ICU-21014 Fix OOM not checked in dtitvfmt.cpp and dtitvinf.cpp

diff --git a/icu4c/source/i18n/dtitvfmt.cpp b/icu4c/source/i18n/dtitvfmt.cpp
index 64b4065292dd5b390bce58efdf1ec3af94002b0f..b71a571d1c490a143573634947a4081da75560d7 100644 (file)
--- a/icu4c/source/i18n/dtitvfmt.cpp
+++ b/icu4c/source/i18n/dtitvfmt.cpp
@@ -108,6 +108,10 @@ DateIntervalFormat::createInstance(const UnicodeString& skeleton,
 #endif
 
     DateIntervalInfo* dtitvinf = new DateIntervalInfo(locale, status);
+    if (dtitvinf == nullptr) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+        return nullptr;
+    }
     return create(locale, dtitvinf, &skeleton, status);
 }
 
@@ -132,27 +136,27 @@ DateIntervalFormat::createInstance(const UnicodeString& skeleton,
 
 
 DateIntervalFormat::DateIntervalFormat()
-:   fInfo(NULL),
-    fDateFormat(NULL),
-    fFromCalendar(NULL),
-    fToCalendar(NULL),
+:   fInfo(nullptr),
+    fDateFormat(nullptr),
+    fFromCalendar(nullptr),
+    fToCalendar(nullptr),
     fLocale(Locale::getRoot()),
-    fDatePattern(NULL),
-    fTimePattern(NULL),
-    fDateTimeFormat(NULL)
+    fDatePattern(nullptr),
+    fTimePattern(nullptr),
+    fDateTimeFormat(nullptr)
 {}
 
 
 DateIntervalFormat::DateIntervalFormat(const DateIntervalFormat& itvfmt)
 :   Format(itvfmt),
-    fInfo(NULL),
-    fDateFormat(NULL),
-    fFromCalendar(NULL),
-    fToCalendar(NULL),
+    fInfo(nullptr),
+    fDateFormat(nullptr),
+    fFromCalendar(nullptr),
+    fToCalendar(nullptr),
     fLocale(itvfmt.fLocale),
-    fDatePattern(NULL),
-    fTimePattern(NULL),
-    fDateTimeFormat(NULL) {
+    fDatePattern(nullptr),
+    fTimePattern(nullptr),
+    fDateTimeFormat(nullptr) {
     *this = itvfmt;
 }
 
