src/m4.c

   1 /* GNU m4 -- A simple macro processor
   2
   3    Copyright (C) 1989, 1990, 1991, 1992, 1993, 1994, 2004, 2005, 2006 Free
   4    Software Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19    02110-1301  USA
  20 */
  21
  22 #include "m4.h"
  23
  24 #include <getopt.h>
  25 #include <limits.h>
  26 #include <signal.h>
  27
  28 static void usage (int);
  29
  30 /* Enable sync output for /lib/cpp (-s).  */
  31 int sync_output = 0;
  32
  33 /* Debug (-d[flags]).  */
  34 int debug_level = 0;
  35
  36 /* Hash table size (should be a prime) (-Hsize).  */
  37 size_t hash_table_size = HASHMAX;
  38
  39 /* Disable GNU extensions (-G).  */
  40 int no_gnu_extensions = 0;
  41
  42 /* Prefix all builtin functions by `m4_'.  */
  43 int prefix_all_builtins = 0;
  44
  45 /* Max length of arguments in trace output (-lsize).  */
  46 int max_debug_argument_length = 0;
  47
  48 /* Suppress warnings about missing arguments.  */
  49 int suppress_warnings = 0;
  50
  51 /* If not zero, then value of exit status for warning diagnostics.  */
  52 int warning_status = 0;
  53
  54 /* Artificial limit for expansion_level in macro.c.  */
  55 int nesting_limit = 1024;
  56
  57 #ifdef ENABLE_CHANGEWORD
  58 /* User provided regexp for describing m4 words.  */
  59 const char *user_word_regexp = "";
  60 #endif
  61
  62 /* The name this program was run with. */
  63 const char *program_name;
  64
  65 struct macro_definition
  66 {
  67   struct macro_definition *next;
  68   int code;                     /* D, U or t */
  69   const char *macro;
  70 };
  71 typedef struct macro_definition macro_definition;
  72 \f
  73 /* Error handling functions.  */
  74
  75 /*-----------------------.
  76 | Wrapper around error.  |
  77 `-----------------------*/
  78
  79 void
  80 m4_error (int status, int errnum, const char *format, ...)
  81 {
  82   va_list args;
  83   va_start (args, format);
  84   verror_at_line (status, errnum, current_line ? current_file : NULL,
  85                   current_line, format, args);
  86 }
  87
  88 /*-------------------------------.
  89 | Wrapper around error_at_line.  |
  90 `-------------------------------*/
  91
  92 void
  93 m4_error_at_line (int status, int errnum, const char *file, int line,
  94                   const char *format, ...)
  95 {
  96   va_list args;
  97   va_start (args, format);
  98   verror_at_line (status, errnum, line ? file : NULL, line, format, args);
  99 }
 100
 101 #ifdef USE_STACKOVF
 102
 103 /*---------------------------------------.
 104 | Tell user stack overflowed and abort.  |
 105 `---------------------------------------*/
 106
 107 static void
 108 stackovf_handler (void)
 109 {
 110   M4ERROR ((EXIT_FAILURE, 0,
 111             "ERROR: stack overflow.  (Infinite define recursion?)"));
 112 }
 113
 114 #endif /* USE_STACKOV */
 115 \f
 116
 117 /*---------------------------------------------.
 118 | Print a usage message and exit with STATUS.  |
 119 `---------------------------------------------*/
 120
 121 static void
 122 usage (int status)
 123 {
 124   if (status != EXIT_SUCCESS)
 125     fprintf (stderr, "Try `%s --help' for more information.\n", program_name);
 126   else
 127     {
 128       printf ("Usage: %s [OPTION]... [FILE]...\n", program_name);
 129       fputs ("\
 130 Process macros in FILEs.  If no FILE or if FILE is `-', standard input\n\
 131 is read.\n\
 132 ", stdout);
 133       fputs ("\
 134 \n\
 135 Mandatory or optional arguments to long options are mandatory or optional\n\
 136 for short options too.\n\
 137 \n\
 138 Operation modes:\n\
 139       --help                   display this help and exit\n\
 140       --version                output version information and exit\n\
 141   -E, --fatal-warnings         stop execution after first warning\n\
 142   -i, --interactive            unbuffer output, ignore interrupts\n\
 143   -P, --prefix-builtins        force a `m4_' prefix to all builtins\n\
 144   -Q, --quiet, --silent        suppress some warnings for builtins\n\
 145 ", stdout);
 146 #ifdef ENABLE_CHANGEWORD
 147       fputs ("\
 148   -W, --word-regexp=REGEXP     use REGEXP for macro name syntax\n\
 149 ", stdout);
 150 #endif
 151       fputs ("\
 152 \n\
 153 Preprocessor features:\n\
 154   -D, --define=NAME[=VALUE]    define NAME as having VALUE, or empty\n\
 155   -I, --include=DIRECTORY      append DIRECTORY to include path\n\
 156   -s, --synclines              generate `#line NUM \"FILE\"' lines\n\
