/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2009 Marco Costalba
+ 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 <iostream>
#include <sstream>
#include <string>
-#include "book.h"
#include "evaluate.h"
-#include "misc.h"
-#include "move.h"
#include "movegen.h"
#include "position.h"
-#include "san.h"
#include "search.h"
+#include "thread.h"
+#include "timeman.h"
+#include "tt.h"
#include "uci.h"
-#include "ucioption.h"
using namespace std;
-////
-//// Local definitions:
-////
+extern void benchmark(const Position& pos, istream& is);
namespace {
- // UCIInputParser is a class for parsing UCI input. The class
- // is actually a string stream built on a given input string.
+ // FEN string of the initial position, normal chess
+ const char* StartFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
- typedef istringstream UCIInputParser;
+ // 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;
- // The root position. This is set up when the user (or in practice, the GUI)
- // sends the "position" UCI command. The root position is sent to the think()
- // function when the program receives the "go" command.
- Position RootPosition;
- // Local functions
- bool handle_command(const string& command);
- void set_option(UCIInputParser& uip);
- void set_position(UCIInputParser& uip);
- bool go(UCIInputParser& uip);
- void perft(UCIInputParser& uip);
-}
+ // 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").
+ void position(Position& pos, istringstream& is) {
-////
-//// Functions
-////
+ Move m;
+ string token, fen;
-/// uci_main_loop() is the only global function in this file. It is
-/// called immediately after the program has finished initializing.
-/// The program remains in this loop until it receives the "quit" UCI
-/// command. It waits for a command from the user, and passes this
-/// command to handle_command and also intercepts EOF from stdin,
-/// by translating EOF to the "quit" command. This ensures that Stockfish
-/// exits gracefully if the GUI dies unexpectedly.
+ is >> token;
-void uci_main_loop() {
+ 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;
- RootPosition.from_fen(StartPosition);
- string command;
+ pos.set(fen, Options["UCI_Chess960"], Threads.main());
+ SetupStates = Search::StateStackPtr(new std::stack<StateInfo>);
- do {
- // Wait for a command from stdin
- if (!getline(cin, command))
- command = "quit";
+ // 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(), pos.gives_check(m, CheckInfo(pos)));
+ }
+ }
- } while (handle_command(command));
-}
+ // setoption() is called when engine receives the "setoption" UCI command. The
+ // function updates the UCI option ("name") to the given value ("value").
-////
-//// Local functions
-////
+ void setoption(istringstream& is) {
-namespace {
+ string token, name, value;
- // handle_command() takes a text string as input, uses a
- // UCIInputParser 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.
+ is >> token; // Consume "name" token
- bool handle_command(const string& command) {
+ // Read option name (can contain spaces)
+ while (is >> token && token != "value")
+ name += string(" ", !name.empty()) + token;
- UCIInputParser uip(command);
- string token;
+ // Read option value (can contain spaces)
+ while (is >> token)
+ value += string(" ", !value.empty()) + token;
- uip >> token; // operator>>() skips any whitespace
+ if (Options.count(name))
+ Options[name] = value;
+ else
+ sync_cout << "No such option: " << name << sync_endl;
+ }
- if (token == "quit")
- return false;
- if (token == "go")
- return go(uip);
+ // 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 (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")
- {
- push_button("Clear Hash");
- Position::init_piece_square_tables();
- RootPosition.from_fen(StartPosition);
- }
- else if (token == "isready")
- cout << "readyok" << endl;
- else if (token == "position")
- set_position(uip);
- else if (token == "setoption")
- set_option(uip);
-
- // The remaining commands are for debugging purposes only.
- // Perhaps they should be removed later in order to reduce the
- // size of the program binary.
- else if (token == "d")
- RootPosition.print();
- else if (token == "flip")
- {
- Position p(RootPosition);
- RootPosition.flipped_copy(p);
- }
- else if (token == "eval")
- {
- EvalInfo ei;
- cout << "Incremental mg: " << RootPosition.value().mg()
- << "\nIncremental eg: " << RootPosition.value().eg()
- << "\nFull eval: " << evaluate(RootPosition, ei, 0) << endl;
- }
- else if (token == "key")
- cout << "key: " << hex << RootPosition.get_key()
- << "\nmaterial key: " << RootPosition.get_material_key()
- << "\npawn key: " << RootPosition.get_pawn_key() << endl;
- else if (token == "perft")
- perft(uip);
- else
- {
- cout << "Unknown command: " << command << endl;
- while (!uip.eof())
- {
- uip >> token;
- cout << token << endl;
- }
- }
- return true;
+ void go(const Position& pos, istringstream& is) {
+
+ Search::LimitsType limits;
+ string token;
+
+ 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
- // set_position() is called when Stockfish receives the "position" UCI
- // command. The input parameter is a UCIInputParser. 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(UCIInputParser& uip) {
+/// 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.
