boost/regex/v4/basic_regex_parser.hpp
/* * * Copyright (c) 2004 * John Maddock * * Use, modification and distribution are subject to the * Boost Software License, Version 1.0. (See accompanying file * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) * */ /* * LOCATION: see http://www.boost.org for most recent version. * FILE basic_regex_parser.cpp * VERSION see <boost/version.hpp> * DESCRIPTION: Declares template class basic_regex_parser. */ #ifndef BOOST_REGEX_V4_BASIC_REGEX_PARSER_HPP #define BOOST_REGEX_V4_BASIC_REGEX_PARSER_HPP #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable: 4103) #endif #ifdef BOOST_HAS_ABI_HEADERS # include BOOST_ABI_PREFIX #endif #ifdef BOOST_MSVC #pragma warning(pop) #endif namespace boost{ namespace re_detail{ #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable:4244 4800) #endif template <class charT, class traits> class basic_regex_parser : public basic_regex_creator<charT, traits> { public: basic_regex_parser(regex_data<charT, traits>* data); void parse(const charT* p1, const charT* p2, unsigned flags); void fail(regex_constants::error_type error_code, std::ptrdiff_t position); void fail(regex_constants::error_type error_code, std::ptrdiff_t position, std::string message, std::ptrdiff_t start_pos); void fail(regex_constants::error_type error_code, std::ptrdiff_t position, const std::string& message) { fail(error_code, position, message, position); } bool parse_all(); bool parse_basic(); bool parse_extended(); bool parse_literal(); bool parse_open_paren(); bool parse_basic_escape(); bool parse_extended_escape(); bool parse_match_any(); bool parse_repeat(std::size_t low = 0, std::size_t high = (std::numeric_limits<std::size_t>::max)()); bool parse_repeat_range(bool isbasic); bool parse_alt(); bool parse_set(); bool parse_backref(); void parse_set_literal(basic_char_set<charT, traits>& char_set); bool parse_inner_set(basic_char_set<charT, traits>& char_set); bool parse_QE(); bool parse_perl_extension(); bool add_emacs_code(bool negate); bool unwind_alts(std::ptrdiff_t last_paren_start); digraph<charT> get_next_set_literal(basic_char_set<charT, traits>& char_set); charT unescape_character(); regex_constants::syntax_option_type parse_options(); private: typedef bool (basic_regex_parser::*parser_proc_type)(); typedef typename traits::string_type string_type; typedef typename traits::char_class_type char_class_type; parser_proc_type m_parser_proc; // the main parser to use const charT* m_base; // the start of the string being parsed const charT* m_end; // the end of the string being parsed const charT* m_position; // our current parser position unsigned m_mark_count; // how many sub-expressions we have int m_mark_reset; // used to indicate that we're inside a (?|...) block. unsigned m_max_mark; // largest mark count seen inside a (?|...) block. std::ptrdiff_t m_paren_start; // where the last seen ')' began (where repeats are inserted). std::ptrdiff_t m_alt_insert_point; // where to insert the next alternative bool m_has_case_change; // true if somewhere in the current block the case has changed #if defined(BOOST_MSVC) && defined(_M_IX86) // This is an ugly warning suppression workaround (for warnings *inside* std::vector // that can not otherwise be suppressed)... BOOST_STATIC_ASSERT(sizeof(long) >= sizeof(void*)); std::vector<long> m_alt_jumps; // list of alternative in the current scope. #else std::vector<std::ptrdiff_t> m_alt_jumps; // list of alternative in the current scope. #endif basic_regex_parser& operator=(const basic_regex_parser&); basic_regex_parser(const basic_regex_parser&); }; template <class charT, class traits> basic_regex_parser<charT, traits>::basic_regex_parser(regex_data<charT, traits>* data) : basic_regex_creator<charT, traits>(data), m_mark_count(0), m_mark_reset(-1), m_max_mark(0), m_paren_start(0), m_alt_insert_point(0), m_has_case_change(false) { } template <class charT, class traits> void basic_regex_parser<charT, traits>::parse(const charT* p1, const charT* p2, unsigned l_flags) { // pass l_flags on to base class: this->init(l_flags); // set up pointers: m_position = m_base = p1; m_end = p2; // empty strings are errors: if((p1 == p2) && ( ((l_flags & regbase::main_option_type) != regbase::perl_syntax_group) || (l_flags & regbase::no_empty_expressions) ) ) { fail(regex_constants::error_empty, 0); return; } // select which parser to use: switch(l_flags & regbase::main_option_type) { case regbase::perl_syntax_group: { m_parser_proc = &basic_regex_parser<charT, traits>::parse_extended; // // Add a leading paren with index zero to give recursions a target: // re_brace* br = static_cast<re_brace*>(this->append_state(syntax_element_startmark, sizeof(re_brace))); br->index = 0; br->icase = this->flags() & regbase::icase; break; } case regbase::basic_syntax_group: m_parser_proc = &basic_regex_parser<charT, traits>::parse_basic; break; case regbase::literal: m_parser_proc = &basic_regex_parser<charT, traits>::parse_literal; break; default: // Ooops, someone has managed to set more than one of the main option flags, // so this must be an error: fail(regex_constants::error_unknown, 0, "An invalid combination of regular expression syntax flags was used."); return; } // parse all our characters: bool result = parse_all(); // // Unwind our alternatives: // unwind_alts(-1); // reset l_flags as a global scope (?imsx) may have altered them: this->flags(l_flags); // if we haven't gobbled up all the characters then we must // have had an unexpected ')' : if(!result) { fail(regex_constants::error_paren, ::boost::re_detail::distance(m_base, m_position), "Found a closing ) with no corresponding openening parenthesis."); return; } // if an error has been set then give up now: if(this->m_pdata->m_status) return; // fill in our sub-expression count: this->m_pdata->m_mark_count = 1 + m_mark_count; this->finalize(p1, p2); } template <class charT, class traits> void basic_regex_parser<charT, traits>::fail(regex_constants::error_type error_code, std::ptrdiff_t position) { // get the error message: std::string message = this->m_pdata->m_ptraits->error_string(error_code); fail(error_code, position, message); } template <class charT, class traits> void basic_regex_parser<charT, traits>::fail(regex_constants::error_type error_code, std::ptrdiff_t position, std::string message, std::ptrdiff_t start_pos) { if(0 == this->m_pdata->m_status) // update the error code if not already set this->m_pdata->m_status = error_code; m_position = m_end; // don't bother parsing anything else // // Augment error message with the regular expression text: // if(start_pos == position) start_pos = (std::max)(static_cast<std::ptrdiff_t>(0), position - static_cast<std::ptrdiff_t>(10)); std::ptrdiff_t end_pos = (std::min)(position + static_cast<std::ptrdiff_t>(10), static_cast<std::ptrdiff_t>(m_end - m_base)); if(error_code != regex_constants::error_empty) { if((start_pos != 0) || (end_pos != (m_end - m_base))) message += " The error occured while parsing the regular expression fragment: '"; else message += " The error occured while parsing the regular expression: '"; if(start_pos != end_pos) { message += std::string(m_base + start_pos, m_base + position); message += ">>>HERE>>>"; message += std::string(m_base + position, m_base + end_pos); } message += "'."; } #ifndef BOOST_NO_EXCEPTIONS if(0 == (this->flags() & regex_constants::no_except)) { boost::regex_error e(message, error_code, position); e.raise(); } #else (void)position; // suppress warnings. #endif } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_all() { bool result = true; while(result && (m_position != m_end)) { result = (this->*m_parser_proc)(); } return result; } #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable:4702) #endif template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_basic() { switch(this->m_traits.syntax_type(*m_position)) { case regex_constants::syntax_escape: return parse_basic_escape(); case regex_constants::syntax_dot: return parse_match_any(); case regex_constants::syntax_caret: ++m_position; this->append_state(syntax_element_start_line); break; case regex_constants::syntax_dollar: ++m_position; this->append_state(syntax_element_end_line); break; case regex_constants::syntax_star: if(!