/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
-////
-//// Includes
-////
-
-#include <cassert>
-#include <cctype>
#include <iostream>
#include <sstream>
#include <string>
#include "evaluate.h"
-#include "misc.h"
-#include "move.h"
#include "movegen.h"
#include "position.h"
-#include "san.h"
#include "search.h"
-#include "ucioption.h"
+#include "thread.h"
+#include "tt.h"
+#include "uci.h"
using namespace std;
+extern void benchmark(const Position& pos, istream& is);
namespace {
- // FEN string for the initial position
- const string StartPositionFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
-
- // UCIParser is a class for parsing UCI input. The class
- // is actually a string stream built on a given input string.
- typedef istringstream UCIParser;
-
- // Local functions
- void set_option(UCIParser& up);
- void set_position(Position& pos, UCIParser& up);
- bool go(Position& pos, UCIParser& up);
- void perft(Position& pos, UCIParser& up);
- Move parse_uci_move(const Position& pos, const std::string &str);
-}
+ // FEN string of the initial position, normal chess
+ const char* StartFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
+ // Stack to keep track of the position states along the setup moves (from the
+ // start position to the position just before the search starts). Needed by
+ // 'draw by repetition' detection.
+ Search::StateStackPtr SetupStates;
-/// execute_uci_command() takes a string as input, uses a UCIParser
-/// object to parse this text string as a UCI command, and calls
-/// the appropriate functions. In addition to the UCI commands,
-/// the function also supports a few debug commands.
-bool execute_uci_command(const string& cmd) {
+ // position() is called when engine receives the "position" UCI command.
+ // The function sets up the position described in the given FEN string ("fen")
+ // or the starting position ("startpos") and then makes the moves given in the
+ // following move list ("moves").
- static Position pos(StartPositionFEN, false, 0); // The root position
- UCIParser up(cmd);
- string token;
+ void position(Position& pos, istringstream& is) {
- if (!(up >> token)) // operator>>() skips any whitespace
- return true;
-
- if (token == "quit")
- return false;
-
- if (token == "go")
- return go(pos, up);
-
- if (token == "uci")
- {
- cout << "id name " << engine_name()
- << "\nid author Tord Romstad, Marco Costalba, Joona Kiiski\n";
- print_uci_options();
- cout << "uciok" << endl;
- }
- else if (token == "ucinewgame")
- pos.from_fen(StartPositionFEN, false);
+ Move m;
+ string token, fen;
- else if (token == "isready")
- cout << "readyok" << endl;
+ is >> token;
- else if (token == "position")
- set_position(pos, up);
-
- else if (token == "setoption")
- set_option(up);
+ if (token == "startpos")
+ {
+ fen = StartFEN;
+ is >> token; // Consume "moves" token if any
+ }
+ else if (token == "fen")
+ while (is >> token && token != "moves")
+ fen += token + " ";
+ else
+ return;
- // The remaining commands are for debugging purposes only
- else if (token == "d")
- pos.print();
+ pos.set(fen, Options["UCI_Chess960"], Threads.main());
+ SetupStates = Search::StateStackPtr(new std::stack<StateInfo>());
- else if (token == "flip")
- {
- Position p(pos, pos.thread());
- pos.flipped_copy(p);
- }
- else if (token == "eval")
- {
- Value evalMargin;
- cout << "Incremental mg: " << mg_value(pos.value())
- << "\nIncremental eg: " << eg_value(pos.value())
- << "\nFull eval: " << evaluate(pos, evalMargin) << endl;
+ // Parse move list (if any)
+ while (is >> token && (m = UCI::to_move(pos, token)) != MOVE_NONE)
+ {
+ SetupStates->push(StateInfo());
+ pos.do_move(m, SetupStates->top());
+ }
}
- else if (token == "key")
- cout << "key: " << hex << pos.get_key()
- << "\nmaterial key: " << pos.get_material_key()
- << "\npawn key: " << pos.get_pawn_key() << endl;
- else if (token == "perft")
- perft(pos, up);
- else
- cout << "Unknown command: " << cmd << endl;
-
- return true;
-}
-
-
-////
-//// Local functions
-////
-
-namespace {
-
- // parse_uci_move() takes a position and a string as input, and attempts to
- // convert the string to a move, using simple coordinate notation (g1f3,
- // a7a8q, etc.). In order to correctly parse en passant captures and castling
- // moves, we need the position. This function is not robust, and expects that
- // the input move is legal and correctly formatted.
