1 /*
2 ******************************************************************************
3 * Copyright (C) 2003-2010, 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 static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
145 // Minimum Greatest Least Maximum
146 // Minimum Maximum
147 { 0, 0, 0, 0}, // ERA
148 { 1, 1, 5000000, 5000000}, // YEAR
149 { 0, 0, 11, 11}, // MONTH
150 { 1, 1, 50, 51}, // WEEK_OF_YEAR
151 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
152 { 1, 1, 29, 30}, // DAY_OF_MONTH
153 { 1, 1, 354, 355}, // DAY_OF_YEAR
154 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
155 { -1, -1, 5, 5}, // DAY_OF_WEEK_IN_MONTH
156 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
157 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
158 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
159 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
160 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
161 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
162 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
163 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
164 { 1, 1, 5000000, 5000000}, // YEAR_WOY
165 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
166 { 1, 1, 5000000, 5000000}, // EXTENDED_YEAR
167 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
168 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
169 {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
170 };
171
172 /**
173 * @draft ICU 2.4
174 */
handleGetLimit(UCalendarDateFields field,ELimitType limitType) const175 int32_t IslamicCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
176 return LIMITS[field][limitType];
177 }
178
179 //-------------------------------------------------------------------------
180 // Assorted calculation utilities
181 //
182
183 /**
184 * Determine whether a year is a leap year in the Islamic civil calendar
185 */
civilLeapYear(int32_t year)186 UBool IslamicCalendar::civilLeapYear(int32_t year)
187 {
188 return (14 + 11 * year) % 30 < 11;
189 }
190
191 /**
192 * Return the day # on which the given year starts. Days are counted
193 * from the Hijri epoch, origin 0.
194 */
yearStart(int32_t year)195 int32_t IslamicCalendar::yearStart(int32_t year) {
196 if (civil == CIVIL) {
197 return (year-1)*354 + ClockMath::floorDivide((3+11*year),30);
198 } else {
199 return trueMonthStart(12*(year-1));
200 }
201 }
202
203 /**
204 * Return the day # on which the given month starts. Days are counted
205 * from the Hijri epoch, origin 0.
206 *
207 * @param year The hijri year
208 * @param year The hijri month, 0-based
209 */
monthStart(int32_t year,int32_t month) const210 int32_t IslamicCalendar::monthStart(int32_t year, int32_t month) const {
211 if (civil == CIVIL) {
212 return (int32_t)uprv_ceil(29.5*month)
213 + (year-1)*354 + (int32_t)ClockMath::floorDivide((3+11*year),30);
214 } else {
215 return trueMonthStart(12*(year-1) + month);
216 }
217 }
218
219 /**
220 * Find the day number on which a particular month of the true/lunar
221 * Islamic calendar starts.
222 *
223 * @param month The month in question, origin 0 from the Hijri epoch
224 *
225 * @return The day number on which the given month starts.
226 */
trueMonthStart(int32_t month) const227 int32_t IslamicCalendar::trueMonthStart(int32_t month) const
228 {
229 UErrorCode status = U_ZERO_ERROR;
230 int32_t start = CalendarCache::get(&gMonthCache, month, status);
231
232 if (start==0) {
233 // Make a guess at when the month started, using the average length
234 UDate origin = HIJRA_MILLIS
235 + uprv_floor(month * CalendarAstronomer::SYNODIC_MONTH) * kOneDay;
236
237 // moonAge will fail due to memory allocation error
238 double age = moonAge(origin, status);
239 if (U_FAILURE(status)) {
240 goto trueMonthStartEnd;
241 }
242
243 if (age >= 0) {
244 // The month has already started
245 do {
246 origin -= kOneDay;
247 age = moonAge(origin, status);
248 if (U_FAILURE(status)) {
249 goto trueMonthStartEnd;
250 }
251 } while (age >= 0);
252 }
253 else {
254 // Preceding month has not ended yet.
255 do {
256 origin += kOneDay;
257 age = moonAge(origin, status);
258 if (U_FAILURE(status)) {
259 goto trueMonthStartEnd;
260 }
261 } while (age < 0);
262 }
263 start = (int32_t)ClockMath::floorDivide((origin - HIJRA_MILLIS), (double)kOneDay) + 1;
264 CalendarCache::put(&gMonthCache, month, start, status);
265 }
266 trueMonthStartEnd :
267 if(U_FAILURE(status)) {
268 start = 0;
269 }
270 return start;
271 }
272
273 /**
274 * Return the "age" of the moon at the given time; this is the difference
275 * in ecliptic latitude between the moon and the sun. This method simply
276 * calls CalendarAstronomer.moonAge, converts to degrees,
277 * and adjusts the result to be in the range [-180, 180].
