X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fposition.cpp;h=f25ee276b9ef70787d221f9a0454a4388c396223;hb=9c8c0de538317f4270a62c6b525cad1ff8303d16;hp=7f0e1447d08bde86e81ee24781a260509e0da54c;hpb=155bed18f5224d401ddf5b4b71d93d8a8c379b3c;p=stockfish

diff --git a/src/position.cpp b/src/position.cpp
index 7f0e1447..f25ee276 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -129,7 +129,7 @@ void Position::detach() {
 /// string. This function is not very robust - make sure that input FENs are
 /// correct (this is assumed to be the responsibility of the GUI).
 
-void Position::from_fen(const string& fen, bool isChess960) {
+void Position::from_fen(const string& fenStr, bool isChess960) {
 /*
    A FEN string defines a particular position using only the ASCII character set.
 
@@ -161,13 +161,13 @@ void Position::from_fen(const string& fen, bool isChess960) {
   char col, row, token;
   size_t p;
   Square sq = SQ_A8;
-  std::istringstream ss(fen);
+  std::istringstream fen(fenStr);
 
   clear();
-  ss >> std::noskipws;
+  fen >> std::noskipws;
 
   // 1. Piece placement
-  while ((ss >> token) && !isspace(token))
+  while ((fen >> token) && !isspace(token))
   {
       if (token == '/')
           sq -= Square(16); // Jump back of 2 rows
@@ -183,17 +183,17 @@ void Position::from_fen(const string& fen, bool isChess960) {
   }
 
   // 2. Active color
-  ss >> token;
+  fen >> token;
   sideToMove = (token == 'w' ? WHITE : BLACK);
-  ss >> token;
+  fen >> token;
 
   // 3. Castling availability
-  while ((ss >> token) && !isspace(token))
+  while ((fen >> token) && !isspace(token))
       set_castling_rights(token);
 
   // 4. En passant square. Ignore if no pawn capture is possible
-  if (   ((ss >> col) && (col >= 'a' && col <= 'h'))
-      && ((ss >> row) && (row == '3' || row == '6')))
+  if (   ((fen >> col) && (col >= 'a' && col <= 'h'))
+      && ((fen >> row) && (row == '3' || row == '6')))
   {
       st->epSquare = make_square(File(col - 'a'), Rank(row - '1'));
       Color them = opposite_color(sideToMove);
@@ -203,7 +203,7 @@ void Position::from_fen(const string& fen, bool isChess960) {
   }
 
   // 5-6. Halfmove clock and fullmove number
-  ss >> std::skipws >> st->rule50 >> fullMoves;
+  fen >> std::skipws >> st->rule50 >> fullMoves;
 
   // Various initialisations
   chess960 = isChess960;
@@ -270,13 +270,13 @@ void Position::set_castling_rights(char token) {
 
 const string Position::to_fen() const {
 
-  string fen;
+  std::ostringstream fen;
   Square sq;
-  char emptyCnt;
+  int emptyCnt;
 
-  for (Rank rank = RANK_8; rank >= RANK_1; rank--, fen += '/')
+  for (Rank rank = RANK_8; rank >= RANK_1; rank--)
   {
-      emptyCnt = '0';
+      emptyCnt = 0;
 
       for (File file = FILE_A; file <= FILE_H; file++)
       {
@@ -284,40 +284,46 @@ const string Position::to_fen() const {
 
           if (!square_is_empty(sq))
           {
-              if (emptyCnt != '0')
+              if (emptyCnt)
               {
-                  fen += emptyCnt;
-                  emptyCnt = '0';
+                  fen << emptyCnt;
+                  emptyCnt = 0;
               }
-              fen += PieceToChar[piece_on(sq)];
-          } else
+              fen << PieceToChar[piece_on(sq)];
+          }
+          else
               emptyCnt++;
       }
 
-      if (emptyCnt != '0')
-          fen += emptyCnt;
+      if (emptyCnt)
+          fen << emptyCnt;
+
+      if (rank > RANK_1)
+          fen << '/';
   }
 
