]> git.saurik.com Git - apple/icu.git/blobdiff - icuSources/i18n/olsontz.cpp
ICU-64260.0.1.tar.gz
[apple/icu.git] / icuSources / i18n / olsontz.cpp
index 43adcb16bbc8b2fc1ca71520be28368fdeec60b9..7f9fe4370b494963eff34d8a72fc54ccbd11704e 100644 (file)
@@ -1,6 +1,8 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
 /*
 **********************************************************************
-* Copyright (c) 2003-2006, International Business Machines
+* Copyright (c) 2003-2013, International Business Machines
 * Corporation and others.  All Rights Reserved.
 **********************************************************************
 * Author: Alan Liu
@@ -9,6 +11,8 @@
 **********************************************************************
 */
 
+#include "utypeinfo.h"  // for 'typeid' to work
+
 #include "olsontz.h"
 
 #if !UCONFIG_NO_FORMATTING
 #include "gregoimp.h"
 #include "cmemory.h"
 #include "uassert.h"
+#include "uvector.h"
 #include <float.h> // DBL_MAX
+#include "uresimp.h"
+#include "zonemeta.h"
+#include "umutex.h"
 
 #ifdef U_DEBUG_TZ
 # include <stdio.h>
@@ -43,8 +51,32 @@ static void debug_tz_msg(const char *pat, ...)
 #define U_DEBUG_TZ_MSG(x)
 #endif
 
+static UBool arrayEqual(const void *a1, const void *a2, int32_t size) {
+    if (a1 == NULL && a2 == NULL) {
+        return TRUE;
+    }
+    if ((a1 != NULL && a2 == NULL) || (a1 == NULL && a2 != NULL)) {
+        return FALSE;
+    }
+    if (a1 == a2) {
+        return TRUE;
+    }
+
+    return (uprv_memcmp(a1, a2, size) == 0);
+}
+
 U_NAMESPACE_BEGIN
 
+#define kTRANS          "trans"
+#define kTRANSPRE32     "transPre32"
+#define kTRANSPOST32    "transPost32"
+#define kTYPEOFFSETS    "typeOffsets"
+#define kTYPEMAP        "typeMap"
+#define kLINKS          "links"
+#define kFINALRULE      "finalRule"
+#define kFINALRAW       "finalRaw"
+#define kFINALYEAR      "finalYear"
+
 #define SECONDS_PER_DAY (24*60*60)
 
 static const int32_t ZEROS[] = {0,0};
@@ -55,19 +87,27 @@ UOBJECT_DEFINE_RTTI_IMPLEMENTATION(OlsonTimeZone)
  * Default constructor.  Creates a time zone with an empty ID and
  * a fixed GMT offset of zero.
  */
-OlsonTimeZone::OlsonTimeZone() : finalYear(INT32_MAX), finalMillis(DBL_MAX), finalZone(0) {
+/*OlsonTimeZone::OlsonTimeZone() : finalYear(INT32_MAX), finalMillis(DBL_MAX), finalZone(0), transitionRulesInitialized(FALSE) {
+    clearTransitionRules();
     constructEmpty();
-}
+}*/
 
 /**
  * Construct a GMT+0 zone with no transitions.  This is done when a
  * constructor fails so the resultant object is well-behaved.
  */
 void OlsonTimeZone::constructEmpty() {
-    transitionCount = 0;
+    canonicalID = NULL;
+
+    transitionCountPre32 = transitionCount32 = transitionCountPost32 = 0;
+    transitionTimesPre32 = transitionTimes32 = transitionTimesPost32 = NULL;
+
+    typeMapData = NULL;
+
     typeCount = 1;
-    transitionTimes = typeOffsets = ZEROS;
-    typeData = (const uint8_t*) ZEROS;
+    typeOffsets = ZEROS;
+
+    finalZone = NULL;
 }
 
 /**
@@ -79,9 +119,11 @@ void OlsonTimeZone::constructEmpty() {
  */
 OlsonTimeZone::OlsonTimeZone(const UResourceBundle* top,
                              const UResourceBundle* res,
+                             const UnicodeString& tzid,
                              UErrorCode& ec) :
-  finalYear(INT32_MAX), finalMillis(DBL_MAX), finalZone(0)
+  BasicTimeZone(tzid), finalZone(NULL)
 {
+    clearTransitionRules();
     U_DEBUG_TZ_MSG(("OlsonTimeZone(%s)\n", ures_getKey((UResourceBundle*)res)));
     if ((top == NULL || res == NULL) && U_SUCCESS(ec)) {
         ec = U_ILLEGAL_ARGUMENT_ERROR;
@@ -91,117 +133,126 @@ OlsonTimeZone::OlsonTimeZone(const UResourceBundle* top,
         //        // TODO remove nonconst casts below when ures_* API is fixed
         //        setID(ures_getKey((UResourceBundle*) res)); // cast away const
 
-        // Size 1 is an alias TO another zone (int)
-        // HOWEVER, the caller should dereference this and never pass it in to us
-        // Size 3 is a purely historical zone (no final rules)
-        // Size 4 is like size 3, but with an alias list at the end
-        // Size 5 is a hybrid zone, with historical and final elements
-        // Size 6 is like size 5, but with an alias list at the end
-        int32_t size = ures_getSize(res);
-        if (size < 3 || size > 6) {
+        int32_t len;
+        StackUResourceBundle r;
+
+        // Pre-32bit second transitions
+        ures_getByKey(res, kTRANSPRE32, r.getAlias(), &ec);
+        transitionTimesPre32 = ures_getIntVector(r.getAlias(), &len, &ec);
+        transitionCountPre32 = static_cast<int16_t>(len >> 1);
+        if (ec == U_MISSING_RESOURCE_ERROR) {
+            // No pre-32bit transitions
+            transitionTimesPre32 = NULL;
+            transitionCountPre32 = 0;
+            ec = U_ZERO_ERROR;
+        } else if (U_SUCCESS(ec) && (len < 0 || len > 0x7FFF || (len & 1) != 0) /* len must be even */) {
             ec = U_INVALID_FORMAT_ERROR;
         }
 
