2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
39 #include "ucioption.h"
44 //// Local definitions:
49 // FEN string for the initial position
50 const string StartPositionFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
52 // UCIInputParser is a class for parsing UCI input. The class
53 // is actually a string stream built on a given input string.
55 typedef istringstream UCIInputParser;
57 // The root position. This is set up when the user (or in practice, the GUI)
58 // sends the "position" UCI command. The root position is sent to the think()
59 // function when the program receives the "go" command.
60 Position RootPosition(0);
63 bool handle_command(const string& command);
64 void set_option(UCIInputParser& uip);
65 void set_position(UCIInputParser& uip);
66 bool go(UCIInputParser& uip);
67 void perft(UCIInputParser& uip);
75 /// uci_main_loop() is the only global function in this file. It is
76 /// called immediately after the program has finished initializing.
77 /// The program remains in this loop until it receives the "quit" UCI
78 /// command. It waits for a command from the user, and passes this
79 /// command to handle_command and also intercepts EOF from stdin,
80 /// by translating EOF to the "quit" command. This ensures that Stockfish
81 /// exits gracefully if the GUI dies unexpectedly.
83 void uci_main_loop() {
85 RootPosition.from_fen(StartPositionFEN);
89 // Wait for a command from stdin
90 if (!getline(cin, command))
93 } while (handle_command(command));
103 // handle_command() takes a text string as input, uses a
104 // UCIInputParser object to parse this text string as a UCI command,
105 // and calls the appropriate functions. In addition to the UCI
106 // commands, the function also supports a few debug commands.
108 bool handle_command(const string& command) {
110 UCIInputParser uip(command);
113 if (!(uip >> token)) // operator>>() skips any whitespace
124 cout << "id name " << engine_name()
125 << "\nid author Tord Romstad, Marco Costalba, Joona Kiiski\n";
127 cout << "uciok" << endl;
129 else if (token == "ucinewgame")
131 push_button("New Game");
132 RootPosition.from_fen(StartPositionFEN);
134 else if (token == "isready")
135 cout << "readyok" << endl;
136 else if (token == "position")
138 else if (token == "setoption")
141 // The remaining commands are for debugging purposes only.
142 // Perhaps they should be removed later in order to reduce the
143 // size of the program binary.
144 else if (token == "d")
145 RootPosition.print();
146 else if (token == "flip")
148 Position p(RootPosition, RootPosition.thread());
149 RootPosition.flipped_copy(p);
151 else if (token == "eval")
154 cout << "Incremental mg: " << mg_value(RootPosition.value())
155 << "\nIncremental eg: " << eg_value(RootPosition.value())
156 << "\nFull eval: " << evaluate(RootPosition, evalMargin) << endl;
158 else if (token == "key")
159 cout << "key: " << hex << RootPosition.get_key()
160 << "\nmaterial key: " << RootPosition.get_material_key()
161 << "\npawn key: " << RootPosition.get_pawn_key() << endl;
162 else if (token == "perft")
165 cout << "Unknown command: " << command << endl;
171 // set_position() is called when Stockfish receives the "position" UCI
172 // command. The input parameter is a UCIInputParser. It is assumed
173 // that this parser has consumed the first token of the UCI command
174 // ("position"), and is ready to read the second token ("startpos"
175 // or "fen", if the input is well-formed).
177 void set_position(UCIInputParser& uip) {
181 if (!(uip >> token)) // operator>>() skips any whitespace
184 if (token == "startpos")
185 RootPosition.from_fen(StartPositionFEN);
186 else if (token == "fen")
189 while (uip >> token && token != "moves")
194 RootPosition.from_fen(fen);
199 if (token != "moves")
202 if (token == "moves")
208 move = move_from_string(RootPosition, token);
209 RootPosition.do_move(move, st);
210 if (RootPosition.rule_50_counter() == 0)
211 RootPosition.reset_game_ply();
213 RootPosition.inc_startpos_ply_counter(); //FIXME: make from_fen to support this and rule50
215 // Our StateInfo st is about going out of scope so copy
216 // its content inside RootPosition before it disappears.
217 RootPosition.detach();
223 // set_option() is called when Stockfish receives the "setoption" UCI
224 // command. The input parameter is a UCIInputParser. It is assumed
225 // that this parser has consumed the first token of the UCI command
226 // ("setoption"), and is ready to read the second token ("name", if
227 // the input is well-formed).
229 void set_option(UCIInputParser& uip) {
231 string token, name, value;
233 if (!(uip >> token)) // operator>>() skips any whitespace
236 if (token == "name" && uip >> name)
238 while (uip >> token && token != "value")
239 name += (" " + token);
241 if (token == "value" && uip >> value)
244 value += (" " + token);
246 set_option_value(name, value);
253 // go() is called when Stockfish receives the "go" UCI command. The
254 // input parameter is a UCIInputParser. It is assumed that this
255 // parser has consumed the first token of the UCI command ("go"),
256 // and is ready to read the second token. The function sets the
257 // thinking time and other parameters from the input string, and
258 // calls think() (defined in search.cpp) with the appropriate
259 // parameters. Returns false if a quit command is received while
260 // thinking, returns true otherwise.
262 bool go(UCIInputParser& uip) {
266 int time[2] = {0, 0}, inc[2] = {0, 0};
267 int movesToGo = 0, depth = 0, nodes = 0, moveTime = 0;
268 bool infinite = false, ponder = false;
269 Move searchMoves[500];
271 searchMoves[0] = MOVE_NONE;
275 if (token == "infinite")
277 else if (token == "ponder")
279 else if (token == "wtime")
281 else if (token == "btime")
283 else if (token == "winc")
285 else if (token == "binc")
287 else if (token == "movestogo")
289 else if (token == "depth")
291 else if (token == "nodes")
293 else if (token == "movetime")
295 else if (token == "searchmoves")
299 searchMoves[numOfMoves++] = move_from_string(RootPosition, token);
301 searchMoves[numOfMoves] = MOVE_NONE;
305 assert(RootPosition.is_ok());
307 return think(RootPosition, infinite, ponder, time, inc, movesToGo,
308 depth, nodes, moveTime, searchMoves);
311 void perft(UCIInputParser& uip) {
315 Position pos(RootPosition, RootPosition.thread());
320 tm = get_system_time();
322 n = perft(pos, depth * ONE_PLY);
324 tm = get_system_time() - tm;
325 std::cout << "\nNodes " << n
326 << "\nTime (ms) " << tm
327 << "\nNodes/second " << (int)(n/(tm/1000.0)) << std::endl;