1                 : /*
       2                 :    +----------------------------------------------------------------------+
       3                 :    | PHP Version 5                                                        |
       4                 :    +----------------------------------------------------------------------+
       5                 :    | Copyright (c) 1997-2009 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                 : /* $Id: */
      21                 : 
      22                 : #include "php.h"
      23                 : #include "php_calendar.h"
      24                 : #include "sdncal.h"
      25                 : #include <time.h>
      26                 : 
      27                 : static void _cal_easter(INTERNAL_FUNCTION_PARAMETERS, int gm)
      28               7 : {
      29                 : 
      30                 :         /* based on code by Simon Kershaw, <webmaster@ely.anglican.org> */
      31                 : 
      32                 :         struct tm te;
      33                 :         long year, golden, solar, lunar, pfm, dom, tmp, easter;
      34               7 :         long method = CAL_EASTER_DEFAULT;
      35                 : 
      36                 :         /* Default to the current year if year parameter is not given */
      37                 :         {
      38                 :                 time_t a;
      39                 :                 struct tm b, *res;
      40               7 :                 time(&a);
      41               7 :                 res = php_localtime_r(&a, &b);
      42               7 :                 if (!res) {
      43               0 :                         year = 1900;
      44                 :                 } else {
      45               7 :                         year = 1900 + b.tm_year;
      46                 :                 }
      47                 :         }
      48                 : 
      49               7 :         if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC,
      50                 :                 "|ll", &year, &method) == FAILURE) {
      51               0 :                         return;
      52                 :         }
      53                 :  
      54               7 :         if (gm && (year<1970 || year>2037)) {                             /* out of range for timestamps */
      55               1 :                 php_error_docref(NULL TSRMLS_CC, E_WARNING, "This function is only valid for years between 1970 and 2037 inclusive");
      56               1 :                 RETURN_FALSE;
      57                 :         }
      58                 : 
      59               6 :         golden = (year % 19) + 1;                                       /* the Golden number */
      60                 : 
      61               7 :         if ((year <= 1582 && method != CAL_EASTER_ALWAYS_GREGORIAN) ||
      62                 :             (year >= 1583 && year <= 1752 && method != CAL_EASTER_ROMAN && method != CAL_EASTER_ALWAYS_GREGORIAN) ||
      63                 :              method == CAL_EASTER_ALWAYS_JULIAN) {              /* JULIAN CALENDAR */
      64                 :              
      65               1 :                 dom = (year + (year/4) + 5) % 7;                        /* the "Dominical number" - finding a Sunday */
      66               1 :                 if (dom < 0) {
      67               0 :                         dom += 7;
      68                 :                 }
      69                 : 
      70               1 :                 pfm = (3 - (11*golden) - 7) % 30;                       /* uncorrected date of the Paschal full moon */
      71               1 :                 if (pfm < 0) {
      72               1 :                         pfm += 30;
      73                 :                 }
      74                 :         } else {                                                        /* GREGORIAN CALENDAR */
      75               5 :                 dom = (year + (year/4) - (year/100) + (year/400)) % 7;  /* the "Domincal number" */
      76               5 :                 if (dom < 0) {
      77               0 :                         dom += 7;
      78                 :                 }
      79                 : 
      80               5 :                 solar = (year-1600)/100 - (year-1600)/400;              /* the solar and lunar corrections */
      81               5 :                 lunar = (((year-1400) / 100) * 8) / 25;
      82                 : 
      83               5 :                 pfm = (3 - (11*golden) + solar - lunar) % 30;           /* uncorrected date of the Paschal full moon */
      84               5 :                 if (pfm < 0) {
      85               5 :                         pfm += 30;
      86                 :                 }
      87                 :         }
      88                 : 
      89               6 :         if ((pfm == 29) || (pfm == 28 && golden > 11)) {             /* corrected date of the Paschal full moon */
      90               1 :                 pfm--;                                                  /* - days after 21st March                 */
      91                 :         }
      92                 : 
      93               6 :         tmp = (4-pfm-dom) % 7;
      94               6 :         if (tmp < 0) {
      95               5 :                 tmp += 7;
      96                 :         }
      97                 : 
      98               6 :         easter = pfm + tmp + 1;                                         /* Easter as the number of days after 21st March */
      99                 : 
     100               6 :         if (gm) {                                                       /* return a timestamp */
     101               3 :                 te.tm_isdst = -1;
     102               3 :                 te.tm_year = year-1900;
     103               3 :                 te.tm_sec = 0;
     104               3 :                 te.tm_min = 0;
     105               3 :                 te.tm_hour = 0;
     106                 : 
     107               3 :                 if (easter < 11) {
     108               1 :                         te.tm_mon = 2;                  /* March */
     109               1 :                         te.tm_mday = easter+21;
     110                 :                 } else {
     111               2 :                         te.tm_mon = 3;                  /* April */
     112               2 :                         te.tm_mday = easter-10;
     113                 :                 }
     114                 : 
     115               3 :                 Z_LVAL_P(return_value) = mktime(&te);
     116                 :         } else {                                                        /* return the days after March 21 */    
     117               3 :                 Z_LVAL_P(return_value) = easter;
     118                 :         }
     119                 : 
     120               6 :         Z_TYPE_P(return_value) = IS_LONG;
     121                 : 
     122                 : }
     123                 : 
     124                 : /* {{{ proto int easter_date([int year])
     125                 :    Return the timestamp of midnight on Easter of a given year (defaults to current year) */
     126                 : PHP_FUNCTION(easter_date)
     127               4 : {
     128               4 :         _cal_easter(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
     129               4 : }
     130                 : /* }}} */
     131                 : 
     132                 : /* {{{ proto int easter_days([int year, [int method]])
     133                 :    Return the number of days after March 21 that Easter falls on for a given year (defaults to current year) */
     134                 : PHP_FUNCTION(easter_days)
     135               3 : {
     136               3 :         _cal_easter(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
     137               3 : }
     138                 : /* }}} */
     139                 : 
     140                 : /*
     141                 :  * Local variables:
     142                 :  * tab-width: 4
     143                 :  * c-basic-offset: 4
     144                 :  * End:
     145                 :  */