contrib/groff-1.19/src/preproc/pic/pic.y

   1 /* Copyright (C) 1989, 1990, 1991, 1992, 2000, 2001, 2002, 2003, 2004, 2005
   2    Free Software Foundation, Inc.
   3      Written by James Clark (jjc@jclark.com)
   4
   5 This file is part of groff.
   6
   7 groff is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 groff is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License along
  18 with groff; see the file COPYING.  If not, write to the Free Software
  19 Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA. */
  20 %{
  21 #include "pic.h"
  22 #include "ptable.h"
  23 #include "object.h"
  24
  25 extern int delim_flag;
  26 extern void copy_rest_thru(const char *, const char *);
  27 extern void copy_file_thru(const char *, const char *, const char *);
  28 extern void push_body(const char *);
  29 extern void do_for(char *var, double from, double to,
  30                    int by_is_multiplicative, double by, char *body);
  31 extern void do_lookahead();
  32
  33 /* Maximum number of characters produced by printf("%g") */
  34 #define GDIGITS 14
  35
  36 int yylex();
  37 void yyerror(const char *);
  38
  39 void reset(const char *nm);
  40 void reset_all();
  41
  42 place *lookup_label(const char *);
  43 void define_label(const char *label, const place *pl);
  44
  45 direction current_direction;
  46 position current_position;
  47
  48 implement_ptable(place)
  49
  50 PTABLE(place) top_table;
  51
  52 PTABLE(place) *current_table = &top_table;
  53 saved_state *current_saved_state = 0;
  54
  55 object_list olist;
  56
  57 const char *ordinal_postfix(int n);
  58 const char *object_type_name(object_type type);
  59 char *format_number(const char *form, double n);
  60 char *do_sprintf(const char *form, const double *v, int nv);
  61
  62 %}
  63
  64
  65 %union {
  66         char *str;
  67         int n;
  68         double x;
  69         struct { double x, y; } pair;
  70         struct { double x; char *body; } if_data;
  71         struct { char *str; const char *filename; int lineno; } lstr;
  72         struct { double *v; int nv; int maxv; } dv;
  73         struct { double val; int is_multiplicative; } by;
  74         place pl;
  75         object *obj;
  76         corner crn;
  77         path *pth;
  78         object_spec *spec;
  79         saved_state *pstate;
  80         graphics_state state;
  81         object_type obtype;
  82 }
  83
  84 %token <str> LABEL
  85 %token <str> VARIABLE
  86 %token <x> NUMBER
  87 %token <lstr> TEXT
  88 %token <lstr> COMMAND_LINE
  89 %token <str> DELIMITED
  90 %token <n> ORDINAL
  91 %token TH
  92 %token LEFT_ARROW_HEAD
  93 %token RIGHT_ARROW_HEAD
  94 %token DOUBLE_ARROW_HEAD
  95 %token LAST
  96 %token UP
  97 %token DOWN
  98 %token LEFT
  99 %token RIGHT
 100 %token BOX
 101 %token CIRCLE
 102 %token ELLIPSE
 103 %token ARC
 104 %token LINE
 105 %token ARROW
 106 %token MOVE
 107 %token SPLINE
 108 %token HEIGHT
 109 %token RADIUS
 110 %token FIGNAME
 111 %token WIDTH
 112 %token DIAMETER
 113 %token UP
 114 %token DOWN
 115 %token RIGHT
 116 %token LEFT
 117 %token FROM
 118 %token TO
 119 %token AT
 120 %token WITH
 121 %token BY
 122 %token THEN
 123 %token SOLID
 124 %token DOTTED
 125 %token DASHED
 126 %token CHOP
 127 %token SAME
 128 %token INVISIBLE
 129 %token LJUST
 130 %token RJUST
 131 %token ABOVE
 132 %token BELOW
 133 %token OF
 134 %token THE
 135 %token WAY
 136 %token BETWEEN
 137 %token AND
 138 %token HERE
 139 %token DOT_N
 140 %token DOT_E
 141 %token DOT_W
 142 %token DOT_S
 143 %token DOT_NE
 144 %token DOT_SE
 145 %token DOT_NW
 146 %token DOT_SW
 147 %token DOT_C
 148 %token DOT_START
 149 %token DOT_END
 150 %token DOT_X
 151 %token DOT_Y
 152 %token DOT_HT
 153 %token DOT_WID
 154 %token DOT_RAD
 155 %token SIN
 156 %token COS
 157 %token ATAN2
 158 %token LOG
 159 %token EXP
 160 %token SQRT
 161 %token K_MAX
 162 %token K_MIN
 163 %token INT
 164 %token RAND
 165 %token SRAND
 166 %token COPY
 167 %token THRU
 168 %token TOP
 169 %token BOTTOM
 170 %token UPPER
 171 %token LOWER
 172 %token SH
 173 %token PRINT
 174 %token CW
 175 %token CCW
 176 %token FOR
 177 %token DO
 178 %token IF
 179 %token ELSE
 180 %token ANDAND
 181 %token OROR
 182 %token NOTEQUAL
 183 %token EQUALEQUAL
 184 %token LESSEQUAL
 185 %token GREATEREQUAL
 186 %token LEFT_CORNER
 187 %token RIGHT_CORNER
 188 %token NORTH
 189 %token SOUTH
 190 %token EAST
 191 %token WEST
 192 %token CENTER
 193 %token END
 194 %token START
 195 %token RESET
 196 %token UNTIL
 197 %token PLOT
 198 %token THICKNESS
 199 %token FILL
 200 %token COLORED
 201 %token OUTLINED
 202 %token SHADED
 203 %token ALIGNED
 204 %token SPRINTF
 205 %token COMMAND
 206
 207 %token DEFINE
 208 %token UNDEF
 209
 210 %left '.'
 211
 212 /* this ensures that plot 17 "%g" parses as (plot 17 "%g") */
 213 %left PLOT
 214 %left TEXT SPRINTF
 215
 216 /* give text adjustments higher precedence than TEXT, so that
 217 box "foo" above ljust == box ("foo" above ljust)
 218 */
 219
 220 %left LJUST RJUST ABOVE BELOW
 221
 222 %left LEFT RIGHT
 223 /* Give attributes that take an optional expression a higher
 224 precedence than left and right, so that eg `line chop left'
 225 parses properly. */
 226 %left CHOP SOLID DASHED DOTTED UP DOWN FILL COLORED OUTLINED
 227 %left LABEL
 228
 229 %left VARIABLE NUMBER '(' SIN COS ATAN2 LOG EXP SQRT K_MAX K_MIN INT RAND SRAND LAST
 230 %left ORDINAL HERE '`'
 231
 232 %left BOX CIRCLE ELLIPSE ARC LINE ARROW SPLINE '['
 233
 234 /* these need to be lower than '-' */
 235 %left HEIGHT RADIUS WIDTH DIAMETER FROM TO AT THICKNESS
 236
 237 /* these must have higher precedence than CHOP so that `label %prec CHOP'
 238 works */
 239 %left DOT_N DOT_E DOT_W DOT_S DOT_NE DOT_SE DOT_NW DOT_SW DOT_C
 240 %left DOT_START DOT_END TOP BOTTOM LEFT_CORNER RIGHT_CORNER
 241 %left UPPER LOWER NORTH SOUTH EAST WEST CENTER START END
 242
 243 %left ','
 244 %left OROR
 245 %left ANDAND
 246 %left EQUALEQUAL NOTEQUAL
 247 %left '<' '>' LESSEQUAL GREATEREQUAL
 248
 249 %left BETWEEN OF
 250 %left AND
 251
 252 %left '+' '-'
 253 %left '*' '/' '%'
 254 %right '!'