@@ -172,23 +176,23 @@ DateIntervalFormat::operator=(const DateIntervalFormat& itvfmt) {
             if ( itvfmt.fDateFormat ) {
                 fDateFormat = itvfmt.fDateFormat->clone();
             } else {
-                fDateFormat = NULL;
+                fDateFormat = nullptr;
             }
             if ( itvfmt.fFromCalendar ) {
                 fFromCalendar = itvfmt.fFromCalendar->clone();
             } else {
-                fFromCalendar = NULL;
+                fFromCalendar = nullptr;
             }
             if ( itvfmt.fToCalendar ) {
                 fToCalendar = itvfmt.fToCalendar->clone();
             } else {
-                fToCalendar = NULL;
+                fToCalendar = nullptr;
             }
         }
         if ( itvfmt.fInfo ) {
             fInfo = itvfmt.fInfo->clone();
         } else {
-            fInfo = NULL;
+            fInfo = nullptr;
         }
         fSkeleton = itvfmt.fSkeleton;
         int8_t i;
@@ -196,9 +200,9 @@ DateIntervalFormat::operator=(const DateIntervalFormat& itvfmt) {
             fIntervalPatterns[i] = itvfmt.fIntervalPatterns[i];
         }
         fLocale = itvfmt.fLocale;
-        fDatePattern    = (itvfmt.fDatePattern)?    itvfmt.fDatePattern->clone(): NULL;
-        fTimePattern    = (itvfmt.fTimePattern)?    itvfmt.fTimePattern->clone(): NULL;
-        fDateTimeFormat = (itvfmt.fDateTimeFormat)? itvfmt.fDateTimeFormat->clone(): NULL;
+        fDatePattern    = (itvfmt.fDatePattern)?    itvfmt.fDatePattern->clone(): nullptr;
+        fTimePattern    = (itvfmt.fTimePattern)?    itvfmt.fTimePattern->clone(): nullptr;
+        fDateTimeFormat = (itvfmt.fDateTimeFormat)? itvfmt.fDateTimeFormat->clone(): nullptr;
     }
     return *this;
 }
@@ -227,21 +231,21 @@ DateIntervalFormat::operator==(const Format& other) const {
     const DateIntervalFormat* fmt = (DateIntervalFormat*)&other;
     if (this == fmt) {return TRUE;}
     if (!Format::operator==(other)) {return FALSE;}
-    if ((fInfo != fmt->fInfo) && (fInfo == NULL || fmt->fInfo == NULL)) {return FALSE;}
+    if ((fInfo != fmt->fInfo) && (fInfo == nullptr || fmt->fInfo == nullptr)) {return FALSE;}
     if (fInfo && fmt->fInfo && (*fInfo != *fmt->fInfo )) {return FALSE;}
     {
         Mutex lock(&gFormatterMutex);
-        if (fDateFormat != fmt->fDateFormat && (fDateFormat == NULL || fmt->fDateFormat == NULL)) {return FALSE;}
+        if (fDateFormat != fmt->fDateFormat && (fDateFormat == nullptr || fmt->fDateFormat == nullptr)) {return FALSE;}
         if (fDateFormat && fmt->fDateFormat && (*fDateFormat != *fmt->fDateFormat)) {return FALSE;}
     }
     // note: fFromCalendar and fToCalendar hold no persistent state, and therefore do not participate in operator ==.
     //       fDateFormat has the master calendar for the DateIntervalFormat.
     if (fSkeleton != fmt->fSkeleton) {return FALSE;}
-    if (fDatePattern != fmt->fDatePattern && (fDatePattern == NULL || fmt->fDatePattern == NULL)) {return FALSE;}
+    if (fDatePattern != fmt->fDatePattern && (fDatePattern == nullptr || fmt->fDatePattern == nullptr)) {return FALSE;}
     if (fDatePattern && fmt->fDatePattern && (*fDatePattern != *fmt->fDatePattern)) {return FALSE;}
-    if (fTimePattern != fmt->fTimePattern && (fTimePattern == NULL || fmt->fTimePattern == NULL)) {return FALSE;}
+    if (fTimePattern != fmt->fTimePattern && (fTimePattern == nullptr || fmt->fTimePattern == nullptr)) {return FALSE;}
     if (fTimePattern && fmt->fTimePattern && (*fTimePattern != *fmt->fTimePattern)) {return FALSE;}
-    if (fDateTimeFormat != fmt->fDateTimeFormat && (fDateTimeFormat == NULL || fmt->fDateTimeFormat == NULL)) {return FALSE;}
+    if (fDateTimeFormat != fmt->fDateTimeFormat && (fDateTimeFormat == nullptr || fmt->fDateTimeFormat == nullptr)) {return FALSE;}
     if (fDateTimeFormat && fmt->fDateTimeFormat && (*fDateTimeFormat != *fmt->fDateTimeFormat)) {return FALSE;}
     if (fLocale != fmt->fLocale) {return FALSE;}
 
