gnushogi/book.c

   1 /*
   2  * FILE: book.c
   3  *
   4  * ----------------------------------------------------------------------
   5  *
   6  * Copyright (c) 2012 Free Software Foundation
   7  *
   8  * GNU SHOGI is based on GNU CHESS
   9  *
  10  * This file is part of GNU SHOGI.
  11  *
  12  * GNU Shogi is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 3 of the License,
  15  * or (at your option) any later version.
  16  *
  17  * GNU Shogi is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with GNU Shogi; see the file COPYING. If not, see
  24  * <http://www.gnu.org/licenses/>.
  25  * ----------------------------------------------------------------------
  26  *
  27  */
  28
  29 #include "gnushogi.h"
  30
  31 #define O_BINARY 0
  32
  33 #if HAVE_UNISTD_H
  34 /* Declarations of read(), write(), close(), and lseek(). */
  35 #include <unistd.h>
  36 #endif
  37
  38 #if HAVE_FCNTL_H
  39 #include <fcntl.h>
  40 #endif
  41
  42 #include "book.h"
  43
  44 unsigned booksize = BOOKSIZE;
  45 unsigned short bookmaxply = BOOKMAXPLY;
  46 unsigned bookcount = 0;
  47
  48 #ifdef BOOK
  49 char *bookfile = BOOK;
  50 #else
  51 char *bookfile = NULL;
  52 #endif
  53
  54 #ifdef BINBOOK
  55 char *binbookfile = BINBOOK;
  56 #else
  57 char *binbookfile = NULL;
  58 #endif
  59
  60 static char bmvstr[3][7];
  61
  62 static ULONG bhashbd;
  63 static ULONG bhashkey;
  64
  65
  66 /*
  67  * Balgbr(f, t, flag)
  68  *
  69  * Generate move strings in different formats.
  70  */
  71
  72 void
  73 Balgbr(short f, short t, short flag)
  74 {
  75     short promoted = false;
  76
  77     if ((f & 0x80) != 0)
  78     {
  79         f &= 0x7f;
  80         promoted = true;
  81     }
  82
  83     if (f > NO_SQUARES)
  84     {
  85         short piece;
  86         piece = f - NO_SQUARES;
  87
  88         if (f > (NO_SQUARES + NO_PIECES))
  89             piece -= NO_PIECES;
  90
  91         flag = (dropmask | piece);
  92     }
  93
  94     if ((t & 0x80) != 0)
  95     {
  96         flag |= promote;
  97         t &= 0x7f;
  98     }
  99
 100     if ((f == t) && ((f != 0) || (t != 0)))
 101     {
 102         /*
 103          * error in algbr: FROM=TO=t
 104          */
 105
 106         bmvstr[0][0] = bmvstr[1][0] = bmvstr[2][0] = '\0';
 107     }
 108     else
 109     {
 110         if ((flag & dropmask) != 0)
 111         {
 112             /* bmvstr[0]: P*3c bmvstr[1]: P'3c */
 113             short piece = flag & pmask;
 114             bmvstr[0][0] = pxx[piece];
 115             bmvstr[0][1] = '*';
 116             bmvstr[0][2] = cxx[column(t)];
 117             bmvstr[0][3] = rxx[row(t)];
 118             bmvstr[0][4] = bmvstr[2][0] = '\0';
 119             strcpy(bmvstr[1], bmvstr[0]);
 120             bmvstr[1][1] = '\'';
 121         }
 122         else
 123         {
 124             if ((f != 0) || (t != 0))
 125             {
 126                 /* algebraic notation */
 127                 /* bmvstr[0]: 7g7f bmvstr[1]:
 128                  * (+)P7g7f(+) bmvstr[2]: (+)P7f(+) */
 129                 bmvstr[0][0] = cxx[column(f)];
 130                 bmvstr[0][1] = rxx[row(f)];
 131                 bmvstr[0][2] = cxx[column(t)];
 132                 bmvstr[0][3] = rxx[row(t)];
 133                 bmvstr[0][4] = '\0';
