ragel/main.cpp

   1 /*
   2  *  Copyright 2001-2007 Adrian Thurston <thurston@cs.queensu.ca>
   3  */
   4
   5 /*  This file is part of Ragel.
   6  *
   7  *  Ragel is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  Ragel is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with Ragel; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <stdio.h>
  25 #include <iostream>
  26 #include <fstream>
  27 #include <unistd.h>
  28 #include <sstream>
  29 #include <unistd.h>
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32 #include <fcntl.h>
  33 #include <errno.h>
  34
  35 #ifndef _WIN32
  36 #include <sys/wait.h>
  37 #else
  38 #include <windows.h>
  39 #include <psapi.h>
  40 #include <time.h>
  41 #include <io.h>
  42 #include <process.h>
  43
  44 #if _MSC_VER
  45 #define S_IRUSR _S_IREAD
  46 #define S_IWUSR _S_IWRITE
  47 #endif
  48 #endif
  49
  50 /* Parsing. */
  51 #include "ragel.h"
  52 #include "rlscan.h"
  53
  54 /* Parameters and output. */
  55 #include "pcheck.h"
  56 #include "vector.h"
  57 #include "version.h"
  58 #include "common.h"
  59
  60 using std::istream;
  61 using std::ostream;
  62 using std::ifstream;
  63 using std::ofstream;
  64 using std::cin;
  65 using std::cout;
  66 using std::cerr;
  67 using std::endl;
  68 using std::ios;
  69 using std::streamsize;
  70
  71 /* Controls minimization. */
  72 MinimizeLevel minimizeLevel = MinimizePartition2;
  73 MinimizeOpt minimizeOpt = MinimizeMostOps;
  74
  75 /* Graphviz dot file generation. */
  76 char *machineSpec = 0, *machineName = 0;
  77 bool machineSpecFound = false;
  78 bool wantDupsRemoved = true;
  79
  80 bool printStatistics = false;
  81 bool frontendOnly = false;
  82 bool generateDot = false;
  83
  84 ArgsVector frontendArgs;
  85 ArgsVector backendArgs;
  86 ArgsVector includePaths;
  87
  88 /* Print a summary of the options. */
  89 void usage()
  90 {
  91         cout <<
  92 "usage: ragel [options] file\n"
  93 "general:\n"
  94 "   -h, -H, -?, --help   Print this usage and exit\n"
  95 "   -v, --version        Print version information and exit\n"
  96 "   -o <file>            Write output to <file>\n"
  97 "   -s                   Print some statistics on stderr\n"
  98 "   -d                   Do not remove duplicates from action lists\n"
  99 "   -I <dir>             Add <dir> to the list of directories to search\n"
 100 "                        for included an imported files\n"
 101 "error reporting format:\n"
 102 "   --error-format=gnu   file:line:column: message (default)\n"
 103 "   --error-format=msvc  file(line,column): message\n"
 104 "fsm minimization:\n"
 105 "   -n                   Do not perform minimization\n"
 106 "   -m                   Minimize at the end of the compilation\n"
 107 "   -l                   Minimize after most operations (default)\n"
 108 "   -e                   Minimize after every operation\n"
 109 "visualization:\n"
 110 "   -x                   Run the frontend only: emit XML intermediate format\n"
 111 "   -V                   Generate a dot file for Graphviz\n"
 112 "   -p                   Display printable characters on labels\n"
 113 "   -S <spec>            FSM specification to output (for rlgen-dot)\n"
 114 "   -M <machine>         Machine definition/instantiation to output (for rlgen-dot)\n"
 115 "host language:\n"
 116 "   -C                   The host language is C, C++, Obj-C or Obj-C++ (default)\n"
 117 "   -D                   The host language is D\n"
 118 "   -J                   The host language is Java\n"
 119 "   -R                   The host language is Ruby\n"
 120 "   -A                   The host language is C#\n"
 121 "line direcives: (C/D/C# only)\n"
 122 "   -L                   Inhibit writing of #line directives\n"
 123 "code style: (C/Ruby/C# only)\n"
 124 "   -T0                  Table driven FSM (default)\n"
 125 "   -T1                  Faster table driven FSM\n"
 126 "   -F0                  Flat table driven FSM\n"
 127 "   -F1                  Faster flat table-driven FSM\n"
 128 "code style: (C/C# only)\n"
 129 "   -G0                  Goto-driven FSM\n"
 130 "   -G1                  Faster goto-driven FSM\n"
 131 "code style: (C only)\n"
 132 "   -G2                  Really fast goto-driven FSM\n"
 133 "   -P<N>                N-Way Split really fast goto-driven FSM\n"
 134         ;
 135
 136         exit(0);
 137 }
 138
 139 /* Print version information and exit. */
 140 void version()
 141 {
 142         cout << "Ragel State Machine Compiler version " VERSION << " " PUBDATE << endl <<
 143                         "Copyright (c) 2001-2007 by Adrian Thurston" << endl;
 144         exit(0);
 145 }
 146
