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/>.
31 #include "ucioption.h"
37 // FEN string for the initial position
38 const string StartPositionFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
40 // Keep track of position keys along the setup moves (from start position to the
41 // position just before to start searching). This is needed by draw detection.
42 std::vector<StateInfo> SetupState;
44 // UCIParser is a class for parsing UCI input. The class
45 // is actually a string stream built on a given input string.
46 typedef istringstream UCIParser;
48 void set_option(UCIParser& up);
49 void set_position(Position& pos, UCIParser& up);
50 bool go(Position& pos, UCIParser& up);
51 void perft(Position& pos, UCIParser& up);
55 /// execute_uci_command() takes a string as input, uses a UCIParser
56 /// object to parse this text string as a UCI command, and calls
57 /// the appropriate functions. In addition to the UCI commands,
58 /// the function also supports a few debug commands.
60 bool execute_uci_command(const string& cmd) {
62 static Position pos(StartPositionFEN, false, 0); // The root position
67 up >> skipws >> token;
75 if (token == "ucinewgame")
76 pos.from_fen(StartPositionFEN, false);
78 else if (token == "isready")
79 cout << "readyok" << endl;
81 else if (token == "position")
82 set_position(pos, up);
84 else if (token == "setoption")
87 else if (token == "perft")
90 else if (token == "d")
93 else if (token == "flip")
96 else if (token == "eval")
98 read_evaluation_uci_options(pos.side_to_move());
99 cout << trace_evaluate(pos) << endl;
102 else if (token == "key")
103 cout << "key: " << hex << pos.get_key()
104 << "\nmaterial key: " << pos.get_material_key()
105 << "\npawn key: " << pos.get_pawn_key() << endl;
107 else if (token == "uci")
108 cout << "id name " << engine_name()
109 << "\nid author " << engine_authors()
110 << "\n" << Options.print_all()
111 << "\nuciok" << endl;
113 cout << "Unknown command: " << cmd << endl;
121 // set_position() is called when engine receives the "position" UCI
122 // command. The function sets up the position described in the given
123 // fen string ("fen") or the starting position ("startpos") and then
124 // makes the moves given in the following move list ("moves").
126 void set_position(Position& pos, UCIParser& up) {
133 if (token == "startpos")
135 pos.from_fen(StartPositionFEN, false);
136 up >> token; // Consume "moves" token if any
138 else if (token == "fen")
140 while (up >> token && token != "moves")
143 pos.from_fen(fen, Options["UCI_Chess960"].value<bool>());
147 // Parse move list (if any)
150 while (up >> token && (m = move_from_uci(pos, token)) != MOVE_NONE)
152 SetupState.push_back(StateInfo());
153 pos.do_setup_move(m, SetupState.back());
158 // set_option() is called when engine receives the "setoption" UCI
159 // command. The function updates the corresponding UCI option ("name")
160 // to the given value ("value").
162 void set_option(UCIParser& up) {
164 string token, name, value;
166 up >> token; // Consume "name" token
168 // Read option name (can contain spaces)
169 while (up >> token && token != "value")
170 name += string(" ", !name.empty()) + token;
172 // Read option value (can contain spaces)
174 value += string(" ", !value.empty()) + token;
176 if (Options.find(name) != Options.end())
177 Options[name].set_value(value.empty() ? "true" : value); // UCI buttons don't have "value"
179 cout << "No such option: " << name << endl;
183 // go() is called when engine receives the "go" UCI command. The
184 // function sets the thinking time and other parameters from the input
185 // string, and then calls think(). Returns false if a quit command
186 // is received while thinking, true otherwise.
188 bool go(Position& pos, UCIParser& up) {
192 Move searchMoves[MAX_MOVES], *cur = searchMoves;
193 int time[] = { 0, 0 }, inc[] = { 0, 0 };
197 if (token == "infinite")
198 limits.infinite = true;
199 else if (token == "ponder")
200 limits.ponder = true;
201 else if (token == "wtime")
203 else if (token == "btime")
205 else if (token == "winc")
207 else if (token == "binc")
209 else if (token == "movestogo")
210 up >> limits.movesToGo;
211 else if (token == "depth")
212 up >> limits.maxDepth;
213 else if (token == "nodes")
214 up >> limits.maxNodes;
215 else if (token == "movetime")
216 up >> limits.maxTime;
217 else if (token == "searchmoves")
219 *cur++ = move_from_uci(pos, token);
223 limits.time = time[pos.side_to_move()];
224 limits.increment = inc[pos.side_to_move()];
226 return think(pos, limits, searchMoves);
230 // perft() is called when engine receives the "perft" command.
231 // The function calls perft() passing the required search depth
232 // then prints counted leaf nodes and elapsed time.
234 void perft(Position& pos, UCIParser& up) {
242 time = get_system_time();
244 n = perft(pos, depth * ONE_PLY);
246 time = get_system_time() - time;
248 std::cout << "\nNodes " << n
249 << "\nTime (ms) " << time
250 << "\nNodes/second " << int(n / (time / 1000.0)) << std::endl;