@@ -266,7 +270,7 @@ DateIntervalFormat::format(const Formattable& obj,
     if ( obj.getType() == Formattable::kObject ) {
         const UObject* formatObj = obj.getObject();
         const DateInterval* interval = dynamic_cast<const DateInterval*>(formatObj);
-        if (interval != NULL) {
+        if (interval != nullptr) {
             return format(interval, appendTo, fieldPosition, status);
         }
     }
@@ -283,7 +287,7 @@ DateIntervalFormat::format(const DateInterval* dtInterval,
     if ( U_FAILURE(status) ) {
         return appendTo;
     }
-    if (fDateFormat == NULL || fInfo == NULL) {
+    if (fDateFormat == nullptr || fInfo == nullptr) {
         status = U_INVALID_STATE_ERROR;
         return appendTo;
     }
@@ -300,6 +304,10 @@ DateIntervalFormat::format(const DateInterval* dtInterval,
 FormattedDateInterval DateIntervalFormat::formatToValue(
         const DateInterval& dtInterval,
         UErrorCode& status) const {
+    if (U_FAILURE(status)) {
+        return FormattedDateInterval(status);
+    }
+    // LocalPointer only sets OOM status if U_SUCCESS is true.
     LocalPointer<FormattedDateIntervalData> result(new FormattedDateIntervalData(status), status);
     if (U_FAILURE(status)) {
         return FormattedDateInterval(status);
@@ -350,6 +358,10 @@ FormattedDateInterval DateIntervalFormat::formatToValue(
         Calendar& fromCalendar,
         Calendar& toCalendar,
         UErrorCode& status) const {
+    if (U_FAILURE(status)) {
+        return FormattedDateInterval(status);
+    }
+    // LocalPointer only sets OOM status if U_SUCCESS is true.
     LocalPointer<FormattedDateIntervalData> result(new FormattedDateIntervalData(status), status);
     if (U_FAILURE(status)) {
         return FormattedDateInterval(status);
@@ -540,14 +552,17 @@ DateIntervalFormat::setDateIntervalInfo(const DateIntervalInfo& newItvPattern,
                                         UErrorCode& status) {
     delete fInfo;
     fInfo = new DateIntervalInfo(newItvPattern);
+    if (fInfo == nullptr) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+    }
 
     // Delete patterns that get reset by initializePattern
     delete fDatePattern;
-    fDatePattern = NULL;
+    fDatePattern = nullptr;
     delete fTimePattern;
-    fTimePattern = NULL;
+    fTimePattern = nullptr;
     delete fDateTimeFormat;
-    fDateTimeFormat = NULL;
+    fDateTimeFormat = nullptr;
 
     if (fDateFormat) {
         initializePattern(status);
@@ -565,7 +580,7 @@ DateIntervalFormat::getDateFormat() const {
 void
 DateIntervalFormat::adoptTimeZone(TimeZone* zone)
 {
-    if (fDateFormat != NULL) {
+    if (fDateFormat != nullptr) {
         fDateFormat->adoptTimeZone(zone);
     }
     // The fDateFormat has the master calendar for the DateIntervalFormat and has
@@ -583,7 +598,7 @@ DateIntervalFormat::adoptTimeZone(TimeZone* zone)
 void
 DateIntervalFormat::setTimeZone(const TimeZone& zone)
 {
-    if (fDateFormat != NULL) {
+    if (fDateFormat != nullptr) {
         fDateFormat->setTimeZone(zone);
     }
     // The fDateFormat has the master calendar for the DateIntervalFormat;
@@ -599,11 +614,11 @@ DateIntervalFormat::setTimeZone(const TimeZone& zone)
 const TimeZone&
 DateIntervalFormat::getTimeZone() const
 {
-    if (fDateFormat != NULL) {
+    if (fDateFormat != nullptr) {
         Mutex lock(&gFormatterMutex);
         return fDateFormat->getTimeZone();
     }
-    // If fDateFormat is NULL (unexpected), create default timezone.
+    // If fDateFormat is nullptr (unexpected), create default timezone.
     return *(TimeZone::createDefault());
 }
 
