summaryrefslogtreecommitdiff
path: root/boost/date_time/local_time/local_date_time.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'boost/date_time/local_time/local_date_time.hpp')
-rw-r--r--boost/date_time/local_time/local_date_time.hpp528
1 files changed, 528 insertions, 0 deletions
diff --git a/boost/date_time/local_time/local_date_time.hpp b/boost/date_time/local_time/local_date_time.hpp
new file mode 100644
index 0000000000..9c9f62340f
--- /dev/null
+++ b/boost/date_time/local_time/local_date_time.hpp
@@ -0,0 +1,528 @@
+#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