91 lines
2.4 KiB
C
91 lines
2.4 KiB
C
/*
|
|
* Copyright (C) 1993-1996 by Andrey A. Chernov, Moscow, Russia.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "calendar.h"
|
|
|
|
#define PASKHA "paskha"
|
|
#define PASKHALEN (sizeof(PASKHA) - 1)
|
|
|
|
static int paskha(int);
|
|
|
|
/* return year day for Orthodox Easter using Gauss formula */
|
|
/* (old style result) */
|
|
|
|
static int
|
|
paskha(int R) /*year*/
|
|
{
|
|
int a, b, c, d, e;
|
|
static int x = 15;
|
|
static int y = 6;
|
|
|
|
a = R % 19;
|
|
b = R % 4;
|
|
c = R % 7;
|
|
d = (19 * a + x) % 30;
|
|
e = (2 * b + 4 * c + 6 * d + y) % 7;
|
|
return (((cumdays[3] + 1) + 22) + (d + e));
|
|
}
|
|
|
|
/* return year day for Orthodox Easter depending days */
|
|
|
|
int
|
|
getpaskha(char *s, int year)
|
|
{
|
|
int offset;
|
|
|
|
if (strncasecmp(s, PASKHA, PASKHALEN) == 0)
|
|
s += PASKHALEN;
|
|
else if (npaskha.name != NULL
|
|
&& strncasecmp(s, npaskha.name, npaskha.len) == 0)
|
|
s += npaskha.len;
|
|
else
|
|
return 0;
|
|
|
|
/* Paskha+1 or Paskha-2
|
|
* ^ ^ */
|
|
|
|
switch (*s) {
|
|
|
|
case '-':
|
|
case '+':
|
|
offset = atoi(s);
|
|
break;
|
|
|
|
default:
|
|
offset = 0;
|
|
break;
|
|
}
|
|
|
|
return (paskha(year) + offset + 13 /* new style */);
|
|
}
|