Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 1586 insertions, 0 deletions

diff --git a/tools/source/datetime/datetime.cxx b/tools/source/datetime/datetime.cxx
new file mode 100644
index 000000000..00790ff78
--- /dev/null
+++ b/tools/source/datetime/datetime.cxx
@@ -0,0 +1,306 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#include <tools/datetime.hxx>
+#include <rtl/math.hxx>
+#include <sal/log.hxx>
+
+#include <systemdatetime.hxx>
+
+DateTime::DateTime(DateTimeInitSystem)
+    : Date( Date::EMPTY )
+    , Time( Time::EMPTY )
+{
+    sal_Int32 nD = 0;
+    sal_Int64 nT = 0;
+    if ( GetSystemDateTime( &nD, &nT ) )
+    {
+        Date::operator=( Date( nD ) );
+        SetTime( nT );
+    }
+    else
+        Date::operator=( Date( 1, 1, 1900 ) ); // Time::nTime is already 0
+}
+
+DateTime::DateTime( const css::util::DateTime& rDateTime )
+  : Date( rDateTime.Day, rDateTime.Month, rDateTime.Year ),
+    Time( rDateTime.Hours, rDateTime.Minutes, rDateTime.Seconds, rDateTime.NanoSeconds )
+{
+}
+
+DateTime& DateTime::operator =( const css::util::DateTime& rUDateTime )
+{
+    Date::operator=( Date( rUDateTime.Day, rUDateTime.Month, rUDateTime.Year));
+    Time::operator=( Time( rUDateTime));
+    return *this;
+}
+
+bool DateTime::IsBetween( const DateTime& rFrom, const DateTime& rTo ) const
+{
+    return (*this >= rFrom) && (*this <= rTo);
+}
+
+bool DateTime::operator >( const DateTime& rDateTime ) const
+{
+    return (Date::operator>( rDateTime )) ||
+         (Date::operator==( rDateTime ) && tools::Time::operator>( rDateTime ));
+}
+
+bool DateTime::operator <( const DateTime& rDateTime ) const
+{
+    return (Date::operator<( rDateTime )) ||
+         (Date::operator==( rDateTime ) && tools::Time::operator<( rDateTime ));
+}
+
+bool DateTime::operator >=( const DateTime& rDateTime ) const
+{
+    return (Date::operator>( rDateTime )) ||
+         (Date::operator==( rDateTime ) && tools::Time::operator>=( rDateTime ));
+}
+
+bool DateTime::operator <=( const DateTime& rDateTime ) const
+{
+    return (Date::operator<( rDateTime )) ||
+         (Date::operator==( rDateTime ) && tools::Time::operator<=( rDateTime ));
+}
+
+sal_Int64 DateTime::GetSecFromDateTime( const Date& rDate ) const
+{
+    if ( Date::operator<( rDate ) )
+        return 0;
+    else
+    {
+        sal_Int64 nSec = Date( *this ) - rDate;
+        nSec *= 24UL*60*60;
+        sal_Int64 nHour = GetHour();
+        sal_Int64 nMin  = GetMin();
+        nSec += (nHour*3600)+(nMin*60)+GetSec();
+        return nSec;
+    }
+}
+
+DateTime& DateTime::operator +=( const tools::Time& rTime )
+{
+    tools::Time aTime = *this;
+    aTime += rTime;
+    sal_uInt16 nHours = aTime.GetHour();
+    if ( aTime.GetTime() > 0 )
+    {
+        while ( nHours >= 24 )
+        {
+            Date::operator++();
+            nHours -= 24;
+        }
+        aTime.SetHour( nHours );
+    }
+    else if ( aTime.GetTime() != 0 )
+    {
+        while ( nHours >= 24 )
+        {
+            Date::operator--();
+            nHours -= 24;
+        }
+        Date::operator--();
+        aTime = Time( 24, 0, 0 )+aTime;
+    }
+    tools::Time::operator=( aTime );
+
+    return *this;
+}
+
+DateTime& DateTime::operator -=( const tools::Time& rTime )
+{
+    tools::Time aTime = *this;
+    aTime -= rTime;
+    sal_uInt16 nHours = aTime.GetHour();
+    if ( aTime.GetTime() > 0 )
+    {
+        while ( nHours >= 24 )
+        {
+            Date::operator++();
+            nHours -= 24;
+        }
+        aTime.SetHour( nHours );
+    }
+    else if ( aTime.GetTime() != 0 )
+    {
+        while ( nHours >= 24 )
+        {
+            Date::operator--();
+            nHours -= 24;
+        }
+        Date::operator--();
+        aTime = Time( 24, 0, 0 )+aTime;
+    }
+    tools::Time::operator=( aTime );
+
+    return *this;
+}
+
+DateTime operator +( const DateTime& rDateTime, sal_Int32 nDays )
+{
+    DateTime aDateTime( rDateTime );
+    aDateTime.AddDays( nDays );
+    return aDateTime;
+}
+
+DateTime operator -( const DateTime& rDateTime, sal_Int32 nDays )
+{
+    DateTime aDateTime( rDateTime );
+    aDateTime.AddDays( -nDays );
+    return aDateTime;
+}
+
+DateTime operator +( const DateTime& rDateTime, const tools::Time& rTime )
+{
+    DateTime aDateTime( rDateTime );
+    aDateTime += rTime;
+    return aDateTime;
+}
+
+DateTime operator -( const DateTime& rDateTime, const tools::Time& rTime )
+{
+    DateTime aDateTime( rDateTime );
+    aDateTime -= rTime;
+    return aDateTime;
+}
+
+void DateTime::AddTime( double fTimeInDays )
+{
+    double fInt, fFrac;
+    if ( fTimeInDays < 0.0 )
+    {
+        fInt = ::rtl::math::approxCeil( fTimeInDays );
+        fFrac = fInt <= fTimeInDays ? 0.0 : fTimeInDays - fInt;
+    }
+    else
+    {
+        fInt = ::rtl::math::approxFloor( fTimeInDays );
+        fFrac = fInt >= fTimeInDays ? 0.0 : fTimeInDays - fInt;
+    }
+    AddDays( sal_Int32(fInt) );     // full days
+    if ( fFrac )
+    {
+        tools::Time aTime(0);  // default ctor calls system time, we don't need that
+        fFrac *= ::tools::Time::nanoSecPerDay;   // time expressed in nanoseconds
+        aTime.MakeTimeFromNS( static_cast<sal_Int64>(fFrac) );    // method handles negative ns
+        operator+=( aTime );
+    }
+}
+
+DateTime operator +( const DateTime& rDateTime, double fTimeInDays )
+{
+    DateTime aDateTime( rDateTime );
+    aDateTime.AddTime( fTimeInDays );
+    return aDateTime;
+}
+
+double operator -( const DateTime& rDateTime1, const DateTime& rDateTime2 )
+{
+    sal_Int32 nDays = static_cast<const Date&>(rDateTime1)
+        - static_cast<const Date&>(rDateTime2);
+    sal_Int64 nTime = rDateTime1.GetNSFromTime() - rDateTime2.GetNSFromTime();
+    if ( nTime )
+    {
+        double fTime = double(nTime);
+        fTime /= ::tools::Time::nanoSecPerDay; // convert from nanoseconds to fraction
+        if ( nDays < 0 && fTime > 0.0 )
+            fTime = 1.0 - fTime;
+        return double(nDays) + fTime;
+    }
+    return double(nDays);
+}
+
+void DateTime::GetWin32FileDateTime( sal_uInt32 & rLower, sal_uInt32 & rUpper ) const
+{
+    const sal_Int64 a100nPerSecond = SAL_CONST_INT64( 10000000 );
+    const sal_Int64 a100nPerDay = a100nPerSecond * sal_Int64( 60 * 60 * 24 );
+
+    // FILETIME is indirectly documented as uint64, see
+    // https://msdn.microsoft.com/en-us/library/windows/desktop/ms724284.aspx
+    // mentioning the ULARGE_INTEGER structure.
