1 /*
2 ******************************************************************************
3 * Copyright (C) 2003-2011, International Business Machines Corporation
4 * and others. All Rights Reserved.
5 ******************************************************************************
6 *
7 * File ISLAMCAL.H
8 *
9 * Modification History:
10 *
11 * Date Name Description
12 * 10/14/2003 srl ported from java IslamicCalendar
13 *****************************************************************************
14 */
15
16 #include "islamcal.h"
17
18 #if !UCONFIG_NO_FORMATTING
19
20 #include "umutex.h"
21 #include <float.h>
22 #include "gregoimp.h" // Math
23 #include "astro.h" // CalendarAstronomer
24 #include "uhash.h"
25 #include "ucln_in.h"
26
27 static const UDate HIJRA_MILLIS = -42521587200000.0; // 7/16/622 AD 00:00
28
29 // Debugging
30 #ifdef U_DEBUG_ISLAMCAL
31 # include <stdio.h>
32 # include <stdarg.h>
debug_islamcal_loc(const char * f,int32_t l)33 static void debug_islamcal_loc(const char *f, int32_t l)
34 {
35 fprintf(stderr, "%s:%d: ", f, l);
36 }
37
debug_islamcal_msg(const char * pat,...)38 static void debug_islamcal_msg(const char *pat, ...)
39 {
40 va_list ap;
41 va_start(ap, pat);
42 vfprintf(stderr, pat, ap);
43 fflush(stderr);
44 }
45 // must use double parens, i.e.: U_DEBUG_ISLAMCAL_MSG(("four is: %d",4));
46 #define U_DEBUG_ISLAMCAL_MSG(x) {debug_islamcal_loc(__FILE__,__LINE__);debug_islamcal_msg x;}
47 #else
48 #define U_DEBUG_ISLAMCAL_MSG(x)
49 #endif
50
51
52 // --- The cache --
53 // cache of months
54 static UMTX astroLock = 0; // pod bay door lock
55 static U_NAMESPACE_QUALIFIER CalendarCache *gMonthCache = NULL;
56 static U_NAMESPACE_QUALIFIER CalendarAstronomer *gIslamicCalendarAstro = NULL;
57
58 U_CDECL_BEGIN
calendar_islamic_cleanup(void)59 static UBool calendar_islamic_cleanup(void) {
60 if (gMonthCache) {
61 delete gMonthCache;
62 gMonthCache = NULL;
63 }
64 if (gIslamicCalendarAstro) {
65 delete gIslamicCalendarAstro;
66 gIslamicCalendarAstro = NULL;
67 }
68 umtx_destroy(&astroLock);
69 return TRUE;
70 }
71 U_CDECL_END
72
73 U_NAMESPACE_BEGIN
74
75 // Implementation of the IslamicCalendar class
76
77 //-------------------------------------------------------------------------
78 // Constructors...
79 //-------------------------------------------------------------------------
80
getType() const81 const char *IslamicCalendar::getType() const {
82 if(civil==CIVIL) {
83 return "islamic-civil";
84 } else {
85 return "islamic";
86 }
87 }
88
clone() const89 Calendar* IslamicCalendar::clone() const {
90 return new IslamicCalendar(*this);
91 }
92
IslamicCalendar(const Locale & aLocale,UErrorCode & success,ECivil beCivil)93 IslamicCalendar::IslamicCalendar(const Locale& aLocale, UErrorCode& success, ECivil beCivil)
94 : Calendar(TimeZone::createDefault(), aLocale, success),
95 civil(beCivil)
96 {
97 setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
98 }
99
IslamicCalendar(const IslamicCalendar & other)100 IslamicCalendar::IslamicCalendar(const IslamicCalendar& other) : Calendar(other), civil(other.civil) {
101 }
102
~IslamicCalendar()103 IslamicCalendar::~IslamicCalendar()
104 {
105 }
106
107 /**
108 * Determines whether this object uses the fixed-cycle Islamic civil calendar
109 * or an approximation of the religious, astronomical calendar.