-
- Move parse_uci_move(const Position& pos, const std::string& str) {
+ // setoption() is called when engine receives the "setoption" UCI command. The
+ // function updates the UCI option ("name") to the given value ("value").
- Square from, to;
- Piece piece;
- Color us = pos.side_to_move();
+ void setoption(istringstream& is) {
- if (str.length() < 4)
- return MOVE_NONE;
-
- // Read the from and to squares
- from = make_square(file_from_char(str[0]), rank_from_char(str[1]));
- to = make_square(file_from_char(str[2]), rank_from_char(str[3]));
-
- // Find the moving piece
- piece = pos.piece_on(from);
+ string token, name, value;
- // If the string has more than 4 characters, try to interpret the 5th
- // character as a promotion.
- if (str.length() > 4 && piece == piece_of_color_and_type(us, PAWN))
- {
- switch (tolower(str[4])) {
- case 'n':
- return make_promotion_move(from, to, KNIGHT);
- case 'b':
- return make_promotion_move(from, to, BISHOP);
- case 'r':
- return make_promotion_move(from, to, ROOK);
- case 'q':
- return make_promotion_move(from, to, QUEEN);
- }
- }
+ is >> token; // Consume "name" token
- // En passant move? We assume that a pawn move is an en passant move
- // if the destination square is epSquare.
- if (to == pos.ep_square() && piece == piece_of_color_and_type(us, PAWN))
- return make_ep_move(from, to);
+ // Read option name (can contain spaces)
+ while (is >> token && token != "value")
+ name += string(" ", !name.empty()) + token;
- // Is this a castling move? A king move is assumed to be a castling move
- // if the destination square is occupied by a friendly rook, or if the
- // distance between the source and destination squares is more than 1.
- if (piece == piece_of_color_and_type(us, KING))
- {
- if (pos.piece_on(to) == piece_of_color_and_type(us, ROOK))
- return make_castle_move(from, to);
-
- if (square_distance(from, to) > 1)
- {
- // This is a castling move, but we have to translate it to the
- // internal "king captures rook" representation.
- SquareDelta delta = (to > from ? DELTA_E : DELTA_W);
- Square s = from;
-
- do s += delta;
- while ( pos.piece_on(s) != piece_of_color_and_type(us, ROOK)
- && relative_rank(us, s) == RANK_1);
-
- return relative_rank(us, s) == RANK_1 ? make_castle_move(from, s) : MOVE_NONE;
- }
- }
+ // Read option value (can contain spaces)
+ while (is >> token)
+ value += string(" ", !value.empty()) + token;
- return make_move(from, to);
+ if (Options.count(name))
+ Options[name] = value;
+ else
+ sync_cout << "No such option: " << name << sync_endl;
}
- // set_position() is called when Stockfish receives the "position" UCI
- // command. The input parameter is a UCIParser. It is assumed
- // that this parser has consumed the first token of the UCI command
- // ("position"), and is ready to read the second token ("startpos"
- // or "fen", if the input is well-formed).
-
- void set_position(Position& pos, UCIParser& up) {
- string token;
+ // go() is called when engine receives the "go" UCI command. The function sets
+ // the thinking time and other parameters from the input string, then starts
+ // the search.
- if (!(up >> token) || (token != "startpos" && token != "fen"))
- return;
+ void go(const Position& pos, istringstream& is) {
- if (token == "startpos")
- {
- pos.from_fen(StartPositionFEN, false);
- if (!(up >> token))
- return;
- }
- else // fen
- {
- string fen;
- while (up >> token && token != "moves")
- {
- fen += token;
- fen += ' ';
- }
- pos.from_fen(fen, Options["UCI_Chess960"].value<bool>());
- }
-
- if (token != "moves")
- return;
+ Search::LimitsType limits;
+ string token;
- // Parse optional move list
- Move move;
- StateInfo st;
- while (up >> token)
- {
- move = parse_uci_move(pos, token);
- pos.do_setup_move(move, st);
- }
- // Our StateInfo st is about going out of scope so copy
- // its content inside pos before it disappears.
