ext-boost/boost/date_time/date_parsing.hpp

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2019-08-24 13:39:04 +00:00
#ifndef _DATE_TIME_DATE_PARSING_HPP___
#define _DATE_TIME_DATE_PARSING_HPP___
/* Copyright (c) 2002,2003,2005 CrystalClear Software, Inc.
* Use, modification and distribution is 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
* $Date$
*/
#include <string>
#include <iterator>
#include <algorithm>
#include <boost/tokenizer.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/date_time/compiler_config.hpp>
#include <boost/date_time/parse_format_base.hpp>
#if defined(BOOST_DATE_TIME_NO_LOCALE)
#include <cctype> // ::tolower(int)
#else
#include <locale> // std::tolower(char, locale)
#endif
namespace boost {
namespace date_time {
//! A function to replace the std::transform( , , ,tolower) construct
/*! This function simply takes a string, and changes all the characters
* in that string to lowercase (according to the default system locale).
* In the event that a compiler does not support locales, the old
* C style tolower() is used.
*/
inline
std::string
convert_to_lower(std::string inp)
{
#if !defined(BOOST_DATE_TIME_NO_LOCALE)
const std::locale loc(std::locale::classic());
#endif
std::string::size_type i = 0, n = inp.length();
for (; i < n; ++i) {
inp[i] =
#if defined(BOOST_DATE_TIME_NO_LOCALE)
static_cast<char>(std::tolower(inp[i]));
#else
// tolower and others were brought in to std for borland >= v564
// in compiler_config.hpp
std::tolower(inp[i], loc);
#endif
}
return inp;
}
//! Helper function for parse_date.
/* Used by-value parameter because we change the string and may
* want to preserve the original argument */
template<class month_type>
inline unsigned short
month_str_to_ushort(std::string const& s) {
if((s.at(0) >= '0') && (s.at(0) <= '9')) {
return boost::lexical_cast<unsigned short>(s);
}
else {
std::string str = convert_to_lower(s);
typename month_type::month_map_ptr_type ptr = month_type::get_month_map_ptr();
typename month_type::month_map_type::iterator iter = ptr->find(str);
if(iter != ptr->end()) { // required for STLport
return iter->second;
}
}
return 13; // intentionally out of range - name not found
}
//! Find index of a string in either of 2 arrays
/*! find_match searches both arrays for a match to 's'. Both arrays
* must contain 'size' elements. The index of the match is returned.
* If no match is found, 'size' is returned.
* Ex. "Jan" returns 0, "Dec" returns 11, "Tue" returns 2.
* 'size' can be sent in with: (greg_month::max)() (which 12),
* (greg_weekday::max)() + 1 (which is 7) or date_time::NumSpecialValues */
template<class charT>
short find_match(const charT* const* short_names,
const charT* const* long_names,
short size,
const std::basic_string<charT>& s) {
for(short i = 0; i < size; ++i){
if(short_names[i] == s || long_names[i] == s){
return i;
}
}
return size; // not-found, return a value out of range
}
//! Generic function to parse a delimited date (eg: 2002-02-10)
/*! Accepted formats are: "2003-02-10" or " 2003-Feb-10" or
* "2003-Feburary-10"
* The order in which the Month, Day, & Year appear in the argument
* string can be accomodated by passing in the appropriate ymd_order_spec
*/
template<class date_type>
date_type
parse_date(const std::string& s, int order_spec = ymd_order_iso) {
std::string spec_str;
if(order_spec == ymd_order_iso) {
spec_str = "ymd";
}
else if(order_spec == ymd_order_dmy) {
spec_str = "dmy";
}
else { // (order_spec == ymd_order_us)
spec_str = "mdy";
}
typedef typename date_type::month_type month_type;
unsigned pos = 0;
unsigned short year(0), month(0), day(0);
typedef typename std::basic_string<char>::traits_type traits_type;
typedef boost::char_separator<char, traits_type> char_separator_type;
typedef boost::tokenizer<char_separator_type,
std::basic_string<char>::const_iterator,
std::basic_string<char> > tokenizer;
typedef boost::tokenizer<char_separator_type,
std::basic_string<char>::const_iterator,
std::basic_string<char> >::iterator tokenizer_iterator;
// may need more delimiters, these work for the regression tests
const char sep_char[] = {',','-','.',' ','/','\0'};
char_separator_type sep(sep_char);
tokenizer tok(s,sep);
for(tokenizer_iterator beg=tok.begin();
beg!=tok.end() && pos < spec_str.size();
++beg, ++pos) {
switch(spec_str.at(pos)) {
case 'y':
{
year = boost::lexical_cast<unsigned short>(*beg);
break;
}
case 'm':
{
month = month_str_to_ushort<month_type>(*beg);
break;
}
case 'd':
{
day = boost::lexical_cast<unsigned short>(*beg);
break;
}
default: break;
} //switch
}
return date_type(year, month, day);
}
//! Generic function to parse undelimited date (eg: 20020201)
template<class date_type>
date_type
parse_undelimited_date(const std::string& s) {
int offsets[] = {4,2,2};
int pos = 0;
//typename date_type::ymd_type ymd((year_type::min)(),1,1);
unsigned short y = 0, m = 0, d = 0;
/* The two bool arguments state that parsing will not wrap
* (only the first 8 characters will be parsed) and partial
* strings will not be parsed.
* Ex:
* "2005121" will parse 2005 & 12, but not the "1" */
boost::offset_separator osf(offsets, offsets+3, false, false);
typedef typename boost::tokenizer<boost::offset_separator,
std::basic_string<char>::const_iterator,
std::basic_string<char> > tokenizer_type;
tokenizer_type tok(s, osf);
for(typename tokenizer_type::iterator ti=tok.begin(); ti!=tok.end();++ti) {
unsigned short i = boost::lexical_cast<unsigned short>(*ti);
switch(pos) {
case 0: y = i; break;
case 1: m = i; break;
case 2: d = i; break;
default: break;
}
pos++;
}
return date_type(y,m,d);
}
//! Helper function for 'date gregorian::from_stream()'
/*! Creates a string from the iterators that reference the
* begining & end of a char[] or string. All elements are
* used in output string */
template<class date_type, class iterator_type>
inline
date_type
from_stream_type(iterator_type& beg,
iterator_type const& end,
char)
{
std::ostringstream ss;
while(beg != end) {
ss << *beg++;
}
return parse_date<date_type>(ss.str());
}
//! Helper function for 'date gregorian::from_stream()'
/*! Returns the first string found in the stream referenced by the
* begining & end iterators */
template<class date_type, class iterator_type>
inline
date_type
from_stream_type(iterator_type& beg,
iterator_type const& /* end */,
std::string const&)
{
return parse_date<date_type>(*beg);
}
/* I believe the wchar stuff would be best elsewhere, perhaps in
* parse_date<>()? In the mean time this gets us started... */
//! Helper function for 'date gregorian::from_stream()'
/*! Creates a string from the iterators that reference the
* begining & end of a wstring. All elements are
* used in output string */
template<class date_type, class iterator_type>
inline
date_type from_stream_type(iterator_type& beg,
iterator_type const& end,
wchar_t)
{
std::ostringstream ss;
#if !defined(BOOST_DATE_TIME_NO_LOCALE)
std::locale loc;
std::ctype<wchar_t> const& fac = std::use_facet<std::ctype<wchar_t> >(loc);
while(beg != end) {
ss << fac.narrow(*beg++, 'X'); // 'X' will cause exception to be thrown
}
#else
while(beg != end) {
char c = 'X'; // 'X' will cause exception to be thrown
const wchar_t wc = *beg++;
if (wc >= 0 && wc <= 127)
c = static_cast< char >(wc);
ss << c;
}
#endif
return parse_date<date_type>(ss.str());
}
#ifndef BOOST_NO_STD_WSTRING
//! Helper function for 'date gregorian::from_stream()'
/*! Creates a string from the first wstring found in the stream
* referenced by the begining & end iterators */
template<class date_type, class iterator_type>
inline
date_type
from_stream_type(iterator_type& beg,
iterator_type const& /* end */,
std::wstring const&) {
std::wstring ws = *beg;
std::ostringstream ss;
std::wstring::iterator wsb = ws.begin(), wse = ws.end();
#if !defined(BOOST_DATE_TIME_NO_LOCALE)
std::locale loc;
std::ctype<wchar_t> const& fac = std::use_facet<std::ctype<wchar_t> >(loc);
while(wsb != wse) {
ss << fac.narrow(*wsb++, 'X'); // 'X' will cause exception to be thrown
}
#else
while(wsb != wse) {
char c = 'X'; // 'X' will cause exception to be thrown
const wchar_t wc = *wsb++;
if (wc >= 0 && wc <= 127)
c = static_cast< char >(wc);
ss << c;
}
#endif
return parse_date<date_type>(ss.str());
}
#endif // BOOST_NO_STD_WSTRING
#if (defined(BOOST_MSVC) && (_MSC_VER < 1300))
// This function cannot be compiled with MSVC 6.0 due to internal compiler shorcomings
#else
//! function called by wrapper functions: date_period_from_(w)string()
template<class date_type, class charT>
period<date_type, typename date_type::duration_type>
from_simple_string_type(const std::basic_string<charT>& s){
typedef typename std::basic_string<charT>::traits_type traits_type;
typedef typename boost::char_separator<charT, traits_type> char_separator;
typedef typename boost::tokenizer<char_separator,
typename std::basic_string<charT>::const_iterator,
std::basic_string<charT> > tokenizer;
const charT sep_list[4] = {'[','/',']','\0'};
char_separator sep(sep_list);
tokenizer tokens(s, sep);
typename tokenizer::iterator tok_it = tokens.begin();
std::basic_string<charT> date_string = *tok_it;
// get 2 string iterators and generate a date from them
typename std::basic_string<charT>::iterator date_string_start = date_string.begin(),
date_string_end = date_string.end();
typedef typename std::iterator_traits<typename std::basic_string<charT>::iterator>::value_type value_type;
date_type d1 = from_stream_type<date_type>(date_string_start, date_string_end, value_type());
date_string = *(++tok_it); // next token
date_string_start = date_string.begin(), date_string_end = date_string.end();
date_type d2 = from_stream_type<date_type>(date_string_start, date_string_end, value_type());
return period<date_type, typename date_type::duration_type>(d1, d2);
}
#endif
} } //namespace date_time
#endif