+    // https://msdn.microsoft.com/en-us/library/windows/desktop/ms724280.aspx
+    // mentions that if FILETIME is not less than 0x8000000000000000 then the
+    // FileTimeToSystemTime function fails, which is another indicator.
+    // Unless there's evidence that FILETIME can represent a signed offset from
+    // 1601-01-01 truncate at 0. (reading part below in
+    // CreateFromWin32FileDateTime() would had to be adapted to signed as
+    // well).
+    sal_Int16 nYear = GetYear();
+    SAL_WARN_IF( nYear < 1601, "tools.datetime", "DateTime::GetWin32FileDateTime - year < 1601: " << nYear);
+
+    sal_Int64 aTime = (nYear < 1601 ? 0 : (
+        a100nPerDay * (*this - Date(1,1,1601)) +
+        GetNSFromTime()/100));
+
+    rLower = sal_uInt32( aTime % SAL_CONST_UINT64( 0x100000000 ) );
+    rUpper = sal_uInt32( aTime / SAL_CONST_UINT64( 0x100000000 ) );
+}
+
+DateTime DateTime::CreateFromWin32FileDateTime( sal_uInt32 rLower, sal_uInt32 rUpper )
+{
+    // (rUpper|rLower) = 100-nanosecond intervals since 1601-01-01 00:00
+    const sal_uInt64 a100nPerSecond = SAL_CONST_UINT64( 10000000 );
+    const sal_uInt64 a100nPerDay = a100nPerSecond * sal_uInt64( 60 * 60 * 24 );
+
+    sal_uInt64 aTime =
+            sal_uInt64( rUpper ) * SAL_CONST_UINT64( 0x100000000 ) +
+            sal_uInt64( rLower );
+
+    SAL_WARN_IF( static_cast<sal_Int64>(aTime) < 0, "tools.datetime",
+            "DateTime::CreateFromWin32FileDateTime - absurdly high value expected?");
+
+    sal_uInt64 nDays = aTime / a100nPerDay;
+
+    Date aDate(1,1,1601);
+    // (0xffffffffffffffff / a100nPerDay = 21350398) fits into sal_Int32
+    // (0x7fffffff = 2147483647)
+    aDate.AddDays(nDays);
+
+    SAL_WARN_IF( aDate - Date(1,1,1601) != static_cast<sal_Int32>(nDays), "tools.datetime",
+            "DateTime::CreateFromWin32FileDateTime - date truncated to max");
+
+    sal_uInt64 nNanos = (aTime - (nDays * a100nPerDay)) * 100;
+    return DateTime( aDate, tools::Time(
+                static_cast<sal_uInt32>((nNanos / tools::Time::nanoSecPerHour)   % sal_uInt64( 24 )),
+                static_cast<sal_uInt32>((nNanos / tools::Time::nanoSecPerMinute) % sal_uInt64( 60 )),
+                static_cast<sal_uInt32>((nNanos / tools::Time::nanoSecPerSec)    % sal_uInt64( 60 )),
+                static_cast<sal_uInt64>( nNanos % tools::Time::nanoSecPerSec)));
+}
+
+DateTime DateTime::CreateFromUnixTime(const double fSecondsSinceEpoch)
+{
+    double fValue = fSecondsSinceEpoch / Time::secondPerDay;
+    const sal_Int32 nDays = static_cast <sal_Int32>(::rtl::math::approxFloor(fValue));
+
+    Date aDate (1, 1, 1970);
+    aDate.AddDays(nDays);
+    SAL_WARN_IF(aDate - Date(1, 1, 1970) != nDays, "tools.datetime",
+                "DateTime::CreateFromUnixTime - date truncated to max");
+
+    fValue -= nDays;
+
+    const sal_uInt64 nNanos = fValue * tools::Time::nanoSecPerDay;
+    return DateTime( aDate, tools::Time(
+                static_cast<sal_uInt32>((nNanos / tools::Time::nanoSecPerHour)   % sal_uInt64( 24 )),
+                static_cast<sal_uInt32>((nNanos / tools::Time::nanoSecPerMinute) % sal_uInt64( 60 )),
+                static_cast<sal_uInt32>((nNanos / tools::Time::nanoSecPerSec)    % sal_uInt64( 60 )),
+                static_cast<sal_uInt64>( nNanos % tools::Time::nanoSecPerSec)));
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/tools/source/datetime/datetimeutils.cxx b/tools/source/datetime/datetimeutils.cxx
new file mode 100644
index 000000000..4c3b28d49
--- /dev/null
+++ b/tools/source/datetime/datetimeutils.cxx
@@ -0,0 +1,82 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include <tools/datetimeutils.hxx>
+#include <rtl/strbuf.hxx>
+
+
+/// Append the number as 2-digit when less than 10.
