Retro68/hfsutils/strtol.c

/*
 * hfsutils - tools for reading and writing Macintosh HFS volumes
 * Copyright (C) 1996-1998 Robert Leslie
 *
 * 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 of the License, 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, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id: strtol.c,v 1.5 1998/04/11 08:27:00 rob Exp $
 */

# ifdef HAVE_CONFIG_H
#  include "config.h"
# endif

# include <stdlib.h>
# include <ctype.h>

/*
 * NAME:	strtol()
 * DESCRIPTION:	convert a string to a long integer
 */
long strtol(const char *nptr, char **endptr, int base)
{
  long result = 0;
  int negative = 0;

  /* this replacement function optimized for use with hfsutils */

  if (endptr || base)
    abort();

  while (isspace(*nptr))
    ++nptr;

  switch (*nptr)
    {
    case '-':
      negative = 1;

    case '+':
      ++nptr;
    }

  while (1)
    {
      unsigned digit;

      digit = *nptr++ - '0';
      if (digit > 9)
	break;

      result = 10 * result - digit;
    }

  return negative ? result : -result;
}