ceph/src/boost/libs/date_time/include/boost/date_time/gregorian/conversion.hpp

   1 #ifndef _GREGORIAN__CONVERSION_HPP___
   2 #define _GREGORIAN__CONVERSION_HPP___
   3
   4 /* Copyright (c) 2004-2005 CrystalClear Software, Inc.
   5  * Use, modification and distribution is subject to the
   6  * Boost Software License, Version 1.0. (See accompanying
   7  * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
   8  * Author: Jeff Garland, Bart Garst
   9  * $Date$
  10  */
  11
  12 #include <cstring>
  13 #include <string>
  14 #include <stdexcept>
  15 #include <boost/throw_exception.hpp>
  16 #include <boost/date_time/c_time.hpp>
  17 #include <boost/date_time/special_defs.hpp>
  18 #include <boost/date_time/gregorian/gregorian_types.hpp>
  19
  20 namespace boost {
  21
  22 namespace gregorian {
  23
  24   //! Converts a date to a tm struct. Throws out_of_range exception if date is a special value
  25   inline
  26   std::tm to_tm(const date& d)
  27   {
  28     if (d.is_special())
  29     {
  30         std::string s = "tm unable to handle ";
  31         switch (d.as_special())
  32         {
  33         case date_time::not_a_date_time:
  34             s += "not-a-date-time value"; break;
  35         case date_time::neg_infin:
  36             s += "-infinity date value"; break;
  37         case date_time::pos_infin:
  38             s += "+infinity date value"; break;
  39         default:
  40             s += "a special date value"; break;
  41         }
  42         boost::throw_exception(std::out_of_range(s));
  43     }
  44
  45     std::tm datetm;
  46     std::memset(&datetm, 0, sizeof(datetm));
  47     boost::gregorian::date::ymd_type ymd = d.year_month_day();
  48     datetm.tm_year = ymd.year - 1900;
  49     datetm.tm_mon = ymd.month - 1;
  50     datetm.tm_mday = ymd.day;
  51     datetm.tm_wday = d.day_of_week();
  52     datetm.tm_yday = d.day_of_year() - 1;
  53     datetm.tm_isdst = -1; // negative because not enough info to set tm_isdst
  54     return datetm;
  55   }
  56
  57   //! Converts a tm structure into a date dropping the any time values.
  58   inline
  59   date date_from_tm(const std::tm& datetm)
  60   {
  61     return date(static_cast<unsigned short>(datetm.tm_year+1900),
  62                 static_cast<unsigned short>(datetm.tm_mon+1),
  63                 static_cast<unsigned short>(datetm.tm_mday));
  64   }
  65
  66 } } //namespace boost::gregorian
  67
  68 #endif