+static void lcl_AppendTwoDigits( OStringBuffer &rBuffer, sal_Int32 nNum )
+{
+    if ( nNum < 0 || nNum > 99 )
+    {
+        rBuffer.append( "00" );
+        return;
+    }
+
+    if ( nNum < 10 )
+        rBuffer.append( '0' );
+
+    rBuffer.append( nNum );
+}
+
+OString DateTimeToOString( const DateTime& rDateTime )
+{
+    const DateTime& aInUTC( rDateTime );
+// HACK: this is correct according to the spec, but MSOffice believes everybody lives
+// in UTC+0 when reading it back
+//    aInUTC.ConvertToUTC();
+
+    OStringBuffer aBuffer( 25 );
+    aBuffer.append( sal_Int32( aInUTC.GetYear() ) );
+    aBuffer.append( '-' );
+
+    lcl_AppendTwoDigits( aBuffer, aInUTC.GetMonth() );
+    aBuffer.append( '-' );
+
+    lcl_AppendTwoDigits( aBuffer, aInUTC.GetDay() );
+    aBuffer.append( 'T' );
+
+    lcl_AppendTwoDigits( aBuffer, aInUTC.GetHour() );
+    aBuffer.append( ':' );
+
+    lcl_AppendTwoDigits( aBuffer, aInUTC.GetMin() );
+    aBuffer.append( ':' );
+
+    lcl_AppendTwoDigits( aBuffer, aInUTC.GetSec() );
+    aBuffer.append( 'Z' ); // we are in UTC
+
+    return aBuffer.makeStringAndClear();
+}
+
+OString DateToOString( const Date& rDate )
+{
+    tools::Time aTime( tools::Time::EMPTY );
+    return DateTimeToOString( DateTime( rDate, aTime ) );
+}
+
+OString DateToDDMMYYYYOString( const Date& rDate )
+{
+    OStringBuffer aBuffer( 25 );
+    lcl_AppendTwoDigits( aBuffer, rDate.GetDay() );
+    aBuffer.append( '/' );
+
+    lcl_AppendTwoDigits( aBuffer, rDate.GetMonth() );
+    aBuffer.append( '/' );
+
+    aBuffer.append( sal_Int32( rDate.GetYear() ) );
+
+    return aBuffer.makeStringAndClear();
+}
+
+std::ostream& operator<<(std::ostream& os, const Date& rDate)
+{
+    os << rDate.GetYear() << "-" << rDate.GetMonth() << "-" << rDate.GetDay();
+    return os;
+}
diff --git a/tools/source/datetime/systemdatetime.cxx b/tools/source/datetime/systemdatetime.cxx
new file mode 100644
index 000000000..2115f4b62
--- /dev/null
+++ b/tools/source/datetime/systemdatetime.cxx
@@ -0,0 +1,107 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#if defined(_WIN32)
+#if !defined WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+#include <windows.h>
+#elif defined UNX
+#include <sys/time.h>
+#endif
+
+#include <time.h>
+#ifdef __MACH__
+#include <mach/clock.h>
+#include <mach/mach.h>
+#include <mach/mach_time.h>
+#endif
+
+#include <osl/diagnose.h>
+#include <systemdatetime.hxx>
+
+namespace
+{
+constexpr sal_Int32 ConvertYMDToInt(sal_Int32 nYear, sal_Int32 nMonth, sal_Int32 nDay)
+{
+    return (nYear * 10000) + (nMonth * 100) + nDay;
+}
+
+constexpr sal_Int64 ConvertHMSnToInt(sal_Int64 nHour, sal_Int64 nMin, sal_Int64 nSec,
+                                     sal_Int64 nNanoSec)
+{
+    return (nHour * HOUR_MASK) + (nMin * MIN_MASK) + (nSec * SEC_MASK) + nNanoSec;
+}
+}
+
+bool GetSystemDateTime(sal_Int32* pDate, sal_Int64* pTime)
+{
+#if defined(_WIN32)
+    SYSTEMTIME aDateTime;
+    GetLocalTime(&aDateTime);
+
+    if (pDate)
+        *pDate = ConvertYMDToInt(static_cast<sal_Int32>(aDateTime.wYear),
+                                 static_cast<sal_Int32>(aDateTime.wMonth),
+                                 static_cast<sal_Int32>(aDateTime.wDay));
+    if (pTime)
+        *pTime = ConvertHMSnToInt(aDateTime.wHour, aDateTime.wMinute, aDateTime.wSecond,
+                                  aDateTime.wMilliseconds * 1000000);
+
+    return true;
+#else
+    struct timespec tsTime;
+#if defined(__MACH__)
+    // macOS does not have clock_gettime, use clock_get_time
+    clock_serv_t cclock;
+    mach_timespec_t mts;
+    host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
+    clock_get_time(cclock, &mts);
+    mach_port_deallocate(mach_task_self(), cclock);
+    tsTime.tv_sec = mts.tv_sec;
+    tsTime.tv_nsec = mts.tv_nsec;
+#else
+    // CLOCK_REALTIME should be supported
+    // on any modern Unix, but be extra cautious
+    if (clock_gettime(CLOCK_REALTIME, &tsTime) != 0)
+    {
+        struct timeval tvTime;
+        OSL_VERIFY(gettimeofday(&tvTime, nullptr) != 0);
+        tsTime.tv_sec = tvTime.tv_sec;
+        tsTime.tv_nsec = tvTime.tv_usec * 1000;
+    }
+#endif
+
+    struct tm aTime;
+    time_t nTmpTime = tsTime.tv_sec;
+    if (localtime_r(&nTmpTime, &aTime))
+    {
+        if (pDate)
+            *pDate = ConvertYMDToInt(static_cast<sal_Int32>(aTime.tm_year + 1900),
+                                     static_cast<sal_Int32>(aTime.tm_mon + 1),
+                                     static_cast<sal_Int32>(aTime.tm_mday));
+        if (pTime)
+            *pTime = ConvertHMSnToInt(aTime.tm_hour, aTime.tm_min, aTime.tm_sec, tsTime.tv_nsec);
+        return true;
+    }
+
+    return false;
+#endif
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/tools/source/datetime/tdate.cxx b/tools/source/datetime/tdate.cxx
new file mode 100644
index 000000000..979611333
--- /dev/null
+++ b/tools/source/datetime/tdate.cxx
@@ -0,0 +1,597 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#include <tools/date.hxx>
+#include <sal/log.hxx>
+#include <com/sun/star/util/DateTime.hpp>
+
+#include <systemdatetime.hxx>
+
+const sal_uInt16 aDaysInMonth[12] = { 31, 28, 31, 30, 31, 30,
+                                             31, 31, 30, 31, 30, 31 };
+
+// Once upon a time the number of days we internally handled was limited to
+// MAX_DAYS 3636532. That changed with a full 16-bit year.
+// Assuming the first valid positive date in a proleptic Gregorian calendar is
+// 0001-01-01, this resulted in an end date of 9957-06-26.
+// Hence we documented that years up to and including 9956 are handled.
+/* XXX: it is unclear history why this value was chosen, the representable
+ * 9999-12-31 would be 3652060 days from 0001-01-01. Even 9998-12-31 to
+ * distinguish from a maximum possible date would be 3651695.
+ * There is connectivity/source/commontools/dbconversion.cxx that still has the
+ * same value to calculate with css::util::Date */
+/* XXX can that dbconversion cope with years > 9999 or negative years at all?
+ * Database fields may be limited to positive 4 digits. */
+
+const sal_Int32 MIN_DAYS = -11968265;     // -32768-01-01
+const sal_Int32 MAX_DAYS =  11967900;     //  32767-12-31
+
+namespace
+{
+
+const sal_Int16 kYearMax = SAL_MAX_INT16;
+const sal_Int16 kYearMin = SAL_MIN_INT16;
+
+// Days until start of year from zero, so month and day of month can be added.
+// year 1 => 0 days, year 2 => 365 days, ...
+// year -1 => -366 days, year -2 => -731 days, ...
+sal_Int32 ImpYearToDays( sal_Int16 nYear )
+{
+    assert( nYear != 0 );
+    sal_Int32 nOffset;
+    sal_Int32 nYr;
+    if (nYear < 0)
+    {
+        nOffset = -366;
+        nYr = nYear + 1;
+    }
+    else
+    {
+        nOffset = 0;
+        nYr = nYear - 1;
+    }
+    return nOffset + nYr*365 + nYr/4 - nYr/100 + nYr/400;
+}
+
+bool ImpIsLeapYear( sal_Int16 nYear )
+{
+    // Leap years BCE are -1, -5, -9, ...
+    // See
+    // https://en.wikipedia.org/wiki/Proleptic_Gregorian_calendar#Usage
+    // https://en.wikipedia.org/wiki/0_(year)#History_of_astronomical_usage
+    assert( nYear != 0 );
+    if (nYear < 0)
+        nYear = -nYear - 1;
+    return ( ( ((nYear % 4) == 0) && ((nYear % 100) != 0) ) ||
+             ( (nYear % 400) == 0 ) );
+}
+
+// All callers must have sanitized or normalized month and year values!
