ceph/src/boost/boost/date_time/adjust_functors.hpp

   1 #ifndef _DATE_TIME_ADJUST_FUNCTORS_HPP___
   2 #define _DATE_TIME_ADJUST_FUNCTORS_HPP___
   3
   4 /* Copyright (c) 2002,2003 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 "boost/date_time/date.hpp"
  13 #include "boost/date_time/wrapping_int.hpp"
  14
  15 namespace boost {
  16 namespace date_time {
  17
  18
  19   //! Functor to iterate a fixed number of days
  20   template<class date_type>
  21   class day_functor
  22   {
  23   public:
  24     typedef typename date_type::duration_type duration_type;
  25     day_functor(int f) : f_(f) {}
  26     duration_type get_offset(const date_type&) const
  27     {
  28       return duration_type(f_);
  29     }
  30     duration_type get_neg_offset(const date_type&) const
  31     {
  32       return duration_type(-f_);
  33     }
  34   private:
  35     int f_;
  36   };
  37
  38
  39   //! Provides calculation to find next nth month given a date
  40   /*! This adjustment function provides the logic for 'month-based'
  41    *  advancement on a ymd based calendar.  The policy it uses
  42    *  to handle the non existant end of month days is to back
  43    *  up to the last day of the month.  Also, if the starting
  44    *  date is the last day of a month, this functor will attempt
  45    *  to adjust to the end of the month.
  46
  47    */
  48   template<class date_type>
  49   class month_functor
  50   {
  51   public:
  52     typedef typename date_type::duration_type duration_type;
  53     typedef typename date_type::calendar_type cal_type;
  54     typedef typename cal_type::ymd_type ymd_type;
  55     typedef typename cal_type::day_type day_type;
  56
  57     month_functor(int f) : f_(f), origDayOfMonth_(0) {}
  58     duration_type get_offset(const date_type& d) const
  59     {
  60       ymd_type ymd(d.year_month_day());
  61       if (origDayOfMonth_ == 0) {
  62         origDayOfMonth_ = ymd.day;
  63         day_type endOfMonthDay(cal_type::end_of_month_day(ymd.year,ymd.month));
  64         if (endOfMonthDay == ymd.day) {
  65           origDayOfMonth_ = -1; //force the value to the end of month
  66         }
  67       }
  68       typedef date_time::wrapping_int2<short,1,12> wrap_int2;
  69       wrap_int2 wi(ymd.month);
  70       //calc the year wrap around, add() returns 0 or 1 if wrapped
  71       const typename ymd_type::year_type year(static_cast<typename ymd_type::year_type::value_type>(ymd.year + wi.add(f_)));
  72 //       std::cout << "trace wi: " << wi.as_int() << std::endl;
  73 //       std::cout << "trace year: " << year << std::endl;
  74       //find the last day for the new month
  75       day_type resultingEndOfMonthDay(cal_type::end_of_month_day(year, wi.as_int()));
  76       //original was the end of month -- force to last day of month
  77       if (origDayOfMonth_ == -1) {
  78         return date_type(year, wi.as_int(), resultingEndOfMonthDay) - d;
  79       }
  80       day_type dayOfMonth = origDayOfMonth_;
  81       if (dayOfMonth > resultingEndOfMonthDay) {
  82         dayOfMonth = resultingEndOfMonthDay;
  83       }
  84       return date_type(year, wi.as_int(), dayOfMonth) - d;
  85     }
  86     //! Returns a negative duration_type
  87     duration_type get_neg_offset(const date_type& d) const
  88     {
  89       ymd_type ymd(d.year_month_day());
  90       if (origDayOfMonth_ == 0) {
  91         origDayOfMonth_ = ymd.day;
  92         day_type endOfMonthDay(cal_type::end_of_month_day(ymd.year,ymd.month));
  93         if (endOfMonthDay == ymd.day) {
  94           origDayOfMonth_ = -1; //force the value to the end of month
  95         }
  96       }
  97       typedef date_time::wrapping_int2<short,1,12> wrap_int2;
  98       wrap_int2 wi(ymd.month);
  99       //calc the year wrap around, add() returns 0 or 1 if wrapped
 100       const typename ymd_type::year_type year(static_cast<typename ymd_type::year_type::value_type>(ymd.year + wi.subtract(f_)));
 101       //find the last day for the new month
 102       day_type resultingEndOfMonthDay(cal_type::end_of_month_day(year, wi.as_int()));
 103       //original was the end of month -- force to last day of month
 104       if (origDayOfMonth_ == -1) {
 105         return date_type(year, wi.as_int(), resultingEndOfMonthDay) - d;
 106       }
 107       day_type dayOfMonth = origDayOfMonth_;
 108       if (dayOfMonth > resultingEndOfMonthDay) {
 109         dayOfMonth = resultingEndOfMonthDay;
 110       }
 111       return date_type(year, wi.as_int(), dayOfMonth) - d;
 112     }
 113   private:
 114     int f_;
 115     mutable short origDayOfMonth_;
 116   };
 117
 118
 119   //! Functor to iterate a over weeks
 120   template<class date_type>
 121   class week_functor
 122   {
 123   public:
 124     typedef typename date_type::duration_type duration_type;
 125     typedef typename date_type::calendar_type calendar_type;
 126     week_functor(int f) : f_(f) {}
 127     duration_type get_offset(const date_type&) const
 128     {
 129       return duration_type(f_*static_cast<int>(calendar_type::days_in_week()));
 130     }
 131     duration_type get_neg_offset(const date_type&) const
 132     {
 133       return duration_type(-f_*static_cast<int>(calendar_type::days_in_week()));
 134     }
 135   private:
 136     int f_;
 137   };
 138
 139   //! Functor to iterate by a year adjusting for leap years
 140   template<class date_type>
 141   class year_functor
 142   {
 143   public:
 144     //typedef typename date_type::year_type year_type;
 145     typedef typename date_type::duration_type duration_type;
 146     year_functor(int f) : _mf(f * 12) {}
 147     duration_type get_offset(const date_type& d) const
 148     {
 149       return _mf.get_offset(d);
 150     }
 151     duration_type get_neg_offset(const date_type& d) const
 152     {
 153       return _mf.get_neg_offset(d);
 154     }
 155   private:
 156     month_functor<date_type> _mf;
 157   };
 158
 159
 160 } }//namespace date_time
 161
 162
 163 #endif
 164