lex.c

gcc-2.95.3 Linux下最常用的C编译器

  if (c == EOF)
    {
      /* Known end of constant, just append this character.  */
      ffelex_append_to_token_ (code);
      if (ffelex_raw_mode_ > 0)
	--ffelex_raw_mode_;
      return EOF;
    }

  /* Have two characters to handle.  Do the first, then leave it to the
     caller to detect anything special about the second.  */

  ffelex_append_to_token_ (code);
  if (ffelex_raw_mode_ > 0)
    --ffelex_raw_mode_;
  ffelex_backslash_reconsider_ = TRUE;
  return c;
}

/* ffelex_bad_1_ -- Issue diagnostic with one source point

   ffelex_bad_1_(FFEBAD_SOME_ERROR,ffelex_linecount_current_,column + 1);

   Creates ffewhere line and column objects for the source point, sends them
   along with the error code to ffebad, then kills the line and column
   objects before returning.  */

static void
ffelex_bad_1_ (ffebad errnum, ffewhereLineNumber ln0, ffewhereColumnNumber cn0)
{
  ffewhereLine wl0;
  ffewhereColumn wc0;

  wl0 = ffewhere_line_new (ln0);
  wc0 = ffewhere_column_new (cn0);
  ffebad_start_lex (errnum);
  ffebad_here (0, wl0, wc0);
  ffebad_finish ();
  ffewhere_line_kill (wl0);
  ffewhere_column_kill (wc0);
}

/* ffelex_bad_2_ -- Issue diagnostic with two source points

   ffelex_bad_2_(FFEBAD_SOME_ERROR,ffelex_linecount_current_,column + 1,
	 otherline,othercolumn);

   Creates ffewhere line and column objects for the source points, sends them
   along with the error code to ffebad, then kills the line and column
   objects before returning.  */

static void
ffelex_bad_2_ (ffebad errnum, ffewhereLineNumber ln0, ffewhereColumnNumber cn0,
	       ffewhereLineNumber ln1, ffewhereColumnNumber cn1)
{
  ffewhereLine wl0, wl1;
  ffewhereColumn wc0, wc1;

  wl0 = ffewhere_line_new (ln0);
  wc0 = ffewhere_column_new (cn0);
  wl1 = ffewhere_line_new (ln1);
  wc1 = ffewhere_column_new (cn1);
  ffebad_start_lex (errnum);
  ffebad_here (0, wl0, wc0);
  ffebad_here (1, wl1, wc1);
  ffebad_finish ();
  ffewhere_line_kill (wl0);
  ffewhere_column_kill (wc0);
  ffewhere_line_kill (wl1);
  ffewhere_column_kill (wc1);
}

static void
ffelex_bad_here_ (int n, ffewhereLineNumber ln0,
		  ffewhereColumnNumber cn0)
{
  ffewhereLine wl0;
  ffewhereColumn wc0;

  wl0 = ffewhere_line_new (ln0);
  wc0 = ffewhere_column_new (cn0);
  ffebad_here (n, wl0, wc0);
  ffewhere_line_kill (wl0);
  ffewhere_column_kill (wc0);
}

#if FFECOM_targetCURRENT == FFECOM_targetGCC
static int
ffelex_getc_ (FILE *finput)
{
  int c;

  if (ffelex_kludge_chars_ == NULL)
    return getc (finput);

  c = *ffelex_kludge_chars_++;
  if (c != 0)
    return c;

  ffelex_kludge_chars_ = NULL;
  return getc (finput);
}

#endif
#if FFECOM_targetCURRENT == FFECOM_targetGCC
static int
ffelex_cfebackslash_ (int *use_d, int *d, FILE *finput)
{
  register int c = getc (finput);
  register int code;
  register unsigned count;
  unsigned firstdig = 0;
  int nonnull;

  *use_d = 0;

  switch (c)
    {
    case 'x':
      if (warn_traditional)
	warning ("the meaning of `\\x' varies with -traditional");

      if (flag_traditional)
	return c;

      code = 0;
      count = 0;
      nonnull = 0;
      while (1)
	{
	  c = getc (finput);
	  if (!(c >= 'a' && c <= 'f')
	      && !(c >= 'A' && c <= 'F')
	      && !(c >= '0' && c <= '9'))
	    {
	      *use_d = 1;
	      *d = c;
	      break;
	    }
	  code *= 16;
	  if (c >= 'a' && c <= 'f')
	    code += c - 'a' + 10;
	  if (c >= 'A' && c <= 'F')
	    code += c - 'A' + 10;
	  if (c >= '0' && c <= '9')
	    code += c - '0';
	  if (code != 0 || count != 0)
	    {
	      if (count == 0)
		firstdig = code;
	      count++;
	    }
	  nonnull = 1;
	}
      if (! nonnull)
	error ("\\x used with no following hex digits");
      else if (count == 0)
	/* Digits are all 0's.  Ok.  */
	;
      else if ((count - 1) * 4 >= TYPE_PRECISION (integer_type_node)
	       || (count > 1
		   && (((unsigned) 1
			<< (TYPE_PRECISION (integer_type_node) - (count - 1)
			    * 4))
		       <= firstdig)))
	pedwarn ("hex escape out of range");
      return code;

