FM / date

/usr/include/boost/date_time

Name	Size	Mode	Actions
gregorian/	-	0755	rm
local_time/	-	0755	rm
posix_time/	-	0755	rm
adjust_functors.hpp	5467	0644	edit dl rm
compiler_config.hpp	5640	0644	edit dl rm
constrained_value.hpp	4224	0644	edit dl rm
c_local_time_adjustor.hpp	2631	0644	edit dl rm
c_time.hpp	4496	0644	edit dl rm
date.hpp	7357	0644	edit dl rm
date_clock_device.hpp	2299	0644	edit dl rm
date_defs.hpp	701	0644	edit dl rm
date_duration.hpp	4669	0644	edit dl rm
date_duration_types.hpp	9186	0644	edit dl rm
date_facet.hpp	29314	0644	edit dl rm
date_formatting.hpp	4208	0644	edit dl rm
date_formatting_limited.hpp	3461	0644	edit dl rm
date_formatting_locales.hpp	6748	0644	edit dl rm
date_format_simple.hpp	3128	0644	edit dl rm
date_generators.hpp	16508	0644	edit dl rm
date_generator_formatter.hpp	11715	0644	edit dl rm
date_generator_parser.hpp	13064	0644	edit dl rm
date_iterator.hpp	3305	0644	edit dl rm
date_names_put.hpp	10754	0644	edit dl rm
date_parsing.hpp	14146	0644	edit dl rm
dst_rules.hpp	15401	0644	edit dl rm
dst_transition_generators.hpp	2293	0644	edit dl rm
filetime_functions.hpp	3163	0644	edit dl rm
find_match.hpp	1355	0644	edit dl rm
format_date_parser.hpp	23909	0644	edit dl rm
gregorian_calendar.hpp	2714	0644	edit dl rm
gregorian_calendar.ipp	7947	0644	edit dl rm
int_adapter.hpp	14463	0644	edit dl rm
iso_format.hpp	5640	0644	edit dl rm
locale_config.hpp	1206	0644	edit dl rm
local_timezone_defs.hpp	7618	0644	edit dl rm
local_time_adjustor.hpp	8578	0644	edit dl rm
microsec_time_clock.hpp	6257	0644	edit dl rm
parse_format_base.hpp	961	0644	edit dl rm
period.hpp	11936	0644	edit dl rm
period_formatter.hpp	7237	0644	edit dl rm
period_parser.hpp	7932	0644	edit dl rm
special_defs.hpp	633	0644	edit dl rm
special_values_formatter.hpp	3657	0644	edit dl rm
special_values_parser.hpp	6161	0644	edit dl rm
strings_from_facet.hpp	4505	0644	edit dl rm
string_convert.hpp	1002	0644	edit dl rm
string_parse_tree.hpp	8405	0644	edit dl rm
time.hpp	6788	0644	edit dl rm
time_clock.hpp	2245	0644	edit dl rm
time_defs.hpp	942	0644	edit dl rm
time_duration.hpp	10569	0644	edit dl rm
time_facet.hpp	58988	0644	edit dl rm
time_formatting_streams.hpp	3752	0644	edit dl rm
time_iterator.hpp	1438	0644	edit dl rm
time_parsing.hpp	11846	0644	edit dl rm
time_resolution_traits.hpp	6760	0644	edit dl rm
time_system_counted.hpp	9051	0644	edit dl rm
time_system_split.hpp	8077	0644	edit dl rm
time_zone_base.hpp	3711	0644	edit dl rm
time_zone_names.hpp	3103	0644	edit dl rm
tz_db_base.hpp	15915	0644	edit dl rm
wrapping_int.hpp	5824	0644	edit dl rm
year_month_day.hpp	1375	0644	edit dl rm

Edit: /usr/include/boost/date_time/local_time_adjustor.hpp (8578B)

