gcc/c-family/c-ppoutput.c

   1 /* Preprocess only, using cpplib.
   2    Copyright (C) 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2007,
   3    2008, 2009, 2010 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 3, 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; see the file COPYING3.  If not see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "cpplib.h"
  24 #include "../libcpp/internal.h"
  25 #include "tree.h"
  26 #include "c-common.h"           /* For flags.  */
  27 #include "c-pragma.h"           /* For parse_in.  */
  28
  29 /* Encapsulates state used to convert a stream of tokens into a text
  30    file.  */
  31 static struct
  32 {
  33   FILE *outf;                   /* Stream to write to.  */
  34   const cpp_token *prev;        /* Previous token.  */
  35   const cpp_token *source;      /* Source token for spacing.  */
  36   int src_line;                 /* Line number currently being written.  */
  37   unsigned char printed;        /* Nonzero if something output at line.  */
  38   bool first_time;              /* pp_file_change hasn't been called yet.  */
  39   const char *src_file;         /* Current source file.  */
  40 } print;
  41
  42 /* Defined and undefined macros being queued for output with -dU at
  43    the next newline.  */
  44 typedef struct macro_queue
  45 {
  46   struct macro_queue *next;     /* Next macro in the list.  */
  47   char *macro;                  /* The name of the macro if not
  48                                    defined, the full definition if
  49                                    defined.  */
  50 } macro_queue;
  51 static macro_queue *define_queue, *undef_queue;
  52
  53 /* General output routines.  */
  54 static void scan_translation_unit (cpp_reader *);
  55 static void print_lines_directives_only (int, const void *, size_t);
  56 static void scan_translation_unit_directives_only (cpp_reader *);
  57 static void scan_translation_unit_trad (cpp_reader *);
  58 static void account_for_newlines (const unsigned char *, size_t);
  59 static int dump_macro (cpp_reader *, cpp_hashnode *, void *);
  60 static void dump_queued_macros (cpp_reader *);
  61
  62 static void print_line_1 (source_location, const char*, FILE *);
  63 static void print_line (source_location, const char *);
  64 static void maybe_print_line_1 (source_location, FILE *);
  65 static void maybe_print_line (source_location);
  66 static void do_line_change (cpp_reader *, const cpp_token *,
  67                             source_location, int);
  68
  69 /* Callback routines for the parser.   Most of these are active only
  70    in specific modes.  */
  71 static void cb_line_change (cpp_reader *, const cpp_token *, int);
  72 static void cb_define (cpp_reader *, source_location, cpp_hashnode *);
  73 static void cb_undef (cpp_reader *, source_location, cpp_hashnode *);
  74 static void cb_used_define (cpp_reader *, source_location, cpp_hashnode *);
  75 static void cb_used_undef (cpp_reader *, source_location, cpp_hashnode *);
  76 static void cb_include (cpp_reader *, source_location, const unsigned char *,
  77                         const char *, int, const cpp_token **);
  78 static void cb_ident (cpp_reader *, source_location, const cpp_string *);
  79 static void cb_def_pragma (cpp_reader *, source_location);
  80 static void cb_read_pch (cpp_reader *pfile, const char *name,
  81                          int fd, const char *orig_name);
  82
  83 /* Preprocess and output.  */
  84 void
  85 preprocess_file (cpp_reader *pfile)
  86 {
  87   /* A successful cpp_read_main_file guarantees that we can call
  88      cpp_scan_nooutput or cpp_get_token next.  */
  89   if (flag_no_output && pfile->buffer)
  90     {