-        // Transitions list may be empty
-        int32_t i;
-        UResourceBundle* r = ures_getByIndex(res, 0, NULL, &ec);
-        transitionTimes = ures_getIntVector(r, &i, &ec);
-        if ((i<0 || i>0x7FFF) && U_SUCCESS(ec)) {
+        // 32bit second transitions
+        ures_getByKey(res, kTRANS, r.getAlias(), &ec);
+        transitionTimes32 = ures_getIntVector(r.getAlias(), &len, &ec);
+        transitionCount32 = static_cast<int16_t>(len);
+        if (ec == U_MISSING_RESOURCE_ERROR) {
+            // No 32bit transitions
+            transitionTimes32 = NULL;
+            transitionCount32 = 0;
+            ec = U_ZERO_ERROR;
+        } else if (U_SUCCESS(ec) && (len < 0 || len > 0x7FFF)) {
             ec = U_INVALID_FORMAT_ERROR;
         }
-        transitionCount = (int16_t) i;
-        
-        // Type offsets list must be of even size, with size >= 2
-        r = ures_getByIndex(res, 1, r, &ec);
-        typeOffsets = ures_getIntVector(r, &i, &ec);
-        if ((i<2 || i>0x7FFE || ((i&1)!=0)) && U_SUCCESS(ec)) {
+
+        // Post-32bit second transitions
+        ures_getByKey(res, kTRANSPOST32, r.getAlias(), &ec);
+        transitionTimesPost32 = ures_getIntVector(r.getAlias(), &len, &ec);
+        transitionCountPost32 = static_cast<int16_t>(len >> 1);
+        if (ec == U_MISSING_RESOURCE_ERROR) {
+            // No pre-32bit transitions
+            transitionTimesPost32 = NULL;
+            transitionCountPost32 = 0;
+            ec = U_ZERO_ERROR;
+        } else if (U_SUCCESS(ec) && (len < 0 || len > 0x7FFF || (len & 1) != 0) /* len must be even */) {
             ec = U_INVALID_FORMAT_ERROR;
         }
-        typeCount = (int16_t) i >> 1;
 
-        // Type data must be of the same size as the transitions list        
-        r = ures_getByIndex(res, 2, r, &ec);
-        int32_t len;
-        typeData = ures_getBinary(r, &len, &ec);
-        ures_close(r);
-        if (len != transitionCount && U_SUCCESS(ec)) {
+        // Type offsets list must be of even size, with size >= 2
+        ures_getByKey(res, kTYPEOFFSETS, r.getAlias(), &ec);
+        typeOffsets = ures_getIntVector(r.getAlias(), &len, &ec);
+        if (U_SUCCESS(ec) && (len < 2 || len > 0x7FFE || (len & 1) != 0)) {
             ec = U_INVALID_FORMAT_ERROR;
         }
+        typeCount = (int16_t) len >> 1;
 
-#if defined (U_DEBUG_TZ)
-        U_DEBUG_TZ_MSG(("OlsonTimeZone(%s) - size = %d, typecount %d transitioncount %d - err %s\n", ures_getKey((UResourceBundle*)res), size, typeCount,  transitionCount, u_errorName(ec)));
-        if(U_SUCCESS(ec)) {
-          int32_t jj;
-          for(jj=0;jj<transitionCount;jj++) {
-            int32_t year, month, dom, dow;
-            double millis=0;
-            double days = Math::floorDivide(((double)transitionTimes[jj])*1000.0, (double)U_MILLIS_PER_DAY, millis);
-            
-            Grego::dayToFields(days, year, month, dom, dow);
-            U_DEBUG_TZ_MSG(("   Transition %d:  time %d (%04d.%02d.%02d+%.1fh), typedata%d\n", jj, transitionTimes[jj],
-                            year, month+1, dom, (millis/kOneHour), typeData[jj]));
-//            U_DEBUG_TZ_MSG(("     offset%d\n", typeOffsets[jj]));
-            int16_t f = jj;
-            f <<= 1;
-            U_DEBUG_TZ_MSG(("     offsets[%d+%d]=(%d+%d)=(%d==%d)\n", (int)f,(int)f+1,(int)typeOffsets[f],(int)typeOffsets[f+1],(int)zoneOffset(jj),
-                (int)typeOffsets[f]+(int)typeOffsets[f+1]));
-          }
+        // Type map data must be of the same size as the transition count
+        typeMapData =  NULL;
+        if (transitionCount() > 0) {
+            ures_getByKey(res, kTYPEMAP, r.getAlias(), &ec);
+            typeMapData = ures_getBinary(r.getAlias(), &len, &ec);
+            if (ec == U_MISSING_RESOURCE_ERROR) {
+                // no type mapping data
+                ec = U_INVALID_FORMAT_ERROR;
+            } else if (U_SUCCESS(ec) && len != transitionCount()) {
+                ec = U_INVALID_FORMAT_ERROR;
+            }
         }
-#endif
 
