icuSources/i18n/olsontz.cpp

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 **********************************************************************
   5 * Copyright (c) 2003-2013, International Business Machines
   6 * Corporation and others.  All Rights Reserved.
   7 **********************************************************************
   8 * Author: Alan Liu
   9 * Created: July 21 2003
  10 * Since: ICU 2.8
  11 **********************************************************************
  12 */
  13
  14 #include "utypeinfo.h"  // for 'typeid' to work
  15
  16 #include "olsontz.h"
  17
  18 #if !UCONFIG_NO_FORMATTING
  19
  20 #include "unicode/ures.h"
  21 #include "unicode/simpletz.h"
  22 #include "unicode/gregocal.h"
  23 #include "gregoimp.h"
  24 #include "cmemory.h"
  25 #include "uassert.h"
  26 #include "uvector.h"
  27 #include <float.h> // DBL_MAX
  28 #include "uresimp.h"
  29 #include "zonemeta.h"
  30 #include "umutex.h"
  31
  32 #ifdef U_DEBUG_TZ
  33 # include <stdio.h>
  34 # include "uresimp.h" // for debugging
  35
  36 static void debug_tz_loc(const char *f, int32_t l)
  37 {
  38   fprintf(stderr, "%s:%d: ", f, l);
  39 }
  40
  41 static void debug_tz_msg(const char *pat, ...)
  42 {
  43   va_list ap;
  44   va_start(ap, pat);
  45   vfprintf(stderr, pat, ap);
  46   fflush(stderr);
  47 }
  48 // must use double parens, i.e.:  U_DEBUG_TZ_MSG(("four is: %d",4));
  49 #define U_DEBUG_TZ_MSG(x) {debug_tz_loc(__FILE__,__LINE__);debug_tz_msg x;}
  50 #else
  51 #define U_DEBUG_TZ_MSG(x)
  52 #endif
  53
  54 static UBool arrayEqual(const void *a1, const void *a2, int32_t size) {
  55     if (a1 == NULL && a2 == NULL) {
  56         return TRUE;
  57     }
  58     if ((a1 != NULL && a2 == NULL) || (a1 == NULL && a2 != NULL)) {
  59         return FALSE;
  60     }
  61     if (a1 == a2) {
  62         return TRUE;
  63     }
  64
  65     return (uprv_memcmp(a1, a2, size) == 0);
  66 }
  67
  68 U_NAMESPACE_BEGIN
  69
  70 #define kTRANS          "trans"
  71 #define kTRANSPRE32     "transPre32"
  72 #define kTRANSPOST32    "transPost32"
  73 #define kTYPEOFFSETS    "typeOffsets"
  74 #define kTYPEMAP        "typeMap"
  75 #define kLINKS          "links"
  76 #define kFINALRULE      "finalRule"
  77 #define kFINALRAW       "finalRaw"
  78 #define kFINALYEAR      "finalYear"
  79
  80 #define SECONDS_PER_DAY (24*60*60)
  81
  82 static const int32_t ZEROS[] = {0,0};
  83
  84 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(OlsonTimeZone)
  85
  86 /**
  87  * Default constructor.  Creates a time zone with an empty ID and
  88  * a fixed GMT offset of zero.
  89  */
  90 /*OlsonTimeZone::OlsonTimeZone() : finalYear(INT32_MAX), finalMillis(DBL_MAX), finalZone(0), transitionRulesInitialized(FALSE) {
  91     clearTransitionRules();
  92     constructEmpty();
  93 }*/
  94
  95 /**
  96  * Construct a GMT+0 zone with no transitions.  This is done when a
  97  * constructor fails so the resultant object is well-behaved.
  98  */
  99 void OlsonTimeZone::constructEmpty() {
 100     canonicalID = NULL;
 101
 102     transitionCountPre32 = transitionCount32 = transitionCountPost32 = 0;
 103     transitionTimesPre32 = transitionTimes32 = transitionTimesPost32 = NULL;
 104
 105     typeMapData = NULL;
 106
 107     typeCount = 1;
 108     typeOffsets = ZEROS;
 109
 110     finalZone = NULL;
 111 }
 112
 113 /**
 114  * Construct from a resource bundle
 115  * @param top the top-level zoneinfo resource bundle.  This is used
 116  * to lookup the rule that `res' may refer to, if there is one.