#ifndef DATE_TIME_LOCAL_TIME_ADJUSTOR_HPP__
#define DATE_TIME_LOCAL_TIME_ADJUSTOR_HPP__

/* Copyright (c) 2002,2003 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 
 * $Date$
 */

/*! @file local_time_adjustor.hpp
  Time adjustment calculations for local times
*/

#include <stdexcept>
#include <boost/throw_exception.hpp>
#include <boost/date_time/compiler_config.hpp>
#include <boost/date_time/date_generators.hpp>
#include <boost/date_time/dst_rules.hpp>
#include <boost/date_time/time_defs.hpp> // boost::date_time::dst_flags
#include <boost/date_time/special_defs.hpp> // not_a_date_time

namespace boost {
  namespace date_time {

//! Provides a base offset adjustment from utc
    template<class time_duration_type, 
             short hours, unsigned short minutes = 0>
    class utc_adjustment 
    {
    public:
      static time_duration_type local_to_utc_base_offset()
      {
        time_duration_type td(hours,minutes,0);
        return td.invert_sign();
      }
      static time_duration_type utc_to_local_base_offset()
      {
        return time_duration_type(hours,minutes,0);
      }
    };

//! Allow sliding utc adjustment with fixed dst rules
    template<class time_type, class dst_rules>
    class dynamic_local_time_adjustor : public dst_rules
    {
    public:
      typedef typename time_type::time_duration_type time_duration_type;
      typedef typename time_type::date_type date_type;

dynamic_local_time_adjustor(time_duration_type utc_offset) :
        utc_offset_(utc_offset)
      {}
      
      //! Presumes local time
      time_duration_type utc_offset(bool is_dst) 
      { 
        if (is_dst) {
          return utc_offset_ + this->dst_offset();
        }
        else {
          return utc_offset_;
        }

}
    private:
      time_duration_type utc_offset_;

};

//! Embed the rules for local time adjustments at compile time
    template<class time_type, class dst_rules, class utc_offset_rules>
    class static_local_time_adjustor: public dst_rules, public utc_offset_rules
    {
    public:
      typedef typename time_type::time_duration_type time_duration_type;
      typedef typename time_type::date_type date_type;

//! Calculates the offset from a utc time to local based on dst and utc offset
      /*! @param t UTC time to calculate offset to local time
       *  This adjustment depends on the following observations about the
       *  workings of the DST boundary offset.  Since UTC time labels are
       *  monotonically increasing we can determine if a given local time
       *  is in DST or not and therefore adjust the offset appropriately.
       * 
       *  The logic is as follows.  Starting with UTC time use the offset to
       *  create a label for an non-dst adjusted local time.  Then call
       *  dst_rules::local_is_dst with the non adjust local time.  The
       *  results of this function will either unabiguously decide that
       *  the initial local time is in dst or return an illegal or
       *  ambiguous result.  An illegal result only occurs at the end
       *  of dst (where labels are skipped) and indicates that dst has
       *  ended.  An ambiguous result means that we need to recheck by
       *  making a dst adjustment and then rechecking.  If the dst offset
       *  is added to the utc time and the recheck proves non-ambiguous
       *  then we are past the boundary.  If it is still ambiguous then
       *  we are ahead of the boundary and dst is still in effect.
       *
       *  TODO -- check if all dst offsets are positive.  If not then
       *  the algorithm needs to check for this and reverse the 
       *  illegal/ambiguous logic.
       */
      static time_duration_type utc_to_local_offset(const time_type& t)
      {
        //get initial local time guess by applying utc offset
        time_type initial = t + utc_offset_rules::utc_to_local_base_offset();
        time_is_dst_result dst_flag = 
          dst_rules::local_is_dst(initial.date(), initial.time_of_day());
        switch(dst_flag) {
        case is_in_dst:        return utc_offset_rules::utc_to_local_base_offset() + dst_rules::dst_offset();
        case is_not_in_dst:    return utc_offset_rules::utc_to_local_base_offset();
        case invalid_time_label:return utc_offset_rules::utc_to_local_base_offset() + dst_rules::dst_offset();
        case ambiguous: {
          time_type retry = initial + dst_rules::dst_offset();
          dst_flag = dst_rules::local_is_dst(retry.date(), retry.time_of_day());
          //if still ambibuous then the utc time still translates to a dst time
          if (dst_flag == ambiguous) {
            return utc_offset_rules::utc_to_local_base_offset() + dst_rules::dst_offset();
          }
          // we are past the dst boundary
          else {
            return utc_offset_rules::utc_to_local_base_offset();
          }
        }
        }//case
        //TODO  better exception type
        boost::throw_exception(std::out_of_range("Unreachable case"));
        BOOST_DATE_TIME_UNREACHABLE_EXPRESSION(return time_duration_type(not_a_date_time)); // should never reach
      }

