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