 117  * @param res the resource bundle of the zone to be constructed
 118  * @param ec input-output error code
 119  */
 120 OlsonTimeZone::OlsonTimeZone(const UResourceBundle* top,
 121                              const UResourceBundle* res,
 122                              const UnicodeString& tzid,
 123                              UErrorCode& ec) :
 124   BasicTimeZone(tzid), finalZone(NULL)
 125 {
 126     clearTransitionRules();
 127     U_DEBUG_TZ_MSG(("OlsonTimeZone(%s)\n", ures_getKey((UResourceBundle*)res)));
 128     if ((top == NULL || res == NULL) && U_SUCCESS(ec)) {
 129         ec = U_ILLEGAL_ARGUMENT_ERROR;
 130     }
 131     if (U_SUCCESS(ec)) {
 132         // TODO -- clean up -- Doesn't work if res points to an alias
 133         //        // TODO remove nonconst casts below when ures_* API is fixed
 134         //        setID(ures_getKey((UResourceBundle*) res)); // cast away const
 135
 136         int32_t len;
 137         StackUResourceBundle r;
 138
 139         // Pre-32bit second transitions
 140         ures_getByKey(res, kTRANSPRE32, r.getAlias(), &ec);
 141         transitionTimesPre32 = ures_getIntVector(r.getAlias(), &len, &ec);
 142         transitionCountPre32 = static_cast<int16_t>(len >> 1);
 143         if (ec == U_MISSING_RESOURCE_ERROR) {
 144             // No pre-32bit transitions
 145             transitionTimesPre32 = NULL;
 146             transitionCountPre32 = 0;
 147             ec = U_ZERO_ERROR;
 148         } else if (U_SUCCESS(ec) && (len < 0 || len > 0x7FFF || (len & 1) != 0) /* len must be even */) {
 149             ec = U_INVALID_FORMAT_ERROR;
 150         }
 151
 152         // 32bit second transitions
 153         ures_getByKey(res, kTRANS, r.getAlias(), &ec);
 154         transitionTimes32 = ures_getIntVector(r.getAlias(), &len, &ec);
 155         transitionCount32 = static_cast<int16_t>(len);
 156         if (ec == U_MISSING_RESOURCE_ERROR) {
 157             // No 32bit transitions
 158             transitionTimes32 = NULL;
 159             transitionCount32 = 0;
 160             ec = U_ZERO_ERROR;
 161         } else if (U_SUCCESS(ec) && (len < 0 || len > 0x7FFF)) {
 162             ec = U_INVALID_FORMAT_ERROR;
 163         }
 164
 165         // Post-32bit second transitions
 166         ures_getByKey(res, kTRANSPOST32, r.getAlias(), &ec);
 167         transitionTimesPost32 = ures_getIntVector(r.getAlias(), &len, &ec);
 168         transitionCountPost32 = static_cast<int16_t>(len >> 1);
 169         if (ec == U_MISSING_RESOURCE_ERROR) {
 170             // No pre-32bit transitions
 171             transitionTimesPost32 = NULL;
 172             transitionCountPost32 = 0;
 173             ec = U_ZERO_ERROR;
 174         } else if (U_SUCCESS(ec) && (len < 0 || len > 0x7FFF || (len & 1) != 0) /* len must be even */) {
 175             ec = U_INVALID_FORMAT_ERROR;
 176         }
 177
 178         // Type offsets list must be of even size, with size >= 2
 179         ures_getByKey(res, kTYPEOFFSETS, r.getAlias(), &ec);
 180         typeOffsets = ures_getIntVector(r.getAlias(), &len, &ec);
 181         if (U_SUCCESS(ec) && (len < 2 || len > 0x7FFE || (len & 1) != 0)) {
 182             ec = U_INVALID_FORMAT_ERROR;
 183         }
 184         typeCount = (int16_t) len >> 1;
 185
 186         // Type map data must be of the same size as the transition count
 187         typeMapData =  NULL;
 188         if (transitionCount() > 0) {
 189             ures_getByKey(res, kTYPEMAP, r.getAlias(), &ec);
 190             typeMapData = ures_getBinary(r.getAlias(), &len, &ec);
 191             if (ec == U_MISSING_RESOURCE_ERROR) {
 192                 // no type mapping data
 193                 ec = U_INVALID_FORMAT_ERROR;
 194             } else if (U_SUCCESS(ec) && len != transitionCount()) {
 195                 ec = U_INVALID_FORMAT_ERROR;
 196             }
 197         }
 198
 199         // Process final rule and data, if any
 200         if (U_SUCCESS(ec)) {
 201             const UChar *ruleIdUStr = ures_getStringByKey(res, kFINALRULE, &len, &ec);
 202             ures_getByKey(res, kFINALRAW, r.getAlias(), &ec);
 203             int32_t ruleRaw = ures_getInt(r.getAlias(), &ec);
 204             ures_getByKey(res, kFINALYEAR, r.getAlias(), &ec);
 205             int32_t ruleYear = ures_getInt(r.getAlias(), &ec);
 206             if (U_SUCCESS(ec)) {
 207                 UnicodeString ruleID(TRUE, ruleIdUStr, len);
 208                 UResourceBundle *rule = TimeZone::loadRule(top, ruleID, NULL, ec);
 209                 const int32_t *ruleData = ures_getIntVector(rule, &len, &ec);
 210                 if (U_SUCCESS(ec) && len == 11) {
 211                     UnicodeString emptyStr;
 212                     finalZone = new SimpleTimeZone(
 213                         ruleRaw * U_MILLIS_PER_SECOND,
 214                         emptyStr,
 215                         (int8_t)ruleData[0], (int8_t)ruleData[1], (int8_t)ruleData[2],
 216                         ruleData[3] * U_MILLIS_PER_SECOND,
 217                         (SimpleTimeZone::TimeMode) ruleData[4],
 218                         (int8_t)ruleData[5], (int8_t)ruleData[6], (int8_t)ruleData[7],
 219                         ruleData[8] * U_MILLIS_PER_SECOND,
 220                         (SimpleTimeZone::TimeMode) ruleData[9],
 221                         ruleData[10] * U_MILLIS_PER_SECOND, ec);
 222                     if (finalZone == NULL) {
 223                         ec = U_MEMORY_ALLOCATION_ERROR;
 224                     } else {
 225                         finalStartYear = ruleYear;
 226
 227                         // Note: Setting finalStartYear to the finalZone is problematic.  When a date is around
 228                         // year boundary, SimpleTimeZone may return false result when DST is observed at the
 229                         // beginning of year.  We could apply safe margin (day or two), but when one of recurrent
 230                         // rules falls around year boundary, it could return false result.  Without setting the
 231                         // start year, finalZone works fine around the year boundary of the start year.
