usr.bin/lex/scan.l

   1 /* scan.l - scanner for flex input */
   2
   3 %{
   4 /*-
   5  * Copyright (c) 1990 The Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * This code is derived from software contributed to Berkeley by
   9  * Vern Paxson.
  10  *
  11  * The United States Government has rights in this work pursuant
  12  * to contract no. DE-AC03-76SF00098 between the United States
  13  * Department of Energy and the University of California.
  14  *
  15  * Redistribution and use in source and binary forms are permitted provided
  16  * that: (1) source distributions retain this entire copyright notice and
  17  * comment, and (2) distributions including binaries display the following
  18  * acknowledgement:  ``This product includes software developed by the
  19  * University of California, Berkeley and its contributors'' in the
  20  * documentation or other materials provided with the distribution and in
  21  * all advertising materials mentioning features or use of this software.
  22  * Neither the name of the University nor the names of its contributors may
  23  * be used to endorse or promote products derived from this software without
  24  * specific prior written permission.
  25  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  26  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  27  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  28  */
  29
  30 /* $Header: /home/daffy/u0/vern/flex/RCS/scan.l,v 2.56 95/04/24 12:17:19 vern Exp $ */
  31 /* $FreeBSD: src/usr.bin/lex/scan.l,v 1.5 1999/10/27 07:56:46 obrien Exp $ */
  32 /* $DragonFly: src/usr.bin/lex/scan.l,v 1.3 2008/06/21 19:29:21 swildner Exp $ */
  33
  34 #include "flexdef.h"
  35 #include "parse.h"
  36
  37 #define ACTION_ECHO add_action( yytext )
  38 #define ACTION_IFDEF(def, should_define) \
  39         { \
  40         if ( should_define ) \
  41                 action_define( def, 1 ); \
  42         }
  43
  44 #define MARK_END_OF_PROLOG mark_prolog();
  45
  46 #define YY_DECL \
  47         int flexscan( void )
  48
  49 #define RETURNCHAR \
  50         yylval = (unsigned char) yytext[0]; \
  51         return CHAR;
  52
  53 #define RETURNNAME \
  54         strcpy( nmstr, yytext ); \
  55         return NAME;
  56
  57 #define PUT_BACK_STRING(str, start) \
  58         for ( i = strlen( str ) - 1; i >= start; --i ) \
  59                 unput((str)[i])
  60
  61 #define CHECK_REJECT(str) \
  62         if ( all_upper( str ) ) \
  63                 reject = true;
  64
  65 #define CHECK_YYMORE(str) \
  66         if ( all_lower( str ) ) \
  67                 yymore_used = true;
  68 %}
  69
  70 %option caseless nodefault outfile="scan.c" stack noyy_top_state
  71 %option nostdinit
  72
  73 %x SECT2 SECT2PROLOG SECT3 CODEBLOCK PICKUPDEF SC CARETISBOL NUM QUOTE
  74 %x FIRSTCCL CCL ACTION RECOVER COMMENT ACTION_STRING PERCENT_BRACE_ACTION
  75 %x OPTION LINEDIR
  76
  77 WS              [[:blank:]]+
  78 OPTWS           [[:blank:]]*
  79 NOT_WS          [^[:blank:]\n]
  80
  81 NL              \r?\n
  82
  83 NAME            ([[:alpha:]_][[:alnum:]_-]*)
  84 NOT_NAME        [^[:alpha:]_*\n]+
  85
  86 SCNAME          {NAME}
  87
  88 ESCSEQ          (\\([^\n]|[0-7]{1,3}|x[[:xdigit:]]{1,2}))
  89
  90 FIRST_CCL_CHAR  ([^\\\n]|{ESCSEQ})
  91 CCL_CHAR        ([^\\\n\]]|{ESCSEQ})
  92 CCL_EXPR        ("[:"[[:alpha:]]+":]")
  93
  94 LEXOPT          [aceknopr]
  95
  96 %%
  97         static int bracelevel, didadef, indented_code;
  98         static int doing_rule_action = false;
  99         static int option_sense;
 100
 101         int doing_codeblock = false;
 102         int i;
 103         Char nmdef[MAXLINE], myesc();
 104
 105
 106 <INITIAL>{
 107         ^{WS}           indented_code = true; BEGIN(CODEBLOCK);
 108         ^"/*"           ACTION_ECHO; yy_push_state( COMMENT );
 109         ^#{OPTWS}line{WS}       yy_push_state( LINEDIR );
 110         ^"%s"{NAME}?    return SCDECL;
 111         ^"%x"{NAME}?    return XSCDECL;
 112         ^"%{".*{NL}     {
 113                         ++linenum;
 114                         line_directive_out( (FILE *) 0, 1 );
 115                         indented_code = false;
 116                         BEGIN(CODEBLOCK);
 117                         }
 118
 119         {WS}            /* discard */
