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 (NULL, 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           /* Special case '# <directive name>': insert a space between
 242              the # and the token.  This will prevent it from being
 243              treated as a directive when this code is re-preprocessed.
 244              XXX Should do this only at the beginning of a line, but how?  */
 245           else if (token->type == CPP_NAME && token->val.node->directive_index
 246                    && tokens[1 - index].type == CPP_HASH)
 247             token->flags |= PREV_WHITE;
 248
 249           cpp_output_token (token, print.outf);
 250           print.printed = 1;
 251           if (token->type == CPP_STRING || token->type == CPP_WSTRING
 252               || token->type == CPP_COMMENT)
 253             check_multiline_token (&token->val.str);
 254         }
 255     }
 256   while (cpp_pop_buffer (pfile) != 0);
 257 }
 258
 259 /* Adjust print.lineno for newlines embedded in tokens.  */
 260 static void
 261 check_multiline_token (str)
 262      cpp_string *str;
 263 {
 264   unsigned int i;
 265
 266   for (i = 0; i < str->len; i++)
 267     if (str->text[i] == '\n')
 268       print.lineno++;
 269 }
 270
 271 /* Initialize a cpp_printer structure.  As a side effect, open the
 272    output file.  */
 273 static int
 274 printer_init (pfile)
 275      cpp_reader *pfile;
 276 {
 277   print.last_fname = 0;
 278   print.lineno = 0;
 279   print.printed = 0;
 280
 281   if (options->out_fname[0] == '\0')
 282     print.outf = stdout;
 283   else
 284     {
 285       print.outf = fopen (options->out_fname, "w");
 286       if (! print.outf)
 287         {
 288           cpp_notice_from_errno (pfile, options->out_fname);
 289           return 1;
 290         }
 291     }
 292
 293   return 0;
 294 }
 295
 296 /* Newline-terminate any output line currently in progress.  If
 297    appropriate, write the current line number to the output, or pad
 298    with newlines so the output line matches the current line.  */
 299 static void
 300 maybe_print_line (line)
 301      unsigned int line;
 302 {
 303   /* End the previous line of text (probably only needed until we get
 304      multi-line tokens fixed).  */
 305   if (print.printed)
 306     {
 307       putc ('\n', print.outf);
 308       print.lineno++;
 309       print.printed = 0;
 310     }
 311
 312   if (options->no_line_commands)
 313     {
 314       print.lineno = line;
 315       return;
 316     }
 317
 318   /* print.lineno is zero if this is the first token of the file.  We
 319      handle this specially, so that a first line of "# 1 "foo.c" in
 320      file foo.i outputs just the foo.c line, and not a foo.i line.  */
 321   if (line >= print.lineno && line < print.lineno + 8 && print.lineno)
 322     {
 323       while (line > print.lineno)
 324         {
 325           putc ('\n', print.outf);
 326           print.lineno++;
 327         }
 328     }
 329   else
 330     {
 331       print.lineno = line;
 332       print_line ("");
 333     }
 334 }
 335
 336 static void
 337 print_line (special_flags)
 338   const char *special_flags;
 339 {
 340   /* End any previous line of text.  */
 341   if (print.printed)
 342     putc ('\n', print.outf);
 343   print.printed = 0;
 344
 345   fprintf (print.outf, "# %u \"%s\"%s%s\n",
 346            print.lineno, print.last_fname, special_flags, print.syshdr_flags);
 347 }
 348
 349 /* Callbacks.  */
 350
 351 static void
 352 cb_ident (pfile, str)
 353      cpp_reader *pfile ATTRIBUTE_UNUSED;
 354      const cpp_string * str;
 355 {
 356   maybe_print_line (cpp_get_line (pfile)->output_line);
 357   fprintf (print.outf, "#ident \"%s\"\n", str->text);
 358   print.lineno++;
 359 }
 360
 361 static void
 362 cb_define (pfile, node)
 363      cpp_reader *pfile;
 364      cpp_hashnode *node;
 365 {
 366   maybe_print_line (cpp_get_line (pfile)->output_line);
 367   fputs ("#define ", print.outf);
 368
 369   /* -dD command line option.  */
 370   if (options->dump_macros == dump_definitions)
 371     fputs ((const char *) cpp_macro_definition (pfile, node), print.outf);
 372   else
 373     fputs ((const char *) NODE_NAME (node), print.outf);
 374
 375   putc ('\n', print.outf);
 376   print.lineno++;
 377 }
 378
 379 static void
 380 cb_undef (pfile, node)
 381      cpp_reader *pfile;
 382      cpp_hashnode *node;
 383 {
 384   maybe_print_line (cpp_get_line (pfile)->output_line);
 385   fprintf (print.outf, "#undef %s\n", NODE_NAME (node));
 386   print.lineno++;
 387 }
 388
 389 static void
 390 cb_include (pfile, dir, header)
 391      cpp_reader *pfile ATTRIBUTE_UNUSED;
 392      const unsigned char *dir;
 393      const cpp_token *header;
 394 {
 395   maybe_print_line (cpp_get_line (pfile)->output_line);
 396   fprintf (print.outf, "#%s %s\n", dir, cpp_token_as_text (pfile, header));
 397   print.lineno++;
 398 }
 399
 400 static void
 401 cb_file_change (pfile, fc)
 402      cpp_reader *pfile ATTRIBUTE_UNUSED;
 403      const cpp_file_change *fc;
 404 {
 405   /* Bring current file to correct line (except first file).  */
 406   if (fc->reason == FC_ENTER && fc->from.filename)
 407     maybe_print_line (fc->from.lineno);
 408
 409   print.last_fname = fc->to.filename;
 410   if (fc->externc)
 411     print.syshdr_flags = " 3 4";
 412   else if (fc->sysp)
 413     print.syshdr_flags = " 3";
 414   else
 415     print.syshdr_flags = "";
 416
 417   if (print.lineno)
 418     {
 419       const char *flags = "";
 420
 421       print.lineno = fc->to.lineno;
 422       if (fc->reason == FC_ENTER)
 423         flags = " 1";
 424       else if (fc->reason == FC_LEAVE)
 425         flags = " 2";
 426
 427       if (! options->no_line_commands)
 428         print_line (flags);
 429     }
 430 }
 431
 432 static void
 433 cb_def_pragma (pfile)
 434      cpp_reader *pfile;
 435 {
 436   maybe_print_line (cpp_get_line (pfile)->output_line);
 437   fputs ("#pragma ", print.outf);
 438   cpp_output_line (pfile, print.outf);
 439   print.lineno++;
 440 }
 441
 442 /* Dump out the hash table.  */
 443 static int
 444 dump_macro (pfile, node, v)
 445      cpp_reader *pfile;
 446      cpp_hashnode *node;
 447      void *v ATTRIBUTE_UNUSED;
 448 {
 449   if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
 450     {
 451       fputs ("#define ", print.outf);
 452       fputs ((const char *) cpp_macro_definition (pfile, node), print.outf);
 453       putc ('\n', print.outf);
 454       print.lineno++;
 455     }
 456
 457   return 1;
 458 }