  91       /* Scan -included buffers, then the main file.  */
  92       while (pfile->buffer->prev)
  93         cpp_scan_nooutput (pfile);
  94       cpp_scan_nooutput (pfile);
  95     }
  96   else if (cpp_get_options (pfile)->traditional)
  97     scan_translation_unit_trad (pfile);
  98   else if (cpp_get_options (pfile)->directives_only
  99            && !cpp_get_options (pfile)->preprocessed)
 100     scan_translation_unit_directives_only (pfile);
 101   else
 102     scan_translation_unit (pfile);
 103
 104   /* -dM command line option.  Should this be elsewhere?  */
 105   if (flag_dump_macros == 'M')
 106     cpp_forall_identifiers (pfile, dump_macro, NULL);
 107
 108   /* Flush any pending output.  */
 109   if (print.printed)
 110     putc ('\n', print.outf);
 111 }
 112
 113 /* Set up the callbacks as appropriate.  */
 114 void
 115 init_pp_output (FILE *out_stream)
 116 {
 117   cpp_callbacks *cb = cpp_get_callbacks (parse_in);
 118
 119   if (!flag_no_output)
 120     {
 121       cb->line_change = cb_line_change;
 122       /* Don't emit #pragma or #ident directives if we are processing
 123          assembly language; the assembler may choke on them.  */
 124       if (cpp_get_options (parse_in)->lang != CLK_ASM)
 125         {
 126           cb->ident      = cb_ident;
 127           cb->def_pragma = cb_def_pragma;
 128         }
 129     }
 130
 131   if (flag_dump_includes)
 132     cb->include  = cb_include;
 133
 134   if (flag_pch_preprocess)
 135     {
 136       cb->valid_pch = c_common_valid_pch;
 137       cb->read_pch = cb_read_pch;
 138     }
 139
 140   if (flag_dump_macros == 'N' || flag_dump_macros == 'D')
 141     {
 142       cb->define = cb_define;
 143       cb->undef  = cb_undef;
 144     }
 145
 146   if (flag_dump_macros == 'U')
 147     {
 148       cb->before_define = dump_queued_macros;
 149       cb->used_define = cb_used_define;
 150       cb->used_undef = cb_used_undef;
 151     }
 152
 153   /* Initialize the print structure.  */
 154   print.src_line = 1;
 155   print.printed = 0;
 156   print.prev = 0;
 157   print.outf = out_stream;
 158   print.first_time = 1;
 159   print.src_file = "";
 160 }
 161
 162 /* Writes out the preprocessed file, handling spacing and paste
 163    avoidance issues.  */
 164 static void
 165 scan_translation_unit (cpp_reader *pfile)
 166 {
 167   bool avoid_paste = false;
 168   bool do_line_adjustments
 169     = cpp_get_options (parse_in)->lang != CLK_ASM
 170       && !flag_no_line_commands;
 171   bool in_pragma = false;
 172
 173   print.source = NULL;
 174   for (;;)
 175     {
 176       source_location loc;
 177       const cpp_token *token = cpp_get_token_with_location (pfile, &loc);
 178
 179       if (token->type == CPP_PADDING)
 180         {
 181           avoid_paste = true;
 182           if (print.source == NULL
 183               || (!(print.source->flags & PREV_WHITE)
 184                   && token->val.source == NULL))
 185             print.source = token->val.source;
 186           continue;
 187         }
 188
 189       if (token->type == CPP_EOF)
 190         break;
 191
 192       /* Subtle logic to output a space if and only if necessary.  */
 193       if (avoid_paste)
 194         {
 195           int src_line = LOCATION_LINE (loc);
 196
 197           if (print.source == NULL)
 198             print.source = token;
 199
 200           if (src_line != print.src_line
 201               && do_line_adjustments
 202               && !in_pragma)
 203             {
 204               do_line_change (pfile, token, loc, false);
 205               putc (' ', print.outf);
 206             }
 207           else if (print.source->flags & PREV_WHITE
 208                    || (print.prev