278 *
279 * @param time The time at which the moon's age is desired,
280 * in millis since 1/1/1970.
281 */
moonAge(UDate time,UErrorCode & status)282 double IslamicCalendar::moonAge(UDate time, UErrorCode &status)
283 {
284 double age = 0;
285
286 umtx_lock(&astroLock);
287 if(gIslamicCalendarAstro == NULL) {
288 gIslamicCalendarAstro = new CalendarAstronomer();
289 if (gIslamicCalendarAstro == NULL) {
290 status = U_MEMORY_ALLOCATION_ERROR;
291 return age;
292 }
293 ucln_i18n_registerCleanup(UCLN_I18N_ISLAMIC_CALENDAR, calendar_islamic_cleanup);
294 }
295 gIslamicCalendarAstro->setTime(time);
296 age = gIslamicCalendarAstro->getMoonAge();
297 umtx_unlock(&astroLock);
298
299 // Convert to degrees and normalize...
300 age = age * 180 / CalendarAstronomer::PI;
301 if (age > 180) {
302 age = age - 360;
303 }
304
305 return age;
306 }
307
308 //----------------------------------------------------------------------
309 // Calendar framework
310 //----------------------------------------------------------------------
311
312 /**
313 * Return the length (in days) of the given month.
314 *
315 * @param year The hijri year
316 * @param year The hijri month, 0-based
317 * @draft ICU 2.4
318 */
handleGetMonthLength(int32_t extendedYear,int32_t month) const319 int32_t IslamicCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
320
321 int32_t length = 0;
322
323 if (civil == CIVIL) {
324 length = 29 + (month+1) % 2;
325 if (month == DHU_AL_HIJJAH && civilLeapYear(extendedYear)) {
326 length++;
327 }
328 } else {
329 month = 12*(extendedYear-1) + month;
330 length = trueMonthStart(month+1) - trueMonthStart(month) ;
331 }
332 return length;
333 }
334
335 /**
336 * Return the number of days in the given Islamic year
337 * @draft ICU 2.4
338 */
handleGetYearLength(int32_t extendedYear) const339 int32_t IslamicCalendar::handleGetYearLength(int32_t extendedYear) const {
340 if (civil == CIVIL) {
341 return 354 + (civilLeapYear(extendedYear) ? 1 : 0);
342 } else {
343 int32_t month = 12*(extendedYear-1);
344 return (trueMonthStart(month + 12) - trueMonthStart(month));
345 }
346 }
347
348 //-------------------------------------------------------------------------
349 // Functions for converting from field values to milliseconds....
350 //-------------------------------------------------------------------------
351
352 // Return JD of start of given month/year
353 /**
354 * @draft ICU 2.4
355 */
handleComputeMonthStart(int32_t eyear,int32_t month,UBool) const356 int32_t IslamicCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /* useMonth */) const {
357 return monthStart(eyear, month) + 1948439;
358 }
359
360 //-------------------------------------------------------------------------
361 // Functions for converting from milliseconds to field values
362 //-------------------------------------------------------------------------
363
364 /**
365 * @draft ICU 2.4
366 */
handleGetExtendedYear()367 int32_t IslamicCalendar::handleGetExtendedYear() {
368 int32_t year;
369 if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
370 year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
371 } else {
372 year = internalGet(UCAL_YEAR, 1); // Default to year 1
373 }
374 return year;
375 }
376
377 /**
378 * Override Calendar to compute several fields specific to the Islamic
379 * calendar system. These are:
380 *
381 * <ul><li>ERA
382 * <li>YEAR
383 * <li>MONTH
384 * <li>DAY_OF_MONTH
385 * <li>DAY_OF_YEAR
386 * <li>EXTENDED_YEAR</ul>
387 *
388 * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
389 * method is called. The getGregorianXxx() methods return Gregorian
390 * calendar equivalents for the given Julian day.
391 * @draft ICU 2.4
392 */
handleComputeFields(int32_t julianDay,UErrorCode & status)393 void IslamicCalendar::handleComputeFields(int32_t julianDay, UErrorCode &status) {
394 int32_t year, month, dayOfMonth, dayOfYear;
395 UDate startDate;
396 int32_t days = julianDay - 1948440;
397
398 if (civil == CIVIL) {
399 // Use the civil calendar approximation, which is just arithmetic
400 year = (int)ClockMath::floorDivide( (double)(30 * days + 10646) , 10631.0 );
401 month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5 );
402 month = month<11?month:11;
403 startDate = monthStart(year, month);
404 } else {
405 // Guess at the number of elapsed full months since the epoch
406 int32_t months = (int32_t)uprv_floor((double)days / CalendarAstronomer::SYNODIC_MONTH);
407
408 startDate = uprv_floor(months * CalendarAstronomer::SYNODIC_MONTH);
409
410 double age = moonAge(internalGetTime(), status);
411 if (U_FAILURE(status)) {
412 status = U_MEMORY_ALLOCATION_ERROR;
413 return;
414 }
415 if ( days - startDate >= 25 && age > 0) {
416 // If we're near the end of the month, assume next month and search backwards
417 months++;
418 }
419
420 // Find out the last time that the new moon was actually visible at this longitude
421 // This returns midnight the night that the moon was visible at sunset.
