1 #ifndef DATE_TIME_LOCAL_TIMEZONE_DEFS_HPP__
2 #define DATE_TIME_LOCAL_TIMEZONE_DEFS_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
9  * $Date$
10  */
11 
12 #include "boost/date_time/dst_rules.hpp"
13 
14 namespace boost {
15   namespace date_time {
16 
17     // Configurations for common dst rules cases:
18     // See http://www.wharton.co.uk/Support/sup_dst.htm for more
19     // information on how various locales use dst rules
20 
21     //! Specification for daylight savings start rules in US
22     /*! This class is used to configure dst_calc_engine template typically
23         as follows:
24         @code
25           using namespace boost::gregorian;
26           using namespace boost::posix_time;
27           typedef us_dst_trait<date> us_dst_traits;
28           typedef boost::date_time::dst_calc_engine<date, time_duration,
29                                                     us_dst_traits>
30                                                     us_dst_calc;
31           //calculate the 2002 transition day of USA April 7 2002
32           date dst_start = us_dst_calc::local_dst_start_day(2002);
33 
34           //calculate the 2002 transition day of USA Oct 27 2002
35           date dst_end = us_dst_calc::local_dst_end_day(2002);
36 
37           //check if a local time is in dst or not -- posible answers
38           //are yes, no, invalid time label, ambiguous
39           ptime t(...some time...);
40           if (us_dst::local_is_dst(t.date(), t.time_of_day())
41               == boost::date_time::is_not_in_dst)
42           {
43 
44           }
45 
46         @endcode
47         This generates a type suitable for the calculation of dst
48         transitions for the United States.  Of course other templates
49         can be used for other locales.
50 
51     */
52 
53      template<class date_type>
54      struct us_dst_trait
55      {
56        typedef typename date_type::day_of_week_type day_of_week_type;
57        typedef typename date_type::month_type month_type;
58        typedef typename date_type::year_type year_type;
59        typedef date_time::nth_kday_of_month<date_type> start_rule_functor;
60        typedef date_time::first_kday_of_month<date_type> end_rule_functor;
61        typedef date_time::first_kday_of_month<date_type> start_rule_functor_pre2007;
62        typedef date_time::last_kday_of_month<date_type> end_rule_functor_pre2007;
start_dayboost::date_time::us_dst_trait63        static day_of_week_type start_day(year_type) {return Sunday;}
start_monthboost::date_time::us_dst_trait64        static month_type start_month(year_type y)
65        {
66          if (y < 2007) return Apr;
67          return Mar;
68        }
end_dayboost::date_time::us_dst_trait69        static day_of_week_type end_day(year_type) {return Sunday;}
end_monthboost::date_time::us_dst_trait70        static month_type end_month(year_type y)
71        {
72          if (y < 2007) return Oct;
73          return Nov;
74        }
local_dst_start_dayboost::date_time::us_dst_trait75        static date_type local_dst_start_day(year_type year)
76        {
77          if (year < 2007) {
78            start_rule_functor_pre2007 start1(start_day(year),
79                                              start_month(year));
80            return start1.get_date(year);
81          }
82          start_rule_functor start(start_rule_functor::second,
83                                   start_day(year),
84                                   start_month(year));
85          return start.get_date(year);
86 
87        }
local_dst_end_dayboost::date_time::us_dst_trait88        static date_type local_dst_end_day(year_type year)
89        {
90          if (year < 2007) {
91            end_rule_functor_pre2007 end_rule(end_day(year),
92                                              end_month(year));
93            return end_rule.get_date(year);
94          }
95          end_rule_functor end(end_day(year),
96                               end_month(year));
97          return end.get_date(year);
98        }
dst_start_offset_minutesboost::date_time::us_dst_trait99        static int dst_start_offset_minutes() { return 120;}
dst_end_offset_minutesboost::date_time::us_dst_trait100        static int dst_end_offset_minutes() { return 120; }
dst_shift_length_minutesboost::date_time::us_dst_trait101        static int dst_shift_length_minutes() { return 60; }
102      };
103 
104     //!Rules for daylight savings start in the EU (Last Sun in Mar)
105     /*!These amount to the following:
106       - Start of dst day is last Sunday in March
107       - End day of dst is last Sunday in Oct
