source: XMLIO_V2/external/src/POCO/Foundation.save/LocalDateTime.cpp @ 80

//
// LocalDateTime.cpp
//
// $Id: //poco/1.3/Foundation/src/LocalDateTime.cpp#6 $
//
// Library: Foundation
// Package: DateTime
// Module:  LocalDateTime
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
// 
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//


#include "Poco/LocalDateTime.h"
#include "Poco/Timezone.h"
#include "Poco/Timespan.h"
#include "Poco/Exception.h"
#include <algorithm>
#include <ctime>


namespace Poco {


LocalDateTime::LocalDateTime()
{
        determineTzd(true);
}


LocalDateTime::LocalDateTime(int year, int month, int day, int hour, int minute, int second, int millisecond, int microsecond):
        _dateTime(year, month, day, hour, minute, second, millisecond, microsecond)
{
        determineTzd();
}


LocalDateTime::LocalDateTime(int tzd, int year, int month, int day, int hour, int minute, int second, int millisecond, int microsecond):
        _dateTime(year, month, day, hour, minute, second, millisecond, microsecond),
        _tzd(tzd)
{
}


LocalDateTime::LocalDateTime(double julianDay):
        _dateTime(julianDay)
{
        determineTzd(true);
}


LocalDateTime::LocalDateTime(int tzd, double julianDay):
        _dateTime(julianDay),
        _tzd(tzd)
{
        adjustForTzd();
}


LocalDateTime::LocalDateTime(const DateTime& dateTime):
        _dateTime(dateTime)
{
        determineTzd(true);
}


LocalDateTime::LocalDateTime(int tzd, const DateTime& dateTime):
        _dateTime(dateTime),
        _tzd(tzd)
{
        adjustForTzd();
}


LocalDateTime::LocalDateTime(int tzd, const DateTime& dateTime, bool adjust):
        _dateTime(dateTime),
        _tzd(tzd)
{
        if (adjust)
                adjustForTzd();
}


LocalDateTime::LocalDateTime(const LocalDateTime& dateTime):
        _dateTime(dateTime._dateTime),
        _tzd(dateTime._tzd)
{
}


LocalDateTime::LocalDateTime(Timestamp::UtcTimeVal utcTime, Timestamp::TimeDiff diff, int tzd):
        _dateTime(utcTime, diff),
        _tzd(tzd)
{
        adjustForTzd();
}

        
LocalDateTime::~LocalDateTime()
{
}


LocalDateTime& LocalDateTime::operator = (const LocalDateTime& dateTime)
{
        if (&dateTime != this)
        {
                _dateTime = dateTime._dateTime;
                _tzd      = dateTime._tzd;
        }
        return *this;
}


LocalDateTime& LocalDateTime::operator = (const Timestamp& timestamp)
{
        if (timestamp != this->timestamp())
        {
                _dateTime = timestamp;
                determineTzd(true);
        }
        return *this;
}


LocalDateTime& LocalDateTime::operator = (double julianDay)
{
        _dateTime = julianDay;
        determineTzd(true);
        return *this;
}


LocalDateTime& LocalDateTime::assign(int year, int month, int day, int hour, int minute, int second, int millisecond, int microseconds)
{
        _dateTime.assign(year, month, day, hour, minute, second, millisecond, microseconds);
        determineTzd(false);
        return *this;
}


LocalDateTime& LocalDateTime::assign(int tzd, int year, int month, int day, int hour, int minute, int second, int millisecond, int microseconds)
{
        _dateTime.assign(year, month, day, hour, minute, second, millisecond, microseconds);
        _tzd = tzd;
        return *this;
}


LocalDateTime& LocalDateTime::assign(int tzd, double julianDay)
{
        _tzd      = tzd;
        _dateTime = julianDay;
        adjustForTzd();
        return *this;
}


void LocalDateTime::swap(LocalDateTime& dateTime)
{
        _dateTime.swap(dateTime._dateTime);
        std::swap(_tzd, dateTime._tzd);
}


DateTime LocalDateTime::utc() const
{
        return DateTime(_dateTime.utcTime(), -((Timestamp::TimeDiff) _tzd)*Timespan::SECONDS);
}


bool LocalDateTime::operator == (const LocalDateTime& dateTime) const
{
        return utcTime() == dateTime.utcTime();
}


bool LocalDateTime::operator != (const LocalDateTime& dateTime) const   
{
        return utcTime() != dateTime.utcTime();
}


bool LocalDateTime::operator <  (const LocalDateTime& dateTime) const   
{
        return utcTime() < dateTime.utcTime();
}


bool LocalDateTime::operator <= (const LocalDateTime& dateTime) const   
{
        return utcTime() <= dateTime.utcTime();
}


bool LocalDateTime::operator >  (const LocalDateTime& dateTime) const   
{
        return utcTime() > dateTime.utcTime();
}


bool LocalDateTime::operator >= (const LocalDateTime& dateTime) const   
{
        return utcTime() >= dateTime.utcTime();
}


LocalDateTime LocalDateTime::operator + (const Timespan& span) const
{
        // First calculate the adjusted UTC time, then calculate the
        // locally adjusted time by constructing a new LocalDateTime.
        DateTime tmp(utcTime(), span.totalMicroseconds());
        return LocalDateTime(tmp);
}


LocalDateTime LocalDateTime::operator - (const Timespan& span) const
{
        // First calculate the adjusted UTC time, then calculate the
        // locally adjusted time by constructing a new LocalDateTime.
        DateTime tmp(utcTime(), -span.totalMicroseconds());
        return LocalDateTime(tmp);
}


Timespan LocalDateTime::operator - (const LocalDateTime& dateTime) const
{
        return Timespan((utcTime() - dateTime.utcTime())/10);
}


LocalDateTime& LocalDateTime::operator += (const Timespan& span)
{
        // Use the same trick as in operator+. Create a UTC time, adjust
        // it for the span, and convert back to LocalDateTime. This will
        // recalculate the tzd correctly in the case where the addition
        // crosses a DST boundary.
        *this = DateTime(utcTime(), span.totalMicroseconds());
        return *this;
}


LocalDateTime& LocalDateTime::operator -= (const Timespan& span)
{
        // Use the same trick as in operator-. Create a UTC time, adjust
        // it for the span, and convert back to LocalDateTime. This will
        // recalculate the tzd correctly in the case where the subtraction
        // crosses a DST boundary.
        *this = DateTime(utcTime(), -span.totalMicroseconds());
        return *this;
}


void LocalDateTime::determineTzd(bool adjust)
{
        if (adjust)
        {
                std::time_t epochTime = _dateTime.timestamp().epochTime();
#if defined(_WIN32) || defined(POCO_NO_POSIX_TSF)
                std::tm* broken = std::localtime(&epochTime);
                if (!broken) throw Poco::SystemException("cannot get local time");
                _tzd = (Timezone::utcOffset() + ((broken->tm_isdst == 1) ? 3600 : 0));
#else
                std::tm broken;
                if (!localtime_r(&epochTime, &broken))
                        throw Poco::SystemException("cannot get local time");
                _tzd = (Timezone::utcOffset() + ((broken.tm_isdst == 1) ? 3600 : 0));
#endif
                adjustForTzd();
        }
        else
        {
                int dst;
                dstOffset(dst);
                _tzd = (Timezone::utcOffset() + dst);
        }
}


std::time_t LocalDateTime::dstOffset(int& dstOffset) const
{
        std::time_t local;
        std::tm     broken;

        broken.tm_year  = (_dateTime.year() - 1900);
        broken.tm_mon   = (_dateTime.month() - 1);
        broken.tm_mday  = _dateTime.day();
        broken.tm_hour  = _dateTime.hour();
        broken.tm_min   = _dateTime.minute();
        broken.tm_sec   = _dateTime.second();
        broken.tm_isdst = -1;
        local = std::mktime(&broken);
        
        dstOffset = (broken.tm_isdst == 1) ? 3600 : 0;
        return local;
}


} // namespace Poco