 232
 233                         // finalZone->setStartYear(finalStartYear);
 234
 235
 236                         // Compute the millis for Jan 1, 0:00 GMT of the finalYear
 237
 238                         // Note: finalStartMillis is used for detecting either if
 239                         // historic transition data or finalZone to be used.  In an
 240                         // extreme edge case - for example, two transitions fall into
 241                         // small windows of time around the year boundary, this may
 242                         // result incorrect offset computation.  But I think it will
 243                         // never happen practically.  Yoshito - Feb 20, 2010
 244                         finalStartMillis = Grego::fieldsToDay(finalStartYear, 0, 1) * U_MILLIS_PER_DAY;
 245                     }
 246                 } else {
 247                     ec = U_INVALID_FORMAT_ERROR;
 248                 }
 249                 ures_close(rule);
 250             } else if (ec == U_MISSING_RESOURCE_ERROR) {
 251                 // No final zone
 252                 ec = U_ZERO_ERROR;
 253             }
 254         }
 255
 256         // initialize canonical ID
 257         canonicalID = ZoneMeta::getCanonicalCLDRID(tzid, ec);
 258     }
 259
 260     if (U_FAILURE(ec)) {
 261         constructEmpty();
 262     }
 263 }
 264
 265 /**
 266  * Copy constructor
 267  */
 268 OlsonTimeZone::OlsonTimeZone(const OlsonTimeZone& other) :
 269     BasicTimeZone(other), finalZone(0) {
 270     *this = other;
 271 }
 272
 273 /**
 274  * Assignment operator
 275  */
 276 OlsonTimeZone& OlsonTimeZone::operator=(const OlsonTimeZone& other) {
 277     canonicalID = other.canonicalID;
 278
 279     transitionTimesPre32 = other.transitionTimesPre32;
 280     transitionTimes32 = other.transitionTimes32;
 281     transitionTimesPost32 = other.transitionTimesPost32;
 282
 283     transitionCountPre32 = other.transitionCountPre32;
 284     transitionCount32 = other.transitionCount32;
 285     transitionCountPost32 = other.transitionCountPost32;
 286
 287     typeCount = other.typeCount;
 288     typeOffsets = other.typeOffsets;
 289     typeMapData = other.typeMapData;
 290
 291     delete finalZone;
 292     finalZone = (other.finalZone != 0) ? other.finalZone->clone() : 0;
 293
 294     finalStartYear = other.finalStartYear;
 295     finalStartMillis = other.finalStartMillis;
 296
 297     clearTransitionRules();
 298
 299     return *this;
 300 }
 301
 302 /**
 303  * Destructor
 304  */
 305 OlsonTimeZone::~OlsonTimeZone() {
 306     deleteTransitionRules();
 307     delete finalZone;
 308 }
 309
 310 /**
 311  * Returns true if the two TimeZone objects are equal.
 312  */
 313 UBool OlsonTimeZone::operator==(const TimeZone& other) const {
 314     return ((this == &other) ||
 315             (typeid(*this) == typeid(other) &&
 316             TimeZone::operator==(other) &&
 317             hasSameRules(other)));
 318 }
 319
 320 /**
 321  * TimeZone API.
 322  */
 323 OlsonTimeZone* OlsonTimeZone::clone() const {
 324     return new OlsonTimeZone(*this);
 325 }
 326
 327 /**
 328  * TimeZone API.
 329  */
 330 int32_t OlsonTimeZone::getOffset(uint8_t era, int32_t year, int32_t month,
 331                                  int32_t dom, uint8_t dow,
 332                                  int32_t millis, UErrorCode& ec) const {
 333     if (month < UCAL_JANUARY || month > UCAL_DECEMBER) {
 334         if (U_SUCCESS(ec)) {
 335             ec = U_ILLEGAL_ARGUMENT_ERROR;
 336         }
 337         return 0;
 338     } else {
 339         return getOffset(era, year, month, dom, dow, millis,
 340                          Grego::monthLength(year, month),
 341                          ec);
 342     }
 343 }
 344
 345 /**
 346  * TimeZone API.
 347  */
 348 int32_t OlsonTimeZone::getOffset(uint8_t era, int32_t year, int32_t month,
 349                                  int32_t dom, uint8_t dow,
 350                                  int32_t millis, int32_t monthLength,
 351                                  UErrorCode& ec) const {
 352     if (U_FAILURE(ec)) {
 353         return 0;
 354     }
 355
 356     if ((era != GregorianCalendar::AD && era != GregorianCalendar::BC)
 357         || month < UCAL_JANUARY
 358         || month > UCAL_DECEMBER
 359         || dom < 1
 360         || dom > monthLength
 361         || dow < UCAL_SUNDAY
 362         || dow > UCAL_SATURDAY
 363         || millis < 0
 364         || millis >= U_MILLIS_PER_DAY
 365         || monthLength < 28
 366         || monthLength > 31) {
 367         ec = U_ILLEGAL_ARGUMENT_ERROR;
 368         return 0;
 369     }
 370
 371     if (era == GregorianCalendar::BC) {
 372         year = -year;
 373     }
 374
 375     if (finalZone != NULL && year >= finalStartYear) {
 376         return finalZone->getOffset(era, year, month, dom, dow,
 377                                     millis, monthLength, ec);
 378     }
 379
 380     // Compute local epoch millis from input fields
 381     UDate date = (UDate)(Grego::fieldsToDay(year, month, dom) * U_MILLIS_PER_DAY + millis);
 382     int32_t rawoff, dstoff;
 383     getHistoricalOffset(date, TRUE, kDaylight, kStandard, rawoff, dstoff);
 384     return rawoff + dstoff;
 385 }
 386
 387 /**
 388  * TimeZone API.
 389  */
 390 void OlsonTimeZone::getOffset(UDate date, UBool local, int32_t& rawoff,
 391                               int32_t& dstoff, UErrorCode& ec) const {
 392     if (U_FAILURE(ec)) {
 393         return;
 394     }
 395     if (finalZone != NULL && date >= finalStartMillis) {
 396         finalZone->getOffset(date, local, rawoff, dstoff, ec);
 397     } else {
 398         getHistoricalOffset(date, local, kFormer, kLatter, rawoff, dstoff);
 399     }
 400 }
 401
 402 void
 403 OlsonTimeZone::getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt,
 404                                   int32_t& rawoff, int32_t& dstoff, UErrorCode& ec) const {
 405     if (U_FAILURE(ec)) {
 406         return;
 407     }
 408     if (finalZone != NULL && date >= finalStartMillis) {
 409         finalZone->getOffsetFromLocal(date, nonExistingTimeOpt, duplicatedTimeOpt, rawoff, dstoff, ec);
 410     } else {
 411         getHistoricalOffset(date, TRUE, nonExistingTimeOpt, duplicatedTimeOpt, rawoff, dstoff);
 412     }
 413 }
 414
 415
 416 /**
 417  * TimeZone API.
 418  */
 419 void OlsonTimeZone::setRawOffset(int32_t /*offsetMillis*/) {
 420     // We don't support this operation, since OlsonTimeZones are
 421     // immutable (except for the ID, which is in the base class).
 422
 423     // Nothing to do!
 424 }
 425
 426 /**
 427  * TimeZone API.
 428  */
 429 int32_t OlsonTimeZone::getRawOffset() const {
 430     UErrorCode ec = U_ZERO_ERROR;
 431     int32_t raw, dst;
 432     getOffset((double) uprv_getUTCtime() * U_MILLIS_PER_SECOND,
 433               FALSE, raw, dst, ec);
 434     return raw;
 435 }
 436
 437 #if defined U_DEBUG_TZ
 438 void printTime(double ms) {
 439             int32_t year, month, dom, dow;
 440             double millis=0;
 441             double days = ClockMath::floorDivide(((double)ms), (double)U_MILLIS_PER_DAY, millis);
 442
 443             Grego::dayToFields(days, year, month, dom, dow);
 444             U_DEBUG_TZ_MSG(("   getHistoricalOffset:  time %.1f (%04d.%02d.%02d+%.1fh)\n", ms,
 445                             year, month+1, dom, (millis/kOneHour)));
 446     }
 447 #endif
 448
 449 int64_t
 450 OlsonTimeZone::transitionTimeInSeconds(int16_t transIdx) const {
 451     U_ASSERT(transIdx >= 0 && transIdx < transitionCount());
 452
 453     if (transIdx < transitionCountPre32) {
 454         return (((int64_t)((uint32_t)transitionTimesPre32[transIdx << 1])) << 32)
 455             | ((int64_t)((uint32_t)transitionTimesPre32[(transIdx << 1) + 1]));
 456     }
 457
 458     transIdx -= transitionCountPre32;
 459     if (transIdx < transitionCount32) {
 460         return (int64_t)transitionTimes32[transIdx];
 461     }
 462
 463     transIdx -= transitionCount32;
 464     return (((int64_t)((uint32_t)transitionTimesPost32[transIdx << 1])) << 32)
 465         | ((int64_t)((uint32_t)transitionTimesPost32[(transIdx << 1) + 1]));
 466 }
 467
 468 // Maximum absolute offset in seconds (86400 seconds = 1 day)
 469 // getHistoricalOffset uses this constant as safety margin of
 470 // quick zone transition checking.
 471 #define MAX_OFFSET_SECONDS 86400
 472
 473 void
 474 OlsonTimeZone::getHistoricalOffset(UDate date, UBool local,
 475                                    int32_t NonExistingTimeOpt, int32_t DuplicatedTimeOpt,
 476                                    int32_t& rawoff, int32_t& dstoff) const {
 477     U_DEBUG_TZ_MSG(("getHistoricalOffset(%.1f, %s, %d, %d, raw, dst)\n",
 478         date, local?"T":"F", NonExistingTimeOpt, DuplicatedTimeOpt));
 479 #if defined U_DEBUG_TZ
 480         printTime(date*1000.0);
 481 #endif
 482     int16_t transCount = transitionCount();
 483
 484     if (transCount > 0) {
 485         double sec = uprv_floor(date / U_MILLIS_PER_SECOND);
 486         if (!local && sec < transitionTimeInSeconds(0)) {
 487             // Before the first transition time
 488             rawoff = initialRawOffset() * U_MILLIS_PER_SECOND;
 489             dstoff = initialDstOffset() * U_MILLIS_PER_SECOND;
 490         } else {
 491             // Linear search from the end is the fastest approach, since
 492             // most lookups will happen at/near the end.
