diff options
Diffstat (limited to 'src/corelib/tools/qdatetime.cpp')
| -rw-r--r-- | src/corelib/tools/qdatetime.cpp | 324 |
1 files changed, 290 insertions, 34 deletions
diff --git a/src/corelib/tools/qdatetime.cpp b/src/corelib/tools/qdatetime.cpp index 969065ffee..0f8c8629a8 100644 --- a/src/corelib/tools/qdatetime.cpp +++ b/src/corelib/tools/qdatetime.cpp @@ -1,6 +1,6 @@ /**************************************************************************** ** -** Copyright (C) 2017 The Qt Company Ltd. +** Copyright (C) 2019 The Qt Company Ltd. ** Copyright (C) 2016 Intel Corporation. ** Contact: https://www.qt.io/licensing/ ** @@ -58,6 +58,9 @@ #endif #include <cmath> +#ifdef Q_CC_MINGW +# include <unistd.h> // Define _POSIX_THREAD_SAFE_FUNCTIONS to obtain localtime_r() +#endif #include <time.h> #ifdef Q_OS_WIN # include <qt_windows.h> @@ -169,12 +172,11 @@ static ParsedDate getDateFromJulianDay(qint64 julianDay) Date/Time formatting helper functions *****************************************************************************/ -static const char monthDays[] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; - #if QT_CONFIG(textdate) static const char qt_shortMonthNames[][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", - "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; + "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" +}; static int qt_monthNumberFromShortName(QStringRef shortName) { @@ -301,6 +303,12 @@ static int fromOffsetString(const QStringRef &offsetString, bool *valid) noexcep } #endif // datestring +static constexpr int daysInUsualMonth(int month) // (February isn't usual.) +{ + // Long if odd up to July = 7, or if even from 8 = August onwards: + return Q_ASSERT(month != 2 && month > 0 && month <= 12), 30 | ((month & 1) ^ (month >> 3)); +} + /***************************************************************************** QDate member functions *****************************************************************************/ @@ -419,7 +427,6 @@ QDate::QDate(int y, int m, int d) \sa isValid() */ - /*! \fn bool QDate::isValid() const @@ -428,7 +435,6 @@ QDate::QDate(int y, int m, int d) \sa isNull() */ - /*! Returns the year of this date. Negative numbers indicate years before 1 CE, such that year -44 is 44 BCE. @@ -544,10 +550,10 @@ int QDate::daysInMonth() const return 0; const ParsedDate pd = getDateFromJulianDay(jd); - if (pd.month == 2 && isLeapYear(pd.year)) - return 29; - else - return monthDays[pd.month]; + if (pd.month == 2) + return isLeapYear(pd.year) ? 29 : 28; + + return daysInUsualMonth(pd.month); } /*! @@ -614,7 +620,270 @@ int QDate::weekNumber(int *yearNumber) const return week; } +static bool inDateTimeRange(qint64 jd, bool start) +{ + using Bounds = std::numeric_limits<qint64>; + if (jd < Bounds::min() + JULIAN_DAY_FOR_EPOCH) + return false; + jd -= JULIAN_DAY_FOR_EPOCH; + const qint64 maxDay = Bounds::max() / MSECS_PER_DAY; + const qint64 minDay = Bounds::min() / MSECS_PER_DAY - 1; + // (Divisions rounded towards zero, as MSECS_PER_DAY has factors other than two.) + // Range includes start of last day and end of first: + if (start) + return jd > minDay && jd <= maxDay; + return jd >= minDay && jd < maxDay; +} + +static QDateTime toEarliest(const QDate &day, const QDateTime &form) +{ + const Qt::TimeSpec spec = form.timeSpec(); + const int offset = (spec == Qt::OffsetFromUTC) ? form.offsetFromUtc() : 0; +#if QT_CONFIG(timezone) + QTimeZone zone; + if (spec == Qt::TimeZone) + zone = form.timeZone(); +#endif + auto moment = [=](QTime time) { + switch (spec) { + case Qt::OffsetFromUTC: return QDateTime(day, time, spec, offset); +#if QT_CONFIG(timezone) + case Qt::TimeZone: return QDateTime(day, time, zone); +#endif + default: return QDateTime(day, time, spec); + } + }; + // Longest routine time-zone transition is 2 hours: + QDateTime when = moment(QTime(2, 0)); + if (!when.isValid()) { + // Noon should be safe ... + when = moment(QTime(12, 0)); + if (!when.isValid()) { + // ... unless it's a 24-hour jump (moving the date-line) + when = moment(QTime(23, 59, 59, 999)); + if (!when.isValid()) + return QDateTime(); + } + } + int high = when.time().msecsSinceStartOfDay() / 60000; + int low = 0; + // Binary chop to the right minute + while (high > low + 1) { + int mid = (high + low) / 2; + QDateTime probe = moment(QTime(mid / 60, mid % 60)); + if (probe.isValid() && probe.date() == day) { + high = mid; + when = probe; + } else { + low = mid; + } + } + return when; +} + +/*! + \since 5.14 + \fn QDateTime QDate::startOfDay(Qt::TimeSpec spec, int offsetSeconds) const + \fn QDateTime QDate::startOfDay(const QTimeZone &zone) const + + Returns the start-moment of the day. Usually, this shall be midnight at the + start of the day: however, if a time-zone transition causes the given date + to skip over that midnight (e.g. a DST spring-forward skipping from the end + of the previous day to 01:00 of the new day), the actual earliest time in + the day is returned. This can only arise when the start-moment is specified + in terms of a time-zone (by passing its QTimeZone as \a zone) or in terms of + local time (by passing Qt::LocalTime as \a spec; this is its default). + + The \a offsetSeconds is ignored unless \a spec is Qt::OffsetFromUTC, when it + gives the implied zone's offset from UTC. As UTC and such zones have no + transitions, the start of the day is QTime(0, 0) in these cases. + + In the rare case of a date that was entirely skipped (this happens when a + zone east of the international date-line switches to being west of it), the + return shall be invalid. Passing Qt::TimeZone as \a spec (instead of + passing a QTimeZone) or passing an invalid time-zone as \a zone will also + produce an invalid result, as shall dates that start outside the range + representable by QDateTime. + + \sa endOfDay() +*/ +QDateTime QDate::startOfDay(Qt::TimeSpec spec, int offsetSeconds) const +{ + if (!inDateTimeRange(jd, true)) + return QDateTime(); + + switch (spec) { + case Qt::TimeZone: // should pass a QTimeZone instead of Qt::TimeZone + qWarning() << "Called QDate::startOfDay(Qt::TimeZone) on" << *this; + return QDateTime(); + case Qt::OffsetFromUTC: + case Qt::UTC: + return QDateTime(*this, QTime(0, 0), spec, offsetSeconds); + + case Qt::LocalTime: + if (offsetSeconds) + qWarning("Ignoring offset (%d seconds) passed with Qt::LocalTime", offsetSeconds); + break; + } + QDateTime when(*this, QTime(0, 0), spec); + if (!when.isValid()) + when = toEarliest(*this, when); + + return when.isValid() ? when : QDateTime(); +} + +#if QT_CONFIG(timezone) +/*! + \overload + \since 5.14 +*/ +QDateTime QDate::startOfDay(const QTimeZone &zone) const +{ + if (!inDateTimeRange(jd, true) || !zone.isValid()) + return QDateTime(); + + QDateTime when(*this, QTime(0, 0), zone); + if (when.isValid()) + return when; + + // The start of the day must have fallen in a spring-forward's gap; find the spring-forward: + if (zone.hasTransitions()) { + QTimeZone::OffsetData tran = zone.previousTransition(QDateTime(*this, QTime(23, 59, 59, 999), zone)); + const QDateTime &at = tran.atUtc.toTimeZone(zone); + if (at.isValid() && at.date() == *this) + return at; + } + + when = toEarliest(*this, when); + return when.isValid() ? when : QDateTime(); +} +#endif // timezone + +static QDateTime toLatest(const QDate &day, const QDateTime &form) +{ + const Qt::TimeSpec spec = form.timeSpec(); + const int offset = (spec == Qt::OffsetFromUTC) ? form.offsetFromUtc() : 0; +#if QT_CONFIG(timezone) + QTimeZone zone; + if (spec == Qt::TimeZone) + zone = form.timeZone(); +#endif + auto moment = [=](QTime time) { + switch (spec) { + case Qt::OffsetFromUTC: return QDateTime(day, time, spec, offset); +#if