 134
 135                 if (promoted)
 136                 {
 137                     bmvstr[1][0] = bmvstr[2][0] = '+';
 138                     bmvstr[1][1] = bmvstr[2][1] = pxx[board[f]];
 139                     strcpy(&bmvstr[1][2], &bmvstr[0][0]);
 140                     strcpy(&bmvstr[2][2], &bmvstr[0][2]);
 141                 }
 142                 else
 143                 {
 144                     bmvstr[1][0] = bmvstr[2][0] = pxx[board[f]];
 145                     strcpy(&bmvstr[1][1], &bmvstr[0][0]);
 146                     strcpy(&bmvstr[2][1], &bmvstr[0][2]);
 147                 }
 148
 149                 if (flag & promote)
 150                 {
 151                     strcat(bmvstr[0], "+");
 152                     strcat(bmvstr[1], "+");
 153                     strcat(bmvstr[2], "+");
 154                 }
 155             }
 156             else
 157             {
 158                 bmvstr[0][0] = bmvstr[1][0] = bmvstr[2][0] = '\0';
 159             }
 160         }
 161     }
 162 }
 163
 164
 165
 166
 167 #ifndef QUIETBOOKGEN
 168 void
 169 bkdisplay(char *s, int cnt, int moveno)
 170 {
 171     static short pnt;
 172     struct leaf  *node;
 173     int r, c, l;
 174
 175     pnt = TrPnt[2];
 176     printf("matches = %d\n", cnt);
 177     printf("inout move is :%s: move number %d side %s\n",
 178             s, moveno / 2 + 1, (moveno & 1) ? "white" : "black");
 179
 180 #ifndef SEMIQUIETBOOKGEN
 181     printf("legal moves are \n");
 182
 183     while (pnt < TrPnt[3])
 184     {
 185         node = &Tree[pnt++];
 186
 187         if (is_promoted[board[node->f]] )
 188             Balgbr(node->f | 0x80, node->t, (short) node->flags);
 189         else
 190             Balgbr(node->f, node->t, (short) node->flags);
 191
 192         printf("%s %s %s\n",
 193                bmvstr[0], bmvstr[1], bmvstr[2]);
 194     }
 195
 196     printf("\n current board is\n");
 197
 198     for (r = (NO_ROWS - 1); r >= 0; r--)
 199     {
 200         for (c = 0; c <= (NO_COLS - 1); c++)
 201         {
 202             char pc;
 203
 204             l = locn(r, c);
 205             pc = (is_promoted[board[l]] ? '+' : ' ');
 206
 207             if (color[l] == neutral)
 208                 printf(" -");
 209             else if (color[l] == black)
 210                 printf("%c%c", pc, qxx[board[l]]);
 211             else
 212                 printf("%c%c", pc, pxx[board[l]]);
 213         }
 214
 215         printf("\n");
 216     }
 217
 218     printf("\n");
 219     {
 220         short color;
 221
 222         for (color = black; color <= white; color++)
 223         {
 224             short piece, c;
 225
 226             printf((color == black) ? "black " : "white ");
 227
 228             for (piece = pawn; piece <= king; piece++)
 229             {
 230                 if ((c = Captured[color][piece]))
 231                     printf("%i%c ", c, pxx[piece]);
 232             }
 233
 234             printf("\n");
 235         };
 236     }
 237 #endif /* SEMIQUIETBOOKGEN */
 238 }
 239
 240 #endif /* QUIETBOOKGEN */
 241
 242
 243
 244 /*
 245  * BVerifyMove(s, mv, moveno)
 246  *
 247  * Compare the string 's' to the list of legal moves available for the
 248  * opponent. If a match is found, make the move on the board.
