Rename getters functions removing 'get_' prefix

[stockfish] / src / book.cpp

diff --git a/src/book.cpp b/src/book.cpp
index ed5cba4b0eb208b7b3ae3eff52226fe0013c5c3b..494c9c1121cfca0af4410ab249d7bd1c0b5e6456 100644 (file)
--- a/src/book.cpp
+++ b/src/book.cpp
@@ -28,6 +28,7 @@
 #include <iostream>
 
 #include "book.h"
+#include "misc.h"
 #include "movegen.h"
 
 using namespace std;
@@ -335,7 +336,7 @@ namespace {
         result ^= ZobCastle[3];
 
     if (pos.ep_square() != SQ_NONE)
-        result ^= ZobEnPassant[square_file(pos.ep_square())];
+        result ^= ZobEnPassant[file_of(pos.ep_square())];
 
     if (pos.side_to_move() == WHITE)
         result ^= ZobTurn[0];
@@ -348,7 +349,7 @@ namespace {
 /// Book c'tor. Make random number generation less deterministic, for book moves
 Book::Book() : bookSize(0) {
 
-  for (int i = abs(get_system_time() % 10000); i > 0; i--)
+  for (int i = abs(system_time() % 10000); i > 0; i--)
       RKiss.rand<unsigned>();
 }
 
@@ -361,8 +362,8 @@ Book::~Book() {
 }
 
 
-/// Book::close() closes the file only if it is open, otherwise
-/// we can end up in a little mess due to how std::ifstream works.
+/// Book::close() closes the file only if it is open, otherwise the call fails
+/// and the failbit internal state flag is set.
 
 void Book::close() {
 
@@ -374,21 +375,20 @@ void Book::close() {
 }
 
 
-/// Book::open() opens a book file with a given file name
+/// Book::open() opens a book file with a given name
 
 void Book::open(const string& fileName) {
 
   // Close old file before opening the new
   close();
 
-  bookFile.open(fileName.c_str(), ifstream::in | ifstream::binary);
+  bookFile.open(fileName.c_str(), ifstream::in | ifstream::binary |ios::ate);
 
   // Silently return when asked to open a non-exsistent file
   if (!bookFile.is_open())
       return;
 
-  // Get the book size in number of entries
-  bookFile.seekg(0, ios::end);
+  // Get the book size in number of entries, we are already at the file end
   bookSize = long(bookFile.tellg()) / sizeof(BookEntry);
 
   if (!bookFile.good())
@@ -402,44 +402,34 @@ void Book::open(const string& fileName) {
 }
 
 
-/// Book::get_move() gets a book move for a given position. Returns
-/// MOVE_NONE if no book move is found. If findBestMove is true then
-/// return always the highest rated book move.
+/// Book::probe() gets a book move for a given position. Returns MOVE_NONE
+/// if no book move is found. If findBest is true then returns always the
+/// highest rated move otherwise chooses randomly based on the move score.
 
-Move Book::get_move(const Position& pos, bool findBestMove) {
+Move Book::probe(const Position& pos, bool findBest) {
 
   if (!bookSize || !bookFile.is_open())
       return MOVE_NONE;
 
   BookEntry entry;
-  int bookMove = MOVE_NONE;
-  unsigned score, scoresSum = 0, bestScore = 0;
+  unsigned scoresSum = 0, bestScore = 0, bookMove = 0;
   uint64_t key = book_key(pos);
+  int idx = first_entry(key) - 1;
 
   // Choose a book move among the possible moves for the given position
-  for (int idx = first_entry(key); idx < bookSize; idx++)
+  while (++idx < bookSize && (entry = read_entry(idx), entry.key == key))
   {
-      entry = read_entry(idx);
-
-      if (entry.key != key)
-          break;
-
-      score = entry.count;
-
-      if (!findBestMove)
-      {
-          // Choose book move according to its score. If a move has a very
-          // high score it has higher probability to be choosen than a move
-          // with lower score. Note that first entry is always chosen.
-          scoresSum += score;
-          if (RKiss.rand<unsigned>() % scoresSum < score)
-              bookMove = entry.move;
-      }
-      else if (score > bestScore)
-      {
-          bestScore = score;
+      scoresSum += entry.count;
+
+      // Choose book move according to its score. If a move has a very
+      // high score it has higher probability to be choosen than a move
+      // with lower score. Note that first entry is always chosen.
+      if (   RKiss.rand<unsigned>() % scoresSum < entry.count
+          || (findBest && entry.count > bestScore))
           bookMove = entry.move;
-      }
+
+      if (entry.count > bestScore)
+          bestScore = entry.count;
   }
 
   if (!bookMove)
@@ -455,18 +445,16 @@ Move Book::get_move(const Position& pos, bool findBestMove) {
   // book move is a promotion we have to convert to our representation, in
   // all other cases we can directly compare with a Move after having
   // masked out special Move's flags that are not supported by PolyGlot.
-  int p = (bookMove >> 12) & 7;
-
-  if (p)
-      bookMove = int(make_promotion_move(move_from(Move(bookMove)),
-                 move_to(Move(bookMove)), PieceType(p + 1)));
+  int promotion = (bookMove >> 12) & 7;
 
-  // Verify the book move (if any) is legal
-  MoveStack mlist[MAX_MOVES];
-  MoveStack* last = generate<MV_LEGAL>(pos, mlist);
-  for (MoveStack* cur = mlist; cur != last; cur++)
-      if ((int(cur->move) & ~(3 << 14)) == bookMove) // Mask out special flags
-          return cur->move;
+  if (promotion)
+      bookMove = make_promotion_move(move_from(Move(bookMove)),
+                                     move_to(Move(bookMove)),
+                                     PieceType(promotion + 1));
+  // Verify the book move is legal
+  for (MoveList<MV_LEGAL> ml(pos); !ml.end(); ++ml)
+      if (unsigned(ml.move() & ~(3 << 14)) == bookMove) // Mask out special flags
+          return ml.move();
 
   return MOVE_NONE;
 }
@@ -513,7 +501,7 @@ Book& Book::operator>>(T& n) {
   n = 0;
 
   for (size_t i = 0; i < sizeof(T); i++)
-      n = (n << 8) + (T)bookFile.get();
+      n = T((n << 8) + bookFile.get());
 
   return *this;
 }