Adapt gating legality test to holdingless case

The test in Disambiguate() to see if an indicated gating is legal
now is aware that in holdingless Seirawan gating takes place on the
second rank. It also reserves the test for RxK castling to the case
with holdings.

diff --git a/moves.c b/moves.c
index 2574fd0..032b6b0 100644 (file)
--- a/moves.c
+++ b/moves.c
@@ -2239,17 +2239,21 @@ Disambiguate (Board board, int flags, DisambiguateClosure *closure)
     if (c == 'x') c = NULLCHAR; // get rid of any 'x' (which should never happen?)
     if(gameInfo.variant == VariantSChess && c && c != '=' && closure->piece != WhitePawn && closure->piece != BlackPawn) {
         if(closure->piece < BlackPawn) { // white
-            if(closure->rf != 0) closure->kind = IllegalMove; // must be on back rank
-            if(!(board[VIRGIN][closure->ff] & VIRGIN_W)) closure->kind = IllegalMove; // non-virgin
+          if(closure->rf != !gameInfo.holdingsSize) closure->kind = IllegalMove; // must be on back rank
+          if(!(board[VIRGIN][closure->ff] & VIRGIN_W)) closure->kind = IllegalMove; // non-virgin
+          if(gameInfo.holdingsSize) {
             if(board[PieceToNumber(CharToPiece(ToUpper(c)))][BOARD_WIDTH-2] == 0) closure->kind = ImpossibleMove;// must be in stock
             if(closure->kind == WhiteHSideCastleFR && (closure->ff == BOARD_RGHT-2 || closure->ff == BOARD_RGHT-3)) closure->kind = ImpossibleMove;
             if(closure->kind == WhiteASideCastleFR && (closure->ff == BOARD_LEFT+2 || closure->ff == BOARD_LEFT+3)) closure->kind = ImpossibleMove;
+          }
         } else {
-            if(closure->rf != BOARD_HEIGHT-1) closure->kind = IllegalMove;
-            if(!(board[VIRGIN][closure->ff] & VIRGIN_B)) closure->kind = IllegalMove; // non-virgin
+          if(closure->rf != BOARD_HEIGHT-1-!gameInfo.holdingsSize) closure->kind = IllegalMove;
+          if(!(board[VIRGIN][closure->ff] & VIRGIN_B)) closure->kind = IllegalMove; // non-virgin
+          if(gameInfo.holdingsSize) {
             if(board[BOARD_HEIGHT-1-PieceToNumber(CharToPiece(ToLower(c)))][1] == 0) closure->kind = ImpossibleMove;
             if(closure->kind == BlackHSideCastleFR && (closure->ff == BOARD_RGHT-2 || closure->ff == BOARD_RGHT-3)) closure->kind = ImpossibleMove;
             if(closure->kind == BlackASideCastleFR && (closure->ff == BOARD_LEFT+2 || closure->ff == BOARD_LEFT+3)) closure->kind = ImpossibleMove;
+          }
         }
     } else
     if(gameInfo.variant == VariantChu) {