 157   -U, --undefine=NAME          undefine NAME\n\
 158 ", stdout);
 159       fputs ("\
 160 \n\
 161 Limits control:\n\
 162   -G, --traditional            suppress all GNU extensions\n\
 163   -H, --hashsize=PRIME         set symbol lookup hash table size [509]\n\
 164   -L, --nesting-limit=NUMBER   change artificial nesting limit [1024]\n\
 165 ", stdout);
 166       fputs ("\
 167 \n\
 168 Frozen state files:\n\
 169   -F, --freeze-state=FILE      produce a frozen state on FILE at end\n\
 170   -R, --reload-state=FILE      reload a frozen state from FILE at start\n\
 171 ", stdout);
 172       fputs ("\
 173 \n\
 174 Debugging:\n\
 175   -d, --debug[=FLAGS]          set debug level (no FLAGS implies `aeq')\n\
 176       --debugfile=FILE         redirect debug and trace output\n\
 177   -l, --arglength=NUM          restrict macro tracing size\n\
 178   -t, --trace=NAME             trace NAME when it is defined\n\
 179 ", stdout);
 180       fputs ("\
 181 \n\
 182 FLAGS is any of:\n\
 183   a   show actual arguments\n\
 184   c   show before collect, after collect and after call\n\
 185   e   show expansion\n\
 186   f   say current input file name\n\
 187   i   show changes in input files\n\
 188   l   say current input line number\n\
 189   p   show results of path searches\n\
 190   q   quote values as necessary, with a or e flag\n\
 191   t   trace for all macro calls, not only traceon'ed\n\
 192   x   add a unique macro call id, useful with c flag\n\
 193   V   shorthand for all of the above flags\n\
 194 ", stdout);
 195       fputs ("\
 196 \n\
 197 If defined, the environment variable `M4PATH' is a colon-separated list\n\
 198 of directories included after any specified by `-I'.\n\
 199 ", stdout);
 200       fputs ("\
 201 \n\
 202 Exit status is 0 for success, 1 for failure, 63 for frozen file version\n\
 203 mismatch, or whatever value was passed to the m4exit macro.\n\
 204 ", stdout);
 205       printf ("\nReport bugs to <%s>.\n", PACKAGE_BUGREPORT);
 206     }
 207   exit (status);
 208 }
 209
 210 /*--------------------------------------.
 211 | Decode options and launch execution.  |
 212 `--------------------------------------*/
 213
 214 /* For long options that have no equivalent short option, use a
 215    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
 216 enum
 217 {
 218   DEBUGFILE_OPTION = CHAR_MAX + 1,      /* no short opt */
 219   DIVERSIONS_OPTION,                    /* not quite -N, because of message */
 220
 221   HELP_OPTION,                          /* no short opt */
 222   VERSION_OPTION                        /* no short opt */
 223 };
 224
 225 static const struct option long_options[] =
 226 {
 227   {"arglength", required_argument, NULL, 'l'},
 228   {"debug", optional_argument, NULL, 'd'},
 229   {"define", required_argument, NULL, 'D'},
 230   {"error-output", required_argument, NULL, 'o'}, /* FIXME: deprecate in 2.0 */
 231   {"fatal-warnings", no_argument, NULL, 'E'},
 232   {"freeze-state", required_argument, NULL, 'F'},
 233   {"hashsize", required_argument, NULL, 'H'},
 234   {"include", required_argument, NULL, 'I'},
 235   {"interactive", no_argument, NULL, 'i'},
 236   {"nesting-limit", required_argument, NULL, 'L'},
 237   {"prefix-builtins", no_argument, NULL, 'P'},
 238   {"quiet", no_argument, NULL, 'Q'},
 239   {"reload-state", required_argument, NULL, 'R'},
 240   {"silent", no_argument, NULL, 'Q'},
 241   {"synclines", no_argument, NULL, 's'},
 242   {"trace", required_argument, NULL, 't'},
 243   {"traditional", no_argument, NULL, 'G'},
 244   {"undefine", required_argument, NULL, 'U'},
 245   {"word-regexp", required_argument, NULL, 'W'},
 246
 247   {"debugfile", required_argument, NULL, DEBUGFILE_OPTION},
 248   {"diversions", required_argument, NULL, DIVERSIONS_OPTION},
 249
 250   {"help", no_argument, NULL, HELP_OPTION},
 251   {"version", no_argument, NULL, VERSION_OPTION},
 252
 253   { NULL, 0, NULL, 0 },
 254 };
 255
 256 /* Global catchall for any errors that should affect final error status, but
 257    where we try to continue execution in the meantime.  */
 258 int retcode;
 259
 260 #ifdef ENABLE_CHANGEWORD
 261 #define OPTSTRING "B:D:EF:GH:I:L:N:PQR:S:T:U:W:d::eil:o:st:"
 262 #else
 263 #define OPTSTRING "B:D:EF:GH:I:L:N:PQR:S:T:U:d::eil:o:st:"
 264 #endif
 265
 266 int
 267 main (int argc, char *const *argv, char *const *envp)
 268 {
 269   macro_definition *head;       /* head of deferred argument list */
 270   macro_definition *tail;