(this->m_last_state) || (this->m_last_state->type == syntax_element_start_line)) return parse_literal(); else { ++m_position; return parse_repeat(); } case regex_constants::syntax_plus: if(!(this->m_last_state) || (this->m_last_state->type == syntax_element_start_line) || !(this->flags() & regbase::emacs_ex)) return parse_literal(); else { ++m_position; return parse_repeat(1); } case regex_constants::syntax_question: if(!(this->m_last_state) || (this->m_last_state->type == syntax_element_start_line) || !(this->flags() & regbase::emacs_ex)) return parse_literal(); else { ++m_position; return parse_repeat(0, 1); } case regex_constants::syntax_open_set: return parse_set(); case regex_constants::syntax_newline: if(this->flags() & regbase::newline_alt) return parse_alt(); else return parse_literal(); default: return parse_literal(); } return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_extended() { bool result = true; switch(this->m_traits.syntax_type(*m_position)) { case regex_constants::syntax_open_mark: return parse_open_paren(); case regex_constants::syntax_close_mark: return false; case regex_constants::syntax_escape: return parse_extended_escape(); case regex_constants::syntax_dot: return parse_match_any(); case regex_constants::syntax_caret: ++m_position; this->append_state( (this->flags() & regex_constants::no_mod_m ? syntax_element_buffer_start : syntax_element_start_line)); break; case regex_constants::syntax_dollar: ++m_position; this->append_state( (this->flags() & regex_constants::no_mod_m ? syntax_element_buffer_end : syntax_element_end_line)); break; case regex_constants::syntax_star: if(m_position == this->m_base) { fail(regex_constants::error_badrepeat, 0, "The repeat operator \"*\" cannot start a regular expression."); return false; } ++m_position; return parse_repeat(); case regex_constants::syntax_question: if(m_position == this->m_base) { fail(regex_constants::error_badrepeat, 0, "The repeat operator \"?\" cannot start a regular expression."); return false; } ++m_position; return parse_repeat(0,1); case regex_constants::syntax_plus: if(m_position == this->m_base) { fail(regex_constants::error_badrepeat, 0, "The repeat operator \"+\" cannot start a regular expression."); return false; } ++m_position; return parse_repeat(1); case regex_constants::syntax_open_brace: ++m_position; return parse_repeat_range(false); case regex_constants::syntax_close_brace: fail(regex_constants::error_brace, this->m_position - this->m_base, "Found a closing repetition operator } with no corresponding {."); return false; case regex_constants::syntax_or: return parse_alt(); case regex_constants::syntax_open_set: return parse_set(); case regex_constants::syntax_newline: if(this->flags() & regbase::newline_alt) return parse_alt(); else return parse_literal(); case regex_constants::syntax_hash: // // If we have a mod_x flag set, then skip until // we get to a newline character: // if((this->flags() & (regbase::no_perl_ex|regbase::mod_x)) == regbase::mod_x) { while((m_position != m_end) && !is_separator(*m_position++)){} return true; } // Otherwise fall through: default: result = parse_literal(); break; } return result; } #ifdef BOOST_MSVC #pragma warning(pop) #endif template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_literal() { // append this as a literal provided it's not a space character // or the perl option regbase::mod_x is not set: if( ((this->flags() & (regbase::main_option_type|regbase::mod_x|regbase::no_perl_ex)) != regbase::mod_x) || !this->m_traits.isctype(*m_position, this->m_mask_space)) this->append_literal(*m_position); ++m_position; return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_open_paren() { // // skip the '(' and error check: // if(++m_position == m_end) { fail(regex_constants::error_paren, m_position - m_base); return false; } // // begin by checking for a perl-style (?...) extension: // if( ((this->flags() & (regbase::main_option_type | regbase::no_perl_ex)) == 0) || ((this->flags() & (regbase::main_option_type | regbase::emacs_ex)) == (regbase::basic_syntax_group|regbase::emacs_ex)) ) { if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_question) return parse_perl_extension(); } // // update our mark count, and append the required state: // unsigned markid = 0; if(0 == (this->flags() & regbase::nosubs)) { markid = ++m_mark_count; #ifndef BOOST_NO_STD_DISTANCE if(this->flags() & regbase::save_subexpression_location) this->m_pdata->m_subs.push_back(std::pair<std::size_t, std::size_t>(std::distance(m_base, m_position) - 1, 0)); #else if(this->flags() & regbase::save_subexpression_location) this->m_pdata->m_subs.push_back(std::pair<std::size_t, std::size_t>((m_position - m_base) - 1, 0)); #endif } re_brace* pb = static_cast<re_brace*>(this->append_state(syntax_element_startmark, sizeof(re_brace))); pb->index = markid; pb->icase = this->flags() & regbase::icase; std::ptrdiff_t last_paren_start = this->getoffset(pb); // back up insertion point for alternations, and set new point: std::ptrdiff_t last_alt_point = m_alt_insert_point; this->m_pdata->m_data.align(); m_alt_insert_point = this->m_pdata->m_data.size(); // // back up the current flags in case we have a nested (?imsx) group: // regex_constants::syntax_option_type opts = this->flags(); bool old_case_change = m_has_case_change; m_has_case_change = false; // no changes to this scope as yet... // // Back up branch reset data in case we have a nested (?|...) // int mark_reset = m_mark_reset; m_mark_reset = -1; // // now recursively add more states, this will terminate when we get to a // matching ')' : // parse_all(); // // Unwind pushed alternatives: // if(0 == unwind_alts(last_paren_start)) return false; // // restore flags: // if(m_has_case_change) { // the case has changed in one or more of the alternatives // within the scoped (...) block: we have to add a state // to reset the case sensitivity: static_cast<re_case*>( this->append_state(syntax_element_toggle_case, sizeof(re_case)) )->icase = opts & regbase::icase; } this->flags(opts); m_has_case_change = old_case_change; // // restore branch reset: // m_mark_reset = mark_reset; // // we either have a ')' or we have run out of characters prematurely: // if(m_position == m_end) { this->fail(regex_constants::error_paren, ::boost::re_detail::distance(m_base, m_end)); return false; } BOOST_ASSERT(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_mark); #ifndef BOOST_NO_STD_DISTANCE if(markid && (this->flags() & regbase::save_subexpression_location)) this->m_pdata->m_subs.at(markid - 1).second = std::distance(m_base, m_position); #else if(markid && (this->flags() & regbase::save_subexpression_location)) this->m_pdata->m_subs.at(markid - 1).second = (m_position - m_base); #endif ++m_position; // // append closing parenthesis state: // pb = static_cast<re_brace*>(this->append_state(syntax_element_endmark, sizeof(re_brace))); pb->index = markid; pb->icase = this->flags() & regbase::icase; this->m_paren_start = last_paren_start; // // restore the alternate insertion point: // this->m_alt_insert_point = last_alt_point; // // allow backrefs to this mark: // if((markid > 0) && (markid < sizeof(unsigned) * CHAR_BIT)) this->m_backrefs |= 1u << (markid - 1); return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_basic_escape() { ++m_position; bool result = true; switch(this->m_traits.escape_syntax_type(*m_position)) { case regex_constants::syntax_open_mark: return parse_open_paren(); case regex_constants::syntax_close_mark: return false; case regex_constants::syntax_plus: if(this->flags() & regex_constants::bk_plus_qm) { ++m_position; return parse_repeat(1); } else return parse_literal(); case regex_constants::syntax_question: if(this->flags() & regex_constants::bk_plus_qm) { ++m_position; return parse_repeat(0, 1); } else return parse_literal(); case regex_constants::syntax_open_brace: if(this->flags() & regbase::no_intervals) return parse_literal(); ++m_position; return parse_repeat_range(true); case regex_constants::syntax_close_brace: if(this->flags() & regbase::no_intervals) return parse_literal(); fail(regex_constants::error_brace, this->m_position - this->m_base, "Found a closing repetition operator } with no corresponding {."); return false; case regex_constants::syntax_or: if(this->flags() & regbase::bk_vbar) return parse_alt(); else result = parse_literal(); break; case regex_constants::syntax_digit: return parse_backref(); case regex_constants::escape_type_start_buffer: if(this->flags() & regbase::emacs_ex) { ++m_position; this->append_state(syntax_element_buffer_start); } else result = parse_literal(); break; case regex_constants::escape_type_end_buffer: if(this->flags() & regbase::emacs_ex) { ++m_position; this->append_state(syntax_element_buffer_end); } else result = parse_literal(); break; case regex_constants::escape_type_word_assert: if(this->flags() & regbase::emacs_ex) { ++m_position; this->append_state(syntax_element_word_boundary); } else result = parse_literal(); break; case regex_constants::escape_type_not_word_assert: if(this->flags() & regbase::emacs_ex) { ++m_position; this->append_state(syntax_element_within_word); } else result = parse_literal(); break; case regex_constants::escape_type_left_word: if(this->flags() & regbase::emacs_ex) { ++m_position; this->append_state(syntax_element_word_start); } else result = parse_literal(); break; case regex_constants::escape_type_right_word: if(this->flags() & regbase::emacs_ex) { ++m_position; this->append_state(syntax_element_word_end); } else result = parse_literal(); break; default: if(this->flags() & regbase::emacs_ex) { bool negate = true; switch(*m_position) { case 'w': negate = false; // fall through: case 'W': { basic_char_set<charT, traits> char_set; if(negate) char_set.negate(); char_set.add_class(this->m_word_mask); if(0 == this->append_set(char_set)) { fail(regex_constants::error_ctype, m_position - m_base); return false; } ++m_position; return true; } case 's': negate = false; // fall through: case 'S': return add_emacs_code(negate); case 'c': case 'C': // not supported yet: fail(regex_constants::error_escape, m_position - m_base, "The \\c and \\C escape sequences are not supported by POSIX basic regular expressions: try the Perl syntax instead."); return false; default: break; } } result = parse_literal(); break; } return result; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_extended_escape() { ++m_position; bool negate = false; // in case this is a character class escape: \w \d etc switch(this->m_traits.escape_syntax_type(*m_position)) { case regex_constants::escape_type_not_class: negate = true; // fall through: case regex_constants::escape_type_class: { escape_type_class_jump: typedef typename traits::char_class_type mask_type; mask_type m = this->m_traits.lookup_classname(m_position, m_position+1); if(m != 0) { basic_char_set<charT, traits> char_set; if(negate) char_set.negate(); char_set.add_class(m); if(0 == this->append_set(char_set)) { fail(regex_constants::error_ctype, m_position - m_base); return false; } ++m_position; return true; } // // not a class, just a regular unknown escape: // this->append_literal(unescape_character()); break; } case regex_constants::syntax_digit: return parse_backref(); case regex_constants::escape_type_left_word: ++m_position; this->append_state(syntax_element_word_start); break; case regex_constants::escape_type_right_word: ++m_position; this->append_state(syntax_element_word_end); break; case regex_constants::escape_type_start_buffer: ++m_position; this->append_state(syntax_element_buffer_start); break; case regex_constants::escape_type_end_buffer: ++m_position; this->append_state(syntax_element_buffer_end); break; case regex_constants::escape_type_word_assert: ++m_position; this->append_state(syntax_element_word_boundary); break; case regex_constants::escape_type_not_word_assert: ++m_position; this->append_state(syntax_element_within_word); break; case regex_constants::escape_type_Z: ++m_position; this->append_state(syntax_element_soft_buffer_end); break; case