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Diffstat (limited to 'intl/icu/source/i18n/gregocal.cpp')
| -rw-r--r-- | intl/icu/source/i18n/gregocal.cpp | 1320 |
1 files changed, 1320 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/gregocal.cpp b/intl/icu/source/i18n/gregocal.cpp new file mode 100644 index 000000000..11082223c --- /dev/null +++ b/intl/icu/source/i18n/gregocal.cpp @@ -0,0 +1,1320 @@ +// Copyright (C) 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +******************************************************************************* +* Copyright (C) 1997-2016, International Business Machines Corporation and +* others. All Rights Reserved. +******************************************************************************* +* +* File GREGOCAL.CPP +* +* Modification History: +* +* Date Name Description +* 02/05/97 clhuang Creation. +* 03/28/97 aliu Made highly questionable fix to computeFields to +* handle DST correctly. +* 04/22/97 aliu Cleaned up code drastically. Added monthLength(). +* Finished unimplemented parts of computeTime() for +* week-based date determination. Removed quetionable +* fix and wrote correct fix for computeFields() and +* daylight time handling. Rewrote inDaylightTime() +* and computeFields() to handle sensitive Daylight to +* Standard time transitions correctly. +* 05/08/97 aliu Added code review changes. Fixed isLeapYear() to +* not cutover. +* 08/12/97 aliu Added equivalentTo. Misc other fixes. Updated +* add() from Java source. +* 07/28/98 stephen Sync up with JDK 1.2 +* 09/14/98 stephen Changed type of kOneDay, kOneWeek to double. +* Fixed bug in roll() +* 10/15/99 aliu Fixed j31, incorrect WEEK_OF_YEAR computation. +* 10/15/99 aliu Fixed j32, cannot set date to Feb 29 2000 AD. +* {JDK bug 4210209 4209272} +* 11/15/99 weiv Added YEAR_WOY and DOW_LOCAL computation +* to timeToFields method, updated kMinValues, kMaxValues & kLeastMaxValues +* 12/09/99 aliu Fixed j81, calculation errors and roll bugs +* in year of cutover. +* 01/24/2000 aliu Revised computeJulianDay for YEAR YEAR_WOY WOY. +******************************************************************************** +*/ + +#include "unicode/utypes.h" +#include <float.h> + +#if !UCONFIG_NO_FORMATTING + +#include "unicode/gregocal.h" +#include "gregoimp.h" +#include "umutex.h" +#include "uassert.h" + +// ***************************************************************************** +// class GregorianCalendar +// ***************************************************************************** + +/** +* Note that the Julian date used here is not a true Julian date, since +* it is measured from midnight, not noon. This value is the Julian +* day number of January 1, 1970 (Gregorian calendar) at noon UTC. [LIU] +*/ + +static const int16_t kNumDays[] += {0,31,59,90,120,151,181,212,243,273,304,334}; // 0-based, for day-in-year +static const int16_t kLeapNumDays[] += {0,31,60,91,121,152,182,213,244,274,305,335}; // 0-based, for day-in-year +static const int8_t kMonthLength[] += {31,28,31,30,31,30,31,31,30,31,30,31}; // 0-based +static const int8_t kLeapMonthLength[] += {31,29,31,30,31,30,31,31,30,31,30,31}; // 0-based + +// setTimeInMillis() limits the Julian day range to +/-7F000000. +// This would seem to limit the year range to: +// ms=+183882168921600000 jd=7f000000 December 20, 5828963 AD +// ms=-184303902528000000 jd=81000000 September 20, 5838270 BC +// HOWEVER, CalendarRegressionTest/Test4167060 shows that the actual +// range limit on the year field is smaller (~ +/-140000). [alan 3.0] + +static const int32_t kGregorianCalendarLimits[UCAL_FIELD_COUNT][4] = { + // Minimum Greatest Least Maximum + // Minimum Maximum + { 0, 0, 1, 1}, // ERA + { 1, 1, 140742, 144683}, // YEAR + { 0, 0, 11, 11}, // MONTH + { 1, 1, 52, 53}, // WEEK_OF_YEAR + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH + { 1, 1, 28, 31}, // DAY_OF_MONTH + { 1, 1, 365, 366}, // DAY_OF_YEAR + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK + { -1, -1, 4, 5}, // DAY_OF_WEEK_IN_MONTH + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET + { -140742, -140742, 140742, 144683}, // YEAR_WOY + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL + { -140742, -140742, 140742, 144683}, // EXTENDED_YEAR + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY + {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH +}; + +/* +* <pre> +* Greatest Least +* Field name Minimum Minimum Maximum Maximum +* ---------- ------- ------- ------- ------- +* ERA 0 0 1 1 +* YEAR 1 1 140742 144683 +* MONTH 0 0 11 11 +* WEEK_OF_YEAR 1 1 52 53 +* WEEK_OF_MONTH 0 0 4 6 +* DAY_OF_MONTH 1 1 28 31 +* DAY_OF_YEAR 1 1 365 366 +* DAY_OF_WEEK 1 1 7 7 +* DAY_OF_WEEK_IN_MONTH -1 -1 4 5 +* AM_PM 0 0 1 1 +* HOUR 0 0 11 11 +* HOUR_OF_DAY 0 0 23 23 +* MINUTE 0 0 59 59 +* SECOND 0 0 59 59 +* MILLISECOND 0 0 999 999 +* ZONE_OFFSET -12* -12* 12* 12* +* DST_OFFSET 0 0 1* 1* +* YEAR_WOY 1 1 140742 144683 +* DOW_LOCAL 1 1 7 7 +* </pre> +* (*) In units of one-hour +*/ + +#if defined( U_DEBUG_CALSVC ) || defined (U_DEBUG_CAL) +#include <stdio.h> +#endif + +U_NAMESPACE_BEGIN + +UOBJECT_DEFINE_RTTI_IMPLEMENTATION(GregorianCalendar) + +// 00:00:00 UTC, October 15, 1582, expressed in ms from the epoch. +// Note that only Italy and other Catholic countries actually +// observed this cutover. Most other countries followed in +// the next few centuries, some as late as 1928. [LIU] +// in Java, -12219292800000L +//const UDate GregorianCalendar::kPapalCutover = -12219292800000L; +static const uint32_t kCutoverJulianDay = 2299161; +static const UDate kPapalCutover = (2299161.0 - kEpochStartAsJulianDay) * U_MILLIS_PER_DAY; +//static const UDate kPapalCutoverJulian = (2299161.0 - kEpochStartAsJulianDay); + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(UErrorCode& status) +: Calendar(status), +fGregorianCutover(kPapalCutover), +fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), +fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + setTimeInMillis(getNow(), status); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(TimeZone* zone, UErrorCode& status) +: Calendar(zone, Locale::getDefault(), status), +fGregorianCutover(kPapalCutover), +fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), +fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + setTimeInMillis(getNow(), status); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(const TimeZone& zone, UErrorCode& status) +: Calendar(zone, Locale::getDefault(), status), +fGregorianCutover(kPapalCutover), +fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), +fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + setTimeInMillis(getNow(), status); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(const Locale& aLocale, UErrorCode& status) +: Calendar(TimeZone::createDefault(), aLocale, status), +fGregorianCutover(kPapalCutover), +fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), +fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + setTimeInMillis(getNow(), status); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(TimeZone* zone, const Locale& aLocale, + UErrorCode& status) + : Calendar(zone, aLocale, status), + fGregorianCutover(kPapalCutover), + fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), + fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + setTimeInMillis(getNow(), status); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(const TimeZone& zone, const Locale& aLocale, + UErrorCode& status) + : Calendar(zone, aLocale, status), + fGregorianCutover(kPapalCutover), + fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), + fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + setTimeInMillis(getNow(), status); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date, + UErrorCode& status) + : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), + fGregorianCutover(kPapalCutover), + fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), + fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + set(UCAL_ERA, AD); + set(UCAL_YEAR, year); + set(UCAL_MONTH, month); + set(UCAL_DATE, date); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date, + int32_t hour, int32_t minute, UErrorCode& status) + : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), + fGregorianCutover(kPapalCutover), + fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), + fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + set(UCAL_ERA, AD); + set(UCAL_YEAR, year); + set(UCAL_MONTH, month); + set(UCAL_DATE, date); + set(UCAL_HOUR_OF_DAY, hour); + set(UCAL_MINUTE, minute); +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date, + int32_t hour, int32_t minute, int32_t second, + UErrorCode& status) + : Calendar(TimeZone::createDefault(), Locale::getDefault(), status), + fGregorianCutover(kPapalCutover), + fCutoverJulianDay(kCutoverJulianDay), fNormalizedGregorianCutover(fGregorianCutover), fGregorianCutoverYear(1582), + fIsGregorian(TRUE), fInvertGregorian(FALSE) +{ + set(UCAL_ERA, AD); + set(UCAL_YEAR, year); + set(UCAL_MONTH, month); + set(UCAL_DATE, date); + set(UCAL_HOUR_OF_DAY, hour); + set(UCAL_MINUTE, minute); + set(UCAL_SECOND, second); +} + +// ------------------------------------- + +GregorianCalendar::~GregorianCalendar() +{ +} + +// ------------------------------------- + +GregorianCalendar::GregorianCalendar(const GregorianCalendar &source) +: Calendar(source), +fGregorianCutover(source.fGregorianCutover), +fCutoverJulianDay(source.fCutoverJulianDay), fNormalizedGregorianCutover(source.fNormalizedGregorianCutover), fGregorianCutoverYear(source.fGregorianCutoverYear), +fIsGregorian(source.fIsGregorian), fInvertGregorian(source.fInvertGregorian) +{ +} + +// ------------------------------------- + +Calendar* GregorianCalendar::clone() const +{ + return new GregorianCalendar(*this); +} + +// ------------------------------------- + +GregorianCalendar & +GregorianCalendar::operator=(const GregorianCalendar &right) +{ + if (this != &right) + { + Calendar::operator=(right); + fGregorianCutover = right.fGregorianCutover; + fNormalizedGregorianCutover = right.fNormalizedGregorianCutover; + fGregorianCutoverYear = right.fGregorianCutoverYear; + fCutoverJulianDay = right.fCutoverJulianDay; + } + return *this; +} + +// ------------------------------------- + +UBool GregorianCalendar::isEquivalentTo(const Calendar& other) const +{ + // Calendar override. + return Calendar::isEquivalentTo(other) && + fGregorianCutover == ((GregorianCalendar*)&other)->fGregorianCutover; +} + +// ------------------------------------- + +void +GregorianCalendar::setGregorianChange(UDate date, UErrorCode& status) +{ + if (U_FAILURE(status)) + return; + + fGregorianCutover = date; + + // Precompute two internal variables which we use to do the actual + // cutover computations. These are the normalized cutover, which is the + // midnight at or before the cutover, and the cutover