         // Process final rule and data, if any
-        if (size >= 5) {
-            int32_t ruleidLen = 0;
-            const UChar* idUStr = ures_getStringByIndex(res, 3, &ruleidLen, &ec);
-            UnicodeString ruleid(TRUE, idUStr, ruleidLen);
-            r = ures_getByIndex(res, 4, NULL, &ec);
-            const int32_t* data = ures_getIntVector(r, &len, &ec);
-#if defined U_DEBUG_TZ
-            const char *rKey = ures_getKey(r);
-            const char *zKey = ures_getKey((UResourceBundle*)res);
-#endif
-            ures_close(r);
-            if (U_SUCCESS(ec)) {
-                if (data != 0 && len == 2) {
-                    int32_t rawOffset = data[0] * U_MILLIS_PER_SECOND;
-                    // Subtract one from the actual final year; we
-                    // actually store final year - 1, and compare
-                    // using > rather than >=.  This allows us to use
-                    // INT32_MAX as an exclusive upper limit for all
-                    // years, including INT32_MAX.
-                    U_ASSERT(data[1] > INT32_MIN);
-                    finalYear = data[1] - 1;
-                    // Also compute the millis for Jan 1, 0:00 GMT of the
-                    // finalYear.  This reduces runtime computations.
-                    finalMillis = Grego::fieldsToDay(data[1], 0, 1) * U_MILLIS_PER_DAY;
-                    U_DEBUG_TZ_MSG(("zone%s|%s: {%d,%d}, finalYear%d, finalMillis%.1lf\n",
-                                    zKey,rKey, data[0], data[1], finalYear, finalMillis));
-                    r = TimeZone::loadRule(top, ruleid, NULL, ec);
-                    if (U_SUCCESS(ec)) {
-                        // 3, 1, -1, 7200, 0, 9, -31, -1, 7200, 0, 3600
-                        data = ures_getIntVector(r, &len, &ec);
-                        if (U_SUCCESS(ec) && len == 11) {
-                            UnicodeString emptyStr;
-                            U_DEBUG_TZ_MSG(("zone%s, rule%s: {%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d}\n", zKey, ures_getKey(r), 
-                                          data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7], data[8], data[9], data[10]));
-                            finalZone = new SimpleTimeZone(rawOffset, emptyStr,
-                                (int8_t)data[0], (int8_t)data[1], (int8_t)data[2],
-                                data[3] * U_MILLIS_PER_SECOND,
-                                (SimpleTimeZone::TimeMode) data[4],
-                                (int8_t)data[5], (int8_t)data[6], (int8_t)data[7],
-                                data[8] * U_MILLIS_PER_SECOND,
-                                (SimpleTimeZone::TimeMode) data[9],
-                                data[10] * U_MILLIS_PER_SECOND, ec);
-                        } else {
-                            ec = U_INVALID_FORMAT_ERROR;
-                        }
-                    }
-                    ures_close(r);
+        const UChar *ruleIdUStr = ures_getStringByKey(res, kFINALRULE, &len, &ec);
+        ures_getByKey(res, kFINALRAW, r.getAlias(), &ec);
+        int32_t ruleRaw = ures_getInt(r.getAlias(), &ec);
+        ures_getByKey(res, kFINALYEAR, r.getAlias(), &ec);
+        int32_t ruleYear = ures_getInt(r.getAlias(), &ec);
+        if (U_SUCCESS(ec)) {
+            UnicodeString ruleID(TRUE, ruleIdUStr, len);
+            UResourceBundle *rule = TimeZone::loadRule(top, ruleID, NULL, ec);
+            const int32_t *ruleData = ures_getIntVector(rule, &len, &ec); 
+            if (U_SUCCESS(ec) && len == 11) {
+                UnicodeString emptyStr;
+                finalZone = new SimpleTimeZone(
+                    ruleRaw * U_MILLIS_PER_SECOND,
+                    emptyStr,
+                    (int8_t)ruleData[0], (int8_t)ruleData[1], (int8_t)ruleData[2],
+                    ruleData[3] * U_MILLIS_PER_SECOND,
+                    (SimpleTimeZone::TimeMode) ruleData[4],
+                    (int8_t)ruleData[5], (int8_t)ruleData[6], (int8_t)ruleData[7],
+                    ruleData[8] * U_MILLIS_PER_SECOND,
+                    (SimpleTimeZone::TimeMode) ruleData[9],
+                    ruleData[10] * U_MILLIS_PER_SECOND, ec);
+                if (finalZone == NULL) {
+                    ec = U_MEMORY_ALLOCATION_ERROR;
                 } else {
-                    ec = U_INVALID_FORMAT_ERROR;
+                    finalStartYear = ruleYear;
+
+                    // Note: Setting finalStartYear to the finalZone is problematic.  When a date is around
+                    // year boundary, SimpleTimeZone may return false result when DST is observed at the 
+                    // beginning of year.  We could apply safe margin (day or two), but when one of recurrent
+                    // rules falls around year boundary, it could return false result.  Without setting the
+                    // start year, finalZone works fine around the year boundary of the start year.
+
+                    // finalZone->setStartYear(finalStartYear);
+
+
+                    // Compute the millis for Jan 1, 0:00 GMT of the finalYear
+
+                    // Note: finalStartMillis is used for detecting either if
+                    // historic transition data or finalZone to be used.  In an
+                    // extreme edge case - for example, two transitions fall into
+                    // small windows of time around the year boundary, this may
+                    // result incorrect offset computation.  But I think it will
+                    // never happen practically.  Yoshito - Feb 20, 2010
+                    finalStartMillis = Grego::fieldsToDay(finalStartYear, 0, 1) * U_MILLIS_PER_DAY;
                 }
+            } else {
+                ec = U_INVALID_FORMAT_ERROR;
             }
+            ures_close(rule);
+        } else if (ec == U_MISSING_RESOURCE_ERROR) {
+            // No final zone
+            ec = U_ZERO_ERROR;
         }
+
+        // initialize canonical ID
+        canonicalID = ZoneMeta::getCanonicalCLDRID(tzid, ec);
     }
 
     if (U_FAILURE(ec)) {
@@ -213,7 +264,7 @@ OlsonTimeZone::OlsonTimeZone(const UResourceBundle* top,
  * Copy constructor
  */
 OlsonTimeZone::OlsonTimeZone(const OlsonTimeZone& other) :
-    TimeZone(other), finalZone(0) {
+    BasicTimeZone(other), finalZone(0) {
     *this = other;
 }
 
@@ -221,16 +272,29 @@ OlsonTimeZone::OlsonTimeZone(const OlsonTimeZone& other) :
  * Assignment operator
  */
 OlsonTimeZone& OlsonTimeZone::operator=(const OlsonTimeZone& other) {
-    transitionCount = other.transitionCount;
+    canonicalID = other.canonicalID;
+
+    transitionTimesPre32 = other.transitionTimesPre32;
+    transitionTimes32 = other.transitionTimes32;
+    transitionTimesPost32 = other.transitionTimesPost32;
+
+    transitionCountPre32 = other.transitionCountPre32;
+    transitionCount32 = other.transitionCount32;
+    transitionCountPost32 = other.transitionCountPost32;
+
     typeCount = other.typeCount;
-    transitionTimes = other.transitionTimes;
     typeOffsets = other.typeOffsets;
-    typeData = other.typeData;
-    finalYear = other.finalYear;
-    finalMillis = other.finalMillis;
+    typeMapData = other.typeMapData;
+
     delete finalZone;
     finalZone = (other.finalZone != 0) ?
         (SimpleTimeZone*) other.finalZone->clone() : 0;
+
+    finalStartYear = other.finalStartYear;
+    finalStartMillis = other.finalStartMillis;
+
+    clearTransitionRules();
+
     return *this;
 }
 
@@ -238,6 +302,7 @@ OlsonTimeZone& OlsonTimeZone::operator=(const OlsonTimeZone& other) {
  * Destructor
  */
 OlsonTimeZone::~OlsonTimeZone() {
+    deleteTransitionRules();
     delete finalZone;
 }
 
@@ -245,29 +310,10 @@ OlsonTimeZone::~OlsonTimeZone() {
  * Returns true if the two TimeZone objects are equal.
  */
 UBool OlsonTimeZone::operator==(const TimeZone& other) const {
-    const OlsonTimeZone* z = (const OlsonTimeZone*) &other;
-
-    return TimeZone::operator==(other) &&
-        // [sic] pointer comparison: typeData points into
-        // memory-mapped or DLL space, so if two zones have the same
-        // pointer, they are equal.
-        (typeData == z->typeData ||
-         // If the pointers are not equal, the zones may still
-         // be equal if their rules and transitions are equal
-         (finalYear == z->finalYear &&
-          // Don't compare finalMillis; if finalYear is ==, so is finalMillis
-          ((finalZone == 0 && z->finalZone == 0) ||
-           (finalZone != 0 && z->finalZone != 0 &&
-            *finalZone == *z->finalZone)) &&
-          transitionCount == z->transitionCount &&
-          typeCount == z->typeCount &&
-          uprv_memcmp(transitionTimes, z->transitionTimes,
-                      sizeof(transitionTimes[0]) * transitionCount) == 0 &&
-          uprv_memcmp(typeOffsets, z->typeOffsets,
-                      (sizeof(typeOffsets[0]) * typeCount) << 1) == 0 &&
-          uprv_memcmp(typeData, z->typeData,
-                      (sizeof(typeData[0]) * typeCount)) == 0
-          ));
+    return ((this == &other) ||
+            (typeid(*this) == typeid(other) &&
+            TimeZone::operator==(other) &&
+            hasSameRules(other)));
 }
 
