1 /*
2 +----------------------------------------------------------------------+
3 | PHP Version 7 |
4 +----------------------------------------------------------------------+
5 | Copyright (c) 1997-2018 The PHP Group |
6 +----------------------------------------------------------------------+
7 | This source file is subject to version 3.01 of the PHP license, |
8 | that is bundled with this package in the file LICENSE, and is |
9 | available through the world-wide-web at the following url: |
10 | http://www.php.net/license/3_01.txt |
11 | If you did not receive a copy of the PHP license and are unable to |
12 | obtain it through the world-wide-web, please send a note to |
13 | license@php.net so we can mail you a copy immediately. |
14 +----------------------------------------------------------------------+
15 | Authors: Shane Caraveo <shane@caraveo.com> |
16 | Colin Viebrock <colin@easydns.com> |
17 | Hartmut Holzgraefe <hholzgra@php.net> |
18 +----------------------------------------------------------------------+
19 */
20
21 #include "php.h"
22 #include "php_calendar.h"
23 #include "sdncal.h"
24 #include <time.h>
25
_cal_easter(INTERNAL_FUNCTION_PARAMETERS,zend_long gm)26 static void _cal_easter(INTERNAL_FUNCTION_PARAMETERS, zend_long gm)
27 {
28
29 /* based on code by Simon Kershaw, <webmaster@ely.anglican.org> */
30
31 struct tm te;
32 zend_long year, golden, solar, lunar, pfm, dom, tmp, easter, result;
33 zend_long method = CAL_EASTER_DEFAULT;
34
35 /* Default to the current year if year parameter is not given */
36 {
37 time_t a;
38 struct tm b, *res;
39 time(&a);
40 res = php_localtime_r(&a, &b);
41 if (!res) {
42 year = 1900;
43 } else {
44 year = 1900 + b.tm_year;
45 }
46 }
47
48 if (zend_parse_parameters(ZEND_NUM_ARGS(),
49 "|ll", &year, &method) == FAILURE) {
50 return;
51 }
52
53 if (gm && (year<1970 || year>2037)) { /* out of range for timestamps */
54 php_error_docref(NULL, E_WARNING, "This function is only valid for years between 1970 and 2037 inclusive");
55 RETURN_FALSE;
56 }
57
58 golden = (year % 19) + 1; /* the Golden number */
59
60 if ((year <= 1582 && method != CAL_EASTER_ALWAYS_GREGORIAN) ||
61 (year >= 1583 && year <= 1752 && method != CAL_EASTER_ROMAN && method != CAL_EASTER_ALWAYS_GREGORIAN) ||
62 method == CAL_EASTER_ALWAYS_JULIAN) { /* JULIAN CALENDAR */
63
64 dom = (year + (year/4) + 5) % 7; /* the "Dominical number" - finding a Sunday */
65 if (dom < 0) {
66 dom += 7;
67 }
68
69 pfm = (3 - (11*golden) - 7) % 30; /* uncorrected date of the Paschal full moon */
70 if (pfm < 0) {
71 pfm += 30;
72 }
73 } else { /* GREGORIAN CALENDAR */
74 dom = (year + (year/4) - (year/100) + (year/400)) % 7; /* the "Domincal number" */
75 if (dom < 0) {
76 dom += 7;
77 }
78
79 solar = (year-1600)/100 - (year-1600)/400; /* the solar and lunar corrections */
80 lunar = (((year-1400) / 100) * 8) / 25;
81
82 pfm = (3 - (11*golden) + solar - lunar) % 30; /* uncorrected date of the Paschal full moon */
83 if (pfm < 0) {
84 pfm += 30;
85 }
86 }
87
88 if ((pfm == 29) || (pfm == 28 && golden > 11)) { /* corrected date of the Paschal full moon */
89 pfm--; /* - days after 21st March */
90 }
91
92 tmp = (4-pfm-dom) % 7;
93 if (tmp < 0) {
94 tmp += 7;
95 }
96
97 easter = pfm + tmp + 1; /* Easter as the number of days after 21st March */
98
99 if (gm) { /* return a timestamp */
100 te.tm_isdst = -1;
101 te.tm_year = year-1900;
102 te.tm_sec = 0;
103 te.tm_min = 0;
104 te.tm_hour = 0;
105
106 if (easter < 11) {
107 te.tm_mon = 2; /* March */
108 te.tm_mday = easter+21;
109 } else {
110 te.tm_mon = 3; /* April */
111 te.tm_mday = easter-10;
112 }
113 result = mktime(&te);
114 } else { /* return the days after March 21 */
115 result = easter;
116 }
117 ZVAL_LONG(return_value, result);
118 }
119
120 /* {{{ proto int easter_date([int year])
121 Return the timestamp of midnight on Easter of a given year (defaults to current year) */
PHP_FUNCTION(easter_date)122 PHP_FUNCTION(easter_date)
123 {
124 _cal_easter(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
125 }
126 /* }}} */
127
128 /* {{{ proto int easter_days([int year, [int method]])
129 Return the number of days after March 21 that Easter falls on for a given year (defaults to current year) */
PHP_FUNCTION(easter_days)130 PHP_FUNCTION(easter_days)
131 {
132 _cal_easter(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
133 }
134 /* }}} */
135
136 /*
137 * Local variables:
138 * tab-width: 4
139 * c-basic-offset: 4
140 * End:
141 */
142
