/usr/include/boost/date_time
Edit: /usr/include/boost/date_time/c_local_time_adjustor.hpp (2631B)
#ifndef DATE_TIME_C_LOCAL_TIME_ADJUSTOR_HPP__
#define DATE_TIME_C_LOCAL_TIME_ADJUSTOR_HPP__
/* Copyright (c) 2002,2003,2005 CrystalClear Software, Inc.
* Use, modification and distribution is subject to the
* Boost Software License, Version 1.0. (See accompanying
* file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
* Author: Jeff Garland, Bart Garst
* $Date$
*/
/*! @file c_local_time_adjustor.hpp
Time adjustment calculations based on machine
*/
#include
#include
#include
#include
#include
namespace boost {
namespace date_time {
//! Adjust to / from utc using the C API
/*! Warning!!! This class assumes that timezone settings of the
* machine are correct. This can be a very dangerous assumption.
*/
template
class c_local_adjustor {
public:
typedef typename time_type::time_duration_type time_duration_type;
typedef typename time_type::date_type date_type;
typedef typename date_type::duration_type date_duration_type;
//! Convert a utc time to local time
static time_type utc_to_local(const time_type& t)
{
date_type time_t_start_day(1970,1,1);
time_type time_t_start_time(time_t_start_day,time_duration_type(0,0,0));
if (t < time_t_start_time) {
boost::throw_exception(std::out_of_range("Cannot convert dates prior to Jan 1, 1970"));
BOOST_DATE_TIME_UNREACHABLE_EXPRESSION(return time_t_start_time); // should never reach
}
date_duration_type dd = t.date() - time_t_start_day;
time_duration_type td = t.time_of_day();
uint64_t t2 = static_cast(dd.days())*86400 +
static_cast(td.hours())*3600 +
static_cast(td.minutes())*60 +
td.seconds();
// detect y2038 issue and throw instead of proceed with bad time
std::time_t tv = boost::numeric_cast(t2);
std::tm tms, *tms_ptr;
tms_ptr = c_time::localtime(&tv, &tms);
date_type d(static_cast(tms_ptr->tm_year + 1900),
static_cast(tms_ptr->tm_mon + 1),
static_cast(tms_ptr->tm_mday));
time_duration_type td2(tms_ptr->tm_hour,
tms_ptr->tm_min,
tms_ptr->tm_sec,
t.time_of_day().fractional_seconds());
return time_type(d,td2);
}
};
} } //namespace date_time
#endif