110 *
111 * @param beCivil <code>true</code> to use the civil calendar,
112 * <code>false</code> to use the astronomical calendar.
113 * @draft ICU 2.4
114 */
setCivil(ECivil beCivil,UErrorCode & status)115 void IslamicCalendar::setCivil(ECivil beCivil, UErrorCode &status)
116 {
117 if (civil != beCivil) {
118 // The fields of the calendar will become invalid, because the calendar
119 // rules are different
120 UDate m = getTimeInMillis(status);
121 civil = beCivil;
122 clear();
123 setTimeInMillis(m, status);
124 }
125 }
126
127 /**
128 * Returns <code>true</code> if this object is using the fixed-cycle civil
129 * calendar, or <code>false</code> if using the religious, astronomical
130 * calendar.
131 * @draft ICU 2.4
132 */
isCivil()133 UBool IslamicCalendar::isCivil() {
134 return (civil == CIVIL);
135 }
136
137 //-------------------------------------------------------------------------
138 // Minimum / Maximum access functions
139 //-------------------------------------------------------------------------
140
141 // Note: Current IslamicCalendar implementation does not work
142 // well with negative years.
143
144 // TODO: In some cases the current ICU Islamic calendar implementation shows
145 // a month as having 31 days. Since date parsing now uses range checks based
146 // on the table below, we need to change the range for last day of month to
147 // include 31 as a workaround until the implementation is fixed.
148 static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
149 // Minimum Greatest Least Maximum
150 // Minimum Maximum
151 { 0, 0, 0, 0}, // ERA
152 { 1, 1, 5000000, 5000000}, // YEAR
153 { 0, 0, 11, 11}, // MONTH
154 { 1, 1, 50, 51}, // WEEK_OF_YEAR
155 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
156 { 1, 1, 29, 31}, // DAY_OF_MONTH - 31 to workaround for cal implementation bug, should be 30
157 { 1, 1, 354, 355}, // DAY_OF_YEAR
158 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
159 { -1, -1, 5, 5}, // DAY_OF_WEEK_IN_MONTH
160 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
161 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
162 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
163 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
164 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
165 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
166 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
167 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
168 { 1, 1, 5000000, 5000000}, // YEAR_WOY
169 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
170 { 1, 1, 5000000, 5000000}, // EXTENDED_YEAR
171 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
172 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
173 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
174 };
175
176 /**
177 * @draft ICU 2.4
178 */
handleGetLimit(UCalendarDateFields field,ELimitType limitType) const179 int32_t IslamicCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
180 return LIMITS[field][limitType];
181 }
182
183 //-------------------------------------------------------------------------
184 // Assorted calculation utilities
185 //
186
187 /**
188 * Determine whether a year is a leap year in the Islamic civil calendar
189 */
civilLeapYear(int32_t year)190 UBool IslamicCalendar::civilLeapYear(int32_t year)
191 {
192 return (14 + 11 * year) % 30 < 11;
193 }
194
195 /**
196 * Return the day # on which the given year starts. Days are counted
197 * from the Hijri epoch, origin 0.
198 */
yearStart(int32_t year)199 int32_t IslamicCalendar::yearStart(int32_t year) {
200 if (civil == CIVIL) {
201 return (year-1)*354 + ClockMath::floorDivide((3+11*year),30);
202 } else {
203 return trueMonthStart(12*(year-1));
204 }
205 }
206
207 /**
208 * Return the day # on which the given month starts. Days are counted
209 * from the Hijri epoch, origin 0.
210 *
211 * @param year The hijri year
212 * @param year The hijri month, 0-based
213 */
monthStart(int32_t year,int32_t month) const214 int32_t IslamicCalendar::monthStart(int32_t year, int32_t month) const {
215 if (civil == CIVIL) {
216 return (int32_t)uprv_ceil(29.5*month)
217 + (year-1)*354 + (int32_t)ClockMath::floorDivide((3+11*year),30);
218 } else {
219 return trueMonthStart(12*(year-1) + month);
220 }
221 }
222
223 /**
224 * Find the day number on which a particular month of the true/lunar
225 * Islamic calendar starts.
