X-Git-Url: http://winboard.nl/cgi-bin?a=blobdiff_plain;f=backend.c;h=084c42c5bf737b03d2bc4b910a20388c4321fc42;hb=e6e38912837a4fe2464356408d10dee950b3121c;hp=a9abaa853b7239cc626f103cdb24d7e6ecb5eda0;hpb=496a28be421660ca3fc07884f422f46b474c309a;p=xboard.git

diff --git a/backend.c b/backend.c
index a9abaa8..084c42c 100644
--- a/backend.c
+++ b/backend.c
@@ -5,7 +5,7 @@
  * Massachusetts.
  *
  * Enhancements Copyright 1992-2001, 2002, 2003, 2004, 2005, 2006,
- * 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
+ * 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014 Free Software Foundation, Inc.
  *
  * Enhancements Copyright 2005 Alessandro Scotti
  *
@@ -55,14 +55,32 @@
 #ifdef WIN32
 #include <windows.h>
 
-int flock(int f, int code);
-#define LOCK_EX 2
-#define SLASH '\\'
+    int flock(int f, int code);
+#   define LOCK_EX 2
+#   define SLASH '\\'
+
+#   ifdef ARC_64BIT
+#       define EGBB_NAME "egbbdll64.dll"
+#   else
+#       define EGBB_NAME "egbbdll.dll"
+#   endif
 
 #else
 
-#include <sys/file.h>
-#define SLASH '/'
+#   include <sys/file.h>
+#   define SLASH '/'
+
+#   include <dlfcn.h>
+#   ifdef ARC_64BIT
+#       define EGBB_NAME "egbbso64.so"
+#   else
+#       define EGBB_NAME "egbbso.so"
+#   endif
+    // kludge to allow Windows code in back-end by converting it to corresponding Linux code 
+#   define CDECL
+#   define HMODULE void *
+#   define LoadLibrary(x) dlopen(x, RTLD_LAZY)
+#   define GetProcAddress dlsym
 
 #endif
 
@@ -845,6 +863,7 @@ InitEngine (ChessProgramState *cps, int n)
     /* [HGM] debug */
     cps->debug = FALSE;
 
+    cps->drawDepth = appData.drawDepth[n];
     cps->supportsNPS = UNKNOWN;
     cps->memSize = FALSE;
     cps->maxCores = FALSE;
@@ -1564,6 +1583,23 @@ InitBackEnd3 P((void))
     char buf[MSG_SIZ];
     int err, len;
 
+    if(!appData.icsActive && !appData.noChessProgram && !appData.matchMode &&                         // mode involves only first engine
+       !strcmp(appData.variant, "normal") &&                                                          // no explicit variant request
+        appData.NrRanks == -1 && appData.NrFiles == -1 && appData.holdingsSize == -1 &&               // no size overrides requested
+       !SupportedVariant(first.variants, VariantNormal, 8, 8, 0, first.protocolVersion, "") &&        // but 'normal' won't work with engine
+       !SupportedVariant(first.variants, VariantFischeRandom, 8, 8, 0, first.protocolVersion, "") ) { // nor will Chess960
+	char c, *q = first.variants, *p = strchr(q, ',');
+	if(p) *p = NULLCHAR;
+	if(StringToVariant(q) != VariantUnknown) { // the engine can play a recognized variant, however
+	    int w, h, s;
+	    if(sscanf(q, "%dx%d+%d_%c", &w, &h, &s, &c) == 4) // get size overrides the engine needs with it (if any)
+		appData.NrFiles = w, appData.NrRanks = h, appData.holdingsSize = s, q = strchr(q, '_') + 1;
+	    ASSIGN(appData.variant, q); // fake user requested the first variant played by the engine
+	    Reset(TRUE, FALSE);         // and re-initialize
+	}
+	if(p) *p = ',';
+    }
+
     InitChessProgram(&first, startedFromSetupPosition);
 
