/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2014 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/>.
*/
-#include <iomanip>
#include <iostream>
#include <sstream>
#include <string>
// FEN string of the initial position, normal chess
const char* StartFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
- // Keep a track of the position keys along the setup moves (from the start position
- // to the position just before the search starts). This is needed by the repetition
- // draw detection code.
+ // 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;
// go() is called when engine receives the "go" UCI command. The function sets
- // the thinking time and other parameters from the input string, and starts
+ // the thinking time and other parameters from the input string, then starts
// the search.
void go(const Position& pos, istringstream& is) {
string token;
while (is >> token)
- {
if (token == "searchmoves")
while (is >> token)
limits.searchmoves.push_back(UCI::to_move(pos, token));
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
-/// 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.
+/// 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[]) {
cmd += std::string(argv[i]) + " ";
do {
- if (argc == 1 && !getline(cin, cmd)) // Block here waiting for input
+ 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;
- if (token == "quit" || token == "stop" || token == "ponderhit")
+ // 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))
{
- // 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
- // switch from pondering to normal search.
- if (token != "ponderhit" || Search::Signals.stopOnPonderhit)
- {
- Search::Signals.stop = true;
- Threads.main()->notify_one(); // Could be sleeping
- }
- else
- Search::Limits.ponder = false;
- }
- else if (token == "perft")
- {
- int depth;
- stringstream ss;
-
- is >> depth;
- ss << Options["Hash"] << " "
- << Options["Threads"] << " " << depth << " current " << token;
-
- benchmark(pos, ss);
+ Search::Signals.stop = true;
+ Threads.main()->notify_one(); // Could be sleeping
}
- else if (token == "key")
- sync_cout << hex << uppercase << setfill('0')
- << "position key: " << setw(16) << pos.key()
- << "\nmaterial key: " << setw(16) << pos.material_key()
- << "\npawn key: " << setw(16) << pos.pawn_key()
- << dec << nouppercase << setfill(' ') << sync_endl;
+ 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 == "isready") sync_cout << "readyok" << 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;
}
-/// Convert a Value to a string suitable for use with the UCI protocol
-/// specifications:
+/// 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.
+/// 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 UCI::value(Value v, Value alpha, Value beta) {
+string UCI::value(Value v) {
stringstream ss;
else
ss << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
- ss << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : "");
-
return ss.str();
}
-/// Convert a Square to a string in algebraic notation (g1, a7, etc.)
+/// UCI::square() converts a Square to a string in algebraic notation (g1, a7, etc.)
std::string UCI::square(Square s) {
-
- char sq[] = { char('a' + file_of(s)), char('1' + rank_of(s)), 0 };
- return sq;
+ return std::string{ char('a' + file_of(s)), char('1' + rank_of(s)) };
}
-/// Convert a Move to a string in pure coordinate notation (g1f3, a7a8q). The
-/// only special case is castling moves, where we print in the e1g1 notation in
-/// normal chess mode, and in e1h1 notation in chess960 mode. Internally
-/// castling moves are always encoded as "king captures rook".
+/// 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'.
string UCI::move(Move m, bool chess960) {
}
-/// Convert a string representing a move in pure coordinate notation to the
-/// corresponding legal Move, if any.
+/// 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 (MoveList<LEGAL> it(pos); *it; ++it)
- if (str == UCI::move(*it, pos.is_chess960()))
- return *it;
+ for (const auto& m : MoveList<LEGAL>(pos))
+ if (str == UCI::move(m, pos.is_chess960()))
+ return m;
return MOVE_NONE;
}