Do not return unproven mate scores from null move search

[stockfish] / src / book.cpp

diff --git a/src/book.cpp b/src/book.cpp
index c6e1e436daa2f192e8c83afc7d03b2ca876bb524..20861988b24c906b1ba04c5788b6dc9014a553ca 100644 (file)
--- a/src/book.cpp
+++ b/src/book.cpp
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008 Marco Costalba
+  Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -390,7 +390,7 @@ void Book::close() {
 /// Book::file_name() returns the file name of the currently active book,
 /// or the empty string if no book is open.
 
-const string Book::file_name() const {
+const string Book::file_name() { // Not const to compile on HP-UX 11.X
 
   return is_open() ? fileName : "";
 }
@@ -429,11 +429,11 @@ Move Book::get_move(const Position& pos) {
   if (!bookMove)
       return MOVE_NONE;
 
-  MoveStack moves[256];
-  int n = generate_legal_moves(pos, moves);
-  for (int j = 0; j < n; j++)
-      if ((int(moves[j].move) & 07777) == bookMove)
-          return moves[j].move;
+  MoveStack mlist[256];
+  MoveStack* last = generate_moves(pos, mlist);
+  for (MoveStack* cur = mlist; cur != last; cur++)
+      if ((int(cur->move) & 07777) == bookMove)
+          return cur->move;
 
   return MOVE_NONE;
 }