| #ifndef LOCAL_TIME_LOCAL_DATE_TIME_HPP__ |
| #define LOCAL_TIME_LOCAL_DATE_TIME_HPP__ |
| |
| /* Copyright (c) 2003-2005 CrystalClear Software, Inc. |
| * 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: 2010-01-10 14:17:23 -0500 (Sun, 10 Jan 2010) $ |
| */ |
| |
| #include <string> |
| #include <iomanip> |
| #include <sstream> |
| #include <stdexcept> |
| #include <boost/shared_ptr.hpp> |
| #include <boost/throw_exception.hpp> |
| #include <boost/date_time/time.hpp> |
| #include <boost/date_time/posix_time/posix_time.hpp> //todo remove? |
| #include <boost/date_time/dst_rules.hpp> |
| #include <boost/date_time/time_zone_base.hpp> |
| #include <boost/date_time/special_defs.hpp> |
| #include <boost/date_time/time_resolution_traits.hpp> // absolute_value |
| |
| namespace boost { |
| namespace local_time { |
| |
| //! simple exception for reporting when STD or DST cannot be determined |
| struct ambiguous_result : public std::logic_error |
| { |
| ambiguous_result (std::string const& msg = std::string()) : |
| std::logic_error(std::string("Daylight Savings Results are ambiguous: " + msg)) {} |
| }; |
| //! simple exception for when time label given cannot exist |
| struct time_label_invalid : public std::logic_error |
| { |
| time_label_invalid (std::string const& msg = std::string()) : |
| std::logic_error(std::string("Time label given is invalid: " + msg)) {} |
| }; |
| struct dst_not_valid: public std::logic_error |
| { |
| dst_not_valid(std::string const& msg = std::string()) : |
| std::logic_error(std::string("is_dst flag does not match resulting dst for time label given: " + msg)) {} |
| }; |
| |
| //TODO: I think these should be in local_date_time_base and not |
| // necessarily brought into the namespace |
| using date_time::time_is_dst_result; |
| using date_time::is_in_dst; |
| using date_time::is_not_in_dst; |
| using date_time::ambiguous; |
| using date_time::invalid_time_label; |
| |
| //! Representation of "wall-clock" time in a particular time zone |
| /*! Representation of "wall-clock" time in a particular time zone |
| * Local_date_time_base holds a time value (date and time offset from 00:00) |
| * along with a time zone. The time value is stored as UTC and conversions |
| * to wall clock time are made as needed. This approach allows for |
| * operations between wall-clock times in different time zones, and |
| * daylight savings time considerations, to be made. Time zones are |
| * required to be in the form of a boost::shared_ptr<time_zone_base>. |
| */ |
| template<class utc_time_=posix_time::ptime, |
| class tz_type=date_time::time_zone_base<utc_time_,char> > |
| class local_date_time_base : public date_time::base_time<utc_time_, |
| boost::posix_time::posix_time_system> { |
| public: |
| typedef utc_time_ utc_time_type; |
| typedef typename utc_time_type::time_duration_type time_duration_type; |
| typedef typename utc_time_type::date_type date_type; |
| typedef typename date_type::duration_type date_duration_type; |
| typedef typename utc_time_type::time_system_type time_system_type; |
| /*! This constructor interprets the passed time as a UTC time. |
| * So, for example, if the passed timezone is UTC-5 then the |
| * time will be adjusted back 5 hours. The time zone allows for |
| * automatic calculation of whether the particular time is adjusted for |
| * daylight savings, etc. |
| * If the time zone shared pointer is null then time stays unadjusted. |
| *@param t A UTC time |
| *@param tz Timezone for to adjust the UTC time to. |
| */ |
| local_date_time_base(utc_time_type t, |
| boost::shared_ptr<tz_type> tz) : |
| date_time::base_time<utc_time_type, time_system_type>(t), |
