/* * This file is part of OpenTTD. * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2. * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see . */ /** * @file network_gamelist.cpp This file handles the GameList * Also, it handles the request to a server for data about the server */ #include "../stdafx.h" #include "../debug.h" #include "../window_func.h" #include "network_internal.h" #include "network_udp.h" #include "network_gamelist.h" #include #include "../safeguards.h" NetworkGameList *_network_game_list = nullptr; /** The games to insert when the GUI thread has time for us. */ static std::atomic _network_game_delayed_insertion_list(nullptr); /** * Add a new item to the linked gamelist, but do it delayed in the next tick * or so to prevent race conditions. * @param item the item to add. Will be freed once added. */ void NetworkGameListAddItemDelayed(NetworkGameList *item) { item->next = _network_game_delayed_insertion_list.load(std::memory_order_relaxed); while (!_network_game_delayed_insertion_list.compare_exchange_weak(item->next, item, std::memory_order_acq_rel)) {} } /** Perform the delayed (thread safe) insertion into the game list */ static void NetworkGameListHandleDelayedInsert() { while (true) { NetworkGameList *ins_item = _network_game_delayed_insertion_list.load(std::memory_order_relaxed); while (ins_item != nullptr && !_network_game_delayed_insertion_list.compare_exchange_weak(ins_item, ins_item->next, std::memory_order_acq_rel)) {} if (ins_item == nullptr) break; // No item left. NetworkGameList *item = NetworkGameListAddItem(ins_item->address); if (item != nullptr) { if (StrEmpty(item->info.server_name)) { ClearGRFConfigList(&item->info.grfconfig); memset(&item->info, 0, sizeof(item->info)); strecpy(item->info.server_name, ins_item->info.server_name, lastof(item->info.server_name)); strecpy(item->info.hostname, ins_item->info.hostname, lastof(item->info.hostname)); item->online = false; } item->manually |= ins_item->manually; if (item->manually) NetworkRebuildHostList(); UpdateNetworkGameWindow(); } free(ins_item); } } /** * Add a new item to the linked gamelist. If the IP and Port match * return the existing item instead of adding it again * @param address the address of the to-be added item * @return a point to the newly added or already existing item */ NetworkGameList *NetworkGameListAddItem(NetworkAddress address) { const char *hostname = address.GetHostname(); /* Do not query the 'any' address. */ if (StrEmpty(hostname) || strcmp(hostname, "0.0.0.0") == 0 || strcmp(hostname, "::") == 0) { return nullptr; } NetworkGameList *item, *prev_item; prev_item = nullptr; for (item = _network_game_list; item != nullptr; item = item->next) { if (item->address == address) return item; prev_item = item; } item = CallocT(1); item->next = nullptr; item->address = address; if (prev_item == nullptr) { _network_game_list = item; } else { prev_item->next = item; } DEBUG(net, 4, "[gamelist] added server to list"); UpdateNetworkGameWindow(); return item; } /** * Remove an item from the gamelist linked list * @param remove pointer to the item to be removed */ void NetworkGameListRemoveItem(NetworkGameList *remove) { NetworkGameList *prev_item = nullptr; for (NetworkGameList *item = _network_game_list; item != nullptr; item = item->next) { if (remove == item) { if (prev_item == nullptr) { _network_game_list = remove->next; } else { prev_item->next = remove->next; } /* Remove GRFConfig information */ ClearGRFConfigList(&remove->info.grfconfig); free(remove); remove = nullptr; DEBUG(net, 4, "[gamelist] removed server from list"); NetworkRebuildHostList(); UpdateNetworkGameWindow(); return; } prev_item = item; } } static const uint MAX_GAME_LIST_REQUERY_COUNT = 10; ///< How often do we requery in number of times per server? static const uint REQUERY_EVERY_X_GAMELOOPS = 60; ///< How often do we requery in time? static const uint REFRESH_GAMEINFO_X_REQUERIES = 50; ///< Refresh the game info itself after REFRESH_GAMEINFO_X_REQUERIES * REQUERY_EVERY_X_GAMELOOPS game loops /** Requeries the (game) servers we have not gotten a reply from */ void NetworkGameListRequery() { NetworkGameListHandleDelayedInsert(); static uint8 requery_cnt = 0; if (++requery_cnt < REQUERY_EVERY_X_GAMELOOPS) return; requery_cnt = 0; for (NetworkGameList *item = _network_game_list; item != nullptr; item = item->next) { item->retries++; if (item->retries < REFRESH_GAMEINFO_X_REQUERIES && (item->online || item->retries >= MAX_GAME_LIST_REQUERY_COUNT)) continue; /* item gets mostly zeroed by NetworkUDPQueryServer */ uint8 retries = item->retries; NetworkUDPQueryServer(NetworkAddress(item->address)); item->retries = (retries >= REFRESH_GAMEINFO_X_REQUERIES) ? 0 : retries; } } /** * Rebuild the GRFConfig's of the servers in the game list as we did * a rescan and might have found new NewGRFs. */ void NetworkAfterNewGRFScan() { for (NetworkGameList *item = _network_game_list; item != nullptr; item = item->next) { /* Reset compatibility state */ item->info.compatible = item->info.version_compatible; for (GRFConfig *c = item->info.grfconfig; c != nullptr; c = c->next) { assert(HasBit(c->flags, GCF_COPY)); const GRFConfig *f = FindGRFConfig(c->ident.grfid, FGCM_EXACT, c->ident.md5sum); if (f == nullptr) { /* Don't know the GRF, so mark game incompatible and the (possibly) * already resolved name for this GRF (another server has sent the * name of the GRF already. */ c->name->Release(); c->name = FindUnknownGRFName(c->ident.grfid, c->ident.md5sum, true); c->name->AddRef(); c->status = GCS_NOT_FOUND; /* If we miss a file, we're obviously incompatible. */ item->info.compatible = false; } else { c->filename = f->filename; c->name->Release(); c->name = f->name; c->name->AddRef(); c->info->Release(); c->info = f->info; c->info->AddRef(); c->status = GCS_UNKNOWN; } } } InvalidateWindowClassesData(WC_NETWORK_WINDOW); }