//! Get the offset to UTC given a local time
      static time_duration_type local_to_utc_offset(const time_type& t, 
                                                    date_time::dst_flags dst=date_time::calculate) 
      {
        switch (dst) {
        case is_dst:
          return utc_offset_rules::local_to_utc_base_offset() - dst_rules::dst_offset();
        case not_dst:
          return utc_offset_rules::local_to_utc_base_offset();
        case calculate:
          time_is_dst_result res = 
            dst_rules::local_is_dst(t.date(), t.time_of_day());
          switch(res) {
          case is_in_dst:      return utc_offset_rules::local_to_utc_base_offset() - dst_rules::dst_offset();
          case is_not_in_dst:      return utc_offset_rules::local_to_utc_base_offset();
          case ambiguous:          return utc_offset_rules::local_to_utc_base_offset();
          case invalid_time_label: break;
          }
        }
        boost::throw_exception(std::out_of_range("Time label invalid"));
        BOOST_DATE_TIME_UNREACHABLE_EXPRESSION(return time_duration_type(not_a_date_time)); // should never reach
      }

private:

};

void dummy_to_prevent_msvc6_ice(); //why ask why?

//! Template that simplifies the creation of local time calculator 
    /*! Use this template to create the timezone to utc convertors as required.
     * 
     *  This class will also work for other regions that don't use dst and
     *  have a utc offset which is an integral number of hours.
     *
     *  <b>Template Parameters</b>
     *  -time_type  -- Time class to use
     *  -utc_offset -- Number hours local time is adjust from utc
     *  -use_dst -- true (default) if region uses dst, false otherwise
     *  For example:
     *  @code
     *  //eastern timezone is utc-5
     typedef date_time::local_adjustor<ptime, -5, us_dst> us_eastern;
     typedef date_time::local_adjustor<ptime, -6, us_dst> us_central;
     typedef date_time::local_adjustor<ptime, -7, us_dst> us_mountain;
     typedef date_time::local_adjustor<ptime, -8, us_dst> us_pacific;
     typedef date_time::local_adjustor<ptime, -7, no_dst> us_arizona;
     @endcode
      
    */
    template<class time_type, short utc_offset, class dst_rule>
    class local_adjustor
    {
    public:
      typedef typename time_type::time_duration_type time_duration_type;
      typedef typename time_type::date_type date_type;
      typedef static_local_time_adjustor<time_type, 
                                         dst_rule,
                                         utc_adjustment<time_duration_type, 
                                                        utc_offset> > dst_adjustor;
      //! Convert a utc time to local time
      static time_type utc_to_local(const time_type& t)
      {
        time_duration_type td = dst_adjustor::utc_to_local_offset(t);
        return t + td;
      }
      //! Convert a local time to utc
      static time_type local_to_utc(const time_type& t, 
                                    date_time::dst_flags dst=date_time::calculate)
      {
        time_duration_type td = dst_adjustor::local_to_utc_offset(t, dst);
        return t + td;
      }
    };

} } //namespace date_time

#endif

cmd: