bugfixed erase and re-set of TTLs; changed time warp thresh from 24h to 10mins

[pingcheck] / src / dns / timetolive.cpp

/*
The software in this package is distributed under the GNU General
Public License version 2 (with a special exception described below).

A copy of GNU General Public License (GPL) is included in this distribution,
in the file COPYING.GPL.

As a special exception, if other files instantiate templates or use macros
or inline functions from this file, or you compile this file and link it
with other works to produce a work based on this file, this file
does not by itself cause the resulting work to be covered
by the GNU General Public License.

However the source code for this file must still be made available
in accordance with section (3) of the GNU General Public License.

This exception does not invalidate any other reasons why a work based
on this file might be covered by the GNU General Public License.
*/
#include "dns/timetolive.h"

#include "boost_assert_handler.h"

using boost::date_time::time_resolution_traits_adapted64_impl;
using boost::posix_time::microsec_clock;
using boost::posix_time::ptime;

//-----------------------------------------------------------------------------
// TimeToLive
//-----------------------------------------------------------------------------

TimeToLive::TimeToLive( uint32_t ttl ) :
    Ttl( ttl ),
    TtlSetTime( microsec_clock::universal_time() )
{
}

TimeToLive::~TimeToLive()
{
}

/**
 * @return the original time-to-live value, as specified by the set method.
 */
uint32_t TimeToLive::get_value() const
{
    return Ttl;
}

/**
 * @param ttl the time-to-live value.
 */
void TimeToLive::set_value( const uint32_t ttl )
{
    BOOST_ASSERT( 0 <= ttl );

    Ttl = ttl;
    TtlSetTime = microsec_clock::universal_time();
}

/**
 * @return the value of the time-to-live updated since the last set was called.
 */
uint32_t TimeToLive::get_updated_value() const
{
    ptime now = microsec_clock::universal_time();
    uint32_t elapsed_seconds = static_cast<uint32_t>(
            (now - TtlSetTime).total_seconds()
    );

    uint32_t original_ttl = get_value();
    if (elapsed_seconds > original_ttl)
        return 0;
    else
        return original_ttl - elapsed_seconds;
}

bool TimeToLive::was_set_before(const ptime &threshold) const
{
    return TtlSetTime < threshold;
}