along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
-////
-//// Includes
-////
-
-#include <cassert>
-#include <cctype>
#include <iostream>
#include <sstream>
#include <string>
+#include <vector>
#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 "ucioption.h"
using namespace std;
-
namespace {
- // FEN string for the initial position
- const string StartPositionFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
+ // FEN string of the initial position, normal chess
+ const char* StartFEN = "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;
+ // Keep track of position keys along the setup moves (from start position to the
+ // position just before to start searching). This is needed by draw detection
+ // where, due to 50 moves rule, we need to check at most 100 plies back.
+ StateInfo StateRingBuf[102], *SetupState = StateRingBuf;
- // 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);
+ void set_option(istringstream& up);
+ void set_position(Position& pos, istringstream& up);
+ void go(Position& pos, istringstream& up);
+ void perft(Position& pos, istringstream& up);
}
-/// 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) {
+/// Wait for a command from the user, parse this text string as an UCI command,
+/// and call the appropriate functions. Also intercepts EOF from stdin to ensure
+/// that we exit gracefully if the GUI dies unexpectedly. In addition to the UCI
+/// commands, the function also supports a few debug commands.
- static Position pos(StartPositionFEN, false, 0); // The root position
- UCIParser up(cmd);
- string token;
+void uci_loop() {
- if (!(up >> token)) // operator>>() skips any whitespace
- return true;
+ Position pos(StartFEN, false, 0); // The root position
+ string cmd, token;
- if (token == "quit")
- return false;
-
- if (token == "go")
- return go(pos, up);
-
- if (token == "uci")
+ while (token != "quit")
{
- 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);
+ if (!getline(cin, cmd)) // Block here waiting for input
+ cmd = "quit";
- else if (token == "isready")
- cout << "readyok" << endl;
+ istringstream is(cmd);
- else if (token == "position")
- set_position(pos, up);
+ is >> skipws >> token;
- else if (token == "setoption")
- set_option(up);
+ if (token == "quit" || token == "stop")
+ {
+ Search::Signals.stop = true;
+ Threads[0].wake_up(); // In case is waiting for stop or ponderhit
+ }
- // The remaining commands are for debugging purposes only
- else if (token == "d")
- pos.print();
+ else if (token == "ponderhit")
+ {
+ // The opponent has played the expected move. GUI sends "ponderhit" if
+ // we were told to ponder on the same move the opponent has played. We
+ // should continue searching but switching from pondering to normal search.
+ Search::Limits.ponder = false;
- 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;
- }
- else if (token == "key")
- cout << "key: " << hex << pos.get_key()
- << "\nmaterial key: " << pos.get_material_key()
- << "\npawn key: " << pos.get_pawn_key() << endl;
+ if (Search::Signals.stopOnPonderhit)
+ Search::Signals.stop = true;
- else if (token == "perft")
- perft(pos, up);
+ Threads[0].wake_up(); // In case is waiting for stop or ponderhit
+ }
- else
- cout << "Unknown command: " << cmd << endl;
+ else if (token == "go")
+ go(pos, is);
- return true;
-}
+ else if (token == "ucinewgame")
+ pos.from_fen(StartFEN, false);
+ else if (token == "isready")
+ cout << "readyok" << endl;
-////
-//// Local functions
-////
+ else if (token == "position")
+ set_position(pos, is);
-namespace {
+ else if (token == "setoption")
+ set_option(is);
- // 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.
+ else if (token == "perft")
+ perft(pos, is);
- Move parse_uci_move(const Position& pos, const std::string& str) {
+ else if (token == "d")
+ pos.print();
- Square from, to;
- Piece piece;
- Color us = pos.side_to_move();
+ else if (token == "flip")
+ pos.flip_me();
- if (str.length() < 4)
- return MOVE_NONE;
+ else if (token == "eval")
+ {
+ read_evaluation_uci_options(pos.side_to_move());
+ cout << trace_evaluate(pos) << endl;
+ }
- // 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]));
+ else if (token == "key")
+ cout << "key: " << hex << pos.get_key()
+ << "\nmaterial key: " << pos.get_material_key()
+ << "\npawn key: " << pos.get_pawn_key() << endl;
- // Find the moving piece
- piece = pos.piece_on(from);
-
- // 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);
- }
- }
-
- // 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);
+ else if (token == "uci")
+ cout << "id name " << engine_name()
+ << "\nid author " << engine_authors()
+ << "\n" << Options.print_all()
+ << "\nuciok" << endl;
+ else
+ cout << "Unknown command: " << cmd << endl;
+ }
+}
- // 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;
- }
- }
- return make_move(from, to);
- }
+namespace {
- // 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).
