src/main/cpp/timezone.cpp

/*
 * 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
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#if defined(_MSC_VER)
    #pragma warning ( disable: 4231 4251 4275 4786 )
#endif


#define __STDC_CONSTANT_MACROS
#include <log4cxx/logstring.h>
#include <log4cxx/helpers/timezone.h>
#include <stdlib.h>

#include <apr_time.h>
#include <apr_pools.h>
#include <apr_strings.h>
#include <log4cxx/helpers/transcoder.h>
#include <log4cxx/helpers/stringhelper.h>
#include <log4cxx/helpers/pool.h>
#include <log4cxx/logger.h>

using namespace log4cxx;
using namespace log4cxx::helpers;

IMPLEMENT_LOG4CXX_OBJECT( TimeZone )

namespace log4cxx
{
namespace helpers
{
namespace TimeZoneImpl
{
/** Time zone object that represents GMT. */
class GMTTimeZone : public TimeZone
{
    public:
        /** Class factory. */
        static const TimeZonePtr& getInstance()
        {
            static TimeZonePtr tz( new GMTTimeZone() );
            return tz;
        }

        /** Explode time to human readable form. */
        log4cxx_status_t explode( apr_time_exp_t* result, log4cxx_time_t input ) const
        {
            apr_status_t stat;

            //  APR 1.1 and early mishandles microseconds on dates
            //   before 1970, APR bug 32520
            if (LOG4CXX_UNLIKELY(input < 0 && apr_time_usec(input) < 0))
            {
                apr_time_t floorTime = (apr_time_sec(input) - 1) * APR_USEC_PER_SEC;
                stat = apr_time_exp_gmt(result, floorTime);
                result->tm_usec = (int) (input - floorTime);
            }
            else
            {
                stat = apr_time_exp_gmt( result, input );
            }

            return stat;
        }

    private:
        GMTTimeZone() : TimeZone( LOG4CXX_STR("GMT") )
        {
        }
};



/** Time zone object that represents GMT. */
class LocalTimeZone : public TimeZone
{
    public:
        /** Class factory. */
        static const TimeZonePtr& getInstance()
        {
            static TimeZonePtr tz( new LocalTimeZone() );
            return tz;
        }

        /** Explode time to human readable form. */
        log4cxx_status_t explode( apr_time_exp_t* result, log4cxx_time_t input ) const
        {
            apr_status_t stat;

            //  APR 1.1 and early mishandles microseconds on dates
            //   before 1970, APR bug 32520
            if (LOG4CXX_UNLIKELY(input < 0 && apr_time_usec(input) < 0))
            {
                apr_time_t floorTime = (apr_time_sec(input) - 1) * APR_USEC_PER_SEC;
                stat = apr_time_exp_lt(result, floorTime);
                result->tm_usec = (int) (input - floorTime);
            }
            else
            {
                stat = apr_time_exp_lt( result, input );
            }

            return stat;
        }


    private:
        LocalTimeZone() : TimeZone( getTimeZoneName() )
        {
        }

        static const LogString getTimeZoneName()
        {
            const int MAX_TZ_LENGTH = 255;
            char tzName[MAX_TZ_LENGTH];
            apr_size_t tzLength;
            apr_time_exp_t tm;
            apr_time_exp_lt(&tm, 0);
            apr_strftime(tzName, &tzLength, MAX_TZ_LENGTH, "%Z", &tm);

            if (tzLength == 0)
            {
                apr_strftime(tzName, &tzLength, MAX_TZ_LENGTH, "%z", &tm);
            }

            tzName[tzLength] = 0;
            LogString retval;
            log4cxx::helpers::Transcoder::decode(tzName, retval);
            return retval;
        }

};



/** Time zone object that represents a fixed offset from GMT. */
class FixedTimeZone : public TimeZone
{
    public:
        FixedTimeZone( const LogString& name, apr_int32_t offset1 ) : TimeZone( name ), offset( offset1 )
        {
        }

        /** Explode time to human readable form. */
        log4cxx_status_t explode( apr_time_exp_t* result, log4cxx_time_t input ) const
        {
            apr_status_t stat;

            //  APR 1.1 and early mishandles microseconds on dates
            //   before 1970, APR bug 32520
            if (LOG4CXX_UNLIKELY(input < 0 && apr_time_usec(input) < 0))
            {
                apr_time_t floorTime = (apr_time_sec(input) - 1) * APR_USEC_PER_SEC;
                stat = apr_time_exp_tz(result, floorTime, offset);
                result->tm_usec = (int) (input - floorTime);
            }
            else
            {
                stat = apr_time_exp_tz( result, input, offset );
            }

            return stat;
        }


    private:
        const apr_int32_t offset;
};

}
}
}



TimeZone::TimeZone( const LogString& id1 ) : id( id1 )
{
}

TimeZone::~TimeZone()
{
}

const TimeZonePtr& TimeZone::getDefault()
{
    return log4cxx::helpers::TimeZoneImpl::LocalTimeZone::getInstance();
}

const TimeZonePtr& TimeZone::getGMT()
{
    return log4cxx::helpers::TimeZoneImpl::GMTTimeZone::getInstance();
}

const TimeZonePtr TimeZone::getTimeZone( const LogString& id )
{
    const logchar gmt[] = { 0x47, 0x4D, 0x54, 0 };

    if ( id == gmt )
    {
        return log4cxx::helpers::TimeZoneImpl::GMTTimeZone::getInstance();
    }

    if ( id.length() >= 5 && id.substr( 0, 3 ) == gmt )
    {
        int hours = 0;
        int minutes = 0;
        int sign = 1;

        if (id[3] == 0x2D /* '-' */)
        {
            sign = -1;
        }

        LogString off( id.substr( 4 ) );

        if ( id.length() >= 7 )
        {
            size_t colonPos = off.find( 0x3A /* ':' */);

            if ( colonPos == LogString::npos )
            {
                minutes = StringHelper::toInt(off.substr(off.length() - 2));
                hours = StringHelper::toInt(off.substr(0, off.length() - 2));
            }
            else
            {
                minutes = StringHelper::toInt(off.substr(colonPos + 1));
                hours = StringHelper::toInt(off.substr(0, colonPos));
            }
        }
        else
        {
            hours = StringHelper::toInt(off);
        }

        LogString s(gmt);
        Pool p;
        LogString hh;
        StringHelper::toString(hours, p, hh);

        if (sign > 0)
        {
            s.append(1, (logchar) 0x2B /* '+' */);
        }
        else
        {
            s.append(1, (logchar) 0x2D /* '-' */);
        }

        if (hh.length() == 1)
        {
            s.append(1, (logchar) 0x30 /* '0' */);
        }

        s.append(hh);
        s.append(1, (logchar) 0x3A /*' :' */);
        LogString mm;
        StringHelper::toString(minutes, p, mm);

        if (mm.length() == 1)
        {
            s.append(1, (logchar) 0x30 /* '0' */);
        }

        s.append(mm);
        apr_int32_t offset = sign * (hours * 3600 + minutes * 60);
        return new log4cxx::helpers::TimeZoneImpl::FixedTimeZone( s, offset );
    }

    const TimeZonePtr& ltz = getDefault();

    if ( ltz->getID() == id )
    {
        return ltz;
    }

    return getGMT();
}