Don't access std::cout from Position::print()

Let the caller to decide where to redirect (cout or cerr) the
ASCII representation of the position. Rename the function to
reflect this.

Renamed also from_fen() and to_fen() to set() and fen() respectively.

No functional change.

src/benchmark.cpp

@@ -89,7 +89,7 @@ void benchmark(const Position& current, istream& is) {
       fens.assign(Defaults, Defaults + 16);
 
   else if (fenFile == "current")
-      fens.push_back(current.to_fen());
+      fens.push_back(current.fen());
 
   else
   {

src/position.cpp

@@ -172,11 +172,11 @@ Position& Position::operator=(const Position& pos) {
 }
 
 
-/// Position::from_fen() initializes the position object with the given FEN
+/// Position::set() initializes the position object with the given FEN string.
-/// string. This function is not very robust - make sure that input FENs are
+/// This function is not very robust - make sure that input FENs are correct,
-/// correct (this is assumed to be the responsibility of the GUI).
+/// this is assumed to be the responsibility of the GUI.
 
-void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) {
+void Position::set(const string& fenStr, bool isChess960, Thread* th) {
 /*
    A FEN string defines a particular position using only the ASCII character set.
 
@@ -214,13 +214,13 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) {
   char col, row, token;
   size_t p;
   Square sq = SQ_A8;
-  std::istringstream fen(fenStr);
+  std::istringstream ss(fenStr);
 
   clear();
-  fen >> std::noskipws;
+  ss >> std::noskipws;
 
   // 1. Piece placement
-  while ((fen >> token) && !isspace(token))
+  while ((ss >> token) && !isspace(token))
   {
       if (isdigit(token))
           sq += Square(token - '0'); // Advance the given number of files
@@ -236,16 +236,16 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) {
   }
 
   // 2. Active color
-  fen >> token;
+  ss >> token;
   sideToMove = (token == 'w' ? WHITE : BLACK);
-  fen >> token;
+  ss >> token;
 
   // 3. Castling availability. Compatible with 3 standards: Normal FEN standard,
   // Shredder-FEN that uses the letters of the columns on which the rooks began
   // the game instead of KQkq and also X-FEN standard that, in case of Chess960,
   // if an inner rook is associated with the castling right, the castling tag is
   // replaced by the file letter of the involved rook, as for the Shredder-FEN.
-  while ((fen >> token) && !isspace(token))
+  while ((ss >> token) && !isspace(token))
   {
       Square rsq;
       Color c = islower(token) ? BLACK : WHITE;
@@ -268,8 +268,8 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) {
   }
 
   // 4. En passant square. Ignore if no pawn capture is possible
-  if (   ((fen >> col) && (col >= 'a' && col <= 'h'))
+  if (   ((ss >> col) && (col >= 'a' && col <= 'h'))
-      && ((fen >> row) && (row == '3' || row == '6')))
+      && ((ss >> row) && (row == '3' || row == '6')))
   {
       st->epSquare = File(col - 'a') | Rank(row - '1');
 
@@ -278,7 +278,7 @@ void Position::from_fen(const string& fenStr, bool isChess960, Thread* th) {
   }
 
   // 5-6. Halfmove clock and fullmove number
-  fen >> std::skipws >> st->rule50 >> startPosPly;
+  ss >> std::skipws >> st->rule50 >> startPosPly;
 
   // Convert from fullmove starting from 1 to ply starting from 0,
   // handle also common incorrect FEN with fullmove = 0.
@@ -325,12 +325,12 @@ void Position::set_castle_right(Color c, Square rfrom) {
 }
 
 
-/// Position::to_fen() returns a FEN representation of the position. In case
+/// Position::fen() returns a FEN representation of the position. In case
 /// of Chess960 the Shredder-FEN notation is used. Mainly a debugging function.
 
-const string Position::to_fen() const {
+const string Position::fen() const {
 
-  std::ostringstream fen;
+  std::ostringstream ss;
   Square sq;
   int emptyCnt;
 
@@ -348,48 +348,48 @@ const string Position::to_fen() const {
           {
               if (emptyCnt > 0)
               {
-                  fen << emptyCnt;
+                  ss << emptyCnt;
                   emptyCnt = 0;
               }
-              fen << PieceToChar[piece_on(sq)];
+              ss << PieceToChar[piece_on(sq)];
           }
       }
 
       if (emptyCnt > 0)
-          fen << emptyCnt;
+          ss << emptyCnt;
 
       if (rank > RANK_1)
-          fen << '/';
+          ss << '/';
   }
 
-  fen << (sideToMove == WHITE ? " w " : " b ");
+  ss << (sideToMove == WHITE ? " w " : " b ");
 
   if (can_castle(WHITE_OO))
-      fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, KING_SIDE))))) : 'K');
+      ss << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, KING_SIDE))))) : 'K');
 
   if (can_castle(WHITE_OOO))
-      fen << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, QUEEN_SIDE))))) : 'Q');
+      ss << (chess960 ? char(toupper(file_to_char(file_of(castle_rook_square(WHITE, QUEEN_SIDE))))) : 'Q');
 
   if (can_castle(BLACK_OO))
-      fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, KING_SIDE))) : 'k');
+      ss << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, KING_SIDE))) : 'k');
 
   if (can_castle(BLACK_OOO))
-      fen << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, QUEEN_SIDE))) : 'q');
+      ss << (chess960 ? file_to_char(file_of(castle_rook_square(BLACK, QUEEN_SIDE))) : 'q');
 
   if (st->castleRights == CASTLES_NONE)
-      fen << '-';
+      ss << '-';
 
-  fen << (ep_square() == SQ_NONE ? " - " : " " + square_to_string(ep_square()) + " ")
+  ss << (ep_square() == SQ_NONE ? " - " : " " + square_to_string(ep_square()) + " ")
       << st->rule50 << " " << 1 + (startPosPly - int(sideToMove == BLACK)) / 2;
 
-  return fen.str();
+  return ss.str();
 }
 
 
-/// Position::print() prints an ASCII representation of the position to
+/// Position::pretty() returns an ASCII representation of the position to be
-/// the standard output. If a move is given then also the san is printed.
+/// printed to the standard output together with the move's san notation.
 
-void Position::print(Move move) const {
+const string Position::pretty(Move move) const {
 
   const string dottedLine =            "\n+---+---+---+---+---+---+---+---+";
   const string twoRows =  dottedLine + "\n|   | . |   | . |   | . |   | . |"
@@ -397,17 +397,18 @@ void Position::print(Move move) const {
 
   string brd = twoRows + twoRows + twoRows + twoRows + dottedLine;
 
-  sync_cout;
+  std::ostringstream ss;
 
   if (move)
-      cout << "\nMove is: " << (sideToMove == BLACK ? ".." : "")
+      ss << "\nMove is: " << (sideToMove == BLACK ? ".." : "")
-           << move_to_san(*const_cast<Position*>(this), move);
+         << move_to_san(*const_cast<Position*>(this), move);
 
   for (Square sq = SQ_A1; sq <= SQ_H8; sq++)
       if (piece_on(sq) != NO_PIECE)
           brd[513 - 68*rank_of(sq) + 4*file_of(sq)] = PieceToChar[piece_on(sq)];
 
-  cout << brd << "\nFen is: " << to_fen() << "\nKey is: " << st->key << sync_endl;
+  ss << brd << "\nFen is: " << fen() << "\nKey is: " << st->key;
+  return ss.str();
 }
 
 

src/position.h

@@ -93,13 +93,13 @@ class Position {
 public:
   Position() {}
   Position(const Position& p, Thread* t) { *this = p; thisThread = t; }
-  Position(const std::string& f, bool c960, Thread* t) { from_fen(f, c960, t); }
+  Position(const std::string& f, bool c960, Thread* t) { set(f, c960, t); }
   Position& operator=(const Position&);
 
   // Text input/output
-  void from_fen(const std::string& fen, bool isChess960, Thread* th);
+  void set(const std::string& fen, bool isChess960, Thread* th);
-  const std::string to_fen() const;
+  const std::string fen() const;
-  void print(Move m = MOVE_NONE) const;
+  const std::string pretty(Move m = MOVE_NONE) const;
 
   // Position representation
   Bitboard pieces() const;

src/search.cpp

@@ -218,7 +218,7 @@ void Search::think() {
   if (Options["Use Search Log"])
   {
       Log log(Options["Search Log Filename"]);
-      log << "\nSearching: "  << RootPos.to_fen()
+      log << "\nSearching: "  << RootPos.fen()
           << "\ninfinite: "   << Limits.infinite
           << " ponder: "      << Limits.ponder
           << " time: "        << Limits.time[RootColor]

src/uci.cpp

@@ -113,9 +113,9 @@ void UCI::loop(const string& args) {
       else if (token == "go")         go(pos, is);
       else if (token == "position")   set_position(pos, is);
       else if (token == "setoption")  set_option(is);
-      else if (token == "d")          pos.print();
       else if (token == "flip")       pos.flip();
       else if (token == "bench")      benchmark(pos, is);
+      else if (token == "d")          sync_cout << pos.pretty() << sync_endl;
       else if (token == "isready")    sync_cout << "readyok" << sync_endl;
       else if (token == "eval")       sync_cout << Eval::trace(pos) << sync_endl;
       else
@@ -155,7 +155,7 @@ namespace {
     else
         return;
 
-    pos.from_fen(fen, Options["UCI_Chess960"], Threads.main_thread());
+    pos.set(fen, Options["UCI_Chess960"], Threads.main_thread());
     SetupStates = Search::StateStackPtr(new std::stack<StateInfo>());
 
     // Parse move list (if any)