#include "mersenne.h"
#include "movegen.h"
+using namespace std;
////
//// Global variables
const int EntrySize = 16;
- /// Random numbers from PolyGlot, used to compute book hash keys.
+ /// Random numbers from PolyGlot, used to compute book hash keys
const uint64_t Random64[781] = {
0x9D39247E33776D41ULL, 0x2AF7398005AAA5C7ULL, 0x44DB015024623547ULL,
uint64_t book_castle_key(const Position& pos);
uint64_t book_ep_key(const Position& pos);
uint64_t book_color_key(const Position& pos);
-
- uint16_t read_integer16(std::ifstream& file);
- uint64_t read_integer64(std::ifstream& file);
- uint64_t read_integer(std::ifstream& file, int size);
}
////
-/// Constructor
+/// Destructor. Be sure file is closed before we leave.
+
+Book::~Book() {
-Book::Book() : bookSize(0) {}
+ close();
+}
/// Book::open() opens a book file with a given file name
-void Book::open(const std::string& fName) {
+void Book::open(const string& fName) {
+
+ // Close old file before opening the new
+ close();
fileName = fName;
- bookFile.open(fileName.c_str(), std::ifstream::in | std::ifstream::binary);
- if (!bookFile.is_open())
+ ifstream::open(fileName.c_str(), ifstream::in | ifstream::binary);
+ if (!is_open())
return;
- // get the book size in number of entries
- bookFile.seekg(0, std::ios::end);
- bookSize = bookFile.tellg() / EntrySize;
- bookFile.seekg(0, std::ios::beg);
+ // Get the book size in number of entries
+ seekg(0, ios::end);
+ bookSize = tellg() / EntrySize;
+ seekg(0, ios::beg);
- if (!bookFile.good())
+ if (!good())
{
- std::cerr << "Failed to open book file " << fileName << std::endl;
- bookFile.close();
+ cerr << "Failed to open book file " << fileName << endl;
exit(EXIT_FAILURE);
}
}
-/// Book::close() closes the currently open book file
+/// 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.
void Book::close() {
- if (bookFile.is_open())
- bookFile.close();
-}
-
-
-/// Book::is_open() tests whether a book file has been opened.
-
-bool Book::is_open() const {
-
- return bookFile.is_open() && bookSize != 0;
+ if (is_open())
+ ifstream::close();
}
/// Book::file_name() returns the file name of the currently active book,
/// or the empty string if no book is open.
-const std::string Book::file_name() const {
+const string Book::file_name() const {
return is_open() ? fileName : "";
}
/// Book::get_move() gets a book move for a given position. Returns
/// MOVE_NONE if no book move is found.
-Move Book::get_move(const Position& pos) const {
+Move Book::get_move(const Position& pos) {
- if (!is_open())
+ if (!is_open() || bookSize == 0)
return MOVE_NONE;
int bookMove = 0, scoresSum = 0;
BookEntry entry;
// Choose a book move among the possible moves for the given position
- for (int i = find_key(key); i < bookSize; i++)
+ for (int idx = find_key(key); idx < bookSize; idx++)
{
- read_entry(entry, i);
+ read_entry(entry, idx);
if (entry.key != key)
break;
/// entry with the same key as the input is returned. When the key is not
/// found in the book file, bookSize is returned.
-int Book::find_key(uint64_t key) const {
+int Book::find_key(uint64_t key) {
int left, right, mid;
BookEntry entry;
assert(left <= right);
- while(left < right)
+ while (left < right)
{
mid = (left + right) / 2;
else
left = mid + 1;
}
+
assert(left == right);
read_entry(entry, left);
/// input, and looks up the opening book entry at the given index in the book
/// file. The book entry is copied to the first input parameter.
-void Book::read_entry(BookEntry& entry, int n) const {
+void Book::read_entry(BookEntry& entry, int idx) {
- assert(n >= 0 && n < bookSize);
+ assert(idx >= 0 && idx < bookSize);
assert(is_open());
- bookFile.seekg(n * EntrySize, std::ios_base::beg);
- if (!bookFile.good())
+ seekg(idx * EntrySize, ios_base::beg);
+ *this >> entry;
+ if (!good())
{
- std::cerr << "Failed to read book entry at index " << n << std::endl;
- bookFile.close();
+ cerr << "Failed to read book entry at index " << idx << endl;
exit(EXIT_FAILURE);
}
- entry.key = read_integer64(bookFile);
- entry.move = read_integer16(bookFile);
- entry.count = read_integer16(bookFile);
- entry.n = read_integer16(bookFile);
- entry.sum = read_integer16(bookFile);
+}
+
+
+/// Book::read_integer() reads size chars from the file stream
+/// and converts them in an integer number.
+
+uint64_t Book::read_integer(int size) {
+
+ char buf[8];
+ read(buf, size);
+
+ // Numbers are stored on disk as a binary byte stream
+ uint64_t n = 0ULL;
+ for (int i = 0; i < size; i++)
+ n = (n << 8) + (unsigned char)buf[i];
+
+ return n;
}
{
Bitboard b = pos.pieces_of_color(c);
- while (b != EmptyBoardBB)
+ while (b)
{
Square s = pop_1st_bit(&b);
Piece p = pos.piece_on(s);
result ^= book_piece_key(p, s);
}
}
-
result ^= book_castle_key(pos);
result ^= book_ep_key(pos);
result ^= book_color_key(pos);
uint64_t book_color_key(const Position& pos) {
return (pos.side_to_move() == WHITE ? Random64[RandomTurn] : 0ULL);
}
-
-
- uint16_t read_integer16(std::ifstream& file) {
-
- uint64_t n = read_integer(file, 2);
- assert(n == (uint16_t)n);
- return (uint16_t)n;
- }
-
-
- uint64_t read_integer64(std::ifstream& file) {
-
- return read_integer(file, 8);
- }
-
-
- uint64_t read_integer(std::ifstream& file, int size) {
-
- char buf[8];
- file.read(buf, size);
-
- if (!file.good())
- {
- std::cerr << "Failed to read " << size << " bytes from book file" << std::endl;
- file.close();
- exit(EXIT_FAILURE);
- }
-
- // Numbers are stored on disk in big endian format
- uint64_t n = 0ULL;
- for (int i = 0; i < size; i++)
- n = (n << 8) + (unsigned char)buf[i];
-
- return n;
- }
}
projects / stockfish / blobdiff