 209                        && cpp_avoid_paste (pfile, print.prev, token))
 210                    || (print.prev == NULL && token->type == CPP_HASH))
 211             putc (' ', print.outf);
 212         }
 213       else if (token->flags & PREV_WHITE)
 214         {
 215           int src_line = LOCATION_LINE (loc);
 216
 217           if (src_line != print.src_line
 218               && do_line_adjustments
 219               && !in_pragma)
 220             do_line_change (pfile, token, loc, false);
 221           putc (' ', print.outf);
 222         }
 223
 224       avoid_paste = false;
 225       print.source = NULL;
 226       print.prev = token;
 227       if (token->type == CPP_PRAGMA)
 228         {
 229           const char *space;
 230           const char *name;
 231
 232           maybe_print_line (token->src_loc);
 233           fputs ("#pragma ", print.outf);
 234           c_pp_lookup_pragma (token->val.pragma, &space, &name);
 235           if (space)
 236             fprintf (print.outf, "%s %s", space, name);
 237           else
 238             fprintf (print.outf, "%s", name);
 239           print.printed = 1;
 240           in_pragma = true;
 241         }
 242       else if (token->type == CPP_PRAGMA_EOL)
 243         {
 244           maybe_print_line (token->src_loc);
 245           in_pragma = false;
 246         }
 247       else
 248         {
 249           if (cpp_get_options (parse_in)->debug)
 250               linemap_dump_location (line_table, token->src_loc,
 251                                      print.outf);
 252           cpp_output_token (token, print.outf);
 253         }
 254
 255       if (token->type == CPP_COMMENT)
 256         account_for_newlines (token->val.str.text, token->val.str.len);
 257     }
 258 }
 259
 260 static void
 261 print_lines_directives_only (int lines, const void *buf, size_t size)
 262 {
 263   print.src_line += lines;
 264   fwrite (buf, 1, size, print.outf);
 265 }
 266
 267 /* Writes out the preprocessed file, handling spacing and paste
 268    avoidance issues.  */
 269 static void
 270 scan_translation_unit_directives_only (cpp_reader *pfile)
 271 {
 272   struct _cpp_dir_only_callbacks cb;
 273
 274   cb.print_lines = print_lines_directives_only;
 275   cb.maybe_print_line = maybe_print_line;
 276
 277   _cpp_preprocess_dir_only (pfile, &cb);
 278 }
 279
 280 /* Adjust print.src_line for newlines embedded in output.  */
 281 static void
 282 account_for_newlines (const unsigned char *str, size_t len)
 283 {
 284   while (len--)
 285     if (*str++ == '\n')
 286       print.src_line++;
 287 }
 288
 289 /* Writes out a traditionally preprocessed file.  */
 290 static void
 291 scan_translation_unit_trad (cpp_reader *pfile)
 292 {
 293   while (_cpp_read_logical_line_trad (pfile))
 294     {
 295       size_t len = pfile->out.cur - pfile->out.base;
 296       maybe_print_line (pfile->out.first_line);
 297       fwrite (pfile->out.base, 1, len, print.outf);
 298       print.printed = 1;
 299       if (!CPP_OPTION (pfile, discard_comments))
 300         account_for_newlines (pfile->out.base, len);
 301     }
 302 }
 303
 304 /* If the token read on logical line LINE needs to be output on a
 305    different line to the current one, output the required newlines or
 306    a line marker, and return 1.  Otherwise return 0.  */
 307
 308 static void
 309 maybe_print_line_1 (source_location src_loc, FILE *stream)
 310 {
 311   int src_line = LOCATION_LINE (src_loc);
 312   const char *src_file = LOCATION_FILE (src_loc);
 313
 314   /* End the previous line of text.  */
 315   if (print.printed)
 316     {
 317       putc ('\n', stream);
 318       print.src_line++;
 319       print.printed = 0;
 320     }
 321