| zone_(tz) |
| { |
| // param was already utc so nothing more to do |
| } |
| |
| /*! This constructs a local time -- the passed time information |
| * understood to be in the passed tz. The DST flag must be passed |
| * to indicate whether the time is in daylight savings or not. |
| * @throws -- time_label_invalid if the time passed does not exist in |
| * the given locale. The non-existent case occurs typically |
| * during the shift-back from daylight savings time. When |
| * the clock is shifted forward a range of times |
| * (2 am to 3 am in the US) is skipped and hence is invalid. |
| * @throws -- dst_not_valid if the DST flag is passed for a period |
| * where DST is not active. |
| */ |
| local_date_time_base(date_type d, |
| time_duration_type td, |
| boost::shared_ptr<tz_type> tz, |
| bool dst_flag) : //necessary for constr_adj() |
| date_time::base_time<utc_time_type,time_system_type>(construction_adjustment(utc_time_type(d, td), tz, dst_flag)), |
| zone_(tz) |
| { |
| if(tz != boost::shared_ptr<tz_type>() && tz->has_dst()){ |
| |
| // d & td are already local so we use them |
| time_is_dst_result result = check_dst(d, td, tz); |
| bool in_dst = (result == is_in_dst); // less processing than is_dst() |
| |
| // ambig occurs at end, invalid at start |
| if(result == invalid_time_label){ |
| // Ex: 2:15am local on trans-in day in nyc, dst_flag irrelevant |
| std::ostringstream ss; |
| ss << "time given: " << d << ' ' << td; |
| boost::throw_exception(time_label_invalid(ss.str())); |
| } |
| else if(result != ambiguous && in_dst != dst_flag){ |
| // is dst_flag accurate? |
| // Ex: false flag in NYC in June |
| std::ostringstream ss; |
| ss.setf(std::ios_base::boolalpha); |
| ss << "flag given: dst=" << dst_flag << ", dst calculated: dst=" << in_dst; |
| boost::throw_exception(dst_not_valid(ss.str())); |
| } |
| |
| // everything checks out and conversion to utc already done |
| } |
| } |
| |
| //TODO maybe not the right set...Ignore the last 2 for now... |
| enum DST_CALC_OPTIONS { EXCEPTION_ON_ERROR, NOT_DATE_TIME_ON_ERROR }; |
| //ASSUME_DST_ON_ERROR, ASSUME_NOT_DST_ON_ERROR }; |
| |
| /*! This constructs a local time -- the passed time information |
| * understood to be in the passed tz. The DST flag is calculated |
| * according to the specified rule. |
| */ |
| local_date_time_base(date_type d, |
| time_duration_type td, |
| boost::shared_ptr<tz_type> tz, |
| DST_CALC_OPTIONS calc_option) : |
| // dummy value - time_ is set in constructor code |
| date_time::base_time<utc_time_type,time_system_type>(utc_time_type(d,td)), |
| zone_(tz) |
| { |
| time_is_dst_result result = check_dst(d, td, tz); |
| if(result == ambiguous) { |
| if(calc_option == EXCEPTION_ON_ERROR){ |
| std::ostringstream ss; |
| ss << "time given: " << d << ' ' << td; |
| boost::throw_exception(ambiguous_result(ss.str())); |
| } |
| else{ // NADT on error |
| this->time_ = posix_time::posix_time_system::get_time_rep(date_type(date_time::not_a_date_time), time_duration_type(date_time::not_a_date_time)); |
| } |
| } |
| else if(result == invalid_time_label){ |
| if(calc_option == EXCEPTION_ON_ERROR){ |
| std::ostringstream ss; |
| ss << "time given: " << d << ' ' << td; |
| boost::throw_exception(time_label_invalid(ss.str())); |
| } |
| else{ // NADT on error |
| this->time_ = posix_time::posix_time_system::get_time_rep(date_type(date_time::not_a_date_time), time_duration_type(date_time::not_a_date_time)); |
| } |
| } |
| else if(result == is_in_dst){ |
| utc_time_type t = |
| construction_adjustment(utc_time_type(d, td), tz, true); |
| this->time_ = posix_time::posix_time_system::get_time_rep(t.date(), |
