git.sesse.net Git - pgn-extract/blob - grammar.c

   1 /*
   2  *  Program: pgn-extract: a Portable Game Notation (PGN) extractor.
   3  *  Copyright (C) 1994-2014 David Barnes
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 1, or (at your option)
   7  *  any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License
  15  *  along with this program; if not, write to the Free Software
  16  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  *
  18  *  David Barnes may be contacted as D.J.Barnes@kent.ac.uk
  19  *  http://www.cs.kent.ac.uk/people/staff/djb/
  20  *
  21  */
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <ctype.h>
  26 #include "bool.h"
  27 #include "mymalloc.h"
  28 #include "defs.h"
  29 #include "typedef.h"
  30 #include "tokens.h"
  31 #include "taglist.h"
  32 #include "lex.h"
  33 #include "moves.h"
  34 #include "map.h"
  35 #include "lists.h"
  36 #include "apply.h"
  37 #include "output.h"
  38 #include "eco.h"
  39 #include "end.h"
  40 #include "grammar.h"
  41 #include "hashing.h"
  42
  43 static TokenType current_symbol = NO_TOKEN;
  44
  45 /* Keep track of which RAV level we are at.
  46  * This is used to check whether a TERMINATING_RESULT is the final one
  47  * and whether NULL_MOVEs are allowed.
  48  */
  49 static unsigned RAV_level = 0;
  50
  51 /* At what file position the current game started. */
  52 static long game_start_position = -1;
  53
  54 /* Retain details of the header of a game.
  55  * This comprises the Tags and any comment prefixing the
  56  * moves of the game.
  57  */
  58 static struct{
  59     /* The tag values. */
  60     char **Tags;
  61     unsigned header_tags_length;
  62     CommentList *prefix_comment;
  63 } GameHeader;
  64
  65 static void ParseOptGameList(SourceFileType file_type);
  66 static Boolean ParseGame(Move **returned_move_list);
  67 Boolean ParseOptTagList(void);
  68 Boolean ParseTag(void);
  69 static Move *ParseMoveList(void);
  70 static Move *ParseMoveAndVariants(void);
  71 static Move *ParseMove(void);
  72 static Move *ParseMoveUnit(void);
  73 static CommentList *ParseOptCommentList(void);
  74 Boolean ParseOptMoveNumber(void);
  75 static StringList *ParseOptNAGList(void);
  76 static Variation *ParseOptVariantList(void);
  77 static Variation *ParseVariant(void);
  78 static char *ParseResult(void);
  79
  80 static void setup_for_new_game(void);
  81 void free_tags(void);
  82 static void check_result(char **Tags,const char *terminating_result);
  83 static void free_comment_list(CommentList *comment_list);
  84 static void DealWithEcoLine(Move *move_list);
  85 static void DealWithGame(Move *move_list);
  86 static Boolean finished_processing(SourceFileType file_type);
  87
  88     /* Initialise the game header structure to contain
  89      * space for the default number of tags.
  90      * The space will have to be increased if new tags are
  91      * identified in the program source.
  92      */
  93 void
  94 init_game_header(void)
  95 {
  96     unsigned i;
  97     GameHeader.header_tags_length = ORIGINAL_NUMBER_OF_TAGS;
  98     GameHeader.Tags = (char **) MallocOrDie(GameHeader.header_tags_length*
  99                     sizeof(*GameHeader.Tags));
 100     for(i = 0; i < GameHeader.header_tags_length; i++){
 101         GameHeader.Tags[i] = (char *) NULL;
 102     }
 103 }
 104
 105 void
 106 increase_game_header_tags_length(unsigned new_length)
 107 {   unsigned i;
 108
 109     if(new_length <= GameHeader.header_tags_length){
 110         fprintf(GlobalState.logfile,
 111                 "Internal error: inappropriate length %d ",new_length);
 112         fprintf(GlobalState.logfile,
 113                 " passed to increase_game_header_tags().\n");
 114         exit(1);
 115     }
 116     GameHeader.Tags = (char **) ReallocOrDie((void *) GameHeader.Tags,
 117                                       new_length*sizeof(*GameHeader.Tags));
 118     for(i = GameHeader.header_tags_length; i < new_length; i++){
 119         GameHeader.Tags[i] = NULL;
 120     }
 121     GameHeader.header_tags_length = new_length;
 122 }
 123
 124         /* Try to open the given file. Error and exit on failure. */
 125 FILE *
 126 must_open_file(const char *filename,const char *mode)
 127 {   FILE *fp;
 128
 129     fp = fopen(filename,mode);
 130     if(fp == NULL){
 131         fprintf(GlobalState.logfile,"Unable to open the file: \"%s\"\n",
 132                 filename);
 133         exit(1);
 134     }
 135     return fp;
 136 }
 137
 138         /* Print out on outfp the current details and
 139          * terminate with a newline.