@@ -611,14 +626,14 @@ DateIntervalFormat::DateIntervalFormat(const Locale& locale,
                                        DateIntervalInfo* dtItvInfo,
                                        const UnicodeString* skeleton,
                                        UErrorCode& status)
-:   fInfo(NULL),
-    fDateFormat(NULL),
-    fFromCalendar(NULL),
-    fToCalendar(NULL),
+:   fInfo(nullptr),
+    fDateFormat(nullptr),
+    fFromCalendar(nullptr),
+    fToCalendar(nullptr),
     fLocale(locale),
-    fDatePattern(NULL),
-    fTimePattern(NULL),
-    fDateTimeFormat(NULL)
+    fDatePattern(nullptr),
+    fTimePattern(nullptr),
+    fDateTimeFormat(nullptr)
 {
     LocalPointer<DateIntervalInfo> info(dtItvInfo, status);
     LocalPointer<SimpleDateFormat> dtfmt(static_cast<SimpleDateFormat *>(
@@ -646,7 +661,7 @@ DateIntervalFormat::create(const Locale& locale,
                            UErrorCode& status) {
     DateIntervalFormat* f = new DateIntervalFormat(locale, dtitvinf,
                                                    skeleton, status);
-    if ( f == NULL ) {
+    if ( f == nullptr ) {
         status = U_MEMORY_ALLOCATION_ERROR;
         delete dtitvinf;
     } else if ( U_FAILURE(status) ) {
@@ -763,7 +778,7 @@ DateIntervalFormat::initializePattern(UErrorCode& status) {
         // with the time interval.
         // The date/time pattern ( such as {0} {1} ) is saved in
         // calendar, that is why need to get the CalendarData here.
-        LocalUResourceBundlePointer dateTimePatternsRes(ures_open(NULL, locale.getBaseName(), &status));
+        LocalUResourceBundlePointer dateTimePatternsRes(ures_open(nullptr, locale.getBaseName(), &status));
         ures_getByKey(dateTimePatternsRes.getAlias(), gCalendarTag,
                       dateTimePatternsRes.getAlias(), &status);
         ures_getByKeyWithFallback(dateTimePatternsRes.getAlias(), gGregorianTag,
@@ -778,6 +793,10 @@ DateIntervalFormat::initializePattern(UErrorCode& status) {
                                             &dateTimeFormatLength, &status);
         if ( U_SUCCESS(status) && dateTimeFormatLength >= 3 ) {
             fDateTimeFormat = new UnicodeString(dateTimeFormat, dateTimeFormatLength);
+            if (fDateTimeFormat == nullptr) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                return;
+            }
         }
     }
 
@@ -801,9 +820,9 @@ DateIntervalFormat::initializePattern(UErrorCode& status) {
                 // the first part of the pattern is empty,
                 // the second part of the pattern is the full-pattern
                 // should be used in fall-back.
-                setPatternInfo(UCAL_DATE, NULL, &pattern, fInfo->getDefaultOrder());
-                setPatternInfo(UCAL_MONTH, NULL, &pattern, fInfo->getDefaultOrder());
-                setPatternInfo(UCAL_YEAR, NULL, &pattern, fInfo->getDefaultOrder());
+                setPatternInfo(UCAL_DATE, nullptr, &pattern, fInfo->getDefaultOrder());
+                setPatternInfo(UCAL_MONTH, nullptr, &pattern, fInfo->getDefaultOrder());
+                setPatternInfo(UCAL_YEAR, nullptr, &pattern, fInfo->getDefaultOrder());
             } else {
                 // TODO: fall back
             }
@@ -827,9 +846,9 @@ DateIntervalFormat::initializePattern(UErrorCode& status) {
         // the first part of the pattern is empty,
         // the second part of the pattern is the full-pattern
         // should be used in fall-back.
-        setPatternInfo(UCAL_DATE, NULL, &pattern, fInfo->getDefaultOrder());
-        setPatternInfo(UCAL_MONTH, NULL, &pattern, fInfo->getDefaultOrder());
-        setPatternInfo(UCAL_YEAR, NULL, &pattern, fInfo->getDefaultOrder());
+        setPatternInfo(UCAL_DATE, nullptr, &pattern, fInfo->getDefaultOrder());
+        setPatternInfo(UCAL_MONTH, nullptr, &pattern, fInfo->getDefaultOrder());
+        setPatternInfo(UCAL_YEAR, nullptr, &pattern, fInfo->getDefaultOrder());
     } else {
         /* if both present,
          * 1) when the year, month, or day differs,
@@ -864,7 +883,7 @@ DateIntervalFormat::initializePattern(UErrorCode& status) {
          * range expression for the time.
          */
 
