From 03fadc26e7617aece89949bc7d0acf50f6f050a9 Mon Sep 17 00:00:00 2001 From: Edward Welbourne Date: Thu, 21 Mar 2019 15:07:48 +0100 Subject: [PATCH] Fix broken data for time-zones with no transitions While an invalid time-zone shall have no transitions, so may various constant zones, like UTC. The TZ data may include only the POSIX rule for such a zone, in which case we should use it, even if there are no transitions. Broke out a piece of repeated code as a common method, in the process, since I was complicating it further. Added test for the case that revealed this; and made sure we see a warning if any of the checkOffset() tests gets skipped because its zone is unsupported. Fixes: QTBUG-74614 Change-Id: Ic8e039a2a9b3f4e0f567585682a94f4b494b558d Reviewed-by: Thiago Macieira --- src/corelib/tools/qtimezoneprivate_p.h | 1 + src/corelib/tools/qtimezoneprivate_tz.cpp | 46 +++++++++---------- .../corelib/tools/qtimezone/tst_qtimezone.cpp | 4 ++ 3 files changed, 27 insertions(+), 24 deletions(-) diff --git a/src/corelib/tools/qtimezoneprivate_p.h b/src/corelib/tools/qtimezoneprivate_p.h index c9a57262166..24a9a00f112 100644 --- a/src/corelib/tools/qtimezoneprivate_p.h +++ b/src/corelib/tools/qtimezoneprivate_p.h @@ -331,6 +331,7 @@ public: private: void init(const QByteArray &ianaId); + QVector getPosixTransitions(qint64 msNear) const; Data dataForTzTransition(QTzTransitionTime tran) const; QVector m_tranTimes; diff --git a/src/corelib/tools/qtimezoneprivate_tz.cpp b/src/corelib/tools/qtimezoneprivate_tz.cpp index fa4ec031fae..f75a61977db 100644 --- a/src/corelib/tools/qtimezoneprivate_tz.cpp +++ b/src/corelib/tools/qtimezoneprivate_tz.cpp @@ -943,19 +943,21 @@ QTimeZonePrivate::Data QTzTimeZonePrivate::dataForTzTransition(QTzTransitionTime return data; } +QVector QTzTimeZonePrivate::getPosixTransitions(qint64 msNear) const +{ + const int year = QDateTime::fromMSecsSinceEpoch(msNear, Qt::UTC).date().year(); + // The Data::atMSecsSinceEpoch of the single entry if zone is constant: + qint64 atTime = m_tranTimes.isEmpty() ? msNear : m_tranTimes.last().atMSecsSinceEpoch; + return calculatePosixTransitions(m_posixRule, year - 1, year + 1, atTime); +} + QTimeZonePrivate::Data QTzTimeZonePrivate::data(qint64 forMSecsSinceEpoch) const { - // If we have no rules (so probably an invalid tz), return invalid data: - if (!m_tranTimes.size()) - return invalidData(); - - // If the required time is after the last transition and we have a POSIX rule then use it - if (m_tranTimes.last().atMSecsSinceEpoch < forMSecsSinceEpoch + // If the required time is after the last transition (or there were none) + // and we have a POSIX rule then use it: + if ((m_tranTimes.isEmpty() || m_tranTimes.last().atMSecsSinceEpoch < forMSecsSinceEpoch) && !m_posixRule.isEmpty() && forMSecsSinceEpoch >= 0) { - const int year = QDateTime::fromMSecsSinceEpoch(forMSecsSinceEpoch, Qt::UTC).date().year(); - QVector posixTrans = - calculatePosixTransitions(m_posixRule, year - 1, year + 1, - m_tranTimes.last().atMSecsSinceEpoch); + QVector posixTrans = getPosixTransitions(forMSecsSinceEpoch); auto it = std::partition_point(posixTrans.cbegin(), posixTrans.cend(), [forMSecsSinceEpoch] (const QTimeZonePrivate::Data &at) { return at.atMSecsSinceEpoch <= forMSecsSinceEpoch; @@ -986,13 +988,11 @@ bool QTzTimeZonePrivate::hasTransitions() const QTimeZonePrivate::Data QTzTimeZonePrivate::nextTransition(qint64 afterMSecsSinceEpoch) const { - // If the required time is