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  1. // chessengine.cpp
  2.  
  3. #include "common.h"
  4.  
  5.  
  6. // global variables used in this module only
  7. static wchar_t chessengine_path[MAX_PATH];
  8. static wchar_t chessengine_shellcommand[MAX_PATH];
  9. static wchar_t chessengineinitfile_pathname[MAX_PATH];
  10. static int current_obstinacy;
  11. static int max_cores;
  12. static bool is_hint_pending;
  13. static bool should_initialize;
  14. FILE *fpipe;
  15.  
  16. // prototypes of local functions
  17. static void PlayerEngine_Recv (player_t *player);
  18. static void PlayerEngine_Send (player_t *player);
  19. static wchar_t *Move_BuildString (boardmove_t *move);
  20.  
  21.  
  22. bool PlayerEngine_Init (player_t *player)
  23. {
  24.    // this function starts a chess engine as a child process. This process's stdin and
  25.    // stdout are redirected to the handles we give it, so that we may read/write to it.
  26.  
  27.    engineprogram_t *program;
  28.    wchar_t current_path[MAX_PATH];
  29.    wchar_t widechar_buffer[1024];
  30.    SYSTEM_INFO sysinfo;
  31.    FILE *fp;
  32.  
  33.    // reset stuff first
  34.    player->wants_hint = false;
  35.  
  36.    // quick access to engine program
  37.    program = &options.engine.programs[options.engine.selected_program];
  38.  
  39.    // build the chess engine module path and pathname
  40.    swprintf_s (chessengine_path, WCHAR_SIZEOF (chessengine_path), L"%s/engines/%s", app_path, program->folder);
  41.    swprintf_s (chessengine_shellcommand, WCHAR_SIZEOF (chessengine_shellcommand), L"\"%s/%s\" %s", chessengine_path, program->executable_name, program->executable_arguments);
  42.  
  43.    // start the engine behind a bidirectional I/O pipe
  44.    GetCurrentDirectory (WCHAR_SIZEOF (current_path), current_path); // save current directory
  45.    SetCurrentDirectory (chessengine_path); // temporarily set chess engine's startup directory as current directory
  46.    fpipe = pipe_open (chessengine_shellcommand, L"r+");
  47.    SetCurrentDirectory (current_path); // restore current directory
  48.    if (fpipe == NULL)
  49.    {
  50.       messagebox.hWndParent = hMainWnd;
  51.       wcscpy_s (messagebox.title, WCHAR_SIZEOF (messagebox.title), LOCALIZE (L"ImportantMessage"));
  52.       wcscpy_s (messagebox.text, WCHAR_SIZEOF (messagebox.text), LOCALIZE (L"Error_ChessEngineInitializationFailed"));
  53.       messagebox.flags = MB_ICONWARNING | MB_OK;
  54.       DialogBox_Message (&messagebox); // display a modeless error message box
  55.  
  56.       PlayerEngine_Shutdown (player); // on error, shutdown the engine
  57.       return (false);
  58.    }
  59.  
  60.    // SMP HACK -- save the max CPUs to use to core max - 1 (the computer will look like hung if all CPU is taken)
  61.    GetSystemInfo (&sysinfo); // get the number of cores
  62.    max_cores = max (1, sysinfo.dwNumberOfProcessors - 1);
  63.  
  64.    // optionally initialize the debug log file
  65.    Debug_Init (L"Chess engine output.txt");
  66.    Debug_Log (L"===Using engine: %s [%s]===\n", program->friendly_name, chessengine_shellcommand);
  67.  
  68.    // build the init file full qualified path name and try to open it
  69.    swprintf_s (chessengineinitfile_pathname, WCHAR_SIZEOF (chessengineinitfile_pathname), L"%s/engines/%s/init.txt", app_path, program->folder);
  70.    _wfopen_s (&fp, chessengineinitfile_pathname, L"r");
  71.  
  72.    // could the init file be opened ?
  73.    if (fp != NULL)
  74.    {
  75.       Debug_Log (L"===Found initialization file, parsing...===\n", chessengineinitfile_pathname);
  76.  
  77.       // read line per line
  78.       while (fgetws (widechar_buffer, WCHAR_SIZEOF (widechar_buffer), fp) != NULL)
  79.       {
  80.          if ((widechar_buffer[0] == L'#') || (widechar_buffer[0] == L'\n'))
  81.             continue; // skip comments and empty lines
  82.  
  83.          // new command line found, append it to the send buffer
  84.          Player_SendBuffer_Add (player, 1000, widechar_buffer);
  85.       }
  86.  
  87.       fclose (fp); // finished, close the file
  88.    }
  89.  
  90.    // everything's okay, set engine name as the player's name
  91.    wcscpy_s (player->name, WCHAR_SIZEOF (player->name), program->friendly_name);
  92.  
  93.    should_initialize = true; // remember the engine should be initialized
  94.    return (true); // finished
  95. }
  96.  
  97.  
  98. void PlayerEngine_Shutdown (player_t *player)
  99. {
  100.    // this function terminates the chess engine process and releases all handles attached to it
  101.  
  102.    int attempt_index;
  103.  
  104.    // send the engine a quit command
  105.    Player_SendBuffer_Add (player, 1000, options.engine.programs[options.engine.selected_program].command_quit);
  106.    Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  107.    PlayerEngine_Send (player);
  108.  
  109.    // check 10 times if the engine process has ended cleanly
  110.    for (attempt_index = 0; attempt_index < 10; attempt_index++)
  111.    {
  112.       if (!pipe_isalive (fpipe))
  113.          break; // break as soon as we've told the process exited cleanly
  114.  
  115.       Sleep (100); // else wait one tenth second
  116.    }
  117.  
  118.    // close the pipe (this will terminate the child process if it hasn't terminated yet)
  119.    pipe_close (fpipe);
  120.  
  121.    Debug_Log (L"===Engine closed===\n");
  122.    return; // finished
  123. }
  124.  
  125.  
  126. bool PlayerEngine_Think (player_t *player)
  127. {
  128.    // this function reads and writes any necessary data from and to the chess engine. Returns TRUE if scene needs to be updated.
  129.  
  130.    engineprogram_t *program;
  131.    wchar_t line_buffer[1024];
  132.    wchar_t *line_pointer;
  133.    wchar_t *move_string;
  134.    int char_index;
  135.    int length;
  136.    boardmove_t move;
  137.    player_t *current_player;
  138.    player_t *opposite_player;
  139.    bool do_update;
  140.  
  141.    // quick access to chess engine program
  142.    program = &options.engine.programs[options.engine.selected_program];
  143.  
  144.    // don't update the scene until told otherwise
  145.    do_update = false;
  146.  
  147.    // get current and opposite players
  148.    current_player = Player_GetCurrent ();
  149.    opposite_player = Player_GetOpposite ();
  150.  
  151.    // is the game still alive AND has the engine just died ?
  152.    if ((the_board.game_state == STATE_PLAYING) && !pipe_isalive (fpipe))
  153.    {
  154.       Debug_Log (L"===Unrecoverable engine error: opponent wins!===\n");
  155.  
  156.       // if opponent player is human, play the victory sound, else, play defeat sound at the center of the board
  157.       Audio_PlaySound (opposite_player->type == PLAYER_HUMAN ? SOUNDTYPE_VICTORY : SOUNDTYPE_DEFEAT, 0.0f, 0.0f, 0.04f);
  158.  
  159.       // display a crash notification dialog box
  160.       if (MessageBox (hMainWnd, LOCALIZE (L"Error_EngineCrashed"), LOCALIZE (L"ImportantMessage"), MB_ICONWARNING | MB_YESNO) == IDYES)
  161.          if (Debug_SendLogToAuthor (true))
  162.             MessageBox (hMainWnd, LOCALIZE (L"MessageSent"), PROGRAM_NAME, MB_ICONINFORMATION | MB_OK); // send the game engine history to the author
  163.          else
  164.             MessageBox (hMainWnd, LOCALIZE (L"NoInternetConnection"), LOCALIZE (L"FatalError"), MB_ICONWARNING | MB_OK); // and display an error message if failed
  165.  
  166.       // and display the game over dialog box
  167.       the_board.game_state = (opposite_player->color == COLOR_BLACK ? STATE_WHITEWIN_RESIGNORFORFEIT : STATE_BLACKWIN_RESIGNORFORFEIT);
  168.       DialogBox_EndGame ();
  169.  
  170.       do_update = true; // remember to update the 3D scene
  171.    }
  172.  
  173.    // read from pipe (non-blocking)
  174.    PlayerEngine_Recv (player);
  175.  
  176.    ////////////////
  177.    // START PARSING
  178.  
  179.    // read line per line...
  180.    line_pointer = player->recvbuffer; // start at the first character
  181.    while ((line_pointer = ReadACompleteLine (line_buffer, WCHAR_SIZEOF (line_buffer), line_pointer)) != NULL)
  182.    {
  183.       // is it an empty line or engine noise ?
  184.       if ((line_buffer[0] == 0) || iswspace (line_buffer[0]))
  185.          continue; // skip empty lines and engine noise
  186.  
  187.       // is the engine offering us a draw ?
  188.       if (wcsncmp (line_buffer, L"offer draw", 10) == 0)
  189.          continue; // if so, discard its offer (engine draws are unsupported) and proceed to the next line
  190.  
  191.       // else is it an *irrevocable* draw ? (at this point there's nothing we can do but accept it)
  192.       else if (wcsstr (line_buffer, L"1/2-1/2") != NULL)
  193.       {
  194.          Debug_Log (L"===Engine tells us that it's a draw: nobody wins!===\n");
  195.  
  196.          // play defeat sound (a draw is always a sort of defeat...) at the center of the board
  197.          Audio_PlaySound (SOUNDTYPE_DEFEAT, 0.0f, 0.0f, 0.04f);
  198.  
  199.          // display the game over dialog box
  200.          the_board.game_state = STATE_DRAW_OTHER;
  201.          DialogBox_EndGame ();
  202.  
  203.          do_update = true; // remember to update the 3D scene
  204.          continue; // we processed that line
  205.       }
  206.  
  207.       // else is the engine *irrevocably* resigning ? (at this point there's nothing we can do but accept it)
  208.       else if (wcsncmp (line_buffer, L"resign", 6) == 0)
  209.       {
  210.          Debug_Log (L"===Engine tells us that %s resigns: %s wins!===\n", (current_player->color == COLOR_BLACK ? "black" : "white"), (current_player->color == COLOR_BLACK ? "white" : "black"));
  211.  
  212.          // if opponent player is human, play the victory sound, else, play defeat sound at the center of the board
  213.          Audio_PlaySound (opposite_player->type == PLAYER_HUMAN ? SOUNDTYPE_VICTORY : SOUNDTYPE_DEFEAT, 0.0f, 0.0f, 0.04f);
  214.  
  215.          // display the game over dialog box
  216.          the_board.game_state = (current_player->color == COLOR_BLACK ? STATE_WHITEWIN_RESIGNORFORFEIT : STATE_BLACKWIN_RESIGNORFORFEIT);
  217.          DialogBox_EndGame ();
  218.  
  219.          do_update = true; // remember to update the 3D scene
  220.          continue; // we processed that line
  221.       }
  222.  
  223.       // is engine allowed to resign ? if so, check if it's a game results
  224.       if (options.engine.obstinacy_level >= 0)
  225.       {
  226.          // is it a game result AND are we still in play ?
  227.          if ((wcsstr (line_buffer, L"1-0") != NULL) && (the_board.game_state == STATE_PLAYING))
  228.          {
  229.             // have we NOT been obstinate enough ?
  230.             if (current_obstinacy < options.engine.obstinacy_level)
  231.                current_obstinacy++; // if so, discard this resign and go on
  232.             else
  233.             {
  234.                Debug_Log (L"===Engine tells us that black resigns: white wins!===\n");
  235.  
  236.                // if opponent player is human, play the victory sound, else, play defeat sound at the center of the board
  237.                Audio_PlaySound (opposite_player->type == PLAYER_HUMAN ? SOUNDTYPE_VICTORY : SOUNDTYPE_DEFEAT, 0.0f, 0.0f, 0.04f);
  238.  
  239.                // display the game over dialog box
  240.                the_board.game_state = STATE_WHITEWIN_RESIGNORFORFEIT;
  241.                DialogBox_EndGame ();
  242.  
  243.                do_update = true; // remember to update the 3D scene
  244.             }
  245.  
  246.             continue; // we processed that line
  247.          }
  248.          else if ((wcsstr (line_buffer, L"0-1") != NULL) && (the_board.game_state == STATE_PLAYING))
  249.          {
  250.             // have we NOT been obstinate enough ?
  251.             if (current_obstinacy < options.engine.obstinacy_level)
  252.                current_obstinacy++; // if so, discard this resign and go on
  253.             else
  254.             {
  255.                Debug_Log (L"===Engine tells us that white resigns: black wins!===\n");
  256.  
  257.                // if opponent player is human, play the victory sound, else, play defeat sound at the center of the board
  258.                Audio_PlaySound (opposite_player->type == PLAYER_HUMAN ? SOUNDTYPE_VICTORY : SOUNDTYPE_DEFEAT, 0.0f, 0.0f, 0.04f);
  259.  
  260.                // display the game over dialog box
  261.                the_board.game_state = STATE_BLACKWIN_RESIGNORFORFEIT;
  262.                DialogBox_EndGame ();
  263.  
  264.                do_update = true; // remember to update the 3D scene
  265.             }
  266.  
  267.             continue; // we processed that line
  268.          }
  269.       }
  270.  
  271.       // has the game ended already ?
  272.       if (the_board.game_state > STATE_PLAYING)
  273.          continue; // ignore all that the engine tells us. Game is over already.
  274.  
  275.       // else is it an unrecoverable engine error ?
  276.       else if ((wcsstr (line_buffer, L"illegal") != NULL) || (wcsstr (line_buffer, L"invalid") != NULL))
  277.       {
  278.          Debug_Log (L"===Unrecoverable engine error: opponent wins!===\n");
  279.  
  280.          // if opponent player is human, play the victory sound, else, play defeat sound at the center of the board
  281.          Audio_PlaySound (opposite_player->type == PLAYER_HUMAN ? SOUNDTYPE_VICTORY : SOUNDTYPE_DEFEAT, 0.0f, 0.0f, 0.04f);
  282.  
  283.          // display a crash notification dialog box
  284.          if (MessageBox (hMainWnd, LOCALIZE (L"Error_EngineCrashed"), LOCALIZE (L"ImportantMessage"), MB_ICONWARNING | MB_YESNO) == IDYES)
  285.             if (Debug_SendLogToAuthor (true))
  286.                MessageBox (hMainWnd, LOCALIZE (L"MessageSent"), PROGRAM_NAME, MB_ICONINFORMATION | MB_OK); // send the game engine history to the author
  287.             else
  288.                MessageBox (hMainWnd, LOCALIZE (L"NoInternetConnection"), LOCALIZE (L"FatalError"), MB_ICONWARNING | MB_OK); // and display an error message if failed
  289.  
  290.          // and display the game over dialog box
  291.          the_board.game_state = (opposite_player->color == COLOR_BLACK ? STATE_WHITEWIN_RESIGNORFORFEIT : STATE_BLACKWIN_RESIGNORFORFEIT);
  292.          DialogBox_EndGame ();
  293.  
  294.          do_update = true; // remember to update the 3D scene
  295.       }
  296.  
  297.       // else is it a normal move ?
  298.       else if ((move_string = wcsstr (line_buffer, program->replystring_move)) != NULL)
  299.          move_string += wcslen (program->replystring_move); // go to the parsable data
  300.  
  301.       // else it's any other sort of line
  302.       else
  303.          continue; // skip lines that don't contain any valid move data
  304.  
  305.       // now we are sure it's either a hint or a move (or some pondering)
  306.  
  307.       length = wcslen (move_string);
  308.       if (length < 2)
  309.          continue; // if string is too short to be a move, skip it
  310.  
  311.       // there must be valid move data on that line.
  312.  
  313.       // evaluate the engine move string
  314.       memcpy (move.slots, the_board.moves[the_board.move_count - 1].slots, sizeof (move.slots));
  315.       char_index = 0;
  316.       while ((move_string[char_index] != 0) && !iswspace (move_string[char_index]))
  317.       {
  318.          move.pgntext[char_index] = move_string[char_index];
  319.          char_index++;
  320.       }
  321.       move.pgntext[char_index] = 0;
  322.       if (!Move_SetupFromSAN (&the_board.moves[the_board.move_count - 1], &move, Board_ColorToMove (&the_board)))
  323.       {
  324.          Debug_Log (L"===Skipping line (invalid move syntax)===\n%s", move_string);
  325.          continue; // so now, if there are NOT two digits AND it's not a kind of castle, it can't be a move so skip that line
  326.       }
  327.  
  328.       // is it NOT a hint, are blunders allowed, should we do one now AND can we do one now ?
  329.       if (!is_hint_pending && (options.engine.blunder_chances > 0) && (rand () % 100 < options.engine.blunder_chances)
  330.           && Move_FindRandomMove (&the_board.moves[the_board.move_count - 1], player->color, &move))
  331.       {
  332.          if (program->command_force[0] != 0)
  333.          {
  334.             Player_SendBuffer_Add (player, 1000, program->command_force, Move_BuildString (&move)); // send the blunderous move to the engine
  335.             Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  336.             if (_wcsnicmp (program->friendly_name, L"Crafty", 6) == 0)
  337.                Player_SendBuffer_Add (player, 1000, L"disp\n"); // FIXME: we no longer need this Crafty-specific hack, do we?
  338.          }
  339.          Debug_Log (L"===Discarding engine move, forcing a blunderous move (%s) instead===\n", Move_BuildString (&move)); // blunder
  340.       }
  341.  
  342.       // mark the engine's selected and hovered squares
  343.       Board_SetSelectedAndHovered (&the_board, move.source[0], move.source[1], move.target[0], move.target[1]);
  344.  
  345.       // was it NOT a hint ?
  346.       if (!is_hint_pending)
  347.       {
  348.          the_scene.gui.central_text.disappear_time = current_time + 1.0f; // fade the "thinking" phrase out now (FIXME: ugly)
  349.          the_scene.gui.want_spinwheel = false; // stop spinning wheel
  350.  
  351.          Board_AppendMove (&the_board, the_board.selected_position[0], the_board.selected_position[1], the_board.hovered_position[0], the_board.hovered_position[1], move.promotion_type, NULL);
  352.          Player_GetOpposite ()->should_wakeup = true; // do the movement and switch players
  353.  
  354.          // forget the hovered and selected positions
  355.          Board_SetSelectedAndHovered (&the_board, -1, -1, -1, -1);
  356.          animation_endtime = current_time + ANIMATION_DURATION; // wait for animation time seconds
  357.       }
  358.  
  359.       // else it was a hint
  360.       else
  361.       {
  362.          the_scene.gui.central_text.disappear_time = current_time + 0.1f; // fade the "thinking" phrase out now quickly (FIXME: ugly)
  363.          the_scene.gui.want_spinwheel = false; // stop spinning wheel
  364.  
  365.          highlight_endtime = current_time + 2.0f; // just highlight this part for a little more than one second
  366.          is_hint_pending = false; // remember no hint is pending any longer
  367.  
  368.          // we must now restore the board to its last state. Just set up the board again from its current Forsyth-Edwards notation
  369.          Debug_Log (L"===Hint received, rebuilding board and telling engine to backup 1 move===\n");
  370.          Debug_Log (L"===setting up board using FEN string===\n");
  371.  
  372.          // get the current game state in FEN format and feed it to the engine
  373.          Player_SendBuffer_Add (player, 1000, program->command_setboard, the_board.moves[the_board.move_count - 1].fen_string);
  374.          Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  375.  
  376.          if (_wcsnicmp (program->friendly_name, L"Crafty", 6) == 0)
  377.             Player_SendBuffer_Add (player, 1000, L"disp\n"); // FIXME: we no longer need this Crafty-specific hack, do we?
  378.       }
  379.  
  380.       do_update = true; // remember to update the 3D scene
  381.    }
  382.  
  383.    // now clean the input buffer of all the lines we parsed
  384.    line_pointer = wcsrchr (player->recvbuffer, L'\n'); // reach the last carriage return
  385.    if (line_pointer != NULL)
  386.    {
  387.       line_pointer++; // skip the carriage return
  388.       length = wcslen (line_pointer); // get the remaining string length
  389.       for (char_index = 0; char_index < length; char_index++)
  390.          player->recvbuffer[char_index] = line_pointer[char_index]; // and recopy the remaining string at the beginning of the buffer
  391.       player->recvbuffer[char_index] = 0; // finish the string ourselves
  392.    }
  393.  
  394.    // END PARSING
  395.    //////////////
  396.  
  397.    /////////////////////////////////
  398.    // START NOTIFICATIONS PROCESSING
  399.  
  400.    // have we been notified that the board was just set up ?
  401.    if (the_board.was_setup)
  402.    {
  403.       Debug_Log (L"===Got board setup notification from interface===\n");
  404.  
  405.       // send a new game command to the chess engine
  406.       Player_SendBuffer_Add (player, 1000, program->command_new);
  407.       Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  408.  
  409.       // just set up the board from its Forsyth-Edwards notation
  410.       Debug_Log (L"===setting up board using FEN string===\n");
  411.  
  412.       // get the current game state in FEN format and feed it to the engine
  413.       Player_SendBuffer_Add (player, 1000, program->command_setboard, the_board.moves[the_board.move_count - 1].fen_string);
  414.       Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  415.  
  416.       current_obstinacy = 0; // reset current obstinacy
  417.       is_hint_pending = false; // no hint was requested so far
  418.  
  419.       if (_wcsnicmp (program->friendly_name, L"Crafty", 6) == 0)
  420.          Player_SendBuffer_Add (player, 1000, L"disp\n"); // FIXME: we no longer need this Crafty-specific hack, do we?
  421.    }
  422.  
  423.    // have we been notified that players are swapping colors ? (N.B. when this happens in human vs. computer mode, it's always that the human player is *GIVING* his turn)
  424.    if (the_board.want_playerswap)
  425.    {
  426.       Debug_Log (L"===Got player SWAP notification from interface===\n");
  427.       Player_SendBuffer_Add (player, 1000, program->command_go); // tell engine it's now the current player
  428.       Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  429.    }
  430.  
  431.    // have we been notified that the current player just changed AND is the animation finished ?
  432.    if (player->should_wakeup && (animation_endtime < current_time))
  433.    {
  434.       Debug_Log (L"===Got player change notification from interface===\n");
  435.  
  436.       // is the current player our color ? (meaning is it engine's turn to play) ?
  437.       if (Board_ColorToMove (&the_board) == player->color)
  438.       {
  439.          // is it NOT a board setup AND has at least one move been played (meaning it was just the other's turn before) ?
  440.          if (!the_board.was_setup && (the_board.move_count > 1))
  441.          {
  442.             Debug_Log (L"===Player just played, sending the chosen move to engine===\n");
  443.             if (_wcsnicmp (program->friendly_name, L"Crafty", 6) == 0)
  444.                Player_SendBuffer_Add (player, 1000, L"disp\n"); // FIXME: we no longer need this Crafty-specific hack, do we?
  445.  
  446.             // build the move string, and send the move string to the engine
  447.             Player_SendBuffer_Add (player, 1000, program->command_move, Move_BuildString (&the_board.moves[the_board.move_count - 1]));
  448.             Player_SendBuffer_Add (player, 1000, L"\n"); // end the send buffer with a carriage return
  449.          }
  450.  
  451.          // else game has not started yet, but it's our turn
  452.          else
  453.          {
  454.             Player_SendBuffer_Add (player, 1000, program->command_go); // so let's start the game
  455.             Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  456.          }
  457.       }
  458.  
  459.       player->should_wakeup = false; // remember we taken this notification in account
  460.    }
  461.  
  462.    // END NOTIFICATIONS PROCESSING
  463.    ///////////////////////////////
  464.  
  465.    // is it NOT our turn ?
  466.    if (current_player != player)
  467.    {
  468.       // does our opponent want a hint ?
  469.       if (current_player->wants_hint)
  470.       {
  471.          current_player->wants_hint = false; // don't ask twice
  472.          Debug_Log (L"===Hint requested, asking engine for it===\n");
  473.          Player_SendBuffer_Add (player, 1000, program->command_go); // tell the computer to analyze this position
  474.          Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  475.          is_hint_pending = true; // remember a hint is pending
  476.  
  477.          // FIXME: move to scene.cpp
  478.          Scene_UpdateText (&the_scene.gui.central_text, RGBA_TO_RGBACOLOR (255, 255, 255, 191), DURATION_INFINITE, true, LOCALIZE (L"Thinking")); // display the "thinking" phrase in the middle of the screen
  479.          the_scene.gui.want_spinwheel = true; // start spinning wheel
  480.          do_update = true; // remember to update the 3D scene
  481.       }
  482.  
  483.       // does our opponent want to cancel a move ?
  484.       if (current_player->wants_cancel)
  485.       {
  486.          current_player->wants_cancel = false; // don't ask twice (remember now before we switch players)
  487.          Debug_Log (L"===Move cancellation requested, rebuilding board and telling engine to backup 2 moves===\n");
  488.  
  489.          // rewind game 2 moves back
  490.          the_board.moves = (boardmove_t *) SAFE_realloc (the_board.moves, the_board.move_count, max (1, the_board.move_count - 2), sizeof (boardmove_t), false);
  491.          the_board.move_count = max (1, the_board.move_count - 2); // figure out how many moves we have now
  492.          the_board.viewed_move = the_board.move_count - 1; // take us back to the last move
  493.          the_board.game_state = STATE_PLAYING; // remember the game is now playing (in case we wanted to cancel the closing move of a finished game, this opens the game again)
  494.  
  495.          // just set up the board from its Forsyth-Edwards notation
  496.          Debug_Log (L"===setting up board using FEN string===\n");
  497.  
  498.          // get the current game state in FEN format and feed it to the engine
  499.          Player_SendBuffer_Add (player, 1000, program->command_setboard, the_board.moves[the_board.move_count - 1].fen_string);
  500.          Player_SendBuffer_Add (player, 1000, L"\n"); // since the format string was read from the options, don't forget to end it with a carriage return
  501.  
  502.          if (_wcsnicmp (program->friendly_name, L"Crafty", 6) == 0)
  503.             Player_SendBuffer_Add (player, 1000, L"disp\n"); // FIXME: we no longer need this Crafty-specific hack, do we?
  504.  
  505.          do_update = true; // remember to update the 3D scene
  506.       }
  507.    }
  508.  
  509.    // write to pipe (when we're allowed to)
  510.    if (!player->sendbuffer_locked && (animation_endtime + 1.0f < current_time))
  511.       PlayerEngine_Send (player);
  512.  
  513.    return (do_update); // finished, return whether we should update the scene or not
  514. }
  515.  
  516.  
  517. static void PlayerEngine_Recv (player_t *player)
  518. {
  519.    // helper function to read data from the pipe communicating with the game engine process
  520.  
  521.    //unsigned long amount_to_read;
  522.    unsigned long read_count;
  523.    int length;
  524.    unsigned int initial_pos;
  525.  
  526.    // get reception buffer's initial end position
  527.    initial_pos = wcslen (player->recvbuffer);
  528.    length = initial_pos;
  529.  
  530.    // as long as the pipe reports us there is data to read, read one byte at a time
  531.    while (pipe_hasdata (fpipe))
  532.    {
  533.       read_count = pipe_read (fpipe, player->ascii_recvbuffer, 1);
  534.       if (read_count == 0)
  535.          break; // read the pipe; if it fails, stop trying
  536.       if ((player->ascii_recvbuffer[0] == '\r') || (player->ascii_recvbuffer[0] == '%'))
  537.          continue; // ignore carriage returns and percent signs
  538.  
  539.       // convert the received character to wide char and append it to recvbuffer
  540.       player->ascii_recvbuffer[1] = 0; // terminate the received string ourselves
  541.       player->recvbuffer[length] = (wchar_t) player->ascii_recvbuffer[0];
  542.       //ConvertToWideChar (&player->recvbuffer[length], player->recvbuffer_size - length, player->ascii_recvbuffer);
  543.       length++; // there's one more character in the player's recv buffer
  544.       player->recvbuffer[length] = 0; // terminate the string ourselves
  545.    }
  546.  
  547.    // write what we received (if we received anything)
  548.    if (wcslen (player->recvbuffer) > initial_pos)
  549.       Debug_Log (L"===================================RECEIVED:===================================\n%s\n", &player->recvbuffer[initial_pos]);
  550.  
  551.    return; // finished
  552. }
  553.  
  554.  
  555. int wcs_replace (wchar_t *haystack, wchar_t *needle, wchar_t *replacement)
  556. {
  557.    size_t replacement_length;
  558.    size_t replacement_count;
  559.    size_t pattern_length;
  560.    wchar_t *line_pointer;
  561.  
  562.    replacement_count = 0;
  563.    while ((line_pointer = wcsstr (haystack, needle)) != NULL)
  564.    {
  565.       pattern_length = wcslen (needle);
  566.       replacement_length = wcslen (replacement);
  567.       memmove (&line_pointer[replacement_length], &line_pointer[pattern_length], (wcslen (&line_pointer[pattern_length]) + 1) * sizeof (wchar_t));
  568.       memcpy (line_pointer, replacement, replacement_length * sizeof (wchar_t));
  569.       replacement_count++;
  570.    }
  571.  
  572.    return (replacement_count);
  573. }
  574.  
  575.  
  576. static void PlayerEngine_Send (player_t *player)
  577. {
  578.    // helper function to send data through the pipe communicating with the game engine process
  579.  
  580.    static wchar_t replacement_string[65536];
  581.    static wchar_t widechar_buffer[65536]; // needs to be big enough to hold game history
  582.    static char ascii_buffer[65536]; // needs to be big enough to hold game history
  583.    wchar_t *line_pointer;
  584.    unsigned long amount_written;
  585.    int move_index;
  586.    int try_index;
  587.  
  588.    player->sendbuffer_locked = true; // lock the buffer
  589.  
  590.    // perform variable replacements on sendbuffer
  591.    if (the_board.move_count > 0)
  592.    {
  593.       wcs_replace (player->sendbuffer, L"${CURRENT_POS}", (/*the_board.move_count == 2 ? L"startpos" : */the_board.moves[the_board.move_count - 1].fen_string));
  594.       wcs_replace (player->sendbuffer, L"${LAST_MOVE}", Move_BuildString (&the_board.moves[the_board.move_count - 1]));
  595.       while (wcsstr (player->sendbuffer, L"${MAX_CORES}") != NULL)
  596.       {
  597.          swprintf_s (replacement_string, WCHAR_SIZEOF (replacement_string), L"%d", max_cores);
  598.          wcs_replace (player->sendbuffer, L"${MAX_CORES}", replacement_string);
  599.       }
  600.       while (wcsstr (player->sendbuffer, L"${SEARCH_DEPTH}") != NULL)
  601.       {
  602.          swprintf_s (replacement_string, WCHAR_SIZEOF (replacement_string), L"%d", options.engine.depth);
  603.          wcs_replace (player->sendbuffer, L"${SEARCH_DEPTH}", replacement_string);
  604.       }
  605.       while (wcsstr (player->sendbuffer, L"${GAME_HISTORY}") != NULL)
  606.       {
  607.          replacement_string[0] = 0;
  608.          for (move_index = 1; move_index < the_board.move_count; move_index++)
  609.          {
  610.             if (move_index > 1)
  611.                wcscat_s (replacement_string, WCHAR_SIZEOF (replacement_string), L" ");
  612.             wcscat_s (replacement_string, WCHAR_SIZEOF (replacement_string), Move_BuildString (&the_board.moves[move_index]));
  613.          }
  614.          wcs_replace (player->sendbuffer, L"${GAME_HISTORY}", replacement_string);
  615.       }
  616.    }
  617.  