 255 %right '^'
 256
 257 %type <x> expr any_expr text_expr
 258 %type <by> optional_by
 259 %type <pair> expr_pair position_not_place
 260 %type <if_data> simple_if
 261 %type <obj> nth_primitive
 262 %type <crn> corner
 263 %type <pth> path label_path relative_path
 264 %type <pl> place label element element_list middle_element_list
 265 %type <spec> object_spec
 266 %type <pair> position
 267 %type <obtype> object_type
 268 %type <n> optional_ordinal_last ordinal
 269 %type <str> macro_name until
 270 %type <dv> sprintf_args
 271 %type <lstr> text print_args print_arg
 272
 273 %%
 274
 275 top:
 276         optional_separator
 277         | element_list
 278                 {
 279                   if (olist.head)
 280                     print_picture(olist.head);
 281                 }
 282         ;
 283
 284
 285 element_list:
 286         optional_separator middle_element_list optional_separator
 287                 { $$ = $2; }
 288         ;
 289
 290 middle_element_list:
 291         element
 292                 { $$ = $1; }
 293         | middle_element_list separator element
 294                 { $$ = $1; }
 295         ;
 296
 297 optional_separator:
 298         /* empty */
 299         | separator
 300         ;
 301
 302 separator:
 303         ';'
 304         | separator ';'
 305         ;
 306
 307 placeless_element:
 308         FIGNAME '=' macro_name
 309                 {
 310                   a_delete graphname;
 311                   graphname = new char[strlen($3) + 1];
 312                   strcpy(graphname, $3);
 313                   a_delete $3;
 314                 }
 315         |
 316         VARIABLE '=' any_expr
 317                 {
 318                   define_variable($1, $3);
 319                   a_delete $1;
 320                 }
 321         | VARIABLE ':' '=' any_expr
 322                 {
 323                   place *p = lookup_label($1);
 324                   if (!p) {
 325                     lex_error("variable `%1' not defined", $1);
 326                     YYABORT;
 327                   }
 328                   p->obj = 0;
 329                   p->x = $4;
 330                   p->y = 0.0;
 331                   a_delete $1;
 332                 }
 333         | UP
 334                 { current_direction = UP_DIRECTION; }
 335         | DOWN
 336                 { current_direction = DOWN_DIRECTION; }
 337         | LEFT
 338                 { current_direction = LEFT_DIRECTION; }
 339         | RIGHT
 340                 { current_direction = RIGHT_DIRECTION; }
 341         | COMMAND_LINE
 342                 {
 343                   olist.append(make_command_object($1.str, $1.filename,
 344                                                    $1.lineno));
 345                 }
 346         | COMMAND print_args
 347                 {
 348                   olist.append(make_command_object($2.str, $2.filename,
 349                                                    $2.lineno));
 350                 }
 351         | PRINT print_args
 352                 {
 353                   fprintf(stderr, "%s\n", $2.str);
 354                   a_delete $2.str;
 355                   fflush(stderr);
 356                 }
 357         | SH
 358                 { delim_flag = 1; }
 359           DELIMITED
 360                 {
 361                   delim_flag = 0;
 362                   if (safer_flag)
 363                     lex_error("unsafe to run command `%1'", $3);
 364                   else
 365                     system($3);
 366                   a_delete $3;
 367                 }
 368         | COPY TEXT
 369                 {
 370                   if (yychar < 0)
 371                     do_lookahead();
 372                   do_copy($2.str);
 373                   // do not delete the filename
 374                 }
 375         | COPY TEXT THRU
 376                 { delim_flag = 2; }
 377           DELIMITED
 378                 { delim_flag = 0; }
 379           until
 380                 {
 381                   if (yychar < 0)
 382                     do_lookahead();
 383                   copy_file_thru($2.str, $5, $7);
 384                   // do not delete the filename
 385                   a_delete $5;
 386                   a_delete $7;
 387                 }
 388         | COPY THRU
 389                 { delim_flag = 2; }
 390           DELIMITED
 391                 { delim_flag = 0; }
 392           until
 393                 {
 394                   if (yychar < 0)
 395                     do_lookahead();
 396                   copy_rest_thru($4, $6);
 397                   a_delete $4;
 398                   a_delete $6;
 399                 }
 400         | FOR VARIABLE '=' expr TO expr optional_by DO
 401                 { delim_flag = 1; }
 402           DELIMITED
 403                 {
 404                   delim_flag = 0;
 405                   if (yychar < 0)
 406                     do_lookahead();
 407                   do_for($2, $4, $6, $7.is_multiplicative, $7.val, $10);
 408                 }
 409         | simple_if
 410                 {
 411                   if (yychar < 0)
 412                     do_lookahead();
 413                   if ($1.x != 0.0)
 414                     push_body($1.body);
 415                   a_delete $1.body;
 416                 }
 417         | simple_if ELSE
 418                 { delim_flag = 1; }
 419           DELIMITED
 420                 {
 421                   delim_flag = 0;
 422                   if (yychar < 0)
 423                     do_lookahead();
 424                   if ($1.x != 0.0)
 425                     push_body($1.body);
 426                   else
 427                     push_body($4);
 428                   a_delete $1.body;
 429                   a_delete $4;
 430                 }
 431         | reset_variables
 432         | RESET
 433                 { define_variable("scale", 1.0); }
 434         ;
 435
 436 macro_name:
 437         VARIABLE
 438         | LABEL
 439         ;
 440
 441 reset_variables:
 442         RESET VARIABLE
 443                 {
 444                   reset($2);
 445                   a_delete $2;
 446                 }
 447         | reset_variables VARIABLE
 448                 {
 449                   reset($2);
 450                   a_delete $2;
 451                 }
 452         | reset_variables ',' VARIABLE
 453                 {
 454                   reset($3);
 455                   a_delete $3;
 456                 }
 457         ;
 458
 459 print_args:
 460         print_arg
 461                 { $$ = $1; }
 462         | print_args print_arg
 463                 {
 464                   $$.str = new char[strlen($1.str) + strlen($2.str) + 1];
 465                   strcpy($$.str, $1.str);
 466                   strcat($$.str, $2.str);
 467                   a_delete $1.str;
 468                   a_delete $2.str;
 469                   if ($1.filename) {
 470                     $$.filename = $1.filename;
 471                     $$.lineno = $1.lineno;
 472                   }
 473                   else if ($2.filename) {
 474                     $$.filename = $2.filename;
 475                     $$.lineno = $2.lineno;
 476                   }
 477                 }
 478         ;
 479
 480 print_arg:
 481         expr                                                    %prec ','
 482                 {
 483                   $$.str = new char[GDIGITS + 1];
 484                   sprintf($$.str, "%g", $1);
 485                   $$.filename = 0;
 486                   $$.lineno = 0;
 487                 }
 488         | text
 489                 { $$ = $1; }
 490         | position                                              %prec ','
 491                 {
 492                   $$.str = new char[GDIGITS + 2 + GDIGITS + 1];
 493                   sprintf($$.str, "%g, %g", $1.x, $1.y);
 494                   $$.filename = 0;
 495                   $$.lineno = 0;
 496                 }
 497         ;
 498
 499 simple_if:
 500         IF any_expr THEN
 501                 { delim_flag = 1; }
 502         DELIMITED
 503                 {
 504                   delim_flag = 0;
 505                   $$.x = $2;
 506                   $$.body = $5;
 507                 }
 508         ;
 509
 510 until:
 511         /* empty */
 512                 { $$ = 0; }
 513         | UNTIL TEXT
 514                 { $$ = $2.str; }
 515         ;
 516
 517 any_expr:
 518         expr
 519                 { $$ = $1; }
 520         | text_expr