 120
 121         ^"%%".*         {
 122                         sectnum = 2;
 123                         bracelevel = 0;
 124                         mark_defs1();
 125                         line_directive_out( (FILE *) 0, 1 );
 126                         BEGIN(SECT2PROLOG);
 127                         return SECTEND;
 128                         }
 129
 130         ^"%pointer".*{NL}       yytext_is_array = false; ++linenum;
 131         ^"%array".*{NL}         yytext_is_array = true; ++linenum;
 132
 133         ^"%option"      BEGIN(OPTION); return OPTION_OP;
 134
 135         ^"%"{LEXOPT}{OPTWS}[[:digit:]]*{OPTWS}{NL}      ++linenum; /* ignore */
 136         ^"%"{LEXOPT}{WS}.*{NL}  ++linenum;      /* ignore */
 137
 138         ^"%"[^sxaceknopr{}].*   synerr( _( "unrecognized '%' directive" ) );
 139
 140         ^{NAME}         {
 141                         strcpy( nmstr, yytext );
 142                         didadef = false;
 143                         BEGIN(PICKUPDEF);
 144                         }
 145
 146         {SCNAME}        RETURNNAME;
 147         ^{OPTWS}{NL}    ++linenum; /* allows blank lines in section 1 */
 148         {OPTWS}{NL}     ACTION_ECHO; ++linenum; /* maybe end of comment line */
 149 }
 150
 151
 152 <COMMENT>{
 153         "*/"            ACTION_ECHO; yy_pop_state();
 154         "*"             ACTION_ECHO;
 155         [^*\n]+         ACTION_ECHO;
 156         [^*\n]*{NL}     ++linenum; ACTION_ECHO;
 157 }
 158
 159 <LINEDIR>{
 160         \n              yy_pop_state();
 161         [[:digit:]]+    linenum = myctoi( yytext );
 162
 163         \"[^"\n]*\"     {
 164                         flex_free( (void *) infilename );
 165                         infilename = copy_string( yytext + 1 );
 166                         infilename[strlen( infilename ) - 1] = '\0';
 167                         }
 168         .               /* ignore spurious characters */
 169 }
 170
 171 <CODEBLOCK>{
 172         ^"%}".*{NL}     ++linenum; BEGIN(INITIAL);
 173
 174         {NAME}|{NOT_NAME}|.     ACTION_ECHO;
 175
 176         {NL}            {
 177                         ++linenum;
 178                         ACTION_ECHO;
 179                         if ( indented_code )
 180                                 BEGIN(INITIAL);
 181                         }
 182 }
 183
 184
 185 <PICKUPDEF>{
 186         {WS}            /* separates name and definition */
 187
 188         {NOT_WS}.*      {
 189                         strcpy( (char *) nmdef, yytext );
 190
 191                         /* Skip trailing whitespace. */
 192                         for ( i = strlen( (char *) nmdef ) - 1;
 193                               i >= 0 && (nmdef[i] == ' ' || nmdef[i] == '\t');
 194                               --i )
 195                                 ;
 196
 197                         nmdef[i + 1] = '\0';
 198
 199                         ndinstal( nmstr, nmdef );
 200                         didadef = true;
 201                         }
 202
 203         {NL}            {
 204                         if ( ! didadef )
 205                                 synerr( _( "incomplete name definition" ) );
 206                         BEGIN(INITIAL);
 207                         ++linenum;
 208                         }
 209 }
 210
 211
 212 <OPTION>{
 213         {NL}            ++linenum; BEGIN(INITIAL);
 214         {WS}            option_sense = true;
 215
 216         "="             return '=';
 217
 218         no              option_sense = ! option_sense;
 219
 220         7bit            csize = option_sense ? 128 : 256;
 221         8bit            csize = option_sense ? 256 : 128;
 222
 223         align           long_align = option_sense;
 224         always-interactive      {
 225                         action_define( "YY_ALWAYS_INTERACTIVE", option_sense );
 226                         }
 227         array           yytext_is_array = option_sense;
 228         backup          backing_up_report = option_sense;
 229         batch           interactive = ! option_sense;
 230         "c++"           C_plus_plus = option_sense;
 231         caseful|case-sensitive          caseins = ! option_sense;
 232         caseless|case-insensitive       caseins = option_sense;
 233         debug           ddebug = option_sense;