  618.    // write what we're sending (if we're sending anything)
  619.    if (player->sendbuffer[0] != 0)
  620.       Debug_Log (L"====================================SENDING:===================================\n%s\n", player->sendbuffer);
  621.  
  622.    // now read line per line...
  623.    line_pointer = player->sendbuffer; // start at the first character
  624.    while ((line_pointer = wcsgets (widechar_buffer, WCHAR_SIZEOF (widechar_buffer), line_pointer)) != NULL)
  625.    {
  626.       wcscat_s (widechar_buffer, WCHAR_SIZEOF (widechar_buffer), L"\n"); // put the carriage return back
  627.       ConvertTo7BitASCII (ascii_buffer, sizeof (ascii_buffer), widechar_buffer); // convert to ASCII
  628.       amount_written = pipe_write (fpipe, ascii_buffer, strlen (ascii_buffer)); // send data
  629.    }
  630.  
  631.    player->sendbuffer[0] = 0; // what we had to send has been sent, reset the send buffer
  632.    player->sendbuffer_locked = false; // and unlock it
  633.  
  634.    // should the engine be initialized ?
  635.    if (should_initialize)
  636.    {
  637.       // wait for the engine process to display something (which will mean it's ready). Try for 5 seconds.
  638.       for (try_index = 0; try_index < 50; try_index++)
  639.       {
  640.          // read from pipe (non-blocking)
  641.          PlayerEngine_Recv (player);
  642.          if (player->recvbuffer[0] != 0)
  643.             break; // break as soon as we get something
  644.          Sleep (100); // next try in 100 milliseconds
  645.       }
  646.  
  647.       // has the engine process not spoken yet ?
  648.       if (player->recvbuffer[0] == 0)
  649.       {
  650.          messagebox.hWndParent = hMainWnd;
  651.          wcscpy_s (messagebox.title, WCHAR_SIZEOF (messagebox.title), LOCALIZE (L"ImportantMessage"));
  652.          swprintf_s (messagebox.text, WCHAR_SIZEOF (messagebox.text), LOCALIZE (L"Error_ChessEngineInitializationFailed"), options.engine.programs[options.engine.selected_program].folder);
  653.          messagebox.flags = MB_ICONWARNING | MB_OK;
  654.          DialogBox_Message (&messagebox); // display a modeless error message box
  655.  
  656.          PlayerEngine_Shutdown (player); // on error, shutdown the engine
  657.       }
  658.  
  659.       should_initialize = false; // remember this is no longer to be done (until the next call to PlayerEngine_Init())
  660.    }
  661.  
  662.    return; // finished
  663. }
  664.  
  665.  
  666. static wchar_t *Move_BuildString (boardmove_t *move)
  667. {
  668.    // helper function to build a move string to send to the engine from a particular board move. NOT THREAD SAFE.
  669.  
  670.    static wchar_t output_string[8];
  671.  
  672.    // construct the four first characters
  673.    swprintf_s (output_string, WCHAR_SIZEOF (output_string), L"%c%c%c%c",
  674.                L'a' + move->source[1], L'1' + move->source[0],
  675.                L'a' + move->target[1], L'1' + move->target[0]);
  676.  
  677.    // append any eventual promotion
  678.    if (move->promotion_type == PART_ROOK)
  679.       wcscat_s  (output_string, WCHAR_SIZEOF (output_string), L"r");
  680.    else if (move->promotion_type == PART_KNIGHT)
  681.       wcscat_s  (output_string, WCHAR_SIZEOF (output_string), L"n");
  682.    else if (move->promotion_type == PART_BISHOP)
  683.       wcscat_s  (output_string, WCHAR_SIZEOF (output_string), L"b");
  684.    else if (move->promotion_type == PART_QUEEN)
  685.       wcscat_s  (output_string, WCHAR_SIZEOF (output_string), L"q");
  686.  
  687.    return (output_string); // finished, return the move string
  688. }
  689.