libstdc++
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00001 // class template regex -*- C++ -*- 00002 00003 // Copyright (C) 2013-2014 Free Software Foundation, Inc. 00004 // 00005 // This file is part of the GNU ISO C++ Library. This library is free 00006 // software; you can redistribute it and/or modify it under the 00007 // terms of the GNU General Public License as published by the 00008 // Free Software Foundation; either version 3, or (at your option) 00009 // any later version. 00010 00011 // This library is distributed in the hope that it will be useful, 00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00014 // GNU General Public License for more details. 00015 00016 // Under Section 7 of GPL version 3, you are granted additional 00017 // permissions described in the GCC Runtime Library Exception, version 00018 // 3.1, as published by the Free Software Foundation. 00019 00020 // You should have received a copy of the GNU General Public License and 00021 // a copy of the GCC Runtime Library Exception along with this program; 00022 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 00023 // <http://www.gnu.org/licenses/>. 00024 00025 /** 00026 * @file bits/regex_scanner.h 00027 * This is an internal header file, included by other library headers. 00028 * Do not attempt to use it directly. @headername{regex} 00029 */ 00030 00031 namespace std _GLIBCXX_VISIBILITY(default) 00032 { 00033 namespace __detail 00034 { 00035 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00036 00037 /** 00038 * @addtogroup regex-detail 00039 * @{ 00040 */ 00041 00042 struct _ScannerBase 00043 { 00044 public: 00045 /// Token types returned from the scanner. 00046 enum _TokenT 00047 { 00048 _S_token_anychar, 00049 _S_token_ord_char, 00050 _S_token_oct_num, 00051 _S_token_hex_num, 00052 _S_token_backref, 00053 _S_token_subexpr_begin, 00054 _S_token_subexpr_no_group_begin, 00055 _S_token_subexpr_lookahead_begin, // neg if _M_value[0] == 'n' 00056 _S_token_subexpr_end, 00057 _S_token_bracket_begin, 00058 _S_token_bracket_neg_begin, 00059 _S_token_bracket_end, 00060 _S_token_interval_begin, 00061 _S_token_interval_end, 00062 _S_token_quoted_class, 00063 _S_token_char_class_name, 00064 _S_token_collsymbol, 00065 _S_token_equiv_class_name, 00066 _S_token_opt, 00067 _S_token_or, 00068 _S_token_closure0, 00069 _S_token_closure1, 00070 _S_token_ungreedy, 00071 _S_token_line_begin, 00072 _S_token_line_end, 00073 _S_token_word_bound, // neg if _M_value[0] == 'n' 00074 _S_token_comma, 00075 _S_token_dup_count, 00076 _S_token_eof, 00077 _S_token_unknown 00078 }; 00079 00080 protected: 00081 typedef regex_constants::syntax_option_type _FlagT; 00082 00083 enum _StateT 00084 { 00085 _S_state_normal, 00086 _S_state_in_brace, 00087 _S_state_in_bracket, 00088 }; 00089 00090 protected: 00091 _ScannerBase(_FlagT __flags) 00092 : _M_state(_S_state_normal), 00093 _M_flags(__flags), 00094 _M_escape_tbl(_M_is_ecma() 00095 ? _M_ecma_escape_tbl 00096 : _M_awk_escape_tbl), 00097 _M_spec_char(_M_is_ecma() 00098 ? _M_ecma_spec_char 00099 : _M_is_basic() 00100 ? _M_basic_spec_char 00101 : _M_extended_spec_char), 00102 _M_at_bracket_start(false) 00103 { } 00104 00105 protected: 00106 const char* 00107 _M_find_escape(char __c) 00108 { 00109 auto __it = _M_escape_tbl; 00110 for (; __it->first != '\0'; ++__it) 00111 if (__it->first == __c) 00112 return &__it->second; 00113 return nullptr; 00114 } 00115 00116 bool 00117 _M_is_ecma() const 00118 { return _M_flags & regex_constants::ECMAScript; } 00119 00120 bool 00121 _M_is_basic() const 00122 { return _M_flags & (regex_constants::basic | regex_constants::grep); } 00123 00124 bool 00125 _M_is_extended() const 00126 { 00127 return _M_flags & (regex_constants::extended 00128 | regex_constants::egrep 00129 | regex_constants::awk); 00130 } 00131 00132 bool 00133 _M_is_grep() const 00134 { return _M_flags & (regex_constants::grep | regex_constants::egrep); } 00135 00136 bool 00137 _M_is_awk() const 00138 { return _M_flags & regex_constants::awk; } 00139 00140 protected: 00141 const std::pair<char, _TokenT> _M_token_tbl[9] = 00142 { 00143 {'^', _S_token_line_begin}, 00144 {'$', _S_token_line_end}, 00145 {'.', _S_token_anychar}, 00146 {'*', _S_token_closure0}, 00147 {'+', _S_token_closure1}, 00148 {'?', _S_token_opt}, 00149 {'|', _S_token_or}, 00150 {'\n', _S_token_or}, // grep and egrep 00151 {'\0', _S_token_or}, 00152 }; 00153 const std::pair<char, char> _M_ecma_escape_tbl[8] = 00154 { 00155 {'0', '\0'}, 00156 {'b', '\b'}, 00157 {'f', '\f'}, 00158 {'n', '\n'}, 00159 {'r', '\r'}, 00160 {'t', '\t'}, 00161 {'v', '\v'}, 00162 {'\0', '\0'}, 00163 }; 00164 const std::pair<char, char> _M_awk_escape_tbl[11] = 00165 { 00166 {'"', '"'}, 00167 {'/', '/'}, 00168 {'\\', '\\'}, 00169 {'a', '\a'}, 00170 {'b', '\b'}, 00171 {'f', '\f'}, 00172 {'n', '\n'}, 00173 {'r', '\r'}, 00174 {'t', '\t'}, 00175 {'v', '\v'}, 00176 {'\0', '\0'}, 00177 }; 00178 const char* _M_ecma_spec_char = "^$\\.*+?()[]{}|"; 00179 const char* _M_basic_spec_char = ".[\\*^$"; 00180 const char* _M_extended_spec_char = ".[\\()*+?{|^$"; 00181 00182 _StateT _M_state; 00183 _FlagT _M_flags; 00184 _TokenT _M_token; 00185 const std::pair<char, char>* _M_escape_tbl; 00186 const char* _M_spec_char; 00187 bool _M_at_bracket_start; 00188 }; 00189 00190 /** 00191 * @brief Scans an input range for regex tokens. 00192 * 00193 * The %_Scanner class interprets the regular expression pattern in 00194 * the input range passed to its constructor as a sequence of parse 00195 * tokens passed to the regular expression compiler. The sequence 00196 * of tokens provided depends on the flag settings passed to the 00197 * constructor: different regular expression grammars will interpret 00198 * the same input pattern in syntactically different ways. 00199 */ 00200 template<typename _CharT> 00201 class _Scanner 00202 : public _ScannerBase 00203 { 00204 public: 00205 typedef const _CharT* _IterT; 00206 typedef std::basic_string<_CharT> _StringT; 00207 typedef regex_constants::syntax_option_type _FlagT; 00208 typedef const std::ctype<_CharT> _CtypeT; 00209 00210 _Scanner(_IterT __begin, _IterT __end, 00211 _FlagT __flags, std::locale __loc); 00212 00213 void 00214 _M_advance(); 00215 00216 _TokenT 00217 _M_get_token() const 00218 { return _M_token; } 00219 00220 const _StringT& 00221 _M_get_value() const 00222 { return _M_value; } 00223 00224 #ifdef _GLIBCXX_DEBUG 00225 std::ostream& 00226 _M_print(std::ostream&); 00227 #endif 00228 00229 private: 00230 void 00231 _M_scan_normal(); 00232 00233 void 00234 _M_scan_in_bracket(); 00235 00236 void 00237 _M_scan_in_brace(); 00238 00239 void 00240 _M_eat_escape_ecma(); 00241 00242 void 00243 _M_eat_escape_posix(); 00244 00245 void 00246 _M_eat_escape_awk(); 00247 00248 void 00249 _M_eat_class(char); 00250 00251 _IterT _M_current; 00252 _IterT _M_end; 00253 _CtypeT& _M_ctype; 00254 _StringT _M_value; 00255 void (_Scanner::* _M_eat_escape)(); 00256 }; 00257 00258 //@} regex-detail 00259 _GLIBCXX_END_NAMESPACE_VERSION 00260 } // namespace __detail 00261 } // namespace std 00262 00263 #include <bits/regex_scanner.tcc>