- string token;
+void UCI::loop(int argc, char* argv[]) {
- uip >> token; // operator>>() skips any whitespace
+ Position pos(StartFEN, false, Threads.main()); // The root position
+ string token, cmd;
- if (token == "startpos")
- RootPosition.from_fen(StartPosition);
- else if (token == "fen")
- {
- string fen;
- while (token != "moves" && !uip.eof())
- {
- uip >> token;
- fen += token;
- fen += ' ';
- }
- RootPosition.from_fen(fen);
- }
+ for (int i = 1; i < argc; ++i)
+ cmd += std::string(argv[i]) + " ";
- if (!uip.eof())
- {
- if (token != "moves")
- uip >> token;
- if (token == "moves")
- {
- Move move;
- StateInfo st;
- while (!uip.eof())
- {
- uip >> token;
- move = move_from_string(RootPosition, token);
- RootPosition.do_move(move, st);
- if (RootPosition.rule_50_counter() == 0)
- RootPosition.reset_game_ply();
- }
- // Our StateInfo st is about going out of scope so copy
- // its content inside RootPosition before they disappear.
- RootPosition.saveState();
- }
- }
- }
+ 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 == "ucinewgame")
+ {
+ TT.clear();
+ Time.availableNodes = 0;
+ }
+ else if (token == "isready") sync_cout << "readyok" << sync_endl;
+ 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.main()->join(); // Cannot quit whilst the search is running
+}
- // set_option() is called when Stockfish receives the "setoption" UCI
- // command. The input parameter is a UCIInputParser. 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).
+/// 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.
- void set_option(UCIInputParser& uip) {
+string UCI::value(Value v) {
- string token, name;
+ stringstream ss;
- uip >> token;
- if (token == "name")
- {
- uip >> name;
- while (!uip.eof())
- {
- uip >> token;
- if (token == "value")
- break;
-
- name += (" " + token);
- }
- if (token == "value")
- {
- // Reads until end of line and left trim white space
- getline(uip, token);
- token.erase(0, token.find_first_not_of(" \n\r\t"));
-
- set_option_value(name, token);
- } else
- push_button(name);
- }
- }
+ 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;
+ return ss.str();
+}
- // go() is called when Stockfish receives the "go" UCI command. The
- // input parameter is a UCIInputParser. 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.
- bool go(UCIInputParser& uip) {
+/// UCI::square() converts a Square to a string in algebraic notation (g1, a7, etc.)
- string token;
+std::string UCI::square(Square s) {
+ return std::string{ char('a' + file_of(s)), char('1' + rank_of(s)) };
+}
- 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[500];
- searchMoves[0] = MOVE_NONE;
+/// 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'.
- while (!uip.eof())
- {
- uip >> token;
-
- if (token == "infinite")
- infinite = true;
- else if (token == "ponder")
- ponder = true;
- else if (token == "wtime")
- uip >> time[0];
- else if (token == "btime")
- uip >> time[1];
- else if (token == "winc")
- uip >> inc[0];
- else if (token == "binc")
- uip >> inc[1];
- else if (token == "movestogo")
- uip >> movesToGo;
- else if (token == "depth")
- uip >> depth;
- else if (token == "nodes")
- uip >> nodes;
- else if (token == "movetime")
- uip >> moveTime;
- else if (token == "searchmoves")
- {
- int numOfMoves = 0;
- while (!uip.eof())
- {
- uip >> token;
- searchMoves[numOfMoves++] = move_from_string(RootPosition, token);
- }
- searchMoves[numOfMoves] = MOVE_NONE;
- }
- }
+string UCI::move(Move m, bool chess960) {
- if (moveTime)
- infinite = true; // HACK
+ Square from = from_sq(m);
+ Square to = to_sq(m);
- assert(RootPosition.is_ok());
+ if (m == MOVE_NONE)
+ return "(none)";
- return think(RootPosition, infinite, ponder, RootPosition.side_to_move(),
- time, inc, movesToGo, depth, nodes, moveTime, searchMoves);
- }
+ if (m == MOVE_NULL)
+ return "0000";
- void perft(UCIInputParser& uip) {
+ if (type_of(m) == CASTLING && !chess960)
+ to = make_square(to > from ? FILE_G : FILE_C, rank_of(from));
- string token;
- int depth = 0;
+ string move = UCI::square(from) + UCI::square(to);
- while (!uip.eof())
- {
- uip >> token;
+ if (type_of(m) == PROMOTION)
+ move += " pnbrqk"[promotion_type(m)];
- if (token == "depth")
- uip >> depth;
- }
- Position pos = RootPosition;
- int tm = get_system_time();
- int n = perft(pos, depth * OnePly);
- tm = get_system_time() - tm;
- std::cout << "\nNodes " << n
- << "\nTime (ms) " << tm
- << "\nNodes/second " << (int)(n/(tm/1000.0)) << std::endl;
- }
+ return move;
+}
+
+
+/// UCI::to_move() converts a string representing a move in coordinate notation
+/// (g1f3, a7a8q) to the corresponding legal Move, if any.
+
+Move UCI::to_move(const Position& pos, string& str) {
+
+ if (str.length() == 5) // Junior could send promotion piece in uppercase
+ str[4] = char(tolower(str[4]));
+
+ for (const auto& m : MoveList<LEGAL>(pos))
+ if (str == UCI::move(m, pos.is_chess960()))
+ return m;
+
+ return MOVE_NONE;
}