<< endl;
}
+ // Start async mode to catch UCI commands sent to us while searching,
+ // like "quit", "stop", etc.
+ Threads.start_listener();
+
// We're ready to start thinking. Call the iterative deepening loop function
Move ponderMove = MOVE_NONE;
Move bestMove = id_loop(pos, searchMoves, &ponderMove);
// This makes all the threads to go to sleep
Threads.set_size(1);
+ // From now on any UCI command will be read in-sync with Threads.getline()
+ Threads.stop_listener();
+
// If we are pondering or in infinite search, we shouldn't print the
// best move before we are told to do so.
if (!StopRequest && (Limits.ponder || Limits.infinite))
static int lastInfoTime;
int t = current_search_time();
- // Poll for input
- if (input_available())
- {
- // We are line oriented, don't read single chars
- string command;
-
- if (!std::getline(std::cin, command) || command == "quit")
- {
- // Quit the program as soon as possible
- Limits.ponder = false;
- QuitRequest = StopRequest = true;
- return;
- }
- else if (command == "stop")
- {
- // Stop calculating as soon as possible, but still send the "bestmove"
- // and possibly the "ponder" token when finishing the search.
- Limits.ponder = false;
- StopRequest = true;
- }
- else if (command == "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.
- Limits.ponder = false;
-
- if (StopOnPonderhit)
- StopRequest = true;
- }
- }
-
// Print search information
if (t < 1000)
lastInfoTime = 0;
void wait_for_stop_or_ponderhit() {
- string command;
+ string cmd;
// Wait for a command from stdin
- while ( std::getline(std::cin, command)
- && command != "ponderhit" && command != "stop" && command != "quit") {};
+ while (cmd != "ponderhit" && cmd != "stop" && cmd != "quit")
+ Threads.getline(cmd);
- if (command != "ponderhit" && command != "stop")
- QuitRequest = true; // Must be "quit" or getline() returned false
+ if (cmd == "quit")
+ QuitRequest = true;
}
}
}
}
+
+
+// ThreadsManager::do_uci_async_cmd() processes the commands from GUI received
+// by listener thread while the other threads are searching.
+
+void ThreadsManager::do_uci_async_cmd(const std::string& cmd) {
+
+ if (cmd == "quit")
+ {
+ // Quit the program as soon as possible
+ Limits.ponder = false;
+ QuitRequest = StopRequest = true;
+ }
+ else if (cmd == "stop")
+ {
+ // Stop calculating as soon as possible, but still send the "bestmove"
+ // and possibly the "ponder" token when finishing the search.
+ Limits.ponder = false;
+ StopRequest = true;
+ }
+ else if (cmd == "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.
+ Limits.ponder = false;
+
+ if (StopOnPonderhit)
+ StopRequest = true;
+ }
+}
namespace { extern "C" {
// start_routine() is the C function which is called when a new thread
- // is launched. It simply calls idle_loop() of the supplied thread.
- // There are two versions of this function; one for POSIX threads and
- // one for Windows threads.
+ // is launched. It simply calls idle_loop() of the supplied thread. The
+ // last thread is dedicated to I/O and so runs in listener_loop().
#if defined(_MSC_VER)
-
DWORD WINAPI start_routine(LPVOID thread) {
-
- ((Thread*)thread)->idle_loop(NULL);
- return 0;
- }
-
#else
-
void* start_routine(void* thread) {
+#endif
- ((Thread*)thread)->idle_loop(NULL);
- return NULL;
- }
+ if (((Thread*)thread)->threadID == MAX_THREADS)
+ ((Thread*)thread)->listener_loop();
+ else
+ ((Thread*)thread)->idle_loop(NULL);
-#endif
+ return 0;
+ }
} }
void ThreadsManager::init() {
+ // Initialize sleep condition used to block waiting for GUI input
+ cond_init(&sleepCond);
+
// Initialize threads lock, used when allocating slaves during splitting
lock_init(&threadsLock);
// Initialize sleep and split point locks
- for (int i = 0; i < MAX_THREADS; i++)
+ for (int i = 0; i <= MAX_THREADS; i++)
{
lock_init(&threads[i].sleepLock);
cond_init(&threads[i].sleepCond);
// Create and launch all the threads but the main that is already running,
// threads will go immediately to sleep.