 249  */
 250
 251 int
 252 BVerifyMove(char *s, unsigned short *mv, int moveno)
 253 {
 254     static short pnt, tempb, tempc, tempsf, tempst, cnt;
 255     static struct leaf xnode;
 256     struct leaf  *node;
 257
 258     *mv = 0;
 259     cnt = 0;
 260     MoveList(opponent, 2, -2, true);
 261     pnt = TrPnt[2];
 262
 263     while (pnt < TrPnt[3])
 264     {
 265         node = &Tree[pnt++];
 266
 267         if (is_promoted[board[node->f]] )
 268             Balgbr(node->f | 0x80, node->t, (short) node->flags);
 269         else
 270             Balgbr(node->f, node->t, (short) node->flags);
 271
 272         if (strcmp(s, bmvstr[0]) == 0 || strcmp(s, bmvstr[1]) == 0 ||
 273             strcmp(s, bmvstr[2]) == 0)
 274         {
 275             cnt++;
 276             xnode = *node;
 277         }
 278     }
 279
 280     if (cnt == 1)
 281     {
 282         short blockable;
 283
 284         MakeMove(opponent, &xnode, &tempb,
 285                  &tempc, &tempsf, &tempst, &INCscore);
 286
 287         if (SqAttacked(PieceList[opponent][0], computer, &blockable))
 288         {
 289             UnmakeMove(opponent, &xnode, &tempb, &tempc, &tempsf, &tempst);
 290             /* Illegal move in check */
 291 #if !defined QUIETBOOKGEN
 292             /* 077: "Illegal move (in check) %s" */
 293             printf(CP[77]);
 294             printf("\n");
 295             bkdisplay(s, cnt, moveno);
 296 #endif
 297             return false;
 298         }
 299         else
 300         {
 301             *mv = (xnode.f << 8) | xnode.t;
 302
 303             if (is_promoted[board[xnode.t]] )
 304                 Balgbr(xnode.f | 0x80, xnode.t, false);
 305             else
 306                 Balgbr(xnode.f, xnode.t, false);
 307
 308             return true;
 309         }
 310     }
 311
 312     /* Illegal move */
 313 #if !defined QUIETBOOKGEN
 314     /* 075: "Illegal move (no match)%s\n" */
 315     printf(CP[75], s);
 316     bkdisplay(s, cnt, moveno);
 317 #endif
 318     return false;
 319 }
 320
 321
 322
 323
 324 /*
 325  * RESET()
 326  *
 327  * Reset the board and other variables to start a new game.
 328  *
 329  */
 330
 331 void
 332 RESET(void)
 333 {
 334     short l;
 335
 336     flag.illegal = flag.mate = flag.post = flag.quit
 337         = flag.reverse = flag.bothsides = flag.onemove = flag.force
 338         = false;
 339
 340     flag.material = flag.coords = flag.hash = flag.easy
 341         = flag.beep = flag.rcptr
 342         = true;
 343
 344     flag.stars = flag.shade = flag.back = flag.musttimeout = false;
 345     flag.gamein = false;
 346     GenCnt   = 0;
 347     GameCnt  = 0;
 348     CptrFlag[0] = TesujiFlag[0] = false;
 349     opponent = black;
 350     computer = white;
 351
 352     for (l = 0; l < NO_SQUARES; l++)
 353     {
 354         board[l]   = Stboard[l];
 355         color[l]   = Stcolor[l];
 356         Mvboard[l] = 0;
 357     }
 358
 359     ClearCaptured();
 360     InitializeStats();
 361     hashbd = hashkey = 0;
 362 }
 363
 364
 365
 366 static
 367 int
 368 Vparse (FILE * fd, USHORT *mv, USHORT *flags, USHORT side, int moveno)
 369 {
 370     int c, i;
 371     char s[255];
 372
 373     *flags = 0;
 374
 375     while (true)
 376     {
 377         while (((c = getc(fd)) == ' ')
 378                || (c == '!') || (c == '/') || (c == '\n'));
 379
 380         if (c == '(')
 381         {
 382             /* amount of time spent for the last move */
 383             while (((c = getc(fd)) != ')') && (c != EOF));
 384
 385             if (c == ')')
 386             {
 387                 while (((c = getc(fd)) == ' ') || (c == '\n'));
 388             }
 389         }
 390
 391         if (c == '[')
 392         {
 393             /* comment for the actual game */
 394             while (((c = getc(fd))) != ']' && (c != EOF));
 395
 396             if (c == ']')
 397             {
 398                 while (((c = getc(fd))) == ' ' || (c == '\n'));
 399             }
 400         }
 401
 402         if (c == '\r')
 403             continue;
 404
 405         if (c == '#')
 406         {
 407             /* comment */
 408             do
 409             {
 410                 c = getc(fd);
 411
 412                 if (c == '\r')
 413                     continue;
 414                 /* goes to end of line */
 415
 416                 if (c == '\n')
 417                     return 0;
 418
 419                 if (c == EOF)
 420                     return -1;
 421             }
 422             while (true);
 423         }
 424
 425         s[i = 0] = (char) c;
 426
 427         while ((c >= '0') && (c <= '9'))
 428         {
 429             c = getc(fd);
 430             s[++i] = (char) c;
 431         }
 432
 433         if (c == '.')
 434         {
 435             while (((c = getc(fd)) == ' ') || (c == '.') || (c == '\n'));
 436             s[i = 0] = (char) c;
 437         }
 438
 439         while (((c = getc(fd)) != '?') && (c != '!') && (c != ' ')
 440                && (c != '(') && (c != '\n') && (c != '\t') && (c != EOF))
 441         {
 442             if (c == '\r')
 443                 continue;
 444
 445             if ((c != 'x') && (c != '-') && (c != ',')
 446                 && (c != ';') && (c != '='))
 447             {
 448                 s[++i] = (char) c;
 449             }
 450         }
 451
 452         s[++i] = '\0';
 453
 454         if (c == '(')
 455         {
 456             while (((c = getc(fd)) != ')') && (c != EOF));
 457
 458             if (c == ')')
 459                 c = getc(fd);
 460         }
 461
 462         if (c == EOF)
 463             return -1;
 464
 465         if (s[0] == '#')
 466         {
 467             while ((c != '\n') && (c != EOF))
 468                 c = getc(fd);
 469
 470             if (c == EOF)
 471                 return -1;
 472             else
 473                 return 0;
 474         }
 475
 476         if (strcmp(s, "draw") == 0)
 477             continue;
 478         else if (strcmp(s, "1-0") == 0)
 479             continue;
 480         else if (strcmp(s, "0-1") == 0)
 481             continue;
 482         else if (strcmp(s, "Resigns") == 0)
 483             continue;
 484         else if (strcmp(s, "Resigns.") == 0)
 485             continue;
 486         else if (strcmp(s, "Sennichite") == 0)
 487             continue;
 488         else if (strcmp(s, "Sennichite.") == 0)
 489             continue;
 490         else if (strcmp(s, "Jishogi") == 0)
 491             continue;
 492         else if (strcmp(s, "Jishogi.") == 0)
 493             continue;
 494
 495         bhashkey = hashkey;
 496         bhashbd  = hashbd;
 497
 498         i = BVerifyMove(s, mv, moveno);
 499
 500         if (c == '?')
 501         {
 502             /* Bad move, not for the program to play */
 503             *flags |= BADMOVE;  /* Flag it ! */
 504             while (((c = getc(fd)) == '?') || (c == '!') || (c == '/'));
 505         }
 506 #ifdef EASY_OPENINGS
 507         else if (c == '~')
 508         {
 509             /* Do not use by computer */
 510             *flags |= BADMOVE;  /* Flag it ! */
 511
 512             while (((c = getc(fd)) == '?') || (c == '!') || (c == '/'));
 513         }
 514 #endif
 515         else if (c == '!')
 516         {
 517             /* Good move */
 518             *flags |= GOODMOVE; /* Flag it ! */
 519
 520             while (((c = getc(fd)) == '?') || (c == '!') || (c == '/'));
 521         }
 522         else if (c == '\r')
 523         {
 524             c = getc(fd);
 525         }
 526
 527         if (c == '(' )
 528             while (((c = getc(fd)) != ')') && (c != EOF));
 529
 530         if (!i)
 531         {
 532             /* flush to start of next */
 533             while (((c = getc(fd)) != '#') && (c != EOF));
 534
 535             if (c == EOF)
 536             {
 537                 return -1;
 538             }
 539             else
 540             {
 541                 ungetc(c, fd);
 542                 return i;
 543             }
 544         }
 545
 546         return i;
 547     }
 548 }
 549
 550
 551 static struct gdxadmin ADMIN;
 552 struct gdxadmin B;
 553 static struct gdxdata DATA;
 554
 555 /* lts(l) returns most significant 16 bits of l */
 556
 557 #if SIZEOF_LONG == 8  /* 64-bit long i.e. 8 bytes */
 558 #  define lts(x) (USHORT)(((x >> 48) & 0xfffe) | side)
 559 #else
 560 #  if defined USE_LTSIMP
 561 static USHORT ltsimp(long x)
 562 {
 563     USHORT n;
 564     n = (((x >> 16) & 0xfffe));
 565     return n;
 566 }
 567 #    define lts(x) (USHORT)(ltsimp(x) | side)
 568 #  else
 569 #    define lts(x) (USHORT)(((x >> 16)&0xfffe) | side)
 570 #  endif
 571 #endif
 572
 573
 574 /* #define HashValue(l) lts(l) */
 575 #define HashValue(l) (USHORT)(l & 0xffff)
 576
 577
 578 static int gfd;
 579 static ULONG currentoffset;
 580
 581
 582 #define MAXOFFSET(B) ((B.booksize - 1) * sizeof_gdxdata + sizeof_gdxadmin)
 583
 584 #define HashOffset(hashkey, B) \
 585 { \
 586   currentoffset = ((ULONG)hashkey % B.booksize) \
 587     * sizeof_gdxdata + sizeof_gdxadmin; \
 588 }
 589
 590
 591 #define NextOffset(B) \
 592 { \
 593   currentoffset += sizeof_gdxdata; \
 594   if (currentoffset > B.maxoffset) \
 595     currentoffset = sizeof_gdxadmin; \
 596 }
 597
 598
 599 #define WriteAdmin() \
 600 { \
 601   lseek(gfd, 0, 0); \
 602   write(gfd, (char *)&ADMIN, sizeof_gdxadmin); \
 603 }
 604
 605 #define WriteData() \
 606 { \
 607   if (mustwrite ) \
 608   { \
 609     lseek(gfd, currentoffset, 0); \
 610     write(gfd, (char *)&DATA, sizeof_gdxdata); \
 611     mustwrite = false; \
 612   } \
 613 }
 614
 615 static int ReadAdmin(void)
 616 {
 617     lseek(gfd, 0, 0);
 618     return (sizeof_gdxadmin == read(gfd, (char *)&ADMIN, sizeof_gdxadmin));
 619 }
 620
 621 static int ReadData(struct gdxdata *DATA)
 622 {
 623     lseek(gfd, currentoffset, 0);
 624     return (sizeof_gdxdata == read(gfd, (char *)DATA, sizeof_gdxdata));
 625 }
 626
 627
 628 /*
 629  * GetOpenings()
 630  *
 631  * CHECKME: is this still valid esp. wrt gnushogi.book?
 632  *
 633  * Read in the Opening Book file and parse the algebraic notation for a move
 634  * into an unsigned integer format indicating the from and to square. Create
 635  * a linked list of opening lines of play, with entry->next pointing to the
 636  * next line and entry->move pointing to a chunk of memory containing the
 637  * moves. More Opening lines of up to 100 half moves may be added to
 638  * gnushogi.book. But now it's a hashed table by position which yields a move
 639  * or moves for each position. It no longer knows about openings per se only
 640  * positions and recommended moves in those positions.
 641  *
 642  */
 643
 644 void
 645 GetOpenings(void)
 646 {
 647     short i;
 648     int mustwrite = false, first;
 649     unsigned short xside, side;
 650     short c;
 651     USHORT mv, flags;
 652     unsigned int x;
 653     unsigned int games = 0;
 654     LONG collisions = 0;
 655     char msg[80];
 656
 657     FILE *fd;
 658
 659     if ((fd = fopen(bookfile, "r")) == NULL)
 660         fd = fopen("gnushogi.tbk", "r");
 661
 662     if (fd != NULL)
 663     {
 664         /* yes add to book */
 665         /* open book as writer */
 666         gfd = open(binbookfile, O_RDONLY | O_BINARY);
 667
 668         if (gfd >= 0)
 669         {
 670             if (ReadAdmin())
 671             {
 672                 B.bookcount = ADMIN.bookcount;
 673                 B.booksize = ADMIN.booksize;
 674                 B.maxoffset = ADMIN.maxoffset;
 675
 676                 if (B.booksize && !(B.maxoffset == MAXOFFSET(B)))
 677                 {
 678                     printf("bad format %s\n", binbookfile);
 679                     exit(1);
 680                 }
 681             }
 682             else
 683             {
 684                 printf("bad format %s\n", binbookfile);
 685                 exit(1);
 686             }
 687             close(gfd);
 688             gfd = open(binbookfile, O_RDWR | O_BINARY);
 689
 690         }
 691         else
 692         {
 693             gfd = open(binbookfile, O_RDWR | O_CREAT | O_BINARY, 0644);
 694
 695             ADMIN.bookcount = B.bookcount = 0;
 696             ADMIN.booksize = B.booksize = booksize;
 697             B.maxoffset = ADMIN.maxoffset = MAXOFFSET(B);
 698             DATA.hashbd = 0;
 699             DATA.hashkey = 0;
 700             DATA.bmove = 0;
 701             DATA.flags = 0;
 702             DATA.hint = 0;
 703             DATA.count = 0;
 704             write(gfd, (char *)&ADMIN, sizeof_gdxadmin);
 705             printf("creating bookfile %s %ld %ld\n",
 706                     binbookfile, B.maxoffset, B.booksize);
 707
 708             for (x = 0; x < B.booksize; x++)
 709             {
 710                 write(gfd, (char *)&DATA, sizeof_gdxdata);
 711             }
 712         }
 713
 714         if (gfd >= 0)
 715         {
 716             /* setvbuf(fd, buffr, _IOFBF, 2048); */
 717             side = black;
 718             xside = white;
 719             hashbd = hashkey = 0;
 720             i = 0;
 721
 722             while ((c = Vparse(fd, &mv, &flags, side, i)) >= 0)
 723             {
 724                 if (c == 1)
 725                 {
 726                     /*
 727                      * If this is not the first move of an opening and
 728                      * if it's the first time we have seen it then
 729                      * save the next move as a hint.
 730                      */
 731                     i++;
 732
 733                     if (i < bookmaxply + 2)
 734                     {
 735                         if (i > 1 && !(flags & BADMOVE))
 736                             DATA.hint = mv;
 737
 738                         if (i < bookmaxply + 1)
 739                         {
 740                             /*
 741                              * See if this position and move already
 742                              * exist from some other opening.
 743                              */
 744
 745                             WriteData();
 746                             HashOffset(bhashkey, B);
 747                             first = true;
 748
 749                             while (true)
 750                             {
 751                                 if (!ReadData(&DATA))
 752                                     break; /* corrupted binbook file */
 753
 754                                 if (DATA.bmove == 0)
 755                                     break;  /* free entry */
 756
 757                                 if (DATA.hashkey == HashValue(bhashkey)
 758                                     && DATA.hashbd == bhashbd)
 759                                 {
 760                                     if (DATA.bmove == mv)
 761                                     {
 762                                         /*
 763                                          * Yes, so just bump count - count
 764                                          * is used to choose the opening
 765                                          * move in proportion to its
 766                                          * presence in the book.
 767                                          */
 768
 769                                         DATA.count++;
 770                                         DATA.flags |= flags;
 771                                         mustwrite = true;
 772                                         break;
 773                                     }
 774                                     else
 775                                     {
 776                                         if (first)
 777                                             collisions++;
 778
 779                                         if (DATA.flags & LASTMOVE)
 780                                         {
 781                                             DATA.flags &= (~LASTMOVE);
 782                                             mustwrite = true;
 783                                             WriteData();
 784                                         }
 785                                     }
 786                                 }
 787
 788                                 NextOffset(B);
 789                                 first = false;
 790                             }
 791
 792                             /*
 793                              * Doesn't exist so add it to the book.
 794                              */
 795
 796                             if (!mustwrite)
 797                             {
 798                                 B.bookcount++;
 799
 800                                 if ((B.bookcount % 1000) == 0)
 801                                 {
 802                                     /* CHECKME: may want to get rid of this,
 803                                      * especially for xshogi. */
 804                                     printf("%ld rec %d openings "
 805                                            "processed\n",
 806                                            B.bookcount, games);
 807                                 }
 808
 809                                 /* initialize a record */
 810                                 DATA.hashbd = bhashbd;
 811                                 DATA.hashkey = HashValue(bhashkey);
 812                                 DATA.bmove = mv;
 813                                 DATA.flags = flags | LASTMOVE;
 814                                 DATA.count = 1;
 815                                 DATA.hint = 0;
 816                                 mustwrite = true;
 817                             }
 818                         }
 819                     }
 820
 821                     computer = opponent;
 822                     opponent = computer ^ 1;
 823
 824                     xside = side;
 825                     side = side ^ 1;
 826                 }
 827                 else if (i > 0)
 828                 {
 829                     /* reset for next opening */
 830                     games++;
 831                     WriteData();
 832                     RESET();
 833                     i = 0;
 834                     side = black;
 835                     xside = white;
 836
 837                 }
 838             }
 839
 840             WriteData();
 841             fclose(fd);
 842             /* write admin rec with counts */
 843             ADMIN.bookcount = B.bookcount;
 844             WriteAdmin();
 845
 846             close(gfd);
 847         }
 848     }
 849
 850     if (binbookfile != NULL)
 851     {
 852         /* open book as reader */
 853         gfd = open(binbookfile, O_RDONLY | O_BINARY);
 854
 855         if (gfd >= 0)
 856         {
 857             if (ReadAdmin() && (!ADMIN.booksize
 858                                 || (ADMIN.maxoffset == MAXOFFSET(ADMIN))))
 859             {
 860                 B.bookcount = ADMIN.bookcount;
 861                 B.booksize  = ADMIN.booksize;
 862                 B.maxoffset = ADMIN.maxoffset;
 863             }
 864             else
 865             {
 866                 printf("bad format %s\n", binbookfile);
 867                 exit(1);
 868             }
 869
 870         }
 871         else
 872         {
 873             B.bookcount = 0;
 874             B.booksize = booksize;
 875
 876         }
 877
 878         /* 213: "Book used %d(%d)." */
 879         sprintf(msg, CP[213], B.bookcount, B.booksize);
 880         ShowMessage(msg);
 881     }
 882
 883     /* Set everything back to start the game. */
 884     Book = BOOKFAIL;
 885     RESET();
 886
 887     /* Now get ready to play .*/
 888     if (!B.bookcount)
 889     {
 890         /* 212: "Can't find book." */
 891         ShowMessage(CP[212]);
 892         Book = 0;
 893     }
 894 }
 895
 896
 897
 898 /*
 899  * OpeningBook(hint, side)
 900  *
 901  * Go through each of the opening lines of play and check for a match with
 902  * the current game listing. If a match occurs, generate a random
 903  * number. If this number is the largest generated so far then the next
 904  * move in this line becomes the current "candidate".  After all lines are
 905  * checked, the candidate move is put at the top of the Tree[] array and
 906  * will be played by the program.  Note that the program does not handle
 907  * book transpositions.
 908  */
 909
 910 int
 911 OpeningBook(unsigned short *hint, short side)
 912 {
 913     unsigned short r, m;
 914     int possibles = TrPnt[2] - TrPnt[1];
 915
 916     gsrand((unsigned int) time((long *) 0));
 917     m = 0;
 918
 919     /*
 920      * Find all the moves for this position  - count them and get their
 921      * total count.
