| #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: 2008-11-12 14:37:53 -0500 (Wed, 12 Nov 2008) $ |
| */ |
| |
| /*! @file c_local_time_adjustor.hpp |
| Time adjustment calculations based on machine |
| */ |
| |
| #include <stdexcept> |
| #include <boost/throw_exception.hpp> |
| #include <boost/date_time/compiler_config.hpp> |
| #include <boost/date_time/c_time.hpp> |
| |
| 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 time_type> |
| 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(); |
| std::time_t t2 = dd.days()*86400 + td.hours()*3600 + td.minutes()*60 + td.seconds(); |
| std::tm tms, *tms_ptr; |
| tms_ptr = c_time::localtime(&t2, &tms); |
| date_type d(static_cast<unsigned short>(tms_ptr->tm_year + 1900), |
| static_cast<unsigned short>(tms_ptr->tm_mon + 1), |
| static_cast<unsigned short>(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 |