108       - Going forward switch time is 2:00 am (offset 120 minutes)
109       - Going back switch time is 3:00 am (off set 180 minutes)
110       - Shift duration is one hour (60 minutes)
111     */
112     template<class date_type>
113     struct eu_dst_trait
114     {
115       typedef typename date_type::day_of_week_type day_of_week_type;
116       typedef typename date_type::month_type month_type;
117       typedef typename date_type::year_type year_type;
118       typedef date_time::last_kday_of_month<date_type> start_rule_functor;
119       typedef date_time::last_kday_of_month<date_type> end_rule_functor;
start_dayboost::date_time::eu_dst_trait120       static day_of_week_type start_day(year_type) {return Sunday;}
start_monthboost::date_time::eu_dst_trait121       static month_type start_month(year_type) {return Mar;}
end_dayboost::date_time::eu_dst_trait122       static day_of_week_type end_day(year_type) {return Sunday;}
end_monthboost::date_time::eu_dst_trait123       static month_type end_month(year_type) {return Oct;}
dst_start_offset_minutesboost::date_time::eu_dst_trait124       static int dst_start_offset_minutes() { return 120;}
dst_end_offset_minutesboost::date_time::eu_dst_trait125       static int dst_end_offset_minutes() { return 180; }
dst_shift_length_minutesboost::date_time::eu_dst_trait126       static int dst_shift_length_minutes() { return 60; }
local_dst_start_dayboost::date_time::eu_dst_trait127       static date_type local_dst_start_day(year_type year)
128       {
129         start_rule_functor start(start_day(year),
130                                  start_month(year));
131         return start.get_date(year);
132       }
local_dst_end_dayboost::date_time::eu_dst_trait133       static date_type local_dst_end_day(year_type year)
134       {
135         end_rule_functor end(end_day(year),
136                              end_month(year));
137         return end.get_date(year);
138       }
139     };
140 
141     //! Alternative dst traits for some parts of the United Kingdom
142     /* Several places in the UK use EU start and end rules for the
143        day, but different local conversion times (eg: forward change at 1:00
144        am local and  backward change at 2:00 am dst instead of 2:00am
145        forward and 3:00am back for the EU).
146     */
147     template<class date_type>
148     struct uk_dst_trait : public eu_dst_trait<date_type>
149     {
dst_start_offset_minutesboost::date_time::uk_dst_trait150       static int dst_start_offset_minutes() { return 60;}
dst_end_offset_minutesboost::date_time::uk_dst_trait151       static int dst_end_offset_minutes() { return 120; }
dst_shift_length_minutesboost::date_time::uk_dst_trait152       static int dst_shift_length_minutes() { return 60; }
153     };
154 
155     //Rules for Adelaide Australia
156     template<class date_type>
157     struct acst_dst_trait
158     {
159       typedef typename date_type::day_of_week_type day_of_week_type;
160       typedef typename date_type::month_type month_type;
161       typedef typename date_type::year_type year_type;
162       typedef date_time::last_kday_of_month<date_type> start_rule_functor;
163       typedef date_time::last_kday_of_month<date_type> end_rule_functor;
start_dayboost::date_time::acst_dst_trait164       static day_of_week_type start_day(year_type) {return Sunday;}
start_monthboost::date_time::acst_dst_trait165       static month_type start_month(year_type) {return Oct;}
end_dayboost::date_time::acst_dst_trait166       static day_of_week_type end_day(year_type) {return Sunday;}
end_monthboost::date_time::acst_dst_trait167       static month_type end_month(year_type) {return Mar;}
dst_start_offset_minutesboost::date_time::acst_dst_trait168       static int dst_start_offset_minutes() { return 120;}
dst_end_offset_minutesboost::date_time::acst_dst_trait169       static int dst_end_offset_minutes() { return 180; }
dst_shift_length_minutesboost::date_time::acst_dst_trait170       static int dst_shift_length_minutes() { return 60; }
local_dst_start_dayboost::date_time::acst_dst_trait171       static date_type local_dst_start_day(year_type year)
172       {
173         start_rule_functor start(start_day(year),
174                                  start_month(year));
175         return start.get_date(year);
176       }
local_dst_end_dayboost::date_time::acst_dst_trait177       static date_type local_dst_end_day(year_type year)
178       {
179         end_rule_functor end(end_day(year),
180                              end_month(year));
181         return end.get_date(year);
182       }
183     };
184 
185 
186 
187 
188 
189 
190 } } //namespace boost::date_time
191 
192 
193 #endif
194