| t.time_of_day()); |
| } |
| else{ |
| utc_time_type t = |
| construction_adjustment(utc_time_type(d, td), tz, false); |
| this->time_ = posix_time::posix_time_system::get_time_rep(t.date(), |
| t.time_of_day()); |
| } |
| } |
| |
| |
| //! Determines if given time label is in daylight savings for given zone |
| /*! Determines if given time label is in daylight savings for given zone. |
| * Takes a date and time_duration representing a local time, along |
| * with time zone, and returns a time_is_dst_result object as result. |
| */ |
| static time_is_dst_result check_dst(date_type d, |
| time_duration_type td, |
| boost::shared_ptr<tz_type> tz) |
| { |
| if(tz != boost::shared_ptr<tz_type>() && tz->has_dst()) { |
| typedef typename date_time::dst_calculator<date_type, time_duration_type> dst_calculator; |
| return dst_calculator::local_is_dst( |
| d, td, |
| tz->dst_local_start_time(d.year()).date(), |
| tz->dst_local_start_time(d.year()).time_of_day(), |
| tz->dst_local_end_time(d.year()).date(), |
| tz->dst_local_end_time(d.year()).time_of_day(), |
| tz->dst_offset() |
| ); |
| } |
| else{ |
| return is_not_in_dst; |
| } |
| } |
| |
| //! Simple destructor, releases time zone if last referrer |
| ~local_date_time_base() {}; |
| |
| //! Copy constructor |
| local_date_time_base(const local_date_time_base& rhs) : |
| date_time::base_time<utc_time_type, time_system_type>(rhs), |
| zone_(rhs.zone_) |
| {} |
| |
| //! Special values constructor |
| explicit local_date_time_base(const boost::date_time::special_values sv, |
| boost::shared_ptr<tz_type> tz = boost::shared_ptr<tz_type>()) : |
| date_time::base_time<utc_time_type, time_system_type>(utc_time_type(sv)), |
| zone_(tz) |
| {} |
| |
| //! returns time zone associated with calling instance |
| boost::shared_ptr<tz_type> zone() const |
| { |
| return zone_; |
| } |
| //! returns false is time_zone is NULL and if time value is a special_value |
| bool is_dst() const |
| { |
| if(zone_ != boost::shared_ptr<tz_type>() && zone_->has_dst() && !this->is_special()) { |
| // check_dst takes a local time, *this is utc |
| utc_time_type lt(this->time_); |
| lt += zone_->base_utc_offset(); |
| // dst_offset only needs to be considered with ambiguous time labels |
| // make that adjustment there |
| |
| switch(check_dst(lt.date(), lt.time_of_day(), zone_)){ |
| case is_not_in_dst: |
| return false; |
| case is_in_dst: |
| return true; |
| case ambiguous: |
| if(lt + zone_->dst_offset() < zone_->dst_local_end_time(lt.date().year())) { |
| return true; |
| } |
| break; |
| case invalid_time_label: |
| if(lt >= zone_->dst_local_start_time(lt.date().year())) { |
| return true; |
| } |
| break; |
| } |
| } |
| return false; |
| } |
| //! Returns object's time value as a utc representation |
| utc_time_type utc_time() const |
| { |
| return utc_time_type(this->time_); |
| } |
| //! Returns object's time value as a local representation |
| utc_time_type local_time() const |
| { |
| if(zone_ != boost::shared_ptr<tz_type>()){ |
| utc_time_type lt = this->utc_time() + zone_->base_utc_offset(); |
| if (is_dst()) { |
| lt += zone_->dst_offset(); |
| } |
| return lt; |
| } |
| return utc_time_type(this->time_); |
| } |
| //! Returns string in the form "2003-Aug-20 05:00:00 EDT" |
| /*! Returns string in the form "2003-Aug-20 05:00:00 EDT". If |
| * time_zone is NULL the time zone abbreviation will be "UTC". The time |
| * zone abbrev will not be included if calling object is a special_value*/ |
| std::string to_string() const |
| { |
| //TODO is this a temporary function ??? |
| std::ostringstream ss; |
| if(this->is_special()){ |
| ss << utc_time(); |
| return ss.str(); |
| } |
| if(zone_ == boost::shared_ptr<tz_type>()) { |
| ss << utc_time() << " UTC"; |
| return ss.str(); |
| } |
| bool is_dst_ = is_dst(); |
| utc_time_type lt = this->utc_time() + zone_->base_utc_offset(); |
| if (is_dst_) { |
| lt += zone_->dst_offset(); |
| } |
| ss << local_time() << " "; |
| if (is_dst()) { |
| ss << zone_->dst_zone_abbrev(); |
| } |
| else { |
| ss << zone_->std_zone_abbrev(); |
| } |
| return ss.str(); |
| } |
| /*! returns a local_date_time_base in the given time zone with the |
| * optional time_duration added. */ |
| local_date_time_base local_time_in(boost::shared_ptr<tz_type> new_tz, |
| time_duration_type td=time_duration_type(0,0,0)) const |
| { |
| return local_date_time_base(utc_time_type(this->time_) + td, new_tz); |
| } |
| |
| //! Returns name of associated time zone or "Coordinated Universal Time". |
| /*! Optional bool parameter will return time zone as an offset |
| * (ie "+07:00" extended iso format). Empty string is returned for |
| * classes that do not use a time_zone */ |
| std::string zone_name(bool as_offset=false) const |
| { |
| if(zone_ == boost::shared_ptr<tz_type>()) { |
| if(as_offset) { |
| return std::string("Z"); |
| } |
| else { |
| return std::string("Coordinated Universal Time"); |
| } |
| } |
| if (is_dst()) { |
| if(as_offset) { |
| time_duration_type td = zone_->base_utc_offset(); |
| td += zone_->dst_offset(); |
| return zone_as_offset(td, ":"); |
| } |
| else { |
| return zone_->dst_zone_name(); |
| } |
| } |
| else { |
| if(as_offset) { |
| time_duration_type td = zone_->base_utc_offset(); |
| return zone_as_offset(td, ":"); |
| } |
| else { |
| return zone_->std_zone_name(); |
| } |
| } |
| } |
| //! Returns abbreviation of associated time zone or "UTC". |
| /*! Optional bool parameter will return time zone as an offset |
| * (ie "+0700" iso format). Empty string is returned for classes |
| * that do not use a time_zone */ |
| std::string zone_abbrev(bool as_offset=false) const |
| { |
| if(zone_ == boost::shared_ptr<tz_type>()) { |
| if(as_offset) { |
| return std::string("Z"); |
| } |
| else { |
| return std::string("UTC"); |
| } |
| } |
| if (is_dst()) { |
| if(as_offset) { |
| time_duration_type td = zone_->base_utc_offset(); |
| td += zone_->dst_offset(); |
| return zone_as_offset(td, ""); |
| } |
| else { |
| return zone_->dst_zone_abbrev(); |
| } |
| } |
| else { |
| if(as_offset) { |
| time_duration_type td = zone_->base_utc_offset(); |
| return zone_as_offset(td, ""); |
| } |
| else { |
| return zone_->std_zone_abbrev(); |
| } |
| } |
| } |
| |
| //! returns a posix_time_zone string for the associated time_zone. If no time_zone, "UTC+00" is returned. |
| std::string zone_as_posix_string() const |
| { |
| if(zone_ == shared_ptr<tz_type>()) { |
| return std::string("UTC+00"); |
| } |
| return zone_->to_posix_string(); |
| } |
| |
| //! Equality comparison operator |
| /*bool operator==(const date_time::base_time<boost::posix_time::ptime,boost::posix_time::posix_time_system>& rhs) const |
| { // fails due to rhs.time_ being protected |
| return date_time::base_time<boost::posix_time::ptime,boost::posix_time::posix_time_system>::operator==(rhs); |
| //return this->time_ == rhs.time_; |
| }*/ |
| //! Equality comparison operator |
| bool operator==(const local_date_time_base& rhs) const |
| { |
| return time_system_type::is_equal(this->time_, rhs.time_); |
| } |
| //! Non-Equality comparison operator |
| bool operator!=(const local_date_time_base& rhs) const |
| { |
| return !(*this == rhs); |
| } |
| //! Less than comparison operator |
| bool operator<(const local_date_time_base& rhs) const |
| { |
| return time_system_type::is_less(this->time_, rhs.time_); |
| } |
| //! Less than or equal to comparison operator |
| bool operator<=(const local_date_time_base& rhs) const |
| { |
| return (*this < rhs || *this == rhs); |
| } |
| //! Greater than comparison operator |
| bool operator>(const local_date_time_base& rhs) const |
| { |
| return !(*this <= rhs); |
| } |
| //! Greater than or equal to comparison operator |
| bool operator>=(const local_date_time_base& rhs) const |
| { |
| return (*this > rhs || *this == rhs); |
| } |
| |
| //! Local_date_time + date_duration |
| local_date_time_base operator+(const date_duration_type& dd) const |
| { |
| return local_date_time_base(time_system_type::add_days(this->time_,dd), zone_); |
| } |
| //! Local_date_time += date_duration |
| local_date_time_base operator+=(const date_duration_type& dd) |
| { |
| this->time_ = time_system_type::add_days(this->time_,dd); |
| return *this; |
| } |
| //! Local_date_time - date_duration |
| local_date_time_base operator-(const date_duration_type& dd) const |
| { |
| return local_date_time_base(time_system_type::subtract_days(this->time_,dd), zone_); |
| } |
| //! Local_date_time -= date_duration |
| local_date_time_base operator-=(const date_duration_type& dd) |
| { |
| this->time_ = time_system_type::subtract_days(this->time_,dd); |
| return *this; |
| } |
| //! Local_date_time + time_duration |
| local_date_time_base operator+(const time_duration_type& td) const |
| { |
| return local_date_time_base(time_system_type::add_time_duration(this->time_,td), zone_); |
| } |
| //! Local_date_time += time_duration |
| local_date_time_base operator+=(const time_duration_type& td) |
| { |
| this->time_ = time_system_type::add_time_duration(this->time_,td); |
| return *this; |
| } |
| //! Local_date_time - time_duration |
| local_date_time_base operator-(const time_duration_type& td) const |
| { |
| return local_date_time_base(time_system_type::subtract_time_duration(this->time_,td), zone_); |
| } |
| //! Local_date_time -= time_duration |
| local_date_time_base operator-=(const time_duration_type& td) |
| { |
| this->time_ = time_system_type::subtract_time_duration(this->time_,td); |
| return *this; |
| } |
| //! local_date_time -= local_date_time --> time_duration_type |
| time_duration_type operator-(const local_date_time_base& rhs) const |
| { |
| return utc_time_type(this->time_) - utc_time_type(rhs.time_); |
| } |
| private: |
| boost::shared_ptr<tz_type> zone_; |
| //bool is_dst_; |
| |
| /*! Adjust the passed in time to UTC? |
| */ |
| utc_time_type construction_adjustment(utc_time_type t, |
| boost::shared_ptr<tz_type> z, |
| bool dst_flag) |
| { |
| if(z != boost::shared_ptr<tz_type>()) { |
| if(dst_flag && z->has_dst()) { |
| t -= z->dst_offset(); |
| } // else no adjust |
| t -= z->base_utc_offset(); |
| } |
| return t; |
| } |
| |
| /*! Simple formatting code -- todo remove this? |
| */ |
| std::string zone_as_offset(const time_duration_type& td, |
| const std::string& separator) const |
| { |
| std::ostringstream ss; |
| if(td.is_negative()) { |
| // a negative duration is represented as "-[h]h:mm" |
| // we require two digits for the hour. A positive duration |
| // with the %H flag will always give two digits |
| ss << "-"; |
| } |
| else { |
| ss << "+"; |
| } |
| ss << std::setw(2) << std::setfill('0') |
| << date_time::absolute_value(td.hours()) |
| << separator |
| << std::setw(2) << std::setfill('0') |
| << date_time::absolute_value(td.minutes()); |
| return ss.str(); |
| } |
| }; |
| |
| //!Use the default parameters to define local_date_time |
| typedef local_date_time_base<> local_date_time; |
| |
| } } |
| |
| |
| #endif |