+sal_uInt16 ImplDaysInMonth( sal_uInt16 nMonth, sal_Int16 nYear )
+{
+    if ( nMonth != 2 )
+        return aDaysInMonth[nMonth-1];
+    else
+    {
+        if (ImpIsLeapYear(nYear))
+            return aDaysInMonth[nMonth-1] + 1;
+        else
+            return aDaysInMonth[nMonth-1];
+    }
+}
+
+}
+
+void Date::setDateFromDMY( sal_uInt16 nDay, sal_uInt16 nMonth, sal_Int16 nYear )
+{
+    // don't warn about 0/0/0, commonly used as a default-value/no-value
+    SAL_WARN_IF( nYear == 0 && !(nYear == 0 && nMonth == 0 && nDay == 0),
+        "tools.datetime", "Date::setDateFromDMY - sure about 0 year? It's not in the calendar.");
+    assert( nMonth < 100 && "nMonth % 100 not representable" );
+    assert(   nDay < 100 && "nDay % 100 not representable" );
+    if (nYear < 0)
+        mnDate =
+            (static_cast<sal_Int32>( nYear        ) * 10000) -
+            (static_cast<sal_Int32>( nMonth % 100 ) * 100) -
+             static_cast<sal_Int32>( nDay   % 100 );
+    else
+        mnDate =
+            (static_cast<sal_Int32>( nYear        ) * 10000) +
+            (static_cast<sal_Int32>( nMonth % 100 ) * 100) +
+             static_cast<sal_Int32>( nDay   % 100 );
+}
+
+void Date::SetDate( sal_Int32 nNewDate )
+{
+    assert( ((nNewDate / 10000) != 0) && "you don't want to set a 0 year, do you?" );
+    mnDate = nNewDate;
+}
+
+// static
+sal_uInt16 Date::GetDaysInMonth( sal_uInt16 nMonth, sal_Int16 nYear )
+{
+    SAL_WARN_IF( nMonth < 1 || 12 < nMonth, "tools.datetime", "Date::GetDaysInMonth - nMonth out of bounds " << nMonth);
+    if (nMonth < 1)
+        nMonth = 1;
+    else if (12 < nMonth)
+        nMonth = 12;
+    return ImplDaysInMonth( nMonth, nYear);
+}
+
+sal_Int32 Date::GetAsNormalizedDays() const
+{
+    // This is a very common datum we often calculate from.
+    if (mnDate == 18991230) // 1899-12-30
+    {
+        assert(DateToDays( GetDay(), GetMonth(), GetYear() ) == 693594);
+        return 693594;
+    }
+    return DateToDays( GetDay(), GetMonth(), GetYear() );
+}
+
+sal_Int32 Date::DateToDays( sal_uInt16 nDay, sal_uInt16 nMonth, sal_Int16 nYear )
+{
+    Normalize( nDay, nMonth, nYear);
+
+    sal_Int32 nDays = ImpYearToDays(nYear);
+    for( sal_uInt16 i = 1; i < nMonth; i++ )
+        nDays += ImplDaysInMonth(i,nYear);
+    nDays += nDay;
+    return nDays;
+}
+
+static Date lcl_DaysToDate( sal_Int32 nDays )
+{
+    if ( nDays <= MIN_DAYS )
+        return Date( 1, 1, kYearMin );
+    if ( nDays >= MAX_DAYS )
+        return Date( 31, 12, kYearMax );
+
+    // Day 0 is -0001-12-31, day 1 is 0001-01-01
+    const sal_Int16 nSign = (nDays <= 0 ? -1 : 1);
+    sal_Int32 nTempDays;
+    sal_Int32 i = 0;
+    bool bCalc;
+
+    sal_Int16 nYear;
+    do
+    {
+        nYear = static_cast<sal_Int16>((nDays / 365) - (i * nSign));
+        if (nYear == 0)
+            nYear = nSign;
+        nTempDays = nDays - ImpYearToDays(nYear);
+        bCalc = false;
+        if ( nTempDays < 1 )
+        {
+            i += nSign;
+            bCalc = true;
+        }
+        else
+        {
+            if ( nTempDays > 365 )
+            {
+                if ( (nTempDays != 366) || !ImpIsLeapYear( nYear ) )
+                {
+                    i -= nSign;
+                    bCalc = true;
+                }
+            }
+        }
+    }
+    while ( bCalc );
+
+    sal_uInt16 nMonth = 1;
+    while ( nTempDays > ImplDaysInMonth( nMonth, nYear ) )
+    {
+        nTempDays -= ImplDaysInMonth( nMonth, nYear );
+        ++nMonth;
+    }
+
+    return Date( static_cast<sal_uInt16>(nTempDays), nMonth, nYear );
+}
+
+Date::Date( DateInitSystem )
+{
+    if ( !GetSystemDateTime( &mnDate, nullptr ) )
+        setDateFromDMY( 1, 1, 1900 );
+}
+
+Date::Date( const css::util::DateTime& rDateTime )
+{
+    setDateFromDMY( rDateTime.Day, rDateTime.Month, rDateTime.Year );
+}
+
+void Date::SetDay( sal_uInt16 nNewDay )
+{
+    setDateFromDMY( nNewDay, GetMonth(), GetYear() );
+}
+
+void Date::SetMonth( sal_uInt16 nNewMonth )
+{
+    setDateFromDMY( GetDay(), nNewMonth, GetYear() );
+}
+
+void Date::SetYear( sal_Int16 nNewYear )
+{
+    assert( nNewYear != 0 );
+    setDateFromDMY( GetDay(), GetMonth(), nNewYear );
+}
+
+void Date::AddYears( sal_Int16 nAddYears )
+{
+    sal_Int16 nYear = GetYear();
+    if (nYear < 0)
+    {
+        if (nAddYears < 0)
+        {
+            if (nYear < kYearMin - nAddYears)
+                nYear = kYearMin;
+            else
+                nYear += nAddYears;
+        }
+        else
+        {
+            nYear += nAddYears;
+            if (nYear == 0)
+                nYear = 1;
+        }
+    }
+    else
+    {
+        if (nAddYears > 0)
+        {
+            if (kYearMax - nAddYears < nYear)
+                nYear = kYearMax;
+            else
+                nYear += nAddYears;
+        }
+        else
+        {
+            nYear += nAddYears;
+            if (nYear == 0)
+                nYear = -1;
+        }
+    }
+
+    SetYear( nYear );
+    if (GetMonth() == 2 && GetDay() == 29 && !ImpIsLeapYear( nYear))
+        SetDay(28);
+}
+
+void Date::AddMonths( sal_Int32 nAddMonths )
+{
+    sal_Int32 nMonths = GetMonth() + nAddMonths;
+    sal_Int32 nNewMonth = nMonths % 12;
+    sal_Int32 nYear = GetYear() + nMonths / 12;
+    if( nMonths <= 0 || nNewMonth == 0 )
+        --nYear;
+    if( nNewMonth <= 0 )
+        nNewMonth += 12;
+    if (nYear == 0)
+        nYear = (nAddMonths < 0 ? -1 : 1);
+    else if (nYear < kYearMin)
+        nYear = kYearMin;
+    else if (nYear > kYearMax)
+        nYear = kYearMax;
+    SetMonth( static_cast<sal_uInt16>(nNewMonth) );
+    SetYear( static_cast<sal_Int16>(nYear) );
+    Normalize();
+}
+
+DayOfWeek Date::GetDayOfWeek() const
+{
