src/command.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * 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.
   4  * 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.
   5  * 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 <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file command.cpp Handling of commands. */
   9
  10 #include "stdafx.h"
  11 #include "landscape.h"
  12 #include "error.h"
  13 #include "gui.h"
  14 #include "command_func.h"
  15 #include "network/network_type.h"
  16 #include "network/network.h"
  17 #include "genworld.h"
  18 #include "strings_func.h"
  19 #include "texteff.hpp"
  20 #include "town.h"
  21 #include "timer/timer_game_economy.h"
  22 #include "company_func.h"
  23 #include "company_base.h"
  24 #include "signal_func.h"
  25 #include "core/backup_type.hpp"
  26 #include "object_base.h"
  27 #include "autoreplace_cmd.h"
  28 #include "company_cmd.h"
  29 #include "depot_cmd.h"
  30 #include "economy_cmd.h"
  31 #include "engine_cmd.h"
  32 #include "goal_cmd.h"
  33 #include "group_cmd.h"
  34 #include "industry_cmd.h"
  35 #include "league_cmd.h"
  36 #include "landscape_cmd.h"
  37 #include "misc_cmd.h"
  38 #include "news_cmd.h"
  39 #include "object_cmd.h"
  40 #include "order_cmd.h"
  41 #include "rail_cmd.h"
  42 #include "road_cmd.h"
  43 #include "roadveh_cmd.h"
  44 #include "settings_cmd.h"
  45 #include "signs_cmd.h"
  46 #include "station_cmd.h"
  47 #include "story_cmd.h"
  48 #include "subsidy_cmd.h"
  49 #include "terraform_cmd.h"
  50 #include "timetable_cmd.h"
  51 #include "town_cmd.h"
  52 #include "train_cmd.h"
  53 #include "tree_cmd.h"
  54 #include "tunnelbridge_cmd.h"
  55 #include "vehicle_cmd.h"
  56 #include "viewport_cmd.h"
  57 #include "water_cmd.h"
  58 #include "waypoint_cmd.h"
  59 #include "misc/endian_buffer.hpp"
  60 #include "string_func.h"
  61
  62 #include "table/strings.h"
  63
  64 #include "safeguards.h"
  65
  66
  67 int RecursiveCommandCounter::_counter = 0;
  68
  69
  70 /**
  71  * Define a command with the flags which belongs to it.
  72  *
  73  * This struct connects a command handler function with the flags created with
  74  * the #CMD_AUTO, #CMD_OFFLINE and #CMD_SERVER values.
  75  */
  76 struct CommandInfo {
  77         const char *name;   ///< A human readable name for the procedure
  78         CommandFlags flags; ///< The (command) flags to that apply to this command
  79         CommandType type;   ///< The type of command.
  80 };
  81 /* Helpers to generate the master command table from the command traits. */
  82 template <typename T>
  83 inline constexpr CommandInfo CommandFromTrait() noexcept { return { T::name, T::flags, T::type }; };
  84
  85 template<typename T, T... i>
  86 inline constexpr auto MakeCommandsFromTraits(std::integer_sequence<T, i...>) noexcept {
  87         return std::array<CommandInfo, sizeof...(i)>{{ CommandFromTrait<CommandTraits<static_cast<Commands>(i)>>()... }};
  88 }
  89
  90 /**
  91  * The master command table
  92  *
  93  * This table contains all possible CommandProc functions with
  94  * the flags which belongs to it. The indices are the same
  95  * as the value from the CMD_* enums.
  96  */
  97 static constexpr auto _command_proc_table = MakeCommandsFromTraits(std::make_integer_sequence<std::underlying_type_t<Commands>, CMD_END>{});
  98
  99
 100 /**
 101  * This function range-checks a cmd.
 102  *
 103  * @param cmd The integer value of a command
 104  * @return true if the command is valid (and got a CommandProc function)
 105  */
 106 bool IsValidCommand(Commands cmd)
 107 {
 108         return cmd < _command_proc_table.size();
 109 }
 110
 111 /**
 112  * This function mask the parameter with CMD_ID_MASK and returns
 113  * the flags which belongs to the given command.
