#ifndef _DATE_TIME_POSIX_TIME_ZONE__
#define _DATE_TIME_POSIX_TIME_ZONE__
/* 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: 2010-06-10 13:24:38 -0400 (Thu, 10 Jun 2010) $
*/
#include <string>
#include <sstream>
#include <stdexcept>
#include <boost/tokenizer.hpp>
#include <boost/throw_exception.hpp>
#include <boost/date_time/gregorian/gregorian.hpp>
#include <boost/date_time/time_zone_names.hpp>
#include <boost/date_time/time_zone_base.hpp>
#include <boost/date_time/local_time/dst_transition_day_rules.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>
#include <boost/date_time/string_convert.hpp>
#include <boost/date_time/time_parsing.hpp>
namespace boost{
namespace local_time{
//! simple exception for UTC and Daylight savings start/end offsets
struct bad_offset : public std::out_of_range
{
bad_offset(std::string const& msg = std::string()) :
std::out_of_range(std::string("Offset out of range: " + msg)) {}
};
//! simple exception for UTC daylight savings adjustment
struct bad_adjustment : public std::out_of_range
{
bad_adjustment(std::string const& msg = std::string()) :
std::out_of_range(std::string("Adjustment out of range: " + msg)) {}
};
typedef boost::date_time::dst_adjustment_offsets<boost::posix_time::time_duration> dst_adjustment_offsets;
//! A time zone class constructed from a POSIX time zone string
/*! A POSIX time zone string takes the form of:<br>
* "std offset dst [offset],start[/time],end[/time]" (w/no spaces)
* 'std' specifies the abbrev of the time zone.<br>
* 'offset' is the offset from UTC.<br>
* 'dst' specifies the abbrev of the time zone during daylight savings time.<br>
* The second offset is how many hours changed during DST. Default=1<br>
* 'start' and'end' are the dates when DST goes into (and out of) effect.<br>
* 'offset' takes the form of: [+|-]hh[:mm[:ss]] {h=0-23, m/s=0-59}<br>
* 'time' and 'offset' take the same form. Time defaults=02:00:00<br>
* 'start' and 'end' can be one of three forms:<br>
* Mm.w.d {month=1-12, week=1-5 (5 is always last), day=0-6}<br>
* Jn {n=1-365 Feb29 is never counted}<br>
* n {n=0-365 Feb29 is counted in leap years}<br>
* Example "PST-5PDT01:00:00,M4.1.0/02:00:00,M10.1.0/02:00:00"
* <br>
* Exceptions will be thrown under these conditions:<br>
* An invalid date spec (see date class)<br>
* A boost::local_time::bad_offset exception will be thrown for:<br>
* A DST start or end offset that is negative or more than 24 hours<br>
* A UTC zone that is greater than +14 or less than -12 hours<br>
* A boost::local_time::bad_adjustment exception will be thrown for:<br>
* A DST adjustment that is 24 hours or more (positive or negative)<br>
*
* Note that UTC zone offsets can be greater than +12:
* http://www.worldtimezone.com/utc/utc+1200.html
*/
template<class CharT>
class posix_time_zone_base : public date_time::time_zone_base<posix_time::ptime,CharT> {
public:
typedef boost::posix_time::time_duration time_duration_type;
typedef date_time::time_zone_names_base<CharT> time_zone_names;
typedef date_time::time_zone_base<posix_time::ptime,CharT> base_type;
typedef typename base_type::string_type string_type;
typedef CharT char_type;
typedef typename base_type::stringstream_type stringstream_type;
typedef boost::char_separator<char_type, std::char_traits<char_type> > char_separator_type;
typedef boost::tokenizer<char_separator_type,
typename string_type::const_iterator,
string_type> tokenizer_type;
typedef typename tokenizer_type::iterator tokenizer_iterator_type;
//! Construct from a POSIX time zone string
posix_time_zone_base(const string_type& s) :
//zone_names_("std_name","std_abbrev","no-dst","no-dst"),
zone_names_(),
has_dst_(false),
base_utc_offset_(posix_time::hours(0)),
dst_offsets_(posix_time::hours(0),posix_time::hours(0),posix_time::hours(0)),
dst_calc_rules_()
{
#ifdef __HP_aCC
// Work around bug in aC++ compiler: see QXCR1000880488 in the
// HP bug tracking system
const char_type sep_chars[2] = {',',0};
#else
const char_type sep_chars[2] = {','};
#endif
char_separator_type sep(sep_chars);
tokenizer_type tokens(s, sep);
tokenizer_iterator_type it = tokens.begin(), end = tokens.end();
if (it == end)
BOOST_THROW_EXCEPTION(std::invalid_argument("Could not parse time zone name"));
calc_zone(*it++);
if(has_dst_)
{
if (it == end)
BOOST_THROW_EXCEPTION(std::invalid_argument("Could not parse DST begin time"));
string_type dst_begin = *it++;
if (it == end)
BOOST_THROW_EXCEPTION(std::invalid_argument("Could not parse DST end time"));
string_type dst_end = *it;
calc_rules(dst_begin, dst_end);
}
}
virtual ~posix_time_zone_base() {};
//!String for the zone when not in daylight savings (eg: EST)
virtual string_type std_zone_abbrev()const
{
return zone_names_.std_zone_abbrev();
}
//!String for the timezone when in daylight savings (eg: EDT)
/*! For those time zones that have no DST, an empty string is used */
virtual string_type dst_zone_abbrev() const
{
return zone_names_.dst_zone_abbrev();
}
//!String for the zone when not in daylight savings (eg: Eastern Standard Time)
/*! The full STD name is not extracted from the posix time zone string.