year. The + // normalized cutover is in pure date milliseconds; it contains no time + // of day or timezone component, and it used to compare against other + // pure date values. + int32_t cutoverDay = (int32_t)ClockMath::floorDivide(fGregorianCutover, (double)kOneDay); + fNormalizedGregorianCutover = cutoverDay * kOneDay; + + // Handle the rare case of numeric overflow. If the user specifies a + // change of UDate(Long.MIN_VALUE), in order to get a pure Gregorian + // calendar, then the epoch day is -106751991168, which when multiplied + // by ONE_DAY gives 9223372036794351616 -- the negative value is too + // large for 64 bits, and overflows into a positive value. We correct + // this by using the next day, which for all intents is semantically + // equivalent. + if (cutoverDay < 0 && fNormalizedGregorianCutover > 0) { + fNormalizedGregorianCutover = (cutoverDay + 1) * kOneDay; + } + + // Normalize the year so BC values are represented as 0 and negative + // values. + GregorianCalendar *cal = new GregorianCalendar(getTimeZone(), status); + /* test for NULL */ + if (cal == 0) { + status = U_MEMORY_ALLOCATION_ERROR; + return; + } + if(U_FAILURE(status)) + return; + cal->setTime(date, status); + fGregorianCutoverYear = cal->get(UCAL_YEAR, status); + if (cal->get(UCAL_ERA, status) == BC) + fGregorianCutoverYear = 1 - fGregorianCutoverYear; + fCutoverJulianDay = cutoverDay; + delete cal; +} + + +void GregorianCalendar::handleComputeFields(int32_t julianDay, UErrorCode& status) { + int32_t eyear, month, dayOfMonth, dayOfYear, unusedRemainder; + + + if(U_FAILURE(status)) { + return; + } + +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: jd%d- (greg's %d)- [cut=%d]\n", + __FILE__, __LINE__, julianDay, getGregorianDayOfYear(), fCutoverJulianDay); +#endif + + + if (julianDay >= fCutoverJulianDay) { + month = getGregorianMonth(); + dayOfMonth = getGregorianDayOfMonth(); + dayOfYear = getGregorianDayOfYear(); + eyear = getGregorianYear(); + } else { + // The Julian epoch day (not the same as Julian Day) + // is zero on Saturday December 30, 0 (Gregorian). + int32_t julianEpochDay = julianDay - (kJan1_1JulianDay - 2); + eyear = (int32_t) ClockMath::floorDivide((4.0*julianEpochDay) + 1464.0, (int32_t) 1461, unusedRemainder); + + // Compute the Julian calendar day number for January 1, eyear + int32_t january1 = 365*(eyear-1) + ClockMath::floorDivide(eyear-1, (int32_t)4); + dayOfYear = (julianEpochDay - january1); // 0-based + + // Julian leap years occurred historically every 4 years starting + // with 8 AD. Before 8 AD the spacing is irregular; every 3 years + // from 45 BC to 9 BC, and then none until 8 AD. However, we don't + // implement this historical detail; instead, we implement the + // computatinally cleaner proleptic calendar, which assumes + // consistent 4-year cycles throughout time. + UBool isLeap = ((eyear&0x3) == 0); // equiv. to (eyear%4 == 0) + + // Common Julian/Gregorian calculation + int32_t correction = 0; + int32_t march1 = isLeap ? 60 : 59; // zero-based DOY for March 1 + if (dayOfYear >= march1) { + correction = isLeap ? 1 : 2; + } + month = (12 * (dayOfYear + correction) + 6) / 367; // zero-based month + dayOfMonth = dayOfYear - (isLeap?kLeapNumDays[month]:kNumDays[month]) + 1; // one-based DOM + ++dayOfYear; +#if defined (U_DEBUG_CAL) + // fprintf(stderr, "%d - %d[%d] + 1\n", dayOfYear, isLeap?kLeapNumDays[month]:kNumDays[month], month ); + // fprintf(stderr, "%s:%d: greg's HCF %d -> %d/%d/%d not %d/%d/%d\n", + // __FILE__, __LINE__,julianDay, + // eyear,month,dayOfMonth, + // getGregorianYear(), getGregorianMonth(), getGregorianDayOfMonth() ); + fprintf(stderr, "%s:%d: doy %d (greg's %d)- [cut=%d]\n", + __FILE__, __LINE__, dayOfYear, getGregorianDayOfYear(), fCutoverJulianDay); +#endif + + } + + // [j81] if we are after the cutover in its year, shift the day of the year + if((eyear == fGregorianCutoverYear) && (julianDay >= fCutoverJulianDay)) { + //from handleComputeMonthStart + int32_t gregShift = Grego::gregorianShift(eyear); +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: gregorian shift %d ::: doy%d => %d [cut=%d]\n", + __FILE__, __LINE__,gregShift, dayOfYear, dayOfYear+gregShift, fCutoverJulianDay); +#endif + dayOfYear += gregShift; + } + + internalSet(UCAL_MONTH, month); + internalSet(UCAL_DAY_OF_MONTH, dayOfMonth); + internalSet(UCAL_DAY_OF_YEAR, dayOfYear); + internalSet(UCAL_EXTENDED_YEAR, eyear); + int32_t era = AD; + if (eyear < 1) { + era = BC; + eyear = 1 - eyear; + } + internalSet(UCAL_ERA, era); + internalSet(UCAL_YEAR, eyear); +} + + +// ------------------------------------- + +UDate +GregorianCalendar::getGregorianChange() const +{ + return fGregorianCutover; +} + +// ------------------------------------- + +UBool +GregorianCalendar::isLeapYear(int32_t year) const +{ + // MSVC complains bitterly if we try to use Grego::isLeapYear here + // NOTE: year&0x3 == year%4 + return (year >= fGregorianCutoverYear ? + (((year&0x3) == 0) && ((year%100 != 0) || (year%400 == 0))) : // Gregorian + ((year&0x3) == 0)); // Julian +} + +// ------------------------------------- + +int32_t GregorianCalendar::handleComputeJulianDay(UCalendarDateFields bestField) +{ + fInvertGregorian = FALSE; + + int32_t jd = Calendar::handleComputeJulianDay(bestField); + + if((bestField == UCAL_WEEK_OF_YEAR) && // if we are doing WOY calculations, we are counting relative to Jan 1 *julian* + (internalGet(UCAL_EXTENDED_YEAR)==fGregorianCutoverYear) && + jd >= fCutoverJulianDay) { + fInvertGregorian = TRUE; // So that the Julian Jan 1 will be used in handleComputeMonthStart + return Calendar::handleComputeJulianDay(bestField); + } + + + // The following check handles portions of the cutover year BEFORE the + // cutover itself happens. + //if ((fIsGregorian==TRUE) != (jd >= fCutoverJulianDay)) { /* cutoverJulianDay)) { */ + if ((fIsGregorian==TRUE) != (jd >= fCutoverJulianDay)) { /* cutoverJulianDay)) { */ +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: jd [invert] %d\n", + __FILE__, __LINE__, jd); +#endif + fInvertGregorian = TRUE; + jd = Calendar::handleComputeJulianDay(bestField); +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: fIsGregorian %s, fInvertGregorian %s - ", + __FILE__, __LINE__,fIsGregorian?"T":"F", fInvertGregorian?"T":"F"); + fprintf(stderr, " jd NOW %d\n", + jd); +#endif + } else { +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: jd [==] %d - %sfIsGregorian %sfInvertGregorian, %d\n", + __FILE__, __LINE__, jd, fIsGregorian?"T":"F", fInvertGregorian?"T":"F", bestField); +#endif + } + + if(fIsGregorian && (internalGet(UCAL_EXTENDED_YEAR) == fGregorianCutoverYear)) { + int32_t gregShift = Grego::gregorianShift(internalGet(UCAL_EXTENDED_YEAR)); + if (bestField == UCAL_DAY_OF_YEAR) { +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: [DOY%d] gregorian shift of JD %d += %d\n", + __FILE__, __LINE__, fFields[bestField],jd, gregShift); +#endif + jd -= gregShift; + } else if ( bestField == UCAL_WEEK_OF_MONTH ) { + int32_t weekShift = 14; +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: [WOY/WOM] gregorian week shift of %d += %d\n", + __FILE__, __LINE__, jd, weekShift); +#endif + jd += weekShift; // shift by weeks for week based fields. + } + } + + return jd; +} + +int32_t GregorianCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, + + UBool /* useMonth */) const +{ + GregorianCalendar *nonConstThis = (GregorianCalendar*)this; // cast away const + + // If the month is out of range, adjust it into range, and + // modify the extended year value accordingly. + if (month < 0 || month > 11) { + eyear += ClockMath::floorDivide(month, 12, month); + } + + UBool isLeap = eyear%4 == 0; + int32_t y = eyear-1; + int32_t julianDay = 365*y + ClockMath::floorDivide(y, 4) + (kJan1_1JulianDay - 3); + + nonConstThis->fIsGregorian = (eyear >= fGregorianCutoverYear); +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: (hcms%d/%d) fIsGregorian %s, fInvertGregorian %s\n", + __FILE__, __LINE__, eyear,month, fIsGregorian?"T":"F", fInvertGregorian?"T":"F"); +#endif + if (fInvertGregorian) { + nonConstThis->fIsGregorian = !fIsGregorian; + } + if (fIsGregorian) { + isLeap = isLeap && ((eyear%100 != 0) || (eyear%400 == 0)); + // Add 2 because Gregorian calendar starts 2 days after + // Julian calendar + int32_t gregShift = Grego::gregorianShift(eyear); +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: (hcms%d/%d) gregorian shift of %d += %d\n", + __FILE__, __LINE__, eyear, month, julianDay, gregShift); +#endif + julianDay += gregShift; + } + + // At this point julianDay indicates the day BEFORE the first + // day of January 1, <eyear> of either the Julian or Gregorian + // calendar. + + if (month != 0) { + julianDay += isLeap?kLeapNumDays[month]:kNumDays[month]; + } + + return julianDay; +} + +int32_t GregorianCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const +{ + // If the month is out of range, adjust it into range, and + // modify the extended year value accordingly. + if (month < 0 || month > 11) { + extendedYear += ClockMath::floorDivide(month, 12, month); + } + + return isLeapYear(extendedYear) ? kLeapMonthLength[month] : kMonthLength[month]; +} + +int32_t GregorianCalendar::handleGetYearLength(int32_t eyear) const { + return isLeapYear(eyear) ? 366 : 365; +} + + +int32_t +GregorianCalendar::monthLength(int32_t month) const +{ + int32_t year = internalGet(UCAL_EXTENDED_YEAR); + return handleGetMonthLength(year, month); +} + +// ------------------------------------- + +int32_t +GregorianCalendar::monthLength(int32_t month, int32_t year) const +{ + return isLeapYear(year) ? kLeapMonthLength[month] : kMonthLength[month]; +} + +// ------------------------------------- + +int32_t +GregorianCalendar::yearLength(int32_t year) const +{ + return isLeapYear(year) ? 366 : 365; +} + +// ------------------------------------- + +int32_t +GregorianCalendar::yearLength() const +{ + return isLeapYear(internalGet(UCAL_YEAR)) ? 366 : 365; +} + +// ------------------------------------- + +/** +* After adjustments such as add(MONTH), add(YEAR), we don't want the +* month to jump around. E.g., we don't want Jan 31 + 1 month to go to Mar +* 3, we want it to go to Feb 28. Adjustments which might run into this +* problem call this method to retain the proper month. +*/ +void +GregorianCalendar::pinDayOfMonth() +{ + int32_t monthLen = monthLength(internalGet(UCAL_MONTH)); + int32_t dom = internalGet(UCAL_DATE); + if(dom > monthLen) + set(UCAL_DATE, monthLen); +} + +// ------------------------------------- + + +UBool +GregorianCalendar::validateFields() const +{ + for (int32_t field = 0; field < UCAL_FIELD_COUNT; field++) { + // Ignore DATE and DAY_OF_YEAR which are handled below + if (field != UCAL_DATE && + field != UCAL_DAY_OF_YEAR && + isSet((UCalendarDateFields)field) && + ! boundsCheck(internalGet((UCalendarDateFields)field), (UCalendarDateFields)field)) + return