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/* Preprocess only, using cpplib.

   Copyright (C) 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004

   Free Software Foundation, Inc.

   Written by Per Bothner, 1994-95.

This program is free software; you can redistribute it and/or modify it

under the terms of the GNU General Public License as published by the

Free Software Foundation; either version 2, or (at your option) any

later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program; if not, write to the Free Software

Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

#include "config.h"

#include "system.h"

#include "coretypes.h"

#include "tm.h"

#include "cpplib.h"

#include "../libcpp/internal.h"

#include "tree.h"

#include "c-common.h"           /* For flags.  */

#include "c-pragma.h"           /* For parse_in.  */

/* Encapsulates state used to convert a stream of tokens into a text

   file.  */

static struct

{

  FILE *outf;                   /* Stream to write to.  */

  const cpp_token *prev;        /* Previous token.  */

  const cpp_token *source;      /* Source token for spacing.  */

  int src_line;                 /* Line number currently being written.  */

  unsigned char printed;        /* Nonzero if something output at line.  */

  bool first_time;              /* pp_file_change hasn't been called yet.  */

} print;

/* General output routines.  */

static void scan_translation_unit (cpp_reader *);

static void scan_translation_unit_trad (cpp_reader *);

static void account_for_newlines (const unsigned char *, size_t);

static int dump_macro (cpp_reader *, cpp_hashnode *, void *);

static void print_line (source_location, const char *);

static void maybe_print_line (source_location);

/* Callback routines for the parser.   Most of these are active only

   in specific modes.  */

static void cb_line_change (cpp_reader *, const cpp_token *, int);

static void cb_define (cpp_reader *, source_location, cpp_hashnode *);

static void cb_undef (cpp_reader *, source_location, cpp_hashnode *);

static void cb_include (cpp_reader *, source_location, const unsigned char *,

                        const char *, int, const cpp_token **);

static void cb_ident (cpp_reader *, source_location, const cpp_string *);

static void cb_def_pragma (cpp_reader *, source_location);

static void cb_read_pch (cpp_reader *pfile, const char *name,

                         int fd, const char *orig_name);

/* Preprocess and output.  */

void

preprocess_file (cpp_reader *pfile)

{

  /* A successful cpp_read_main_file guarantees that we can call

     cpp_scan_nooutput or cpp_get_token next.  */

  if (flag_no_output)

    {

      /* Scan -included buffers, then the main file.  */

      while (pfile->buffer->prev)

        cpp_scan_nooutput (pfile);

      cpp_scan_nooutput (pfile);

    }

  else if (cpp_get_options (pfile)->traditional)

    scan_translation_unit_trad (pfile);

  else

    scan_translation_unit (pfile);

  /* -dM command line option.  Should this be elsewhere?  */

  if (flag_dump_macros == 'M')

    cpp_forall_identifiers (pfile, dump_macro, NULL);

  /* Flush any pending output.  */

  if (print.printed)

    putc ('\n', print.outf);

}

/* Set up the callbacks as appropriate.  */

void

init_pp_output (FILE *out_stream)

{

  cpp_callbacks *cb = cpp_get_callbacks (parse_in);

  if (!flag_no_output)

    {

      cb->line_change = cb_line_change;

      /* Don't emit #pragma or #ident directives if we are processing

         assembly language; the assembler may choke on them.  */

      if (cpp_get_options (parse_in)->lang != CLK_ASM)

        {

          cb->ident      = cb_ident;

          cb->def_pragma = cb_def_pragma;

        }

    }

  if (flag_dump_includes)

    cb->include  = cb_include;

  if (flag_pch_preprocess)

    {

      cb->valid_pch = c_common_valid_pch;

      cb->read_pch = cb_read_pch;

    }

  if (flag_dump_macros == 'N' || flag_dump_macros == 'D')

    {

      cb->define = cb_define;

      cb->undef  = cb_undef;

    }

  /* Initialize the print structure.  Setting print.src_line to -1 here is

     a trick to guarantee that the first token of the file will cause

     a linemarker to be output by maybe_print_line.  */

  print.src_line = -1;

  print.printed = 0;

  print.prev = 0;

  print.outf = out_stream;

  print.first_time = 1;

}

/* Writes out the preprocessed file, handling spacing and paste

   avoidance issues.  */

static void

scan_translation_unit (cpp_reader *pfile)

{

  bool avoid_paste = false;

  print.source = NULL;

  for (;;)

    {

      const cpp_token *token = cpp_get_token (pfile);

      if (token->type == CPP_PADDING)

        {

          avoid_paste = true;

          if (print.source == NULL

              || (!(print.source->flags & PREV_WHITE)

                  && token->val.source == NULL))

            print.source = token->val.source;

          continue;

        }

      if (token->type == CPP_EOF)

        break;

      /* Subtle logic to output a space if and only if necessary.  */

      if (avoid_paste)

        {

          if (print.source == NULL)

            print.source = token;

          if (print.source->flags & PREV_WHITE

              || (print.prev

                  && cpp_avoid_paste (pfile, print.prev, token))

              || (print.prev == NULL && token->type == CPP_HASH))

            putc (' ', print.outf);

        }

      else if (token->flags & PREV_WHITE)

        putc (' ', print.outf);

      avoid_paste = false;

      print.source = NULL;

      print.prev = token;

      cpp_output_token (token, print.outf);

      if (token->type == CPP_COMMENT)

        account_for_newlines (token->val.str.text, token->val.str.len);

    }

}

/* Adjust print.src_line for newlines embedded in output.  */

static void

account_for_newlines (const unsigned char *str, size_t len)

{

  while (len--)

    if (*str++ == '\n')

      print.src_line++;

}

/* Writes out a traditionally preprocessed file.  */

static void

scan_translation_unit_trad (cpp_reader *pfile)

{

  while (_cpp_read_logical_line_trad (pfile))

    {

      size_t len = pfile->out.cur - pfile->out.base;

      maybe_print_line (pfile->out.first_line);

      fwrite (pfile->out.base, 1, len, print.outf);

      print.printed = 1;

      if (!CPP_OPTION (pfile, discard_comments))

        account_for_newlines (pfile->out.base, len);

    }

}

/* If the token read on logical line LINE needs to be output on a

   different line to the current one, output the required newlines or

   a line marker, and return 1.  Otherwise return 0.  */

static void

maybe_print_line (source_location src_loc)

{

  const struct line_map *map = linemap_lookup (&line_table, src_loc);

  int src_line = SOURCE_LINE (map, src_loc);

  /* End the previous line of text.  */

  if (print.printed)

    {

      putc ('\n', print.outf);

      print.src_line++;

      print.printed = 0;

    }

  if (src_line >= print.src_line && src_line < print.src_line + 8)

    {

      while (src_line > print.src_line)

        {

          putc ('\n', print.outf);

          print.src_line++;

        }

    }

  else

    print_line (src_loc, "");

}

/* Output a line marker for logical line LINE.  Special flags are "1"

   or "2" indicating entering or leaving a file.  */

static void

print_line (source_location src_loc, const char *special_flags)

{

  /* End any previous line of text.  */

  if (print.printed)

    putc ('\n', print.outf);

  print.printed = 0;

  if (!flag_no_line_commands)

    {

      const struct line_map *map = linemap_lookup (&line_table, src_loc);

      size_t to_file_len = strlen (map->to_file);

      unsigned char *to_file_quoted = alloca (to_file_len * 4 + 1);

      unsigned char *p;

      print.src_line = SOURCE_LINE (map, src_loc);

      /* cpp_quote_string does not nul-terminate, so we have to do it

         ourselves.  */

      p = cpp_quote_string (to_file_quoted,

                            (unsigned char *) map->to_file, to_file_len);

      *p = '\0';

      fprintf (print.outf, "# %u \"%s\"%s",

               print.src_line == 0 ? 1 : print.src_line,

               to_file_quoted, special_flags);

      if (map->sysp == 2)

        fputs (" 3 4", print.outf);

      else if (map->sysp == 1)

        fputs (" 3", print.outf);

      putc ('\n', print.outf);

    }

}

/* Called when a line of output is started.  TOKEN is the first token

   of the line, and at end of file will be CPP_EOF.  */

static void

cb_line_change (cpp_reader *pfile, const cpp_token *token,

                int parsing_args)

{

  source_location src_loc = token->src_loc;

  if (token->type == CPP_EOF || parsing_args)

    return;

  maybe_print_line (src_loc);

  print.prev = 0;

  print.source = 0;

  /* Supply enough spaces to put this token in its original column,

     one space per column greater than 2, since scan_translation_unit

     will provide a space if PREV_WHITE.  Don't bother trying to

     reconstruct tabs; we can't get it right in general, and nothing

     ought to care.  Some things do care; the fault lies with them.  */

  if (!CPP_OPTION (pfile, traditional))

