src/getargs.c

   1 /* Parse command line arguments for Bison.
   2
   3    Copyright (C) 1984, 1986, 1989, 1992, 2000-2013 Free Software
   4    Foundation, Inc.
   5
   6    This file is part of Bison, the GNU Compiler Compiler.
   7
   8    This program is free software: you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation, either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include <config.h>
  22 #include "system.h"
  23 #include "output.h"
  24
  25 #include <argmatch.h>
  26 #include <c-strcase.h>
  27 #include <configmake.h>
  28 #include <error.h>
  29 #include <getopt.h>
  30 #include <progname.h>
  31
  32 #include "complain.h"
  33 #include "files.h"
  34 #include "getargs.h"
  35 #include "muscle-tab.h"
  36 #include "quote.h"
  37 #include "uniqstr.h"
  38
  39 bool defines_flag;
  40 bool graph_flag;
  41 bool xml_flag;
  42 bool no_lines_flag;
  43 bool token_table_flag;
  44 bool yacc_flag; /* for -y */
  45
  46 bool nondeterministic_parser = false;
  47 bool glr_parser = false;
  48
  49 int feature_flag = feature_caret;
  50 int report_flag = report_none;
  51 int trace_flag = trace_none;
  52
  53 static struct bison_language const valid_languages[] = {
  54   { "c", "c-skel.m4", ".c", ".h", true },
  55   { "c++", "c++-skel.m4", ".cc", ".hh", true },
  56   { "java", "java-skel.m4", ".java", ".java", false },
  57   { "", "", "", "", false }
  58 };
  59
  60 int skeleton_prio = default_prio;
  61 const char *skeleton = NULL;
  62 int language_prio = default_prio;
  63 struct bison_language const *language = &valid_languages[0];
  64
  65 /** Decode an option's key.
  66  *
  67  *  \param option   option being decoded.
  68  *  \param keys     array of valid subarguments.
  69  *  \param values   array of corresponding (int) values.
  70  *  \param all      the all value.
  71  *  \param flags    the flags to update
  72  *  \param arg      the subarguments to decode.
  73  *                  If null, then activate all the flags.
  74  *  \param no       length of the potential "no-" prefix.
  75  *                  Can be 0 or 3. If 3, negate the action of the subargument.
  76  *
  77  *  If VALUE != 0 then KEY sets flags and no-KEY clears them.
  78  *  If VALUE == 0 then KEY clears all flags from \c all and no-KEY sets all
  79  *  flags from \c all.  Thus no-none = all and no-all = none.
  80  */
  81 static void
  82 flag_argmatch (const char *option,
  83                const char * const keys[], const int values[],
  84                int all, int *flags, char *arg, size_t no)
  85 {
  86   int value = XARGMATCH (option, arg + no, keys, values);
  87
  88   /* -rnone == -rno-all, and -rno-none == -rall.  */
  89   if (!value)
  90     {
  91       value = all;
  92       no = !no;
  93     }
  94
  95   if (no)
  96     *flags &= ~value;
  97   else
  98     *flags |= value;
  99 }
 100
 101 /** Decode an option's set of keys.
 102  *
 103  *  \param option   option being decoded.
 104  *  \param keys     array of valid subarguments.
 105  *  \param values   array of corresponding (int) values.
 106  *  \param all      the all value.
 107  *  \param flags    the flags to update
 108  *  \param args     comma separated list of effective subarguments to decode.
 109  *                  If 0, then activate all the flags.
 110  */
 111 static void
 112 flags_argmatch (const char *option,
 113                 const char * const keys[], const int values[],
 114                 int all, int *flags, char *args)
 115 {
 116   if (args)
 117     for (args = strtok (args, ","); args; args = strtok (NULL, ","))
 118       {
 119         size_t no = STRPREFIX_LIT ("no-", args) ? 3 : 0;
 120         flag_argmatch (option, keys,
 121                        values, all, flags, args, no);
 122       }
 123   else
 124     *flags |= all;
 125 }
 126
 127
 128 /** Decode a set of sub arguments.
 129  *
 130  *  \param FlagName  the flag familly to update.
 131  *  \param Args      the effective sub arguments to decode.
 132  *  \param All       the "all" value.
 133  *
 134  *  \arg FlagName_args   the list of keys.
 135  *  \arg FlagName_types  the list of values.
 136  *  \arg FlagName_flag   the flag to update.
 137  */
 138 #define FLAGS_ARGMATCH(FlagName, Args, All)                             \
 139   flags_argmatch ("--" #FlagName, FlagName ## _args, FlagName ## _types, \
 140                   All, &FlagName ## _flag, Args)
 141
 142
 143 /*----------------------.
 144 | --report's handling.  |
 145 `----------------------*/
 146
 147 static const char * const report_args[] =
 148 {
 149   /* In a series of synonyms, present the most meaningful first, so
 150      that argmatch_valid be more readable.  */
 151   "none",
 152   "state", "states",
 153   "itemset", "itemsets",
 154   "lookahead", "lookaheads", "look-ahead",
 155   "solved",
 156   "all",
 157   0
 158 };
 159
 160 static const int report_types[] =
 161 {
 162   report_none,
 163   report_states, report_states,
 164   report_states | report_itemsets, report_states | report_itemsets,
 165   report_states | report_lookahead_tokens,
 166   report_states | report_lookahead_tokens,
 167   report_states | report_lookahead_tokens,
 168   report_states | report_solved_conflicts,
 169   report_all
 170 };
 171
 172 ARGMATCH_VERIFY (report_args, report_types);
 173
 174
 175 /*---------------------.
 176 | --trace's handling.  |
 177 `---------------------*/
 178
 179 static const char * const trace_args[] =
 180 {
 181   "none       - no traces",
 182   "scan       - grammar scanner traces",
 183   "parse      - grammar parser traces",
 184   "automaton  - construction of the automaton",
 185   "bitsets    - use of bitsets",
 186   "grammar    - reading, reducing the grammar",
 187   "resource   - memory consumption (where available)",
 188   "sets       - grammar sets: firsts, nullable etc.",
 189   "muscles    - m4 definitions passed to the skeleton",
 190   "tools      - m4 invocation",
 191   "m4         - m4 traces",
 192   "skeleton   - skeleton postprocessing",
 193   "time       - time consumption",
 194   "ielr       - IELR conversion",
 195   "all        - all of the above",
 196   0
 197 };
 198
 199 static const int trace_types[] =
 200 {
 201   trace_none,
 202   trace_scan,
 203   trace_parse,
 204   trace_automaton,
 205   trace_bitsets,
 206   trace_grammar,
 207   trace_resource,
 208   trace_sets,
 209   trace_muscles,
 210   trace_tools,
 211   trace_m4,
 212   trace_skeleton,
 213   trace_time,
 214   trace_ielr,
 215   trace_all
 216 };
 217
 218 ARGMATCH_VERIFY (trace_args, trace_types);
 219
 220
 221 /*-----------------------.
 222 | --feature's handling.  |
 223 `-----------------------*/
 224
 225 static const char * const feature_args[] =
 226 {
 227   "none",
 228   "caret", "diagnostics-show-caret",
 229   "all",
 230   0
 231 };
 232
 233 static const int feature_types[] =
 234 {
 235   feature_none,
 236   feature_caret, feature_caret,
 237   feature_all
 238 };
 239
 240 ARGMATCH_VERIFY (feature_args, feature_types);
 241
 242 /*-------------------------------------------.
 243 | Display the help message and exit STATUS.  |
 244 `-------------------------------------------*/
 245
 246 static void usage (int) ATTRIBUTE_NORETURN;
 247
 248 static void
 249 usage (int status)
 250 {
 251   if (status != 0)
 252     fprintf (stderr, _("Try '%s --help' for more information.\n"),
 253              program_name);
 254   else
 255     {
 256       /* For ../build-aux/cross-options.pl to work, use the format:
 257                 ^  -S, --long[=ARGS] (whitespace)
