gcc/cppmain.c

   1 /* CPP main program, using CPP Library.
   2    Copyright (C) 1995, 1997, 1998, 1999, 2000, 2001
   3    Free Software Foundation, Inc.
   4    Written by Per Bothner, 1994-95.
   5
   6 This program is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 2, or (at your option) any
   9 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19
  20  In other words, you are welcome to use, share and improve this program.
  21  You are forbidden to forbid anyone else to use, share and improve
  22  what you give them.   Help stamp out software-hoarding!  */
  23
  24 #include "config.h"
  25 #include "system.h"
  26 #include "cpplib.h"
  27 #include "intl.h"
  28
  29 /* Encapsulates state used to convert the stream of tokens coming from
  30    cpp_get_token back into a text file.  */
  31 struct printer
  32 {
  33   FILE *outf;                   /* stream to write to.  */
  34   const char *last_fname;       /* previous file name.  */
  35   const char *syshdr_flags;     /* system header flags, if any.  */
  36   unsigned int lineno;          /* line currently being written.  */
  37   unsigned char printed;        /* nonzero if something output at lineno.  */
  38 };
  39
  40 int main                PARAMS ((int, char **));
  41 static void general_init PARAMS ((const char *));
  42 static void do_preprocessing PARAMS ((int, char **));
  43 static void setup_callbacks PARAMS ((void));
  44
  45 /* General output routines.  */
  46 static void scan_buffer PARAMS ((cpp_reader *));
  47 static void check_multiline_token PARAMS ((cpp_string *));
  48 static int printer_init PARAMS ((cpp_reader *));
  49 static int dump_macro PARAMS ((cpp_reader *, cpp_hashnode *, void *));
  50
  51 static void print_line PARAMS ((const char *));
  52 static void maybe_print_line PARAMS ((unsigned int));
  53
  54 /* Callback routines for the parser.   Most of these are active only
  55    in specific modes.  */
  56 static void cb_define   PARAMS ((cpp_reader *, cpp_hashnode *));
  57 static void cb_undef    PARAMS ((cpp_reader *, cpp_hashnode *));
  58 static void cb_include  PARAMS ((cpp_reader *, const unsigned char *,
  59                                  const cpp_token *));
  60 static void cb_ident      PARAMS ((cpp_reader *, const cpp_string *));
  61 static void cb_file_change PARAMS ((cpp_reader *, const cpp_file_change *));
  62 static void cb_def_pragma PARAMS ((cpp_reader *));
  63
  64 const char *progname;           /* Needs to be global.  */
  65 static cpp_reader *pfile;       /* An opaque handle.  */
  66 static cpp_options *options;    /* Options of pfile.  */
  67 static struct printer print;
  68
  69 int
  70 main (argc, argv)
  71      int argc;
  72      char **argv;
  73 {
  74   general_init (argv[0]);
  75
  76   /* Contruct a reader with default language GNU C89.  */
  77   pfile = cpp_create_reader (CLK_GNUC89);
  78   options = cpp_get_options (pfile);
  79
  80   do_preprocessing (argc, argv);
  81
  82   /* Call to cpp_destroy () omitted for performance reasons.  */
  83   if (cpp_errors (pfile))
  84     return FATAL_EXIT_CODE;
  85
  86   return SUCCESS_EXIT_CODE;
  87 }
  88
  89 /* Store the program name, and set the locale.  */
  90 static void
  91 general_init (argv0)
  92      const char *argv0;
  93 {
  94   progname = argv0 + strlen (argv0);
  95
  96   while (progname != argv0 && ! IS_DIR_SEPARATOR (progname[-1]))
  97     --progname;
  98
  99   xmalloc_set_program_name (progname);
 100
 101 /* LC_CTYPE determines the character set used by the terminal so it
 102    has to be set to output messages correctly.  */
 103
 104 #ifdef HAVE_LC_MESSAGES
 105   setlocale (LC_CTYPE, "");
 106   setlocale (LC_MESSAGES, "");
 107 #else
 108   setlocale (LC_ALL, "");
 109 #endif
 110
 111   (void) bindtextdomain (PACKAGE, localedir);
 112   (void) textdomain (PACKAGE);
 113 }
 114
 115 /* Handle switches, preprocess and output.  */
 116 static void
 117 do_preprocessing (argc, argv)
 118      int argc;
 119      char **argv;
 120 {
 121   int argi = 1;  /* Next argument to handle.  */
 122
 123   argi += cpp_handle_options (pfile, argc - argi , argv + argi);
 124   if (CPP_FATAL_ERRORS (pfile))
 125     return;
 126
 127   if (argi < argc)
 128     cpp_fatal (pfile, "Invalid option %s", argv[argi]);
 129   else
 130     cpp_post_options (pfile);
 131
 132   if (CPP_FATAL_ERRORS (pfile))
 133     return;
 134
 135   /* If cpp_handle_options saw --help or --version on the command
 136      line, it will have set pfile->help_only to indicate this.  Exit
 137      successfully.  [The library does not exit itself, because
 138      e.g. cc1 needs to print its own --help message at this point.]  */