    {

      const struct line_map *map = linemap_lookup (&line_table, src_loc);

      int spaces = SOURCE_COLUMN (map, src_loc) - 2;

      print.printed = 1;

      while (-- spaces >= 0)

        putc (' ', print.outf);

    }

}

static void

cb_ident (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,

          const cpp_string *str)

{

  maybe_print_line (line);

  fprintf (print.outf, "#ident %s\n", str->text);

  print.src_line++;

}

static void

cb_define (cpp_reader *pfile, source_location line, cpp_hashnode *node)

{

  maybe_print_line (line);

  fputs ("#define ", print.outf);

  /* 'D' is whole definition; 'N' is name only.  */

  if (flag_dump_macros == 'D')

    fputs ((const char *) cpp_macro_definition (pfile, node),

           print.outf);

  else

    fputs ((const char *) NODE_NAME (node), print.outf);

  putc ('\n', print.outf);

  print.src_line++;

}

static void

cb_undef (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,

          cpp_hashnode *node)

{

  maybe_print_line (line);

  fprintf (print.outf, "#undef %s\n", NODE_NAME (node));

  print.src_line++;

}

static void

cb_include (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,

            const unsigned char *dir, const char *header, int angle_brackets,

            const cpp_token **comments)

{

  maybe_print_line (line);

  if (angle_brackets)

    fprintf (print.outf, "#%s <%s>", dir, header);

  else

    fprintf (print.outf, "#%s \"%s\"", dir, header);

  if (comments != NULL)

    {

      while (*comments != NULL)

        {

          if ((*comments)->flags & PREV_WHITE)

            putc (' ', print.outf);

          cpp_output_token (*comments, print.outf);

          ++comments;

        }

    }

  putc ('\n', print.outf);

  print.src_line++;

}

/* Callback called when -fworking-director and -E to emit working

   directory in cpp output file.  */

void

pp_dir_change (cpp_reader *pfile ATTRIBUTE_UNUSED, const char *dir)

{

  size_t to_file_len = strlen (dir);

  unsigned char *to_file_quoted = alloca (to_file_len * 4 + 1);

  unsigned char *p;

  /* cpp_quote_string does not nul-terminate, so we have to do it ourselves.  */

  p = cpp_quote_string (to_file_quoted, (unsigned char *) dir, to_file_len);

  *p = '\0';

  fprintf (print.outf, "# 1 \"%s//\"\n", to_file_quoted);

}

/* The file name, line number or system header flags have changed, as

   described in MAP.  */

void

pp_file_change (const struct line_map *map)

{

  const char *flags = "";

  if (flag_no_line_commands)

    return;

  if (map != NULL)

    {

      if (print.first_time)

        {

          /* Avoid printing foo.i when the main file is foo.c.  */

          if (!cpp_get_options (parse_in)->preprocessed)

            print_line (map->start_location, flags);

          print.first_time = 0;

        }

      else

        {

          /* Bring current file to correct line when entering a new file.  */

          if (map->reason == LC_ENTER)

            {

              const struct line_map *from = INCLUDED_FROM (&line_table, map);

              maybe_print_line (LAST_SOURCE_LINE_LOCATION (from));

            }

          if (map->reason == LC_ENTER)

            flags = " 1";

          else if (map->reason == LC_LEAVE)

            flags = " 2";

          print_line (map->start_location, flags);

        }

    }

}

/* Copy a #pragma directive to the preprocessed output.  */

static void

cb_def_pragma (cpp_reader *pfile, source_location line)

{

  maybe_print_line (line);

  fputs ("#pragma ", print.outf);

  cpp_output_line (pfile, print.outf);

  print.src_line++;

}

/* Dump out the hash table.  */

static int

dump_macro (cpp_reader *pfile, cpp_hashnode *node, void *v ATTRIBUTE_UNUSED)

{

  if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))

    {

      fputs ("#define ", print.outf);

      fputs ((const char *) cpp_macro_definition (pfile, node),

             print.outf);

      putc ('\n', print.outf);

      print.src_line++;

    }

  return 1;

}

/* Load in the PCH file NAME, open on FD.  It was originally searched for

   by ORIG_NAME.  Also, print out a #include command so that the PCH

   file can be loaded when the preprocessed output is compiled.  */

static void

cb_read_pch (cpp_reader *pfile, const char *name,

             int fd, const char *orig_name ATTRIBUTE_UNUSED)

{

  c_common_read_pch (pfile, name, fd, orig_name);

  fprintf (print.outf, "#pragma GCC pch_preprocess \"%s\"\n", name);

  print.src_line++;

}