226 *
227 * @param month The month in question, origin 0 from the Hijri epoch
228 *
229 * @return The day number on which the given month starts.
230 */
trueMonthStart(int32_t month) const231 int32_t IslamicCalendar::trueMonthStart(int32_t month) const
232 {
233 UErrorCode status = U_ZERO_ERROR;
234 int32_t start = CalendarCache::get(&gMonthCache, month, status);
235
236 if (start==0) {
237 // Make a guess at when the month started, using the average length
238 UDate origin = HIJRA_MILLIS
239 + uprv_floor(month * CalendarAstronomer::SYNODIC_MONTH) * kOneDay;
240
241 // moonAge will fail due to memory allocation error
242 double age = moonAge(origin, status);
243 if (U_FAILURE(status)) {
244 goto trueMonthStartEnd;
245 }
246
247 if (age >= 0) {
248 // The month has already started
249 do {
250 origin -= kOneDay;
251 age = moonAge(origin, status);
252 if (U_FAILURE(status)) {
253 goto trueMonthStartEnd;
254 }
255 } while (age >= 0);
256 }
257 else {
258 // Preceding month has not ended yet.
259 do {
260 origin += kOneDay;
261 age = moonAge(origin, status);
262 if (U_FAILURE(status)) {
263 goto trueMonthStartEnd;
264 }
265 } while (age < 0);
266 }
267 start = (int32_t)ClockMath::floorDivide((origin - HIJRA_MILLIS), (double)kOneDay) + 1;
268 CalendarCache::put(&gMonthCache, month, start, status);
269 }
270 trueMonthStartEnd :
271 if(U_FAILURE(status)) {
272 start = 0;
273 }
274 return start;
275 }
276
277 /**
278 * Return the "age" of the moon at the given time; this is the difference
279 * in ecliptic latitude between the moon and the sun. This method simply
280 * calls CalendarAstronomer.moonAge, converts to degrees,
281 * and adjusts the result to be in the range [-180, 180].
282 *
283 * @param time The time at which the moon's age is desired,
284 * in millis since 1/1/1970.
285 */
moonAge(UDate time,UErrorCode & status)286 double IslamicCalendar::moonAge(UDate time, UErrorCode &status)
287 {
288 double age = 0;
289
290 umtx_lock(&astroLock);
291 if(gIslamicCalendarAstro == NULL) {
292 gIslamicCalendarAstro = new CalendarAstronomer();
293 if (gIslamicCalendarAstro == NULL) {
294 status = U_MEMORY_ALLOCATION_ERROR;
295 return age;
296 }
297 ucln_i18n_registerCleanup(UCLN_I18N_ISLAMIC_CALENDAR, calendar_islamic_cleanup);
298 }
299 gIslamicCalendarAstro->setTime(time);
300 age = gIslamicCalendarAstro->getMoonAge();
301 umtx_unlock(&astroLock);
302
303 // Convert to degrees and normalize...
304 age = age * 180 / CalendarAstronomer::PI;
305 if (age > 180) {
306 age = age - 360;
307 }
308
309 return age;
310 }
311
312 //----------------------------------------------------------------------
313 // Calendar framework
314 //----------------------------------------------------------------------
315
316 /**
317 * Return the length (in days) of the given month.