 140          */
 141 void
 142 report_details(FILE *outfp)
 143 {
 144       if(GameHeader.Tags[WHITE_TAG] != NULL){
 145           fprintf(outfp,"%s - ",GameHeader.Tags[WHITE_TAG]);
 146       }
 147       if(GameHeader.Tags[BLACK_TAG] != NULL){
 148           fprintf(outfp,"%s ",GameHeader.Tags[BLACK_TAG]);
 149       }
 150
 151       if(GameHeader.Tags[EVENT_TAG] != NULL){
 152           fprintf(outfp,"%s ",GameHeader.Tags[EVENT_TAG]);
 153       }
 154       if(GameHeader.Tags[SITE_TAG] != NULL){
 155           fprintf(outfp,"%s ",GameHeader.Tags[SITE_TAG]);
 156       }
 157
 158       if(GameHeader.Tags[DATE_TAG] != NULL){
 159           fprintf(outfp,"%s ",GameHeader.Tags[DATE_TAG]);
 160       }
 161       putc('\n',outfp);
 162       fflush(outfp);
 163 }
 164
 165         /* Check that terminating_result is consistent with
 166          * Tags[RESULT_TAG].  If the latter is missing, fill it
 167          * in from terminating_result.
 168          */
 169 static void
 170 check_result(char **Tags,const char *terminating_result)
 171 {   char *result_tag = Tags[RESULT_TAG];
 172
 173     if(terminating_result != NULL){
 174         if((result_tag == NULL) || (*result_tag == '\0') ||
 175                     (strcmp(result_tag,"?") == 0)){
 176             /* Use a copy of terminating result. */
 177             result_tag = copy_string(terminating_result);
 178             Tags[RESULT_TAG] = result_tag;
 179         }
 180         else if((result_tag != NULL) &&
 181                     (strcmp(terminating_result,"*") != 0) &&
 182                     (strcmp(result_tag,terminating_result) != 0)){
 183             print_error_context(GlobalState.logfile);
 184             fprintf(GlobalState.logfile,
 185                         "Inconsistent result strings in the following game.\n");
 186             report_details(GlobalState.logfile);
 187         }
 188         else{
 189             /* Ok. */
 190         }
 191     }
 192 }
 193
 194         /* Select which file to write to based upon the game state.
 195          * This will depend upon:
 196          *        Whether the number of games per file is limited.
 197          *        Whether ECO_level > DONT_DIVIDE.
 198          */
 199
 200 static FILE *
 201 select_output_file(StateInfo *GameState,const char *eco)
 202 {
 203     if(GameState->games_per_file > 0){
 204         if((GameState->num_games_matched % GameState->games_per_file) == 0){
 205               /* Time to open the next one. */
 206               char filename[50];
 207
 208               if(GameState->outputfile != NULL){
 209                   (void) fclose(GameState->outputfile);
 210               }
 211               sprintf(filename,"%u%s",
 212                         GameState->next_file_number,
 213                         output_file_suffix(GameState->output_format));
 214               GameState->outputfile = must_open_file(filename,"w");
 215               GameState->next_file_number++;
 216         }
 217     }
 218     else if(GameState->ECO_level > DONT_DIVIDE){
 219         /* Open a file of the appropriate name. */
 220         if(GameState->outputfile != NULL){
 221             /* @@@ In practice, this might need refinement.
 222              * Repeated opening and closing may prove inefficient.
 223              */
 224             (void) fclose(GameState->outputfile);
 225             GameState->outputfile = open_eco_output_file(
 226                                 GameState->ECO_level,
 227                                 eco);
 228         }
 229     }
 230     else{
 231     }
 232     return GameState->outputfile;
 233 }
 234
 235   /*
 236    * Conditions for finishing processing, other than all the input
 237    * having been processed.
