xref: /freebsd-9.3-release/contrib/gperf/src/bool-array.icc

/* Inline Functions for bool-array.{h,cc}.

   Copyright (C) 1989-1998, 2002 Free Software Foundation, Inc.
   Written by Douglas C. Schmidt <schmidt@ics.uci.edu>
   and Bruno Haible <bruno@clisp.org>.

   This file is part of GNU GPERF.

   GNU GPERF 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.

   GNU GPERF 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; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

// This needs:
//#include <stdio.h>
//#include <string.h>
//#include "options.h"

/* Initializes the bit array with room for SIZE bits, numbered from
   0 to SIZE-1. */
INLINE
Bool_Array::Bool_Array (unsigned int size)
  : _size (size),
    _iteration_number (1),
    _storage_array (new unsigned int [size])
{
  memset (_storage_array, 0, size * sizeof (_storage_array[0]));
  if (option[DEBUG])
    fprintf (stderr, "\nbool array size = %d, total bytes = %d\n",
             _size,
             static_cast<unsigned int> (_size * sizeof (_storage_array[0])));
}

/* Sets the specified bit to true.
   Returns its previous value (false or true).  */
INLINE bool
Bool_Array::set_bit (unsigned int index)
{
  if (_storage_array[index] == _iteration_number)
    /* The bit was set since the last clear() call.  */
    return true;
  else
    {
      /* The last operation on this bit was clear().  Set it now.  */
      _storage_array[index] = _iteration_number;
      return false;
    }
}

/* Resets all bits to zero.  */
INLINE void
Bool_Array::clear ()
{
  /* If we wrap around it's time to zero things out again!  However, this only
     occurs once about every 2^32 iterations, so it will not happen more
     frequently than once per second.  */

  if (++_iteration_number == 0)
    {
      _iteration_number = 1;
      memset (_storage_array, 0, _size * sizeof (_storage_array[0]));
      if (option[DEBUG])
        {
          fprintf (stderr, "(re-initialized bool_array)\n");
          fflush (stderr);
        }
    }
}