 /**
@@ -325,17 +371,16 @@ int32_t OlsonTimeZone::getOffset(uint8_t era, int32_t year, int32_t month,
         year = -year;
     }
 
-    if (year > finalYear) { // [sic] >, not >=; see above
-        U_ASSERT(finalZone != 0);
+    if (finalZone != NULL && year >= finalStartYear) {
         return finalZone->getOffset(era, year, month, dom, dow,
                                     millis, monthLength, ec);
     }
 
-    // Compute local epoch seconds from input fields
-    double time = Grego::fieldsToDay(year, month, dom) * SECONDS_PER_DAY +
-        uprv_floor(millis / (double) U_MILLIS_PER_SECOND);
-
-    return zoneOffset(findTransition(time, TRUE)) * U_MILLIS_PER_SECOND;
+    // Compute local epoch millis from input fields
+    UDate date = (UDate)(Grego::fieldsToDay(year, month, dom) * U_MILLIS_PER_DAY + millis);
+    int32_t rawoff, dstoff;
+    getHistoricalOffset(date, TRUE, kDaylight, kStandard, rawoff, dstoff);
+    return rawoff + dstoff;
 }
 
 /**
@@ -346,40 +391,27 @@ void OlsonTimeZone::getOffset(UDate date, UBool local, int32_t& rawoff,
     if (U_FAILURE(ec)) {
         return;
     }
+    if (finalZone != NULL && date >= finalStartMillis) {
+        finalZone->getOffset(date, local, rawoff, dstoff, ec);
+    } else {
+        getHistoricalOffset(date, local, kFormer, kLatter, rawoff, dstoff);
+    }
+}
 
-    // The check against finalMillis will suffice most of the time, except
-    // for the case in which finalMillis == DBL_MAX, date == DBL_MAX,
-    // and finalZone == 0.  For this case we add "&& finalZone != 0".
-    if (date >= finalMillis && finalZone != 0) {
-        int32_t year, month, dom, dow;
-        double millis;
-        double days = Math::floorDivide(date, (double)U_MILLIS_PER_DAY, millis);
-        
-        Grego::dayToFields(days, year, month, dom, dow);
-
-        rawoff = finalZone->getRawOffset();
-
-        if (!local) {
-            // Adjust from GMT to local
-            date += rawoff;
-            double days2 = Math::floorDivide(date, (double)U_MILLIS_PER_DAY, millis);
-            if (days2 != days) {
-                Grego::dayToFields(days2, year, month, dom, dow);
-            }
-        }
-
-        dstoff = finalZone->getOffset(
-            GregorianCalendar::AD, year, month,
-            dom, (uint8_t) dow, (int32_t) millis, ec) - rawoff;
+void
+OlsonTimeZone::getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt,
+                                  int32_t& rawoff, int32_t& dstoff, UErrorCode& ec) const {
+    if (U_FAILURE(ec)) {
         return;
     }
-
-    double secs = uprv_floor(date / U_MILLIS_PER_SECOND);
-    int16_t i = findTransition(secs, local);
-    rawoff = rawOffset(i) * U_MILLIS_PER_SECOND;
-    dstoff = dstOffset(i) * U_MILLIS_PER_SECOND;
+    if (finalZone != NULL && date >= finalStartMillis) {
+        finalZone->getOffsetFromLocal(date, nonExistingTimeOpt, duplicatedTimeOpt, rawoff, dstoff, ec);
+    } else {
+        getHistoricalOffset(date, TRUE, nonExistingTimeOpt, duplicatedTimeOpt, rawoff, dstoff);
+    }
 }
 
+
 /**
  * TimeZone API.
  */
@@ -405,91 +437,119 @@ int32_t OlsonTimeZone::getRawOffset() const {
 void printTime(double ms) {
             int32_t year, month, dom, dow;
             double millis=0;
-            double days = Math::floorDivide(((double)ms), (double)U_MILLIS_PER_DAY, millis);
+            double days = ClockMath::floorDivide(((double)ms), (double)U_MILLIS_PER_DAY, millis);
             
             Grego::dayToFields(days, year, month, dom, dow);
-            U_DEBUG_TZ_MSG(("   findTransition:  time %.1f (%04d.%02d.%02d+%.1fh)\n", ms,
+            U_DEBUG_TZ_MSG(("   getHistoricalOffset:  time %.1f (%04d.%02d.%02d+%.1fh)\n", ms,
                             year, month+1, dom, (millis/kOneHour)));
     }
 #endif
 
-/**
- * Find the smallest i (in 0..transitionCount-1) such that time >=
- * transition(i), where transition(i) is either the GMT or the local
- * transition time, as specified by `local'.
- * @param time epoch seconds, either GMT or local wall
- * @param local if TRUE, `time' is in local wall units, otherwise it
- * is GMT
- * @return an index i, where 0 <= i < transitionCount, and
- * transition(i) <= time < transition(i+1), or i == 0 if
- * transitionCount == 0 or time < transition(0).
- */
-int16_t OlsonTimeZone::findTransition(double time, UBool local) const {
-    int16_t i = 0;
-    U_DEBUG_TZ_MSG(("findTransition(%.1f, %s)\n", time, local?"T":"F"));
-#if defined U_DEBUG_TZ
-        printTime(time*1000.0);
-#endif
-    
-    if (transitionCount != 0) {
-        // Linear search from the end is the fastest approach, since
-        // most lookups will happen at/near the end.
-        for (i = transitionCount - 1; i > 0; --i) {
-            int32_t transition = transitionTimes[i];
-            if (local) {
-                int32_t zoneOffsetPrev = zoneOffset(typeData[i-1]);
-                int32_t zoneOffsetCurr = zoneOffset(typeData[i]);
-                
-                // use the lowest offset ( == standard time ). as per tzregts.cpp which says:
-
-                    /**
-                     * @bug 4084933
-                     * The expected behavior of TimeZone around the boundaries is:
-                     * (Assume transition time of 2:00 AM)
-                     *    day of onset 1:59 AM STD  = display name 1:59 AM ST
-                     *                 2:00 AM STD  = display name 3:00 AM DT
-                     *    day of end   0:59 AM STD  = display name 1:59 AM DT
-                     *                 1:00 AM STD  = display name 1:00 AM ST
-                     */
-                if(zoneOffsetPrev<zoneOffsetCurr) {
-                    transition += zoneOffsetPrev;
-                } else {
-                    transition += zoneOffsetCurr;
-                }
-            }
-            if (time >= transition) {
-                U_DEBUG_TZ_MSG(("Found@%d: time=%.1f, localtransition=%d (orig %d) dz %d\n", i, time, transition, transitionTimes[i],
-                    zoneOffset(typeData[i-1])));
-#if defined U_DEBUG_TZ
-        printTime(transition*1000.0);
-        printTime(transitionTimes[i]*1000.0);
-#endif
-                break;
-            } else {
-                U_DEBUG_TZ_MSG(("miss@%d: time=%.1f, localtransition=%d (orig %d) dz %d\n", i, time, transition, transitionTimes[i],
-                    zoneOffset(typeData[i-1])));
+int64_t
+OlsonTimeZone::transitionTimeInSeconds(int16_t transIdx) const {
+    U_ASSERT(transIdx >= 0 && transIdx < transitionCount()); 
+
+    if (transIdx < transitionCountPre32) {
+        return (((int64_t)((uint32_t)transitionTimesPre32[transIdx << 1])) << 32)
+            | ((int64_t)((uint32_t)transitionTimesPre32[(transIdx << 1) + 1]));
+    }
+
+    transIdx -= transitionCountPre32;
+    if (transIdx < transitionCount32) {
+        return (int64_t)transitionTimes32[transIdx];
+    }
+
+    transIdx -= transitionCount32;
+    return (((int64_t)((uint32_t)transitionTimesPost32[transIdx << 1])) << 32)
+        | ((int64_t)((uint32_t)transitionTimesPost32[(transIdx << 1) + 1]));
+}
+
+// Maximum absolute offset in seconds (86400 seconds = 1 day)
+// getHistoricalOffset uses this constant as safety margin of
+// quick zone transition checking.
+#define MAX_OFFSET_SECONDS 86400
+
+void
+OlsonTimeZone::getHistoricalOffset(UDate date, UBool local,
+                                   int32_t NonExistingTimeOpt, int32_t DuplicatedTimeOpt,
+                                   int32_t& rawoff, int32_t& dstoff) const {
+    U_DEBUG_TZ_MSG(("getHistoricalOffset(%.1f, %s, %d, %d, raw, dst)\n",
+        date, local?"T":"F", NonExistingTimeOpt, DuplicatedTimeOpt));
 #if defined U_DEBUG_TZ
-        printTime(transition*1000.0);
-        printTime(transitionTimes[i]*1000.0);
+        printTime(date*1000.0);
 #endif
-            }
-        }
+    int16_t transCount = transitionCount();
 
-        U_ASSERT(i>=0 && i<transitionCount);
+    if (transCount > 0) {
+        double sec = uprv_floor(date / U_MILLIS_PER_SECOND);
+        if (!local && sec < transitionTimeInSeconds(0)) {
+            // Before the first transition time
+            rawoff = initialRawOffset() * U_MILLIS_PER_SECOND;
+            dstoff = initialDstOffset() * U_MILLIS_PER_SECOND;
+        } else {
+            // Linear search from the end is the fastest approach, since
+            // most lookups will happen at/near the end.
+            int16_t transIdx;
+            for (transIdx = transCount - 1; transIdx >= 0; transIdx--) {
+                int64_t transition = transitionTimeInSeconds(transIdx);
 
-        // Check invariants for GMT times; if these pass for GMT times
-        // the local logic should be working too.
-        U_ASSERT(local || time < transitionTimes[0] || time >= transitionTimes[i]);
-        U_ASSERT(local || i == transitionCount-1 || time < transitionTimes[i+1]);
+                if (local && (sec >= (transition - MAX_OFFSET_SECONDS))) {
+                    int32_t offsetBefore = zoneOffsetAt(transIdx - 1);
+                    UBool dstBefore = dstOffsetAt(transIdx - 1) != 0;
 
-        U_DEBUG_TZ_MSG(("findTransition(%.1f, %s)= trans %d\n", time, local?"T":"F", i));
-        i = typeData[i];
-    }
+                    int32_t offsetAfter = zoneOffsetAt(transIdx);
+                    UBool dstAfter = dstOffsetAt(transIdx) != 0;
 
-    U_ASSERT(i>=0 && i<typeCount);
-    
-    U_DEBUG_TZ_MSG(("findTransition(%.1f, %s)=%d, offset %d\n", time, local?"T":"F", i, zoneOffset(i)));
-    return i;
+                    UBool dstToStd = dstBefore && !dstAfter;
+                    UBool stdToDst = !dstBefore && dstAfter;
+                    
+                    if (offsetAfter - offsetBefore >= 0) {
+                        // Positive transition, which makes a non-existing local time range
+                        if (((NonExistingTimeOpt & kStdDstMask) == kStandard && dstToStd)
+                                || ((NonExistingTimeOpt & kStdDstMask) == kDaylight && stdToDst)) {
+                            transition += offsetBefore;
+                        } else if (((NonExistingTimeOpt & kStdDstMask) == kStandard && stdToDst)
+                                || ((NonExistingTimeOpt & kStdDstMask) == kDaylight && dstToStd)) {
+                            transition += offsetAfter;
+                        } else if ((NonExistingTimeOpt & kFormerLatterMask) == kLatter) {
+                            transition += offsetBefore;
+                        } else {
+                            // Interprets the time with rule before the transition,
+                            // default for non-existing time range
+                            transition += offsetAfter;
+                        }
+                    } else {
+                        // Negative transition, which makes a duplicated local time range
+                        if (((DuplicatedTimeOpt & kStdDstMask) == kStandard && dstToStd)
+                                || ((DuplicatedTimeOpt & kStdDstMask) == kDaylight && stdToDst)) {
+                            transition += offsetAfter;
+                        } else if (((DuplicatedTimeOpt & kStdDstMask) == kStandard && stdToDst)
+                                || ((DuplicatedTimeOpt & kStdDstMask) == kDaylight && dstToStd)) {
+                            transition += offsetBefore;
+                        } else if ((DuplicatedTimeOpt & kFormerLatterMask) == kFormer) {
+                            transition += offsetBefore;
+                        } else {
+                            // Interprets the time with rule after the transition,
+                            // default for duplicated local time range
+                            transition += offsetAfter;
+                        }
+                    }
+                }
+                if (sec >= transition) {
+                    break;
+                }
+            }
+            // transIdx could be -1 when local=true
+            rawoff = rawOffsetAt(transIdx) * U_MILLIS_PER_SECOND;
+            dstoff = dstOffsetAt(transIdx) * U_MILLIS_PER_SECOND;
+        }
+    } else {
+        // No transitions, single pair of offsets only
+        rawoff = initialRawOffset() * U_MILLIS_PER_SECOND;
+        dstoff = initialDstOffset() * U_MILLIS_PER_SECOND;
+    }
+    U_DEBUG_TZ_MSG(("getHistoricalOffset(%.1f, %s, %d, %d, raw, dst) - raw=%d, dst=%d\n",
+        date, local?"T":"F", NonExistingTimeOpt, DuplicatedTimeOpt, rawoff, dstoff));
 }
 
 /**
@@ -502,29 +562,27 @@ UBool OlsonTimeZone::useDaylightTime() const {
     // DST is in use in the current year (at any point in the year)
     // and returns TRUE if so.
 