 521                 { $$ = $1; }
 522         ;
 523
 524 text_expr:
 525         text EQUALEQUAL text
 526                 {
 527                   $$ = strcmp($1.str, $3.str) == 0;
 528                   a_delete $1.str;
 529                   a_delete $3.str;
 530                 }
 531         | text NOTEQUAL text
 532                 {
 533                   $$ = strcmp($1.str, $3.str) != 0;
 534                   a_delete $1.str;
 535                   a_delete $3.str;
 536                 }
 537         | text_expr ANDAND text_expr
 538                 { $$ = ($1 != 0.0 && $3 != 0.0); }
 539         | text_expr ANDAND expr
 540                 { $$ = ($1 != 0.0 && $3 != 0.0); }
 541         | expr ANDAND text_expr
 542                 { $$ = ($1 != 0.0 && $3 != 0.0); }
 543         | text_expr OROR text_expr
 544                 { $$ = ($1 != 0.0 || $3 != 0.0); }
 545         | text_expr OROR expr
 546                 { $$ = ($1 != 0.0 || $3 != 0.0); }
 547         | expr OROR text_expr
 548                 { $$ = ($1 != 0.0 || $3 != 0.0); }
 549         | '!' text_expr
 550                 { $$ = ($2 == 0.0); }
 551         ;
 552
 553
 554 optional_by:
 555         /* empty */
 556                 {
 557                   $$.val = 1.0;
 558                   $$.is_multiplicative = 0;
 559                 }
 560         | BY expr
 561                 {
 562                   $$.val = $2;
 563                   $$.is_multiplicative = 0;
 564                 }
 565         | BY '*' expr
 566                 {
 567                   $$.val = $3;
 568                   $$.is_multiplicative = 1;
 569                 }
 570         ;
 571
 572 element:
 573         object_spec
 574                 {
 575                   $$.obj = $1->make_object(&current_position,
 576                                            &current_direction);
 577                   if ($$.obj == 0)
 578                     YYABORT;
 579                   delete $1;
 580                   if ($$.obj)
 581                     olist.append($$.obj);
 582                   else {
 583                     $$.x = current_position.x;
 584                     $$.y = current_position.y;
 585                   }
 586                 }
 587         | LABEL ':' optional_separator element
 588                 {
 589                   $$ = $4;
 590                   define_label($1, & $$);
 591                   a_delete $1;
 592                 }
 593         | LABEL ':' optional_separator position_not_place
 594                 {
 595                   $$.obj = 0;
 596                   $$.x = $4.x;
 597                   $$.y = $4.y;
 598                   define_label($1, & $$);
 599                   a_delete $1;
 600                 }
 601         | LABEL ':' optional_separator place
 602                 {
 603                   $$ = $4;
 604                   define_label($1, & $$);
 605                   a_delete $1;
 606                 }
 607         | '{'
 608                 {
 609                   $<state>$.x = current_position.x;
 610                   $<state>$.y = current_position.y;
 611                   $<state>$.dir = current_direction;
 612                 }
 613           element_list '}'
 614                 {
 615                   current_position.x = $<state>2.x;
 616                   current_position.y = $<state>2.y;
 617                   current_direction = $<state>2.dir;
 618                 }
 619           optional_element
 620                 {
 621                   $$ = $3;
 622                 }
 623         | placeless_element
 624                 {
 625                   $$.obj = 0;
 626                   $$.x = current_position.x;
 627                   $$.y = current_position.y;
 628                 }
 629         ;
 630
 631 optional_element:
 632         /* empty */
 633                 {}
 634         | element
 635                 {}
 636         ;
 637
 638 object_spec:
 639         BOX
 640                 { $$ = new object_spec(BOX_OBJECT); }
 641         | CIRCLE
 642                 { $$ = new object_spec(CIRCLE_OBJECT); }
 643         | ELLIPSE
 644                 { $$ = new object_spec(ELLIPSE_OBJECT); }
 645         | ARC
 646                 {
 647                   $$ = new object_spec(ARC_OBJECT);
 648                   $$->dir = current_direction;
 649                 }
 650         | LINE
 651                 {
 652                   $$ = new object_spec(LINE_OBJECT);
 653                   lookup_variable("lineht", & $$->segment_height);
 654                   lookup_variable("linewid", & $$->segment_width);
 655                   $$->dir = current_direction;
 656                 }
 657         | ARROW
 658                 {
 659                   $$ = new object_spec(ARROW_OBJECT);
 660                   lookup_variable("lineht", & $$->segment_height);
 661                   lookup_variable("linewid", & $$->segment_width);
 662                   $$->dir = current_direction;
 663                 }
 664         | MOVE
 665                 {
 666                   $$ = new object_spec(MOVE_OBJECT);
 667                   lookup_variable("moveht", & $$->segment_height);
 668                   lookup_variable("movewid", & $$->segment_width);
 669                   $$->dir = current_direction;
 670                 }
 671         | SPLINE
 672                 {
 673                   $$ = new object_spec(SPLINE_OBJECT);
 674                   lookup_variable("lineht", & $$->segment_height);
 675                   lookup_variable("linewid", & $$->segment_width);
 676                   $$->dir = current_direction;
 677                 }
 678         | text                                                  %prec TEXT
 679                 {
 680                   $$ = new object_spec(TEXT_OBJECT);
 681                   $$->text = new text_item($1.str, $1.filename, $1.lineno);
 682                 }
 683         | PLOT expr
 684                 {
 685                   $$ = new object_spec(TEXT_OBJECT);
 686                   $$->text = new text_item(format_number(0, $2), 0, -1);
 687                 }
 688         | PLOT expr text
 689                 {
 690                   $$ = new object_spec(TEXT_OBJECT);
 691                   $$->text = new text_item(format_number($3.str, $2),
 692                                            $3.filename, $3.lineno);
 693                   a_delete $3.str;
 694                 }
 695         | '['
 696                 {
 697                   saved_state *p = new saved_state;
 698                   $<pstate>$ = p;
 699                   p->x = current_position.x;
 700                   p->y = current_position.y;
 701                   p->dir = current_direction;
 702                   p->tbl = current_table;
 703                   p->prev = current_saved_state;
 704                   current_position.x = 0.0;
 705                   current_position.y = 0.0;
 706                   current_table = new PTABLE(place);
 707                   current_saved_state = p;
 708                   olist.append(make_mark_object());
 709                 }
 710           element_list ']'
 711                 {
 712                   current_position.x = $<pstate>2->x;
 713                   current_position.y = $<pstate>2->y;
 714                   current_direction = $<pstate>2->dir;
 715                   $$ = new object_spec(BLOCK_OBJECT);
 716                   olist.wrap_up_block(& $$->oblist);
 717                   $$->tbl = current_table;
 718                   current_table = $<pstate>2->tbl;
 719                   current_saved_state = $<pstate>2->prev;
 720                   delete $<pstate>2;
 721                 }
 722         | object_spec HEIGHT expr
 723                 {
 724                   $$ = $1;
 725                   $$->height = $3;
 726                   $$->flags |= HAS_HEIGHT;
 727                 }
 728         | object_spec RADIUS expr
 729                 {
 730                   $$ = $1;
 731                   $$->radius = $3;
 732                   $$->flags |= HAS_RADIUS;
 733                 }
 734         | object_spec WIDTH expr
 735                 {
 736                   $$ = $1;
 737                   $$->width = $3;
 738                   $$->flags |= HAS_WIDTH;
 739                 }
 740         | object_spec DIAMETER expr
 741                 {
 742                   $$ = $1;
 743                   $$->radius = $3/2.0;
 744                   $$->flags |= HAS_RADIUS;
 745                 }
 746         | object_spec expr                                      %prec HEIGHT