 258          A --long option is required.
 259          Otherwise, add exceptions to ../build-aux/cross-options.pl.  */
 260
 261       printf (_("Usage: %s [OPTION]... FILE\n"), program_name);
 262       fputs (_("\
 263 Generate a deterministic LR or generalized LR (GLR) parser employing\n\
 264 LALR(1), IELR(1), or canonical LR(1) parser tables.  IELR(1) and\n\
 265 canonical LR(1) support is experimental.\n\
 266 \n\
 267 "), stdout);
 268
 269       fputs (_("\
 270 Mandatory arguments to long options are mandatory for short options too.\n\
 271 "), stdout);
 272       fputs (_("\
 273 The same is true for optional arguments.\n\
 274 "), stdout);
 275
 276       fputs (_("\
 277 \n\
 278 Operation modes:\n\
 279   -h, --help                 display this help and exit\n\
 280   -V, --version              output version information and exit\n\
 281       --print-localedir      output directory containing locale-dependent data\n\
 282       --print-datadir        output directory containing skeletons and XSLT\n\
 283   -y, --yacc                 emulate POSIX Yacc\n\
 284   -W, --warnings[=CATEGORY]  report the warnings falling in CATEGORY\n\
 285   -f, --feature[=FEATURE]    activate miscellaneous features\n\
 286 \n\
 287 "), stdout);
 288
 289       fputs (_("\
 290 Parser:\n\
 291   -L, --language=LANGUAGE          specify the output programming language\n\
 292   -S, --skeleton=FILE              specify the skeleton to use\n\
 293   -t, --debug                      instrument the parser for tracing\n\
 294                                    same as '-Dparse.trace'\n\
 295       --locations                  enable location support\n\
 296   -D, --define=NAME[=VALUE]        similar to '%define NAME \"VALUE\"'\n\
 297   -F, --force-define=NAME[=VALUE]  override '%define NAME \"VALUE\"'\n\
 298   -p, --name-prefix=PREFIX         prepend PREFIX to the external symbols\n\
 299                                    deprecated by '-Dapi.prefix=PREFIX'\n\
 300   -l, --no-lines                   don't generate '#line' directives\n\
 301   -k, --token-table                include a table of token names\n\
 302 "), stdout);
 303       putc ('\n', stdout);
 304
 305       /* Keep -d and --defines separate so that ../build-aux/cross-options.pl
 306        * won't assume that -d also takes an argument.  */
 307       fputs (_("\
 308 Output:\n\
 309       --defines[=FILE]       also produce a header file\n\
 310   -d                         likewise but cannot specify FILE (for POSIX Yacc)\n\
 311   -r, --report=THINGS        also produce details on the automaton\n\
 312       --report-file=FILE     write report to FILE\n\
 313   -v, --verbose              same as '--report=state'\n\
 314   -b, --file-prefix=PREFIX   specify a PREFIX for output files\n\
 315   -o, --output=FILE          leave output to FILE\n\
 316   -g, --graph[=FILE]         also output a graph of the automaton\n\
 317   -x, --xml[=FILE]           also output an XML report of the automaton\n\
 318                              (the XML schema is experimental)\n\
 319 "), stdout);
 320       putc ('\n', stdout);
 321
 322       fputs (_("\
 323 Warning categories include:\n\
 324   'midrule-values'    unset or unused midrule values\n\
 325   'yacc'              incompatibilities with POSIX Yacc\n\
 326   'conflicts-sr'      S/R conflicts (enabled by default)\n\
 327   'conflicts-rr'      R/R conflicts (enabled by default)\n\
 328   'deprecated'        obsolete constructs\n\
 329   'empty-rule'        empty rules without %empty\n\
 330   'precedence'        useless precedence and associativity\n\
 331   'other'             all other warnings (enabled by default)\n\
 332   'all'               all the warnings except 'yacc'\n\
 333   'no-CATEGORY'       turn off warnings in CATEGORY\n\
 334   'none'              turn off all the warnings\n\
 335   'error[=CATEGORY]'  treat warnings as errors\n\
 336 "), stdout);
 337       putc ('\n', stdout);
 338
 339       fputs (_("\
 340 THINGS is a list of comma separated words that can include:\n\
 341   'state'        describe the states\n\
 342   'itemset'      complete the core item sets with their closure\n\
 343   'lookahead'    explicitly associate lookahead tokens to items\n\
 344   'solved'       describe shift/reduce conflicts solving\n\
 345   'all'          include all the above information\n\
 346   'none'         disable the report\n\
 347 "), stdout);
 348       putc ('\n', stdout);
 349
 350       fputs (_("\
 351 FEATURE is a list of comma separated words that can include:\n\
 352   'caret'        show errors with carets\n\
 353   'all'          all of the above\n\
 354   'none'         disable all of the above\n\
 355   "), stdout);
 356
 357       putc ('\n', stdout);
 358       printf (_("Report bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 359       printf (_("%s home page: <%s>.\n"), PACKAGE_NAME, PACKAGE_URL);
 360       fputs (_("General help using GNU software: "
 361                "<http://www.gnu.org/gethelp/>.\n"),
 362              stdout);
 363       /* Don't output this redundant message for English locales.
 364          Note we still output for 'C' so that it gets included in the
 365          man page.  */
 366       const char *lc_messages = setlocale (LC_MESSAGES, NULL);
 367       if (lc_messages && !STREQ (lc_messages, "en_"))
 368         /* TRANSLATORS: Replace LANG_CODE in this URL with your language
 369            code <http://translationproject.org/team/LANG_CODE.html> to
 370            form one of the URLs at http://translationproject.org/team/.
 371            Otherwise, replace the entire URL with your translation team's
 372            email address.  */
 373         fputs (_("Report translation bugs to "
 374                  "<http://translationproject.org/team/>.\n"), stdout);
 375       fputs (_("For complete documentation, run: info bison.\n"), stdout);
 376     }
 377
 378   exit (status);
 379 }
 380
 381
 382 /*------------------------------.
 383 | Display the version message.  |
 384 `------------------------------*/
 385
 386 static void
 387 version (void)
 388 {
 389   /* Some efforts were made to ease the translators' task, please
 390      continue.  */
 391   printf (_("bison (GNU Bison) %s"), VERSION);
 392   putc ('\n', stdout);
 393   fputs (_("Written by Robert Corbett and Richard Stallman.\n"), stdout);
 394   putc ('\n', stdout);
 395
 396   fprintf (stdout,
 397            _("Copyright (C) %d Free Software Foundation, Inc.\n"),
 398            PACKAGE_COPYRIGHT_YEAR);
 399
 400   fputs (_("\
 401 This is free software; see the source for copying conditions.  There is NO\n\
 402 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
 403 "),
 404          stdout);
 405 }
 406
 407
 408 /*-------------------------------------.
 409 | --skeleton and --language handling.  |
 410 `--------------------------------------*/
 411
 412 void
 413 skeleton_arg (char const *arg, int prio, location loc)
 414 {
 415   if (prio < skeleton_prio)
 416     {
 417       skeleton_prio = prio;
 418       skeleton = arg;
 419     }
 420   else if (prio == skeleton_prio)
 421     complain (&loc, complaint,
 422               _("multiple skeleton declarations are invalid"));
 423 }
 424
 425 void
 426 language_argmatch (char const *arg, int prio, location loc)
 427 {
 428   char const *msg;
 429
 430   if (prio < language_prio)
 431     {
 432       int i;
 433       for (i = 0; valid_languages[i].language[0]; i++)
 434         if (c_strcasecmp (arg, valid_languages[i].language) == 0)
 435           {
 436             language_prio = prio;
 437             language = &valid_languages[i];
 438             return;
 439           }
 440       msg = _("%s: invalid language");
 441     }
 442   else if (language_prio == prio)
 443     msg = _("multiple language declarations are invalid");
 444   else
 445     return;
 446
 447   complain (&loc, complaint, msg, quotearg_colon (arg));
 448 }
 449
 450 /*----------------------.
 451 | Process the options.  |
 452 `----------------------*/
 453
 454 /* Shorts options.
 455    Should be computed from long_options.  */
 456 static char const short_options[] =
 457   "D:"
 458   "F:"
 459   "L:"
 460   "S:"
 461   "T::"
 462   "V"
 463   "W::"
 464   "b:"
 465   "d"
 466   "f::"
 467   "g::"
 468   "h"
 469   "k"
 470   "l"
 471   "o:"
 472   "p:"
 473   "r:"
 474   "t"
 475   "v"
 476   "x::"
 477   "y"
 478   ;
 479
 480 /* Values for long options that do not have single-letter equivalents.  */
 481 enum
 482 {
 483   LOCATIONS_OPTION = CHAR_MAX + 1,
 484   PRINT_LOCALEDIR_OPTION,
 485   PRINT_DATADIR_OPTION,
 486   REPORT_FILE_OPTION
 487 };
 488
 489 static struct option const long_options[] =
 490 {
 491   /* Operation modes. */
 492   { "help",            no_argument,       0,   'h' },
 493   { "version",         no_argument,       0,   'V' },
 494   { "print-localedir", no_argument,       0,   PRINT_LOCALEDIR_OPTION },
 495   { "print-datadir",   no_argument,       0,   PRINT_DATADIR_OPTION   },
 496   { "warnings",        optional_argument, 0,   'W' },
 497
 498   /* Parser. */
 499   { "name-prefix",   required_argument,   0,   'p' },
 500
 501   /* Output. */
 502   { "file-prefix", required_argument,   0,   'b' },
 503   { "output",      required_argument,   0,   'o' },
 504   { "output-file", required_argument,   0,   'o' },
 505   { "graph",       optional_argument,   0,   'g' },
 506   { "xml",         optional_argument,   0,   'x' },
 507   { "report",      required_argument,   0,   'r' },
 508   { "report-file", required_argument,   0,   REPORT_FILE_OPTION },
 509   { "verbose",     no_argument,         0,   'v' },
 510
 511   /* Hidden. */
 512   { "trace",         optional_argument,   0,     'T' },
 513
 514   /* Output.  */
 515   { "defines",     optional_argument,   0,   'd' },
 516   { "feature",     optional_argument,   0,   'f' },
 517
 518   /* Operation modes.  */
 519   { "fixed-output-files", no_argument,  0,   'y' },
 520   { "yacc",               no_argument,  0,   'y' },
 521
 522   /* Parser.  */
 523   { "debug",          no_argument,               0,   't' },
 524   { "define",         required_argument,         0,   'D' },
 525   { "force-define",   required_argument,         0,   'F' },
 526   { "locations",      no_argument,               0, LOCATIONS_OPTION },
 527   { "no-lines",       no_argument,               0,   'l' },
 528   { "skeleton",       required_argument,         0,   'S' },
 529   { "language",       required_argument,         0,   'L' },
 530   { "token-table",    no_argument,               0,   'k' },
 531
 532   {0, 0, 0, 0}
 533 };
 534
 535 /* Under DOS, there is no difference on the case.  This can be
 536    troublesome when looking for '.tab' etc.  */
 537 #ifdef MSDOS
 538 # define AS_FILE_NAME(File) (strlwr (File), (File))
 539 #else
 540 # define AS_FILE_NAME(File) (File)
 541 #endif
 542
 543 /* Build a location for the current command line argument. */
 544 static
 545 location
 546 command_line_location (void)
 547 {
 548   location res;
 549   /* "<command line>" is used in GCC's messages about -D. */
 550   boundary_set (&res.start, uniqstr_new ("<command line>"), optind - 1, -1);
 551   res.end = res.start;
 552   return res;
 553 }
 554
 555
 556 void
 557 getargs (int argc, char *argv[])
 558 {
 559   int c;
 560
 561   while ((c = getopt_long (argc, argv, short_options, long_options, NULL))
 562          != -1)
 563     switch (c)
 564       {
 565         /* ASCII Sorting for short options (i.e., upper case then
 566            lower case), and then long-only options.  */
 567
 568       case 0:
 569         /* Certain long options cause getopt_long to return 0.  */
 570         break;
 571
 572       case 'D': /* -DNAME[=(VALUE|"VALUE"|{VALUE})]. */
 573       case 'F': /* -FNAME[=(VALUE|"VALUE"|{VALUE})]. */
 574         {
 575           char *name = optarg;
 576           char *value = strchr (optarg, '=');
 577           muscle_kind kind = muscle_keyword;
 578           if (value)
 579             {
 580               char *end = value + strlen (value) - 1;
 581               *value++ = 0;
 582               if (*value == '{' && *end == '}')
 583                 {
 584                   kind = muscle_code;
 585                   ++value;
 586                   *end = 0;
 587                 }
 588               else if (*value == '"' && *end == '"')
 589                 {
 590                   kind = muscle_string;
 591                   ++value;
 592                   *end = 0;
 593                 }
 594             }
 595           muscle_percent_define_insert (name, command_line_location (),
 596                                         kind, value ? value : "",
 597                                         c == 'D' ? MUSCLE_PERCENT_DEFINE_D
 598                                                  : MUSCLE_PERCENT_DEFINE_F);
 599         }
 600         break;
 601
 602       case 'L':
 603         language_argmatch (optarg, command_line_prio,
 604                            command_line_location ());
 605         break;
 606
 607       case 'S':
 608         skeleton_arg (AS_FILE_NAME (optarg), command_line_prio,
 609                       command_line_location ());
 610         break;
 611
 612       case 'T':
 613         FLAGS_ARGMATCH (trace, optarg, trace_all);
 614         break;
 615
 616       case 'V':
 617         version ();
 618         exit (EXIT_SUCCESS);
 619
 620       case 'f':
 621         FLAGS_ARGMATCH (feature, optarg, feature_all);
 622         break;
 623
 624       case 'W':
 625         warnings_argmatch (optarg);
 626         break;
 627
 628       case 'b':
 629         spec_file_prefix = AS_FILE_NAME (optarg);
 630         break;
 631
 632       case 'd':
 633         /* Here, the -d and --defines options are differentiated.  */
 634         defines_flag = true;
 635         if (optarg)
 636           {
 637             free (spec_defines_file);
 638             spec_defines_file = xstrdup (AS_FILE_NAME (optarg));
 639           }
 640         break;
 641
 642       case 'g':
 643         graph_flag = true;
 644         if (optarg)
 645           {
 646             free (spec_graph_file);
 647             spec_graph_file = xstrdup (AS_FILE_NAME (optarg));
 648           }
 649         break;
 650
 651       case 'h':
 652         usage (EXIT_SUCCESS);
 653
 654       case 'k':
 655         token_table_flag = true;
 656         break;
 657
 658       case 'l':
 659         no_lines_flag = true;
 660         break;
 661
 662       case 'o':
 663         spec_outfile = AS_FILE_NAME (optarg);
 664         break;
 665
 666       case 'p':
 667         spec_name_prefix = optarg;
 668         break;
 669
 670       case 'r':
 671         FLAGS_ARGMATCH (report, optarg, report_all);
 672         break;
 673
 674       case 't':
 675         muscle_percent_define_insert ("parse.trace",
 676                                       command_line_location (),
 677                                       muscle_keyword, "",
 678                                       MUSCLE_PERCENT_DEFINE_D);
 679         break;
 680
 681       case 'v':
 682         report_flag |= report_states;
 683         break;
 684
 685       case 'x':
 686         xml_flag = true;
 687         if (optarg)
 688           {
 689             free (spec_xml_file);
 690             spec_xml_file = xstrdup (AS_FILE_NAME (optarg));
 691           }
 692         break;
 693
 694       case 'y':
 695         warning_argmatch ("error=yacc", 0, 6);
 696         yacc_flag = true;
 697         break;
 698
 699       case LOCATIONS_OPTION:
 700         muscle_percent_define_ensure ("locations",
 701                                       command_line_location (), true);
 702         break;
 703
 704       case PRINT_LOCALEDIR_OPTION:
 705         printf ("%s\n", LOCALEDIR);
 706         exit (EXIT_SUCCESS);
 707
 708       case PRINT_DATADIR_OPTION:
 709         printf ("%s\n", pkgdatadir ());
 710         exit (EXIT_SUCCESS);
 711
 712       case REPORT_FILE_OPTION:
 713         free (spec_verbose_file);
 714         spec_verbose_file = xstrdup (AS_FILE_NAME (optarg));
 715         break;
 716
 717       default:
 718         usage (EXIT_FAILURE);
 719       }
 720
 721   if (argc - optind != 1)
 722     {
 723       if (argc - optind < 1)
 724         error (0, 0, _("%s: missing operand"), quotearg_colon (argv[argc - 1]));
 725       else
 726         error (0, 0, _("extra operand %s"), quote (argv[optind + 1]));
 727       usage (EXIT_FAILURE);
 728     }
 729
 730   current_file = grammar_file = uniqstr_new (argv[optind]);
 731   MUSCLE_INSERT_C_STRING ("file_name", grammar_file);
 732 }
 733
 734 void
 735 tr (char *s, char from, char to)
 736 {
 737   for (; *s; s++)
 738     if (*s == from)
 739       *s = to;
 740 }