-  fen += (sideToMove == WHITE ? " w " : " b ");
+  fen << (sideToMove == WHITE ? " w " : " b ");
 
   if (st->castleRights != CASTLES_NONE)
   {
       if (can_castle(WHITE_OO))
-          fen += chess960 ? char(toupper(file_to_char(square_file(castle_rook_square(WHITE_OO))))) : 'K';
+          fen << (chess960 ? char(toupper(file_to_char(square_file(castle_rook_square(WHITE_OO))))) : 'K');
 
       if (can_castle(WHITE_OOO))
-          fen += chess960 ? char(toupper(file_to_char(square_file(castle_rook_square(WHITE_OOO))))) : 'Q';
+          fen << (chess960 ? char(toupper(file_to_char(square_file(castle_rook_square(WHITE_OOO))))) : 'Q');
 
       if (can_castle(BLACK_OO))
-          fen += chess960 ? file_to_char(square_file(castle_rook_square(BLACK_OO))) : 'k';
+          fen << (chess960 ? file_to_char(square_file(castle_rook_square(BLACK_OO))) : 'k');
 
       if (can_castle(BLACK_OOO))
-          fen += chess960 ? file_to_char(square_file(castle_rook_square(BLACK_OOO))) : 'q';
+          fen << (chess960 ? file_to_char(square_file(castle_rook_square(BLACK_OOO))) : 'q');
   } else
-      fen += '-';
+      fen << '-';
 
-  fen += (ep_square() == SQ_NONE ? " -" : " " + square_to_string(ep_square()));
-  return fen;
+  fen << (ep_square() == SQ_NONE ? " -" : " " + square_to_string(ep_square()))
+      << " " << st->rule50 << " " << fullMoves;
+
+  return fen.str();
 }
 
 
@@ -331,7 +337,7 @@ void Position::print(Move move) const {
   if (move)
   {
       Position p(*this, thread());
-      string dd = (piece_color(piece_on(move_from(move))) == BLACK ? ".." : "");
+      string dd = (sideToMove == BLACK ? ".." : "");
       cout << "\nMove is: " << dd << move_to_san(p, move);
   }
 
@@ -507,14 +513,14 @@ bool Position::pl_move_is_legal(Move m, Bitboard pinned) const {
   assert(piece_color(piece_on(from)) == us);
   assert(piece_on(king_square(us)) == make_piece(us, KING));
 
-  // En passant captures are a tricky special case. Because they are
-  // rather uncommon, we do it simply by testing whether the king is attacked
-  // after the move is made
+  // En passant captures are a tricky special case. Because they are rather
+  // uncommon, we do it simply by testing whether the king is attacked after
+  // the move is made.
   if (move_is_ep(m))
   {
       Color them = opposite_color(us);
       Square to = move_to(m);
-      Square capsq = make_square(square_file(to), square_rank(from));
+      Square capsq = to + pawn_push(them);
       Square ksq = king_square(us);
       Bitboard b = occupied_squares();
 
@@ -924,7 +930,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
       // Set en passant square, only if moved pawn can be captured
       if ((to ^ from) == 16)
       {
-          if (attacks_from<PAWN>(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them))
+          if (attacks_from<PAWN>(from + pawn_push(us), us) & pieces(PAWN, them))
           {
               st->epSquare = Square((int(from) + int(to)) / 2);
               key ^= zobEp[st->epSquare];
@@ -1033,7 +1039,7 @@ void Position::do_capture_move(Key& key, PieceType capture, Color them, Square t
     {
         if (ep) // en passant ?
         {
-            capsq = (them == BLACK)? (to - DELTA_N) : (to - DELTA_S);
+            capsq = to + pawn_push(them);
 
             assert(to == st->epSquare);
             assert(relative_rank(opposite_color(them), to) == RANK_6);
@@ -1256,7 +1262,7 @@ void Position::undo_move(Move m) {
       Square capsq = to;
 
       if (ep)
-          capsq = (us == WHITE)? (to - DELTA_N) : (to - DELTA_S);
+          capsq = to - pawn_push(us);
 
       assert(st->capturedType != KING);
       assert(!ep || square_is_empty(capsq));
@@ -1461,7 +1467,7 @@ int Position::see(Move m) const {
   // Handle en passant moves
   if (st->epSquare == to && piece_type(piece_on(from)) == PAWN)
   {
-      Square capQq = (side_to_move() == WHITE ? to - DELTA_N : to - DELTA_S);
+      Square capQq = to - pawn_push(side_to_move());
 
       assert(capturedType == PIECE_TYPE_NONE);
       assert(piece_type(piece_on(capQq)) == PAWN);