-        if ( fDateTimeFormat == NULL ) {
+        if ( fDateTimeFormat == nullptr ) {
             // earlier failure getting dateTimeFormat
             return;
         }
@@ -1074,16 +1093,16 @@ DateIntervalFormat::setSeparateDateTimePtn(
     int8_t differenceInfo = 0;
     const UnicodeString* bestSkeleton = fInfo->getBestSkeleton(*skeleton,
                                                                differenceInfo);
-    /* best skeleton could be NULL.
+    /* best skeleton could be nullptr.
        For example: in "ca" resource file,
        interval format is defined as following
            intervalFormats{
                 fallback{"{0} - {1}"}
             }
        there is no skeletons/interval patterns defined,
-       and the best skeleton match could be NULL
+       and the best skeleton match could be nullptr
      */
-    if ( bestSkeleton == NULL ) {
+    if ( bestSkeleton == nullptr ) {
         return false;
     }
 
@@ -1094,11 +1113,13 @@ DateIntervalFormat::setSeparateDateTimePtn(
         status = U_ZERO_ERROR;
         fDatePattern = new UnicodeString(DateFormat::getBestPattern(
                 fLocale, dateSkeleton, status));
+        // no way to report OOM. :(
     }
     if ( timeSkeleton.length() != 0) {
         status = U_ZERO_ERROR;
         fTimePattern = new UnicodeString(DateFormat::getBestPattern(
                 fLocale, timeSkeleton, status));
+        // no way to report OOM. :(
     }
 
     // difference:
@@ -1154,7 +1175,7 @@ DateIntervalFormat::setFallbackPattern(UCalendarDateFields field,
     if ( U_FAILURE(status) ) {
         return;
     }
-    setPatternInfo(field, NULL, &pattern, fInfo->getDefaultOrder());
+    setPatternInfo(field, nullptr, &pattern, fInfo->getDefaultOrder());
 }
 
 

diff --git a/icu4c/source/i18n/dtitvinf.cpp b/icu4c/source/i18n/dtitvinf.cpp
index b263765c06678b4761f7e6312905d8444b630071..25536346ec74f03e3185c937cc7d52641dd04f44 100644 (file)
--- a/icu4c/source/i18n/dtitvinf.cpp
+++ b/icu4c/source/i18n/dtitvinf.cpp
@@ -66,7 +66,7 @@ static const UChar gDefaultFallbackPattern[] = {LEFT_CURLY_BRACKET, DIGIT_ZERO,
 DateIntervalInfo::DateIntervalInfo(UErrorCode& status)
 :   fFallbackIntervalPattern(gDefaultFallbackPattern),
     fFirstDateInPtnIsLaterDate(false),
-    fIntervalPatterns(NULL)
+    fIntervalPatterns(nullptr)
 {
     fIntervalPatterns = initHash(status);
 }
@@ -76,7 +76,7 @@ DateIntervalInfo::DateIntervalInfo(UErrorCode& status)
 DateIntervalInfo::DateIntervalInfo(const Locale& locale, UErrorCode& status)
 :   fFallbackIntervalPattern(gDefaultFallbackPattern),
     fFirstDateInPtnIsLaterDate(false),
-    fIntervalPatterns(NULL)
+    fIntervalPatterns(nullptr)
 {
     initializeData(locale, status);
 }
@@ -126,7 +126,7 @@ DateIntervalInfo::setFallbackIntervalPattern(
 
 DateIntervalInfo::DateIntervalInfo(const DateIntervalInfo& dtitvinf)
 :   UObject(dtitvinf),
-    fIntervalPatterns(NULL)
+    fIntervalPatterns(nullptr)
 {
     *this = dtitvinf;
 }
@@ -161,7 +161,7 @@ DateIntervalInfo::clone() const {
 
 DateIntervalInfo::~DateIntervalInfo() {
     deleteHash(fIntervalPatterns);
-    fIntervalPatterns = NULL;
+    fIntervalPatterns = nullptr;
 }
 
 
@@ -189,7 +189,7 @@ DateIntervalInfo::getIntervalPattern(const UnicodeString& skeleton,
     }
 
     const UnicodeString* patternsOfOneSkeleton = (UnicodeString*) fIntervalPatterns->get(skeleton);
-    if ( patternsOfOneSkeleton != NULL ) {
+    if ( patternsOfOneSkeleton != nullptr ) {
         IntervalPatternIndex index = calendarFieldToIntervalIndex(field, status);
         if ( U_FAILURE(status) ) {
             return result;
@@ -363,7 +363,7 @@ struct DateIntervalInfo::DateIntervalSink : public ResourceSink {
         UnicodeString* patternsOfOneSkeleton =
             (UnicodeString*)(dateIntervalInfo.fIntervalPatterns->get(skeleton));
 