+ // set_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 set_position(Position& pos, UCIParser& up) {
+ void set_position(Position& pos, istringstream& is) {
- string token;
+ Move m;
+ string token, fen;
- if (!(up >> token) || (token != "startpos" && token != "fen"))
- return;
+ is >> token;
if (token == "startpos")
{
- pos.from_fen(StartPositionFEN, false);
- if (!(up >> token))
- return;
+ fen = StartFEN;
+ is >> token; // Consume "moves" token if any
}
- else // fen
- {
- string fen;
- while (up >> token && token != "moves")
- {
- fen += token;
- fen += ' ';
- }
- pos.from_fen(fen, Options["UCI_Chess960"].value<bool>());
- }
-
- if (token != "moves")
+ else if (token == "fen")
+ while (is >> token && token != "moves")
+ fen += token + " ";
+ else
return;
- // Parse optional move list
- Move move;
- StateInfo st;
- while (up >> token)
+ pos.from_fen(fen, Options["UCI_Chess960"].value<bool>());
+
+ // Parse move list (if any)
+ while (is >> token && (m = move_from_uci(pos, token)) != MOVE_NONE)
{
- move = parse_uci_move(pos, token);
- pos.do_setup_move(move, st);
+ pos.do_move(m, *SetupState);
+
+ // Increment pointer to StateRingBuf circular buffer
+ if (++SetupState - StateRingBuf >= 102)
+ SetupState = StateRingBuf;
}
- // Our StateInfo st is about going out of scope so copy
- // its content inside pos before it disappears.
- pos.detach();
}
- // 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).
+ // set_option() is called when engine receives the "setoption" UCI command. The
+ // function updates the UCI option ("name") to the given value ("value").
- void set_option(UCIParser& up) {
+ void set_option(istringstream& is) {
string token, name, value;
- if (!(up >> token) || token != "name") // operator>>() skips any whitespace
- return;
+ is >> token; // Consume "name" token
- if (!(up >> name))
- return;
+ // Read option name (can contain spaces)
+ while (is >> token && token != "value")
+ name += string(" ", !name.empty()) + token;
- // Handle names with included spaces
- while (up >> token && token != "value")
- name += (" " + token);
+ // Read option value (can contain spaces)
+ while (is >> token)
+ value += string(" ", !value.empty()) + token;
- if (Options.find(name) == Options.end())
- {
+ if (Options.find(name) != Options.end())
+ Options[name].set_value(value.empty() ? "true" : value); // UCI buttons don't have "value"
+ else
cout << "No such option: " << name << endl;
- return;
- }
-
- // Is a button ?
- if (token != "value")
- {
- Options[name].set_value("true");
- return;
- }
-
- if (!(up >> value))
- return;
-
- // Handle values with included spaces
- while (up >> token)
- value += (" " + token);
-
- Options[name].set_value(value);
}
- // 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.
+ // go() is called when engine receives the "go" UCI command. The function sets
+ // the thinking time and other parameters from the input string, and then starts
+ // the main searching thread.
- bool go(Position& pos, UCIParser& up) {
+ void go(Position& pos, istringstream& is) {
string token;
+ Search::LimitsType limits;
+ std::vector<Move> searchMoves;
+ int time[] = { 0, 0 }, inc[] = { 0, 0 };
- 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];
-
- searchMoves[0] = MOVE_NONE;
-
- while (up >> token)
+ while (is >> token)
{
if (token == "infinite")
- infinite = true;
+ limits.infinite = true;
else if (token == "ponder")
- ponder = true;
+ limits.ponder = true;
else if (token == "wtime")
- up >> time[0];
+ is >> time[WHITE];
else if (token == "btime")
- up >> time[1];
+ is >> time[BLACK];
else if (token == "winc")
- up >> inc[0];
+ is >> inc[WHITE];
else if (token == "binc")
- up >> inc[1];
+ is >> inc[BLACK];
else if (token == "movestogo")
- up >> movesToGo;
+ is >> limits.movesToGo;
else if (token == "depth")
- up >> depth;
+ is >> limits.maxDepth;
else if (token == "nodes")
- up >> nodes;
+ is >> limits.maxNodes;
else if (token == "movetime")
- up >> moveTime;
+ is >> limits.maxTime;
else if (token == "searchmoves")
- {
- int numOfMoves = 0;
- while (up >> token)
- searchMoves[numOfMoves++] = parse_uci_move(pos, token);
-
- searchMoves[numOfMoves] = MOVE_NONE;
- }
+ while (is >> token)
+ searchMoves.push_back(move_from_uci(pos, token));
}
- assert(pos.is_ok());
+ searchMoves.push_back(MOVE_NONE);
+ limits.time = time[pos.side_to_move()];
+ limits.increment = inc[pos.side_to_move()];
- return think(pos, infinite, ponder, time, inc, movesToGo,
- depth, nodes, moveTime, searchMoves);
+ Threads.start_thinking(pos, limits, searchMoves, true);
}
- void perft(Position& pos, UCIParser& up) {
- int depth, tm;
- int64_t n;
+ // perft() is called when engine receives the "perft" command. The function
+ // calls perft() with the required search depth then prints counted leaf nodes
+ // and elapsed time.
- if (!(up >> depth))
+ void perft(Position& pos, istringstream& is) {
+
+ int depth, time;
+
+ if (!(is >> depth))
return;
- tm = get_system_time();
+ time = get_system_time();
+
+ int64_t n = Search::perft(pos, depth * ONE_PLY);
- n = perft(pos, depth * ONE_PLY);
+ time = get_system_time() - time;
- tm = get_system_time() - tm;
std::cout << "\nNodes " << n
- << "\nTime (ms) " << tm
- << "\nNodes/second " << int(n / (tm / 1000.0)) << std::endl;
+ << "\nTime (ms) " << time
+ << "\nNodes/second " << int(n / (time / 1000.0)) << std::endl;
}
}