- for (int i = 1; i < MAX_THREADS; i++)
+ for (int i = 1; i <= MAX_THREADS; i++)
{
threads[i].is_searching = false;
threads[i].threadID = i;
void ThreadsManager::exit() {
- // Wake up all the slave threads at once. This is faster than "wake and wait"
- // for each thread and avoids a rare crash once every 10K games under Linux.
- for (int i = 1; i < MAX_THREADS; i++)
- {
- threads[i].do_terminate = true;
- threads[i].wake_up();
- }
-
- for (int i = 0; i < MAX_THREADS; i++)
+ for (int i = 0; i <= MAX_THREADS; i++)
{
if (i != 0)
{
+ threads[i].do_terminate = true;
+ threads[i].wake_up();
+
// Wait for slave termination
#if defined(_MSC_VER)
WaitForSingleObject(threads[i].handle, 0);
}
lock_destroy(&threadsLock);
+ cond_destroy(&sleepCond);
}
// Explicit template instantiations
template Value ThreadsManager::split<false>(Position&, SearchStack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
template Value ThreadsManager::split<true>(Position&, SearchStack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
+
+
+// Thread::listner_loop() is where the last thread, used for IO, waits for input.
+// Input is read in sync with main thread (that blocks) when is_searching is set
+// to false, otherwise IO thread reads any input asynchronously and processes
+// the input line calling do_uci_async_cmd().
+
+void Thread::listener_loop() {
+
+ std::string cmd;
+
+ while (true)
+ {
+ lock_grab(&sleepLock);
+
+ Threads.inputLine = cmd;
+ do_sleep = !is_searching;
+
+ // Here the thread is parked in sync mode after a line has been read
+ while (do_sleep && !do_terminate) // Catches spurious wake ups
+ {
+ cond_signal(&Threads.sleepCond); // Wake up main thread
+ cond_wait(&sleepCond, &sleepLock); // Sleep here
+ }
+
+ lock_release(&sleepLock);
+
+ if (do_terminate)
+ return;
+
+ if (!std::getline(std::cin, cmd)) // Block waiting for input
+ cmd = "quit";
+
+ lock_grab(&sleepLock);
+
+ // If we are in async mode then process the command now
+ if (is_searching)
+ {
+ // Command "quit" is the last one received by the GUI, so park the
+ // thread waiting for exiting.
+ if (cmd == "quit")
+ is_searching = false;
+
+ Threads.do_uci_async_cmd(cmd);
+ cmd = ""; // Input has been consumed
+ }
+
+ lock_release(&sleepLock);
+ }
+}
+
+
+// ThreadsManager::getline() is used by main thread to block and wait for input,
+// the behaviour mimics std::getline().
+
+void ThreadsManager::getline(std::string& cmd) {
+
+ Thread& listener = threads[MAX_THREADS];
+
+ lock_grab(&listener.sleepLock);
+
+ listener.is_searching = false; // Set sync mode
+
+ // If there is already some input to grab then skip without to wake up the
+ // listener. This can happen if after we send the "bestmove", the GUI sends
+ // a command that the listener buffers in inputLine before going to sleep.
+ if (inputLine.empty())
+ {
+ listener.do_sleep = false;
+ cond_signal(&listener.sleepCond); // Wake up listener thread
+
+ while (!listener.do_sleep)
+ cond_wait(&sleepCond, &listener.sleepLock); // Wait for input
+ }
+
+ cmd = inputLine;
+ inputLine = ""; // Input has been consumed
+
+ lock_release(&listener.sleepLock);
+}
+
+
+// ThreadsManager::start_listener() is called at the beginning of the search to
+// swith from sync behaviour (default) to async and so be able to read from UCI
+// while other threads are searching. This avoids main thread polling for input.
+
+void ThreadsManager::start_listener() {
+
+ Thread& listener = threads[MAX_THREADS];
+
+ lock_grab(&listener.sleepLock);
+ listener.is_searching = true;
+ listener.do_sleep = false;
+ cond_signal(&listener.sleepCond); // Wake up listener thread
+ lock_release(&listener.sleepLock);
+}
+
+
+// ThreadsManager::stop_listener() is called before to send "bestmove" to GUI to
+// return to in-sync behaviour. This is needed because while in async mode any
+// command is discarded without being processed (except for a very few ones).
+
+void ThreadsManager::stop_listener() {
+
+ Thread& listener = threads[MAX_THREADS];
+
+ lock_grab(&listener.sleepLock);
+ listener.is_searching = false;
+ lock_release(&listener.sleepLock);
+}
projects / stockfish / commitdiff