 147 /* Error reporting format. */
 148 ErrorFormat errorFormat = ErrorFormatGNU;
 149
 150 InputLoc makeInputLoc( const char *fileName, int line, int col)
 151 {
 152         InputLoc loc = { fileName, line, col };
 153         return loc;
 154 }
 155
 156 ostream &operator<<( ostream &out, const InputLoc &loc )
 157 {
 158         assert( loc.fileName != 0 );
 159         switch ( errorFormat ) {
 160         case ErrorFormatMSVC:
 161                 out << loc.fileName << "(" << loc.line;
 162                 if ( loc.col )
 163                         out << "," << loc.col;
 164                 out << ")";
 165                 break;
 166
 167         default:
 168                 out << loc.fileName << ":" << loc.line;
 169                 if ( loc.col )
 170                         out << ":" << loc.col;
 171                 break;
 172         }
 173         return out;
 174 }
 175
 176 /* Total error count. */
 177 int gblErrorCount = 0;
 178
 179 /* Print the opening to a warning in the input, then return the error ostream. */
 180 ostream &warning( const InputLoc &loc )
 181 {
 182         cerr << loc << ": warning: ";
 183         return cerr;
 184 }
 185
 186 /* Print the opening to a program error, then return the error stream. */
 187 ostream &error()
 188 {
 189         gblErrorCount += 1;
 190         cerr << PROGNAME ": ";
 191         return cerr;
 192 }
 193
 194 ostream &error( const InputLoc &loc )
 195 {
 196         gblErrorCount += 1;
 197         cerr << loc << ": ";
 198         return cerr;
 199 }
 200
 201 void escapeLineDirectivePath( std::ostream &out, char *path )
 202 {
 203         for ( char *pc = path; *pc != 0; pc++ ) {
 204                 if ( *pc == '\\' )
 205                         out << "\\\\";
 206                 else
 207                         out << *pc;
 208         }
 209 }
 210
 211 void processArgs( int argc, char **argv, char *&inputFileName, char *&outputFileName )
 212 {
 213         ParamCheck pc("xo:dnmleabjkS:M:I:CDJRAvHh?-:sT:F:G:P:LpV", argc, argv);
 214
 215         while ( pc.check() ) {
 216                 switch ( pc.state ) {
 217                 case ParamCheck::match:
 218                         switch ( pc.parameter ) {
 219                         case 'V':
 220                                 generateDot = true;
 221                                 break;
 222
 223                         case 'x':
 224                                 frontendOnly = true;
 225                                 break;
 226
 227                         /* Output. */
 228                         case 'o':
 229                                 if ( *pc.paramArg == 0 )
 230                                         error() << "a zero length output file name was given" << endl;
 231                                 else if ( outputFileName != 0 )
 232                                         error() << "more than one output file name was given" << endl;
 233                                 else {
 234                                         /* Ok, remember the output file name. */
 235                                         outputFileName = pc.paramArg;
 236                                 }
 237                                 break;
 238
 239                         /* Minimization, mostly hidden options. */
 240                         case 'd':
 241                                 wantDupsRemoved = false;
 242                                 frontendArgs.append( "-d" );
 243                                 break;
 244
 245                         /* Minimization, mostly hidden options. */
 246                         case 'n':
 247                                 minimizeOpt = MinimizeNone;
 248                                 frontendArgs.append( "-n" );
 249                                 break;
 250                         case 'm':
 251                                 minimizeOpt = MinimizeEnd;
 252                                 frontendArgs.append( "-m" );
 253                                 break;
 254                         case 'l':
 255                                 minimizeOpt = MinimizeMostOps;
 256                                 frontendArgs.append( "-l" );
 257                                 break;
 258                         case 'e':
 259                                 minimizeOpt = MinimizeEveryOp;
 260                                 frontendArgs.append( "-e" );
 261                                 break;
 262                         case 'a':
 263                                 minimizeLevel = MinimizeApprox;
 264                                 frontendArgs.append( "-a" );
 265                                 break;
 266                         case 'b':