 234         default         spprdflt = ! option_sense;
 235         ecs             useecs = option_sense;
 236         fast            {
 237                         useecs = usemecs = false;
 238                         use_read = fullspd = true;
 239                         }
 240         full            {
 241                         useecs = usemecs = false;
 242                         use_read = fulltbl = true;
 243                         }
 244         input           ACTION_IFDEF("YY_NO_INPUT", ! option_sense);
 245         interactive     interactive = option_sense;
 246         lex-compat      lex_compat = option_sense;
 247         main            {
 248                         action_define( "YY_MAIN", option_sense );
 249                         do_yywrap = ! option_sense;
 250                         }
 251         meta-ecs        usemecs = option_sense;
 252         never-interactive       {
 253                         action_define( "YY_NEVER_INTERACTIVE", option_sense );
 254                         }
 255         perf-report     performance_report += option_sense ? 1 : -1;
 256         pointer         yytext_is_array = ! option_sense;
 257         read            use_read = option_sense;
 258         reject          reject_really_used = option_sense;
 259         stack           action_define( "YY_STACK_USED", option_sense );
 260         stdinit         do_stdinit = option_sense;
 261         stdout          use_stdout = option_sense;
 262         unput           ACTION_IFDEF("YY_NO_UNPUT", ! option_sense);
 263         verbose         printstats = option_sense;
 264         warn            nowarn = ! option_sense;
 265         yylineno        do_yylineno = option_sense;
 266         yymore          yymore_really_used = option_sense;
 267         yywrap          do_yywrap = option_sense;
 268
 269         yy_push_state   ACTION_IFDEF("YY_NO_PUSH_STATE", ! option_sense);
 270         yy_pop_state    ACTION_IFDEF("YY_NO_POP_STATE", ! option_sense);
 271         yy_top_state    ACTION_IFDEF("YY_NO_TOP_STATE", ! option_sense);
 272
 273         yy_scan_buffer  ACTION_IFDEF("YY_NO_SCAN_BUFFER", ! option_sense);
 274         yy_scan_bytes   ACTION_IFDEF("YY_NO_SCAN_BYTES", ! option_sense);
 275         yy_scan_string  ACTION_IFDEF("YY_NO_SCAN_STRING", ! option_sense);
 276
 277         outfile         return OPT_OUTFILE;
 278         prefix          return OPT_PREFIX;
 279         yyclass         return OPT_YYCLASS;
 280
 281         \"[^"\n]*\"     {
 282                         strcpy( nmstr, yytext + 1 );
 283                         nmstr[strlen( nmstr ) - 1] = '\0';
 284                         return NAME;
 285                         }
 286
 287         (([a-mo-z]|n[a-np-z])[[:alpha:]\-+]*)|. {
 288                         format_synerr( _( "unrecognized %%option: %s" ),
 289                                 yytext );
 290                         BEGIN(RECOVER);
 291                         }
 292 }
 293
 294 <RECOVER>.*{NL}         ++linenum; BEGIN(INITIAL);
 295
 296
 297 <SECT2PROLOG>{
 298         ^"%{".* ++bracelevel; yyless( 2 );      /* eat only %{ */
 299         ^"%}".* --bracelevel; yyless( 2 );      /* eat only %} */
 300
 301         ^{WS}.* ACTION_ECHO;    /* indented code in prolog */
 302
 303         ^{NOT_WS}.*     {       /* non-indented code */
 304                         if ( bracelevel <= 0 )
 305                                 { /* not in %{ ... %} */
 306                                 yyless( 0 );    /* put it all back */
 307                                 yy_set_bol( 1 );
 308                                 mark_prolog();
 309                                 BEGIN(SECT2);
 310                                 }
 311                         else
 312                                 ACTION_ECHO;
 313                         }
 314
 315         .*              ACTION_ECHO;
 316         {NL}    ++linenum; ACTION_ECHO;
 317
 318         <<EOF>>         {
 319                         mark_prolog();
 320                         sectnum = 0;
 321                         yyterminate(); /* to stop the parser */
 322                         }
 323 }
 324
 325 <SECT2>{
 326         ^{OPTWS}{NL}    ++linenum; /* allow blank lines in section 2 */
 327
 328         ^{OPTWS}"%{"    {
 329                         indented_code = false;
