proxyServer: use lockListener_ to protect pushListeners_

include/opendht/dht_proxy_server.h

@@ -445,7 +445,6 @@ private:
         std::map<InfoHash, std::vector<Listener>> listeners;
         MSGPACK_DEFINE_ARRAY(listeners)
     };
-    std::mutex lockPushListeners_;
     std::map<std::string, PushListener> pushListeners_;
     proxy::ListenToken tokenPushNotif_ {0};
 #endif //OPENDHT_PUSH_NOTIFICATIONS

src/dht_proxy_server.cpp

@@ -822,7 +822,7 @@ DhtProxyServer::subscribe(restinio::request_handle_t request,
             logger_->d("[proxy:server] [subscribe %s] [client %s] [session %s]", infoHash.toString().c_str(), clientId.c_str(), sessionId.c_str());
 
         // Insert new or return existing push listeners of a token
-        std::lock_guard<std::mutex> lock(lockPushListeners_);
+        std::lock_guard<std::mutex> lock(lockListener_);
         auto& pushListener = pushListeners_[pushToken];
         auto& pushListeners = pushListener.listeners[infoHash];