 267                                 minimizeLevel = MinimizeStable;
 268                                 frontendArgs.append( "-b" );
 269                                 break;
 270                         case 'j':
 271                                 minimizeLevel = MinimizePartition1;
 272                                 frontendArgs.append( "-j" );
 273                                 break;
 274                         case 'k':
 275                                 minimizeLevel = MinimizePartition2;
 276                                 frontendArgs.append( "-k" );
 277                                 break;
 278
 279                         /* Machine spec. */
 280                         case 'S':
 281                                 if ( *pc.paramArg == 0 )
 282                                         error() << "please specify an argument to -S" << endl;
 283                                 else if ( machineSpec != 0 )
 284                                         error() << "more than one -S argument was given" << endl;
 285                                 else {
 286                                         /* Ok, remember the path to the machine to generate. */
 287                                         machineSpec = pc.paramArg;
 288                                         frontendArgs.append( "-S" );
 289                                         frontendArgs.append( pc.paramArg );
 290                                 }
 291                                 break;
 292
 293                         /* Machine path. */
 294                         case 'M':
 295                                 if ( *pc.paramArg == 0 )
 296                                         error() << "please specify an argument to -M" << endl;
 297                                 else if ( machineName != 0 )
 298                                         error() << "more than one -M argument was given" << endl;
 299                                 else {
 300                                         /* Ok, remember the machine name to generate. */
 301                                         machineName = pc.paramArg;
 302                                         frontendArgs.append( "-M" );
 303                                         frontendArgs.append( pc.paramArg );
 304                                 }
 305                                 break;
 306
 307                         case 'I':
 308                                 if ( *pc.paramArg == 0 )
 309                                         error() << "please specify an argument to -I" << endl;
 310                                 else {
 311                                         includePaths.append( pc.paramArg );
 312                                         frontendArgs.append( "-I" );
 313                                         frontendArgs.append( pc.paramArg );
 314                                 }
 315                                 break;
 316
 317                         /* Host language types. */
 318                         case 'C':
 319                                 hostLang = &hostLangC;
 320                                 frontendArgs.append( "-C" );
 321                                 break;
 322                         case 'D':
 323                                 hostLang = &hostLangD;
 324                                 frontendArgs.append( "-D" );
 325                                 break;
 326                         case 'J':
 327                                 hostLang = &hostLangJava;
 328                                 frontendArgs.append( "-J" );
 329                                 break;
 330                         case 'R':
 331                                 hostLang = &hostLangRuby;
 332                                 frontendArgs.append( "-R" );
 333                                 break;
 334                         case 'A':
 335                                 hostLang = &hostLangCSharp;
 336                                 frontendArgs.append( "-A" );
 337                                 break;
 338
 339                         /* Version and help. */
 340                         case 'v':
 341                                 version();
 342                                 break;
 343                         case 'H': case 'h': case '?':
 344                                 usage();
 345                                 break;
 346                         case 's':
 347                                 printStatistics = true;
 348                                 frontendArgs.append( "-s" );
 349                                 break;
 350                         case '-': {
 351                                 char *eq = strchr( pc.paramArg, '=' );
 352
 353                                 if ( eq != 0 )
 354                                         *eq++ = 0;
 355
 356                                 if ( strcmp( pc.paramArg, "help" ) == 0 )
 357                                         usage();
 358                                 else if ( strcmp( pc.paramArg, "version" ) == 0 )
 359                                         version();
 360                                 else if ( strcmp( pc.paramArg, "error-format" ) == 0 ) {
 361                                         if ( eq == 0 )
 362                                                 error() << "expecting '=value' for error-format" << endl;
 363                                         else if ( strcmp( eq, "gnu" ) == 0 ) {
 364                                                 errorFormat = ErrorFormatGNU;
 365                                                 frontendArgs.append( "--error-format=gnu" );
 366                                         }
 367                                         else if ( strcmp( eq, "msvc" ) == 0 ) {
 368                                                 errorFormat = ErrorFormatMSVC;
 369                                                 frontendArgs.append( "--error-format=msvc" );
 370                                         }
 371                                         else {
 372                                                 error() << "invalid value for error-format" << endl;
 373                                         }
 374                                 }
 375                                 else if ( strcmp( pc.paramArg, "rbx" ) == 0 )
 376                                         backendArgs.append( "--rbx" );
 377                                 else {
 378                                         error() << "--" << pc.paramArg <<
 379                                                         " is an invalid argument" << endl;
 380                                 }
 381                                 break;
 382                         }
 383
 384                         /* Passthrough args. */
 385                         case 'T':
 386                                 backendArgs.append( "-T" );
 387                                 backendArgs.append( pc.paramArg );
 388                                 break;
 389                         case 'F':
 390                                 backendArgs.append( "-F" );
 391                                 backendArgs.append( pc.paramArg );
 392                                 break;
 393                         case 'G':
 394                                 backendArgs.append( "-G" );
 395                                 backendArgs.append( pc.paramArg );
 396                                 break;
 397                         case 'P':
 398                                 backendArgs.append( "-P" );
 399                                 backendArgs.append( pc.paramArg );
 400                                 break;
 401                         case 'p':
 402                                 backendArgs.append( "-p" );
 403                                 break;
 404                         case 'L':
 405                                 backendArgs.append( "-L" );
 406                                 break;
 407                         }
 408                         break;
 409
 410                 case ParamCheck::invalid:
 411                         error() << "-" << pc.parameter << " is an invalid argument" << endl;
 412                         break;
 413
 414                 case ParamCheck::noparam:
 415                         /* It is interpreted as an input file. */
 416                         if ( *pc.curArg == 0 )
 417                                 error() << "a zero length input file name was given" << endl;
 418                         else if ( inputFileName != 0 )
 419                                 error() << "more than one input file name was given" << endl;
 420                         else {
 421                                 /* OK, Remember the filename. */
 422                                 inputFileName = pc.curArg;
 423                         }
 424                         break;
 425                 }
 426         }
 427 }
 428
 429 int frontend( char *inputFileName, char *outputFileName )
 430 {
 431         /* Open the input file for reading. */
 432         assert( inputFileName != 0 );
 433         ifstream *inFile = new ifstream( inputFileName );
 434         istream *inStream = inFile;
 435         if ( ! inFile->is_open() )
 436                 error() << "could not open " << inputFileName << " for reading" << endp;
 437
 438         /* Used for just a few things. */
 439         std::ostringstream hostData;
 440
 441         if ( machineSpec == 0 && machineName == 0 )
 442                 hostData << "<host line=\"1\" col=\"1\">";
 443
 444         Scanner scanner( inputFileName, *inStream, hostData, 0, 0, 0, false );
 445         scanner.do_scan();
 446
 447         /* Finished, final check for errors.. */
 448         if ( gblErrorCount > 0 )
 449                 return 1;
 450
 451         /* Now send EOF to all parsers. */
 452         terminateAllParsers();
 453
 454         /* Finished, final check for errors.. */
 455         if ( gblErrorCount > 0 )
 456                 return 1;
 457
 458         if ( machineSpec == 0 && machineName == 0 )
 459                 hostData << "</host>\n";
 460
 461         if ( gblErrorCount > 0 )
 462                 return 1;
 463
 464         ostream *outputFile = 0;
 465         if ( outputFileName != 0 )
 466                 outputFile = new ofstream( outputFileName );
 467         else
 468                 outputFile = &cout;
 469
 470         /* Write the machines, then the surrounding code. */
 471         writeMachines( *outputFile, hostData.str(), inputFileName );
 472
 473         /* Close the intermediate file. */
 474         if ( outputFileName != 0 )
 475                 delete outputFile;
 476
 477         return gblErrorCount > 0;
 478 }
 479
 480 char *makeIntermedTemplate( char *baseFileName )
 481 {
 482         char *result = 0;
 483         const char *templ = "ragel-XXXXXX.xml";
 484         char *lastSlash = strrchr( baseFileName, '/' );
 485         if ( lastSlash == 0 ) {
 486                 result = new char[strlen(templ)+1];
 487                 strcpy( result, templ );
 488         }
 489         else {
 490                 int baseLen = lastSlash - baseFileName + 1;
 491                 result = new char[baseLen + strlen(templ) + 1];
 492                 memcpy( result, baseFileName, baseLen );
 493                 strcpy( result+baseLen, templ );
 494         }
 495         return result;
 496 };
 497
 498 char *openIntermed( char *inputFileName, char *outputFileName )
 499 {
 500         srand(time(0));
 501         char *result = 0;
 502
 503         /* Which filename do we use as the base? */
 504         char *baseFileName = outputFileName != 0 ? outputFileName : inputFileName;
 505
 506         /* The template for the intermediate file name. */
 507         char *intermedFileName = makeIntermedTemplate( baseFileName );
 508
 509         /* Randomize the name and try to open. */
 510         char fnChars[] = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 511         char *firstX = strrchr( intermedFileName, 'X' ) - 5;
 512         for ( int tries = 0; tries < 20; tries++ ) {
 513                 /* Choose a random name. */
 514                 for ( int x = 0; x < 6; x++ )
 515                         firstX[x] = fnChars[rand() % 52];
 516
 517                 /* Try to open the file. */
 518                 int fd = ::open( intermedFileName, O_WRONLY|O_EXCL|O_CREAT, S_IRUSR|S_IWUSR );
 519
 520                 if ( fd > 0 ) {
 521                         /* Success. Close the file immediately and return the name for use
 522                          * by the child processes. */
 523                         ::close( fd );
 524                         result = intermedFileName;
 525                         break;
 526                 }
 527
 528                 if ( errno == EACCES ) {
 529                         error() << "failed to open temp file " << intermedFileName <<
 530                                         ", access denied" << endp;
 531                 }
 532         }
 533
 534         if ( result == 0 )
 535                 error() << "abnormal error: cannot find unique name for temp file" << endp;
 536
 537         return result;
 538 }
 539
 540
 541 void cleanExit( char *intermed, int status )
 542 {
 543         unlink( intermed );
 544         exit( status );
 545 }
 546
 547 #ifndef _WIN32
 548
 549 /* If any forward slash is found in argv0 then it is assumed that the path is
 550  * explicit and the path to the backend executable should be derived from
 551  * that. Whe check that location and also go up one then inside a directory of
 552  * the same name in case we are executing from the source tree. If no forward
 553  * slash is found it is assumed the file is being run from the installed
 554  * location. The PREFIX supplied during configuration is used. */
 555 char **makePathChecksUnix( const char *argv0, const char *progName )
 556 {
 557         char **result = new char*[3];
 558         const char *lastSlash = strrchr( argv0, '/' );
 559         int numChecks = 0;