 322   if (!flag_no_line_commands
 323       && src_line >= print.src_line
 324       && src_line < print.src_line + 8
 325       && strcmp (src_file, print.src_file) == 0)
 326     {
 327       while (src_line > print.src_line)
 328         {
 329           putc ('\n', stream);
 330           print.src_line++;
 331         }
 332     }
 333   else
 334     print_line_1 (src_loc, "", stream);
 335
 336 }
 337
 338 /* If the token read on logical line LINE needs to be output on a
 339    different line to the current one, output the required newlines or
 340    a line marker, and return 1.  Otherwise return 0.  */
 341
 342 static void
 343 maybe_print_line (source_location src_loc)
 344 {
 345   if (cpp_get_options (parse_in)->debug)
 346     linemap_dump_location (line_table, src_loc,
 347                            print.outf);
 348   maybe_print_line_1 (src_loc, print.outf);
 349 }
 350
 351 /* Output a line marker for logical line LINE.  Special flags are "1"
 352    or "2" indicating entering or leaving a file.  */
 353
 354 static void
 355 print_line_1 (source_location src_loc, const char *special_flags, FILE *stream)
 356 {
 357   /* End any previous line of text.  */
 358   if (print.printed)
 359     putc ('\n', stream);
 360   print.printed = 0;
 361
 362   if (!flag_no_line_commands)
 363     {
 364       const char *file_path = LOCATION_FILE (src_loc);
 365       int sysp;
 366       size_t to_file_len = strlen (file_path);
 367       unsigned char *to_file_quoted =
 368          (unsigned char *) alloca (to_file_len * 4 + 1);
 369       unsigned char *p;
 370
 371       print.src_line = LOCATION_LINE (src_loc);
 372       print.src_file = file_path;
 373
 374       /* cpp_quote_string does not nul-terminate, so we have to do it
 375          ourselves.  */
 376       p = cpp_quote_string (to_file_quoted,
 377                             (const unsigned char *) file_path,
 378                             to_file_len);
 379       *p = '\0';
 380       fprintf (stream, "# %u \"%s\"%s",
 381                print.src_line == 0 ? 1 : print.src_line,
 382                to_file_quoted, special_flags);
 383
 384       sysp = in_system_header_at (src_loc);
 385       if (sysp == 2)
 386         fputs (" 3 4", stream);
 387       else if (sysp == 1)
 388         fputs (" 3", stream);
 389
 390       putc ('\n', stream);
 391     }
 392 }
 393
 394 /* Output a line marker for logical line LINE.  Special flags are "1"
 395    or "2" indicating entering or leaving a file.  */
 396
 397 static void
 398 print_line (source_location src_loc, const char *special_flags)
 399 {
 400     if (cpp_get_options (parse_in)->debug)
 401       linemap_dump_location (line_table, src_loc,
 402                              print.outf);
 403     print_line_1 (src_loc, special_flags, print.outf);
 404 }
 405
 406 /* Helper function for cb_line_change and scan_translation_unit.  */
 407 static void
 408 do_line_change (cpp_reader *pfile, const cpp_token *token,
 409                 source_location src_loc, int parsing_args)
 410 {
 411   if (define_queue || undef_queue)
 412     dump_queued_macros (pfile);
 413
 414   if (token->type == CPP_EOF || parsing_args)
 415     return;
 416
 417   maybe_print_line (src_loc);
 418   print.prev = 0;
 419   print.source = 0;
 420
 421   /* Supply enough spaces to put this token in its original column,
 422      one space per column greater than 2, since scan_translation_unit
 423      will provide a space if PREV_WHITE.  Don't bother trying to
 424      reconstruct tabs; we can't get it right in general, and nothing
 425      ought to care.  Some things do care; the fault lies with them.  */
 426   if (!CPP_OPTION (pfile, traditional))
 427     {
 428       int spaces = LOCATION_COLUMN (src_loc) - 2;
 429       print.printed = 1;
 430
 431       while (-- spaces >= 0)
 432         putc (' ', print.outf);
 433     }
 434 }
 435
 436 /* Called when a line of output is started.  TOKEN is the first token
 437    of the line, and at end of file will be CPP_EOF.  */
 438 static void
 439 cb_line_change (cpp_reader *pfile, const cpp_token *token,
 440                 int parsing_args)
 441 {
 442   do_line_change (pfile, token, token->src_loc, parsing_args);
 443 }
 444
 445 static void
 446 cb_ident (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
 447           const cpp_string *str)
 448 {
 449   maybe_print_line (line);
 450   fprintf (print.outf, "#ident %s\n", str->text);
 451   print.src_line++;
 452 }
 453
 454 static void
 455 cb_define (cpp_reader *pfile, source_location line, cpp_hashnode *node)
 456 {
 457   const struct line_map *map;
 458
 459   maybe_print_line (line);
 460   fputs ("#define ", print.outf);
 461
 462   /* 'D' is whole definition; 'N' is name only.  */
 463   if (flag_dump_macros == 'D')
 464     fputs ((const char *) cpp_macro_definition (pfile, node),
 465            print.outf);
 466   else
 467     fputs ((const char *) NODE_NAME (node), print.outf);
 468
 469   putc ('\n', print.outf);
 470   linemap_resolve_location (line_table, line,
 471                             LRK_MACRO_DEFINITION_LOCATION,
 472                             &map);
 473   if (LINEMAP_LINE (map) != 0)
 474     print.src_line++;
 475 }
 476
 477 static void
 478 cb_undef (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
 479           cpp_hashnode *node)
 480 {
 481   maybe_print_line (line);
 482   fprintf (print.outf, "#undef %s\n", NODE_NAME (node));
 483   print.src_line++;
 484 }
 485
 486 static void
 487 cb_used_define (cpp_reader *pfile, source_location line ATTRIBUTE_UNUSED,
 488                 cpp_hashnode *node)
 489 {
 490   macro_queue *q;
 491   if (node->flags & NODE_BUILTIN)
 492     return;
 493   q = XNEW (macro_queue);
 494   q->macro = xstrdup ((const char *) cpp_macro_definition (pfile, node));
 495   q->next = define_queue;
 496   define_queue = q;
 497 }
 498
 499 static void
 500 cb_used_undef (cpp_reader *pfile ATTRIBUTE_UNUSED,
 501                source_location line ATTRIBUTE_UNUSED,
 502                cpp_hashnode *node)
 503 {
 504   macro_queue *q;
 505   q = XNEW (macro_queue);
 506   q->macro = xstrdup ((const char *) NODE_NAME (node));
 507   q->next = undef_queue;
 508   undef_queue = q;
 509 }
 510
 511 static void
 512 dump_queued_macros (cpp_reader *pfile ATTRIBUTE_UNUSED)
 513 {
 514   macro_queue *q;
 515
 516   /* End the previous line of text.  */
 517   if (print.printed)
 518     {
 519       putc ('\n', print.outf);
 520       print.src_line++;
 521       print.printed = 0;
 522     }
 523
 524   for (q = define_queue; q;)
 525     {
 526       macro_queue *oq;
 527       fputs ("#define ", print.outf);
 528       fputs (q->macro, print.outf);
 529       putc ('\n', print.outf);
 530       print.src_line++;
 531       oq = q;
 532       q = q->next;
 533       free (oq->macro);
 534       free (oq);
 535     }
 536   define_queue = NULL;
 537   for (q = undef_queue; q;)
 538     {
 539       macro_queue *oq;
 540       fprintf (print.outf, "#undef %s\n", q->macro);
 541       print.src_line++;
 542       oq = q;
 543       q = q->next;
 544       free (oq->macro);
 545       free (oq);
 546     }
 547   undef_queue = NULL;
 548 }
 549
 550 static void
 551 cb_include (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
 552             const unsigned char *dir, const char *header, int angle_brackets,
 553             const cpp_token **comments)
 554 {
 555   maybe_print_line (line);
 556   if (angle_brackets)
 557     fprintf (print.outf, "#%s <%s>", dir, header);
 558   else
 559     fprintf (print.outf, "#%s \"%s\"", dir, header);
 560
 561   if (comments != NULL)
 562     {
 563       while (*comments != NULL)
 564         {
 565           if ((*comments)->flags & PREV_WHITE)
 566             putc (' ', print.outf);
 567           cpp_output_token (*comments, print.outf);
 568           ++comments;
 569         }
 570     }
 571
 572   putc ('\n', print.outf);
 573   print.src_line++;
 574 }
 575
 576 /* Callback called when -fworking-director and -E to emit working
 577    directory in cpp output file.  */
 578
 579 void
 580 pp_dir_change (cpp_reader *pfile ATTRIBUTE_UNUSED, const char *dir)
 581 {
 582   size_t to_file_len = strlen (dir);
 583   unsigned char *to_file_quoted =
 584      (unsigned char *) alloca (to_file_len * 4 + 1);
 585   unsigned char *p;
 586
 587   /* cpp_quote_string does not nul-terminate, so we have to do it ourselves.  */
 588   p = cpp_quote_string (to_file_quoted, (const unsigned char *) dir, to_file_len);
 589   *p = '\0';
 590   fprintf (print.outf, "# 1 \"%s//\"\n", to_file_quoted);
 591 }
 592
 593 /* The file name, line number or system header flags have changed, as
 594    described in MAP.  */
 595
 596 void
 597 pp_file_change (const struct line_map *map)
 598 {
 599   const char *flags = "";
 600
 601   if (flag_no_line_commands)
 602     return;
 603
 604   if (map != NULL)
 605     {
 606       input_location = map->start_location;
 607       if (print.first_time)
 608         {
 609           /* Avoid printing foo.i when the main file is foo.c.  */
 610           if (!cpp_get_options (parse_in)->preprocessed)
 611             print_line (map->start_location, flags);
 612           print.first_time = 0;
 613         }
 614       else
 615         {
 616           /* Bring current file to correct line when entering a new file.  */
 617           if (map->reason == LC_ENTER)
 618             {
 619               const struct line_map *from = INCLUDED_FROM (line_table, map);
 620               maybe_print_line (LAST_SOURCE_LINE_LOCATION (from));
 621             }
 622           if (map->reason == LC_ENTER)
 623             flags = " 1";
 624           else if (map->reason == LC_LEAVE)
 625             flags = " 2";
 626           print_line (map->start_location, flags);
 627         }
 628     }
 629 }
 630
 631 /* Copy a #pragma directive to the preprocessed output.  */
 632 static void
 633 cb_def_pragma (cpp_reader *pfile, source_location line)
 634 {
 635   maybe_print_line (line);
 636   fputs ("#pragma ", print.outf);
 637   cpp_output_line (pfile, print.outf);
 638   print.src_line++;
 639 }
 640
 641 /* Dump out the hash table.  */
 642 static int
 643 dump_macro (cpp_reader *pfile, cpp_hashnode *node, void *v ATTRIBUTE_UNUSED)
 644 {
 645   if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
 646     {
 647       fputs ("#define ", print.outf);
 648       fputs ((const char *) cpp_macro_definition (pfile, node),
 649              print.outf);
 650       putc ('\n', print.outf);
 651       print.src_line++;
 652     }
 653
 654   return 1;
 655 }
 656
 657 /* Load in the PCH file NAME, open on FD.  It was originally searched for
 658    by ORIG_NAME.  Also, print out a #include command so that the PCH
 659    file can be loaded when the preprocessed output is compiled.  */
 660
 661 static void
 662 cb_read_pch (cpp_reader *pfile, const char *name,
 663              int fd, const char *orig_name ATTRIBUTE_UNUSED)
 664 {
 665   c_common_read_pch (pfile, name, fd, orig_name);
 666
 667   fprintf (print.outf, "#pragma GCC pch_preprocess \"%s\"\n", name);
 668   print.src_line++;
 669 }