+    return static_cast<DayOfWeek>((GetAsNormalizedDays()-1) % 7);
+}
+
+sal_uInt16 Date::GetDayOfYear() const
+{
+    sal_uInt16 nDay   = GetDay();
+    sal_uInt16 nMonth = GetMonth();
+    sal_Int16  nYear  = GetYear();
+    Normalize( nDay, nMonth, nYear);
+
+    for( sal_uInt16 i = 1; i < nMonth; i++ )
+         nDay += ::ImplDaysInMonth( i, nYear );
+    return nDay;
+}
+
+sal_uInt16 Date::GetWeekOfYear( DayOfWeek eStartDay,
+                                sal_Int16 nMinimumNumberOfDaysInWeek ) const
+{
+    short nWeek;
+    short n1WDay = static_cast<short>(Date( 1, 1, GetYear() ).GetDayOfWeek());
+    short nDayOfYear = static_cast<short>(GetDayOfYear());
+
+    // weekdays start at 0, thus decrement one
+    nDayOfYear--;
+    // account for StartDay
+    n1WDay = (n1WDay+(7-static_cast<short>(eStartDay))) % 7;
+
+    if (nMinimumNumberOfDaysInWeek < 1 || 7 < nMinimumNumberOfDaysInWeek)
+    {
+        SAL_WARN( "tools.datetime", "Date::GetWeekOfYear: invalid nMinimumNumberOfDaysInWeek" );
+        nMinimumNumberOfDaysInWeek = 4;
+    }
+
+    if ( nMinimumNumberOfDaysInWeek == 1 )
+    {
+        nWeek = ((n1WDay+nDayOfYear)/7) + 1;
+        // Set to 53rd week only if we're not in the
+        // first week of the new year
+        if ( nWeek == 54 )
+            nWeek = 1;
+        else if ( nWeek == 53 )
+        {
+            short nDaysInYear = static_cast<short>(GetDaysInYear());
+            short nDaysNextYear = static_cast<short>(Date( 1, 1, GetNextYear() ).GetDayOfWeek());
+            nDaysNextYear = (nDaysNextYear+(7-static_cast<short>(eStartDay))) % 7;
+            if ( nDayOfYear > (nDaysInYear-nDaysNextYear-1) )
+                nWeek = 1;
+        }
+    }
+    else if ( nMinimumNumberOfDaysInWeek == 7 )
+    {
+        nWeek = ((n1WDay+nDayOfYear)/7);
+        // First week of a year is equal to the last week of the previous year
+        if ( nWeek == 0 )
+        {
+            Date aLastDatePrevYear( 31, 12, GetPrevYear() );
+            nWeek = aLastDatePrevYear.GetWeekOfYear( eStartDay, nMinimumNumberOfDaysInWeek );
+        }
+    }
+    else // ( nMinimumNumberOfDaysInWeek == something_else, commentary examples for 4 )
+    {
+        // x_monday - thursday
+        if ( n1WDay < nMinimumNumberOfDaysInWeek )
+            nWeek = 1;
+        // Friday
+        else if ( n1WDay == nMinimumNumberOfDaysInWeek )
+            nWeek = 53;
+        // Saturday
+        else if ( n1WDay == nMinimumNumberOfDaysInWeek + 1 )
+        {
+            // Year after leap year
+            if ( Date( 1, 1, GetPrevYear() ).IsLeapYear() )
+                nWeek = 53;
+            else
+                nWeek = 52;
+        }
+        // Sunday
+        else
+            nWeek = 52;
+
+        if ( (nWeek == 1) || (nDayOfYear + n1WDay > 6) )
+        {
+            if ( nWeek == 1 )
+                nWeek += (nDayOfYear + n1WDay) / 7;
+            else
+                nWeek = (nDayOfYear + n1WDay) / 7;
+            if ( nWeek == 53 )
+            {
+                // next x_Sunday == first x_Sunday in the new year
+                // == still the same week!
+                sal_Int32 nTempDays = GetAsNormalizedDays();
+
+                nTempDays +=  6 - (GetDayOfWeek()+(7-static_cast<short>(eStartDay))) % 7;
+                nWeek = lcl_DaysToDate( nTempDays ).GetWeekOfYear( eStartDay, nMinimumNumberOfDaysInWeek );
+            }
+        }
+    }
+
+    return static_cast<sal_uInt16>(nWeek);
+}
+
+sal_uInt16 Date::GetDaysInMonth() const
+{
+    sal_uInt16 nDay   = GetDay();
+    sal_uInt16 nMonth = GetMonth();
+    sal_Int16  nYear  = GetYear();
+    Normalize( nDay, nMonth, nYear);
+
+    return ImplDaysInMonth( nMonth, nYear );
+}
+
+bool Date::IsLeapYear() const
+{
+    sal_Int16 nYear = GetYear();
+    return ImpIsLeapYear( nYear );
+}
+
+bool Date::IsValidAndGregorian() const
+{
+    sal_uInt16 nDay   = GetDay();
+    sal_uInt16 nMonth = GetMonth();
+    sal_Int16  nYear  = GetYear();
+
+    if ( !nMonth || (nMonth > 12) )
+        return false;
+    if ( !nDay || (nDay > ImplDaysInMonth( nMonth, nYear )) )
+        return false;
+    else if ( nYear <= 1582 )
+    {
+        if ( nYear < 1582 )
+            return false;
+        else if ( nMonth < 10 )
+            return false;
+        else if ( (nMonth == 10) && (nDay < 15) )
+            return false;
+    }
+
+    return true;
+}
+
+bool Date::IsValidDate() const
+{
+    return IsValidDate( GetDay(), GetMonth(), GetYear());
+}
+
+//static
+bool Date::IsValidDate( sal_uInt16 nDay, sal_uInt16 nMonth, sal_Int16 nYear )
+{
+    if (nYear == 0)
+        return false;
+    if ( !nMonth || (nMonth > 12) )
+        return false;
+    if ( !nDay || (nDay > ImplDaysInMonth( nMonth, nYear )) )
+        return false;
+    return true;
+}
+
+bool Date::IsEndOfMonth() const
+{
+    return IsEndOfMonth(GetDay(), GetMonth(), GetYear());
+}
+
+//static
+bool Date::IsEndOfMonth(sal_uInt16 nDay, sal_uInt16 nMonth, sal_Int16 nYear)
+{
+    return IsValidDate(nDay, nMonth, nYear) && ImplDaysInMonth(nMonth, nYear) == nDay;
+}
+
+void Date::Normalize()
+{
+    sal_uInt16 nDay   = GetDay();
+    sal_uInt16 nMonth = GetMonth();
+    sal_Int16  nYear  = GetYear();
+
+    if (!Normalize( nDay, nMonth, nYear))
+        return;
+
+    setDateFromDMY( nDay, nMonth, nYear );
+}
+
+//static
+bool Date::Normalize( sal_uInt16 & rDay, sal_uInt16 & rMonth, sal_Int16 & rYear )
+{
+    if (IsValidDate( rDay, rMonth, rYear))
+        return false;
+
+    if (rDay == 0 && rMonth == 0 && rYear == 0)
+        return false;   // empty date
+
+    if (rDay == 0)
+    {
+        if (rMonth == 0)
+            ;   // nothing, handled below
+        else
+            --rMonth;
+        // Last day of month is determined at the end.