-    int32_t days = (int32_t)Math::floorDivide(uprv_getUTCtime(), (double)U_MILLIS_PER_DAY); // epoch days
-
-    int32_t year, month, dom, dow;
-    
-    Grego::dayToFields(days, year, month, dom, dow);
-
-    if (year > finalYear) { // [sic] >, not >=; see above
-        U_ASSERT(finalZone != 0 && finalZone->useDaylightTime());
-        return TRUE;
+    UDate current = uprv_getUTCtime();
+    if (finalZone != NULL && current >= finalStartMillis) {
+        return finalZone->useDaylightTime();
     }
 
+    int32_t year, month, dom, dow, doy, mid;
+    Grego::timeToFields(current, year, month, dom, dow, doy, mid);
+
     // Find start of this year, and start of next year
-    int32_t start = (int32_t) Grego::fieldsToDay(year, 0, 1) * SECONDS_PER_DAY;    
-    int32_t limit = (int32_t) Grego::fieldsToDay(year+1, 0, 1) * SECONDS_PER_DAY;    
+    double start = Grego::fieldsToDay(year, 0, 1) * SECONDS_PER_DAY;
+    double limit = Grego::fieldsToDay(year+1, 0, 1) * SECONDS_PER_DAY;
 
     // Return TRUE if DST is observed at any time during the current
     // year.
-    for (int16_t i=0; i<transitionCount; ++i) {
-        if (transitionTimes[i] >= limit) {
+    for (int16_t i = 0; i < transitionCount(); ++i) {
+        double transition = (double)transitionTimeInSeconds(i);
+        if (transition >= limit) {
             break;
         }
-        if (transitionTimes[i] >= start &&
-            dstOffset(typeData[i]) != 0) {
+        if ((transition >= start && dstOffsetAt(i) != 0)
+                || (transition > start && dstOffsetAt(i - 1) != 0)) {
             return TRUE;
         }
     }
@@ -532,7 +590,7 @@ UBool OlsonTimeZone::useDaylightTime() const {
 }
 int32_t 
 OlsonTimeZone::getDSTSavings() const{
-    if(finalZone!=NULL){
+    if (finalZone != NULL){
         return finalZone->getDSTSavings();
     }
     return TimeZone::getDSTSavings();
@@ -546,6 +604,476 @@ UBool OlsonTimeZone::inDaylightTime(UDate date, UErrorCode& ec) const {
     return dst != 0;
 }
 
+UBool
+OlsonTimeZone::hasSameRules(const TimeZone &other) const {
+    if (this == &other) {
+        return TRUE;
+    }
+    const OlsonTimeZone* z = dynamic_cast<const OlsonTimeZone*>(&other);
+    if (z == NULL) {
+        return FALSE;
+    }
+
+    // [sic] pointer comparison: typeMapData points into
+    // memory-mapped or DLL space, so if two zones have the same
+    // pointer, they are equal.
+    if (typeMapData == z->typeMapData) {
+        return TRUE;
+    }
+    
+    // If the pointers are not equal, the zones may still
+    // be equal if their rules and transitions are equal
+    if ((finalZone == NULL && z->finalZone != NULL)
+        || (finalZone != NULL && z->finalZone == NULL)
+        || (finalZone != NULL && z->finalZone != NULL && *finalZone != *z->finalZone)) {
+        return FALSE;
+    }
+
+    if (finalZone != NULL) {
+        if (finalStartYear != z->finalStartYear || finalStartMillis != z->finalStartMillis) {
+            return FALSE;
+        }
+    }
+    if (typeCount != z->typeCount
+        || transitionCountPre32 != z->transitionCountPre32
+        || transitionCount32 != z->transitionCount32
+        || transitionCountPost32 != z->transitionCountPost32) {
+        return FALSE;
+    }
+
+    return
+        arrayEqual(transitionTimesPre32, z->transitionTimesPre32, sizeof(transitionTimesPre32[0]) * transitionCountPre32 << 1)
+        && arrayEqual(transitionTimes32, z->transitionTimes32, sizeof(transitionTimes32[0]) * transitionCount32)
+        && arrayEqual(transitionTimesPost32, z->transitionTimesPost32, sizeof(transitionTimesPost32[0]) * transitionCountPost32 << 1)
+        && arrayEqual(typeOffsets, z->typeOffsets, sizeof(typeOffsets[0]) * typeCount << 1)
+        && arrayEqual(typeMapData, z->typeMapData, sizeof(typeMapData[0]) * transitionCount());
+}
+
+void
+OlsonTimeZone::clearTransitionRules(void) {
+    initialRule = NULL;
+    firstTZTransition = NULL;
+    firstFinalTZTransition = NULL;
+    historicRules = NULL;
+    historicRuleCount = 0;
+    finalZoneWithStartYear = NULL;
+    firstTZTransitionIdx = 0;
+    transitionRulesInitOnce.reset();
+}
+
+void
+OlsonTimeZone::deleteTransitionRules(void) {
+    if (initialRule != NULL) {
+        delete initialRule;
+    }
+    if (firstTZTransition != NULL) {
+        delete firstTZTransition;
+    }
+    if (firstFinalTZTransition != NULL) {
+        delete firstFinalTZTransition;
+    }
+    if (finalZoneWithStartYear != NULL) {
+        delete finalZoneWithStartYear;
+    }
+    if (historicRules != NULL) {
+        for (int i = 0; i < historicRuleCount; i++) {
+            if (historicRules[i] != NULL) {
+                delete historicRules[i];
+            }
+        }
+        uprv_free(historicRules);
+    }
+    clearTransitionRules();
+}
+
+/*
+ * Lazy transition rules initializer
+ */
+
+static void U_CALLCONV initRules(OlsonTimeZone *This, UErrorCode &status) {
+    This->initTransitionRules(status);
+}
+    
+void
+OlsonTimeZone::checkTransitionRules(UErrorCode& status) const {
+    OlsonTimeZone *ncThis = const_cast<OlsonTimeZone *>(this);
+    umtx_initOnce(ncThis->transitionRulesInitOnce, &initRules, ncThis, status);
+}
+
+void
+OlsonTimeZone::initTransitionRules(UErrorCode& status) {
+    if(U_FAILURE(status)) {
+        return;
+    }
+    deleteTransitionRules();
+    UnicodeString tzid;
+    getID(tzid);
+
+    UnicodeString stdName = tzid + UNICODE_STRING_SIMPLE("(STD)");
+    UnicodeString dstName = tzid + UNICODE_STRING_SIMPLE("(DST)");
+
+    int32_t raw, dst;
+
+    // Create initial rule
+    raw = initialRawOffset() * U_MILLIS_PER_SECOND;
+    dst = initialDstOffset() * U_MILLIS_PER_SECOND;
+    initialRule = new InitialTimeZoneRule((dst == 0 ? stdName : dstName), raw, dst);
+    // Check to make sure initialRule was created
+    if (initialRule == NULL) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+        deleteTransitionRules();
+        return;
+    }
+
+    int32_t transCount = transitionCount();
+    if (transCount > 0) {
+        int16_t transitionIdx, typeIdx;
+
+        // We probably no longer need to check the first "real" transition
+        // here, because the new tzcode remove such transitions already.
+        // For now, keeping this code for just in case. Feb 19, 2010 Yoshito
+        firstTZTransitionIdx = 0;
+        for (transitionIdx = 0; transitionIdx < transCount; transitionIdx++) {
+            if (typeMapData[transitionIdx] != 0) { // type 0 is the initial type
+                break;
+            }
+            firstTZTransitionIdx++;
+        }
+        if (transitionIdx == transCount) {
+            // Actually no transitions...
+        } else {
+            // Build historic rule array
+            UDate* times = (UDate*)uprv_malloc(sizeof(UDate)*transCount); /* large enough to store all transition times */
+            if (times == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+            }
+            for (typeIdx = 0; typeIdx < typeCount; typeIdx++) {
+                // Gather all start times for each pair of offsets
+                int32_t nTimes = 0;
+                for (transitionIdx = firstTZTransitionIdx; transitionIdx < transCount; transitionIdx++) {
+                    if (typeIdx == (int16_t)typeMapData[transitionIdx]) {
+                        UDate tt = (UDate)transitionTime(transitionIdx);
+                        if (finalZone == NULL || tt <= finalStartMillis) {
+                            // Exclude transitions after finalMillis
+                            times[nTimes++] = tt;
+                        }
+                    }
+                }
+                if (nTimes > 0) {
+                    // Create a TimeArrayTimeZoneRule
+                    raw = typeOffsets[typeIdx << 1] * U_MILLIS_PER_SECOND;
+                    dst = typeOffsets[(typeIdx << 1) + 1] * U_MILLIS_PER_SECOND;
+                    if (historicRules == NULL) {
+                        historicRuleCount = typeCount;
+                        historicRules = (TimeArrayTimeZoneRule**)uprv_malloc(sizeof(TimeArrayTimeZoneRule*)*historicRuleCount);
+                        if (historicRules == NULL) {
+                            status = U_MEMORY_ALLOCATION_ERROR;
+                            deleteTransitionRules();
+                            uprv_free(times);
+                            return;
+                        }
+                        for (int i = 0; i < historicRuleCount; i++) {
+                            // Initialize TimeArrayTimeZoneRule pointers as NULL
+                            historicRules[i] = NULL;
+                        }
+                    }
+                    historicRules[typeIdx] = new TimeArrayTimeZoneRule((dst == 0 ? stdName : dstName),
+                        raw, dst, times, nTimes, DateTimeRule::UTC_TIME);
+                    // Check for memory allocation error
+                    if (historicRules[typeIdx] == NULL) {
+                        status = U_MEMORY_ALLOCATION_ERROR;
+                        deleteTransitionRules();
+                        return;
+                    }
+                }
+            }
+            uprv_free(times);
+
+            // Create initial transition
+            typeIdx = (int16_t)typeMapData[firstTZTransitionIdx];
+            firstTZTransition = new TimeZoneTransition((UDate)transitionTime(firstTZTransitionIdx),
+                    *initialRule, *historicRules[typeIdx]);
+            // Check to make sure firstTZTransition was created.
+            if (firstTZTransition == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+            }
+        }
+    }
+    if (finalZone != NULL) {
+        // Get the first occurence of final rule starts
+        UDate startTime = (UDate)finalStartMillis;
+        TimeZoneRule *firstFinalRule = NULL;
+
+        if (finalZone->useDaylightTime()) {
+            /*
+             * Note: When an OlsonTimeZone is constructed, we should set the final year
+             * as the start year of finalZone.  However, the bounday condition used for
+             * getting offset from finalZone has some problems.
+             * For now, we do not set the valid start year when the construction time
+             * and create a clone and set the start year when extracting rules.
+             */
+            finalZoneWithStartYear = (SimpleTimeZone*)finalZone->clone();
+            // Check to make sure finalZone was actually cloned.
+            if (finalZoneWithStartYear == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+            }
+            finalZoneWithStartYear->setStartYear(finalStartYear);
+
+            TimeZoneTransition tzt;
+            finalZoneWithStartYear->getNextTransition(startTime, false, tzt);
+            firstFinalRule  = tzt.getTo()->clone();
+            // Check to make sure firstFinalRule received proper clone.
+            if (firstFinalRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+            }
+            startTime = tzt.getTime();
+        } else {
+            // final rule with no transitions
+            finalZoneWithStartYear = (SimpleTimeZone*)finalZone->clone();
+            // Check to make sure finalZone was actually cloned.
+            if (finalZoneWithStartYear == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+            }
+            finalZone->getID(tzid);
+            firstFinalRule = new TimeArrayTimeZoneRule(tzid,
+                finalZone->getRawOffset(), 0, &startTime, 1, DateTimeRule::UTC_TIME);
+            // Check firstFinalRule was properly created.
+            if (firstFinalRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                deleteTransitionRules();
+                return;
+            }
+        }
+        TimeZoneRule *prevRule = NULL;
+        if (transCount > 0) {
+            prevRule = historicRules[typeMapData[transCount - 1]];
+        }
+        if (prevRule == NULL) {
+            // No historic transitions, but only finalZone available
+            prevRule = initialRule;
+        }
+        firstFinalTZTransition = new TimeZoneTransition();
+        // Check to make sure firstFinalTZTransition was created before dereferencing
+        if (firstFinalTZTransition == NULL) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            deleteTransitionRules();
+            return;
+        }
+        firstFinalTZTransition->setTime(startTime);
+        firstFinalTZTransition->adoptFrom(prevRule->clone());
+        firstFinalTZTransition->adoptTo(firstFinalRule);
+    }
+}
+
+UBool
+OlsonTimeZone::getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const {
+    UErrorCode status = U_ZERO_ERROR;
+    checkTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return FALSE;
+    }
+
+    if (finalZone != NULL) {
+        if (inclusive && base == firstFinalTZTransition->getTime()) {
+            result = *firstFinalTZTransition;
+            return TRUE;
+        } else if (base >= firstFinalTZTransition->getTime()) {
+            if (finalZone->useDaylightTime()) {
+                //return finalZone->getNextTransition(base, inclusive, result);
+                return finalZoneWithStartYear->getNextTransition(base, inclusive, result);
+            } else {
+                // No more transitions
+                return FALSE;
+            }
+        }
+    }
+    if (historicRules != NULL) {
+        // Find a historical transition
+        int16_t transCount = transitionCount();
+        int16_t ttidx = transCount - 1;
+        for (; ttidx >= firstTZTransitionIdx; ttidx--) {
+            UDate t = (UDate)transitionTime(ttidx);
+            if (base > t || (!inclusive && base == t)) {
+                break;
+            }
+        }
+        if (ttidx == transCount - 1)  {
+            if (firstFinalTZTransition != NULL) {
+                result = *firstFinalTZTransition;
+                return TRUE;
+            } else {
+                return FALSE;
+            }
+        } else if (ttidx < firstTZTransitionIdx) {
+            result = *firstTZTransition;
+            return TRUE;
+        } else {
+            // Create a TimeZoneTransition
+            TimeZoneRule *to = historicRules[typeMapData[ttidx + 1]];
+            TimeZoneRule *from = historicRules[typeMapData[ttidx]];
+            UDate startTime = (UDate)transitionTime(ttidx+1);
+
+            // The transitions loaded from zoneinfo.res may contain non-transition data
+            UnicodeString fromName, toName;
+            from->getName(fromName);
+            to->getName(toName);
+            if (fromName == toName && from->getRawOffset() == to->getRawOffset()
+                    && from->getDSTSavings() == to->getDSTSavings()) {
+                return getNextTransition(startTime, false, result);
+            }
+            result.setTime(startTime);
+            result.adoptFrom(from->clone());
+            result.adoptTo(to->clone());
+            return TRUE;
+        }
+    }
+    return FALSE;
+}
+
+UBool
+OlsonTimeZone::getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const {
+    UErrorCode status = U_ZERO_ERROR;
+    checkTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return FALSE;
+    }
+
+    if (finalZone != NULL) {
+        if (inclusive && base == firstFinalTZTransition->getTime()) {
+            result = *firstFinalTZTransition;
+            return TRUE;
+        } else if (base > firstFinalTZTransition->getTime()) {
+            if (finalZone->useDaylightTime()) {
+                //return finalZone->getPreviousTransition(base, inclusive, result);
+                return finalZoneWithStartYear->getPreviousTransition(base, inclusive, result);
+            } else {
+                result = *firstFinalTZTransition;
+                return TRUE;
+            }
+        }
+    }
+
+    if (historicRules != NULL) {
+        // Find a historical transition
+        int16_t ttidx = transitionCount() - 1;
+        for (; ttidx >= firstTZTransitionIdx; ttidx--) {
+            UDate t = (UDate)transitionTime(ttidx);
+            if (base > t || (inclusive && base == t)) {
+                break;
+            }
+        }
+        if (ttidx < firstTZTransitionIdx) {
+            // No more transitions
+            return FALSE;
+        } else if (ttidx == firstTZTransitionIdx) {
+            result = *firstTZTransition;
+            return TRUE;
+        } else {
+            // Create a TimeZoneTransition
+            TimeZoneRule *to = historicRules[typeMapData[ttidx]];
+            TimeZoneRule *from = historicRules[typeMapData[ttidx-1]];
+            UDate startTime = (UDate)transitionTime(ttidx);
+
+            // The transitions loaded from zoneinfo.res may contain non-transition data
+            UnicodeString fromName, toName;
+            from->getName(fromName);
+            to->getName(toName);
+            if (fromName == toName && from->getRawOffset() == to->getRawOffset()
+                    && from->getDSTSavings() == to->getDSTSavings()) {
+                return getPreviousTransition(startTime, false, result);
+            }
+            result.setTime(startTime);
+            result.adoptFrom(from->clone());
+            result.adoptTo(to->clone());
+            return TRUE;
+        }
+    }
+    return FALSE;
+}
+
+int32_t
+OlsonTimeZone::countTransitionRules(UErrorCode& status) const {
+    if (U_FAILURE(status)) {
+        return 0;
+    }
+    checkTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return 0;
+    }
+
+    int32_t count = 0;
+    if (historicRules != NULL) {
+        // historicRules may contain null entries when original zoneinfo data
+        // includes non transition data.
+        for (int32_t i = 0; i < historicRuleCount; i++) {
+            if (historicRules[i] != NULL) {
+                count++;
+            }
+        }
+    }
+    if (finalZone != NULL) {
+        if (finalZone->useDaylightTime()) {
+            count += 2;
+        } else {
+            count++;
+        }
+    }
+    return count;
+}
+
+void
+OlsonTimeZone::getTimeZoneRules(const InitialTimeZoneRule*& initial,
+                                const TimeZoneRule* trsrules[],
+                                int32_t& trscount,
+                                UErrorCode& status) const {
+    if (U_FAILURE(status)) {
+        return;
+    }
+    checkTransitionRules(status);
+    if (U_FAILURE(status)) {
+        return;
+    }
+
+    // Initial rule
+    initial = initialRule;
+
+    // Transition rules
+    int32_t cnt = 0;
+    if (historicRules != NULL && trscount > cnt) {
+        // historicRules may contain null entries when original zoneinfo data
+        // includes non transition data.
+        for (int32_t i = 0; i < historicRuleCount; i++) {
+            if (historicRules[i] != NULL) {
+                trsrules[cnt++] = historicRules[i];
+                if (cnt >= trscount) {
+                    break;
+                }
+            }
+        }
+    }
+    if (finalZoneWithStartYear != NULL && trscount > cnt) {
+        const InitialTimeZoneRule *tmpini;
+        int32_t tmpcnt = trscount - cnt;
+        finalZoneWithStartYear->getTimeZoneRules(tmpini, &trsrules[cnt], tmpcnt, status);
+        if (U_FAILURE(status)) {
+            return;
+        }
+        cnt += tmpcnt;
+    }
+    // Set the result length
+    trscount = cnt;
+}
+
 U_NAMESPACE_END
 
 #endif // !UCONFIG_NO_FORMATTING