protoize.c

早期freebsd实现

            {
              --cwd_p;
              --path_p;
            }
          cwd_p++;
          path_p++;
          unmatched_slash_count++;
        }

      /* Find out how many directory levels in cwd were *not* matched.  */
      while (*cwd_p)
        if (*cwd_p++ == '/')
	  unmatched_slash_count++;

      /* Now we know how long the "short name" will be.
	 Reject it if longer than the input.  */
      if (unmatched_slash_count * 3 + strlen (path_p) >= filename_len)
	return filename;

      /* For each of them, put a `../' at the beginning of the short name.  */
      while (unmatched_slash_count--)
        {
	  /* Give up if the result gets to be longer
	     than the absolute path name.  */
	  if (rel_buffer + filename_len <= rel_buf_p + 3)
	    return filename;
          *rel_buf_p++ = '.';
          *rel_buf_p++ = '.';
          *rel_buf_p++ = '/';
        }

      /* Then tack on the unmatched part of the desired file's name.  */
      do
	{
	  if (rel_buffer + filename_len <= rel_buf_p)
	    return filename;
	}
      while (*rel_buf_p++ = *path_p++);

      --rel_buf_p;
      if (*(rel_buf_p-1) == '/')
        *--rel_buf_p = '\0';
      return rel_buffer;
    }
}

/* Lookup the given filename in the hash table for filenames.  If it is a
   new one, then the hash table info pointer will be null.  In this case,
   we create a new file_info record to go with the filename, and we initialize
   that record with some reasonable values.  */

/* FILENAME was const, but that causes a warning on AIX when calling stat.
   That is probably a bug in AIX, but might as well avoid the warning.  */

static file_info *
find_file (filename, do_not_stat)
     char *filename;
     int do_not_stat;
{
  hash_table_entry *hash_entry_p;

  hash_entry_p = lookup (filename_primary, filename);
  if (hash_entry_p->fip)
    return hash_entry_p->fip;
  else
    {
      struct stat stat_buf;
      file_info *file_p = (file_info *) xmalloc (sizeof (file_info));

      /* If we cannot get status on any given source file, give a warning
         and then just set its time of last modification to infinity.  */

      if (do_not_stat)
        stat_buf.st_mtime = (time_t) 0;
      else
        {
          if (my_stat (filename, &stat_buf) == -1)
            {
              fprintf (stderr, "%s: %s: can't get status: %s\n",
		       pname, shortpath (NULL, filename), sys_errlist[errno]);
              stat_buf.st_mtime = (time_t) -1;
            }
        }

      hash_entry_p->fip = file_p;
      file_p->hash_entry = hash_entry_p;
      file_p->defs_decs = NULL;
      file_p->mtime = stat_buf.st_mtime;
      return file_p;
    }
}

/* Generate a fatal error because some part of the aux_info file is
   messed up.  */

static void
aux_info_corrupted ()
{
  fprintf (stderr, "\n%s: fatal error: aux info file corrupted at line %d\n",
	   pname, current_aux_info_lineno);
  exit (1);
}

/* ??? This comment is vague.  Say what the condition is for.  */
/* Check to see that a condition is true.  This is kind of like an assert.  */

static void
check_aux_info (cond)
     int cond;
{
  if (! cond)
    aux_info_corrupted ();
}

/* Given a pointer to the closing right parenthesis for a particular formals
   list (in an aux_info file) find the corresponding left parenthesis and
   return a pointer to it.  */

static const char *
find_corresponding_lparen (p)
     const char *p;
{
  const char *q;
  int paren_depth;

  for (paren_depth = 1, q = p-1; paren_depth; q--)
    {
      switch (*q)
        {
          case ')':
            paren_depth++;
            break;
          case '(':
            paren_depth--;
            break;
        }
    }
  return ++q;
}

/* Given a line from  an aux info file, and a time at which the aux info
   file it came from was created, check to see if the item described in
   the line comes from a file which has been modified since the aux info
   file was created.  If so, return non-zero, else return zero.  */

static int
referenced_file_is_newer (l, aux_info_mtime)
     const char *l;
     time_t aux_info_mtime;
{
  const char *p;
  file_info *fi_p;
  char *filename;

  check_aux_info (l[0] == '/');
  check_aux_info (l[1] == '*');
  check_aux_info (l[2] == ' ');

  {
    const char *filename_start = p = l + 3;

    while (*p != ':')
      p++;
    filename = (char *) alloca ((size_t) (p - filename_start) + 1);
    strncpy (filename, filename_start, (size_t) (p - filename_start));
    filename[p-filename_start] = '\0';
  }

  /* Call find_file to find the file_info record associated with the file
     which contained this particular def or dec item.  Note that this call
     may cause a new file_info record to be created if this is the first time
     that we have ever known about this particular file.  */

  fi_p = find_file (abspath (invocation_filename, filename), 0);

  return (fi_p->mtime > aux_info_mtime);
}

/* Given a line of info from the aux_info file, create a new
   def_dec_info record to remember all of the important information about
   a function definition or declaration.

   Link this record onto the list of such records for the particular file in
   which it occurred in proper (descending) line number order (for now).

   If there is an identical record already on the list for the file, throw
   this one away.  Doing so takes care of the (useless and troublesome)
   duplicates which are bound to crop up due to multiple inclusions of any
   given individual header file.

   Finally, link the new def_dec record onto the list of such records
   pertaining to this particular function name.  */

static void
save_def_or_dec (l, is_syscalls)
     const char *l;
     int is_syscalls;
{
  const char *p;
  const char *semicolon_p;
  def_dec_info *def_dec_p = (def_dec_info *) xmalloc (sizeof (def_dec_info));

#ifndef UNPROTOIZE
  def_dec_p->written = 0;
#endif /* !defined (UNPROTOIZE) */

  /* Start processing the line by picking off 5 pieces of information from
     the left hand end of the line.  These are filename, line number,
     new/old/implicit flag (new = ANSI prototype format), definition or
     declaration flag, and extern/static flag).  */

  check_aux_info (l[0] == '/');
  check_aux_info (l[1] == '*');
  check_aux_info (l[2] == ' ');

  {
    const char *filename_start = p = l + 3;
    char *filename;

    while (*p != ':')
      p++;
    filename = (char *) alloca ((size_t) (p - filename_start) + 1);
    strncpy (filename, filename_start, (size_t) (p - filename_start));
    filename[p-filename_start] = '\0';

    /* Call find_file to find the file_info record associated with the file
       which contained this particular def or dec item.  Note that this call
       may cause a new file_info record to be created if this is the first time
       that we have ever known about this particular file.
  
       Note that we started out by forcing all of the base source file names
       (i.e. the names of the aux_info files with the .X stripped off) into the
       filenames hash table, and we simultaneously setup file_info records for
       all of these base file names (even if they may be useless later).
       The file_info records for all of these "base" file names (properly)
       act as file_info records for the "original" (i.e. un-included) files
       which were submitted to gcc for compilation (when the -aux-info
       option was used).  */
  
    def_dec_p->file = find_file (abspath (invocation_filename, filename), is_syscalls);
  }

  {
    const char *line_number_start = ++p;
    char line_number[10];

    while (*p != ':')
      p++;
    strncpy (line_number, line_number_start, (size_t) (p - line_number_start));
    line_number[p-line_number_start] = '\0';
    def_dec_p->line = atoi (line_number);
  }

  /* Check that this record describes a new-style, old-style, or implicit
     definition or declaration.  */

  p++;	/* Skip over the `:'. */
  check_aux_info ((*p == 'N') || (*p == 'O') || (*p == 'I'));

  /* Is this a new style (ANSI prototyped) definition or declaration? */

  def_dec_p->prototyped = (*p == 'N');

#ifndef UNPROTOIZE

  /* Is this an implicit declaration? */

  def_dec_p->is_implicit = (*p == 'I');

#endif /* !defined (UNPROTOIZE) */

  p++;

  check_aux_info ((*p == 'C') || (*p == 'F'));

  /* Is this item a function definition (F) or a declaration (C).  Note that
     we treat item taken from the syscalls file as though they were function
     definitions regardless of what the stuff in the file says.  */

  def_dec_p->is_func_def = ((*p++ == 'F') || is_syscalls);

#ifndef UNPROTOIZE
  def_dec_p->definition = 0;	/* Fill this in later if protoizing.  */
#endif /* !defined (UNPROTOIZE) */

  check_aux_info (*p++ == ' ');
  check_aux_info (*p++ == '*');
  check_aux_info (*p++ == '/');
  check_aux_info (*p++ == ' ');

#ifdef UNPROTOIZE
  check_aux_info ((!strncmp (p, "static", 6)) || (!strncmp (p, "extern", 6)));
#else /* !defined (UNPROTOIZE) */
  if (!strncmp (p, "static", 6))
    def_dec_p->is_static = -1;
  else if (!strncmp (p, "extern", 6))
    def_dec_p->is_static = 0;
  else
    check_aux_info (0);	/* Didn't find either `extern' or `static'.  */
#endif /* !defined (UNPROTOIZE) */

  {
    const char *ansi_start = p;

    p += 6;	/* Pass over the "static" or "extern".  */

    /* We are now past the initial stuff.  Search forward from here to find
       the terminating semicolon that should immediately follow the entire
       ANSI format function declaration.  */

    while (*++p != ';')
      continue;

    semicolon_p = p;

    /* Make a copy of the ansi declaration part of the line from the aux_info
       file.  */

    def_dec_p->ansi_decl
      = dupnstr (ansi_start, (size_t) ((semicolon_p+1) - ansi_start));
  }

  /* Backup and point at the final right paren of the final argument list.  */

  p--;

  /* Now isolate a whole set of formal argument lists, one-by-one.  Normally,
     there will only be one list to isolate, but there could be more.  */

  def_dec_p->f_list_count = 0;

#ifndef UNPROTOIZE
  def_dec_p->f_list_chain = NULL;
#endif /* !defined (UNPROTOIZE) */

  for (;;)
    {
      const char *left_paren_p = find_corresponding_lparen (p);
#ifndef UNPROTOIZE
      {
        f_list_chain_item *cip =
          (f_list_chain_item *) xmalloc (sizeof (f_list_chain_item));

        cip->formals_list
	  = dupnstr (left_paren_p + 1, (size_t) (p - (left_paren_p+1)));
      
        /* Add the new chain item at the head of the current list.  */

        cip->chain_next = def_dec_p->f_list_chain;
        def_dec_p->f_list_chain = cip;
      }
#endif /* !defined (UNPROTOIZE) */
      def_dec_p->f_list_count++;

      p = left_paren_p - 2;

      /* p must now point either to another right paren, or to the last
         character of the name of the function that was declared/defined.
         If p points to another right paren, then this indicates that we
         are dealing with multiple formals lists.  In that case, there
         really should be another right paren preceding this right paren.  */

      if (*p != ')')
        break;
      else
        check_aux_info (*--p == ')');
    }


  {
    const char *past_fn = p + 1;

    check_aux_info (*past_fn == ' ');

    /* Scan leftwards over the identifier that names the function.  */

    while (is_id_char (*p))
      p--;
    p++;

    /* p now points to the leftmost character of the function name.  */

    {
      char *fn_string = (char *) alloca (past_fn - p + 1);

      strncpy (fn_string, p, (size_t) (past_fn - p));
      fn_string[past_fn-p] = '\0';
      def_dec_p->hash_entry = lookup (function_name_primary, fn_string);
    }
  }

  /* Look at all of the defs and decs for this function name that we have
     collected so far.  If there is already one which is at the same
     line number in the same file, then we can discard this new def_dec_info
     record.

     As an extra assurance that any such pair of (nominally) identical
     function declarations are in fact identical, we also compare the
     ansi_decl parts of the lines from the aux_info files just to be on
     the safe side.

     This comparison will fail if (for instance) the user was playing
     messy games with the preprocessor which ultimately causes one
     function declaration in one header file to look differently when
     that file is included by two (or more) other files.  */

  {
    const def_dec_info *other;

    for (other = def_dec_p->hash_entry->ddip; other; other = other->next_for_func)
      {
        if (def_dec_p->line == other->line && def_dec_p->file == other->file)
          {
            if (strcmp (def_dec_p->ansi_decl, other->ansi_decl))
              {
                fprintf (stderr, "%s:%d: declaration of function `%s' takes different forms\n",
			 def_dec_p->file->hash_entry->symbol,
			 def_dec_p->line,
			 def_dec_p->hash_entry->symbol);
                exit (1);
              }
            free_def_dec (def_dec_p);
            return;
          }
      }
  }

#ifdef UNPROTOIZE

  /* If we are doing unprotoizing, we must now setup the pointers that will
     point to the K&R name list and to the K&R argument declarations list.

     Note that if this is only a function declaration, then we should not
     expect to find any K&R style formals list following the ANSI-style
     formals list.  This is because GCC knows that such information is
     useless in the case of function declarations (function definitions
     are a different story however).

     Since we are unprotoizing, we don't need any such lists anyway.
     All we plan to do is to delete all characters between ()'s in any
     case.  */

  def_dec_p->formal_names = NULL;