 560
 561         if ( lastSlash != 0 ) {
 562                 char *path = strdup( argv0 );
 563                 int givenPathLen = (lastSlash - argv0) + 1;
 564                 path[givenPathLen] = 0;
 565
 566                 int progNameLen = strlen(progName);
 567                 int length = givenPathLen + progNameLen + 1;
 568                 char *check = new char[length];
 569                 sprintf( check, "%s%s", path, progName );
 570                 result[numChecks++] = check;
 571
 572                 length = givenPathLen + 3 + progNameLen + 1 + progNameLen + 1;
 573                 check = new char[length];
 574                 sprintf( check, "%s../%s/%s", path, progName, progName );
 575                 result[numChecks++] = check;
 576         }
 577         else {
 578                 int prefixLen = strlen(PREFIX);
 579                 int progNameLen = strlen(progName);
 580                 int length = prefixLen + 5 + progNameLen + 1;
 581                 char *check = new char[length];
 582
 583                 sprintf( check, PREFIX "/bin/%s", progName );
 584                 result[numChecks++] = check;
 585         }
 586
 587         result[numChecks] = 0;
 588         return result;
 589 }
 590
 591
 592 void forkAndExec( const char *progName, char **pathChecks,
 593                 ArgsVector &args, char *intermed )
 594 {
 595         pid_t pid = fork();
 596         if ( pid < 0 ) {
 597                 /* Error, no child created. */
 598                 error() << "failed to fork for " << progName << endl;
 599                 cleanExit( intermed, 1 );
 600         }
 601         else if ( pid == 0 ) {
 602                 /* child */
 603                 while ( *pathChecks != 0 ) {
 604                         /* Execv does not modify argv, it just uses the const form that is
 605                          * compatible with the most code. Ours not included. */
 606                         execv( *pathChecks, (char *const*) args.data );
 607                         pathChecks += 1;
 608                 }
 609                 error() << "failed to exec " << progName << endl;
 610                 cleanExit( intermed, 1 );
 611         }
 612
 613         /* Parent process, wait for the child. */
 614         int status;
 615         wait( &status );
 616
 617         /* What happened with the child. */
 618         if ( ! WIFEXITED( status ) ) {
 619                 error() << progName << " did not exit normally" << endl;
 620                 cleanExit( intermed, 1 );
 621         }
 622
 623         if ( WEXITSTATUS(status) != 0 )
 624                 cleanExit( intermed, WEXITSTATUS(status) );
 625 }
 626
 627 #else
 628
 629 /* GetModuleFileNameEx is used to find out where the the current process's
 630  * binary is. That location is searched first. If that fails then we go up one
 631  * directory and look for the executable inside a directory of the same name
 632  * in case we are executing from the source tree.
 633  * */
 634 char **makePathChecksWin( const char *progName )
 635 {
 636         int len = 1024;
 637         char *imageFileName = new char[len];
 638         HANDLE h = GetCurrentProcess();
 639         len = GetModuleFileNameEx( h, NULL, imageFileName, len );
 640         imageFileName[len] = 0;
 641
 642         char **result = new char*[3];
 643         const char *lastSlash = strrchr( imageFileName, '\\' );
 644         int numChecks = 0;
 645
 646         assert( lastSlash != 0 );
 647         char *path = strdup( imageFileName );
 648         int givenPathLen = (lastSlash - imageFileName) + 1;
 649         path[givenPathLen] = 0;
 650
 651         int progNameLen = strlen(progName);
 652         int length = givenPathLen + progNameLen + 1;
 653         char *check = new char[length];
 654         sprintf( check, "%s%s", path, progName );
 655         result[numChecks++] = check;
 656
 657         length = givenPathLen + 3 + progNameLen + 1 + progNameLen + 1;
 658         check = new char[length];
 659         sprintf( check, "%s..\\%s\\%s", path, progName, progName );
 660         result[numChecks++] = check;
 661
 662         result[numChecks] = 0;
 663         return result;
 664 }
 665
 666 void spawn( const char *progName, char **pathChecks,
 667                 ArgsVector &args, char *intermed )
 668 {
 669         int result = 0;
 670         while ( *pathChecks != 0 ) {
 671                 //cerr << "trying to execute " << *pathChecks << endl;
 672                 result = _spawnv( _P_WAIT, *pathChecks, args.data );
 673                 if ( result >= 0 || errno != ENOENT )
 674                         break;
 675                 pathChecks += 1;
 676         }
 677
 678         if ( result < 0 ) {
 679                 error() << "failed to spawn " << progName << endl;
 680                 cleanExit( intermed, 1 );
 681         }
 682
 683         if ( result > 0 )
 684                 cleanExit( intermed, 1 );
 685 }
 686
 687 #endif
 688
 689 void execFrontend( const char *argv0, char *inputFileName, char *intermed )
 690 {
 691         /* The frontend program name. */
 692         const char *progName = "ragel";
 693
 694         frontendArgs.insert( 0, progName );
 695         frontendArgs.insert( 1, "-x" );
 696         frontendArgs.append( "-o" );
 697         frontendArgs.append( intermed );
 698         frontendArgs.append( inputFileName );
 699         frontendArgs.append( 0 );
 700
 701 #ifndef _WIN32
 702         char **pathChecks = makePathChecksUnix( argv0, progName );
 703         forkAndExec( progName, pathChecks, frontendArgs, intermed );
 704 #else
 705         char **pathChecks = makePathChecksWin( progName );
 706         spawn( progName, pathChecks, frontendArgs, intermed );
 707 #endif
 708 }
 709
 710 void execBackend( const char *argv0, char *intermed, char *outputFileName )
 711 {
 712         /* Locate the backend program */
 713         const char *progName = 0;
 714         if ( generateDot )
 715                 progName = "rlgen-dot";
 716         else {
 717                 switch ( hostLang->lang ) {
 718                         case HostLang::C:
 719                         case HostLang::D:
 720                                 progName = "rlgen-cd";
 721                                 break;
 722                         case HostLang::Java:
 723                                 progName = "rlgen-java";
 724                                 break;
 725                         case HostLang::Ruby:
 726                                 progName = "rlgen-ruby";
 727                                 break;
 728                         case HostLang::CSharp:
 729                                 progName = "rlgen-csharp";
 730                 }
 731         }
 732
 733         backendArgs.insert( 0, progName );
 734         if ( outputFileName != 0 ) {
 735                 backendArgs.append( "-o" );
 736                 backendArgs.append( outputFileName );
 737         }
 738         backendArgs.append( intermed );
 739         backendArgs.append( 0 );
 740
 741 #ifndef _WIN32
 742         char **pathChecks = makePathChecksUnix( argv0, progName );
 743         forkAndExec( progName, pathChecks, backendArgs, intermed );
 744 #else
 745         char **pathChecks = makePathChecksWin( progName );
 746         spawn( progName, pathChecks, backendArgs, intermed );
 747 #endif
 748 }
 749
 750 /* Main, process args and call yyparse to start scanning input. */
 751 int main(int argc, char **argv)
 752 {
 753         char *inputFileName = 0;
 754         char *outputFileName = 0;
 755
 756         processArgs( argc, argv, inputFileName, outputFileName );
 757
 758         /* If -M or -S are given and we're not generating a dot file then invoke
 759          * the frontend. These options are not useful with code generators. */
 760         if ( machineName != 0 || machineSpec != 0 ) {
 761                 if ( !generateDot )
 762                         frontendOnly = true;
 763         }
 764
 765         /* Require an input file. If we use standard in then we won't have a file
 766          * name on which to base the output. */
 767         if ( inputFileName == 0 )
 768                 error() << "no input file given" << endl;
 769
 770         /* Bail on argument processing errors. */
 771         if ( gblErrorCount > 0 )
 772                 exit(1);
 773
 774         /* Make sure we are not writing to the same file as the input file. */
 775         if ( inputFileName != 0 && outputFileName != 0 &&
 776                         strcmp( inputFileName, outputFileName  ) == 0 )
 777         {
 778                 error() << "output file \"" << outputFileName  <<
 779                                 "\" is the same as the input file" << endp;
 780         }
 781
 782         if ( frontendOnly )
 783                 return frontend( inputFileName, outputFileName );
 784
 785         char *intermed = openIntermed( inputFileName, outputFileName );
 786
 787         /* From here on in the cleanExit function should be used to exit. */
 788
 789         /* Run the frontend, then the backend processes. */
 790         execFrontend( argv[0], inputFileName, intermed );
 791         execBackend( argv[0], intermed, outputFileName );
 792
 793         /* Clean up the intermediate. */
 794         cleanExit( intermed, 0 );
 795
 796         return 0;
 797 }