+    }
+
+    if (rMonth > 12)
+    {
+        rYear += rMonth / 12;
+        rMonth = rMonth % 12;
+        if (rYear == 0)
+            rYear = 1;
+    }
+    if (rMonth == 0)
+    {
+        --rYear;
+        if (rYear == 0)
+            rYear = -1;
+        rMonth = 12;
+    }
+
+    if (rYear < 0)
+    {
+        sal_uInt16 nDays;
+        while (rDay > (nDays = ImplDaysInMonth( rMonth, rYear)))
+        {
+            rDay -= nDays;
+            if (rMonth > 1)
+                --rMonth;
+            else
+            {
+                if (rYear == kYearMin)
+                {
+                    rDay = 1;
+                    rMonth = 1;
+                    return true;
+                }
+                --rYear;
+                rMonth = 12;
+            }
+        }
+    }
+    else
+    {
+        sal_uInt16 nDays;
+        while (rDay > (nDays = ImplDaysInMonth( rMonth, rYear)))
+        {
+            rDay -= nDays;
+            if (rMonth < 12)
+                ++rMonth;
+            else
+            {
+                if (rYear == kYearMax)
+                {
+                    rDay = 31;
+                    rMonth = 12;
+                    return true;
+                }
+                ++rYear;
+                rMonth = 1;
+            }
+        }
+    }
+
+    if (rDay == 0)
+        rDay = ImplDaysInMonth( rMonth, rYear);
+
+    return true;
+}
+
+void Date::AddDays( sal_Int32 nDays )
+{
+    if (nDays != 0)
+        *this = lcl_DaysToDate( GetAsNormalizedDays() + nDays );
+}
+
+Date& Date::operator ++()
+{
+    *this = lcl_DaysToDate( GetAsNormalizedDays() + 1 );
+    return *this;
+}
+
+Date& Date::operator --()
+{
+    *this = lcl_DaysToDate( GetAsNormalizedDays() - 1 );
+    return *this;
+}
+
+Date operator +( const Date& rDate, sal_Int32 nDays )
+{
+    Date aDate( rDate );
+    aDate.AddDays( nDays );
+    return aDate;
+}
+
+Date operator -( const Date& rDate, sal_Int32 nDays )
+{
+    Date aDate( rDate );
+    aDate.AddDays( -nDays );
+    return aDate;
+}
+
+sal_Int32 operator -( const Date& rDate1, const Date& rDate2 )
+{
+    return rDate1.GetAsNormalizedDays() - rDate2.GetAsNormalizedDays();
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/tools/source/datetime/ttime.cxx b/tools/source/datetime/ttime.cxx
new file mode 100644
index 000000000..ee9e42720
--- /dev/null
+++ b/tools/source/datetime/ttime.cxx
@@ -0,0 +1,494 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+
+#include <algorithm>
+
+#if defined(_WIN32)
+#if !defined WIN32_LEAN_AND_MEAN
+# define WIN32_LEAN_AND_MEAN
+#endif
+#include <windows.h>
+#include <mmsystem.h>
+#elif defined UNX
+#include <sys/time.h>
+#include <unistd.h>
+#endif
+
+#include <time.h>
+#ifdef __MACH__
+#include <mach/clock.h>
+#include <mach/mach.h>
+#include <mach/mach_time.h>
+#endif
+
+#include <rtl/math.hxx>
+#include <tools/time.hxx>
+#include <com/sun/star/util/DateTime.hpp>
+
+#include <systemdatetime.hxx>
+
+#if defined(__sun) && defined(__GNUC__)
+extern long altzone;
+#endif
+
+namespace {
+
+    const sal_Int64 nanoSecInSec = 1000000000;
+    const sal_Int16 secInMin     = 60;
+    const sal_Int16 minInHour    = 60;
+
+    sal_Int64 TimeToNanoSec( const tools::Time& rTime )
+    {
+        short  nSign   = (rTime.GetTime() >= 0) ? +1 : -1;
+        sal_Int32   nHour    = rTime.GetHour();
+        sal_Int32   nMin     = rTime.GetMin();
+        sal_Int32   nSec     = rTime.GetSec();
+        sal_Int32   nNanoSec = rTime.GetNanoSec();
+
+        sal_Int64 nRet = nNanoSec;
+        nRet     +=            nSec * nanoSecInSec;
+        nRet     +=       nMin * secInMin * nanoSecInSec;
+        nRet     += nHour * minInHour * secInMin * nanoSecInSec;
+
+        return (nRet * nSign);
+    }
+
+    tools::Time NanoSecToTime( sal_Int64 nNanoSec )
+    {
+        short nSign;
+        if ( nNanoSec < 0 )
+        {
+            nNanoSec *= -1;
+            nSign = -1;
+        }
+        else
+            nSign = 1;
+
+        tools::Time aTime( 0, 0, 0, nNanoSec );
+        aTime.SetTime( aTime.GetTime() * nSign );
+        return aTime;
+    }
+
+} // anonymous namespace
+
+namespace tools {
+
+Time::Time( TimeInitSystem )
+{
+    if ( !GetSystemDateTime( nullptr, &nTime ) )
+        nTime = 0;
+}
+
+Time::Time( const tools::Time& rTime )
+{
+    nTime = rTime.nTime;
+}
+
+Time::Time( sal_uInt32 nHour, sal_uInt32 nMin, sal_uInt32 nSec, sal_uInt64 nNanoSec )
+{
+    init(nHour, nMin, nSec, nNanoSec);
+}
+Time::Time( const css::util::Time &_rTime )
+{
+    init(_rTime.Hours, _rTime.Minutes, _rTime.Seconds, _rTime.NanoSeconds);
+}
+Time::Time( const css::util::DateTime &_rDateTime )
+{
+    init(_rDateTime.Hours, _rDateTime.Minutes, _rDateTime.Seconds, _rDateTime.NanoSeconds);
+}
+
+void tools::Time::init( sal_uInt32 nHour, sal_uInt32 nMin, sal_uInt32 nSec, sal_uInt64 nNanoSec )
+{
+    // normalize time
+    nSec     += nNanoSec / nanoSecInSec;
+    nNanoSec %= nanoSecInSec;
+    nMin     += nSec / secInMin;
+    nSec     %= secInMin;
+    nHour    += nMin / minInHour;
+    nMin     %= minInHour;
+
+    // construct time
+    nTime = nNanoSec +
+            nSec  * SEC_MASK +
+            nMin  * MIN_MASK +
+            nHour * HOUR_MASK;
+}
+
+void tools::Time::SetHour( sal_uInt16 nNewHour )
+{
+    short  nSign          = (nTime >= 0) ? +1 : -1;
+    sal_Int32   nMin      = GetMin();
+    sal_Int32   nSec      = GetSec();
+    sal_Int32   nNanoSec  = GetNanoSec();
+
+    nTime = nSign *
+            ( nNanoSec +
+              nSec  * SEC_MASK +
+              nMin  * MIN_MASK +
+              nNewHour * HOUR_MASK );
+}
+