-        if (patternsOfOneSkeleton == NULL || patternsOfOneSkeleton[index].isEmpty()) {
+        if (patternsOfOneSkeleton == nullptr || patternsOfOneSkeleton[index].isEmpty()) {
             UnicodeString pattern = value.getUnicodeString(errorCode);
             dateIntervalInfo.setIntervalPatternInternally(skeleton, lrgDiffCalUnit,
                                                           pattern, errorCode);
@@ -398,8 +398,8 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& status)
     char         calendarType[ULOC_KEYWORDS_CAPACITY]; // to be filled in with the type to use, if all goes well
     char         localeWithCalendarKey[ULOC_LOCALE_IDENTIFIER_CAPACITY];
     // obtain a locale that always has the calendar key value that should be used
-    (void)ures_getFunctionalEquivalent(localeWithCalendarKey, ULOC_LOCALE_IDENTIFIER_CAPACITY, NULL,
-                                     "calendar", "calendar", locName, NULL, FALSE, &status);
+    (void)ures_getFunctionalEquivalent(localeWithCalendarKey, ULOC_LOCALE_IDENTIFIER_CAPACITY, nullptr,
+                                     "calendar", "calendar", locName, nullptr, FALSE, &status);
     localeWithCalendarKey[ULOC_LOCALE_IDENTIFIER_CAPACITY-1] = 0; // ensure null termination
     // now get the calendar key value from that locale
     int32_t calendarTypeLen = uloc_getKeywordValue(localeWithCalendarKey, "calendar", calendarType,
@@ -411,11 +411,11 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& status)
 
     // Instantiate the resource bundles
     UResourceBundle *rb, *calBundle;
-    rb = ures_open(NULL, locName, &status);
+    rb = ures_open(nullptr, locName, &status);
     if (U_FAILURE(status)) {
         return;
     }
-    calBundle = ures_getByKeyWithFallback(rb, gCalendarTag, NULL, &status);
+    calBundle = ures_getByKeyWithFallback(rb, gCalendarTag, nullptr, &status);
 
 
     if (U_SUCCESS(status)) {
@@ -424,9 +424,9 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& status)
         // Get the fallback pattern
         const UChar* resStr = nullptr;
         int32_t resStrLen = 0;
-        calTypeBundle = ures_getByKeyWithFallback(calBundle, calendarTypeToUse, NULL, &status);
+        calTypeBundle = ures_getByKeyWithFallback(calBundle, calendarTypeToUse, nullptr, &status);
         itvDtPtnResource = ures_getByKeyWithFallback(calTypeBundle,
-                                                     gIntervalDateTimePatternTag, NULL, &status);
+                                                     gIntervalDateTimePatternTag, nullptr, &status);
         // TODO(ICU-20400): After the fixing, we should find the "fallback" from
         // the rb directly by the path "calendar/${calendar}/intervalFormats/fallback".
         if ( U_SUCCESS(status) ) {
@@ -437,10 +437,10 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& status)
                 // ures_getByKeyWithFallback
                 UErrorCode localStatus = U_ZERO_ERROR;
                 UResourceBundle *genericCalBundle =
-                    ures_getByKeyWithFallback(calBundle, gGenericTag, NULL, &localStatus);
+                    ures_getByKeyWithFallback(calBundle, gGenericTag, nullptr, &localStatus);
                 UResourceBundle *genericItvDtPtnResource =
                     ures_getByKeyWithFallback(
-                        genericCalBundle, gIntervalDateTimePatternTag, NULL, &localStatus);
+                        genericCalBundle, gIntervalDateTimePatternTag, nullptr, &localStatus);
                 resStr = ures_getStringByKeyWithFallback(
                     genericItvDtPtnResource, gFallbackPatternTag, &resStrLen, &localStatus);
                 ures_close(genericItvDtPtnResource);
@@ -509,8 +509,12 @@ DateIntervalInfo::setIntervalPatternInternally(const UnicodeString& skeleton,
     }
     UnicodeString* patternsOfOneSkeleton = (UnicodeString*)(fIntervalPatterns->get(skeleton));
     UBool emptyHash = false;
-    if ( patternsOfOneSkeleton == NULL ) {
+    if ( patternsOfOneSkeleton == nullptr ) {
         patternsOfOneSkeleton = new UnicodeString[kIPI_MAX_INDEX];
+        if (patternsOfOneSkeleton == nullptr) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            return;
+        }
         emptyHash = true;
     }
 