FALSE; + } + + // Values differ in Least-Maximum and Maximum should be handled + // specially. + if (isSet(UCAL_DATE)) { + int32_t date = internalGet(UCAL_DATE); + if (date < getMinimum(UCAL_DATE) || + date > monthLength(internalGet(UCAL_MONTH))) { + return FALSE; + } + } + + if (isSet(UCAL_DAY_OF_YEAR)) { + int32_t days = internalGet(UCAL_DAY_OF_YEAR); + if (days < 1 || days > yearLength()) { + return FALSE; + } + } + + // Handle DAY_OF_WEEK_IN_MONTH, which must not have the value zero. + // We've checked against minimum and maximum above already. + if (isSet(UCAL_DAY_OF_WEEK_IN_MONTH) && + 0 == internalGet(UCAL_DAY_OF_WEEK_IN_MONTH)) { + return FALSE; + } + + return TRUE; +} + +// ------------------------------------- + +UBool +GregorianCalendar::boundsCheck(int32_t value, UCalendarDateFields field) const +{ + return value >= getMinimum(field) && value <= getMaximum(field); +} + +// ------------------------------------- + +UDate +GregorianCalendar::getEpochDay(UErrorCode& status) +{ + complete(status); + // Divide by 1000 (convert to seconds) in order to prevent overflow when + // dealing with UDate(Long.MIN_VALUE) and UDate(Long.MAX_VALUE). + double wallSec = internalGetTime()/1000 + (internalGet(UCAL_ZONE_OFFSET) + internalGet(UCAL_DST_OFFSET))/1000; + + return ClockMath::floorDivide(wallSec, kOneDay/1000.0); +} + +// ------------------------------------- + + +// ------------------------------------- + +/** +* Compute the julian day number of the day BEFORE the first day of +* January 1, year 1 of the given calendar. If julianDay == 0, it +* specifies (Jan. 1, 1) - 1, in whatever calendar we are using (Julian +* or Gregorian). +*/ +double GregorianCalendar::computeJulianDayOfYear(UBool isGregorian, + int32_t year, UBool& isLeap) +{ + isLeap = year%4 == 0; + int32_t y = year - 1; + double julianDay = 365.0*y + ClockMath::floorDivide(y, 4) + (kJan1_1JulianDay - 3); + + if (isGregorian) { + isLeap = isLeap && ((year%100 != 0) || (year%400 == 0)); + // Add 2 because Gregorian calendar starts 2 days after Julian calendar + julianDay += Grego::gregorianShift(year); + } + + return julianDay; +} + +// /** +// * Compute the day of week, relative to the first day of week, from +// * 0..6, of the current DOW_LOCAL or DAY_OF_WEEK fields. This is +// * equivalent to get(DOW_LOCAL) - 1. +// */ +// int32_t GregorianCalendar::computeRelativeDOW() const { +// int32_t relDow = 0; +// if (fStamp[UCAL_DOW_LOCAL] > fStamp[UCAL_DAY_OF_WEEK]) { +// relDow = internalGet(UCAL_DOW_LOCAL) - 1; // 1-based +// } else if (fStamp[UCAL_DAY_OF_WEEK] != kUnset) { +// relDow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek(); +// if (relDow < 0) relDow += 7; +// } +// return relDow; +// } + +// /** +// * Compute the day of week, relative to the first day of week, +// * from 0..6 of the given julian day. +// */ +// int32_t GregorianCalendar::computeRelativeDOW(double julianDay) const { +// int32_t relDow = julianDayToDayOfWeek(julianDay) - getFirstDayOfWeek(); +// if (relDow < 0) { +// relDow += 7; +// } +// return relDow; +// } + +// /** +// * Compute the DOY using the WEEK_OF_YEAR field and the julian day +// * of the day BEFORE January 1 of a year (a return value from +// * computeJulianDayOfYear). +// */ +// int32_t GregorianCalendar::computeDOYfromWOY(double julianDayOfYear) const { +// // Compute DOY from day of week plus week of year + +// // Find the day of the week for the first of this year. This +// // is zero-based, with 0 being the locale-specific first day of +// // the week. Add 1 to get first day of year. +// int32_t fdy = computeRelativeDOW(julianDayOfYear + 1); + +// return +// // Compute doy of first (relative) DOW of WOY 1 +// (((7 - fdy) < getMinimalDaysInFirstWeek()) +// ? (8 - fdy) : (1 - fdy)) + +// // Adjust for the week number. +// + (7 * (internalGet(UCAL_WEEK_OF_YEAR) - 1)) + +// // Adjust for the DOW +// + computeRelativeDOW(); +// } + +// ------------------------------------- + +double +GregorianCalendar::millisToJulianDay(UDate millis) +{ + return (double)kEpochStartAsJulianDay + ClockMath::floorDivide(millis, (double)kOneDay); +} + +// ------------------------------------- + +UDate +GregorianCalendar::julianDayToMillis(double julian) +{ + return (UDate) ((julian - kEpochStartAsJulianDay) * (double) kOneDay); +} + +// ------------------------------------- + +int32_t +GregorianCalendar::aggregateStamp(int32_t stamp_a, int32_t stamp_b) +{ + return (((stamp_a != kUnset && stamp_b != kUnset) + ? uprv_max(stamp_a, stamp_b) + : (int32_t)kUnset)); +} + +// ------------------------------------- + +/** +* Roll a field by a signed amount. +* Note: This will be made public later. [LIU] +*/ + +void +GregorianCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) { + roll((UCalendarDateFields) field, amount, status); +} + +void +GregorianCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) +{ + if((amount == 0) || U_FAILURE(status)) { + return; + } + + // J81 processing. (gregorian cutover) + UBool inCutoverMonth = FALSE; + int32_t cMonthLen=0; // 'c' for cutover; in days + int32_t cDayOfMonth=0; // no discontinuity: [0, cMonthLen) + double cMonthStart=0.0; // in ms + + // Common code - see if we're in the cutover month of the cutover year + if(get(UCAL_EXTENDED_YEAR, status) == fGregorianCutoverYear) { + switch (field) { + case UCAL_DAY_OF_MONTH: + case UCAL_WEEK_OF_MONTH: + { + int32_t max = monthLength(internalGet(UCAL_MONTH)); + UDate t = internalGetTime(); + // We subtract 1 from the DAY_OF_MONTH to make it zero-based, and an + // additional 10 if we are after the cutover. Thus the monthStart + // value will be correct iff we actually are in the cutover month. + cDayOfMonth = internalGet(UCAL_DAY_OF_MONTH) - ((t >= fGregorianCutover) ? 10 : 0); + cMonthStart = t - ((cDayOfMonth - 1) * kOneDay); + // A month containing the cutover is 10 days shorter. + if ((cMonthStart < fGregorianCutover) && + (cMonthStart + (cMonthLen=(max-10))*kOneDay >= fGregorianCutover)) { + inCutoverMonth = TRUE; + } + } + break; + default: + ; + } + } + + switch (field) { + case UCAL_WEEK_OF_YEAR: { + // Unlike WEEK_OF_MONTH, WEEK_OF_YEAR never shifts the day of the + // week. Also, rolling the week of the year can have seemingly + // strange effects simply because the year of the week of year + // may be different from the calendar year. For example, the + // date Dec 28, 1997 is the first day of week 1 of 1998 (if + // weeks start on Sunday and the minimal days in first week is + // <= 3). + int32_t woy = get(UCAL_WEEK_OF_YEAR, status); + // Get the ISO year, which matches the week of year. This + // may be one year before or after the calendar year. + int32_t isoYear = get(UCAL_YEAR_WOY, status); + int32_t isoDoy = internalGet(UCAL_DAY_OF_YEAR); + if (internalGet(UCAL_MONTH) == UCAL_JANUARY) { + if (woy >= 52) { + isoDoy += handleGetYearLength(isoYear); + } + } else { + if (woy == 1) { + isoDoy -= handleGetYearLength(isoYear - 1); + } + } + woy += amount; + // Do fast checks to avoid unnecessary computation: + if (woy < 1 || woy > 52) { + // Determine the last week of the ISO year. + // We do this using the standard formula we use + // everywhere in this file. If we can see that the + // days at the end of the year are going to fall into + // week 1 of the next year, we drop the last week by + // subtracting 7 from the last day of the year. + int32_t lastDoy = handleGetYearLength(isoYear); + int32_t lastRelDow = (lastDoy - isoDoy + internalGet(UCAL_DAY_OF_WEEK) - + getFirstDayOfWeek()) % 7; + if (lastRelDow < 0) lastRelDow += 7; + if ((6 - lastRelDow) >= getMinimalDaysInFirstWeek()) lastDoy -= 7; + int32_t lastWoy = weekNumber(lastDoy, lastRelDow + 1); + woy = ((woy + lastWoy - 1) % lastWoy) + 1; + } + set(UCAL_WEEK_OF_YEAR, woy); + set(UCAL_YEAR_WOY,isoYear); + return; + } + + case UCAL_DAY_OF_MONTH: + if( !inCutoverMonth ) { + Calendar::roll(field, amount, status); + return; + } else { + // [j81] 1582 special case for DOM + // The default computation works except when the current month + // contains the Gregorian cutover. We handle this special case + // here. [j81 - aliu] + double monthLen = cMonthLen * kOneDay; + double msIntoMonth = uprv_fmod(internalGetTime() - cMonthStart + + amount * kOneDay, monthLen); + if (msIntoMonth < 0) { + msIntoMonth += monthLen; + } +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: roll DOM %d -> %.0lf ms \n", + __FILE__, __LINE__,amount, cMonthLen, cMonthStart+msIntoMonth); +#endif + setTimeInMillis(cMonthStart + msIntoMonth, status); + return; + } + + case UCAL_WEEK_OF_MONTH: + if( !inCutoverMonth ) { + Calendar::roll(field, amount, status); + return; + } else { +#if defined (U_DEBUG_CAL) + fprintf(stderr, "%s:%d: roll WOM %d ??????????????????? \n", + __FILE__, __LINE__,amount); +#endif + // NOTE: following copied from the old + // GregorianCalendar::roll( WEEK_OF_MONTH ) code + + // This is tricky, because during the roll we may have to shift + // to a different day of the week. For example: + + // s m t w r f s + // 1 2 3 4 5 + // 6 7 8 9 10 11 12 + + // When rolling from the 6th or 7th back one week, we go to the + // 1st (assuming that the first partial week counts). The same + // thing happens at the end of the month. + + // The other tricky thing is that we have to figure out whether + // the first partial week actually counts or not, based on the + // minimal first days in the week. And we have to use the + // correct first day of the week to delineate the week + // boundaries. + + // Here's our algorithm. First, we find the real boundaries of + // the month. Then we discard the first partial week if it + // doesn't count in this locale. Then we fill in the ends with + // phantom days, so that the first partial week and the last + // partial week are full weeks. We then have a nice square + // block of weeks. We do the usual rolling within this block, + // as is done elsewhere in this method. If we wind up on one of + // the phantom days that we added, we recognize this and pin to + // the first or the last day of the month. Easy, eh? + + // Another wrinkle: To fix jitterbug 81, we have to make all this + // work in the oddball month containing the Gregorian cutover. + // This month is 10 days shorter than usual, and also contains + // a discontinuity in the days; e.g., the default cutover month + // is Oct 1582, and goes from day of month 4 to day of month 15. + + // Normalize the DAY_OF_WEEK so that 0 is the first day of the week + // in this locale. We have dow in 0..6. + int32_t dow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek(); + if (dow < 0) + dow += 7; + + // Find the day of month, compensating for cutover discontinuity. + int32_t dom = cDayOfMonth; + + // Find the day of the week (normalized for locale) for the first + // of the month. + int32_t fdm = (dow - dom + 1) % 7; + if (fdm < 