ICU-551.51.4.tar.gz

[apple/icu.git] / icuSources / i18n / olsontz.cpp

diff --git a/icuSources/i18n/olsontz.cpp b/icuSources/i18n/olsontz.cpp
index 3fe2861d55f626ef65ebbde525fa1265b0349c45..244876b065b2409d25946ed83023667788fe8eae 100644 (file)
--- a/icuSources/i18n/olsontz.cpp
+++ b/icuSources/i18n/olsontz.cpp
@@ -1,6 +1,6 @@
 /*
 **********************************************************************
-* Copyright (c) 2003-2011, International Business Machines
+* Copyright (c) 2003-2013, International Business Machines
 * Corporation and others.  All Rights Reserved.
 **********************************************************************
 * Author: Alan Liu
@@ -9,7 +9,7 @@
 **********************************************************************
 */
 
-#include <typeinfo>  // for 'typeid' to work
+#include "utypeinfo.h"  // for 'typeid' to work
 
 #include "olsontz.h"
 
@@ -25,6 +25,7 @@
 #include <float.h> // DBL_MAX
 #include "uresimp.h" // struct UResourceBundle
 #include "zonemeta.h"
+#include "umutex.h"
 
 #ifdef U_DEBUG_TZ
 # include <stdio.h>
@@ -118,7 +119,7 @@ OlsonTimeZone::OlsonTimeZone(const UResourceBundle* top,
                              const UResourceBundle* res,
                              const UnicodeString& tzid,
                              UErrorCode& ec) :
-  BasicTimeZone(tzid), finalZone(NULL), transitionRulesInitialized(FALSE)
+  BasicTimeZone(tzid), finalZone(NULL)
 {
     clearTransitionRules();
     U_DEBUG_TZ_MSG(("OlsonTimeZone(%s)\n", ures_getKey((UResourceBundle*)res)));
@@ -399,7 +400,7 @@ void OlsonTimeZone::getOffset(UDate date, UBool local, int32_t& rawoff,
 
 void
 OlsonTimeZone::getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt,
-                                  int32_t& rawoff, int32_t& dstoff, UErrorCode& ec) /*const*/ {
+                                  int32_t& rawoff, int32_t& dstoff, UErrorCode& ec) const {
     if (U_FAILURE(ec)) {
         return;
     }
@@ -463,6 +464,11 @@ OlsonTimeZone::transitionTimeInSeconds(int16_t transIdx) const {
         | ((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,
@@ -487,7 +493,7 @@ OlsonTimeZone::getHistoricalOffset(UDate date, UBool local,
             for (transIdx = transCount - 1; transIdx >= 0; transIdx--) {
                 int64_t transition = transitionTimeInSeconds(transIdx);
 
-                if (local) {
+                if (local && (sec >= (transition - MAX_OFFSET_SECONDS))) {
                     int32_t offsetBefore = zoneOffsetAt(transIdx - 1);
                     UBool dstBefore = dstOffsetAt(transIdx - 1) != 0;
 
@@ -571,7 +577,7 @@ UBool OlsonTimeZone::useDaylightTime() const {
     // Return TRUE if DST is observed at any time during the current
     // year.
     for (int16_t i = 0; i < transitionCount(); ++i) {
-        double transition = transitionTime(i);
+        double transition = (double)transitionTimeInSeconds(i);
         if (transition >= limit) {
             break;
         }
@@ -652,7 +658,7 @@ OlsonTimeZone::clearTransitionRules(void) {
     historicRuleCount = 0;
     finalZoneWithStartYear = NULL;
     firstTZTransitionIdx = 0;
-    transitionRulesInitialized = FALSE;
+    transitionRulesInitOnce.reset();
 }
 
 void
@@ -680,14 +686,25 @@ OlsonTimeZone::deleteTransitionRules(void) {
     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;
     }
-    if (transitionRulesInitialized) {
-        return;
-    }
     deleteTransitionRules();
     UnicodeString tzid;
     getID(tzid);
@@ -856,13 +873,12 @@ OlsonTimeZone::initTransitionRules(UErrorCode& status) {
         firstFinalTZTransition->adoptFrom(prevRule->clone());
         firstFinalTZTransition->adoptTo(firstFinalRule);
     }
-    transitionRulesInitialized = TRUE;
 }
 
 UBool
-OlsonTimeZone::getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) /*const*/ {
+OlsonTimeZone::getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const {
     UErrorCode status = U_ZERO_ERROR;
-    initTransitionRules(status);
+    checkTransitionRules(status);
     if (U_FAILURE(status)) {
         return FALSE;
     }
@@ -925,9 +941,9 @@ OlsonTimeZone::getNextTransition(UDate base, UBool inclusive, TimeZoneTransition
 }
 
 UBool
-OlsonTimeZone::getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) /*const*/ {
+OlsonTimeZone::getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const {
     UErrorCode status = U_ZERO_ERROR;
-    initTransitionRules(status);
+    checkTransitionRules(status);
     if (U_FAILURE(status)) {
         return FALSE;
     }
@@ -986,11 +1002,11 @@ OlsonTimeZone::getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransi
 }
 
 int32_t
-OlsonTimeZone::countTransitionRules(UErrorCode& status) /*const*/ {
+OlsonTimeZone::countTransitionRules(UErrorCode& status) const {
     if (U_FAILURE(status)) {
         return 0;
     }
-    initTransitionRules(status);
+    checkTransitionRules(status);
     if (U_FAILURE(status)) {
         return 0;
     }
@@ -1019,11 +1035,11 @@ void
 OlsonTimeZone::getTimeZoneRules(const InitialTimeZoneRule*& initial,
                                 const TimeZoneRule* trsrules[],
                                 int32_t& trscount,
-                                UErrorCode& status) /*const*/ {
+                                UErrorCode& status) const {
     if (U_FAILURE(status)) {
         return;
     }
-    initTransitionRules(status);
+    checkTransitionRules(status);
     if (U_FAILURE(status)) {
         return;
     }