////
#include <cassert>
+#include <cctype>
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
-////
-//// Local definitions:
-////
namespace {
typedef istringstream UCIParser;
// Local functions
- bool handle_command(Position& pos, const string& command);
- void set_option(UCIParser& uip);
- void set_position(Position& pos, UCIParser& uip);
- bool go(Position& pos, UCIParser& uip);
- void perft(Position& pos, UCIParser& uip);
+ 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);
}
-////
-//// Functions
-////
+/// 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) {
+
+ static Position pos(StartPositionFEN, false, 0); // The root position
+ UCIParser up(cmd);
+ string token;
+
+ if (!(up >> token)) // operator>>() skips any whitespace
+ return true;
+
+ if (token == "quit")
+ return false;
+
+ if (token == "go")
+ return go(pos, up);
-/// 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.
+ 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);
+
+ else if (token == "isready")
+ cout << "readyok" << endl;
+
+ else if (token == "position")
+ set_position(pos, up);
-void uci_main_loop() {
+ else if (token == "setoption")
+ set_option(up);
- Position pos(StartPositionFEN, 0); // The root position
- string command;
+ // The remaining commands are for debugging purposes only
+ else if (token == "d")
+ pos.print();
- do {
- // Wait for a command from stdin
- if (!getline(cin, command))
- command = "quit";
+ 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;
- } while (handle_command(pos, command));
+ else if (token == "perft")
+ perft(pos, up);
+
+ else
+ cout << "Unknown command: " << cmd << endl;
+
+ return true;
}
namespace {
- // handle_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.
+ // 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.
- bool handle_command(Position& pos, const string& command) {
+ Move parse_uci_move(const Position& pos, const std::string& str) {
- UCIParser up(command);
- string token;
+ Square from, to;
+ Piece piece;
+ Color us = pos.side_to_move();
- if (!(up >> token)) // operator>>() skips any whitespace
- return true;
+ if (str.length() < 4)
+ return MOVE_NONE;
- if (token == "quit")
- return false;
+ // 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]));
- if (token == "go")
- return go(pos, up);
+ // Find the moving piece
+ piece = pos.piece_on(from);
- if (token == "uci")
+ // 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))
{
- cout << "id name " << engine_name()
- << "\nid author Tord Romstad, Marco Costalba, Joona Kiiski\n";
- print_uci_options();
- cout << "uciok" << endl;
+ 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);
+ }
}
- else if (token == "ucinewgame")
- pos.from_fen(StartPositionFEN);
- else if (token == "isready")
- cout << "readyok" << endl;
+ // 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 == "position")
- set_position(pos, up);
+ // 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);
- else if (token == "setoption")
- set_option(up);
+ 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;
- // The remaining commands are for debugging purposes only
- else if (token == "d")
- pos.print();
+ do s += delta;
+ while ( pos.piece_on(s) != piece_of_color_and_type(us, ROOK)
+ && relative_rank(us, s) == RANK_1);
- 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;
+ return relative_rank(us, s) == RANK_1 ? make_castle_move(from, s) : MOVE_NONE;
+ }
}
- 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: " << command << endl;
-
- return true;
+ return make_move(from, to);
}
-
// 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
string token;
- if (!(up >> token)) // operator>>() skips any whitespace
+ if (!(up >> token) || (token != "startpos" && token != "fen"))
return;
if (token == "startpos")
- pos.from_fen(StartPositionFEN);
- else if (token == "fen")
+ {
+ 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);
+ pos.from_fen(fen, Options["UCI_Chess960"].value<bool>());
}
- if (up.good())
- {
- if (token != "moves")
- up >> token;
+ if (token != "moves")
+ return;
- if (token == "moves")
- {
- Move move;
- StateInfo st;
- while (up >> token)
- {
- move = move_from_uci(pos, token);
- pos.do_move(move, st);
- if (pos.rule_50_counter() == 0)
- pos.reset_game_ply();
-
- pos.inc_startpos_ply_counter(); //FIXME: make from_fen to support this and rule50
- }
- // Our StateInfo st is about going out of scope so copy
- // its content inside pos before it disappears.
- pos.detach();
- }
+ // 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();
}
{
int numOfMoves = 0;
while (up >> token)
- searchMoves[numOfMoves++] = move_from_uci(pos, token);
+ searchMoves[numOfMoves++] = parse_uci_move(pos, token);
searchMoves[numOfMoves] = MOVE_NONE;
}
void perft(Position& pos, UCIParser& up) {
- int depth, tm, n;
+ int depth, tm;
+ int64_t n;
if (!(up >> depth))
return;