    case '0':  case '1':  case '2':  case '3':  case '4':
    case '5':  case '6':  case '7':
      code = 0;
      count = 0;
      while ((c <= '7') && (c >= '0') && (count++ < 3))
	{
	  code = (code * 8) + (c - '0');
	  c = getc (finput);
	}
      *use_d = 1;
      *d = c;
      return code;

    case '\\': case '\'': case '"':
      return c;

    case '\n':
      ffelex_next_line_ ();
      *use_d = 2;
      return 0;

    case EOF:
      *use_d = 1;
      *d = EOF;
      return EOF;

    case 'n':
      return TARGET_NEWLINE;

    case 't':
      return TARGET_TAB;

    case 'r':
      return TARGET_CR;

    case 'f':
      return TARGET_FF;

    case 'b':
      return TARGET_BS;

    case 'a':
      if (warn_traditional)
	warning ("the meaning of `\\a' varies with -traditional");

      if (flag_traditional)
	return c;
      return TARGET_BELL;

    case 'v':
#if 0 /* Vertical tab is present in common usage compilers.  */
      if (flag_traditional)
	return c;
#endif
      return TARGET_VT;

    case 'e':
    case 'E':
      if (pedantic)
	pedwarn ("non-ANSI-standard escape sequence, `\\%c'", c);
      return 033;

    case '?':
      return c;

      /* `\(', etc, are used at beginning of line to avoid confusing Emacs.  */
    case '(':
    case '{':
    case '[':
      /* `\%' is used to prevent SCCS from getting confused.  */
    case '%':
      if (pedantic)
	pedwarn ("non-ANSI escape sequence `\\%c'", c);
      return c;
    }
  if (c >= 040 && c < 0177)
    pedwarn ("unknown escape sequence `\\%c'", c);
  else
    pedwarn ("unknown escape sequence: `\\' followed by char code 0x%x", c);
  return c;
}

#endif
/* A miniature version of the C front-end lexer.  */

#if FFECOM_targetCURRENT == FFECOM_targetGCC
static int
ffelex_cfelex_ (ffelexToken *xtoken, FILE *finput, int c)
{
  ffelexToken token;
  char buff[129];
  char *p;
  char *q;
  char *r;
  register unsigned buffer_length;

  if ((*xtoken != NULL) && !ffelex_kludge_flag_)
    ffelex_token_kill (*xtoken);

  switch (c)
    {
    case '0': case '1': case '2': case '3': case '4':
    case '5': case '6': case '7': case '8': case '9':
      buffer_length = ARRAY_SIZE (buff);
      p = &buff[0];
      q = p;
      r = &buff[buffer_length];
      for (;;)
	{
	  *p++ = c;
	  if (p >= r)
	    {
	      register unsigned bytes_used = (p - q);

	      buffer_length *= 2;
	      q = (char *)xrealloc (q, buffer_length);
	      p = &q[bytes_used];
	      r = &q[buffer_length];
	    }
	  c = ffelex_getc_ (finput);
	  if (! ISDIGIT (c))
	    break;
	}
      *p = '\0';
      token = ffelex_token_new_number (q, ffewhere_line_unknown (),
				       ffewhere_column_unknown ());

      if (q != &buff[0])
	free (q);

      break;

    case '\"':
      buffer_length = ARRAY_SIZE (buff);
      p = &buff[0];
      q = p;
      r = &buff[buffer_length];
      c = ffelex_getc_ (finput);
      for (;;)
	{
	  bool done = FALSE;
	  int use_d = 0;
	  int d;

	  switch (c)
	    {
	    case '\"':
	      c = getc (finput);
	      done = TRUE;
	      break;

	    case '\\':		/* ~~~~~ */
	      c = ffelex_cfebackslash_ (&use_d, &d, finput);
	      break;

	    case EOF:
	    case '\n':
	      fatal ("Badly formed directive -- no closing quote");
	      done = TRUE;
	      break;

	    default:
	      break;
	    }
	  if (done)
	    break;

	  if (use_d != 2)	/* 0=>c, 1=>cd, 2=>nil. */
	    {
	      *p++ = c;
	      if (p >= r)
		{
		  register unsigned bytes_used = (p - q);

		  buffer_length = bytes_used * 2;
		  q = (char *)xrealloc (q, buffer_length);
		  p = &q[bytes_used];
		  r = &q[buffer_length];
		}
	    }
	  if (use_d == 1)
	    c = d;
	  else
	    c = getc (finput);
	}
      *p = '\0';
      token = ffelex_token_new_character (q, ffewhere_line_unknown (),
					  ffewhere_column_unknown ());

      if (q != &buff[0])
	free (q);

      break;

    default:
      token = NULL;
      break;
    }

  *xtoken = token;
  return c;
}
#endif

#if FFECOM_targetCURRENT == FFECOM_targetGCC
static void
ffelex_file_pop_ (char *input_filename)
{
  if (input_file_stack->next)
    {
      struct file_stack *p = input_file_stack;
      input_file_stack = p->next;
      free (p);
      input_file_stack_tick++;
#ifdef DWARF_DEBUGGING_INFO
      if (debug_info_level == DINFO_LEVEL_VERBOSE
	  && write_symbols == DWARF_DEBUG)
	dwarfout_resume_previous_source_file (input_file_stack->line);
#endif /* DWARF_DEBUGGING_INFO */
    }
  else
    error ("#-lines for entering and leaving files don't match");

  /* Now that we've pushed or popped the input stack,
     update the name in the top element.  */
  if (input_file_stack)
    input_file_stack->name = input_filename;
}

#endif
#if FFECOM_targetCURRENT == FFECOM_targetGCC
static void
ffelex_file_push_ (int old_lineno, char *input_filename)
{
  struct file_stack *p
    = (struct file_stack *) xmalloc (sizeof (struct file_stack));

  input_file_stack->line = old_lineno;
  p->next = input_file_stack;
  p->name = input_filename;
  input_file_stack = p;
  input_file_stack_tick++;
#ifdef DWARF_DEBUGGING_INFO
  if (debug_info_level == DINFO_LEVEL_VERBOSE
      && write_symbols == DWARF_DEBUG)
    dwarfout_start_new_source_file (input_filename);
#endif /* DWARF_DEBUGGING_INFO */

  /* Now that we've pushed or popped the input stack,
     update the name in the top element.  */
  if (input_file_stack)
    input_file_stack->name = input_filename;
}
#endif

/* Prepare to finish a statement-in-progress by sending the current
   token, if any, then setting up EOS as the current token with the
   appropriate current pointer.  The caller can then move the current
   pointer before actually sending EOS, if desired, as it is in
   typical fixed-form cases.  */

static void
ffelex_prepare_eos_ ()
{
  if (ffelex_token_->type != FFELEX_typeNONE)
    {
      ffelex_backslash_ (EOF, 0);

      switch (ffelex_raw_mode_)
	{
	case -2:
	  break;

	case -1:
	  ffebad_start_lex ((ffelex_raw_char_ == '\'') ? FFEBAD_NO_CLOSING_APOSTROPHE
			    : FFEBAD_NO_CLOSING_QUOTE);
	  ffebad_here (0, ffelex_token_->where_line, ffelex_token_->where_col);
	  ffebad_here (1, ffelex_current_wl_, ffelex_current_wc_);
	  ffebad_finish ();
	  break;

	case 0:
	  break;

	default:
	  {
	    char num[20];

	    ffebad_start_lex (FFEBAD_NOT_ENOUGH_HOLLERITH_CHARS);
	    ffebad_here (0, ffelex_token_->where_line, ffelex_token_->where_col);
	    ffebad_here (1, ffelex_current_wl_, ffelex_current_wc_);
	    sprintf (num, "%lu", (unsigned long) ffelex_raw_mode_);
	    ffebad_string (num);
	    ffebad_finish ();
	    /* Make sure the token has some text, might as well fill up with spaces.  */
	    do
	      {
		ffelex_append_to_token_ (' ');
	      } while (--ffelex_raw_mode_ > 0);
	    break;
	  }
	}
      ffelex_raw_mode_ = 0;
      ffelex_send_token_ ();
    }
  ffelex_token_->type = FFELEX_typeEOS;
  ffelex_token_->where_line = ffewhere_line_use (ffelex_current_wl_);
  ffelex_token_->where_col = ffewhere_column_use (ffelex_current_wc_);
}

static void
ffelex_finish_statement_ ()
{
  if ((ffelex_number_of_tokens_ == 0)
      && (ffelex_token_->type == FFELEX_typeNONE))