 330                         doing_codeblock = true;
 331                         bracelevel = 1;
 332                         BEGIN(PERCENT_BRACE_ACTION);
 333                         }
 334
 335         ^{OPTWS}"<"     BEGIN(SC); return '<';
 336         ^{OPTWS}"^"     return '^';
 337         \"              BEGIN(QUOTE); return '"';
 338         "{"/[[:digit:]] BEGIN(NUM); return '{';
 339         "$"/([[:blank:]]|{NL})  return '$';
 340
 341         {WS}"%{"                {
 342                         bracelevel = 1;
 343                         BEGIN(PERCENT_BRACE_ACTION);
 344
 345                         if ( in_rule )
 346                                 {
 347                                 doing_rule_action = true;
 348                                 in_rule = false;
 349                                 return '\n';
 350                                 }
 351                         }
 352         {WS}"|".*{NL}   continued_action = true; ++linenum; return '\n';
 353
 354         ^{WS}"/*"       {
 355                         yyless( yyleng - 2 );   /* put back '/', '*' */
 356                         bracelevel = 0;
 357                         continued_action = false;
 358                         BEGIN(ACTION);
 359                         }
 360
 361         ^{WS}           /* allow indented rules */
 362
 363         {WS}            {
 364                         /* This rule is separate from the one below because
 365                          * otherwise we get variable trailing context, so
 366                          * we can't build the scanner using -{f,F}.
 367                          */
 368                         bracelevel = 0;
 369                         continued_action = false;
 370                         BEGIN(ACTION);
 371
 372                         if ( in_rule )
 373                                 {
 374                                 doing_rule_action = true;
 375                                 in_rule = false;
 376                                 return '\n';
 377                                 }
 378                         }
 379
 380         {OPTWS}{NL}     {
 381                         bracelevel = 0;
 382                         continued_action = false;
 383                         BEGIN(ACTION);
 384                         unput( '\n' );  /* so <ACTION> sees it */
 385
 386                         if ( in_rule )
 387                                 {
 388                                 doing_rule_action = true;
 389                                 in_rule = false;
 390                                 return '\n';
 391                                 }
 392                         }
 393
 394         ^{OPTWS}"<<EOF>>"       |
 395         "<<EOF>>"       return EOF_OP;
 396
 397         ^"%%".*         {
 398                         sectnum = 3;
 399                         BEGIN(SECT3);
 400                         yyterminate(); /* to stop the parser */
 401                         }
 402
 403         "["({FIRST_CCL_CHAR}|{CCL_EXPR})({CCL_CHAR}|{CCL_EXPR})*        {
 404                         int cclval;
 405
 406                         strcpy( nmstr, yytext );
 407
 408                         /* Check to see if we've already encountered this
 409                          * ccl.
 410                          */
 411                         if ( (cclval = ccllookup( (Char *) nmstr )) != 0 )
 412                                 {
 413                                 if ( input() != ']' )
 414                                         synerr( _( "bad character class" ) );
 415
 416                                 yylval = cclval;
 417                                 ++cclreuse;
 418                                 return PREVCCL;
 419                                 }
 420                         else
 421                                 {
 422                                 /* We fudge a bit.  We know that this ccl will
 423                                  * soon be numbered as lastccl + 1 by cclinit.
 424                                  */
 425                                 cclinstal( (Char *) nmstr, lastccl + 1 );
 426
 427                                 /* Push back everything but the leading bracket
 428                                  * so the ccl can be rescanned.
