Fix: [Network] send map to next client if current client disconnects

Also terminate creating of the savegame, as the client is gone,
there really is no need for that anymore.

(cherry picked from commit 8d199b1bbc)

src/network/network_server.cpp

@@ -280,6 +280,16 @@ NetworkRecvStatus ServerNetworkGameSocketHandler::CloseConnection(NetworkRecvSta
 		}
 	}
 
+	/* If we were transfering a map to this client, stop the savegame creation
+	 * process and queue the next client to receive the map. */
+	if (this->status == STATUS_MAP) {
+		/* Ensure the saving of the game is stopped too. */
+		this->savegame->Destroy();
+		this->savegame = nullptr;
+
+		this->CheckNextClientToSendMap(this);
+	}
+
 	NetworkAdminClientError(this->client_id, NETWORK_ERROR_CONNECTION_LOST);
 	DEBUG(net, 1, "Closed client connection %d", this->client_id);
 
@@ -590,6 +600,33 @@ NetworkRecvStatus ServerNetworkGameSocketHandler::SendWait()
 	return NETWORK_RECV_STATUS_OKAY;
 }
 
+void ServerNetworkGameSocketHandler::CheckNextClientToSendMap(NetworkClientSocket *ignore_cs)
+{
+	/* Find the best candidate for joining, i.e. the first joiner. */
+	NetworkClientSocket *best = nullptr;
+	for (NetworkClientSocket *new_cs : NetworkClientSocket::Iterate()) {
+		if (ignore_cs == new_cs) continue;
+
+		if (new_cs->status == STATUS_MAP_WAIT) {
+			if (best == nullptr || best->GetInfo()->join_date > new_cs->GetInfo()->join_date || (best->GetInfo()->join_date == new_cs->GetInfo()->join_date && best->client_id > new_cs->client_id)) {
+				best = new_cs;
+			}
+		}
+	}
+
+	/* Is there someone else to join? */
+	if (best != nullptr) {
+		/* Let the first start joining. */
+		best->status = STATUS_AUTHORIZED;
+		best->SendMap();
+
+		/* And update the rest. */
+		for (NetworkClientSocket *new_cs : NetworkClientSocket::Iterate()) {
+			if (new_cs->status == STATUS_MAP_WAIT) new_cs->SendWait();
+		}
+	}
+}
+
 /** This sends the map to the client */
 NetworkRecvStatus ServerNetworkGameSocketHandler::SendMap()
 {
@@ -649,27 +686,7 @@ NetworkRecvStatus ServerNetworkGameSocketHandler::SendMap()
 			 *  to send it is ready (maybe that happens like never ;)) */
 			this->status = STATUS_DONE_MAP;
 
-			/* Find the best candidate for joining, i.e. the first joiner. */
-			NetworkClientSocket *best = nullptr;
-			for (NetworkClientSocket *new_cs : NetworkClientSocket::Iterate()) {
-				if (new_cs->status == STATUS_MAP_WAIT) {
-					if (best == nullptr || best->GetInfo()->join_date > new_cs->GetInfo()->join_date || (best->GetInfo()->join_date == new_cs->GetInfo()->join_date && best->client_id > new_cs->client_id)) {
-						best = new_cs;
-					}
-				}
-			}
-
-			/* Is there someone else to join? */
-			if (best != nullptr) {
-				/* Let the first start joining. */
-				best->status = STATUS_AUTHORIZED;
-				best->SendMap();
-
-				/* And update the rest. */
-				for (NetworkClientSocket *new_cs : NetworkClientSocket::Iterate()) {
-					if (new_cs->status == STATUS_MAP_WAIT) new_cs->SendWait();
-				}
-			}
+			this->CheckNextClientToSendMap();
 		}
 
 		switch (this->SendPackets()) {

src/network/network_server.h

@@ -89,6 +89,8 @@ public:
 	NetworkRecvStatus CloseConnection(NetworkRecvStatus status) override;
 	void GetClientName(char *client_name, const char *last) const;
 
+	void CheckNextClientToSendMap(NetworkClientSocket *ignore_cs = nullptr);
+
 	NetworkRecvStatus SendMap();
 	NetworkRecvStatus SendErrorQuit(ClientID client_id, NetworkErrorCode errorno);
 	NetworkRecvStatus SendQuit(ClientID client_id);