 271   macro_definition *new;
 272   int optchar;                  /* option character */
 273
 274   macro_definition *defines;
 275   FILE *fp;
 276   boolean read_stdin = FALSE;
 277   boolean interactive = FALSE;
 278   const char *debugfile = NULL;
 279   const char *frozen_file_to_read = NULL;
 280   const char *frozen_file_to_write = NULL;
 281
 282   program_name = argv[0];
 283   retcode = EXIT_SUCCESS;
 284   atexit (close_stdout);
 285
 286   include_init ();
 287   debug_init ();
 288 #ifdef USE_STACKOVF
 289   setup_stackovf_trap (argv, envp, stackovf_handler);
 290 #endif
 291
 292   /* First, we decode the arguments, to size up tables and stuff.  */
 293
 294   head = tail = NULL;
 295
 296   while (optchar = getopt_long (argc, (char **) argv, OPTSTRING,
 297                                 long_options, NULL),
 298          optchar != EOF)
 299     switch (optchar)
 300       {
 301       default:
 302         usage (EXIT_FAILURE);
 303
 304       case 'B':
 305       case 'S':
 306       case 'T':
 307         /* Compatibility junk: options that other implementations
 308            support, but which we ignore as no-ops and don't list in
 309            --help.  */
 310         error (0, 0, "Warning: `m4 -%c' may be removed in a future release",
 311                optchar);
 312         break;
 313
 314       case 'N':
 315       case DIVERSIONS_OPTION:
 316         /* -N became an obsolete no-op in 1.4.x.  */
 317         error (0, 0, "Warning: `m4 %s' is deprecated",
 318                optchar == 'N' ? "-N" : "--diversions");
 319
 320       case 'D':
 321       case 'U':
 322       case 't':
 323
 324         /* Arguments that cannot be handled until later are accumulated.  */
 325
 326         new = (macro_definition *) xmalloc (sizeof (macro_definition));
 327         new->code = optchar;
 328         new->macro = optarg;
 329         new->next = NULL;
 330
 331         if (head == NULL)
 332           head = new;
 333         else
 334           tail->next = new;
 335         tail = new;
 336
 337         break;
 338
 339       case 'E':
 340         warning_status = EXIT_FAILURE;
 341         break;
 342
 343       case 'F':
 344         frozen_file_to_write = optarg;
 345         break;
 346
 347       case 'G':
 348         no_gnu_extensions = 1;
 349         break;
 350
 351       case 'H':
 352         hash_table_size = atol (optarg);
 353         if (hash_table_size == 0)
 354           hash_table_size = HASHMAX;
 355         break;
 356
 357       case 'I':
 358         add_include_directory (optarg);
 359         break;
 360
 361       case 'L':
 362         nesting_limit = atoi (optarg);
 363         break;
 364
 365       case 'P':
 366         prefix_all_builtins = 1;
 367         break;
 368
 369       case 'Q':
 370         suppress_warnings = 1;
 371         break;
 372
 373       case 'R':
 374         frozen_file_to_read = optarg;
 375         break;
 376
 377 #ifdef ENABLE_CHANGEWORD
 378       case 'W':
 379         user_word_regexp = optarg;
 380         break;
 381 #endif
 382
 383       case 'd':
 384         debug_level = debug_decode (optarg);
 385         if (debug_level < 0)
 386           {
 387             error (0, 0, "bad debug flags: `%s'", optarg);
 388             debug_level = 0;
 389           }
 390         break;
 391
 392       case 'e':
 393         error (0, 0, "Warning: `m4 -e' is deprecated, use `-i' instead");
 394         /* fall through */
 395       case 'i':
 396         interactive = TRUE;
 397         break;
 398
 399       case 'l':
 400         max_debug_argument_length = atoi (optarg);
 401         if (max_debug_argument_length <= 0)
 402           max_debug_argument_length = 0;
 403         break;
 404
 405       case 'o':
 406         /* -o/--error-output are deprecated synonyms of --debugfile,
 407            but don't issue a deprecation warning until autoconf 2.61
 408            or later is more widely established, as such a warning
 409            would interfere with all earlier versions of autoconf.  */
 410       case DEBUGFILE_OPTION:
 411         /* Don't call debug_set_output here, as it has side effects.  */
 412         debugfile = optarg;
 413         break;
 414
 415       case 's':
 416         sync_output = 1;
 417         break;
 418
 419       case VERSION_OPTION:
 420         printf ("%s\n", PACKAGE_STRING);
 421         fputs ("\
 422 Copyright (C) 2006 Free Software Foundation, Inc.\n\
 423 This is free software; see the source for copying conditions.  There is NO\n\
 424 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
 425 \n\
 426 Written by Rene' Seindal.\n\
 427 ", stdout);
 428         exit (EXIT_SUCCESS);
 429         break;
 430
 431       case HELP_OPTION:
 432         usage (EXIT_SUCCESS);
 433         break;
 434       }
 435
 436   defines = head;
 437
 438   /* Do the basic initializations.  */
 439   if (debugfile && !debug_set_output (debugfile))
 440     M4ERROR ((0, errno, "cannot set debug file `%s'", debugfile));
 441
 442   input_init ();
 443   output_init ();
 444   symtab_init ();
 445   include_env_init ();
 446
 447   if (frozen_file_to_read)
 448     reload_frozen_state (frozen_file_to_read);
 449   else
 450     builtin_init ();
 451
 452   /* Handle deferred command line macro definitions.  Must come after
 453      initialisation of the symbol table.  */
 454
 455   while (defines != NULL)
 456     {
 457       macro_definition *next;
 458       char *macro_value;
 459       symbol *sym;
 460
 461       switch (defines->code)
 462         {
 463         case 'D':
 464           macro_value = strchr (defines->macro, '=');
 465           if (macro_value == NULL)
 466             macro_value = "";
 467           else
 468             *macro_value++ = '\0';
 469           define_user_macro (defines->macro, macro_value, SYMBOL_INSERT);
 470           break;
 471
 472         case 'U':
 473           lookup_symbol (defines->macro, SYMBOL_DELETE);
 474           break;
 475
 476         case 't':
 477           sym = lookup_symbol (defines->macro, SYMBOL_INSERT);
 478           SYMBOL_TRACED (sym) = TRUE;
 479           break;
 480
 481         default:
 482           M4ERROR ((warning_status, 0,
 483                     "INTERNAL ERROR: bad code in deferred arguments"));
 484           abort ();
 485         }
 486
 487       next = defines->next;
 488       free (defines);
 489       defines = next;
 490     }
 491
 492   /* Interactive mode means unbuffered output, and interrupts ignored.  */
 493
 494   if (interactive)
 495     {
 496       signal (SIGINT, SIG_IGN);
 497       setbuf (stdout, (char *) NULL);
 498     }
 499
 500   /* Handle the various input files.  Each file is pushed on the input,
 501      and the input read.  Wrapup text is handled separately later.  */
 502
 503   if (optind == argc)
 504     {
 505       /* No point closing stdin until after wrapped text is
 506          processed.  */
 507       push_file (stdin, "stdin", FALSE);
 508       read_stdin = TRUE;
 509       expand_input ();
 510     }
 511   else
 512     for (; optind < argc; optind++)
 513       {
 514         if (strcmp (argv[optind], "-") == 0)
 515           {
 516             /* If stdin is a terminal, we want to allow 'm4 - file -'
 517                to read input from stdin twice, like GNU cat.  Besides,
 518                there is no point closing stdin before wrapped text, to
 519                minimize bugs in syscmd called from wrapped text.  */
 520             push_file (stdin, "stdin", FALSE);
 521             read_stdin = TRUE;
 522           }
 523         else
 524           {
 525             const char *name;
 526             fp = m4_path_search (argv[optind], &name);
 527             if (fp == NULL)
 528               {
 529                 error (0, errno, "%s", argv[optind]);
 530                 /* Set the status to EXIT_FAILURE, even though we
 531                    continue to process files after a missing file.  */
 532                 retcode = EXIT_FAILURE;
 533                 continue;
 534               }
 535             push_file (fp, name, TRUE);
 536             free ((char *) name);
 537           }
 538         expand_input ();
 539       }
 540 #undef NEXTARG
 541
 542   /* Now handle wrapup text.  */
 543
 544   while (pop_wrapup ())
 545     expand_input ();
 546
 547   /* Change debug stream back to stderr, to force flushing the debug
 548      stream and detect any errors it might have encountered.  Close
 549      stdin if we read from it, to detect any errors.  */
 550   debug_set_output (NULL);
 551   if (read_stdin && fclose (stdin) == EOF)
 552     {
 553       M4ERROR ((warning_status, errno, "error reading file"));
 554       retcode = EXIT_FAILURE;
 555     }
 556
 557   if (frozen_file_to_write)
 558     produce_frozen_state (frozen_file_to_write);
 559   else
 560     {
 561       make_diversion (0);
 562       undivert_all ();
 563     }
 564   exit (retcode);
 565 }