 139   if (options->help_only)
 140     return;
 141
 142   /* Open the output now.  We must do so even if no_output is on,
 143      because there may be other output than from the actual
 144      preprocessing (e.g. from -dM).  */
 145   if (printer_init (pfile))
 146     return;
 147
 148   setup_callbacks ();
 149
 150   if (cpp_start_read (pfile, options->in_fname))
 151     {
 152       /* A successful cpp_start_read guarantees that we can call
 153          cpp_scan_buffer_nooutput or cpp_get_token next.  */
 154       if (options->no_output)
 155         cpp_scan_buffer_nooutput (pfile, 1);
 156       else
 157         scan_buffer (pfile);
 158
 159       /* -dM command line option.  Should this be in cpp_finish?  */
 160       if (options->dump_macros == dump_only)
 161         cpp_forall_identifiers (pfile, dump_macro, NULL);
 162
 163       cpp_finish (pfile);
 164     }
 165
 166   /* Flush any pending output.  */
 167   if (print.printed)
 168     putc ('\n', print.outf);
 169
 170   if (ferror (print.outf) || fclose (print.outf))
 171     cpp_notice_from_errno (pfile, options->out_fname);
 172 }
 173
 174 /* Set up the callbacks as appropriate.  */
 175 static void
 176 setup_callbacks ()
 177 {
 178   cpp_callbacks *cb = cpp_get_callbacks (pfile);
 179
 180   if (! options->no_output)
 181     {
 182       cb->ident      = cb_ident;
 183       cb->def_pragma = cb_def_pragma;
 184       if (! options->no_line_commands)
 185         cb->file_change = cb_file_change;
 186     }
 187
 188   if (options->dump_includes)
 189     cb->include  = cb_include;
 190
 191   if (options->dump_macros == dump_names
 192       || options->dump_macros == dump_definitions)
 193     {
 194       cb->define = cb_define;
 195       cb->undef  = cb_undef;
 196       cb->poison = cb_def_pragma;
 197     }
 198 }
 199
 200 /* Writes out the preprocessed file.  Alternates between two tokens,
 201    so that we can avoid accidental token pasting.  */
 202 static void
 203 scan_buffer (pfile)
 204      cpp_reader *pfile;
 205 {
 206   unsigned int index, line;
 207   cpp_token tokens[2], *token;
 208
 209   do
 210     {
 211       for (index = 0;; index = 1 - index)
 212         {
 213           token = &tokens[index];
 214           cpp_get_token (pfile, token);
 215
 216           if (token->type == CPP_EOF)
 217             break;
 218
 219           line = cpp_get_line (pfile)->output_line;
 220           if (print.lineno != line)
 221             {
 222               unsigned int col = cpp_get_line (pfile)->col;
 223
 224               /* Supply enough whitespace to put this token in its original
 225                  column.  Don't bother trying to reconstruct tabs; we can't
 226                  get it right in general, and nothing ought to care.  (Yes,
 227                  some things do care; the fault lies with them.)  */
 228               maybe_print_line (line);
 229               if (col > 1)
 230                 {
 231                   if (token->flags & PREV_WHITE)
 232                     col--;
 233                   while (--col)
 234                     putc (' ', print.outf);
 235                 }
 236             }
 237           else if ((token->flags & (PREV_WHITE | AVOID_LPASTE))
 238                        == AVOID_LPASTE
 239                    && cpp_avoid_paste (pfile, &tokens[1 - index], token))
 240             token->flags |= PREV_WHITE;
 241
 242           cpp_output_token (token, print.outf);
 243           print.printed = 1;
 244           if (token->type == CPP_STRING || token->type == CPP_WSTRING
 245               || token->type == CPP_COMMENT)
 246             check_multiline_token (&token->val.str);
 247         }
 248     }
 249   while (cpp_pop_buffer (pfile) != 0);
 250 }
 251
 252 /* Adjust print.lineno for newlines embedded in tokens.  */
 253 static void
 254 check_multiline_token (str)
 255      cpp_string *str;
 256 {
 257   unsigned int i;
 258
 259   for (i = 0; i < str->len; i++)
 260     if (str->text[i] == '\n')
 261       print.lineno++;
 262 }
 263
 264 /* Initialize a cpp_printer structure.  As a side effect, open the
 265    output file.  */
 266 static int
 267 printer_init (pfile)
 268      cpp_reader *pfile;
 269 {
 270   print.last_fname = 0;
 271   print.lineno = 0;
 272   print.printed = 0;
 273
 274   if (options->out_fname[0] == '\0')
 275     print.outf = stdout;
 276   else
 277     {
 278       print.outf = fopen (options->out_fname, "w");
 279       if (! print.outf)
 280         {
 281           cpp_notice_from_errno (pfile, options->out_fname);
 282           return 1;
 283         }
 284     }
 285
 286   return 0;