318 *
319 * @param year The hijri year
320 * @param year The hijri month, 0-based
321 * @draft ICU 2.4
322 */
handleGetMonthLength(int32_t extendedYear,int32_t month) const323 int32_t IslamicCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
324
325 int32_t length = 0;
326
327 if (civil == CIVIL) {
328 length = 29 + (month+1) % 2;
329 if (month == DHU_AL_HIJJAH && civilLeapYear(extendedYear)) {
330 length++;
331 }
332 } else {
333 month = 12*(extendedYear-1) + month;
334 length = trueMonthStart(month+1) - trueMonthStart(month) ;
335 }
336 return length;
337 }
338
339 /**
340 * Return the number of days in the given Islamic year
341 * @draft ICU 2.4
342 */
handleGetYearLength(int32_t extendedYear) const343 int32_t IslamicCalendar::handleGetYearLength(int32_t extendedYear) const {
344 if (civil == CIVIL) {
345 return 354 + (civilLeapYear(extendedYear) ? 1 : 0);
346 } else {
347 int32_t month = 12*(extendedYear-1);
348 return (trueMonthStart(month + 12) - trueMonthStart(month));
349 }
350 }
351
352 //-------------------------------------------------------------------------
353 // Functions for converting from field values to milliseconds....
354 //-------------------------------------------------------------------------
355
356 // Return JD of start of given month/year
357 /**
358 * @draft ICU 2.4
359 */
handleComputeMonthStart(int32_t eyear,int32_t month,UBool) const360 int32_t IslamicCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /* useMonth */) const {
361 return monthStart(eyear, month) + 1948439;
362 }
363
364 //-------------------------------------------------------------------------
365 // Functions for converting from milliseconds to field values
366 //-------------------------------------------------------------------------
367
368 /**
369 * @draft ICU 2.4
370 */
handleGetExtendedYear()371 int32_t IslamicCalendar::handleGetExtendedYear() {
372 int32_t year;
373 if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
374 year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
375 } else {
376 year = internalGet(UCAL_YEAR, 1); // Default to year 1
377 }
378 return year;
379 }
380
381 /**
382 * Override Calendar to compute several fields specific to the Islamic
383 * calendar system. These are:
384 *
385 * <ul><li>ERA
386 * <li>YEAR
387 * <li>MONTH
388 * <li>DAY_OF_MONTH
389 * <li>DAY_OF_YEAR
390 * <li>EXTENDED_YEAR</ul>
391 *
392 * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
393 * method is called. The getGregorianXxx() methods return Gregorian
394 * calendar equivalents for the given Julian day.
395 * @draft ICU 2.4
396 */
handleComputeFields(int32_t julianDay,UErrorCode & status)397 void IslamicCalendar::handleComputeFields(int32_t julianDay, UErrorCode &status) {
398 int32_t year, month, dayOfMonth, dayOfYear;
399 UDate startDate;
400 int32_t days = julianDay - 1948440;
401
402 if (civil == CIVIL) {
403 // Use the civil calendar approximation, which is just arithmetic
404 year = (int)ClockMath::floorDivide( (double)(30 * days + 10646) , 10631.0 );
405 month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5 );
406 month = month<11?month:11;
407 startDate = monthStart(year, month);
408 } else {
409 // Guess at the number of elapsed full months since the epoch
410 int32_t months = (int32_t)uprv_floor((double)days / CalendarAstronomer::SYNODIC_MONTH);
411
412 startDate = uprv_floor(months * CalendarAstronomer::SYNODIC_MONTH);
413
414 double age = moonAge(internalGetTime(), status);
415 if (U_FAILURE(status)) {
416 status = U_MEMORY_ALLOCATION_ERROR;
417 return;
418 }
419 if ( days - startDate >= 25 && age > 0) {
420 // If we're near the end of the month, assume next month and search backwards
421 months++;
422 }
423
424 // Find out the last time that the new moon was actually visible at this longitude
425 // This returns midnight the night that the moon was visible at sunset.
426 while ((startDate = trueMonthStart(months)) > days) {
427 // If it was after the date in question, back up a month and try again
428 months--;
429 }
430
431 year = months / 12 + 1;
432 month = months % 12;
433 }
434
435 dayOfMonth = (days - monthStart(year, month)) + 1;
436
437 // Now figure out the day of the year.
