Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, 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 <cassert>
#include <iostream>
#include <sstream>
#include <string>
#include "search.h"
#include "thread.h"
#include "tt.h"
+#include "timeman.h"
#include "uci.h"
+#include "syzygy/tbprobe.h"
using namespace std;
// 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;
-
// 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) {
+ void position(Position& pos, istringstream& is, StateListPtr& states) {
Move m;
string token, fen;
else
return;
- pos.set(fen, Options["UCI_Chess960"], Threads.main());
- SetupStates = Search::StateStackPtr(new std::stack<StateInfo>());
+ states = StateListPtr(new std::deque<StateInfo>(1)); // Drop old and create a new one
+ pos.set(fen, Options["UCI_Chess960"], &states->back(), Threads.main());
// 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());
+ states->emplace_back();
+ pos.do_move(m, states->back());
}
}
// Read option name (can contain spaces)
while (is >> token && token != "value")
- name += string(" ", !name.empty()) + token;
+ name += string(" ", name.empty() ? 0 : 1) + token;
// Read option value (can contain spaces)
while (is >> token)
- value += string(" ", !value.empty()) + token;
+ value += string(" ", value.empty() ? 0 : 1) + token;
if (Options.count(name))
Options[name] = value;
// the thinking time and other parameters from the input string, then starts
// the search.
- void go(const Position& pos, istringstream& is) {
+ void go(Position& pos, istringstream& is, StateListPtr& states) {
Search::LimitsType limits;
string token;
+ bool ponderMode = false;
+
+ limits.startTime = now(); // As early as possible!
while (is >> token)
if (token == "searchmoves")
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;
+ else if (token == "infinite") limits.infinite = 1;
+ else if (token == "ponder") ponderMode = true;
- Threads.start_thinking(pos, limits, SetupStates);
+ Threads.start_thinking(pos, states, limits, ponderMode);
}
} // namespace
void UCI::loop(int argc, char* argv[]) {
- Position pos(StartFEN, false, Threads.main()); // The root position
+ Position pos;
string token, cmd;
+ StateListPtr states(new std::deque<StateInfo>(1));
+ auto uiThread = std::make_shared<Thread>(0);
+
+ pos.set(StartFEN, false, &states->back(), uiThread.get());
for (int i = 1; i < argc; ++i)
cmd += std::string(argv[i]) + " ";
istringstream is(cmd);
- token.clear(); // getline() could return empty or blank line
+ token.clear(); // Avoid a stale if getline() returns 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.
+ // The GUI sends 'ponderhit' to tell us the user has played the expected move.
+ // So 'ponderhit' will be sent if we were told to ponder on the same move the
+ // user has played. We should continue searching but switch from pondering to
+ // normal search. In case Threads.stopOnPonderhit is set we are waiting for
+ // 'ponderhit' to stop the search, for instance if max search depth is reached.
if ( token == "quit"
|| token == "stop"
- || (token == "ponderhit" && Search::Signals.stopOnPonderhit))
- {
- Search::Signals.stop = true;
- Threads.main()->notify_one(); // Could be sleeping
- }
+ || (token == "ponderhit" && Threads.stopOnPonderhit))
+ Threads.stop = true;
+
else if (token == "ponderhit")
- Search::Limits.ponder = false; // Switch to normal search
+ Threads.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);
+ else if (token == "go") go(pos, is, states);
+ else if (token == "position") position(pos, is, states);
+ else if (token == "ucinewgame") Search::clear();
+ else if (token == "isready") sync_cout << "readyok" << sync_endl;
- // 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;
+ // Additional custom non-UCI commands, mainly 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";
+ 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
+ } while (token != "quit" && argc == 1); // Command line args are one-shot
}
string UCI::value(Value v) {
+ assert(-VALUE_INFINITE < v && v < VALUE_INFINITE);
+
stringstream ss;
if (abs(v) < VALUE_MATE - MAX_PLY)
/// 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 }; // NULL terminated
- return sq;
+ return std::string{ char('a' + file_of(s)), char('1' + rank_of(s)) };
}
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;
}