- pos.detach();
+ while (is >> token)
+ if (token == "searchmoves")
+ while (is >> token)
+ limits.searchmoves.push_back(UCI::to_move(pos, token));
+
+ else if (token == "wtime") is >> limits.time[WHITE];
+ else if (token == "btime") is >> limits.time[BLACK];
+ else if (token == "winc") is >> limits.inc[WHITE];
+ else if (token == "binc") is >> limits.inc[BLACK];
+ else if (token == "movestogo") is >> limits.movestogo;
+ else if (token == "depth") is >> limits.depth;
+ else if (token == "nodes") is >> limits.nodes;
+ else if (token == "movetime") is >> limits.movetime;
+ else if (token == "mate") is >> limits.mate;
+ else if (token == "infinite") limits.infinite = true;
+ else if (token == "ponder") limits.ponder = true;
+
+ Threads.start_thinking(pos, limits, SetupStates);
}
+} // namespace
+
+
+/// UCI::loop() waits for a command from stdin, parses it and calls the appropriate
+/// function. Also intercepts EOF from stdin to ensure gracefully exiting if the
+/// GUI dies unexpectedly. When called with some command line arguments, e.g. to
+/// run 'bench', once the command is executed the function returns immediately.
+/// In addition to the UCI ones, also some additional debug commands are supported.
+
+void UCI::loop(int argc, char* argv[]) {
+
+ Position pos(StartFEN, false, Threads.main()); // The root position
+ string token, cmd;
+
+ for (int i = 1; i < argc; ++i)
+ cmd += std::string(argv[i]) + " ";
+
+ do {
+ if (argc == 1 && !getline(cin, cmd)) // Block here waiting for input or EOF
+ cmd = "quit";
+
+ istringstream is(cmd);
+
+ token.clear(); // getline() could return empty or blank line
+ is >> skipws >> token;
+
+ // The GUI sends 'ponderhit' to tell us to ponder on the same move the
+ // opponent has played. In case Signals.stopOnPonderhit is set we are
+ // waiting for 'ponderhit' to stop the search (for instance because we
+ // already ran out of time), otherwise we should continue searching but
+ // switching from pondering to normal search.
+ if ( token == "quit"
+ || token == "stop"
+ || (token == "ponderhit" && Search::Signals.stopOnPonderhit))
+ {
+ Search::Signals.stop = true;
+ Threads.main()->notify_one(); // Could be sleeping
+ }
+ else if (token == "ponderhit")
+ Search::Limits.ponder = false; // Switch to normal search
+
+ else if (token == "uci")
+ sync_cout << "id name " << engine_info(true)
+ << "\n" << Options
+ << "\nuciok" << sync_endl;
+
+ else if (token == "isready") sync_cout << "readyok" << sync_endl;
+ else if (token == "ucinewgame") TT.clear();
+ else if (token == "go") go(pos, is);
+ else if (token == "position") position(pos, is);
+ else if (token == "setoption") setoption(is);
+
+ // Additional custom non-UCI commands, useful for debugging
+ else if (token == "flip") pos.flip();
+ else if (token == "bench") benchmark(pos, is);
+ else if (token == "d") sync_cout << pos << sync_endl;
+ else if (token == "eval") sync_cout << Eval::trace(pos) << sync_endl;
+ else if (token == "perft")
+ {
+ int depth;
+ stringstream ss;
+
+ is >> depth;
+ ss << Options["Hash"] << " "
+ << Options["Threads"] << " " << depth << " current perft";
+
+ benchmark(pos, ss);
+ }
+ else
+ sync_cout << "Unknown command: " << cmd << sync_endl;
+
+ } while (token != "quit" && argc == 1); // Passed args have one-shot behaviour
+
+ Threads.wait_for_think_finished(); // Cannot quit whilst the search is running
+}
- // set_option() is called when Stockfish receives the "setoption" UCI
- // command. The input parameter is a UCIParser. It is assumed
- // that this parser has consumed the first token of the UCI command
- // ("setoption"), and is ready to read the second token ("name", if
- // the input is well-formed).
- void set_option(UCIParser& up) {
+/// UCI::value() converts a Value to a string suitable for use with the UCI
+/// protocol specification:
+///
+/// cp <x> The score from the engine's point of view in centipawns.
+/// mate <y> Mate in y moves, not plies. If the engine is getting mated
+/// use negative values for y.