 922      */
 923
 924     {
 925         USHORT i, x;
 926         USHORT rec = 0;
 927         USHORT summ = 0;
 928         USHORT h = 0, b = 0;
 929         struct gdxdata OBB[128];
 930
 931         if (B.bookcount == 0)
 932         {
 933             Book--;
 934             return false;
 935         }
 936
 937         x = 0;
 938         HashOffset(hashkey, B);
 939 #ifdef BOOKTEST
 940         printf("looking for book move, bhashbd = 0x%lx bhashkey = 0x%x\n",
 941                (ULONG)hashbd, HashValue(hashkey));
 942 #endif
 943         while (true)
 944         {
 945             if (!ReadData(&OBB[x]))
 946                 break;
 947
 948             if (OBB[x].bmove == 0)
 949                 break;
 950
 951 #ifdef BOOKTEST
 952             printf("compare with bhashbd = 0x%lx bhashkey = 0x%x\n",
 953                    OBB[x].hashbd, OBB[x].hashkey);
 954 #endif
 955             if ((OBB[x].hashkey == HashValue(hashkey))
 956                 && (OBB[x].hashbd == (ULONG)hashbd))
 957             {
 958                 x++;
 959
 960                 if (OBB[x-1].flags & LASTMOVE)
 961                     break;
 962             }
 963
 964             NextOffset(B);
 965         }
 966
 967 #ifdef BOOKTEST
 968         printf("%d book move(s) found.\n", x);
 969 #endif
 970
 971         if (x == 0)
 972         {
 973             Book--;
 974             return false;
 975         }
 976
 977         for (i = 0; i < x; i++)
 978         {
 979             if (OBB[i].flags & BADMOVE)
 980             {
 981                 m = OBB[i].bmove;
 982
 983                 /* Is the move in the MoveList? */
 984                 for (b = TrPnt[1]; b < (unsigned) TrPnt[2]; b++)
 985                 {
 986                     if (((Tree[b].f << 8) | Tree[b].t) == m)
 987                     {
 988                         if (--possibles)
 989                             Tree[b].score = DONTUSE;
 990                         break;
 991                     }
 992                 }
 993             }
 994             else
 995             {
 996 #if defined BOOKTEST
 997                 char s[20];
 998                 movealgbr(m = OBB[i].bmove, s);
 999                 printf("finding book move: %s\n", s);
1000 #endif
1001                 summ += OBB[i].count;
1002             }
1003         }
1004
1005         if (summ == 0)
1006         {
1007             Book--;
1008             return false;
1009         }
1010
1011         r = (urand() % summ);
1012
1013         for (i = 0; i < x; i++)
1014         {
1015             if (!(OBB[i].flags & BADMOVE))
1016             {
1017                 if (r < OBB[i].count)
1018                 {
1019                     rec = i;
1020                     break;
1021                 }
1022                 else
1023                 {
1024                     r -= OBB[i].count;
1025                 }
1026             }
1027         }
1028
1029         h = OBB[rec].hint;
1030         m = OBB[rec].bmove;
1031
1032         /* Make sure the move is in the MoveList. */
1033         for (b = TrPnt[1]; b < (unsigned) TrPnt[2]; b++)
1034         {
1035             if (((Tree[b].f << 8) | Tree[b].t) == m)
1036             {
1037                 Tree[b].flags |= book;
1038                 Tree[b].score = 0;
1039                 break;
1040             }
1041         }
1042
1043         /* Make sure it's the best. */
1044
1045         pick(TrPnt[1], TrPnt[2] - 1);
1046
1047         if (Tree[TrPnt[1]].score)
1048         {
1049             /* no! */
1050             Book--;
1051             return false;
1052         }
1053
1054         /* Ok, pick up the hint and go. */
1055         *hint = h;
1056         return true;
1057     }
1058
1059     Book--;
1060     return false;
1061 }
1062
1063
1064