 747                 {
 748                   $$ = $1;
 749                   $$->flags |= HAS_SEGMENT;
 750                   switch ($$->dir) {
 751                   case UP_DIRECTION:
 752                     $$->segment_pos.y += $2;
 753                     break;
 754                   case DOWN_DIRECTION:
 755                     $$->segment_pos.y -= $2;
 756                     break;
 757                   case RIGHT_DIRECTION:
 758                     $$->segment_pos.x += $2;
 759                     break;
 760                   case LEFT_DIRECTION:
 761                     $$->segment_pos.x -= $2;
 762                     break;
 763                   }
 764                 }
 765         | object_spec UP
 766                 {
 767                   $$ = $1;
 768                   $$->dir = UP_DIRECTION;
 769                   $$->flags |= HAS_SEGMENT;
 770                   $$->segment_pos.y += $$->segment_height;
 771                 }
 772         | object_spec UP expr
 773                 {
 774                   $$ = $1;
 775                   $$->dir = UP_DIRECTION;
 776                   $$->flags |= HAS_SEGMENT;
 777                   $$->segment_pos.y += $3;
 778                 }
 779         | object_spec DOWN
 780                 {
 781                   $$ = $1;
 782                   $$->dir = DOWN_DIRECTION;
 783                   $$->flags |= HAS_SEGMENT;
 784                   $$->segment_pos.y -= $$->segment_height;
 785                 }
 786         | object_spec DOWN expr
 787                 {
 788                   $$ = $1;
 789                   $$->dir = DOWN_DIRECTION;
 790                   $$->flags |= HAS_SEGMENT;
 791                   $$->segment_pos.y -= $3;
 792                 }
 793         | object_spec RIGHT
 794                 {
 795                   $$ = $1;
 796                   $$->dir = RIGHT_DIRECTION;
 797                   $$->flags |= HAS_SEGMENT;
 798                   $$->segment_pos.x += $$->segment_width;
 799                 }
 800         | object_spec RIGHT expr
 801                 {
 802                   $$ = $1;
 803                   $$->dir = RIGHT_DIRECTION;
 804                   $$->flags |= HAS_SEGMENT;
 805                   $$->segment_pos.x += $3;
 806                 }
 807         | object_spec LEFT
 808                 {
 809                   $$ = $1;
 810                   $$->dir = LEFT_DIRECTION;
 811                   $$->flags |= HAS_SEGMENT;
 812                   $$->segment_pos.x -= $$->segment_width;
 813                 }
 814         | object_spec LEFT expr
 815                 {
 816                   $$ = $1;
 817                   $$->dir = LEFT_DIRECTION;
 818                   $$->flags |= HAS_SEGMENT;
 819                   $$->segment_pos.x -= $3;
 820                 }
 821         | object_spec FROM position
 822                 {
 823                   $$ = $1;
 824                   $$->flags |= HAS_FROM;
 825                   $$->from.x = $3.x;
 826                   $$->from.y = $3.y;
 827                 }
 828         | object_spec TO position
 829                 {
 830                   $$ = $1;
 831                   if ($$->flags & HAS_SEGMENT)
 832                     $$->segment_list = new segment($$->segment_pos,
 833                                                    $$->segment_is_absolute,
 834                                                    $$->segment_list);
 835                   $$->flags |= HAS_SEGMENT;
 836                   $$->segment_pos.x = $3.x;
 837                   $$->segment_pos.y = $3.y;
 838                   $$->segment_is_absolute = 1;
 839                   $$->flags |= HAS_TO;
 840                   $$->to.x = $3.x;
 841                   $$->to.y = $3.y;
 842                 }
 843         | object_spec AT position
 844                 {
 845                   $$ = $1;
 846                   $$->flags |= HAS_AT;
 847                   $$->at.x = $3.x;
 848                   $$->at.y = $3.y;
 849                   if ($$->type != ARC_OBJECT) {
 850                     $$->flags |= HAS_FROM;
 851                     $$->from.x = $3.x;
 852                     $$->from.y = $3.y;
 853                   }
 854                 }
 855         | object_spec WITH path
 856                 {
 857                   $$ = $1;
 858                   $$->flags |= HAS_WITH;
 859                   $$->with = $3;
 860                 }
 861         | object_spec WITH position                             %prec ','
 862                 {
 863                   $$ = $1;
 864                   $$->flags |= HAS_WITH;
 865                   position pos;
 866                   pos.x = $3.x;
 867                   pos.y = $3.y;
 868                   $$->with = new path(pos);
 869                 }
 870         | object_spec BY expr_pair
 871                 {
 872                   $$ = $1;
 873                   $$->flags |= HAS_SEGMENT;
 874                   $$->segment_pos.x += $3.x;
 875                   $$->segment_pos.y += $3.y;
 876                 }
 877         | object_spec THEN
 878                 {
 879                   $$ = $1;
 880                   if ($$->flags & HAS_SEGMENT) {
 881                     $$->segment_list = new segment($$->segment_pos,
 882                                                    $$->segment_is_absolute,
 883                                                    $$->segment_list);
 884                     $$->flags &= ~HAS_SEGMENT;
 885                     $$->segment_pos.x = $$->segment_pos.y = 0.0;
 886                     $$->segment_is_absolute = 0;
 887                   }
 888                 }
 889         | object_spec SOLID
 890                 {
 891                   $$ = $1;      // nothing
 892                 }
 893         | object_spec DOTTED
 894                 {
 895                   $$ = $1;
 896                   $$->flags |= IS_DOTTED;
 897                   lookup_variable("dashwid", & $$->dash_width);
 898                 }
 899         | object_spec DOTTED expr
 900                 {
 901                   $$ = $1;
 902                   $$->flags |= IS_DOTTED;
 903                   $$->dash_width = $3;
 904                 }
 905         | object_spec DASHED
 906                 {
 907                   $$ = $1;
 908                   $$->flags |= IS_DASHED;
 909                   lookup_variable("dashwid", & $$->dash_width);
 910                 }
 911         | object_spec DASHED expr
 912                 {
 913                   $$ = $1;
 914                   $$->flags |= IS_DASHED;
 915                   $$->dash_width = $3;
 916                 }
 917         | object_spec FILL
 918                 {
 919                   $$ = $1;
 920                   $$->flags |= IS_DEFAULT_FILLED;
 921                 }
 922         | object_spec FILL expr
 923                 {
 924                   $$ = $1;
 925                   $$->flags |= IS_FILLED;
 926                   $$->fill = $3;
 927                 }
 928         | object_spec SHADED text
 929                 {
 930                   $$ = $1;
 931                   $$->flags |= (IS_SHADED | IS_FILLED);
 932                   $$->shaded = new char[strlen($3.str)+1];
 933                   strcpy($$->shaded, $3.str);
 934                 }
 935         | object_spec COLORED text
 936                 {
 937                   $$ = $1;
 938                   $$->flags |= (IS_SHADED | IS_OUTLINED | IS_FILLED);
 939                   $$->shaded = new char[strlen($3.str)+1];
 940                   strcpy($$->shaded, $3.str);
 941                   $$->outlined = new char[strlen($3.str)+1];
 942                   strcpy($$->outlined, $3.str);
 943                 }
 944         | object_spec OUTLINED text
 945                 {
 946                   $$ = $1;
 947                   $$->flags |= IS_OUTLINED;
 948                   $$->outlined = new char[strlen($3.str)+1];
 949                   strcpy($$->outlined, $3.str);
 950                 }
 951         | object_spec CHOP
 952                 {
 953                   $$ = $1;
 954                   // line chop chop means line chop 0 chop 0
 955                   if ($$->flags & IS_DEFAULT_CHOPPED) {
 956                     $$->flags |= IS_CHOPPED;
 957                     $$->flags &= ~IS_DEFAULT_CHOPPED;
 958                     $$->start_chop = $$->end_chop = 0.0;
 959                   }
 960                   else if ($$->flags & IS_CHOPPED) {
 961                     $$->end_chop = 0.0;
 962                   }