- string token, name, value;
+string UCI::value(Value v) {
- if (!(up >> token) || token != "name") // operator>>() skips any whitespace
- return;
+ stringstream ss;
- if (!(up >> name))
- return;
+ if (abs(v) < VALUE_MATE - MAX_PLY)
+ ss << "cp " << v * 100 / PawnValueEg;
+ else
+ ss << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
- // Handle names with included spaces
- while (up >> token && token != "value")
- name += (" " + token);
+ return ss.str();
+}
- if (Options.find(name) == Options.end())
- {
- cout << "No such option: " << name << endl;
- return;
- }
- // Is a button ?
- if (token != "value")
- {
- Options[name].set_value("true");
- return;
- }
+/// UCI::square() converts a Square to a string in algebraic notation (g1, a7, etc.)
- if (!(up >> value))
- return;
+std::string UCI::square(Square s) {
- // Handle values with included spaces
- while (up >> token)
- value += (" " + token);
+ char sq[] = { char('a' + file_of(s)), char('1' + rank_of(s)), 0 }; // NULL terminated
+ return sq;
+}
- Options[name].set_value(value);
- }
+/// UCI::move() converts a Move to a string in coordinate notation (g1f3, a7a8q).
+/// The only special case is castling, where we print in the e1g1 notation in
+/// normal chess mode, and in e1h1 notation in chess960 mode. Internally all
+/// castling moves are always encoded as 'king captures rook'.
- // go() is called when Stockfish receives the "go" UCI command. The
- // input parameter is a UCIParser. It is assumed that this
- // parser has consumed the first token of the UCI command ("go"),
- // and is ready to read the second token. The function sets the
- // thinking time and other parameters from the input string, and
- // calls think() (defined in search.cpp) with the appropriate
- // parameters. Returns false if a quit command is received while
- // thinking, returns true otherwise.
+string UCI::move(Move m, bool chess960) {
- bool go(Position& pos, UCIParser& up) {
+ Square from = from_sq(m);
+ Square to = to_sq(m);
- string token;
+ if (m == MOVE_NONE)
+ return "(none)";
- int time[2] = {0, 0}, inc[2] = {0, 0};
- int movesToGo = 0, depth = 0, nodes = 0, moveTime = 0;
- bool infinite = false, ponder = false;
- Move searchMoves[MOVES_MAX];
+ if (m == MOVE_NULL)
+ return "0000";
- searchMoves[0] = MOVE_NONE;
+ if (type_of(m) == CASTLING && !chess960)
+ to = make_square(to > from ? FILE_G : FILE_C, rank_of(from));
- while (up >> token)
- {
- if (token == "infinite")
- infinite = true;
- else if (token == "ponder")
- ponder = true;
- else if (token == "wtime")
- up >> time[0];
- else if (token == "btime")
- up >> time[1];
- else if (token == "winc")
- up >> inc[0];
- else if (token == "binc")
- up >> inc[1];
- else if (token == "movestogo")
- up >> movesToGo;
- else if (token == "depth")
- up >> depth;
- else if (token == "nodes")
- up >> nodes;
- else if (token == "movetime")
- up >> moveTime;
- else if (token == "searchmoves")
- {
- int numOfMoves = 0;
- while (up >> token)
- searchMoves[numOfMoves++] = parse_uci_move(pos, token);
-
- searchMoves[numOfMoves] = MOVE_NONE;
- }
- }
+ string move = UCI::square(from) + UCI::square(to);
- assert(pos.is_ok());
+ if (type_of(m) == PROMOTION)
+ move += " pnbrqk"[promotion_type(m)];
- return think(pos, infinite, ponder, time, inc, movesToGo,
- depth, nodes, moveTime, searchMoves);
- }
+ return move;
+}
- void perft(Position& pos, UCIParser& up) {
- int depth, tm;
- int64_t n;
+/// UCI::to_move() converts a string representing a move in coordinate notation
+/// (g1f3, a7a8q) to the corresponding legal Move, if any.
- if (!(up >> depth))
- return;
+Move UCI::to_move(const Position& pos, string& str) {
- tm = get_system_time();
+ if (str.length() == 5) // Junior could send promotion piece in uppercase
+ str[4] = char(tolower(str[4]));
- n = perft(pos, depth * ONE_PLY);
+ for (MoveList<LEGAL> it(pos); *it; ++it)
+ if (str == UCI::move(*it, pos.is_chess960()))
+ return *it;
- tm = get_system_time() - tm;
- std::cout << "\nNodes " << n
- << "\nTime (ms) " << tm
- << "\nNodes/second " << int(n / (tm / 1000.0)) << std::endl;
- }
+ return MOVE_NONE;
}