QT_CONFIG(timezone) + case Qt::TimeZone: return QDateTime(day, time, zone); +#endif + default: return QDateTime(day, time, spec); + } + }; + // Longest routine time-zone transition is 2 hours: + QDateTime when = moment(QTime(21, 59, 59, 999)); + if (!when.isValid()) { + // Noon should be safe ... + when = moment(QTime(12, 0)); + if (!when.isValid()) { + // ... unless it's a 24-hour jump (moving the date-line) + when = moment(QTime(0, 0)); + if (!when.isValid()) + return QDateTime(); + } + } + int high = 24 * 60; + int low = when.time().msecsSinceStartOfDay() / 60000; + // Binary chop to the right minute + while (high > low + 1) { + int mid = (high + low) / 2; + QDateTime probe = moment(QTime(mid / 60, mid % 60, 59, 999)); + if (probe.isValid() && probe.date() == day) { + low = mid; + when = probe; + } else { + high = mid; + } + } + return when; +} + +/*! + \since 5.14 + \fn QDateTime QDate::endOfDay(Qt::TimeSpec spec, int offsetSeconds) const + \fn QDateTime QDate::endOfDay(const QTimeZone &zone) const + + Returns the end-moment of the day. Usually, this is one millisecond before + the midnight at the end of the day: however, if a time-zone transition + causes the given date to skip over that midnight (e.g. a DST spring-forward + skipping from just before 23:00 to the start of the next day), the actual + latest time in the day is returned. This can only arise when the + start-moment is specified in terms of a time-zone (by passing its QTimeZone + as \a zone) or in terms of local time (by passing Qt::LocalTime as \a spec; + this is its default). + + The \a offsetSeconds is ignored unless \a spec is Qt::OffsetFromUTC, when it + gives the implied zone's offset from UTC. As UTC and such zones have no + transitions, the end of the day is QTime(23, 59, 59, 999) in these cases. + + In the rare case of a date that was entirely skipped (this happens when a + zone east of the international date-line switches to being west of it), the + return shall be invalid. Passing Qt::TimeZone as \a spec (instead of + passing a QTimeZone) will also produce an invalid result, as shall dates + that end outside the range representable by QDateTime. + + \sa startOfDay() +*/ +QDateTime QDate::endOfDay(Qt::TimeSpec spec, int offsetSeconds) const +{ + if (!inDateTimeRange(jd, false)) + return QDateTime(); + + switch (spec) { + case Qt::TimeZone: // should pass a QTimeZone instead of Qt::TimeZone + qWarning() << "Called QDate::endOfDay(Qt::TimeZone) on" << *this; + return QDateTime(); + case Qt::UTC: + case Qt::OffsetFromUTC: + return QDateTime(*this, QTime(23, 59, 59, 999), spec, offsetSeconds); + + case Qt::LocalTime: + if (offsetSeconds) + qWarning("Ignoring offset (%d seconds) passed with Qt::LocalTime", offsetSeconds); + break; + } + QDateTime when(*this, QTime(23, 59, 59, 999), spec); + if (!when.isValid()) + when = toLatest(*this, when); + return when.isValid() ? when : QDateTime(); +} + +#if QT_CONFIG(timezone) +/*! + \overload + \since 5.14 +*/ +QDateTime QDate::endOfDay(const QTimeZone &zone) const +{ + if (!inDateTimeRange(jd, false) || !zone.isValid()) + return QDateTime(); + + QDateTime when(*this, QTime(23, 59, 59, 999), zone); + if (when.isValid()) + return when; + + // The end of the day must have fallen in a spring-forward's gap; find the spring-forward: + if (zone.hasTransitions()) { + QTimeZone::OffsetData tran = zone.nextTransition(QDateTime(*this, QTime(0, 0), zone)); + const QDateTime &at = tran.atUtc.toTimeZone(zone); + if (at.isValid() && at.date() == *this) + return at; + } + + when = toLatest(*this, when); + return when.isValid() ? when : QDateTime(); +} +#endif // timezone + #if QT_DEPRECATED_SINCE(5, 11) && QT_CONFIG(textdate) + /*! \since 4.5 \deprecated @@ -1210,8 +1479,6 @@ qint64 QDate::daysTo(const QDate &d) const #if QT_CONFIG(datestring) /*! - \fn QDate QDate::fromString(const QString &string, Qt::DateFormat format) - Returns the QDate represented by the \a string, using the \a format given, or an invalid date if the string cannot be parsed. @@ -1222,7 +1489,8 @@ qint64 QDate::daysTo(const QDate &d) const \sa toString(), QLocale::toDate() */ -QDate QDate::fromString(const QString& string, Qt::DateFormat format) + +QDate QDate::fromString(const QString &string, Qt::DateFormat format) { if (string.isEmpty()) return QDate(); @@ -1279,8 +1547,6 @@ QDate QDate::fromString(const QString& string, Qt::DateFormat format) } /*! - \fn QDate QDate::fromString(const QString &string, const QString &format) - Returns the QDate represented by the \a string, using the \a format given, or an invalid date if the string cannot be parsed. @@ -1373,12 +1639,9 @@ QDate QDate::fromString(const QString &string, const QString &format) bool QDate::isValid(int year, int month, int day) { - // there is no year 0 in the Gregorian calendar - if (year == 0) - return false; - - return (day > 0 && month > 0 && month <= 12) && - (day <= monthDays[month] || (day == 29 && month == 2 && isLeapYear(year))); + // There is no year 0 in the Gregorian calendar. + return year && day > 0 && month > 0 && month <= 12 && + day <= (month == 2 ? isLeapYear(year) ? 29 : 28 : daysInUsualMonth(month)); } /*! @@ -1465,7 +1728,8 @@ bool QDate::isLeapYear(int y) \fn QTime::QTime() Constructs a null time object. For a null time, isNull() returns \c true and - isValid() returns \c false. If you need a zero time, use QTime(0, 0). + isValid() returns \c false. If you need a zero time, use QTime(0, 0). For + the start of a day, see QDate::startOfDay(). \sa isNull(), isValid() */ @@ -1973,8 +2237,6 @@ static QTime fromIsoTimeString(const QStringRef &string, Qt::DateFormat format, } /*! - \fn QTime QTime::fromString(const QString &string, Qt::DateFormat format) - Returns the time represented in the \a string as a QTime using the \a format given, or an invalid time if this is not possible. @@ -1986,7 +2248,7 @@ static QTime fromIsoTimeString(const QStringRef &string, Qt::DateFormat format, \sa toString(), QLocale::toTime() */ -QTime QTime::fromString(const QString& string, Qt::DateFormat format) +QTime QTime::fromString(const QString &string, Qt::DateFormat format) { if (string.isEmpty()) return QTime(); @@ -2013,8 +2275,6 @@ QTime QTime::fromString(const QString& string, Qt::DateFormat format) } /*! - \fn QTime QTime::fromString(const QString &string, const QString &format) - Returns the QTime represented by the \a string, using the \a format given, or an invalid time if the string cannot be parsed. @@ -2389,8 +2649,8 @@ static void msecsToTime(qint64 msecs, QDate *date, QTime *time) qint64 jd = JULIAN_DAY_FOR_EPOCH; qint64 ds = 0; - if (qAbs(msecs) >= MSECS_PER_DAY) { - jd += (msecs / MSECS_PER_DAY); + if (msecs >= MSECS_PER_DAY || msecs <= -MSECS_PER_DAY) { + jd += msecs / MSECS_PER_DAY; msecs %= MSECS_PER_DAY; } @@ -4734,8 +4994,6 @@ int QDateTime::utcOffset() const #if QT_CONFIG(datestring) /*! - \fn QDateTime QDateTime::fromString(const QString &string, Qt::DateFormat format) - Returns the QDateTime represented by the \a string, using the \a format given, or an invalid datetime if this is not possible. @@ -4745,7 +5003,7 @@ int QDateTime::utcOffset() const \sa toString(), QLocale::toDateTime() */ -QDateTime QDateTime::fromString(const QString& string, Qt::DateFormat format) +QDateTime QDateTime::fromString(const QString &string, Qt::DateFormat format) { if (string.isEmpty()) return QDateTime(); @@ -4952,8 +5210,6 @@ QDateTime QDateTime::fromString(const QString& string, Qt::DateFormat format) } /*! - \fn QDateTime QDateTime::fromString(const QString &string, const QString &format) - Returns the QDateTime represented by the \a string, using the \a format given, or an invalid datetime if the string cannot be parsed. |