 238    */
 239 static Boolean finished_processing(SourceFileType file_type)
 240 {
 241     return ((file_type != ECOFILE && at_end_of_input()) ||
 242             (GlobalState.matching_game_number > 0 &&
 243              GlobalState.num_games_matched == GlobalState.matching_game_number));
 244 }
 245
 246 static void
 247 ParseOptGameList(SourceFileType file_type)
 248 {   Move *move_list = NULL;
 249
 250     while(ParseGame(&move_list) && !finished_processing(file_type)){
 251         if(file_type == NORMALFILE){
 252             DealWithGame(move_list);
 253         }
 254         else if(file_type == CHECKFILE){
 255             DealWithGame(move_list);
 256         }
 257         else if(file_type == ECOFILE){
 258             if(move_list != NULL){
 259                 DealWithEcoLine(move_list);
 260             }
 261             else {
 262                 fprintf(GlobalState.logfile,"ECO line with zero moves.\n");
 263                 report_details(GlobalState.logfile);
 264             }
 265         }
 266         else{
 267             /* Unknown type. */
 268             free_tags();
 269             free_move_list(move_list);
 270         }
 271         move_list = NULL;
 272         setup_for_new_game();
 273     }
 274     if(file_type == ECOFILE && GlobalState.dump_eco) {
 275         dumpEcoTable();
 276         exit(0);
 277     }
 278 }
 279
 280         /* Parse a game and return a pointer to any valid list of moves
 281          * in returned_move_list.
 282          */
 283 static Boolean
 284 ParseGame(Move **returned_move_list)
 285 {   /* Boolean something_found = FALSE; */
 286     CommentList *prefix_comment;
 287     Move *move_list = NULL;
 288     char *result;
 289     /* There shouldn't be a hanging comment before the result,
 290      * but there sometimes is.
 291      */
 292     CommentList *hanging_comment;
 293
 294     /* Assume that we won't return anything. */
 295     *returned_move_list = NULL;
 296     /* Skip over any junk between games. */
 297     current_symbol = skip_to_next_game(current_symbol);
 298     prefix_comment = ParseOptCommentList();
 299     if(prefix_comment != NULL){
 300         /* Free this here, as it is hard to
 301          * know whether it belongs to the game or the file.
 302          * It is better to put game comments after the tags.
 303          */
 304         /* something_found = TRUE; */
 305         free_comment_list(prefix_comment);
 306         prefix_comment = NULL;
 307     }
 308     if(ParseOptTagList()){
 309         /* something_found = TRUE; */
 310     }
 311     /* @@@ Beware of comments and/or tags without moves. */
 312     move_list = ParseMoveList();
 313
 314     /* @@@ Look for a comment with no move text before the result. */
 315     hanging_comment = ParseOptCommentList();
 316     /* Append this to the final move, if there is one. */
 317
 318     /* Look for a result, even if there were no moves. */
 319     result = ParseResult();
 320     if(move_list != NULL){
 321         /* Find the last move. */
 322         Move *last_move = move_list;
 323
 324         while(last_move->next != NULL){
 325             last_move = last_move->next;
 326         }
 327         if(hanging_comment != NULL) {
 328             append_comments_to_move(last_move,hanging_comment);
 329         }
 330         if(result != NULL){
 331             /* Append it to the last move. */
 332             last_move->terminating_result = result;
 333             check_result(GameHeader.Tags,result);
 334             *returned_move_list = move_list;
 335         }
 336         else{
 337             fprintf(GlobalState.logfile,"Missing result.\n");
 338             report_details(GlobalState.logfile);
 339         }
 340         /* something_found = TRUE; */
 341     }
 342     else{
 343         /* @@@ Nothing to attach the comment to. */
 344         (void) free((void *) hanging_comment);
 345         hanging_comment = NULL;
 346         /*
 347          * Workaround for games with zero moves.
 348          * Check the result for consistency with the tags, but then
 349          * there is no move to attach it to.
 350          * When outputting a game, the missing result in this case
 351          * will have to be supplied from the tags.
 352          */
 353         check_result(GameHeader.Tags,result);
 354         if(result != NULL){
 355             (void) free((void *)result);
 356         }
 357         *returned_move_list = NULL;
 358     }
 359     return current_symbol != EOF_TOKEN;
 360 }
 361
 362 Boolean
 363 ParseOptTagList(void)
 364 {   Boolean something_found = FALSE;
 365     CommentList *prefix_comment;
 366
 367     while(ParseTag()){
 368         something_found = TRUE;
 369     }
 370     if(something_found){
 371         /* Perform any consistency checks. */
 372         if((GameHeader.Tags[SETUP_TAG] != NULL) &&
 373                 (strcmp(GameHeader.Tags[SETUP_TAG],"1") == 0)){
 374             /* There must be a FEN_TAG to go with it. */
 375             if(GameHeader.Tags[FEN_TAG] == NULL){
 376                  fprintf(GlobalState.logfile,
 377                         "Missing %s Tag to accompany %s Tag.\n",
 378                         tag_header_string(FEN_TAG),
 379                         tag_header_string(SETUP_TAG));
 380                 print_error_context(GlobalState.logfile);
 381             }
 382         }
 383     }
 384     prefix_comment = ParseOptCommentList();
 385     if(prefix_comment != NULL){
 386         GameHeader.prefix_comment = prefix_comment;
 387         something_found = TRUE;
 388     }
 389     return something_found;
 390 }
 391
 392 Boolean
 393 ParseTag(void)
 394 {   Boolean TagFound = TRUE;
 395
 396     if(current_symbol == TAG){
 397         TagName tag_index = yylval.tag_index;
 398
 399         current_symbol = next_token();
 400         if(current_symbol == STRING){
 401             char *tag_string = yylval.token_string;
 402
 403             if(tag_index < GameHeader.header_tags_length){
 404                 GameHeader.Tags[tag_index] = tag_string;
 405             }
 406             else{
 407                 print_error_context(GlobalState.logfile);
 408                 fprintf(GlobalState.logfile,
 409                         "Internal error: Illegal tag index %d for %s\n",
 410                         tag_index,tag_string);
 411                 exit(1);
 412             }
 413             current_symbol = next_token();
 414         }
 415         else{
 416             print_error_context(GlobalState.logfile);
 417             fprintf(GlobalState.logfile,"Missing tag string.\n");
 418         }
 419     }
 420     else if(current_symbol == STRING){
 421         print_error_context(GlobalState.logfile);
 422         fprintf(GlobalState.logfile,"Missing tag for %s.\n",yylval.token_string);
 423         (void) free((void *)yylval.token_string);
 424         current_symbol = next_token();
 425     }
 426     else{
 427         TagFound = FALSE;
 428     }
 429     return TagFound;
 430 }
 431
 432
 433 static Move *
 434 ParseMoveList(void)
 435 {   Move *head = NULL, *tail = NULL;
 436
 437     head = ParseMoveAndVariants();
 438     if(head != NULL){
 439         Move *next_move;
 440
 441         tail = head;
 442         while((next_move = ParseMoveAndVariants()) != NULL){
 443             tail->next = next_move;
 444             tail = next_move;
 445         }
 446     }
 447     return head;
 448 }
 449
 450 static Move *
 451 ParseMoveAndVariants(void)
 452 {   Move *move_details;
 453
 454     move_details = ParseMove();
 455     if(move_details != NULL){
 456         CommentList *comment;
 457
 458         move_details->Variants = ParseOptVariantList();
 459         comment = ParseOptCommentList();
 460         if(comment != NULL){
 461             append_comments_to_move(move_details,comment);
 462         }
 463     }
 464     return move_details;
 465 }
 466
 467
 468 static Move *
 469 ParseMove(void)
 470 {   Move *move_details = NULL;
 471
 472     if(ParseOptMoveNumber()){
 473     }
 474     /* @@@ Watch out for finding just the number. */
 475     move_details = ParseMoveUnit();
 476     if(move_details != NULL){
 477         CommentList *comment;
 478
 479         move_details->Nags = ParseOptNAGList();
 480         comment = ParseOptCommentList();
 481         if(comment != NULL){
 482             append_comments_to_move(move_details,comment);
 483         }
 484     }
 485     return move_details;
 486 }
 487
 488 static Move *
 489 ParseMoveUnit(void)
 490 {   Move *move_details = NULL;
 491
 492     if(current_symbol == MOVE){
 493         move_details = yylval.move_details;
 494
 495         if(move_details->class == NULL_MOVE && RAV_level == 0) {
 496             print_error_context(GlobalState.logfile);
 497             fprintf(GlobalState.logfile, "Null moves (--) only allowed in variations.\n");
 498         }
 499
 500         current_symbol = next_token();
 501         if(current_symbol == CHECK_SYMBOL){
 502             strcat((char *) move_details->move,"+");
 503             current_symbol = next_token();
 504             /* Sometimes + is followed by #, so cover this case. */
 505             if(current_symbol == CHECK_SYMBOL){
 506                 current_symbol = next_token();
 507             }
 508         }
 509         move_details->Comment = ParseOptCommentList();
 510     }
 511     return move_details;
 512 }
 513
 514 static CommentList *
 515 ParseOptCommentList(void)
 516 {   CommentList *head = NULL, *tail = NULL;
 517
 518     while(current_symbol == COMMENT){
 519         if(head == NULL){
 520             head = tail = yylval.comment;
 521         }
 522         else{
 523             tail->next = yylval.comment;
 524             tail = tail->next;
 525         }
 526         current_symbol = next_token();
 527     }
 528     return head;
 529 }
 530
 531 Boolean
 532 ParseOptMoveNumber(void)
 533 {   Boolean something_found = FALSE;
 534
 535     if(current_symbol == MOVE_NUMBER){
 536         current_symbol = next_token();
 537         something_found = TRUE;
 538     }
 539     return something_found;
 540 }
 541
 542 static StringList *
 543 ParseOptNAGList(void)
 544 {   StringList *nags = NULL;
 545
 546     while(current_symbol == NAG){
 547         if(GlobalState.keep_NAGs){
 548             nags = save_string_list_item(nags,yylval.token_string);
 549         }
 550         else{
 551             (void) free((void *)yylval.token_string);
 552         }
 553         current_symbol = next_token();
 554     }
 555     return nags;
 556 }
 557
 558 static Variation *
 559 ParseOptVariantList(void)
 560 {   Variation *head = NULL, *tail = NULL,
 561         *variation;
 562
 563     while((variation = ParseVariant()) != NULL){
 564         if(head == NULL){
 565             head = tail = variation;
 566         }
 567         else{
 568             tail->next = variation;
 569             tail = variation;
 570         }
 571     }
 572     return head;
 573 }
 574
 575 static Variation *
 576 ParseVariant(void)
 577 {   Variation *variation = NULL;
 578
 579     if(current_symbol == RAV_START){
 580         CommentList *prefix_comment;
 581         CommentList *suffix_comment;
 582         char *result = NULL;
 583         Move *moves;
 584
 585         RAV_level++;
 586         variation = MallocOrDie(sizeof(Variation));
 587
 588         current_symbol = next_token();
 589         prefix_comment = ParseOptCommentList();
 590         if(prefix_comment != NULL){
 591         }
 592         moves = ParseMoveList();
 593         if(moves == NULL){
 594             print_error_context(GlobalState.logfile);
 595             fprintf(GlobalState.logfile,"Missing move list in variation.\n");
 596         }
 597         result = ParseResult();
 598         if((result != NULL) && (moves != NULL)){
 599             /* Find the last move, to which to append the terminating
 600              * result.
 601              */
 602             Move *last_move = moves;
 603             CommentList *trailing_comment;
 604
 605             while(last_move->next != NULL){
 606                 last_move = last_move->next;
 607             }
 608             last_move->terminating_result = result;
 609             /* Accept a comment after the result, but it will
 610              * be printed out preceding the result.
 611              */
 612             trailing_comment = ParseOptCommentList();
 613             if(trailing_comment != NULL){
 614                 append_comments_to_move(last_move,trailing_comment);
 615             }
 616         }
 617         else{
 618             /* Ok. */
 619         }
 620         if(current_symbol == RAV_END){
 621             RAV_level--;
 622             current_symbol = next_token();
 623         }
 624         else{
 625             fprintf(GlobalState.logfile,"Missing ')' to close variation.\n");
 626         }
 627         suffix_comment = ParseOptCommentList();
 628         if(suffix_comment != NULL){
 629         }
 630         variation->prefix_comment = prefix_comment;
 631         variation->suffix_comment = suffix_comment;
 632         variation->moves = moves;
 633         variation->next = NULL;
 634     }
 635     return variation;
 636 }
 637
 638 static char *
 639 ParseResult(void)
 640 {   char *result = NULL;
 641
 642     if(current_symbol == TERMINATING_RESULT){
 643         result = yylval.token_string;
 644         if(RAV_level == 0){
 645             /* In the interests of skipping any intervening material
 646              * between games, set the lookahead to a dummy token.