 963                   else {
 964                     $$->flags |= IS_DEFAULT_CHOPPED;
 965                   }
 966                 }
 967         | object_spec CHOP expr
 968                 {
 969                   $$ = $1;
 970                   if ($$->flags & IS_DEFAULT_CHOPPED) {
 971                     $$->flags |= IS_CHOPPED;
 972                     $$->flags &= ~IS_DEFAULT_CHOPPED;
 973                     $$->start_chop = 0.0;
 974                     $$->end_chop = $3;
 975                   }
 976                   else if ($$->flags & IS_CHOPPED) {
 977                     $$->end_chop = $3;
 978                   }
 979                   else {
 980                     $$->start_chop = $$->end_chop = $3;
 981                     $$->flags |= IS_CHOPPED;
 982                   }
 983                 }
 984         | object_spec SAME
 985                 {
 986                   $$ = $1;
 987                   $$->flags |= IS_SAME;
 988                 }
 989         | object_spec INVISIBLE
 990                 {
 991                   $$ = $1;
 992                   $$->flags |= IS_INVISIBLE;
 993                 }
 994         | object_spec LEFT_ARROW_HEAD
 995                 {
 996                   $$ = $1;
 997                   $$->flags |= HAS_LEFT_ARROW_HEAD;
 998                 }
 999         | object_spec RIGHT_ARROW_HEAD
1000                 {
1001                   $$ = $1;
1002                   $$->flags |= HAS_RIGHT_ARROW_HEAD;
1003                 }
1004         | object_spec DOUBLE_ARROW_HEAD
1005                 {
1006                   $$ = $1;
1007                   $$->flags |= (HAS_LEFT_ARROW_HEAD|HAS_RIGHT_ARROW_HEAD);
1008                 }
1009         | object_spec CW
1010                 {
1011                   $$ = $1;
1012                   $$->flags |= IS_CLOCKWISE;
1013                 }
1014         | object_spec CCW
1015                 {
1016                   $$ = $1;
1017                   $$->flags &= ~IS_CLOCKWISE;
1018                 }
1019         | object_spec text                                      %prec TEXT
1020                 {
1021                   $$ = $1;
1022                   text_item **p;
1023                   for (p = & $$->text; *p; p = &(*p)->next)
1024                     ;
1025                   *p = new text_item($2.str, $2.filename, $2.lineno);
1026                 }
1027         | object_spec LJUST
1028                 {
1029                   $$ = $1;
1030                   if ($$->text) {
1031                     text_item *p;
1032                     for (p = $$->text; p->next; p = p->next)
1033                       ;
1034                     p->adj.h = LEFT_ADJUST;
1035                   }
1036                 }
1037         | object_spec RJUST
1038                 {
1039                   $$ = $1;
1040                   if ($$->text) {
1041                     text_item *p;
1042                     for (p = $$->text; p->next; p = p->next)
1043                       ;
1044                     p->adj.h = RIGHT_ADJUST;
1045                   }
1046                 }
1047         | object_spec ABOVE
1048                 {
1049                   $$ = $1;
1050                   if ($$->text) {
1051                     text_item *p;
1052                     for (p = $$->text; p->next; p = p->next)
1053                       ;
1054                     p->adj.v = ABOVE_ADJUST;
1055                   }
1056                 }
1057         | object_spec BELOW
1058                 {
1059                   $$ = $1;
1060                   if ($$->text) {
1061                     text_item *p;
1062                     for (p = $$->text; p->next; p = p->next)
1063                       ;
1064                     p->adj.v = BELOW_ADJUST;
1065                   }
1066                 }
1067         | object_spec THICKNESS expr
1068                 {
1069                   $$ = $1;
1070                   $$->flags |= HAS_THICKNESS;
1071                   $$->thickness = $3;
1072                 }
1073         | object_spec ALIGNED
1074                 {
1075                   $$ = $1;
1076                   $$->flags |= IS_ALIGNED;
1077                 }
1078         ;
1079
1080 text:
1081         TEXT
1082                 { $$ = $1; }
1083         | SPRINTF '(' TEXT sprintf_args ')'
1084                 {
1085                   $$.filename = $3.filename;
1086                   $$.lineno = $3.lineno;
1087                   $$.str = do_sprintf($3.str, $4.v, $4.nv);
1088                   a_delete $4.v;
1089                   a_delete $3.str;
1090                 }
1091         ;
1092
1093 sprintf_args:
1094         /* empty */
1095                 {
1096                   $$.v = 0;
1097                   $$.nv = 0;
1098                   $$.maxv = 0;
1099                 }
1100         | sprintf_args ',' expr
1101                 {
1102                   $$ = $1;
1103                   if ($$.nv >= $$.maxv) {
1104                     if ($$.nv == 0) {
1105                       $$.v = new double[4];
1106                       $$.maxv = 4;
1107                     }
1108                     else {
1109                       double *oldv = $$.v;
1110                       $$.maxv *= 2;
1111 #if 0
1112                       $$.v = new double[$$.maxv];
1113                       memcpy($$.v, oldv, $$.nv*sizeof(double));
1114 #else
1115                       // workaround for bug in Compaq C++ V6.5-033
1116                       // for Compaq Tru64 UNIX V5.1A (Rev. 1885)
1117                       double *foo = new double[$$.maxv];
1118                       memcpy(foo, oldv, $$.nv*sizeof(double));
1119                       $$.v = foo;
1120 #endif
1121                       a_delete oldv;
1122                     }
1123                   }
1124                   $$.v[$$.nv] = $3;
1125                   $$.nv += 1;
1126                 }
1127         ;
1128
1129 position:
1130         position_not_place
1131                 { $$ = $1; }
1132         | place
1133                 {
1134                   position pos = $1;
1135                   $$.x = pos.x;
1136                   $$.y = pos.y;
1137                 }
1138         | '(' place ')'
1139                 {
1140                   position pos = $2;
1141                   $$.x = pos.x;
1142                   $$.y = pos.y;
1143                 }
1144         ;
1145
1146 position_not_place:
1147         expr_pair
1148                 { $$ = $1; }
1149         | position '+' expr_pair
1150                 {
1151                   $$.x = $1.x + $3.x;
1152                   $$.y = $1.y + $3.y;
1153                 }
1154         | '(' position '+' expr_pair ')'
1155                 {
1156                   $$.x = $2.x + $4.x;
1157                   $$.y = $2.y + $4.y;
1158                 }
1159         | position '-' expr_pair
1160                 {
1161                   $$.x = $1.x - $3.x;
1162                   $$.y = $1.y - $3.y;
1163                 }
1164         | '(' position '-' expr_pair ')'
1165                 {
1166                   $$.x = $2.x - $4.x;
1167                   $$.y = $2.y - $4.y;
1168                 }
1169         | '(' position ',' position ')'
1170                 {
1171                   $$.x = $2.x;
1172                   $$.y = $4.y;
1173                 }
1174         | expr between position AND position
1175                 {
1176                   $$.x = (1.0 - $1)*$3.x + $1*$5.x;
1177                   $$.y = (1.0 - $1)*$3.y + $1*$5.y;
1178                 }
1179         | '(' expr between position AND position ')'
1180                 {
1181                   $$.x = (1.0 - $2)*$4.x + $2*$6.x;
1182                   $$.y = (1.0 - $2)*$4.y + $2*$6.y;
1183                 }
1184         | expr '<' position ',' position '>'
1185                 {
1186                   $$.x = (1.0 - $1)*$3.x + $1*$5.x;
1187                   $$.y = (1.0 - $1)*$3.y + $1*$5.y;
1188                 }
1189         | '(' expr '<' position ',' position '>' ')'
1190                 {
1191                   $$.x = (1.0 - $2)*$4.x + $2*$6.x;
1192                   $$.y = (1.0 - $2)*$4.y + $2*$6.y;
1193                 }
1194         ;
1195
1196 between:
1197         BETWEEN
1198         | OF THE WAY BETWEEN
1199         ;
1200
1201 expr_pair:
1202         expr ',' expr
1203                 {
1204                   $$.x = $1;
1205                   $$.y = $3;
1206                 }
1207         | '(' expr_pair ')'
1208                 { $$ = $2; }
1209         ;
1210
1211 place:
1212         /* line at A left == line (at A) left */
1213         label                                                   %prec CHOP
1214                 { $$ = $1; }
1215         | label corner
1216                 {
1217                   path pth($2);
1218                   if (!pth.follow($1, & $$))
1219                     YYABORT;
1220                 }
1221         | corner label
1222                 {
1223                   path pth($1);
1224                   if (!pth.follow($2, & $$))
1225                     YYABORT;
1226                 }
1227         | corner OF label
1228                 {
1229                   path pth($1);
1230                   if (!pth.follow($3, & $$))
1231                     YYABORT;
1232                 }
1233         | HERE
1234                 {
1235                   $$.x = current_position.x;
1236                   $$.y = current_position.y;
1237                   $$.obj = 0;
1238                 }
1239         ;
1240
1241 label:
1242         LABEL
1243                 {
1244                   place *p = lookup_label($1);
1245                   if (!p) {
1246                     lex_error("there is no place `%1'", $1);
1247                     YYABORT;
1248                   }
1249                   $$ = *p;
1250                   a_delete $1;
1251                 }
1252         | nth_primitive
1253                 { $$.obj = $1; }
1254         | label '.' LABEL
1255                 {
1256                   path pth($3);
1257                   if (!pth.follow($1, & $$))
1258                     YYABORT;
1259                 }
1260         ;
1261
1262 ordinal:
1263         ORDINAL
1264                 { $$ = $1; }
1265         | '`' any_expr TH
1266                 {
1267                   // XXX Check for overflow (and non-integers?).
1268                   $$ = (int)$2;
1269                 }
1270         ;
1271
1272 optional_ordinal_last:
1273         LAST
1274                 { $$ = 1; }
1275         | ordinal LAST
1276                 { $$ = $1; }
1277         ;
1278
1279 nth_primitive:
1280         ordinal object_type
1281                 {
1282                   int count = 0;
1283                   object *p;
1284                   for (p = olist.head; p != 0; p = p->next)
1285                     if (p->type() == $2 && ++count == $1) {
1286                       $$ = p;
1287                       break;
1288                     }
1289                   if (p == 0) {
1290                     lex_error("there is no %1%2 %3", $1, ordinal_postfix($1),
1291                               object_type_name($2));
1292                     YYABORT;
1293                   }
1294                 }
1295         | optional_ordinal_last object_type
1296                 {
1297                   int count = 0;
1298                   object *p;
1299                   for (p = olist.tail; p != 0; p = p->prev)
1300                     if (p->type() == $2 && ++count == $1) {
1301                       $$ = p;
1302                       break;
1303                     }
1304                   if (p == 0) {
1305                     lex_error("there is no %1%2 last %3", $1,
1306                               ordinal_postfix($1), object_type_name($2));
1307                     YYABORT;
1308                   }
1309                 }
1310         ;
1311
1312 object_type:
1313         BOX
1314                 { $$ = BOX_OBJECT; }
1315         | CIRCLE
1316                 { $$ = CIRCLE_OBJECT; }
1317         | ELLIPSE
1318                 { $$ = ELLIPSE_OBJECT; }
1319         | ARC
1320                 { $$ = ARC_OBJECT; }
1321         | LINE
1322                 { $$ = LINE_OBJECT; }
1323         | ARROW
1324                 { $$ = ARROW_OBJECT; }
1325         | SPLINE
1326                 { $$ = SPLINE_OBJECT; }
1327         | '[' ']'
1328                 { $$ = BLOCK_OBJECT; }
1329         | TEXT
1330                 { $$ = TEXT_OBJECT; }
1331         ;
1332
1333 label_path:
1334         '.' LABEL
1335                 { $$ = new path($2); }
1336         | label_path '.' LABEL
1337                 {
1338                   $$ = $1;
1339                   $$->append($3);
1340                 }
1341         ;
1342
1343 relative_path:
1344         corner                                                  %prec CHOP
1345                 { $$ = new path($1); }
1346         /* give this a lower precedence than LEFT and RIGHT so that
1347            [A: box] with .A left == [A: box] with (.A left) */
1348         | label_path                                            %prec TEXT
1349                 { $$ = $1; }
1350         | label_path corner
1351                 {
1352                   $$ = $1;
1353                   $$->append($2);
1354                 }
1355         ;
1356
1357 path:
1358         relative_path
1359                 { $$ = $1; }
1360         | '(' relative_path ',' relative_path ')'
1361                 {
1362                   $$ = $2;
1363                   $$->set_ypath($4);
1364                 }
1365         /* The rest of these rules are a compatibility sop. */
1366         | ORDINAL LAST object_type relative_path
1367                 {
1368                   lex_warning("`%1%2 last %3' in `with' argument ignored",
1369                               $1, ordinal_postfix($1), object_type_name($3));
1370                   $$ = $4;
1371                 }
1372         | LAST object_type relative_path
1373                 {
1374                   lex_warning("`last %1' in `with' argument ignored",
1375                               object_type_name($2));
1376                   $$ = $3;
1377                 }
1378         | ORDINAL object_type relative_path
1379                 {
1380                   lex_warning("`%1%2 %3' in `with' argument ignored",
1381                               $1, ordinal_postfix($1), object_type_name($2));
1382                   $$ = $3;
1383                 }
1384         | LABEL relative_path
1385                 {
1386                   lex_warning("initial `%1' in `with' argument ignored", $1);
1387                   a_delete $1;
1388                   $$ = $2;
1389                 }
1390         ;
1391
1392 corner:
1393         DOT_N
1394                 { $$ = &object::north; }
1395         | DOT_E
1396                 { $$ = &object::east; }
1397         | DOT_W
1398                 { $$ = &object::west; }
1399         | DOT_S
1400                 { $$ = &object::south; }
1401         | DOT_NE
1402                 { $$ = &object::north_east; }
1403         | DOT_SE
1404                 { $$ = &object:: south_east; }
1405         | DOT_NW
1406                 { $$ = &object::north_west; }
1407         | DOT_SW
1408                 { $$ = &object::south_west; }
1409         | DOT_C
1410                 { $$ = &object::center; }
1411         | DOT_START
1412                 { $$ = &object::start; }
1413         | DOT_END
1414                 { $$ = &object::end; }
1415         | TOP
1416                 { $$ = &object::north; }
1417         | BOTTOM
1418                 { $$ = &object::south; }
1419         | LEFT
1420                 { $$ = &object::west; }
1421         | RIGHT
1422                 { $$ = &object::east; }
1423         | UPPER LEFT
1424                 { $$ = &object::north_west; }
1425         | LOWER LEFT
1426                 { $$ = &object::south_west; }
1427         | UPPER RIGHT
1428                 { $$ = &object::north_east; }
1429         | LOWER RIGHT
1430                 { $$ = &object::south_east; }
1431         | LEFT_CORNER
1432                 { $$ = &object::west; }
1433         | RIGHT_CORNER
1434                 { $$ = &object::east; }
1435         | UPPER LEFT_CORNER
1436                 { $$ = &object::north_west; }
1437         | LOWER LEFT_CORNER
1438                 { $$ = &object::south_west; }
1439         | UPPER RIGHT_CORNER
1440                 { $$ = &object::north_east; }
1441         | LOWER RIGHT_CORNER
1442                 { $$ = &object::south_east; }
1443         | NORTH
1444                 { $$ = &object::north; }
1445         | SOUTH
1446                 { $$ = &object::south; }
1447         | EAST
1448                 { $$ = &object::east; }
1449         | WEST
1450                 { $$ = &object::west; }
1451         | CENTER
1452                 { $$ = &object::center; }
1453         | START
1454                 { $$ = &object::start; }
1455         | END
1456                 { $$ = &object::end; }
1457         ;
1458
1459 expr:
1460         VARIABLE
1461                 {
1462                   if (!lookup_variable($1, & $$)) {