after the last transition and we have a POSIX rule then use it - if (m_tranTimes.size() > 0 && m_tranTimes.last().atMSecsSinceEpoch < afterMSecsSinceEpoch + // If the required time is after the last transition (or there were none) + // and we have a POSIX rule then use it: + if ((m_tranTimes.isEmpty() || m_tranTimes.last().atMSecsSinceEpoch < afterMSecsSinceEpoch) && !m_posixRule.isEmpty() && afterMSecsSinceEpoch >= 0) { - const int year = QDateTime::fromMSecsSinceEpoch(afterMSecsSinceEpoch, Qt::UTC).date().year(); - QVector posixTrans = - calculatePosixTransitions(m_posixRule, year - 1, year + 1, - m_tranTimes.last().atMSecsSinceEpoch); + QVector posixTrans = getPosixTransitions(afterMSecsSinceEpoch); auto it = std::partition_point(posixTrans.cbegin(), posixTrans.cend(), [afterMSecsSinceEpoch] (const QTimeZonePrivate::Data &at) { return at.atMSecsSinceEpoch <= afterMSecsSinceEpoch; @@ -1011,21 +1011,19 @@ QTimeZonePrivate::Data QTzTimeZonePrivate::nextTransition(qint64 afterMSecsSince QTimeZonePrivate::Data QTzTimeZonePrivate::previousTransition(qint64 beforeMSecsSinceEpoch) const { - // If the required time is after the last transition and we have a POSIX rule then use it - if (m_tranTimes.size() > 0 && m_tranTimes.last().atMSecsSinceEpoch < beforeMSecsSinceEpoch + // If the required time is after the last transition (or there were none) + // and we have a POSIX rule then use it: + if ((m_tranTimes.isEmpty() || m_tranTimes.last().atMSecsSinceEpoch < beforeMSecsSinceEpoch) && !m_posixRule.isEmpty() && beforeMSecsSinceEpoch > 0) { - const int year = QDateTime::fromMSecsSinceEpoch(beforeMSecsSinceEpoch, Qt::UTC).date().year(); - QVector posixTrans = - calculatePosixTransitions(m_posixRule, year - 1, year + 1, - m_tranTimes.last().atMSecsSinceEpoch); + QVector posixTrans = getPosixTransitions(beforeMSecsSinceEpoch); auto it = std::partition_point(posixTrans.cbegin(), posixTrans.cend(), [beforeMSecsSinceEpoch] (const QTimeZonePrivate::Data &at) { return at.atMSecsSinceEpoch < beforeMSecsSinceEpoch; }); if (it > posixTrans.cbegin()) return *--it; - // else: it fell between the last transition and the first of the POSIX rule. - return dataForTzTransition(m_tranTimes.last()); + // It fell between the last transition (if any) and the first of the POSIX rule: + return m_tranTimes.isEmpty() ? invalidData() : dataForTzTransition(m_tranTimes.last()); } // Otherwise if we can find a valid tran then use its rule diff --git a/tests/auto/corelib/tools/qtimezone/tst_qtimezone.cpp b/tests/auto/corelib/tools/qtimezone/tst_qtimezone.cpp index a25fd39693b..eff98357769 100644 --- a/tests/auto/corelib/tools/qtimezone/tst_qtimezone.cpp +++ b/tests/auto/corelib/tools/qtimezone/tst_qtimezone.cpp @@ -539,6 +539,8 @@ void tst_QTimeZone::checkOffset_data() int year, month, day, hour, min, sec; int std, dst; } table[] = { + // Zone with no transitions (QTBUG-74614, when TZ backend uses minimalist data) + { "Etc/UTC", "epoch", 1970, 1, 1, 0, 0, 0, 0, 0 }, // Kiev: regression test for QTBUG-64122 (on MS): { "Europe/Kiev", "summer", 2017, 10, 27, 12, 0, 0, 2 * 3600, 3600 }, { "Europe/Kiev", "winter", 2017, 10, 29, 12, 0, 0, 2 * 3600, 0 } @@ -551,6 +553,8 @@ void tst_QTimeZone::checkOffset_data() << QDateTime(QDate(entry.year, entry.month, entry.day), QTime(entry.hour, entry.min, entry.sec), zone) << entry.dst + entry.std << entry.std << entry.dst; + } else { + qWarning("Skipping %s@%s test as zone is invalid", entry.zone, entry.nick); } } }