Suppress testing for availability in bughouse drops

Give up on testing legality of bughouse drop moves; this only causes problems,
because the move list sent by the ICS is not accompanied by holdings updates.
So XBoard parses it thinking the holdings are empty, making every drop move
an ImpossibleMove. Bughouse can only be played on ICS, and we might as well
trust the ICS that it will only pass us legal moves. A user should not be
able to enter illegal drops; unavailable pieces cannot be grabbed from the
holdings, and typing is diverted to the ICS directly (which would reject the
illegal drop without XBoard even knowing about it).
  Also improve switching to bh/zh, based on drop move in initial board.

diff --git a/backend.c b/backend.c
index 265a55c..bc25c5f 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -2446,6 +2446,7 @@ VariantSwitch (Board board, VariantClass newVariant)
           board[i][j+newHoldingsWidth-gameInfo.holdingsWidth] =
             board[i][j];
      }
+     board[HOLDINGS_SET] = 0;
      gameInfo.boardWidth  = newWidth;
      gameInfo.boardHeight = newHeight;
      gameInfo.holdingsWidth = newHoldingsWidth;
@@ -4313,6 +4314,7 @@ ParseBoard12 (char *string)
     }
 
    if (gameInfo.boardHeight != ranks || gameInfo.boardWidth != files ||
+                                       move_str[1] == '@' && !gameInfo.holdingsWidth ||
                                        weird && (int)gameInfo.variant < (int)VariantShogi) {
      /* [HGM] We seem to have switched variant unexpectedly
       * Try to guess new variant from board size
@@ -4322,7 +4324,8 @@ ParseBoard12 (char *string)
          if(ranks == 10 && files == 9) newVariant = VariantXiangqi; else
          if(ranks == 8 && files == 12) newVariant = VariantCourier; else
          if(ranks == 9 && files == 9)  newVariant = VariantShogi; else
-         if(!weird) newVariant = VariantNormal;
+         if(ranks == 10 && files == 10) newVariant = VariantGrand; else
+         if(!weird) newVariant = move_str[1] == '@' ? VariantCrazyhouse : VariantNormal;
           VariantSwitch(boards[currentMove], newVariant); /* temp guess */
          /* Get a move list just to see the header, which
             will tell us whether this is really bug or zh */

diff --git a/moves.c b/moves.c
index 1c4fe51..a458a84 100644 (file)
--- a/moves.c
+++ b/moves.c
@@ -1053,7 +1053,8 @@ LegalDrop (Board board, int flags, ChessSquare piece, int rt, int ft)
 if(appData.debugMode) fprintf(debugFP, "LegalDrop: %d @ %d,%d)\n", piece, ft, rt);
     if(board[rt][ft] != EmptySquare) return ImpossibleMove; // must drop to empty square
     n = PieceToNumber(piece);
-    if(gameInfo.holdingsWidth == 0 || (flags & F_WHITE_ON_MOVE ? board[n][BOARD_WIDTH-1] : board[BOARD_HEIGHT-1-n][0]) != piece)
+    if((gameInfo.holdingsWidth == 0 || (flags & F_WHITE_ON_MOVE ? board[n][BOARD_WIDTH-1] : board[BOARD_HEIGHT-1-n][0]) != piece)
+       && gameInfo.variant != VariantBughouse) // in bughouse we don't check for availability, because ICS doesn't always tell us
         return ImpossibleMove; // piece not available
     if(gameInfo.variant == VariantShogi) { // in Shogi lots of drops are forbidden!
         if((piece == WhitePawn || piece == WhiteQueen) && rt == BOARD_HEIGHT-1 ||