438 dayOfYear = (days - monthStart(year, 0) + 1);
439
440 internalSet(UCAL_ERA, 0);
441 internalSet(UCAL_YEAR, year);
442 internalSet(UCAL_EXTENDED_YEAR, year);
443 internalSet(UCAL_MONTH, month);
444 internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
445 internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
446 }
447
448 UBool
inDaylightTime(UErrorCode & status) const449 IslamicCalendar::inDaylightTime(UErrorCode& status) const
450 {
451 // copied from GregorianCalendar
452 if (U_FAILURE(status) || (&(getTimeZone()) == NULL && !getTimeZone().useDaylightTime()))
453 return FALSE;
454
455 // Force an update of the state of the Calendar.
456 ((IslamicCalendar*)this)->complete(status); // cast away const
457
458 return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
459 }
460
461 // default century
462 const UDate IslamicCalendar::fgSystemDefaultCentury = DBL_MIN;
463 const int32_t IslamicCalendar::fgSystemDefaultCenturyYear = -1;
464
465 UDate IslamicCalendar::fgSystemDefaultCenturyStart = DBL_MIN;
466 int32_t IslamicCalendar::fgSystemDefaultCenturyStartYear = -1;
467
468
haveDefaultCentury() const469 UBool IslamicCalendar::haveDefaultCentury() const
470 {
471 return TRUE;
472 }
473
defaultCenturyStart() const474 UDate IslamicCalendar::defaultCenturyStart() const
475 {
476 return internalGetDefaultCenturyStart();
477 }
478
defaultCenturyStartYear() const479 int32_t IslamicCalendar::defaultCenturyStartYear() const
480 {
481 return internalGetDefaultCenturyStartYear();
482 }
483
484 UDate
internalGetDefaultCenturyStart() const485 IslamicCalendar::internalGetDefaultCenturyStart() const
486 {
487 // lazy-evaluate systemDefaultCenturyStart
488 UBool needsUpdate;
489 UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
490
491 if (needsUpdate) {
492 initializeSystemDefaultCentury();
493 }
494
495 // use defaultCenturyStart unless it's the flag value;
496 // then use systemDefaultCenturyStart
497
498 return fgSystemDefaultCenturyStart;
499 }
500
501 int32_t
internalGetDefaultCenturyStartYear() const502 IslamicCalendar::internalGetDefaultCenturyStartYear() const
503 {
504 // lazy-evaluate systemDefaultCenturyStartYear
505 UBool needsUpdate;
506 UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
507
508 if (needsUpdate) {
509 initializeSystemDefaultCentury();
510 }
511
512 // use defaultCenturyStart unless it's the flag value;
513 // then use systemDefaultCenturyStartYear
514
515 return fgSystemDefaultCenturyStartYear;
516 }
517
518 void
initializeSystemDefaultCentury()519 IslamicCalendar::initializeSystemDefaultCentury()
520 {
521 // initialize systemDefaultCentury and systemDefaultCenturyYear based
522 // on the current time. They'll be set to 80 years before
523 // the current time.
524 UErrorCode status = U_ZERO_ERROR;
525 IslamicCalendar calendar(Locale("@calendar=islamic-civil"),status);
526 if (U_SUCCESS(status))
527 {
528 calendar.setTime(Calendar::getNow(), status);
529 calendar.add(UCAL_YEAR, -80, status);
530 UDate newStart = calendar.getTime(status);
531 int32_t newYear = calendar.get(UCAL_YEAR, status);
532 umtx_lock(NULL);
533 if (fgSystemDefaultCenturyStart == fgSystemDefaultCentury)
534 {
535 fgSystemDefaultCenturyStartYear = newYear;
536 fgSystemDefaultCenturyStart = newStart;
537 }
538 umtx_unlock(NULL);
539 }
540 // We have no recourse upon failure unless we want to propagate the failure
541 // out.
542 }
543
544 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(IslamicCalendar)
545
546 U_NAMESPACE_END
547
548 #endif
549
550