@@ -608,7 +612,7 @@ DateIntervalInfo::getBestSkeleton(const UnicodeString& skeleton,
 
     parseSkeleton(*inputSkeleton, inputSkeletonFieldWidth);
     int32_t bestDistance = MAX_POSITIVE_INT;
-    const UnicodeString* bestSkeleton = NULL;
+    const UnicodeString* bestSkeleton = nullptr;
 
     // 0 means exact the same skeletons;
     // 1 means having the same field, but with different length,
@@ -618,8 +622,8 @@ DateIntervalInfo::getBestSkeleton(const UnicodeString& skeleton,
     int8_t fieldLength = UPRV_LENGTHOF(skeletonFieldWidth);
 
     int32_t pos = UHASH_FIRST;
-    const UHashElement* elem = NULL;
-    while ( (elem = fIntervalPatterns->nextElement(pos)) != NULL ) {
+    const UHashElement* elem = nullptr;
+    while ( (elem = fIntervalPatterns->nextElement(pos)) != nullptr ) {
         const UHashTok keyTok = elem->key;
         UnicodeString* newSkeleton = (UnicodeString*)keyTok.pointer;
 #ifdef DTITVINF_DEBUG
@@ -725,12 +729,12 @@ DateIntervalInfo::calendarFieldToIntervalIndex(UCalendarDateFields field,
 void
 DateIntervalInfo::deleteHash(Hashtable* hTable)
 {
-    if ( hTable == NULL ) {
+    if ( hTable == nullptr ) {
         return;
     }
     int32_t pos = UHASH_FIRST;
-    const UHashElement* element = NULL;
-    while ( (element = hTable->nextElement(pos)) != NULL ) {
+    const UHashElement* element = nullptr;
+    while ( (element = hTable->nextElement(pos)) != nullptr ) {
         const UHashTok valueTok = element->value;
         const UnicodeString* value = (UnicodeString*)valueTok.pointer;
         delete[] value;
@@ -768,16 +772,16 @@ U_CDECL_END
 Hashtable*
 DateIntervalInfo::initHash(UErrorCode& status) {
     if ( U_FAILURE(status) ) {
-        return NULL;
+        return nullptr;
     }
     Hashtable* hTable;
-    if ( (hTable = new Hashtable(FALSE, status)) == NULL ) {
+    if ( (hTable = new Hashtable(FALSE, status)) == nullptr ) {
         status = U_MEMORY_ALLOCATION_ERROR;
-        return NULL;
+        return nullptr;
     }
     if ( U_FAILURE(status) ) {
         delete hTable;
-        return NULL;
+        return nullptr;
     }
     hTable->setValueComparator(dtitvinfHashTableValueComparator);
     return hTable;
@@ -792,14 +796,18 @@ DateIntervalInfo::copyHash(const Hashtable* source,
         return;
     }
     int32_t pos = UHASH_FIRST;
-    const UHashElement* element = NULL;
+    const UHashElement* element = nullptr;
     if ( source ) {
-        while ( (element = source->nextElement(pos)) != NULL ) {
+        while ( (element = source->nextElement(pos)) != nullptr ) {
             const UHashTok keyTok = element->key;
             const UnicodeString* key = (UnicodeString*)keyTok.pointer;
             const UHashTok valueTok = element->value;
             const UnicodeString* value = (UnicodeString*)valueTok.pointer;
             UnicodeString* copy = new UnicodeString[kIPI_MAX_INDEX];
+            if (copy == nullptr) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                return;
+            }
             int8_t i;
             for ( i = 0; i < kIPI_MAX_INDEX; ++i ) {
                 copy[i] = value[i];