 647              */
 648             current_symbol = NO_TOKEN;
 649         }
 650         else{
 651             current_symbol = next_token();
 652         }
 653     }
 654     return result;
 655 }
 656
 657 static void
 658 setup_for_new_game(void)
 659 {
 660     restart_lex_for_new_game();
 661     RAV_level = 0;
 662     game_start_position = get_position();
 663 }
 664
 665         /* Discard any data held in the GameHeader.Tags structure. */
 666 void
 667 free_tags(void)
 668 {   unsigned tag;
 669
 670     for(tag = 0; tag < GameHeader.header_tags_length; tag++){
 671         if(GameHeader.Tags[tag] != NULL){
 672             free(GameHeader.Tags[tag]);
 673             GameHeader.Tags[tag] = NULL;
 674         }
 675     }
 676 }
 677
 678         /* Discard data from a gathered game. */
 679 void
 680 free_string_list(StringList *list)
 681 {   StringList *next;
 682
 683     while(list != NULL){
 684         next = list;
 685         list = list->next;
 686         if(next->str != NULL){
 687             (void) free((void *)next->str);
 688         }
 689         (void) free((void *)next);
 690     }
 691 }
 692
 693 static void
 694 free_comment_list(CommentList *comment_list)
 695 {
 696     while(comment_list != NULL){
 697         CommentList *this_comment = comment_list;
 698
 699         if(comment_list->Comment != NULL){
 700             free_string_list(comment_list->Comment);
 701         }
 702         comment_list = comment_list->next;
 703         (void) free((void *)this_comment);
 704     }
 705 }
 706
 707 static void
 708 free_variation(Variation *variation)
 709 {   Variation *next;
 710
 711     while(variation != NULL){
 712         next = variation;
 713         variation = variation->next;
 714         if(next->prefix_comment != NULL){
 715             free_comment_list(next->prefix_comment);
 716         }
 717         if(next->suffix_comment != NULL){
 718             free_comment_list(next->suffix_comment);
 719         }
 720         if(next->moves != NULL){
 721             (void) free_move_list((void *)next->moves);
 722         }
 723         (void) free((void *)next);
 724     }
 725 }
 726
 727 void
 728 free_move_list(Move *move_list)
 729 {   Move *next;
 730
 731     while(move_list != NULL){
 732         next = move_list;
 733         move_list = move_list->next;
 734         if(next->Nags != NULL){
 735             free_string_list(next->Nags);
 736         }
 737         if(next->Comment != NULL){
 738             free_comment_list(next->Comment);
 739         }
 740         if(next->Variants != NULL){
 741             free_variation(next->Variants);
 742         }
 743         if(next->epd != NULL){
 744             (void) free((void *)next->epd);
 745         }
 746         if(next->bpfen != NULL){
 747             (void) free((void *)next->bpfen);
 748         }
 749         if(next->terminating_result != NULL){
 750             (void) free((void *)next->terminating_result);
 751         }
 752         (void) free((void *)next);
 753     }
 754 }
 755
 756         /* Add str onto the tail of list and
 757          * return the head of the resulting list.
 758          */
 759 StringList *
 760 save_string_list_item(StringList *list,const char *str)
 761 {
 762     if(str != NULL){
 763       StringList *new_item;
 764
 765       new_item = (StringList *)MallocOrDie(sizeof(*new_item));
 766       new_item->str = str;
 767       new_item->next = NULL;
 768       if(list == NULL){
 769           list = new_item;
 770       }
 771       else{
 772           StringList *tail = list;
 773
 774           while(tail->next != NULL){
 775               tail = tail->next;
 776           }
 777           tail->next = new_item;
 778       }
 779     }
 780     return list;
 781 }
 782
 783         /* Append any comments in Comment onto the end of
 784          * any associated with move.
 785          */
 786 void
 787 append_comments_to_move(Move *move,CommentList *Comment)
 788 {
 789     if(Comment != NULL){
 790         /* Add in to the end of any already existing. */
 791         if(move->Comment == NULL){
 792             move->Comment = Comment;
 793         }
 794         else{
 795             /* Add in the final comment to
 796              * the end of any existing for this move.
