Handle m_last_confirmed_item_ticks live in a thread safe way

src/items/network_item_manager.cpp

@@ -191,7 +191,11 @@ void NetworkItemManager::setItemConfirmationTime(std::weak_ptr<STKPeer> peer,
                                                  int ticks)
 {
     assert(NetworkConfig::get()->isServer());
-    if (ticks > m_last_confirmed_item_ticks.at(peer))
+    std::unique_lock<std::mutex> ul(m_live_players_mutex);
+    // Peer may get removed earlier if peer request to go back to lobby
+    if (m_last_confirmed_item_ticks.find(peer) !=
+        m_last_confirmed_item_ticks.end() &&
+        ticks > m_last_confirmed_item_ticks.at(peer))
         m_last_confirmed_item_ticks.at(peer) = ticks;
 
     // Now discard unneeded events and expired (disconnected) peer, i.e. all
@@ -210,6 +214,7 @@ void NetworkItemManager::setItemConfirmationTime(std::weak_ptr<STKPeer> peer,
             it++;
         }
     }
+    ul.unlock();
 
     // Find the last entry before the minimal confirmed time.
     // Since the event list is sorted, all events up to this

src/items/network_item_manager.hpp

@@ -27,6 +27,7 @@
 
 #include <map>
 #include <memory>
+#include <mutex>
 
 class STKPeer;
 
@@ -54,6 +55,9 @@ private:
     /** Time at which m_confirmed_state was taken. */
     int m_confirmed_state_time;
 
+    /** Allow remove or add peer live. */
+    std::mutex m_live_players_mutex;
+
     /** Stores on the server the latest confirmed tick from each client. */
     std::map<std::weak_ptr<STKPeer>, int32_t,
         std::owner_less<std::weak_ptr<STKPeer> > > m_last_confirmed_item_ticks;
@@ -99,10 +103,16 @@ public:
     virtual void undoEvent(BareNetworkString*) OVERRIDE {};
     // ------------------------------------------------------------------------
     void addLiveJoinPeer(std::weak_ptr<STKPeer> peer)
-                                     { m_last_confirmed_item_ticks[peer] = 0; }
+    {
+        std::lock_guard<std::mutex> lock(m_live_players_mutex);
+        m_last_confirmed_item_ticks[peer] = 0;
+    }
     // ------------------------------------------------------------------------
     void erasePeerInGame(std::weak_ptr<STKPeer> peer)
-                                   { m_last_confirmed_item_ticks.erase(peer); }
+    {
+        std::lock_guard<std::mutex> lock(m_live_players_mutex);
+        m_last_confirmed_item_ticks.erase(peer);
+    }
     // ------------------------------------------------------------------------
     void saveCompleteState(BareNetworkString* buffer) const;
     // ------------------------------------------------------------------------