     if(!appData.noChessProgram) {  /* [HGM] tidy: redo program version to use name from myname feature */
@@ -4796,7 +4832,7 @@ ParseBoard12 (char *string)
 	      default:
 		break;
 	      case MT_CHECK:
-                if(gameInfo.variant != VariantShogi)
+                if(!IS_SHOGI(gameInfo.variant))
                     strcat(parseList[moveNum - 1], "+");
 		break;
 	      case MT_CHECKMATE:
@@ -5313,20 +5349,24 @@ void
 Sweep (int step)
 {
     ChessSquare king = WhiteKing, pawn = WhitePawn, last = promoSweep;
+    static int toggleFlag;
     if(gameInfo.variant == VariantKnightmate) king = WhiteUnicorn;
     if(gameInfo.variant == VariantSuicide || gameInfo.variant == VariantGiveaway) king = EmptySquare;
     if(promoSweep >= BlackPawn) king = WHITE_TO_BLACK king, pawn = WHITE_TO_BLACK pawn;
     if(gameInfo.variant == VariantSpartan && pawn == BlackPawn) pawn = BlackLance, king = EmptySquare;
-    if(fromY != BOARD_HEIGHT-2 && fromY != 1) pawn = EmptySquare;
+    if(fromY != BOARD_HEIGHT-2 && fromY != 1 && gameInfo.variant != VariantChuChess) pawn = EmptySquare;
+    if(!step) toggleFlag = Partner(&last); // piece has shogi-promotion
     do {
-	if(step && !Partner(&promoSweep)) promoSweep -= step;
+	if(step && !(toggleFlag && Partner(&promoSweep))) promoSweep -= step;
 	if(promoSweep == EmptySquare) promoSweep = BlackPawn; // wrap
 	else if((int)promoSweep == -1) promoSweep = WhiteKing;
 	else if(promoSweep == BlackPawn && step < 0) promoSweep = WhitePawn;
 	else if(promoSweep == WhiteKing && step > 0) promoSweep = BlackKing;
 	if(!step) step = -1;
     } while(PieceToChar(promoSweep) == '.' || PieceToChar(promoSweep) == '~' || promoSweep == pawn ||
-	    appData.testLegality && (promoSweep == king || promoSweep == WhiteLion || promoSweep == BlackLion));
+	    !toggleFlag && PieceToChar(promoSweep) == '+' || // skip promoted versions of other
+	    appData.testLegality && (promoSweep == king || gameInfo.variant != VariantChuChess &&
+            (promoSweep == WhiteLion || promoSweep == BlackLion)));
     if(toX >= 0) {
 	int victim = boards[currentMove][toY][toX];
 	boards[currentMove][toY][toX] = promoSweep;
@@ -6457,7 +6497,7 @@ HasPromotionChoice (int fromX, int fromY, int toX, int toY, char *promoChoice, i
     /* [HGM] rewritten IsPromotion to only flag promotions that offer a choice */
     /* [HGM] add Shogi promotions */
     int promotionZoneSize=1, highestPromotingPiece = (int)WhitePawn;
-    ChessSquare piece;
+    ChessSquare piece, partner;
     ChessMove moveType;
     Boolean premove;
 
@@ -6532,7 +6572,11 @@ HasPromotionChoice (int fromX, int fromY, int toX, int toY, char *promoChoice, i
     // we either have a choice what to promote to, or (in Shogi) whether to promote
     if(gameInfo.variant == VariantShatranj || gameInfo.variant == VariantCourier ||
        gameInfo.variant == VariantMakruk || gameInfo.variant == VariantASEAN) {
-	*promoChoice = PieceToChar(BlackFerz);  // no choice
+	ChessSquare p=BlackFerz;  // no choice
+	while(p < EmptySquare) {  //but make sure we use piece that exists
+	    *promoChoice = PieceToChar(p++);
+	    if(*promoChoice != '.') break;
+	}
 	return FALSE;
     }
     // no sense asking what we must promote to if it is going to explode...
@@ -6542,8 +6586,9 @@ HasPromotionChoice (int fromX, int fromY, int toX, int toY, char *promoChoice, i
     }
     // give caller the default choice even if we will not make it
     *promoChoice = ToLower(PieceToChar(defaultPromoChoice));
-    if(IS_SHOGI(gameInfo.variant)) *promoChoice = (defaultPromoChoice == piece ? '=' : '+');
-    if(gameInfo.variant == VariantChuChess) *promoChoice = (piece == WhitePawn || piece == BlackPawn ? 'q' : '+');
+    partner = piece; // pieces can promote if the pieceToCharTable says so
+    if(IS_SHOGI(gameInfo.variant)) *promoChoice = (defaultPromoChoice == piece && sweepSelect ? '=' : '+'); // obsolete?
+    else if(Partner(&partner))     *promoChoice = (defaultPromoChoice == piece && sweepSelect ? NULLCHAR : '+');
     if(        sweepSelect && gameInfo.variant != VariantGreat
 			   && gameInfo.variant != VariantGrand
 			   && gameInfo.variant != VariantSuper) return FALSE;
@@ -6555,6 +6600,7 @@ HasPromotionChoice (int fromX, int fromY, int toX, int toY, char *promoChoice, i
     if(appData.testLegality && !premove) {
 	moveType = LegalityTest(boards[currentMove], PosFlags(currentMove),
 			fromY, fromX, toY, toX, IS_SHOGI(gameInfo.variant) || gameInfo.variant == VariantChuChess ? '+' : NULLCHAR);
+        if(moveType == IllegalMove) *promoChoice = NULLCHAR; // could be the fact we promoted was illegal
 	if(moveType != WhitePromotion && moveType  != BlackPromotion)
 	    return FALSE;
     }
@@ -7169,12 +7215,15 @@ Mark (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VO
     else if(flags & F_MANDATORY_CAPTURE && board[rt][ft] != EmptySquare) (*m)[rt][ft] = 3;
 }
 