 797              */
 798             CommentList *tail = move->Comment;
 799
 800             while(tail->next != NULL){
 801                 tail = tail->next;
 802             }
 803             tail->next = Comment;
 804         }
 805     }
 806 }
 807
 808 static void
 809 DealWithGame(Move *move_list)
 810 {   Game current_game;
 811     /* Record whether the game has been printed or not.
 812      * This is used for the case of the -n flag which catches
 813      * all non-printed games.
 814      */
 815     Boolean game_output = FALSE;
 816     /* We need a dummy argument for apply_move_list. */
 817     unsigned plycount;
 818
 819     /* Update the count of how many games handled. */
 820     GlobalState.num_games_processed++;
 821
 822     /* Fill in the information currently known. */
 823     current_game.tags = GameHeader.Tags;
 824     current_game.tags_length = GameHeader.header_tags_length;
 825     current_game.prefix_comment = GameHeader.prefix_comment;
 826     current_game.moves = move_list;
 827     current_game.moves_checked = FALSE;
 828     current_game.moves_ok = FALSE;
 829     current_game.error_ply = 0;
 830     current_game.start_position = game_start_position;
 831
 832     /* Determine whether or not this game is wanted, on the
 833      * basis of the various selection criteria available.
 834      */
 835
 836     /*
 837      * apply_move_list checks out the moves.
 838      * If it returns TRUE as a match, it will also fill in the
 839      *                 current_game.final_hash_value and
 840      *                 current_game.cumulative_hash_value
 841      * fields of current_game so that these can be used in the
 842      * previous_occurance function.
 843      *
 844      * If there are any tag criteria, it will be easy to quickly
 845      * eliminate most games without going through the length
 846      * process of game matching.
 847      *
 848      * If ECO adding is done, the order of checking may cause
 849      * a conflict here since it won't be possible to reject a game
 850      * based on its ECO code unless it already has one.
 851      * Therefore, Check for the ECO tag only after everything else has
 852      * been checked.
 853      */
 854     if(CheckTagDetailsNotECO(current_game.tags,current_game.tags_length) &&
 855              apply_move_list(&current_game,&plycount) &&
 856              check_move_bounds(plycount) &&
 857              check_textual_variations(current_game) &&
 858              check_for_ending(current_game.moves) &&
 859              check_for_only_checkmate(current_game.moves) &&
 860              CheckECOTag(current_game.tags)){
 861         /* If there is no original filename then the game is not a
 862          * duplicate.
 863          */
 864         const char *original_filename = previous_occurance(current_game, plycount);
 865
 866         if((original_filename == NULL) && GlobalState.suppress_originals){
 867             /* Don't output first occurrences. */
 868         }
 869         else if((original_filename == NULL) || !GlobalState.suppress_duplicates){
 870             GlobalState.num_games_matched++;
 871             if(GlobalState.check_only) {
 872                 // We are only checking.
 873                 if(GlobalState.verbose){
 874                     /* Report progress on logfile. */
 875                     report_details(GlobalState.logfile);
 876                 }
 877             }
 878             else if(GlobalState.current_file_type == CHECKFILE){
 879                 /* We are only checking, so don't count this as a matched game. */
 880                 GlobalState.num_games_matched--;
 881             }
 882             else if(GlobalState.matching_game_number > 0 &&
 883                   GlobalState.num_games_matched != GlobalState.matching_game_number) {
 884                 /* This is not the right matching game to be output. */
 885             }
 886             else {
 887                 /* This game is to be kept and output. */
 888                 FILE *outputfile = select_output_file(&GlobalState,
 889                         current_game.tags[ECO_TAG]);
 890
 891                 /* See if we wish to separate out duplicates. */
 892                 if((original_filename != NULL) &&
 893                         (GlobalState.duplicate_file != NULL)){
 894                     static const char *last_input_file = NULL;
 895
 896                     outputfile = GlobalState.duplicate_file;
 897                     if((last_input_file != GlobalState.current_input_file) &&
 898                        (GlobalState.current_input_file != NULL)){
 899                            /* Record which file this and succeeding
 900                             * duplicates come from.