* Therefore, the STD abbreviation is used in it's place */
virtual string_type std_zone_name()const
{
return zone_names_.std_zone_name();
}
//!String for the timezone when in daylight savings (eg: Eastern Daylight Time)
/*! The full DST name is not extracted from the posix time zone string.
* Therefore, the STD abbreviation is used in it's place. For time zones
* that have no DST, an empty string is used */
virtual string_type dst_zone_name()const
{
return zone_names_.dst_zone_name();
}
//! True if zone uses daylight savings adjustments otherwise false
virtual bool has_dst()const
{
return has_dst_;
}
//! Local time that DST starts -- NADT if has_dst is false
virtual posix_time::ptime dst_local_start_time(gregorian::greg_year y)const
{
gregorian::date d(gregorian::not_a_date_time);
if(has_dst_)
{
d = dst_calc_rules_->start_day(y);
}
return posix_time::ptime(d, dst_offsets_.dst_start_offset_);
}
//! Local time that DST ends -- NADT if has_dst is false
virtual posix_time::ptime dst_local_end_time(gregorian::greg_year y)const
{
gregorian::date d(gregorian::not_a_date_time);
if(has_dst_)
{
d = dst_calc_rules_->end_day(y);
}
return posix_time::ptime(d, dst_offsets_.dst_end_offset_);
}
//! Base offset from UTC for zone (eg: -07:30:00)
virtual time_duration_type base_utc_offset()const
{
return base_utc_offset_;
}
//! Adjustment forward or back made while DST is in effect
virtual time_duration_type dst_offset()const
{
return dst_offsets_.dst_adjust_;
}
//! Returns a POSIX time_zone string for this object
virtual string_type to_posix_string() const
{
// std offset dst [offset],start[/time],end[/time] - w/o spaces
stringstream_type ss;
ss.fill('0');
boost::shared_ptr<dst_calc_rule> no_rules;
// std
ss << std_zone_abbrev();
// offset
if(base_utc_offset().is_negative()) {
// inverting the sign guarantees we get two digits
ss << '-' << std::setw(2) << base_utc_offset().invert_sign().hours();
}
else {
ss << '+' << std::setw(2) << base_utc_offset().hours();
}
if(base_utc_offset().minutes() != 0 || base_utc_offset().seconds() != 0) {
ss << ':' << std::setw(2) << base_utc_offset().minutes();
if(base_utc_offset().seconds() != 0) {
ss << ':' << std::setw(2) << base_utc_offset().seconds();
}
}
if(dst_calc_rules_ != no_rules) {
// dst
ss << dst_zone_abbrev();
// dst offset
if(dst_offset().is_negative()) {
// inverting the sign guarantees we get two digits
ss << '-' << std::setw(2) << dst_offset().invert_sign().hours();
}
else {
ss << '+' << std::setw(2) << dst_offset().hours();
}
if(dst_offset().minutes() != 0 || dst_offset().seconds() != 0) {
ss << ':' << std::setw(2) << dst_offset().minutes();
if(dst_offset().seconds() != 0) {
ss << ':' << std::setw(2) << dst_offset().seconds();
}
}
// start/time
ss << ',' << date_time::convert_string_type<char, char_type>(dst_calc_rules_->start_rule_as_string()) << '/'
<< std::setw(2) << dst_offsets_.dst_start_offset_.hours() << ':'
<< std::setw(2) << dst_offsets_.dst_start_offset_.minutes();
if(dst_offsets_.dst_start_offset_.seconds() != 0) {
ss << ':' << std::setw(2) << dst_offsets_.dst_start_offset_.seconds();
}
// end/time
ss << ',' << date_time::convert_string_type<char, char_type>(dst_calc_rules_->end_rule_as_string()) << '/'
<< std::setw(2) << dst_offsets_.dst_end_offset_.hours() << ':'
<< std::setw(2) << dst_offsets_.dst_end_offset_.minutes();
if(dst_offsets_.dst_end_offset_.seconds() != 0) {
ss << ':' << std::setw(2) << dst_offsets_.dst_end_offset_.seconds();
}
}
return ss.str();
}
private:
time_zone_names zone_names_;
bool has_dst_;
time_duration_type base_utc_offset_;
dst_adjustment_offsets dst_offsets_;
boost::shared_ptr<dst_calc_rule> dst_calc_rules_;
/*! Extract time zone abbreviations for STD & DST as well
* as the offsets for the time shift that occurs and how
* much of a shift. At this time full time zone names are
* NOT extracted so the abbreviations are used in their place */
void calc_zone(const string_type& obj){
const char_type empty_string[2] = {'\0'};
stringstream_type ss(empty_string);
typename string_type::const_pointer sit = obj.c_str(), obj_end = sit + obj.size();
string_type l_std_zone_abbrev, l_dst_zone_abbrev;
// get 'std' name/abbrev
while(std::isalpha(*sit)){
ss << *sit++;
}
l_std_zone_abbrev = ss.str();
ss.str(empty_string);
// get UTC offset
if(sit != obj_end){
// get duration
while(sit != obj_end && !std::isalpha(*sit)){
ss << *sit++;
}
base_utc_offset_ = date_time::str_from_delimited_time_duration<time_duration_type,char_type>(ss.str());
ss.str(empty_string);
// base offset must be within range of -12 hours to +14 hours
if(base_utc_offset_ < time_duration_type(-12,0,0) ||
base_utc_offset_ > time_duration_type(14,0,0))
{
boost::throw_exception(bad_offset(posix_time::to_simple_string(base_utc_offset_)));
}
}
// get DST data if given
if(sit != obj_end){
has_dst_ = true;
// get 'dst' name/abbrev
while(sit != obj_end && std::isalpha(*sit)){
ss << *sit++;
}
l_dst_zone_abbrev = ss.str();
ss.str(empty_string);
// get DST offset if given
if(sit != obj_end){
// get duration
while(sit != obj_end && !std::isalpha(*sit)){
ss << *sit++;
}
dst_offsets_.dst_adjust_ = date_time::str_from_delimited_time_duration<time_duration_type,char_type>(ss.str());
ss.str(empty_string);
}
else{ // default DST offset
dst_offsets_.dst_adjust_ = posix_time::hours(1);
}
// adjustment must be within +|- 1 day
if(dst_offsets_.dst_adjust_ <= time_duration_type(-24,0,0) ||
dst_offsets_.dst_adjust_ >= time_duration_type(24,0,0))
{
boost::throw_exception(bad_adjustment(posix_time::to_simple_string(dst_offsets_.dst_adjust_)));
}
}
// full names not extracted so abbrevs used in their place
zone_names_ = time_zone_names(l_std_zone_abbrev, l_std_zone_abbrev, l_dst_zone_abbrev, l_dst_zone_abbrev);
}
void calc_rules(const string_type& start, const string_type& end){
#ifdef __HP_aCC
// Work around bug in aC++ compiler: see QXCR1000880488 in the
// HP bug tracking system
const char_type sep_chars[2] = {'/',0};
#else
const char_type sep_chars[2] = {'/'};
#endif
char_separator_type sep(sep_chars);
tokenizer_type st_tok(start, sep);
tokenizer_type et_tok(end, sep);
tokenizer_iterator_type sit = st_tok.begin();
tokenizer_iterator_type eit = et_tok.begin();
// generate date spec
char_type x = string_type(*sit).at(0);
if(x == 'M'){
M_func(*sit, *eit);
}
else if(x == 'J'){
julian_no_leap(*sit, *eit);
}
else{
julian_day(*sit, *eit);
}
++sit;
++eit;
// generate durations
// starting offset
if(sit != st_tok.end()){
dst_offsets_.dst_start_offset_ = date_time::str_from_delimited_time_duration<time_duration_type,char_type>(*sit);
}
else{
// default
dst_offsets_.dst_start_offset_ = posix_time::hours(2);
}
// start/end offsets must fall on given date
if(dst_offsets_.dst_start_offset_ < time_duration_type(0,0,0) ||
dst_offsets_.dst_start_offset_ >= time_duration_type(24,0,0))
{
boost::throw_exception(bad_offset(posix_time::to_simple_string(dst_offsets_.dst_start_offset_)));
}
// ending offset
if(eit != et_tok.end()){
dst_offsets_.dst_end_offset_ = date_time::str_from_delimited_time_duration<time_duration_type,char_type>(*eit);
}
else{
// default
dst_offsets_.dst_end_offset_ = posix_time::hours(2);
}
// start/end offsets must fall on given date
if(dst_offsets_.dst_end_offset_ < time_duration_type(0,0,0) ||
dst_offsets_.dst_end_offset_ >= time_duration_type(24,0,0))
{
boost::throw_exception(bad_offset(posix_time::to_simple_string(dst_offsets_.dst_end_offset_)));
}
}
/* Parses out a start/end date spec from a posix time zone string.
* Date specs come in three possible formats, this function handles
* the 'M' spec. Ex "M2.2.4" => 2nd month, 2nd week, 4th day .
*/
void M_func(const string_type& s, const string_type& e){
typedef gregorian::nth_kday_of_month nkday;
unsigned short sm=0,sw=0,sd=0,em=0,ew=0,ed=0; // start/end month,week,day
#ifdef __HP_aCC
// Work around bug in aC++ compiler: see QXCR1000880488 in the
// HP bug tracking system
const char_type sep_chars[3] = {'M','.',0};
#else
const char_type sep_chars[3] = {'M','.'};
#endif
char_separator_type sep(sep_chars);
tokenizer_type stok(s, sep), etok(e, sep);
tokenizer_iterator_type it = stok.begin();
sm = lexical_cast<unsigned short>(*it++);
sw = lexical_cast<unsigned short>(*it++);
sd = lexical_cast<unsigned short>(*it);
it = etok.begin();
em = lexical_cast<unsigned short>(*it++);
ew = lexical_cast<unsigned short>(*it++);
ed = lexical_cast<unsigned short>(*it);
dst_calc_rules_ = shared_ptr<dst_calc_rule>(
new nth_kday_dst_rule(
nth_last_dst_rule::start_rule(
static_cast<nkday::week_num>(sw),sd,sm),
nth_last_dst_rule::start_rule(
static_cast<nkday::week_num>(ew),ed,em)
)
);
}
//! Julian day. Feb29 is never counted, even in leap years
// expects range of 1-365
void julian_no_leap(const string_type& s, const string_type& e){
typedef gregorian::gregorian_calendar calendar;
const unsigned short year = 2001; // Non-leap year
unsigned short sm=1;
int sd=0;
sd = lexical_cast<int>(s.substr(1)); // skip 'J'
while(sd >= calendar::end_of_month_day(year,sm)){
sd -= calendar::end_of_month_day(year,sm++);
}
unsigned short em=1;
int ed=0;
ed = lexical_cast<int>(e.substr(1)); // skip 'J'
while(ed > calendar::end_of_month_day(year,em)){
ed -= calendar::end_of_month_day(year,em++);
}
dst_calc_rules_ = shared_ptr<dst_calc_rule>(
new partial_date_dst_rule(
partial_date_dst_rule::start_rule(
sd, static_cast<date_time::months_of_year>(sm)),
partial_date_dst_rule::end_rule(
ed, static_cast<date_time::months_of_year>(em))
)
);
}
//! Julian day. Feb29 is always counted, but exception thrown in non-leap years
// expects range of 0-365
void julian_day(const string_type& s, const string_type& e){
int sd=0, ed=0;
sd = lexical_cast<int>(s);
ed = lexical_cast<int>(e);
dst_calc_rules_ = shared_ptr<dst_calc_rule>(
new partial_date_dst_rule(
partial_date_dst_rule::start_rule(++sd),// args are 0-365
partial_date_dst_rule::end_rule(++ed) // pd expects 1-366
)
);
}
//! helper function used when throwing exceptions
static std::string td_as_string(const time_duration_type& td)
{
std::string s;
#if defined(USE_DATE_TIME_PRE_1_33_FACET_IO)
s = posix_time::to_simple_string(td);
#else
std::stringstream ss;
ss << td;
s = ss.str();
#endif
return s;
}
};
typedef posix_time_zone_base<char> posix_time_zone;
} } // namespace boost::local_time
#endif // _DATE_TIME_POSIX_TIME_ZONE__
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