 287 }
 288
 289 /* Newline-terminate any output line currently in progress.  If
 290    appropriate, write the current line number to the output, or pad
 291    with newlines so the output line matches the current line.  */
 292 static void
 293 maybe_print_line (line)
 294      unsigned int line;
 295 {
 296   /* End the previous line of text (probably only needed until we get
 297      multi-line tokens fixed).  */
 298   if (print.printed)
 299     {
 300       putc ('\n', print.outf);
 301       print.lineno++;
 302       print.printed = 0;
 303     }
 304
 305   if (options->no_line_commands)
 306     {
 307       print.lineno = line;
 308       return;
 309     }
 310
 311   /* print.lineno is zero if this is the first token of the file.  We
 312      handle this specially, so that a first line of "# 1 "foo.c" in
 313      file foo.i outputs just the foo.c line, and not a foo.i line.  */
 314   if (line >= print.lineno && line < print.lineno + 8 && print.lineno)
 315     {
 316       while (line > print.lineno)
 317         {
 318           putc ('\n', print.outf);
 319           print.lineno++;
 320         }
 321     }
 322   else
 323     {
 324       print.lineno = line;
 325       print_line ("");
 326     }
 327 }
 328
 329 static void
 330 print_line (special_flags)
 331   const char *special_flags;
 332 {
 333   /* End any previous line of text.  */
 334   if (print.printed)
 335     putc ('\n', print.outf);
 336   print.printed = 0;
 337
 338   fprintf (print.outf, "# %u \"%s\"%s%s\n",
 339            print.lineno, print.last_fname, special_flags, print.syshdr_flags);
 340 }
 341
 342 /* Callbacks.  */
 343
 344 static void
 345 cb_ident (pfile, str)
 346      cpp_reader *pfile ATTRIBUTE_UNUSED;
 347      const cpp_string * str;
 348 {
 349   maybe_print_line (cpp_get_line (pfile)->output_line);
 350   fprintf (print.outf, "#ident \"%s\"\n", str->text);
 351   print.lineno++;
 352 }
 353
 354 static void
 355 cb_define (pfile, node)
 356      cpp_reader *pfile;
 357      cpp_hashnode *node;
 358 {
 359   maybe_print_line (cpp_get_line (pfile)->output_line);
 360   fprintf (print.outf, "#define %s", node->name);
 361
 362   /* -dD command line option.  */
 363   if (options->dump_macros == dump_definitions)
 364     fputs ((const char *) cpp_macro_definition (pfile, node), print.outf);
 365
 366   putc ('\n', print.outf);
 367   print.lineno++;
 368 }
 369
 370 static void
 371 cb_undef (pfile, node)
 372      cpp_reader *pfile;
 373      cpp_hashnode *node;
 374 {
 375   maybe_print_line (cpp_get_line (pfile)->output_line);
 376   fprintf (print.outf, "#undef %s\n", node->name);
 377   print.lineno++;
 378 }
 379
 380 static void
 381 cb_include (pfile, dir, header)
 382      cpp_reader *pfile ATTRIBUTE_UNUSED;
 383      const unsigned char *dir;
 384      const cpp_token *header;
 385 {
 386   maybe_print_line (cpp_get_line (pfile)->output_line);
 387   fprintf (print.outf, "#%s %s\n", dir, cpp_token_as_text (pfile, header));
 388   print.lineno++;
 389 }
 390
 391 static void
 392 cb_file_change (pfile, fc)
 393      cpp_reader *pfile ATTRIBUTE_UNUSED;
 394      const cpp_file_change *fc;
 395 {
 396   /* Bring current file to correct line (except first file).  */
 397   if (fc->reason == FC_ENTER && fc->from.filename)
 398     maybe_print_line (fc->from.lineno);
 399
 400   print.last_fname = fc->to.filename;
 401   if (fc->externc)
 402     print.syshdr_flags = " 3 4";
 403   else if (fc->sysp)
 404     print.syshdr_flags = " 3";
 405   else
 406     print.syshdr_flags = "";
 407
 408   if (print.lineno)
 409     {
 410       const char *flags = "";
 411
 412       print.lineno = fc->to.lineno;
 413       if (fc->reason == FC_ENTER)
 414         flags = " 1";
 415       else if (fc->reason == FC_LEAVE)
 416         flags = " 2";
 417
 418       if (! options->no_line_commands)
 419         print_line (flags);
 420     }
 421 }
 422
 423 static void
 424 cb_def_pragma (pfile)
 425      cpp_reader *pfile;
 426 {
 427   maybe_print_line (cpp_get_line (pfile)->output_line);
 428   fputs ("#pragma ", print.outf);
 429   cpp_output_line (pfile, print.outf);
 430   print.lineno++;
 431 }
 432
 433 /* Dump out the hash table.  */
 434 static int
 435 dump_macro (pfile, node, v)
 436      cpp_reader *pfile;
 437      cpp_hashnode *node;
 438      void *v ATTRIBUTE_UNUSED;
 439 {
 440   if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
 441     {
 442       fprintf (print.outf, "#define %s", node->name);
 443       fputs ((const char *) cpp_macro_definition (pfile, node), print.outf);
 444       putc ('\n', print.outf);
 445       print.lineno++;
 446     }
 447
 448   return 1;
 449 }