0) + fdm += 7; + + // Get the first day of the first full week of the month, + // including phantom days, if any. Figure out if the first week + // counts or not; if it counts, then fill in phantom days. If + // not, advance to the first real full week (skip the partial week). + int32_t start; + if ((7 - fdm) < getMinimalDaysInFirstWeek()) + start = 8 - fdm; // Skip the first partial week + else + start = 1 - fdm; // This may be zero or negative + + // Get the day of the week (normalized for locale) for the last + // day of the month. + int32_t monthLen = cMonthLen; + int32_t ldm = (monthLen - dom + dow) % 7; + // We know monthLen >= DAY_OF_MONTH so we skip the += 7 step here. + + // Get the limit day for the blocked-off rectangular month; that + // is, the day which is one past the last day of the month, + // after the month has already been filled in with phantom days + // to fill out the last week. This day has a normalized DOW of 0. + int32_t limit = monthLen + 7 - ldm; + + // Now roll between start and (limit - 1). + int32_t gap = limit - start; + int32_t newDom = (dom + amount*7 - start) % gap; + if (newDom < 0) + newDom += gap; + newDom += start; + + // Finally, pin to the real start and end of the month. + if (newDom < 1) + newDom = 1; + if (newDom > monthLen) + newDom = monthLen; + + // Set the DAY_OF_MONTH. We rely on the fact that this field + // takes precedence over everything else (since all other fields + // are also set at this point). If this fact changes (if the + // disambiguation algorithm changes) then we will have to unset + // the appropriate fields here so that DAY_OF_MONTH is attended + // to. + + // If we are in the cutover month, manipulate ms directly. Don't do + // this in general because it doesn't work across DST boundaries + // (details, details). This takes care of the discontinuity. + setTimeInMillis(cMonthStart + (newDom-1)*kOneDay, status); + return; + } + + default: + Calendar::roll(field, amount, status); + return; + } +} + +// ------------------------------------- + + +/** +* Return the minimum value that this field could have, given the current date. +* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum(). +* @param field the time field. +* @return the minimum value that this field could have, given the current date. +* @deprecated ICU 2.6. Use getActualMinimum(UCalendarDateFields field) instead. +*/ +int32_t GregorianCalendar::getActualMinimum(EDateFields field) const +{ + return getMinimum((UCalendarDateFields)field); +} + +int32_t GregorianCalendar::getActualMinimum(EDateFields field, UErrorCode& /* status */) const +{ + return getMinimum((UCalendarDateFields)field); +} + +/** +* Return the minimum value that this field could have, given the current date. +* For the Gregorian calendar, this is the same as getMinimum() and getGreatestMinimum(). +* @param field the time field. +* @return the minimum value that this field could have, given the current date. +* @draft ICU 2.6. +*/ +int32_t GregorianCalendar::getActualMinimum(UCalendarDateFields field, UErrorCode& /* status */) const +{ + return getMinimum(field); +} + + +// ------------------------------------ + +/** +* Old year limits were least max 292269054, max 292278994. +*/ + +/** +* @stable ICU 2.0 +*/ +int32_t GregorianCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const { + return kGregorianCalendarLimits[field][limitType]; +} + +/** +* Return the maximum value that this field could have, given the current date. +* For example, with the date "Feb 3, 1997" and the DAY_OF_MONTH field, the actual +* maximum would be 28; for "Feb 3, 1996" it s 29. Similarly for a Hebrew calendar, +* for some years the actual maximum for MONTH is 12, and for others 13. +* @stable ICU 2.0 +*/ +int32_t GregorianCalendar::getActualMaximum(UCalendarDateFields field, UErrorCode& status) const +{ + /* It is a known limitation that the code here (and in getActualMinimum) + * won't behave properly at the extreme limits of GregorianCalendar's + * representable range (except for the code that handles the YEAR + * field). That's because the ends of the representable range are at + * odd spots in the year. For calendars with the default Gregorian + * cutover, these limits are Sun Dec 02 16:47:04 GMT 292269055 BC to Sun + * Aug 17 07:12:55 GMT 292278994 AD, somewhat different for non-GMT + * zones. As a result, if the calendar is set to Aug 1 292278994 AD, + * the actual maximum of DAY_OF_MONTH is 17, not 30. If the date is Mar + * 31 in that year, the actual maximum month might be Jul, whereas is + * the date is Mar 15, the actual maximum might be Aug -- depending on + * the precise semantics that are desired. Similar considerations + * affect all fields. Nonetheless, this effect is sufficiently arcane + * that we permit it, rather than complicating the code to handle such + * intricacies. - liu 8/20/98 + + * UPDATE: No longer true, since we have pulled in the limit values on + * the year. - Liu 11/6/00 */ + + switch (field) { + + case UCAL_YEAR: + /* The year computation is no different, in principle, from the + * others, however, the range of possible maxima is large. In + * addition, the way we know we've exceeded the range is different. + * For these reasons, we use the special case code below to handle + * this field. + * + * The actual maxima for YEAR depend on the type of calendar: + * + * Gregorian = May 17, 292275056 BC - Aug 17, 292278994 AD + * Julian = Dec 2, 292269055 BC - Jan 3, 292272993 AD + * Hybrid = Dec 2, 292269055 BC - Aug 17, 292278994 AD + * + * We know we've exceeded the maximum when either the month, date, + * time, or era changes in response to setting the year. We don't + * check for month, date, and time here because the year and era are + * sufficient to detect an invalid year setting. NOTE: If code is + * added to check the month and date in the future for some reason, + * Feb 29 must be allowed to shift to Mar 1 when setting the year. + */ + { + if(U_FAILURE(status)) return 0; + Calendar *cal = clone(); + if(!cal) { + status = U_MEMORY_ALLOCATION_ERROR; + return 0; + } + + cal->setLenient(TRUE); + + int32_t era = cal->get(UCAL_ERA, status); + UDate d = cal->getTime(status); + + /* Perform a binary search, with the invariant that lowGood is a + * valid year, and highBad is an out of range year. + */ + int32_t lowGood = kGregorianCalendarLimits[UCAL_YEAR][1]; + int32_t highBad = kGregorianCalendarLimits[UCAL_YEAR][2]+1; + while ((lowGood + 1) < highBad) { + int32_t y = (lowGood + highBad) / 2; + cal->set(UCAL_YEAR, y); + if (cal->get(UCAL_YEAR, status) == y && cal->get(UCAL_ERA, status) == era) { + lowGood = y; + } else { + highBad = y; + cal->setTime(d, status); // Restore original fields + } + } + + delete cal; + return lowGood; + } + + default: + return Calendar::getActualMaximum(field,status); + } +} + + +int32_t GregorianCalendar::handleGetExtendedYear() { + // the year to return + int32_t year = kEpochYear; + + // year field to use + int32_t yearField = UCAL_EXTENDED_YEAR; + + // There are three separate fields which could be used to + // derive the proper year. Use the one most recently set. + if (fStamp[yearField] < fStamp[UCAL_YEAR]) + yearField = UCAL_YEAR; + if (fStamp[yearField] < fStamp[UCAL_YEAR_WOY]) + yearField = UCAL_YEAR_WOY; + + // based on the "best" year field, get the year + switch(yearField) { + case UCAL_EXTENDED_YEAR: + year = internalGet(UCAL_EXTENDED_YEAR, kEpochYear); + break; + + case UCAL_YEAR: + { + // The year defaults to the epoch start, the era to AD + int32_t era = internalGet(UCAL_ERA, AD); + if (era == BC) { + year = 1 - internalGet(UCAL_YEAR, 1); // Convert to extended year + } else { + year = internalGet(UCAL_YEAR, kEpochYear); + } + } + break; + + case UCAL_YEAR_WOY: + year = handleGetExtendedYearFromWeekFields(internalGet(UCAL_YEAR_WOY), internalGet(UCAL_WEEK_OF_YEAR)); +#if defined (U_DEBUG_CAL) + // if(internalGet(UCAL_YEAR_WOY) != year) { + fprintf(stderr, "%s:%d: hGEYFWF[%d,%d] -> %d\n", + __FILE__, __LINE__,internalGet(UCAL_YEAR_WOY),internalGet(UCAL_WEEK_OF_YEAR),year); + //} +#endif + break; + + default: + year = kEpochYear; + } + return year; +} + +int32_t GregorianCalendar::handleGetExtendedYearFromWeekFields(int32_t yearWoy, int32_t woy) +{ + // convert year to extended form + int32_t era = internalGet(UCAL_ERA, AD); + if(era == BC) { + yearWoy = 1 - yearWoy; + } + return Calendar::handleGetExtendedYearFromWeekFields(yearWoy, woy); +} + + +// ------------------------------------- + +UBool +GregorianCalendar::inDaylightTime(UErrorCode& status) const +{ + if (U_FAILURE(status) || !getTimeZone().useDaylightTime()) + return FALSE; + + // Force an update of the state of the Calendar. + ((GregorianCalendar*)this)->complete(status); // cast away const + + return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE); +} + +// ------------------------------------- + +/** +* Return the ERA. We need a special method for this because the +* default ERA is AD, but a zero (unset) ERA is BC. +*/ +int32_t +GregorianCalendar::internalGetEra() const { + return isSet(UCAL_ERA) ? internalGet(UCAL_ERA) : (int32_t)AD; +} + +const char * +GregorianCalendar::getType() const { + //static const char kGregorianType = "gregorian"; + + return "gregorian"; +} + +/** + * The system maintains a static default century start date and Year. They are + * initialized the first time they are used. Once the system default century date + * and year are set, they do not change. + */ +static UDate gSystemDefaultCenturyStart = DBL_MIN; +static int32_t gSystemDefaultCenturyStartYear = -1; +static icu::UInitOnce gSystemDefaultCenturyInit = U_INITONCE_INITIALIZER; + + +UBool GregorianCalendar::haveDefaultCentury() const +{ + return TRUE; +} + +static void U_CALLCONV +initializeSystemDefaultCentury() +{ + // initialize systemDefaultCentury and systemDefaultCenturyYear based + // on the current time. They'll be set to 80 years before + // the current time. + UErrorCode status = U_ZERO_ERROR; + GregorianCalendar calendar(status); + if (U_SUCCESS(status)) { + calendar.setTime(Calendar::getNow(), status); + calendar.add(UCAL_YEAR, -80, status); + + gSystemDefaultCenturyStart = calendar.getTime(status); + gSystemDefaultCenturyStartYear = calendar.get(UCAL_YEAR, status); + } + // We have no recourse upon failure unless we want to propagate the failure + // out. +} + +UDate GregorianCalendar::defaultCenturyStart() const { + // lazy-evaluate systemDefaultCenturyStart + umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury); + return gSystemDefaultCenturyStart; +} + +int32_t GregorianCalendar::defaultCenturyStartYear() const { + // lazy-evaluate systemDefaultCenturyStartYear + umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury); + return gSystemDefaultCenturyStartYear; +} + +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_FORMATTING */ + +//eof |