 493             int16_t transIdx;
 494             for (transIdx = transCount - 1; transIdx >= 0; transIdx--) {
 495                 int64_t transition = transitionTimeInSeconds(transIdx);
 496
 497                 if (local && (sec >= (transition - MAX_OFFSET_SECONDS))) {
 498                     int32_t offsetBefore = zoneOffsetAt(transIdx - 1);
 499                     UBool dstBefore = dstOffsetAt(transIdx - 1) != 0;
 500
 501                     int32_t offsetAfter = zoneOffsetAt(transIdx);
 502                     UBool dstAfter = dstOffsetAt(transIdx) != 0;
 503
 504                     UBool dstToStd = dstBefore && !dstAfter;
 505                     UBool stdToDst = !dstBefore && dstAfter;
 506
 507                     if (offsetAfter - offsetBefore >= 0) {
 508                         // Positive transition, which makes a non-existing local time range
 509                         if (((NonExistingTimeOpt & kStdDstMask) == kStandard && dstToStd)
 510                                 || ((NonExistingTimeOpt & kStdDstMask) == kDaylight && stdToDst)) {
 511                             transition += offsetBefore;
 512                         } else if (((NonExistingTimeOpt & kStdDstMask) == kStandard && stdToDst)
 513                                 || ((NonExistingTimeOpt & kStdDstMask) == kDaylight && dstToStd)) {
 514                             transition += offsetAfter;
 515                         } else if ((NonExistingTimeOpt & kFormerLatterMask) == kLatter) {
 516                             transition += offsetBefore;
 517                         } else {
 518                             // Interprets the time with rule before the transition,
 519                             // default for non-existing time range
 520                             transition += offsetAfter;
 521                         }
 522                     } else {
 523                         // Negative transition, which makes a duplicated local time range
 524                         if (((DuplicatedTimeOpt & kStdDstMask) == kStandard && dstToStd)
 525                                 || ((DuplicatedTimeOpt & kStdDstMask) == kDaylight && stdToDst)) {
 526                             transition += offsetAfter;
 527                         } else if (((DuplicatedTimeOpt & kStdDstMask) == kStandard && stdToDst)
 528                                 || ((DuplicatedTimeOpt & kStdDstMask) == kDaylight && dstToStd)) {
 529                             transition += offsetBefore;
 530                         } else if ((DuplicatedTimeOpt & kFormerLatterMask) == kFormer) {
 531                             transition += offsetBefore;
 532                         } else {
 533                             // Interprets the time with rule after the transition,
 534                             // default for duplicated local time range
 535                             transition += offsetAfter;
 536                         }
 537                     }
 538                 }
 539                 if (sec >= transition) {
 540                     break;
 541                 }
 542             }
 543             // transIdx could be -1 when local=true
 544             rawoff = rawOffsetAt(transIdx) * U_MILLIS_PER_SECOND;
 545             dstoff = dstOffsetAt(transIdx) * U_MILLIS_PER_SECOND;
 546         }
 547     } else {
 548         // No transitions, single pair of offsets only
 549         rawoff = initialRawOffset() * U_MILLIS_PER_SECOND;
 550         dstoff = initialDstOffset() * U_MILLIS_PER_SECOND;
 551     }
 552     U_DEBUG_TZ_MSG(("getHistoricalOffset(%.1f, %s, %d, %d, raw, dst) - raw=%d, dst=%d\n",
 553         date, local?"T":"F", NonExistingTimeOpt, DuplicatedTimeOpt, rawoff, dstoff));
 554 }
 555
 556 /**
 557  * TimeZone API.
 558  */
 559 UBool OlsonTimeZone::useDaylightTime() const {
 560     // If DST was observed in 1942 (for example) but has never been
 561     // observed from 1943 to the present, most clients will expect
 562     // this method to return FALSE.  This method determines whether
 563     // DST is in use in the current year (at any point in the year)
 564     // and returns TRUE if so.
 565
 566     UDate current = uprv_getUTCtime();
 567     if (finalZone != NULL && current >= finalStartMillis) {
 568         return finalZone->useDaylightTime();
 569     }
 570
 571     int32_t year, month, dom, dow, doy, mid;
 572     Grego::timeToFields(current, year, month, dom, dow, doy, mid);
 573
 574     // Find start of this year, and start of next year
 575     double start = Grego::fieldsToDay(year, 0, 1) * SECONDS_PER_DAY;
 576     double limit = Grego::fieldsToDay(year+1, 0, 1) * SECONDS_PER_DAY;
 577
 578     // Return TRUE if DST is observed at any time during the current
 579     // year.
 580     for (int16_t i = 0; i < transitionCount(); ++i) {
 581         double transition = (double)transitionTimeInSeconds(i);
 582         if (transition >= limit) {
 583             break;
 584         }
 585         if ((transition >= start && dstOffsetAt(i) != 0)
 586                 || (transition > start && dstOffsetAt(i - 1) != 0)) {
 587             return TRUE;
 588         }
 589     }
 590     return FALSE;
 591 }
 592 int32_t
 593 OlsonTimeZone::getDSTSavings() const{
 594     if (finalZone != NULL){
 595         return finalZone->getDSTSavings();
 596     }
 597     return TimeZone::getDSTSavings();
 598 }
 599 /**
 600  * TimeZone API.
 601  */
 602 UBool OlsonTimeZone::inDaylightTime(UDate date, UErrorCode& ec) const {
 603     int32_t raw, dst;
 604     getOffset(date, FALSE, raw, dst, ec);
 605     return dst != 0;
 606 }
 607
 608 UBool
 609 OlsonTimeZone::hasSameRules(const TimeZone &other) const {
 610     if (this == &other) {
 611         return TRUE;
 612     }
 613     const OlsonTimeZone* z = dynamic_cast<const OlsonTimeZone*>(&other);
 614     if (z == NULL) {
 615         return FALSE;
 616     }
 617
 618     // [sic] pointer comparison: typeMapData points into
 619     // memory-mapped or DLL space, so if two zones have the same
 620     // pointer, they are equal.
