/* GNU Mailutils -- a suite of utilities for electronic mail
   Copyright (C) 2011-2020 Free Software Foundation, Inc.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   This library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General
   Public License along with this library.  If not, see
   <http://www.gnu.org/licenses/>. */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdlib.h>
#include <mailutils/datetime.h>

int
mu_datetime_julianday (int year, int month, int day)
{
  int a = (14 - month) / 12;
  int y = year + 4800 - a;
  int m = month + 12*a - 3;

  return day + (153*m + 2)/5 + 365*y + y/4 - y/100 + y/400 - 32045; 
}
