1 2 #ifndef DATETIME_PERIOD_PARSER_HPP___ 3 #define DATETIME_PERIOD_PARSER_HPP___ 4 5 /* Copyright (c) 2002-2004 CrystalClear Software, Inc. 6 * Use, modification and distribution is subject to the 7 * Boost Software License, Version 1.0. (See accompanying 8 * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt) 9 * Author: Jeff Garland, Bart Garst 10 * $Date$ 11 */ 12 13 #include <ios> 14 #include <string> 15 #include <vector> 16 #include <iterator> 17 #include <boost/throw_exception.hpp> 18 #include <boost/date_time/special_defs.hpp> 19 #include <boost/date_time/string_parse_tree.hpp> 20 #include <boost/date_time/string_convert.hpp> 21 22 23 namespace boost { namespace date_time { 24 25 26 //! Not a facet, but a class used to specify and control period parsing 27 /*! Provides settings for the following: 28 * - period_separator -- default '/' 29 * - period_open_start_delimeter -- default '[' 30 * - period_open_range_end_delimeter -- default ')' 31 * - period_closed_range_end_delimeter -- default ']' 32 * - display_as_open_range, display_as_closed_range -- default closed_range 33 * 34 * For a typical date_period, the contents of the input stream would be 35 *@code 36 * [2004-Jan-04/2004-Feb-01] 37 *@endcode 38 * where the date format is controlled by the date facet 39 */ 40 template<class date_type, typename CharT> 41 class period_parser { 42 public: 43 typedef std::basic_string<CharT> string_type; 44 typedef CharT char_type; 45 //typedef typename std::basic_string<char_type>::const_iterator const_itr_type; 46 typedef std::istreambuf_iterator<CharT> stream_itr_type; 47 typedef string_parse_tree<CharT> parse_tree_type; 48 typedef typename parse_tree_type::parse_match_result_type match_results; 49 typedef std::vector<std::basic_string<CharT> > collection_type; 50 51 static const char_type default_period_separator[2]; 52 static const char_type default_period_start_delimeter[2]; 53 static const char_type default_period_open_range_end_delimeter[2]; 54 static const char_type default_period_closed_range_end_delimeter[2]; 55 56 enum period_range_option { AS_OPEN_RANGE, AS_CLOSED_RANGE }; 57 58 //! Constructor that sets up period parser options period_parser(period_range_option range_opt=AS_CLOSED_RANGE,const char_type * const period_separator=default_period_separator,const char_type * const period_start_delimeter=default_period_start_delimeter,const char_type * const period_open_range_end_delimeter=default_period_open_range_end_delimeter,const char_type * const period_closed_range_end_delimeter=default_period_closed_range_end_delimeter)59 period_parser(period_range_option range_opt = AS_CLOSED_RANGE, 60 const char_type* const period_separator = default_period_separator, 61 const char_type* const period_start_delimeter = default_period_start_delimeter, 62 const char_type* const period_open_range_end_delimeter = default_period_open_range_end_delimeter, 63 const char_type* const period_closed_range_end_delimeter = default_period_closed_range_end_delimeter) 64 : m_range_option(range_opt) 65 { 66 delimiters.push_back(string_type(period_separator)); 67 delimiters.push_back(string_type(period_start_delimeter)); 68 delimiters.push_back(string_type(period_open_range_end_delimeter)); 69 delimiters.push_back(string_type(period_closed_range_end_delimeter)); 70 } 71 range_option() const72 period_range_option range_option() const 73 { 74 return m_range_option; 75 } range_option(period_range_option option)76 void range_option(period_range_option option) 77 { 78 m_range_option = option; 79 } delimiter_strings() const80 collection_type delimiter_strings() const 81 { 82 return delimiters; 83 } delimiter_strings(const string_type & separator,const string_type & start_delim,const string_type & open_end_delim,const string_type & closed_end_delim)84 void delimiter_strings(const string_type& separator, 85 const string_type& start_delim, 86 const string_type& open_end_delim, 87 const string_type& closed_end_delim) 88 { 89 delimiters.clear(); 90 delimiters.push_back(separator); 91 delimiters.push_back(start_delim); 92 delimiters.push_back(open_end_delim); 93 delimiters.push_back(closed_end_delim); 94 } 95 96 //! Generic code to parse a period -- no matter the period type. 97 /*! This generic code will parse any period using a facet to 98 * to get the 'elements'. For example, in the case of a date_period 99 * the elements will be instances of a date which will be parsed 100 * according the to setup in the passed facet parameter. 101 * 102 * The steps for parsing a period are always the same: 103 * - consume the start delimiter 104 * - get start element 105 * - consume the separator 106 * - get either last or end element depending on range settings 107 * - consume the end delimeter depending on range settings 108 * 109 * Thus for a typical date period the contents of the input stream 110 * might look like this: 111 *@code 112 * 113 * [March 01, 2004/June 07, 2004] <-- closed range 114 * [March 01, 2004/June 08, 2004) <-- open range 115 * 116 *@endcode 117 */ 118 template<class period_type, class duration_type, class facet_type> 119 period_type get_period(stream_itr_type& sitr, 120 stream_itr_type& stream_end, 121 std::ios_base& a_ios, 122 const period_type& /* p */, 123 const duration_type& dur_unit, 124 const facet_type& facet) const 125 { 126 // skip leading whitespace 127 while(std::isspace(*sitr) && sitr != stream_end) { ++sitr; } 128 129 typedef typename period_type::point_type point_type; 130 point_type p1(not_a_date_time), p2(not_a_date_time); 131 132 133 consume_delim(sitr, stream_end, delimiters[START]); // start delim 134 facet.get(sitr, stream_end, a_ios, p1); // first point 135 consume_delim(sitr, stream_end, delimiters[SEPARATOR]); // separator 136 facet.get(sitr, stream_end, a_ios, p2); // second point 137 138 // period construction parameters are always open range [begin, end) 139 if (m_range_option == AS_CLOSED_RANGE) { 140 consume_delim(sitr, stream_end, delimiters[CLOSED_END]);// end delim 141 // add 1 duration unit to p2 to make range open 142 p2 += dur_unit; 143 } 144 else { 145 consume_delim(sitr, stream_end, delimiters[OPEN_END]); // end delim 146 } 147 148 return period_type(p1, p2); 149 } 150 151 private: 152 collection_type delimiters; 153 period_range_option m_range_option; 154 155 enum delim_ids { SEPARATOR, START, OPEN_END, CLOSED_END }; 156 157 //! throws ios_base::failure if delimiter and parsed data do not match consume_delim(stream_itr_type & sitr,stream_itr_type & stream_end,const string_type & delim) const158 void consume_delim(stream_itr_type& sitr, 159 stream_itr_type& stream_end, 160 const string_type& delim) const 161 { 162 /* string_parse_tree will not parse a string of punctuation characters 163 * without knowing exactly how many characters to process 164 * Ex [2000. Will not parse out the '[' string without knowing 165 * to process only one character. By using length of the delimiter 166 * string we can safely iterate past it. */ 167 string_type s; 168 for(unsigned int i = 0; i < delim.length() && sitr != stream_end; ++i) { 169 s += *sitr; 170 ++sitr; 171 } 172 if(s != delim) { 173 boost::throw_exception(std::ios_base::failure("Parse failed. Expected '" 174 + convert_string_type<char_type,char>(delim) + "' but found '" + convert_string_type<char_type,char>(s) + "'")); 175 } 176 } 177 }; 178 179 template <class date_type, class char_type> 180 const typename period_parser<date_type, char_type>::char_type 181 period_parser<date_type, char_type>::default_period_separator[2] = {'/'}; 182 183 template <class date_type, class char_type> 184 const typename period_parser<date_type, char_type>::char_type 185 period_parser<date_type, char_type>::default_period_start_delimeter[2] = {'['}; 186 187 template <class date_type, class char_type> 188 const typename period_parser<date_type, char_type>::char_type 189 period_parser<date_type, char_type>::default_period_open_range_end_delimeter[2] = {')'}; 190 191 template <class date_type, class char_type> 192 const typename period_parser<date_type, char_type>::char_type 193 period_parser<date_type, char_type>::default_period_closed_range_end_delimeter[2] = {']'}; 194 195 } } //namespace boost::date_time 196 197 #endif // DATETIME_PERIOD_PARSER_HPP___ 198