+static int hoverSavedValid;
+
 void
 MarkTargetSquares (int clear)
 {
   int x, y, sum=0;
   if(clear) { // no reason to ever suppress clearing
-    for(x=0; x<BOARD_WIDTH; x++) for(y=0; y<BOARD_HEIGHT; y++) sum += marker[y][x], marker[y][x] = baseMarker[y][x] = 0;
+    for(x=0; x<BOARD_WIDTH; x++) for(y=0; y<BOARD_HEIGHT; y++) sum += marker[y][x], marker[y][x] = 0;
+    hoverSavedValid = 0;
     if(!sum) return; // nothing was cleared,no redraw needed
   } else {
     int capt = 0;
@@ -7209,14 +7258,15 @@ ChessSquare gatingPiece = EmptySquare; // exported to front-end, for dragging
 int
 CanPromote (ChessSquare piece, int y)
 {
+        int zone = (gameInfo.variant == VariantChuChess ? 3 : 1);
 	if(gameMode == EditPosition) return FALSE; // no promotions when editing position
 	// some variants have fixed promotion piece, no promotion at all, or another selection mechanism
 	if(IS_SHOGI(gameInfo.variant)          || gameInfo.variant == VariantXiangqi ||
 	   gameInfo.variant == VariantSuper    || gameInfo.variant == VariantGreat   ||
 	   gameInfo.variant == VariantShatranj || gameInfo.variant == VariantCourier ||
          gameInfo.variant == VariantMakruk   || gameInfo.variant == VariantASEAN) return FALSE;
-	return (piece == BlackPawn && y == 1 ||
-		piece == WhitePawn && y == BOARD_HEIGHT-2 ||
+	return (piece == BlackPawn && y <= zone ||
+		piece == WhitePawn && y >= BOARD_HEIGHT-1-zone ||
 		piece == BlackLance && y == 1 ||
 		piece == WhiteLance && y == BOARD_HEIGHT-2 );
 }
@@ -7230,11 +7280,13 @@ HoverEvent (int xPix, int yPix, int x, int y)
 	if(fromX != oldFromX || fromY != oldFromY)  oldX = oldY = -1; // kludge to fake entry on from-click
 	if(x == oldX && y == oldY) return; // only do something if we enter new square
 	oldFromX = fromX; oldFromY = fromY;
-	if(oldX == -1 && oldY == -1 && x == fromX && y == fromY) // record markings after from-change
+	if(oldX == -1 && oldY == -1 && x == fromX && y == fromY) { // record markings after from-change
 	  for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
 	    baseMarker[r][f] = marker[r][f], baseLegal[r][f] = legal[r][f];
-	else if(oldX != x || oldY != y) {
+	  hoverSavedValid = 1;
+	} else if(oldX != x || oldY != y) {
 	  // [HGM] lift: entered new to-square; redraw arrow, and inform engine
+	  if(hoverSavedValid) // don't restore markers that are supposed to be cleared
 	  for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
 	    marker[r][f] = baseMarker[r][f], legal[r][f] = baseLegal[r][f];
 	  if((marker[y][x] == 2 || marker[y][x] == 6) && legal[y][x]) {
@@ -7487,8 +7539,11 @@ LeftClick (ClickType clickType, int xPix, int yPix)
 	toY = y;
     }
 