 901                             */
 902                           print_str(outputfile,"{ From: ");
 903                           print_str(outputfile,
 904                                       GlobalState.current_input_file);
 905                           print_str(outputfile," }");
 906                           terminate_line(outputfile);
 907                           last_input_file = GlobalState.current_input_file;
 908                     }
 909                   print_str(outputfile,"{ First found in: ");
 910                   print_str(outputfile,original_filename);
 911                   print_str(outputfile," }");
 912                   terminate_line(outputfile);
 913                 }
 914                 /* Now output what we have. */
 915                 output_game(current_game,outputfile);
 916                 game_output = TRUE;
 917                 if(GlobalState.verbose){
 918                     /* Report progress on logfile. */
 919                     report_details(GlobalState.logfile);
 920                 }
 921             }
 922         }
 923     }
 924     if(!game_output && (GlobalState.non_matching_file != NULL) &&
 925                 GlobalState.current_file_type != CHECKFILE){
 926         /* The user wants to keep everything else. */
 927         if(!current_game.moves_checked){
 928              /* Make sure that the move text is in a reasonable state. */
 929              (void) apply_move_list(&current_game,&plycount);
 930         }
 931         if(current_game.moves_ok || GlobalState.keep_broken_games){
 932             output_game(current_game,GlobalState.non_matching_file);
 933         }
 934     }
 935
 936     /* Game is finished with, so free everything. */
 937     if(GameHeader.prefix_comment != NULL){
 938         free_comment_list(GameHeader.prefix_comment);
 939     }
 940     /* Ensure that the GameHeader's prefix comment is NULL for
 941      * the next game.
 942      */
 943     GameHeader.prefix_comment = NULL;
 944
 945     free_tags();
 946     free_move_list(current_game.moves);
 947     if((GlobalState.num_games_processed % 10) == 0){
 948         fprintf(stderr,"Games: %lu\r",GlobalState.num_games_processed);
 949     }
 950 }
 951
 952 static void
 953 DealWithEcoLine(Move *move_list)
 954 {   Game current_game;
 955     /* We need to know the length of a game to store with the
 956      * hash information as a sanity check.
 957      */
 958     unsigned number_of_half_moves;
 959
 960     /* Fill in the information currently known. */
 961     current_game.tags = GameHeader.Tags;
 962     current_game.tags_length = GameHeader.header_tags_length;
 963     current_game.prefix_comment = GameHeader.prefix_comment;
 964     current_game.moves = move_list;
 965     current_game.moves_checked = FALSE;
 966     current_game.moves_ok = FALSE;
 967     current_game.error_ply = 0;
 968
 969     /* apply_eco_move_list checks out the moves.
 970      * It will also fill in the
 971      *                 current_game.final_hash_value and
 972      *                 current_game.cumulative_hash_value
 973      * fields of current_game.
 974      */
 975     if(apply_eco_move_list(&current_game,&number_of_half_moves)){
 976         if(current_game.moves_ok){
 977             /* Store the ECO code in the appropriate hash location. */
 978             save_eco_details(current_game,number_of_half_moves);
 979         }
 980     }
 981
 982     /* Game is finished with, so free everything. */
 983     if(GameHeader.prefix_comment != NULL){
 984         free_comment_list(GameHeader.prefix_comment);
 985     }
 986     /* Ensure that the GameHeader's prefix comment is NULL for
 987      * the next game.
 988      */
 989     GameHeader.prefix_comment = NULL;
 990
 991     free_tags();
 992     free_move_list(current_game.moves);
 993 }
 994
 995         /* If file_type == ECOFILE we are dealing with a file of ECO
 996          * input rather than a normal game file.
 997          */
 998 int
 999 yyparse(SourceFileType file_type)
1000 {
1001     if(file_type != ECOFILE) {
1002         if(!seek_to_begin()) {
1003             return 1;
1004         }
1005     }
1006     setup_for_new_game();
1007     current_symbol = skip_to_next_game(NO_TOKEN);
1008     ParseOptGameList(file_type);
1009     if(current_symbol == EOF_TOKEN){
1010         /* Ok -- EOF. */
1011         return 0;
1012     }
1013     else if(finished_processing(file_type)) {
1014         /* Ok -- done all we need to. */
1015         return 0;
1016     }
1017     else{
1018         fprintf(GlobalState.logfile,"End of input reached before end of file.\n");
1019         return 1;
1020     }
1021 }
1022