 429                                  */
 430                                 yyless( 1 );
 431
 432                                 BEGIN(FIRSTCCL);
 433                                 return '[';
 434                                 }
 435                         }
 436
 437         "{"{NAME}"}"    {
 438                         register Char *nmdefptr;
 439                         Char *ndlookup();
 440
 441                         strcpy( nmstr, yytext + 1 );
 442                         nmstr[yyleng - 2] = '\0';  /* chop trailing brace */
 443
 444                         if ( (nmdefptr = ndlookup( nmstr )) == 0 )
 445                                 format_synerr(
 446                                         _( "undefined definition {%s}" ),
 447                                                 nmstr );
 448
 449                         else
 450                                 { /* push back name surrounded by ()'s */
 451                                 int len = strlen( (char *) nmdefptr );
 452
 453                                 if ( lex_compat || nmdefptr[0] == '^' ||
 454                                      (len > 0 && nmdefptr[len - 1] == '$') )
 455                                         { /* don't use ()'s after all */
 456                                         PUT_BACK_STRING((char *) nmdefptr, 0);
 457
 458                                         if ( nmdefptr[0] == '^' )
 459                                                 BEGIN(CARETISBOL);
 460                                         }
 461
 462                                 else
 463                                         {
 464                                         unput(')');
 465                                         PUT_BACK_STRING((char *) nmdefptr, 0);
 466                                         unput('(');
 467                                         }
 468                                 }
 469                         }
 470
 471         [/|*+?.(){}]    return (unsigned char) yytext[0];
 472         .               RETURNCHAR;
 473 }
 474
 475
 476 <SC>{
 477         [,*]            return (unsigned char) yytext[0];
 478         ">"             BEGIN(SECT2); return '>';
 479         ">"/^           BEGIN(CARETISBOL); return '>';
 480         {SCNAME}        RETURNNAME;
 481         .               {
 482                         format_synerr( _( "bad <start condition>: %s" ),
 483                                 yytext );
 484                         }
 485 }
 486
 487 <CARETISBOL>"^"         BEGIN(SECT2); return '^';
 488
 489
 490 <QUOTE>{
 491         [^"\n]          RETURNCHAR;
 492         \"              BEGIN(SECT2); return '"';
 493
 494         {NL}            {
 495                         synerr( _( "missing quote" ) );
 496                         BEGIN(SECT2);
 497                         ++linenum;
 498                         return '"';
 499                         }
 500 }
 501
 502
 503 <FIRSTCCL>{
 504         "^"/[^-\]\n]    BEGIN(CCL); return '^';
 505         "^"/("-"|"]")   return '^';
 506         .               BEGIN(CCL); RETURNCHAR;
 507 }
 508
 509 <CCL>{
 510         -/[^\]\n]       return '-';
 511         [^\]\n]         RETURNCHAR;
 512         "]"             BEGIN(SECT2); return ']';
 513         .|{NL}          {
 514                         synerr( _( "bad character class" ) );
 515                         BEGIN(SECT2);
 516                         return ']';
 517                         }
 518 }
 519
 520 <FIRSTCCL,CCL>{
 521         "[:alnum:]"     BEGIN(CCL); return CCE_ALNUM;
 522         "[:alpha:]"     BEGIN(CCL); return CCE_ALPHA;
 523         "[:blank:]"     BEGIN(CCL); return CCE_BLANK;
 524         "[:cntrl:]"     BEGIN(CCL); return CCE_CNTRL;
 525         "[:digit:]"     BEGIN(CCL); return CCE_DIGIT;
 526         "[:graph:]"     BEGIN(CCL); return CCE_GRAPH;
 527         "[:lower:]"     BEGIN(CCL); return CCE_LOWER;
 528         "[:print:]"     BEGIN(CCL); return CCE_PRINT;
 529         "[:punct:]"     BEGIN(CCL); return CCE_PUNCT;
 530         "[:space:]"     BEGIN(CCL); return CCE_SPACE;
 531         "[:upper:]"     BEGIN(CCL); return CCE_UPPER;
 532         "[:xdigit:]"    BEGIN(CCL); return CCE_XDIGIT;
 533         {CCL_EXPR}      {
 534                         format_synerr(
 535                                 _( "bad character class expression: %s" ),
 536                                         yytext );
 537                         BEGIN(CCL); return CCE_ALNUM;
 538                         }
 539 }
 540
 541 <NUM>{
 542         [[:digit:]]+    {
 543                         yylval = myctoi( yytext );
 544                         return NUMBER;
 545                         }
 546
 547         ","             return ',';
 548         "}"             BEGIN(SECT2); return '}';
 549
 550         .               {
 551                         synerr( _( "bad character inside {}'s" ) );
 552                         BEGIN(SECT2);
 553                         return '}';