 621     if (typeMapData == z->typeMapData) {
 622         return TRUE;
 623     }
 624
 625     // If the pointers are not equal, the zones may still
 626     // be equal if their rules and transitions are equal
 627     if ((finalZone == NULL && z->finalZone != NULL)
 628         || (finalZone != NULL && z->finalZone == NULL)
 629         || (finalZone != NULL && z->finalZone != NULL && *finalZone != *z->finalZone)) {
 630         return FALSE;
 631     }
 632
 633     if (finalZone != NULL) {
 634         if (finalStartYear != z->finalStartYear || finalStartMillis != z->finalStartMillis) {
 635             return FALSE;
 636         }
 637     }
 638     if (typeCount != z->typeCount
 639         || transitionCountPre32 != z->transitionCountPre32
 640         || transitionCount32 != z->transitionCount32
 641         || transitionCountPost32 != z->transitionCountPost32) {
 642         return FALSE;
 643     }
 644
 645     return
 646         arrayEqual(transitionTimesPre32, z->transitionTimesPre32, sizeof(transitionTimesPre32[0]) * transitionCountPre32 << 1)
 647         && arrayEqual(transitionTimes32, z->transitionTimes32, sizeof(transitionTimes32[0]) * transitionCount32)
 648         && arrayEqual(transitionTimesPost32, z->transitionTimesPost32, sizeof(transitionTimesPost32[0]) * transitionCountPost32 << 1)
 649         && arrayEqual(typeOffsets, z->typeOffsets, sizeof(typeOffsets[0]) * typeCount << 1)
 650         && arrayEqual(typeMapData, z->typeMapData, sizeof(typeMapData[0]) * transitionCount());
 651 }
 652
 653 void
 654 OlsonTimeZone::clearTransitionRules(void) {
 655     initialRule = NULL;
 656     firstTZTransition = NULL;
 657     firstFinalTZTransition = NULL;
 658     historicRules = NULL;
 659     historicRuleCount = 0;
 660     finalZoneWithStartYear = NULL;
 661     firstTZTransitionIdx = 0;
 662     transitionRulesInitOnce.reset();
 663 }
 664
 665 void
 666 OlsonTimeZone::deleteTransitionRules(void) {
 667     if (initialRule != NULL) {
 668         delete initialRule;
 669     }
 670     if (firstTZTransition != NULL) {
 671         delete firstTZTransition;
 672     }
 673     if (firstFinalTZTransition != NULL) {
 674         delete firstFinalTZTransition;
 675     }
 676     if (finalZoneWithStartYear != NULL) {
 677         delete finalZoneWithStartYear;
 678     }
 679     if (historicRules != NULL) {
 680         for (int i = 0; i < historicRuleCount; i++) {
 681             if (historicRules[i] != NULL) {
 682                 delete historicRules[i];
 683             }
 684         }
 685         uprv_free(historicRules);
 686     }
 687     clearTransitionRules();
 688 }
 689
 690 /*
 691  * Lazy transition rules initializer
 692  */
 693
 694 static void U_CALLCONV initRules(OlsonTimeZone *This, UErrorCode &status) {
 695     This->initTransitionRules(status);
 696 }
 697
 698 void
 699 OlsonTimeZone::checkTransitionRules(UErrorCode& status) const {
 700     OlsonTimeZone *ncThis = const_cast<OlsonTimeZone *>(this);
 701     umtx_initOnce(ncThis->transitionRulesInitOnce, &initRules, ncThis, status);
 702 }
 703
 704 void
 705 OlsonTimeZone::initTransitionRules(UErrorCode& status) {
 706     if(U_FAILURE(status)) {
 707         return;
 708     }
 709     deleteTransitionRules();
 710     UnicodeString tzid;
 711     getID(tzid);
 712
 713     UnicodeString stdName = tzid + UNICODE_STRING_SIMPLE("(STD)");
 714     UnicodeString dstName = tzid + UNICODE_STRING_SIMPLE("(DST)");
 715
 716     int32_t raw, dst;
 717
 718     // Create initial rule
 719     raw = initialRawOffset() * U_MILLIS_PER_SECOND;
 720     dst = initialDstOffset() * U_MILLIS_PER_SECOND;
 721     initialRule = new InitialTimeZoneRule((dst == 0 ? stdName : dstName), raw, dst);
 722     // Check to make sure initialRule was created
 723     if (initialRule == NULL) {
 724         status = U_MEMORY_ALLOCATION_ERROR;
 725         deleteTransitionRules();
 726         return;
 727     }
 728
 729     int32_t transCount = transitionCount();
 730     if (transCount > 0) {
 731         int16_t transitionIdx, typeIdx;
 732
 733         // We probably no longer need to check the first "real" transition
 734         // here, because the new tzcode remove such transitions already.
 735         // For now, keeping this code for just in case. Feb 19, 2010 Yoshito
 736         firstTZTransitionIdx = 0;
 737         for (transitionIdx = 0; transitionIdx < transCount; transitionIdx++) {
 738             if (typeMapData[transitionIdx] != 0) { // type 0 is the initial type
 739                 break;
 740             }
 741             firstTZTransitionIdx++;
 742         }
 743         if (transitionIdx == transCount) {
 744             // Actually no transitions...
 745         } else {
 746             // Build historic rule array
 747             UDate* times = (UDate*)uprv_malloc(sizeof(UDate)*transCount); /* large enough to store all transition times */
 748             if (times == NULL) {
 749                 status = U_MEMORY_ALLOCATION_ERROR;
 750                 deleteTransitionRules();
 751                 return;
 752             }
 753             for (typeIdx = 0; typeIdx < typeCount; typeIdx++) {
 754                 // Gather all start times for each pair of offsets
 755                 int32_t nTimes = 0;
 756                 for (transitionIdx = firstTZTransitionIdx; transitionIdx < transCount; transitionIdx++) {
 757                     if (typeIdx == (int16_t)typeMapData[transitionIdx]) {
 758                         UDate tt = (UDate)transitionTime(transitionIdx);
 759                         if (finalZone == NULL || tt <= finalStartMillis) {
 760                             // Exclude transitions after finalMillis
 761                             times[nTimes++] = tt;
 762                         }
 763                     }
 764                 }
 765                 if (nTimes > 0) {
 766                     // Create a TimeArrayTimeZoneRule
 767                     raw = typeOffsets[typeIdx << 1] * U_MILLIS_PER_SECOND;
 768                     dst = typeOffsets[(typeIdx << 1) + 1] * U_MILLIS_PER_SECOND;
 769                     if (historicRules == NULL) {
 770                         historicRuleCount = typeCount;
 771                         historicRules = (TimeArrayTimeZoneRule**)uprv_malloc(sizeof(TimeArrayTimeZoneRule*)*historicRuleCount);
 772                         if (historicRules == NULL) {
 773                             status = U_MEMORY_ALLOCATION_ERROR;
 774                             deleteTransitionRules();
 775                             uprv_free(times);
 776                             return;
 777                         }
 778                         for (int i = 0; i < historicRuleCount; i++) {
 779                             // Initialize TimeArrayTimeZoneRule pointers as NULL
 780                             historicRules[i] = NULL;
 781                         }
 782                     }
 783                     historicRules[typeIdx] = new TimeArrayTimeZoneRule((dst == 0 ? stdName : dstName),
 784                         raw, dst, times, nTimes, DateTimeRule::UTC_TIME);
 785                     // Check for memory allocation error
 786                     if (historicRules[typeIdx] == NULL) {
 787                         status = U_MEMORY_ALLOCATION_ERROR;
 788                         deleteTransitionRules();
 789                         return;
 790                     }
 791                 }
 792             }
 793             uprv_free(times);
 794
 795             // Create initial transition
 796             typeIdx = (int16_t)typeMapData[firstTZTransitionIdx];
 797             firstTZTransition = new TimeZoneTransition((UDate)transitionTime(firstTZTransitionIdx),
 798                     *initialRule, *historicRules[typeIdx]);
 799             // Check to make sure firstTZTransition was created.
 800             if (firstTZTransition == NULL) {
 801                 status = U_MEMORY_ALLOCATION_ERROR;
 802                 deleteTransitionRules();
 803                 return;
 804             }
 805         }
 806     }
 807     if (finalZone != NULL) {
 808         // Get the first occurence of final rule starts
 809         UDate startTime = (UDate)finalStartMillis;
 810         TimeZoneRule *firstFinalRule = NULL;
 811
 812         if (finalZone->useDaylightTime()) {
 813             /*
 814              * Note: When an OlsonTimeZone is constructed, we should set the final year
 815              * as the start year of finalZone.  However, the bounday condition used for
 816              * getting offset from finalZone has some problems.
 817              * For now, we do not set the valid start year when the construction time
 818              * and create a clone and set the start year when extracting rules.
 819              */
 820             finalZoneWithStartYear = finalZone->clone();
 821             // Check to make sure finalZone was actually cloned.
 822             if (finalZoneWithStartYear == NULL) {
 823                 status = U_MEMORY_ALLOCATION_ERROR;
 824                 deleteTransitionRules();
 825                 return;
 826             }
 827             finalZoneWithStartYear->setStartYear(finalStartYear);
 828
 829             TimeZoneTransition tzt;
 830             finalZoneWithStartYear->getNextTransition(startTime, false, tzt);
 831             firstFinalRule  = tzt.getTo()->clone();
 832             // Check to make sure firstFinalRule received proper clone.
 833             if (firstFinalRule == NULL) {
 834                 status = U_MEMORY_ALLOCATION_ERROR;
 835                 deleteTransitionRules();
 836                 return;
 837             }
 838             startTime = tzt.getTime();
 839         } else {
 840             // final rule with no transitions
 841             finalZoneWithStartYear = finalZone->clone();
 842             // Check to make sure finalZone was actually cloned.
 843             if (finalZoneWithStartYear == NULL) {
 844                 status = U_MEMORY_ALLOCATION_ERROR;
 845                 deleteTransitionRules();
 846                 return;
 847             }
 848             finalZone->getID(tzid);
 849             firstFinalRule = new TimeArrayTimeZoneRule(tzid,
 850                 finalZone->getRawOffset(), 0, &startTime, 1, DateTimeRule::UTC_TIME);
 851             // Check firstFinalRule was properly created.
 852             if (firstFinalRule == NULL) {
 853                 status = U_MEMORY_ALLOCATION_ERROR;
 854                 deleteTransitionRules();
 855                 return;
 856             }
 857         }
 858         TimeZoneRule *prevRule = NULL;
 859         if (transCount > 0) {
 860             prevRule = historicRules[typeMapData[transCount - 1]];
 861         }
 862         if (prevRule == NULL) {
 863             // No historic transitions, but only finalZone available
 864             prevRule = initialRule;
 865         }
 866         firstFinalTZTransition = new TimeZoneTransition();
 867         // Check to make sure firstFinalTZTransition was created before dereferencing
 868         if (firstFinalTZTransition == NULL) {
 869             status = U_MEMORY_ALLOCATION_ERROR;
 870             deleteTransitionRules();
 871             return;
 872         }
 873         firstFinalTZTransition->setTime(startTime);
 874         firstFinalTZTransition->adoptFrom(prevRule->clone());
 875         firstFinalTZTransition->adoptTo(firstFinalRule);
 876     }
 877 }
 878
 879 UBool
 880 OlsonTimeZone::getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const {
 881     UErrorCode status = U_ZERO_ERROR;
 882     checkTransitionRules(status);
 883     if (U_FAILURE(status)) {
 884         return FALSE;
 885     }
 886
 887     if (finalZone != NULL) {
 888         if (inclusive && base == firstFinalTZTransition->getTime()) {
 889             result = *firstFinalTZTransition;
 890             return TRUE;
 891         } else if (base >= firstFinalTZTransition->getTime()) {
 892             if (finalZone->useDaylightTime()) {
 893                 //return finalZone->getNextTransition(base, inclusive, result);
 894                 return finalZoneWithStartYear->getNextTransition(base, inclusive, result);
 895             } else {
 896                 // No more transitions
 897                 return FALSE;
 898             }
 899         }
 900     }
 901     if (historicRules != NULL) {
 902         // Find a historical transition
 903         int16_t transCount = transitionCount();
 904         int16_t ttidx = transCount - 1;
 905         for (; ttidx >= firstTZTransitionIdx; ttidx--) {
 906             UDate t = (UDate)transitionTime(ttidx);
 907             if (base > t || (!inclusive && base == t)) {
 908                 break;
 909             }
 910         }
 911         if (ttidx == transCount - 1)  {
 912             if (firstFinalTZTransition != NULL) {
 913                 result = *firstFinalTZTransition;
 914                 return TRUE;
 915             } else {
 916                 return FALSE;
 917             }
 918         } else if (ttidx < firstTZTransitionIdx) {
 919             result = *firstTZTransition;
 920             return TRUE;
 921         } else {
 922             // Create a TimeZoneTransition
 923             TimeZoneRule *to = historicRules[typeMapData[ttidx + 1]];
 924             TimeZoneRule *from = historicRules[typeMapData[ttidx]];
 925             UDate startTime = (UDate)transitionTime(ttidx+1);
 926
 927             // The transitions loaded from zoneinfo.res may contain non-transition data
 928             UnicodeString fromName, toName;
 929             from->getName(fromName);
 930             to->getName(toName);
 931             if (fromName == toName && from->getRawOffset() == to->getRawOffset()
 932                     && from->getDSTSavings() == to->getDSTSavings()) {
 933                 return getNextTransition(startTime, false, result);
 934             }
 935             result.setTime(startTime);
 936             result.adoptFrom(from->clone());
 937             result.adoptTo(to->clone());
 938             return TRUE;
 939         }
 940     }
 941     return FALSE;
 942 }
 943
 944 UBool
 945 OlsonTimeZone::getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const {
 946     UErrorCode status = U_ZERO_ERROR;
 947     checkTransitionRules(status);
 948     if (U_FAILURE(status)) {
 949         return FALSE;
 950     }
 951
 952     if (finalZone != NULL) {
 953         if (inclusive && base == firstFinalTZTransition->getTime()) {
 954             result = *firstFinalTZTransition;
 955             return TRUE;
 956         } else if (base > firstFinalTZTransition->getTime()) {
 957             if (finalZone->useDaylightTime()) {
 958                 //return finalZone->getPreviousTransition(base, inclusive, result);
 959                 return finalZoneWithStartYear->getPreviousTransition(base, inclusive, result);
 960             } else {
 961                 result = *firstFinalTZTransition;
 962                 return TRUE;
 963             }
 964         }
 965     }
 966
 967     if (historicRules != NULL) {
 968         // Find a historical transition
 969         int16_t ttidx = transitionCount() - 1;
 970         for (; ttidx >= firstTZTransitionIdx; ttidx--) {
 971             UDate t = (UDate)transitionTime(ttidx);
 972             if (base > t || (inclusive && base == t)) {
 973                 break;
 974             }
 975         }
 976         if (ttidx < firstTZTransitionIdx) {
 977             // No more transitions
 978             return FALSE;
 979         } else if (ttidx == firstTZTransitionIdx) {
 980             result = *firstTZTransition;
 981             return TRUE;
 982         } else {
 983             // Create a TimeZoneTransition
 984             TimeZoneRule *to = historicRules[typeMapData[ttidx]];
 985             TimeZoneRule *from = historicRules[typeMapData[ttidx-1]];
 986             UDate startTime = (UDate)transitionTime(ttidx);
 987
 988             // The transitions loaded from zoneinfo.res may contain non-transition data
 989             UnicodeString fromName, toName;
 990             from->getName(fromName);
 991             to->getName(toName);
 992             if (fromName == toName && from->getRawOffset() == to->getRawOffset()
 993                     && from->getDSTSavings() == to->getDSTSavings()) {
 994                 return getPreviousTransition(startTime, false, result);
 995             }
 996             result.setTime(startTime);
 997             result.adoptFrom(from->clone());
 998             result.adoptTo(to->clone());
 999             return TRUE;
1000         }
1001     }
1002     return FALSE;
1003 }
1004
1005 int32_t
1006 OlsonTimeZone::countTransitionRules(UErrorCode& status) const {
1007     if (U_FAILURE(status)) {
1008         return 0;
1009     }
1010     checkTransitionRules(status);
1011     if (U_FAILURE(status)) {
1012         return 0;
1013     }
1014
1015     int32_t count = 0;
1016     if (historicRules != NULL) {
1017         // historicRules may contain null entries when original zoneinfo data
1018         // includes non transition data.
1019         for (int32_t i = 0; i < historicRuleCount; i++) {
1020             if (historicRules[i] != NULL) {
1021                 count++;
1022             }
1023         }
1024     }
1025     if (finalZone != NULL) {
1026         if (finalZone->useDaylightTime()) {
1027             count += 2;
1028         } else {
1029             count++;
1030         }
1031     }
1032     return count;
1033 }
1034
1035 void
1036 OlsonTimeZone::getTimeZoneRules(const InitialTimeZoneRule*& initial,
1037                                 const TimeZoneRule* trsrules[],
1038                                 int32_t& trscount,
1039                                 UErrorCode& status) const {
1040     if (U_FAILURE(status)) {
1041         return;
1042     }
1043     checkTransitionRules(status);
1044     if (U_FAILURE(status)) {
1045         return;
1046     }
1047
1048     // Initial rule
1049     initial = initialRule;
1050
1051     // Transition rules
1052     int32_t cnt = 0;
1053     if (historicRules != NULL && trscount > cnt) {
1054         // historicRules may contain null entries when original zoneinfo data
1055         // includes non transition data.
1056         for (int32_t i = 0; i < historicRuleCount; i++) {
1057             if (historicRules[i] != NULL) {
1058                 trsrules[cnt++] = historicRules[i];
1059                 if (cnt >= trscount) {
1060                     break;
1061                 }
1062             }
1063         }
1064     }
1065     if (finalZoneWithStartYear != NULL && trscount > cnt) {
1066         const InitialTimeZoneRule *tmpini;
1067         int32_t tmpcnt = trscount - cnt;
1068         finalZoneWithStartYear->getTimeZoneRules(tmpini, &trsrules[cnt], tmpcnt, status);
1069         if (U_FAILURE(status)) {
1070             return;
1071         }
1072         cnt += tmpcnt;
1073     }
1074     // Set the result length
1075     trscount = cnt;
1076 }
1077
1078 U_NAMESPACE_END
1079
1080 #endif // !UCONFIG_NO_FORMATTING
1081
1082 //eof