1463                     lex_error("there is no variable `%1'", $1);
1464                     YYABORT;
1465                   }
1466                   a_delete $1;
1467                 }
1468         | NUMBER
1469                 { $$ = $1; }
1470         | place DOT_X
1471                 {
1472                   if ($1.obj != 0)
1473                     $$ = $1.obj->origin().x;
1474                   else
1475                     $$ = $1.x;
1476                 }
1477         | place DOT_Y
1478                 {
1479                   if ($1.obj != 0)
1480                     $$ = $1.obj->origin().y;
1481                   else
1482                     $$ = $1.y;
1483                 }
1484         | place DOT_HT
1485                 {
1486                   if ($1.obj != 0)
1487                     $$ = $1.obj->height();
1488                   else
1489                     $$ = 0.0;
1490                 }
1491         | place DOT_WID
1492                 {
1493                   if ($1.obj != 0)
1494                     $$ = $1.obj->width();
1495                   else
1496                     $$ = 0.0;
1497                 }
1498         | place DOT_RAD
1499                 {
1500                   if ($1.obj != 0)
1501                     $$ = $1.obj->radius();
1502                   else
1503                     $$ = 0.0;
1504                 }
1505         | expr '+' expr
1506                 { $$ = $1 + $3; }
1507         | expr '-' expr
1508                 { $$ = $1 - $3; }
1509         | expr '*' expr
1510                 { $$ = $1 * $3; }
1511         | expr '/' expr
1512                 {
1513                   if ($3 == 0.0) {
1514                     lex_error("division by zero");
1515                     YYABORT;
1516                   }
1517                   $$ = $1/$3;
1518                 }
1519         | expr '%' expr
1520                 {
1521                   if ($3 == 0.0) {
1522                     lex_error("modulus by zero");
1523                     YYABORT;
1524                   }
1525                   $$ = fmod($1, $3);
1526                 }
1527         | expr '^' expr
1528                 {
1529                   errno = 0;
1530                   $$ = pow($1, $3);
1531                   if (errno == EDOM) {
1532                     lex_error("arguments to `^' operator out of domain");
1533                     YYABORT;
1534                   }
1535                   if (errno == ERANGE) {
1536                     lex_error("result of `^' operator out of range");
1537                     YYABORT;
1538                   }
1539                 }
1540         | '-' expr                                              %prec '!'
1541                 { $$ = -$2; }
1542         | '(' any_expr ')'
1543                 { $$ = $2; }
1544         | SIN '(' any_expr ')'
1545                 {
1546                   errno = 0;
1547                   $$ = sin($3);
1548                   if (errno == ERANGE) {
1549                     lex_error("sin result out of range");
1550                     YYABORT;
1551                   }
1552                 }
1553         | COS '(' any_expr ')'
1554                 {
1555                   errno = 0;
1556                   $$ = cos($3);
1557                   if (errno == ERANGE) {
1558                     lex_error("cos result out of range");
1559                     YYABORT;
1560                   }
1561                 }
1562         | ATAN2 '(' any_expr ',' any_expr ')'
1563                 {
1564                   errno = 0;
1565                   $$ = atan2($3, $5);
1566                   if (errno == EDOM) {
1567                     lex_error("atan2 argument out of domain");
1568                     YYABORT;
1569                   }
1570                   if (errno == ERANGE) {
1571                     lex_error("atan2 result out of range");
1572                     YYABORT;
1573                   }
1574                 }
1575         | LOG '(' any_expr ')'
1576                 {
1577                   errno = 0;
1578                   $$ = log10($3);
1579                   if (errno == ERANGE) {
1580                     lex_error("log result out of range");
1581                     YYABORT;
1582                   }
1583                 }
1584         | EXP '(' any_expr ')'
1585                 {
1586                   errno = 0;
1587                   $$ = pow(10.0, $3);
1588                   if (errno == ERANGE) {
1589                     lex_error("exp result out of range");
1590                     YYABORT;
1591                   }
1592                 }
1593         | SQRT '(' any_expr ')'
1594                 {
1595                   errno = 0;
1596                   $$ = sqrt($3);
1597                   if (errno == EDOM) {
1598                     lex_error("sqrt argument out of domain");
1599                     YYABORT;
1600                   }
1601                 }
1602         | K_MAX '(' any_expr ',' any_expr ')'
1603                 { $$ = $3 > $5 ? $3 : $5; }
1604         | K_MIN '(' any_expr ',' any_expr ')'
1605                 { $$ = $3 < $5 ? $3 : $5; }
1606         | INT '(' any_expr ')'
1607                 { $$ = floor($3); }
1608         | RAND '(' any_expr ')'
1609                 { $$ = 1.0 + floor(((rand()&0x7fff)/double(0x7fff))*$3); }
1610         | RAND '(' ')'
1611                 {
1612                   /* return a random number in the range [0,1) */
1613                   /* portable, but not very random */
1614                   $$ = (rand() & 0x7fff) / double(0x8000);
1615                 }
1616         | SRAND '(' any_expr ')'
1617                 {
1618                   $$ = 0;
1619                   srand((unsigned int)$3);
1620                 }
1621         | expr '<' expr
1622                 { $$ = ($1 < $3); }
1623         | expr LESSEQUAL expr
1624                 { $$ = ($1 <= $3); }
1625         | expr '>' expr
1626                 { $$ = ($1 > $3); }
1627         | expr GREATEREQUAL expr
1628                 { $$ = ($1 >= $3); }
1629         | expr EQUALEQUAL expr
1630                 { $$ = ($1 == $3); }
1631         | expr NOTEQUAL expr
1632                 { $$ = ($1 != $3); }
1633         | expr ANDAND expr
1634                 { $$ = ($1 != 0.0 && $3 != 0.0); }
1635         | expr OROR expr
1636                 { $$ = ($1 != 0.0 || $3 != 0.0); }
1637         | '!' expr
1638                 { $$ = ($2 == 0.0); }
1639
1640         ;
1641
1642 %%
1643
1644 /* bison defines const to be empty unless __STDC__ is defined, which it
1645 isn't under cfront */
1646
1647 #ifdef const
1648 #undef const
1649 #endif
1650
1651 static struct {
1652   const char *name;
1653   double val;
1654   int scaled;                // non-zero if val should be multiplied by scale
1655 } defaults_table[] = {
1656   { "arcrad", .25, 1 },
1657   { "arrowht", .1, 1 },
1658   { "arrowwid", .05, 1 },
1659   { "circlerad", .25, 1 },
1660   { "boxht", .5, 1 },
1661   { "boxwid", .75, 1 },
1662   { "boxrad", 0.0, 1 },
1663   { "dashwid", .05, 1 },
1664   { "ellipseht", .5, 1 },
1665   { "ellipsewid", .75, 1 },
1666   { "moveht", .5, 1 },
1667   { "movewid", .5, 1 },
1668   { "lineht", .5, 1 },
1669   { "linewid", .5, 1 },
1670   { "textht", 0.0, 1 },
1671   { "textwid", 0.0, 1 },
1672   { "scale", 1.0, 0 },
1673   { "linethick", -1.0, 0 },             // in points
1674   { "fillval", .5, 0 },
1675   { "arrowhead", 1.0, 0 },
1676   { "maxpswid", 8.5, 0 },
1677   { "maxpsht", 11.0, 0 },
1678 };
1679
1680 place *lookup_label(const char *label)
1681 {
1682   saved_state *state = current_saved_state;
1683   PTABLE(place) *tbl = current_table;
1684   for (;;) {
1685     place *pl = tbl->lookup(label);
1686     if (pl)
1687       return pl;
1688     if (!state)
1689       return 0;
1690     tbl = state->tbl;
1691     state = state->prev;
1692   }
1693 }
1694
1695 void define_label(const char *label, const place *pl)
1696 {
1697   place *p = new place[1];
1698   *p = *pl;
1699   current_table->define(label, p);
1700 }
1701
1702 int lookup_variable(const char *name, double *val)
1703 {
1704   place *pl = lookup_label(name);
1705   if (pl) {
1706     *val = pl->x;
1707     return 1;
1708   }
1709   return 0;
1710 }
1711
1712 void define_variable(const char *name, double val)
1713 {
1714   place *p = new place[1];
1715   p->obj = 0;
1716   p->x = val;
1717   p->y = 0.0;
1718   current_table->define(name, p);
1719   if (strcmp(name, "scale") == 0) {
1720     // When the scale changes, reset all scaled pre-defined variables to
1721     // their default values.
1722     for (unsigned int i = 0;
1723          i < sizeof(defaults_table)/sizeof(defaults_table[0]); i++)
1724       if (defaults_table[i].scaled)
1725         define_variable(defaults_table[i].name, val*defaults_table[i].val);
1726   }
1727 }
1728
1729 // called once only (not once per parse)
1730
1731 void parse_init()
1732 {
1733   current_direction = RIGHT_DIRECTION;
1734   current_position.x = 0.0;
1735   current_position.y = 0.0;
1736   // This resets everything to its default value.
1737   reset_all();
1738 }
1739
1740 void reset(const char *nm)
1741 {
1742   for (unsigned int i = 0;
1743        i < sizeof(defaults_table)/sizeof(defaults_table[0]); i++)
1744     if (strcmp(nm, defaults_table[i].name) == 0) {
1745       double val = defaults_table[i].val;
1746       if (defaults_table[i].scaled) {
1747         double scale;
1748         lookup_variable("scale", &scale);
1749         val *= scale;
1750       }
1751       define_variable(defaults_table[i].name, val);
1752       return;
1753     }
1754   lex_error("`%1' is not a predefined variable", nm);
1755 }
1756
1757 void reset_all()
1758 {
1759   // We only have to explicitly reset the pre-defined variables that
1760   // aren't scaled because `scale' is not scaled, and changing the
1761   // value of `scale' will reset all the pre-defined variables that
1762   // are scaled.
1763   for (unsigned int i = 0;
1764        i < sizeof(defaults_table)/sizeof(defaults_table[0]); i++)
1765     if (!defaults_table[i].scaled)
1766       define_variable(defaults_table[i].name, defaults_table[i].val);
1767 }
1768
1769 // called after each parse
1770
1771 void parse_cleanup()
1772 {
1773   while (current_saved_state != 0) {
1774     delete current_table;
1775     current_table = current_saved_state->tbl;
1776     saved_state *tem = current_saved_state;
1777     current_saved_state = current_saved_state->prev;
1778     delete tem;
1779   }
1780   assert(current_table == &top_table);
1781   PTABLE_ITERATOR(place) iter(current_table);
1782   const char *key;
1783   place *pl;
1784   while (iter.next(&key, &pl))
1785     if (pl->obj != 0) {
1786       position pos = pl->obj->origin();
1787       pl->obj = 0;
1788       pl->x = pos.x;
1789       pl->y = pos.y;
1790     }
1791   while (olist.head != 0) {
1792     object *tem = olist.head;
1793     olist.head = olist.head->next;
1794     delete tem;
1795   }
1796   olist.tail = 0;
1797   current_direction = RIGHT_DIRECTION;
1798   current_position.x = 0.0;
1799   current_position.y = 0.0;
1800 }
1801
1802 const char *ordinal_postfix(int n)
1803 {
1804   if (n < 10 || n > 20)
1805     switch (n % 10) {
1806     case 1:
1807       return "st";
1808     case 2:
1809       return "nd";
1810     case 3:
1811       return "rd";
1812     }
1813   return "th";
1814 }
1815
1816 const char *object_type_name(object_type type)
1817 {
1818   switch (type) {
1819   case BOX_OBJECT:
1820     return "box";
1821   case CIRCLE_OBJECT:
1822     return "circle";
1823   case ELLIPSE_OBJECT:
1824     return "ellipse";
1825   case ARC_OBJECT:
1826     return "arc";
1827   case SPLINE_OBJECT:
1828     return "spline";
1829   case LINE_OBJECT:
1830     return "line";
1831   case ARROW_OBJECT:
1832     return "arrow";
1833   case MOVE_OBJECT:
1834     return "move";
1835   case TEXT_OBJECT:
1836     return "\"\"";
1837   case BLOCK_OBJECT:
1838     return "[]";
1839   case OTHER_OBJECT:
1840   case MARK_OBJECT:
1841   default:
1842     break;
1843   }
1844   return "object";
1845 }
1846
1847 static char sprintf_buf[1024];
1848
1849 char *format_number(const char *form, double n)
1850 {
1851   if (form == 0)
1852     form = "%g";
1853   return do_sprintf(form, &n, 1);
1854 }
1855
1856 char *do_sprintf(const char *form, const double *v, int nv)
1857 {
1858   string result;
1859   int i = 0;
1860   string one_format;
1861   while (*form) {
1862     if (*form == '%') {
1863       one_format += *form++;
1864       for (; *form != '\0' && strchr("#-+ 0123456789.", *form) != 0; form++)
1865         one_format += *form;
1866       if (*form == '\0' || strchr("eEfgG%", *form) == 0) {
1867         lex_error("bad sprintf format");
1868         result += one_format;
1869         result += form;
1870         break;
1871       }
1872       if (*form == '%') {
1873         one_format += *form++;
1874         one_format += '\0';
1875         snprintf(sprintf_buf, sizeof(sprintf_buf),
1876                  "%s", one_format.contents());
1877       }
1878       else {
1879         if (i >= nv) {
1880           lex_error("too few arguments to snprintf");
1881           result += one_format;
1882           result += form;
1883           break;
1884         }
1885         one_format += *form++;
1886         one_format += '\0';
1887         snprintf(sprintf_buf, sizeof(sprintf_buf),
1888                  one_format.contents(), v[i++]);
1889       }
1890       one_format.clear();
1891       result += sprintf_buf;
1892     }
1893     else
1894       result += *form++;
1895   }
1896   result += '\0';
1897   return strsave(result.contents());
1898 }