422 while ((startDate = trueMonthStart(months)) > days) {
423 // If it was after the date in question, back up a month and try again
424 months--;
425 }
426
427 year = months / 12 + 1;
428 month = months % 12;
429 }
430
431 dayOfMonth = (days - monthStart(year, month)) + 1;
432
433 // Now figure out the day of the year.
434 dayOfYear = (days - monthStart(year, 0) + 1);
435
436 internalSet(UCAL_ERA, 0);
437 internalSet(UCAL_YEAR, year);
438 internalSet(UCAL_EXTENDED_YEAR, year);
439 internalSet(UCAL_MONTH, month);
440 internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
441 internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
442 }
443
444 UBool
inDaylightTime(UErrorCode & status) const445 IslamicCalendar::inDaylightTime(UErrorCode& status) const
446 {
447 // copied from GregorianCalendar
448 if (U_FAILURE(status) || (&(getTimeZone()) == NULL && !getTimeZone().useDaylightTime()))
449 return FALSE;
450
451 // Force an update of the state of the Calendar.
452 ((IslamicCalendar*)this)->complete(status); // cast away const
453
454 return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
455 }
456
457 // default century
458 const UDate IslamicCalendar::fgSystemDefaultCentury = DBL_MIN;
459 const int32_t IslamicCalendar::fgSystemDefaultCenturyYear = -1;
460
461 UDate IslamicCalendar::fgSystemDefaultCenturyStart = DBL_MIN;
462 int32_t IslamicCalendar::fgSystemDefaultCenturyStartYear = -1;
463
464
haveDefaultCentury() const465 UBool IslamicCalendar::haveDefaultCentury() const
466 {
467 return TRUE;
468 }
469
defaultCenturyStart() const470 UDate IslamicCalendar::defaultCenturyStart() const
471 {
472 return internalGetDefaultCenturyStart();
473 }
474
defaultCenturyStartYear() const475 int32_t IslamicCalendar::defaultCenturyStartYear() const
476 {
477 return internalGetDefaultCenturyStartYear();
478 }
479
480 UDate
internalGetDefaultCenturyStart() const481 IslamicCalendar::internalGetDefaultCenturyStart() const
482 {
483 // lazy-evaluate systemDefaultCenturyStart
484 UBool needsUpdate;
485 UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
486
487 if (needsUpdate) {
488 initializeSystemDefaultCentury();
489 }
490
491 // use defaultCenturyStart unless it's the flag value;
492 // then use systemDefaultCenturyStart
493
494 return fgSystemDefaultCenturyStart;
495 }
496
497 int32_t
internalGetDefaultCenturyStartYear() const498 IslamicCalendar::internalGetDefaultCenturyStartYear() const
499 {
500 // lazy-evaluate systemDefaultCenturyStartYear
501 UBool needsUpdate;
502 UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
503
504 if (needsUpdate) {
505 initializeSystemDefaultCentury();
506 }
507
508 // use defaultCenturyStart unless it's the flag value;
509 // then use systemDefaultCenturyStartYear
510
511 return fgSystemDefaultCenturyStartYear;
512 }
513
514 void
initializeSystemDefaultCentury()515 IslamicCalendar::initializeSystemDefaultCentury()
516 {
517 // initialize systemDefaultCentury and systemDefaultCenturyYear based
518 // on the current time. They'll be set to 80 years before
519 // the current time.
520 UErrorCode status = U_ZERO_ERROR;
521 IslamicCalendar calendar(Locale("@calendar=islamic-civil"),status);
522 if (U_SUCCESS(status))
523 {
524 calendar.setTime(Calendar::getNow(), status);
525 calendar.add(UCAL_YEAR, -80, status);
526 UDate newStart = calendar.getTime(status);
527 int32_t newYear = calendar.get(UCAL_YEAR, status);
528 umtx_lock(NULL);
529 if (fgSystemDefaultCenturyStart == fgSystemDefaultCentury)
530 {
531 fgSystemDefaultCenturyStartYear = newYear;
532 fgSystemDefaultCenturyStart = newStart;
533 }
534 umtx_unlock(NULL);
535 }
536 // We have no recourse upon failure unless we want to propagate the failure
537 // out.
538 }
539
540 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(IslamicCalendar)
541
542 U_NAMESPACE_END
543
544 #endif
545
546