 554                         }
 555
 556         {NL}            {
 557                         synerr( _( "missing }" ) );
 558                         BEGIN(SECT2);
 559                         ++linenum;
 560                         return '}';
 561                         }
 562 }
 563
 564
 565 <PERCENT_BRACE_ACTION>{
 566         {OPTWS}"%}".*           bracelevel = 0;
 567
 568         <ACTION>"/*"            ACTION_ECHO; yy_push_state( COMMENT );
 569
 570         <CODEBLOCK,ACTION>{
 571                 "reject"        {
 572                         ACTION_ECHO;
 573                         CHECK_REJECT(yytext);
 574                         }
 575                 "yymore"        {
 576                         ACTION_ECHO;
 577                         CHECK_YYMORE(yytext);
 578                         }
 579         }
 580
 581         {NAME}|{NOT_NAME}|.     ACTION_ECHO;
 582         {NL}            {
 583                         ++linenum;
 584                         ACTION_ECHO;
 585                         if ( bracelevel == 0 ||
 586                              (doing_codeblock && indented_code) )
 587                                 {
 588                                 if ( doing_rule_action )
 589                                         add_action( "\tYY_BREAK\n" );
 590
 591                                 doing_rule_action = doing_codeblock = false;
 592                                 BEGIN(SECT2);
 593                                 }
 594                         }
 595 }
 596
 597
 598         /* Reject and YYmore() are checked for above, in PERCENT_BRACE_ACTION */
 599 <ACTION>{
 600         "{"             ACTION_ECHO; ++bracelevel;
 601         "}"             ACTION_ECHO; --bracelevel;
 602         [^[:alpha:]_{}"'/\n]+   ACTION_ECHO;
 603         {NAME}          ACTION_ECHO;
 604         "'"([^'\\\n]|\\.)*"'"   ACTION_ECHO; /* character constant */
 605         \"              ACTION_ECHO; BEGIN(ACTION_STRING);
 606         {NL}            {
 607                         ++linenum;
 608                         ACTION_ECHO;
 609                         if ( bracelevel == 0 )
 610                                 {
 611                                 if ( doing_rule_action )
 612                                         add_action( "\tYY_BREAK\n" );
 613
 614                                 doing_rule_action = false;
 615                                 BEGIN(SECT2);
 616                                 }
 617                         }
 618         .               ACTION_ECHO;
 619 }
 620
 621 <ACTION_STRING>{
 622         [^"\\\n]+       ACTION_ECHO;
 623         \\.             ACTION_ECHO;
 624         {NL}            ++linenum; ACTION_ECHO;
 625         \"              ACTION_ECHO; BEGIN(ACTION);
 626         .               ACTION_ECHO;
 627 }
 628
 629 <COMMENT,ACTION,ACTION_STRING><<EOF>>   {
 630                         synerr( _( "EOF encountered inside an action" ) );
 631                         yyterminate();
 632                         }
 633
 634
 635 <SECT2,QUOTE,FIRSTCCL,CCL>{ESCSEQ}      {
 636                         yylval = myesc( (Char *) yytext );
 637
 638                         if ( YY_START == FIRSTCCL )
 639                                 BEGIN(CCL);
 640
 641                         return CHAR;
 642                         }
 643
 644
 645 <SECT3>{
 646         .*(\n?)         ECHO;
 647         <<EOF>>         sectnum = 0; yyterminate();
 648 }
 649
 650 <*>.|\n                 format_synerr( _( "bad character: %s" ), yytext );
 651
 652 %%
 653
 654
 655 int yywrap( void )
 656         {
 657         if ( --num_input_files > 0 )
 658                 {
 659                 set_input_file( *++input_files );
 660                 return 0;
 661                 }
 662
 663         else
 664                 return 1;
 665         }
 666
 667
 668 /* set_input_file - open the given file (if NULL, stdin) for scanning */
 669
 670 void set_input_file( char *file )
 671         {
 672         if ( file && strcmp( file, "-" ) )
 673                 {
 674                 infilename = copy_string( file );
 675                 yyin = fopen( infilename, "r" );
 676
 677                 if ( yyin == NULL )
 678                         lerrsf( _( "can't open %s" ), file );
 679                 }
 680
 681         else
 682                 {
 683                 yyin = stdin;
 684                 infilename = copy_string( "<stdin>" );
 685                 }
 686
 687         linenum = 1;
 688         }
 689
 690
 691 /* Wrapper routines for accessing the scanner's malloc routines. */
 692
 693 void *flex_alloc( size_t size )
 694         {
 695         return (void *) malloc( size );
 696         }
 697
 698 void *flex_realloc( void *ptr, size_t size )
 699         {
 700         return (void *) realloc( ptr, size );
 701         }
 702
 703 void flex_free( void *ptr )
 704         {
 705         if ( ptr )
 706                 free( ptr );
 707         }