+void tools::Time::SetMin( sal_uInt16 nNewMin )
+{
+    short  nSign          = (nTime >= 0) ? +1 : -1;
+    sal_Int32   nHour     = GetHour();
+    sal_Int32   nSec      = GetSec();
+    sal_Int32   nNanoSec  = GetNanoSec();
+
+    // no overflow
+    nNewMin = nNewMin % minInHour;
+
+    nTime = nSign *
+            ( nNanoSec +
+              nSec  * SEC_MASK +
+              nNewMin  * MIN_MASK +
+              nHour * HOUR_MASK );
+}
+
+void tools::Time::SetSec( sal_uInt16 nNewSec )
+{
+    short       nSign     = (nTime >= 0) ? +1 : -1;
+    sal_Int32   nHour     = GetHour();
+    sal_Int32   nMin      = GetMin();
+    sal_Int32   nNanoSec   = GetNanoSec();
+
+    // no overflow
+    nNewSec = nNewSec % secInMin;
+
+    nTime = nSign *
+            ( nNanoSec +
+              nNewSec  * SEC_MASK +
+              nMin  * MIN_MASK +
+              nHour * HOUR_MASK );
+}
+
+void tools::Time::SetNanoSec( sal_uInt32 nNewNanoSec )
+{
+    short       nSign     = (nTime >= 0) ? +1 : -1;
+    sal_Int32   nHour     = GetHour();
+    sal_Int32   nMin      = GetMin();
+    sal_Int32   nSec      = GetSec();
+
+    // no overflow
+    nNewNanoSec = nNewNanoSec % nanoSecInSec;
+
+    nTime = nSign *
+            ( nNewNanoSec +
+              nSec  * SEC_MASK +
+              nMin  * MIN_MASK +
+              nHour * HOUR_MASK );
+}
+
+sal_Int64 tools::Time::GetNSFromTime() const
+{
+    short       nSign     = (nTime >= 0) ? +1 : -1;
+    sal_Int32   nHour     = GetHour();
+    sal_Int32   nMin      = GetMin();
+    sal_Int32   nSec      = GetSec();
+    sal_Int32   nNanoSec  = GetNanoSec();
+
+    return nSign *
+           ( nNanoSec +
+             nSec  * nanoSecInSec +
+             nMin  * (secInMin * nanoSecInSec) +
+             nHour * (minInHour * secInMin * nanoSecInSec) );
+}
+
+void tools::Time::MakeTimeFromNS( sal_Int64 nNS )
+{
+    short nSign;
+    if ( nNS < 0 )
+    {
+        nNS *= -1;
+        nSign = -1;
+    }
+    else
+        nSign = 1;
+
+    // avoid overflow when sal_uIntPtr is 32 bits
+    tools::Time aTime( 0, 0, nNS/nanoSecInSec, nNS % nanoSecInSec );
+    SetTime( aTime.GetTime() * nSign );
+}
+
+sal_Int32 tools::Time::GetMSFromTime() const
+{
+    short       nSign     = (nTime >= 0) ? +1 : -1;
+    sal_Int32   nHour     = GetHour();
+    sal_Int32   nMin      = GetMin();
+    sal_Int32   nSec      = GetSec();
+    sal_Int32   nNanoSec  = GetNanoSec();
+
+    return nSign *
+           ( nNanoSec/1000000 +
+             nSec  * 1000 +
+             nMin  * 60000 +
+             nHour * 3600000 );
+}
+
+void tools::Time::MakeTimeFromMS( sal_Int32 nMS )
+{
+    short nSign;
+    if ( nMS < 0 )
+    {
+        nMS *= -1;
+        nSign = -1;
+    }
+    else
+        nSign = 1;
+
+    // avoid overflow when sal_uIntPtr is 32 bits
+    tools::Time aTime( 0, 0, nMS/1000, (nMS % 1000) * 1000000 );
+    SetTime( aTime.GetTime() * nSign );
+}
+
+double tools::Time::GetTimeInDays() const
+{
+    short  nSign      = (nTime >= 0) ? +1 : -1;
+    double nHour      = GetHour();
+    double nMin       = GetMin();
+    double nSec       = GetSec();
+    double nNanoSec   = GetNanoSec();
+
+    return (nHour + (nMin / 60) + (nSec / (minInHour * secInMin)) + (nNanoSec / (minInHour * secInMin * nanoSecInSec))) / 24 * nSign;
+}
+
+// static
+void tools::Time::GetClock( double fTimeInDays,
+                            sal_uInt16& nHour, sal_uInt16& nMinute, sal_uInt16& nSecond,
+                            double& fFractionOfSecond, int nFractionDecimals )
+{
+    const double fTime = fTimeInDays - rtl::math::approxFloor(fTimeInDays); // date part absent
+
+    // If 0 then full day (or no day), shortcut.
+    // If < 0 then approxFloor() effectively returned the ceiling (note this
+    // also holds for negative fTimeInDays values) because of a near identical
+    // value, shortcut this to a full day as well.
+    // If >= 1.0 (actually == 1.0) then fTimeInDays is a negative small value
+    // not significant for a representable time and approxFloor() returned -1,
+    // shortcut to 0:0:0, otherwise it would become 24:0:0.
+    if (fTime <= 0.0 || fTime >= 1.0)
+    {
+        nHour = nMinute = nSecond = 0;
+        fFractionOfSecond = 0.0;
+        return;
+    }
+
+    // In seconds, including milli and nano.
+    const double fRawSeconds = fTime * tools::Time::secondPerDay;
+
+    // Round to nanoseconds most, which is the highest resolution this could be
+    // influenced by, but if the original value included a date round to at
+    // most 14 significant digits (including adding 4 for *86400), otherwise we
+    // might end up with a fake precision of h:m:s.999999986 which in fact
+    // should had been h:m:s+1
+    // BUT, leave at least 2 decimals to round. Which shouldn't be a problem in
+    // practice because class Date can calculate only 8-digit days for it's
+    // sal_Int16 year range, which exactly leaves us with 14-4-8=2.
+    int nDec = 9;
+    const double fAbsTimeInDays = fabs( fTimeInDays);
+    if (fAbsTimeInDays >= 1.0)
+    {
+        const int nDig = static_cast<int>(ceil( log10( fAbsTimeInDays)));
+        nDec = std::clamp( 10 - nDig, 2, 9 );
+    }
+    double fSeconds = rtl::math::round( fRawSeconds, nDec);
+
+    // If this ended up as a full day the original value was very very close
+    // but not quite. Take that.
+    if (fSeconds >= tools::Time::secondPerDay)
+        fSeconds = fRawSeconds;
+
+    // Now do not round values (specifically not up), but truncate to the next
+    // magnitude, so 23:59:59.99 is still 23:59:59 and not 24:00:00 (or even
+    // 00:00:00 which Excel does).