+    piece = boards[currentMove][fromY][fromX];
+
     saveAnimate = appData.animate;
     if (clickType == Press) {
+	if(gameInfo.variant == VariantChuChess && piece != WhitePawn && piece != BlackPawn) defaultPromoChoice = piece;
 	if(gameMode == EditPosition && boards[currentMove][fromY][fromX] == EmptySquare) {
 	    // must be Edit Position mode with empty-square selected
 	    fromX = x; fromY = y; DragPieceBegin(xPix, yPix, FALSE); dragging = 1; // consider this a new attempt to drag
@@ -7504,9 +7559,8 @@ LeftClick (ClickType clickType, int xPix, int yPix)
 	if(marker[y][x] == 5) return; // [HGM] lion: to-click on cyan square; defer action to release
 	if(legal[y][x] == 2 || HasPromotionChoice(fromX, fromY, toX, toY, &promoChoice, FALSE)) {
 	  if(appData.sweepSelect) {
-	    ChessSquare piece = boards[currentMove][fromY][fromX];
 	    promoSweep = defaultPromoChoice;
-	    if(PieceToChar(CHUPROMOTED piece) == '+') promoSweep = CHUPROMOTED piece;
+	    if(gameInfo.variant != VariantChuChess && PieceToChar(CHUPROMOTED piece) == '+') promoSweep = CHUPROMOTED piece;
 	    selectFlag = 0; lastX = xPix; lastY = yPix;
 	    Sweep(0); // Pawn that is going to promote: preview promotion piece
 	    sweepSelecting = 1;
@@ -7522,7 +7576,7 @@ LeftClick (ClickType clickType, int xPix, int yPix)
 	    ClearHighlights();
 	}
     } else if(sweepSelecting) { // this must be the up-click corresponding to the down-click that started the sweep
-	sweepSelecting = 0;
+	sweepSelecting = 0; appData.animate = FALSE; // do not animate, a selected piece already on to-square
 	if (appData.animate || appData.highlightLastMove) {
 	    SetHighlights(fromX, fromY, toX, toY);
 	} else {
@@ -7538,6 +7592,7 @@ LeftClick (ClickType clickType, int xPix, int yPix)
 	    ClearHighlights();
 	}
 #endif
+	if(gameInfo.variant == VariantChuChess && piece != WhitePawn && piece != BlackPawn) defaultPromoChoice = piece;
 	if(marker[y][x] == 5) { // [HGM] lion: this was the release of a to-click or drag on a cyan square
 	  dragging *= 2;            // flag button-less dragging if we are dragging
 	  MarkTargetSquares(1);
@@ -7604,7 +7659,7 @@ LeftClick (ClickType clickType, int xPix, int yPix)
 	    DisplayMessage("Click in holdings to choose piece", "");
 	    return;
 	}
-	PromotionPopUp();
+	PromotionPopUp(promoChoice);
     } else {
 	int oldMove = currentMove;
 	UserMoveEvent(fromX, fromY, toX, toY, promoChoice);
@@ -7998,6 +8053,7 @@ Adjudicate (ChessProgramState *cps)
 	      case MT_NONE:
 	      default:
 		break;
+	      case MT_STEALMATE:
 	      case MT_STALEMATE:
 	      case MT_STAINMATE:
 		reason = "Xboard adjudication: Stalemate";
@@ -8236,11 +8292,66 @@ Adjudicate (ChessProgramState *cps)
 	return 0;
 }
 
+typedef int (CDECL *PPROBE_EGBB) (int player, int *piece, int *square);
+typedef int (CDECL *PLOAD_EGBB) (char *path, int cache_size, int load_options);
+static int egbbCode[] = { 6, 5, 4, 3, 2, 1 };
+
+static int
+BitbaseProbe ()
+{
+    int pieces[10], squares[10], cnt=0, r, f, res;
+    static int loaded;
+    static PPROBE_EGBB probeBB;
+    if(!appData.testLegality) return 10;
+    if(BOARD_HEIGHT != 8 || BOARD_RGHT-BOARD_LEFT != 8) return 12;
+    if(gameInfo.holdingsSize && gameInfo.variant != VariantSuper && gameInfo.variant != VariantSChess) return 12;
+    if(loaded == 2 && forwardMostMove < 2) loaded = 0; // retry on new game
+    for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) {
+	ChessSquare piece = boards[forwardMostMove][r][f];
+	int black = (piece >= BlackPawn);
+	int type = piece - black*BlackPawn;
+	if(piece == EmptySquare) continue;
+	if(type != WhiteKing && type > WhiteQueen) return 12; // unorthodox piece
+	if(type == WhiteKing) type = WhiteQueen + 1;
+	type = egbbCode[type];
+	squares[cnt] = r*(BOARD_RGHT - BOARD_LEFT) + f - BOARD_LEFT;
+        pieces[cnt] = type + black*6;
+	if(++cnt > 5) return 11;
+    }
+    pieces[cnt] = squares[cnt] = 0;
+    // probe EGBB
+    if(loaded == 2) return 13; // loading failed before
+    if(loaded == 0) {
+	loaded = 2; // prepare for failure
+	char *p, *path = strstr(appData.egtFormats, "scorpio:"), buf[MSG_SIZ];
+	HMODULE lib;
+	PLOAD_EGBB loadBB;
+	if(!path) return 13; // no egbb installed
+	strncpy(buf, path + 8, MSG_SIZ);
+	if(p = strchr(buf, ',')) *p = NULLCHAR; else p = buf + strlen(buf);
+	snprintf(p, MSG_SIZ - strlen(buf), "%c%s", SLASH, EGBB_NAME);
+	lib = LoadLibrary(buf);
+	if(!lib) { DisplayError(_("could not load EGBB library"), 0); return 13; }
+	loadBB = (PLOAD_EGBB) GetProcAddress(lib, "load_egbb_xmen");
+	probeBB = (PPROBE_EGBB) GetProcAddress(lib, "probe_egbb_xmen");
+	if(!loadBB || !probeBB) { DisplayError(_("wrong EGBB version"), 0); return 13; }
+	p[1] = NULLCHAR; loadBB(buf, 64*1028, 2); // 2 = SMART_LOAD
+	loaded = 1; // success!
+    }
+    res = probeBB(forwardMostMove & 1, pieces, squares);
+    return res > 0 ? 1 : res < 0 ? -1 : 0;
+}
+
 char *
 SendMoveToBookUser (int moveNr, ChessProgramState *cps, int initial)
 {   // [HGM] book: this routine intercepts moves to simulate book replies
     char *bookHit = NULL;
 
+    if(cps->drawDepth && BitbaseProbe() == 0) { // [HG} egbb: reduce depth in drawn position
+	char buf[MSG_SIZ];
+	snprintf(buf, MSG_SIZ, "sd %d\n", cps->drawDepth);
+	SendToProgram(buf, cps);
+    }
     //first determine if the incoming move brings opponent into his book
     if(appData.usePolyglotBook && (cps == &first ? !appData.firstHasOwnBookUCI : !appData.secondHasOwnBookUCI))
 	bookHit = ProbeBook(moveNr+1, appData.polyglotBook); // returns move
@@ -9673,7 +9784,7 @@ ParseGameHistory (char *game)
 	  default:
 	    break;
 	  case MT_CHECK:
-            if(gameInfo.variant != VariantShogi)
+            if(!IS_SHOGI(gameInfo.variant))
                 strcat(parseList[boardIndex - 1], "+");
 	    break;
 	  case MT_CHECKMATE:
@@ -9810,7 +9921,7 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
         board[toY][toX+1] = board[fromY][BOARD_LEFT];
         board[fromY][BOARD_LEFT] = EmptySquare;
     } else if ((board[fromY][fromX] == WhitePawn && gameInfo.variant != VariantXiangqi ||
-                board[fromY][fromX] == WhiteLance && gameInfo.variant != VariantSuper && gameInfo.variant != VariantShogi)
+                board[fromY][fromX] == WhiteLance && gameInfo.variant != VariantSuper && gameInfo.variant != VariantChu)
                && toY >= BOARD_HEIGHT-promoRank && promoChar // defaulting to Q is done elsewhere
                ) {
 	/* white pawn promotion */
@@ -9871,7 +9982,7 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
 	board[fromY][0] = EmptySquare;
 	board[toY][2] = BlackRook;
     } else if ((board[fromY][fromX] == BlackPawn && gameInfo.variant != VariantXiangqi ||
-                board[fromY][fromX] == BlackLance && gameInfo.variant != VariantSuper && gameInfo.variant != VariantShogi)
+                board[fromY][fromX] == BlackLance && gameInfo.variant != VariantSuper && gameInfo.variant != VariantChu)
 	       && toY < promoRank && promoChar
                ) {
 	/* black pawn promotion */
@@ -9984,6 +10095,7 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
 	board[toY][toX] = EmptySquare;
       }
     }
+
     if(gameInfo.variant == VariantSChess && promoChar != NULLCHAR && promoChar != '=' && piece != WhitePawn && piece != BlackPawn) {
         board[fromY][fromX] = CharToPiece(piece < BlackPawn ? ToUpper(promoChar) : ToLower(promoChar)); // S-Chess gating
     } else
@@ -10114,7 +10226,7 @@ MakeMove (int fromX, int fromY, int toX, int toY, int promoChar)
       default:
 	break;
       case MT_CHECK:
-        if(gameInfo.variant != VariantShogi)
+        if(!IS_SHOGI(gameInfo.variant))
             strcat(parseList[forwardMostMove - 1], "+");
 	break;
       case MT_CHECKMATE:
@@ -10688,6 +10800,7 @@ SwapEngines (int n)
     SWAP(fenOverride, p)
     SWAP(NPS, h)
     SWAP(accumulateTC, h)
+    SWAP(drawDepth, h)
     SWAP(host, p)
 }
 
@@ -12083,22 +12196,40 @@ void
 PackMove (int fromX, int fromY, int toX, int toY, ChessSquare promoPiece)
 {
     int sq = fromX + (fromY<<4);
-    int piece = quickBoard[sq];
+    int piece = quickBoard[sq], rook;
     quickBoard[sq] = 0;
     moveDatabase[movePtr].to = pieceList[piece] = sq = toX + (toY<<4);
-    if(piece == pieceList[1] && fromY == toY && (toX > fromX+1 || toX < fromX-1) && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1) {
+    if(piece == pieceList[1] && fromY == toY) {
+      if((toX > fromX+1 || toX < fromX-1) && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1) {
 	int from = toX>fromX ? BOARD_RGHT-1 : BOARD_LEFT;
 	moveDatabase[movePtr++].piece = Q_WCASTL;
 	quickBoard[sq] = piece;
 	piece = quickBoard[from]; quickBoard[from] = 0;
 	moveDatabase[movePtr].to = pieceList[piece] = sq = toX>fromX ? sq-1 : sq+1;
+      } else if((rook = quickBoard[sq]) && pieceType[rook] == WhiteRook) { // FRC castling
+	quickBoard[sq] = 0; // remove Rook
+	moveDatabase[movePtr].to = sq = (toX>fromX ? BOARD_RGHT-2 : BOARD_LEFT+2); // King to-square
+	moveDatabase[movePtr++].piece = Q_WCASTL;
+	quickBoard[sq] = pieceList[1]; // put King
+	piece = rook;
+	moveDatabase[movePtr].to = pieceList[rook] = sq = toX>fromX ? sq-1 : sq+1;
+      }
     } else
-    if(piece == pieceList[2] && fromY == toY && (toX > fromX+1 || toX < fromX-1) && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1) {
+    if(piece == pieceList[2] && fromY == toY) {
+      if((toX > fromX+1 || toX < fromX-1) && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1) {
 	int from = (toX>fromX ? BOARD_RGHT-1 : BOARD_LEFT) + (BOARD_HEIGHT-1 <<4);
 	moveDatabase[movePtr++].piece = Q_BCASTL;
 	quickBoard[sq] = piece;
 	piece = quickBoard[from]; quickBoard[from] = 0;
 	moveDatabase[movePtr].to = pieceList[piece] = sq = toX>fromX ? sq-1 : sq+1;
+      } else if((rook = quickBoard[sq]) && pieceType[rook] == BlackRook) { // FRC castling
+	quickBoard[sq] = 0; // remove Rook
+	moveDatabase[movePtr].to = sq = (toX>fromX ? BOARD_RGHT-2 : BOARD_LEFT+2);
+	moveDatabase[movePtr++].piece = Q_BCASTL;
+	quickBoard[sq] = pieceList[2]; // put King
+	piece = rook;
+	moveDatabase[movePtr].to = pieceList[rook] = sq = toX>fromX ? sq-1 : sq+1;
+      }
     } else
     if(epOK && (pieceType[piece] == WhitePawn || pieceType[piece] == BlackPawn) && fromX != toX && quickBoard[sq] == 0) {
 	quickBoard[(fromY<<4)+toX] = 0;