted() { m_can_be_deleted.store(false); }
+    // ------------------------------------------------------------------------
+    bool canBeDeletedNow() { return m_can_be_deleted.load(); }
     // ------------------------------------------------------------------------
     /** Waits at most t seconds for this class to be ready to be deleted.
      *  \return true if the class is ready, false in case of a time out.
      */
     bool waitForReadyToDeleted(float waiting_time)
     {
-        if (m_can_be_deleted.getAtomic()) return true;
+        if (m_can_be_deleted.load()) return true;
         double start = StkTime::getRealTime();
         Log::verbose("Thread", "Start waiting %lf", start);
         while(1)
         {
-            if(m_can_be_deleted.getAtomic())
+            if(m_can_be_deleted.load())
             {
                 Log::verbose("Thread",
                          "Waited %lf seconds for thread to become deleteable.",