regex_constants::escape_type_Q: return parse_QE(); case regex_constants::escape_type_C: return parse_match_any(); case regex_constants::escape_type_X: ++m_position; this->append_state(syntax_element_combining); break; case regex_constants::escape_type_G: ++m_position; this->append_state(syntax_element_restart_continue); break; case regex_constants::escape_type_not_property: negate = true; // fall through: case regex_constants::escape_type_property: { ++m_position; char_class_type m; if(m_position == m_end) { fail(regex_constants::error_escape, m_position - m_base, "Incomplete property escape found."); return false; } // maybe have \p{ddd} if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_open_brace) { const charT* base = m_position; // skip forward until we find enclosing brace: while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_brace)) ++m_position; if(m_position == m_end) { fail(regex_constants::error_escape, m_position - m_base, "Closing } missing from property escape sequence."); return false; } m = this->m_traits.lookup_classname(++base, m_position++); } else { m = this->m_traits.lookup_classname(m_position, m_position+1); ++m_position; } if(m != 0) { basic_char_set<charT, traits> char_set; if(negate) char_set.negate(); char_set.add_class(m); if(0 == this->append_set(char_set)) { fail(regex_constants::error_ctype, m_position - m_base); return false; } return true; } fail(regex_constants::error_ctype, m_position - m_base, "Escape sequence was neither a valid property nor a valid character class name."); return false; } case regex_constants::escape_type_reset_start_mark: if(0 == (this->flags() & (regbase::main_option_type | regbase::no_perl_ex))) { re_brace* pb = static_cast<re_brace*>(this->append_state(syntax_element_startmark, sizeof(re_brace))); pb->index = -5; pb->icase = this->flags() & regbase::icase; this->m_pdata->m_data.align(); ++m_position; return true; } goto escape_type_class_jump; case regex_constants::escape_type_line_ending: if(0 == (this->flags() & (regbase::main_option_type | regbase::no_perl_ex))) { const charT* e = get_escape_R_string<charT>(); const charT* old_position = m_position; const charT* old_end = m_end; const charT* old_base = m_base; m_position = e; m_base = e; m_end = e + traits::length(e); bool r = parse_all(); m_position = ++old_position; m_end = old_end; m_base = old_base; return r; } goto escape_type_class_jump; case regex_constants::escape_type_extended_backref: if(0 == (this->flags() & (regbase::main_option_type | regbase::no_perl_ex))) { bool have_brace = false; bool negative = false; static const char* incomplete_message = "Incomplete \\g escape found."; if(++m_position == m_end) { fail(regex_constants::error_escape, m_position - m_base, incomplete_message); return false; } // maybe have \g{ddd} if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_open_brace) { if(++m_position == m_end) { fail(regex_constants::error_escape, m_position - m_base, incomplete_message); return false; } have_brace = true; } negative = (*m_position == static_cast<charT>('-')); if((negative) && (++m_position == m_end)) { fail(regex_constants::error_escape, m_position - m_base, incomplete_message); return false; } const charT* pc = m_position; int i = this->m_traits.toi(pc, m_end, 10); if(i < 0) { // Check for a named capture: const charT* base = m_position; while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_brace)) ++m_position; i = this->m_pdata->get_id(base, m_position); pc = m_position; } if(negative) i = 1 + m_mark_count - i; if((i > 0) && (this->m_backrefs & (1u << (i-1)))) { m_position = pc; re_brace* pb = static_cast<re_brace*>(this->append_state(syntax_element_backref, sizeof(re_brace))); pb->index = i; pb->icase = this->flags() & regbase::icase; } else { fail(regex_constants::error_backref, m_position - m_base); return false; } m_position = pc; if(have_brace) { if((m_position == m_end) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_brace)) { fail(regex_constants::error_escape, m_position - m_base, incomplete_message); return