+    nHour = fSeconds / tools::Time::secondPerHour;
+    fSeconds -= nHour * tools::Time::secondPerHour;
+    nMinute = fSeconds / tools::Time::secondPerMinute;
+    fSeconds -= nMinute * tools::Time::secondPerMinute;
+    nSecond = fSeconds;
+    fSeconds -= nSecond;
+
+    assert(fSeconds < 1.0);     // or back to the drawing board...
+
+    if (nFractionDecimals > 0)
+    {
+        // Do not simply round the fraction, otherwise .999 would end up as .00
+        // again. Truncate instead if rounding would round up into an integer
+        // value.
+        fFractionOfSecond = rtl::math::round( fSeconds, nFractionDecimals);
+        if (fFractionOfSecond >= 1.0)
+            fFractionOfSecond = rtl::math::pow10Exp( std::trunc(
+                        rtl::math::pow10Exp( fSeconds, nFractionDecimals)), -nFractionDecimals);
+    }
+    else
+        fFractionOfSecond = fSeconds;
+}
+
+Time& tools::Time::operator =( const tools::Time& rTime )
+{
+    nTime = rTime.nTime;
+    return *this;
+}
+
+Time& tools::Time::operator +=( const tools::Time& rTime )
+{
+    nTime = NanoSecToTime( TimeToNanoSec( *this ) +
+                           TimeToNanoSec( rTime ) ).GetTime();
+    return *this;
+}
+
+Time& tools::Time::operator -=( const tools::Time& rTime )
+{
+    nTime = NanoSecToTime( TimeToNanoSec( *this ) -
+                           TimeToNanoSec( rTime ) ).GetTime();
+    return *this;
+}
+
+Time operator +( const tools::Time& rTime1, const tools::Time& rTime2 )
+{
+    return NanoSecToTime( TimeToNanoSec( rTime1 ) +
+                          TimeToNanoSec( rTime2 ) );
+}
+
+Time operator -( const tools::Time& rTime1, const tools::Time& rTime2 )
+{
+    return NanoSecToTime( TimeToNanoSec( rTime1 ) -
+                          TimeToNanoSec( rTime2 ) );
+}
+
+bool tools::Time::IsEqualIgnoreNanoSec( const tools::Time& rTime ) const
+{
+    sal_Int32 n1 = (nTime       < 0 ? -static_cast<sal_Int32>(GetNanoSec())       : GetNanoSec() );
+    sal_Int32 n2 = (rTime.nTime < 0 ? -static_cast<sal_Int32>(rTime.GetNanoSec()) : rTime.GetNanoSec() );
+    return (nTime - n1) == (rTime.nTime - n2);
+}
+
+Time tools::Time::GetUTCOffset()
+{
+#if defined(_WIN32)
+    TIME_ZONE_INFORMATION   aTimeZone;
+    aTimeZone.Bias = 0;
+    DWORD nTimeZoneRet = GetTimeZoneInformation( &aTimeZone );
+    sal_Int32 nTempTime = aTimeZone.Bias;
+    if ( nTimeZoneRet == TIME_ZONE_ID_STANDARD )
+        nTempTime += aTimeZone.StandardBias;
+    else if ( nTimeZoneRet == TIME_ZONE_ID_DAYLIGHT )
+        nTempTime += aTimeZone.DaylightBias;
+    tools::Time aTime( 0, static_cast<sal_uInt16>(abs( nTempTime )) );
+    if ( nTempTime > 0 )
+        aTime = -aTime;
+    return aTime;
+#else
+    static sal_uInt64   nCacheTicks = 0;
+    static sal_Int32    nCacheSecOffset = -1;
+    sal_uInt64          nTicks = tools::Time::GetSystemTicks();
+    time_t          nTime;
+    tm              aTM;
+    short           nTempTime;
+
+    // determine value again if needed
+    if ( (nCacheSecOffset == -1)            ||
+         ((nTicks - nCacheTicks) > 360000)  ||
+         ( nTicks < nCacheTicks ) // handle overflow
+         )
+    {
+        nTime = time( nullptr );
+        localtime_r( &nTime, &aTM );
+        sal_Int32 nLocalTime = mktime( &aTM );
+#if defined(__sun)
+        // Solaris gmtime_r() seems not to handle daylight saving time
+        // flags correctly
+        nUTC = nLocalTime + ( aTM.tm_isdst == 0 ? timezone : altzone );
+#elif defined( LINUX )
+        // Linux mktime() seems not to handle tm_isdst correctly
+        sal_Int32 nUTC = nLocalTime - aTM.tm_gmtoff;
+#else
+        gmtime_r( &nTime, &aTM );
+        sal_Int32 nUTC = mktime( &aTM );
+#endif
+        nCacheTicks = nTicks;
+        nCacheSecOffset = (nLocalTime-nUTC) / 60;
+    }
+
+    nTempTime = abs( nCacheSecOffset );
+    tools::Time aTime( 0, static_cast<sal_uInt16>(nTempTime) );
+    if ( nCacheSecOffset < 0 )
+        aTime = -aTime;
+    return aTime;
+#endif
+}
+
+sal_uInt64 tools::Time::GetSystemTicks()
+{
+    return tools::Time::GetMonotonicTicks() / 1000;
+}
+
+#ifdef _WIN32
+static LARGE_INTEGER initPerformanceFrequency()
+{
+    LARGE_INTEGER nTicksPerSecond = { 0, 0 };
+    if (!QueryPerformanceFrequency(&nTicksPerSecond))
+        nTicksPerSecond.QuadPart = 0;
+    return nTicksPerSecond;
+}
+#endif
+
+sal_uInt64 tools::Time::GetMonotonicTicks()
+{
+#ifdef _WIN32
+    static const LARGE_INTEGER nTicksPerSecond = initPerformanceFrequency();
+    if (nTicksPerSecond.QuadPart > 0)
+    {
+        LARGE_INTEGER nPerformanceCount;
+        QueryPerformanceCounter(&nPerformanceCount);
+        return static_cast<sal_uInt64>(
+            ( nPerformanceCount.QuadPart * 1000 * 1000 ) / nTicksPerSecond.QuadPart );
+    }
+    else
+    {
+        return static_cast<sal_uInt64>( timeGetTime() * 1000 );
+    }
+#else
+    sal_uInt64 nMicroSeconds;
+#ifdef __MACH__
+    static mach_timebase_info_data_t info = { 0, 0 };
+    if ( 0 == info.numer )
+        mach_timebase_info( &info );
+    nMicroSeconds = mach_absolute_time() * static_cast<double>(info.numer / info.denom) / 1000;
+#else
+#if defined(_POSIX_TIMERS)
+    struct timespec currentTime;
+    clock_gettime( CLOCK_MONOTONIC, &currentTime );
+    nMicroSeconds
+        = static_cast<sal_uInt64>(currentTime.tv_sec) * 1000 * 1000 + currentTime.tv_nsec / 1000;
+#else
+    struct timeval currentTime;
+    gettimeofday( &currentTime, nullptr );
+    nMicroSeconds = static_cast<sal_uInt64>(currentTime.tv_sec) * 1000 * 1000 + currentTime.tv_usec;
+#endif
+#endif // __MACH__
+    return nMicroSeconds;
+#endif // _WIN32
+}
+
+} /* namespace tools */
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */