diff options
Diffstat (limited to 'src/corelib/time/qjuliancalendar.cpp')
| -rw-r--r-- | src/corelib/time/qjuliancalendar.cpp | 73 |
1 files changed, 16 insertions, 57 deletions
diff --git a/src/corelib/time/qjuliancalendar.cpp b/src/corelib/time/qjuliancalendar.cpp index 06ab9bba3d..1439ae3e00 100644 --- a/src/corelib/time/qjuliancalendar.cpp +++ b/src/corelib/time/qjuliancalendar.cpp @@ -1,48 +1,11 @@ -/**************************************************************************** -** -** Copyright (C) 2021 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtCore module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ +// Copyright (C) 2021 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #include "qglobal.h" #include "qjuliancalendar_p.h" #include "qromancalendar_data_p.h" #include "qcalendarmath_p.h" -#include <QtCore/qmath.h> -#include <QtCore/qlocale.h> + #include <QtCore/qdatetime.h> QT_BEGIN_NAMESPACE @@ -90,36 +53,32 @@ bool QJulianCalendar::isLeapYear(int year) const if (year == QCalendar::Unspecified || !year) return false; - return qMod(year < 0 ? year + 1 : year, 4) == 0; + return qMod<4>(year < 0 ? year + 1 : year) == 0; } -// Julian Day 0 was January the first in the proleptic Julian calendar's 4713 BC +// Julian Day 0 was January the first in the proleptic Julian calendar's 4713 BC. +using namespace QRomanCalendrical; +// End a Julian four-year cycle on 1 BC's leap day (Gregorian Feb 27th): +constexpr qint64 JulianBaseJd = LeapDayGregorian1Bce - 2; bool QJulianCalendar::dateToJulianDay(int year, int month, int day, qint64 *jd) const { Q_ASSERT(jd); if (!isDateValid(year, month, day)) return false; - if (year < 0) - ++year; - const qint64 c0 = month < 3 ? -1 : 0; - const qint64 j1 = qDiv(1461 * (year + c0), 4); - const qint64 j2 = qDiv(153 * month - 1836 * c0 - 457, 5); - *jd = j1 + j2 + day + 1721117; + + const auto yearDays = yearMonthToYearDays(year, month); + *jd = qDiv<4>(FourYears * yearDays.year) + yearDays.days + day + JulianBaseJd; return true; } QCalendar::YearMonthDay QJulianCalendar::julianDayToDate(qint64 jd) const { - const qint64 y2 = jd - 1721118; - const qint64 k2 = 4 * y2 + 3; - const qint64 k1 = 5 * qDiv(qMod(k2, 1461), 4) + 2; - const qint64 x1 = qDiv(k1, 153); - const qint64 c0 = qDiv(x1 + 2, 12); - const int y = qint16(qDiv(k2, 1461) + c0); - const int month = quint8(x1 - 12 * c0 + 3); - const int day = qDiv(qMod(k1, 153), 5) + 1; - return QCalendar::YearMonthDay(y > 0 ? y : y - 1, month, day); + const auto year4Day = qDivMod<FourYears>(4 * (jd - JulianBaseJd) - 1); + // Its remainder changes by 4 per day, except at roughly yearly quotient steps. + const auto ymd = dayInYearToYmd(qDiv<4>(year4Day.remainder)); + const int y = year4Day.quotient + ymd.year; + return QCalendar::YearMonthDay(y > 0 ? y : y - 1, ymd.month, ymd.day); } QT_END_NAMESPACE |