 114  *
 115  * @param cmd The integer value of the command
 116  * @return The flags for this command
 117  */
 118 CommandFlags GetCommandFlags(Commands cmd)
 119 {
 120         assert(IsValidCommand(cmd));
 121
 122         return _command_proc_table[cmd].flags;
 123 }
 124
 125 /**
 126  * This function mask the parameter with CMD_ID_MASK and returns
 127  * the name which belongs to the given command.
 128  *
 129  * @param cmd The integer value of the command
 130  * @return The name for this command
 131  */
 132 const char *GetCommandName(Commands cmd)
 133 {
 134         assert(IsValidCommand(cmd));
 135
 136         return _command_proc_table[cmd].name;
 137 }
 138
 139 /**
 140  * Returns whether the command is allowed while the game is paused.
 141  * @param cmd The command to check.
 142  * @return True if the command is allowed while paused, false otherwise.
 143  */
 144 bool IsCommandAllowedWhilePaused(Commands cmd)
 145 {
 146         /* Lookup table for the command types that are allowed for a given pause level setting. */
 147         static const int command_type_lookup[] = {
 148                 CMDPL_ALL_ACTIONS,     ///< CMDT_LANDSCAPE_CONSTRUCTION
 149                 CMDPL_NO_LANDSCAPING,  ///< CMDT_VEHICLE_CONSTRUCTION
 150                 CMDPL_NO_LANDSCAPING,  ///< CMDT_MONEY_MANAGEMENT
 151                 CMDPL_NO_CONSTRUCTION, ///< CMDT_VEHICLE_MANAGEMENT
 152                 CMDPL_NO_CONSTRUCTION, ///< CMDT_ROUTE_MANAGEMENT
 153                 CMDPL_NO_CONSTRUCTION, ///< CMDT_OTHER_MANAGEMENT
 154                 CMDPL_NO_ACTIONS,      ///< CMDT_COMPANY_SETTING
 155                 CMDPL_NO_ACTIONS,      ///< CMDT_SERVER_SETTING
 156                 CMDPL_NO_ACTIONS,      ///< CMDT_CHEAT
 157         };
 158         static_assert(lengthof(command_type_lookup) == CMDT_END);
 159
 160         assert(IsValidCommand(cmd));
 161         return _game_mode == GM_EDITOR || command_type_lookup[_command_proc_table[cmd].type] <= _settings_game.construction.command_pause_level;
 162 }
 163
 164 /**
 165  * Prepare for calling a command proc.
 166  * @param top_level Top level of command execution, i.e. command from a command.
 167  * @param test Test run of command?
 168  */
 169 void CommandHelperBase::InternalDoBefore(bool top_level, bool test)
 170 {
 171         if (top_level) _cleared_object_areas.clear();
 172         if (test) SetTownRatingTestMode(true);
 173 }
 174
 175 /**
 176  * Process result after calling a command proc.
 177  * @param[in,out] res Command result, may be modified.
 178  * @param flags Command flags.
 179  * @param top_level Top level of command execution, i.e. command from a command.
 180  * @param test Test run of command?
 181  */
 182 void CommandHelperBase::InternalDoAfter(CommandCost &res, DoCommandFlag flags, bool top_level, bool test)
 183 {
 184         if (test) {
 185                 SetTownRatingTestMode(false);
 186
 187                 if (res.Succeeded() && top_level && !(flags & DC_QUERY_COST) && !(flags & DC_BANKRUPT)) {
 188                         CheckCompanyHasMoney(res); // CheckCompanyHasMoney() modifies 'res' to an error if it fails.
 189                 }
 190         } else {
 191                 /* If top-level, subtract the money. */
 192                 if (res.Succeeded() && top_level && !(flags & DC_BANKRUPT)) {
 193                         SubtractMoneyFromCompany(res);
 194                 }
 195         }
 196 }
 197
 198 /**
 199  * Decide what to do with the command depending on current game state.
 200  * @param cmd Command to execute.
 201  * @param flags Command flags.
 202  * @param tile Tile of command execution.
 203  * @param err_message Message prefix to show on error.
 204  * @param network_command Does this command come from the network?
 205  * @return error state + do only cost estimation? + send to network only?
 206  */
 207 std::tuple<bool, bool, bool> CommandHelperBase::InternalPostBefore(Commands cmd, CommandFlags flags, TileIndex tile, StringID err_message, bool network_command)
 208 {
 209         /* Cost estimation is generally only done when the
 210          * local user presses shift while doing something.
 211          * However, in case of incoming network commands,
 212          * map generation or the pause button we do want
 213          * to execute. */
 214         bool estimate_only = _shift_pressed && IsLocalCompany() && !_generating_world && !network_command && !(flags & CMD_NO_EST);
 215
 216         /* We're only sending the command, so don't do
 217          * fancy things for 'success'. */
 218         bool only_sending = _networking && !network_command;
 219
 220         if (_pause_mode != PM_UNPAUSED && !IsCommandAllowedWhilePaused(cmd) && !estimate_only) {
 221                 ShowErrorMessage(err_message, STR_ERROR_NOT_ALLOWED_WHILE_PAUSED, WL_INFO, TileX(tile) * TILE_SIZE, TileY(tile) * TILE_SIZE);
 222                 return { true, estimate_only, only_sending };
 223         } else {
 224                 return { false, estimate_only, only_sending };
 225         }
 226 }
 227
 228 /**
 229  * Process result of executing a command, possibly displaying any error to the player.
 230  * @param res Command result.
 231  * @param tile Tile of command execution.
 232  * @param estimate_only Is this just cost estimation?
 233  * @param only_sending Was the command only sent to network?
 234  * @param err_message Message prefix to show on error.
 235  * @param my_cmd Is the command from this client?
 236  */
 237 void CommandHelperBase::InternalPostResult(const CommandCost &res, TileIndex tile, bool estimate_only, bool only_sending, StringID err_message, bool my_cmd)
 238 {
 239         int x = TileX(tile) * TILE_SIZE;
 240         int y = TileY(tile) * TILE_SIZE;
 241
 242         if (res.Failed()) {
 243                 /* Only show the error when it's for us. */
 244                 if (estimate_only || (IsLocalCompany() && err_message != 0 && my_cmd)) {
 245                         ShowErrorMessage(err_message, x, y, res);
 246                 }
 247         } else if (estimate_only) {
 248                 ShowEstimatedCostOrIncome(res.GetCost(), x, y);
 249         } else if (!only_sending && tile != 0 && IsLocalCompany() && _game_mode != GM_EDITOR) {
 250                 /* Only show the cost animation when we did actually
 251                  * execute the command, i.e. we're not sending it to
 252                  * the server, when it has cost the local company
 253                  * something. Furthermore in the editor there is no
 254                  * concept of cost, so don't show it there either. */
 255                 ShowCostOrIncomeAnimation(x, y, GetSlopePixelZ(x, y), res.GetCost());
 256         }
 257 }
 258
 259 /** Helper to make a desync log for a command. */
 260 void CommandHelperBase::LogCommandExecution(Commands cmd, StringID err_message, const CommandDataBuffer &args, bool failed)
 261 {
 262         Debug(desync, 1, "{}: {:08x}; {:02x}; {:02x}; {:08x}; {:08x}; {} ({})", failed ? "cmdf" : "cmd", (uint32_t)TimerGameEconomy::date.base(), TimerGameEconomy::date_fract, (int)_current_company, cmd, err_message, FormatArrayAsHex(args), GetCommandName(cmd));
 263 }
 264
 265 /**
 266  * Prepare for the test run of a command proc call.
 267  * @param cmd_flags Command flags.
 268  * @param[in,out] cur_company Backup of current company at start of command execution.
 269  * @return True if test run can go ahead, false on error.
 270  */
 271 bool CommandHelperBase::InternalExecutePrepTest(CommandFlags cmd_flags, TileIndex, Backup<CompanyID> &cur_company)
 272 {
 273         /* Always execute server and spectator commands as spectator */
 274         bool exec_as_spectator = (cmd_flags & (CMD_SPECTATOR | CMD_SERVER)) != 0;
 275
 276         /* If the company isn't valid it may only do server command or start a new company!
 277          * The server will ditch any server commands a client sends to it, so effectively
 278          * this guards the server from executing functions for an invalid company. */
 279         if (_game_mode == GM_NORMAL && !exec_as_spectator && !Company::IsValidID(_current_company) && !(_current_company == OWNER_DEITY && (cmd_flags & CMD_DEITY) != 0)) {
 280                 return false;
 281         }
 282
 283         if (exec_as_spectator) cur_company.Change(COMPANY_SPECTATOR);
 284
 285         /* Enter test mode. */
 286         _cleared_object_areas.clear();
 287         SetTownRatingTestMode(true);
 288         BasePersistentStorageArray::SwitchMode(PSM_ENTER_TESTMODE);
 289         return true;
 290 }
 291
 292 /**
 293  * Validate result of test run and prepare for real execution.
 294  * @param cmd_flags Command flags.
 295  * @param[in,out] res Command result of test run, may be modified.
 296  * @param estimate_only Is this just cost estimation?
 297  * @param network_command Does this command come from the network?
 298  * @param[in,out] cur_company Backup of current company at start of command execution.
 299  * @return True if test run can go ahead, false on error.
 300  */
 301 std::tuple<bool, bool, bool> CommandHelperBase::InternalExecuteValidateTestAndPrepExec(CommandCost &res, CommandFlags cmd_flags, bool estimate_only, bool network_command, [[maybe_unused]] Backup<CompanyID> &cur_company)
 302 {
 303         BasePersistentStorageArray::SwitchMode(PSM_LEAVE_TESTMODE);
 304         SetTownRatingTestMode(false);
 305
 306         /* Make sure we're not messing things up here. */
 307         assert((cmd_flags & (CMD_SPECTATOR | CMD_SERVER)) != 0 ? _current_company == COMPANY_SPECTATOR : cur_company.Verify());
 308
 309         /* If the command fails, we're doing an estimate
 310          * or the player does not have enough money
 311          * (unless it's a command where the test and
 312          * execution phase might return different costs)
 313          * we bail out here. */
 314         bool test_and_exec_can_differ = (cmd_flags & CMD_NO_TEST) != 0;
 315         if (res.Failed() || estimate_only || (!test_and_exec_can_differ && !CheckCompanyHasMoney(res))) {
 316                 return { true, !_networking || _generating_world || network_command, false };
 317         }
 318
 319         bool send_net = _networking && !_generating_world && !network_command;
 320
 321         if (!send_net) {
 322                 /* Prepare for command execution. */
 323                 _cleared_object_areas.clear();
 324                 BasePersistentStorageArray::SwitchMode(PSM_ENTER_COMMAND);
 325         }
 326
 327         return { false, _debug_desync_level >= 1, send_net };
 328 }
 329
 330 /**
 331  * Process the result of a command test run and execution run.
 332  * @param cmd Command that was executed.
 333  * @param cmd_flags Command flags.
 334  * @param res_test Command result of test run.
 335  * @param tes_exec Command result of real run.
 336  * @param extra_cash Additional cash required for successful command execution.
 337  * @param tile Tile of command execution.
 338  * @param[in,out] cur_company Backup of current company at start of command execution.
 339  * @return Final command result.
 340  */
 341 CommandCost CommandHelperBase::InternalExecuteProcessResult(Commands cmd, CommandFlags cmd_flags, [[maybe_unused]] const CommandCost &res_test, const CommandCost &res_exec, Money extra_cash, TileIndex tile, Backup<CompanyID> &cur_company)
 342 {
 343         BasePersistentStorageArray::SwitchMode(PSM_LEAVE_COMMAND);
 344
 345         if (cmd == CMD_COMPANY_CTRL) {
 346                 cur_company.Trash();
 347                 /* We are a new company                  -> Switch to new local company.
 348                  * We were closed down                   -> Switch to spectator
 349                  * Some other company opened/closed down -> The outside function will switch back */
 350                 _current_company = _local_company;
 351         } else {
 352                 /* Make sure nothing bad happened, like changing the current company. */
 353                 assert((cmd_flags & (CMD_SPECTATOR | CMD_SERVER)) != 0 ? _current_company == COMPANY_SPECTATOR : cur_company.Verify());
 354                 cur_company.Restore();
 355         }
 356
 357         /* If the test and execution can differ we have to check the
 358          * return of the command. Otherwise we can check whether the
 359          * test and execution have yielded the same result,
 360          * i.e. cost and error state are the same. */
 361         bool test_and_exec_can_differ = (cmd_flags & CMD_NO_TEST) != 0;
 362         if (!test_and_exec_can_differ) {
 363                 assert(res_test.GetCost() == res_exec.GetCost() && res_test.Failed() == res_exec.Failed()); // sanity check
 364         } else if (res_exec.Failed()) {
 365                 return res_exec;
 366         }
 367
 368         /* If we're needing more money and we haven't done
 369          * anything yet, ask for the money! */
 370         if (extra_cash != 0 && res_exec.GetCost() == 0) {
 371                 /* It could happen we removed rail, thus gained money, and deleted something else.
 372                  * So make sure the signal buffer is empty even in this case */
 373                 UpdateSignalsInBuffer();
 374                 SetDParam(0, extra_cash);
 375                 return CommandCost(STR_ERROR_NOT_ENOUGH_CASH_REQUIRES_CURRENCY);
 376         }
 377
 378         /* update last build coordinate of company. */
 379         if (tile != 0) {
 380                 Company *c = Company::GetIfValid(_current_company);
 381                 if (c != nullptr) c->last_build_coordinate = tile;
 382         }
 383
 384         SubtractMoneyFromCompany(res_exec);
 385
 386         /* Record if there was a command issues during pause; ignore pause/other setting related changes. */
 387         if (_pause_mode != PM_UNPAUSED && _command_proc_table[cmd].type != CMDT_SERVER_SETTING) _pause_mode |= PM_COMMAND_DURING_PAUSE;
 388
 389         /* update signals if needed */
 390         UpdateSignalsInBuffer();
 391
 392         return res_exec;
 393 }
 394
 395
 396 /**
 397  * Adds the cost of the given command return value to this cost.
 398  * Also takes a possible error message when it is set.
 399  * @param ret The command to add the cost of.
 400  */
 401 void CommandCost::AddCost(const CommandCost &ret)
 402 {
 403         this->AddCost(ret.cost);
 404         if (this->success && !ret.success) {
 405                 this->message = ret.message;
 406                 this->success = false;
 407         }
 408 }
 409
 410 /**
 411  * Values to put on the #TextRefStack for the error message.
 412  * There is only one static instance of the array, just like there is only one
 413  * instance of normal DParams.
 414  */
 415 uint32_t CommandCost::textref_stack[16];
 416
 417 /**
 418  * Activate usage of the NewGRF #TextRefStack for the error message.
 419  * @param grffile NewGRF that provides the #TextRefStack
 420  * @param num_registers number of entries to copy from the temporary NewGRF registers
 421  */
 422 void CommandCost::UseTextRefStack(const GRFFile *grffile, uint num_registers)
 423 {
 424         extern TemporaryStorageArray<int32_t, 0x110> _temp_store;
 425
 426         assert(num_registers < lengthof(textref_stack));
 427         this->textref_stack_grffile = grffile;
 428         this->textref_stack_size = num_registers;
 429         for (uint i = 0; i < num_registers; i++) {
 430                 textref_stack[i] = _temp_store.GetValue(0x100 + i);
 431         }
 432 }