2 * Copyright (c) 1996 Wolfram Schneider <wosch@FreeBSD.org>. Berlin.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 /* return year day for Easter */
39 int year; /* 0 ... abcd, NOT since 1900 */
42 int e_a, e_b, e_c, e_d, e_e,e_f, e_g, e_h, e_i, e_k,
43 e_l, e_m, e_n, e_p, e_q;
45 /* silly, but it works */
53 e_g = (e_b + 1 - e_f) / 3;
54 e_h = ((19 * e_a) + 15 + e_b - (e_d + e_g)) % 30;
57 e_l = (32 + 2 * e_e + 2 * e_i - (e_h + e_k)) % 7;
58 e_m = (e_a + 11 * e_h + 22 * e_l) / 451;
59 e_n = (e_h + e_l + 114 - (7 * e_m)) / 31;
60 e_p = (e_h + e_l + 114 - (7 * e_m)) % 31;
65 if (e_k == 0 && e_c != 0)
74 printf("%d %d %d %d %d %d %d %d %d %d %d %d %d %d %d\n", e_a , e_b , e_c , e_d , e_e , e_f , e_g , e_h , e_i , e_k , e_l , e_m , e_n , e_p , e_q);
80 /* return year day for Easter or easter depending days
81 * Match: Easter([+-][0-9]+)?
82 * e.g: Easter-2 is Good Friday (2 days before Easter)
90 register int offset = 0;
91 extern struct fixs neaster;
93 #define EASTER "easter"
94 #define EASTERNAMELEN (sizeof(EASTER) - 1)
96 if (strncasecmp(s, EASTER, EASTERNAMELEN) == 0)
98 else if ( neaster.name != NULL
99 && strncasecmp(s, neaster.name, neaster.len) == 0
106 printf("%s %d %d\n", s, year, EASTERNAMELEN);
109 /* Easter+1 or Easter-2
123 return (easter(year) + offset);