false; } ++m_position; } return true; } goto escape_type_class_jump; case regex_constants::escape_type_control_v: if(0 == (this->flags() & (regbase::main_option_type | regbase::no_perl_ex))) goto escape_type_class_jump; // fallthrough: default: this->append_literal(unescape_character()); break; } return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_match_any() { // // we have a '.' that can match any character: // ++m_position; static_cast<re_dot*>( this->append_state(syntax_element_wild, sizeof(re_dot)) )->mask = static_cast<unsigned char>(this->flags() & regbase::no_mod_s ? re_detail::force_not_newline : this->flags() & regbase::mod_s ? re_detail::force_newline : re_detail::dont_care); return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_repeat(std::size_t low, std::size_t high) { bool greedy = true; bool pocessive = false; std::size_t insert_point; // // when we get to here we may have a non-greedy ? mark still to come: // if((m_position != m_end) && ( (0 == (this->flags() & (regbase::main_option_type | regbase::no_perl_ex))) || ((regbase::basic_syntax_group|regbase::emacs_ex) == (this->flags() & (regbase::main_option_type | regbase::emacs_ex))) ) ) { // OK we have a perl or emacs regex, check for a '?': if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_question) { greedy = false; ++m_position; } // for perl regexes only check for pocessive ++ repeats. if((0 == (this->flags() & regbase::main_option_type)) && (this->m_traits.syntax_type(*m_position) == regex_constants::syntax_plus)) { pocessive = true; ++m_position; } } if(0 == this->m_last_state) { fail(regex_constants::error_badrepeat, ::boost::re_detail::distance(m_base, m_position), "Nothing to repeat."); return false; } if(this->m_last_state->type == syntax_element_endmark) { // insert a repeat before the '(' matching the last ')': insert_point = this->m_paren_start; } else if((this->m_last_state->type == syntax_element_literal) && (static_cast<re_literal*>(this->m_last_state)->length > 1)) { // the last state was a literal with more than one character, split it in two: re_literal* lit = static_cast<re_literal*>(this->m_last_state); charT c = (static_cast<charT*>(static_cast<void*>(lit+1)))[lit->length - 1]; --(lit->length); // now append new state: lit = static_cast<re_literal*>(this->append_state(syntax_element_literal, sizeof(re_literal) + sizeof(charT))); lit->length = 1; (static_cast<charT*>(static_cast<void*>(lit+1)))[0] = c; insert_point = this->getoffset(this->m_last_state); } else { // repeat the last state whatever it was, need to add some error checking here: switch(this->m_last_state->type) { case syntax_element_start_line: case syntax_element_end_line: case syntax_element_word_boundary: case syntax_element_within_word: case syntax_element_word_start: case syntax_element_word_end: case syntax_element_buffer_start: case syntax_element_buffer_end: case syntax_element_alt: case syntax_element_soft_buffer_end: case syntax_element_restart_continue: case syntax_element_jump: case syntax_element_startmark: case syntax_element_backstep: // can't legally repeat any of the above: fail(regex_constants::error_badrepeat, m_position - m_base); return false; default: // do nothing... break; } insert_point = this->getoffset(this->m_last_state); } // // OK we now know what to repeat, so insert the repeat around it: // re_repeat* rep = static_cast<re_repeat*>(this->insert_state(insert_point, syntax_element_rep, re_repeater_size)); rep->min = low; rep->max = high; rep->greedy = greedy; rep->leading = false; // store our repeater position for later: std::ptrdiff_t rep_off = this->getoffset(rep); // and append a back jump to the repeat: re_jump* jmp = static_cast<re_jump*>(this->append_state(syntax_element_jump, sizeof(re_jump))); jmp->alt.i = rep_off - this->getoffset(jmp); this->m_pdata->m_data.align(); // now fill in the alt jump for the repeat: rep = static_cast<re_repeat*>(this->getaddress(rep_off)); rep->alt.i = this->m_pdata->m_data.size() - rep_off; // // If the repeat is pocessive then bracket the repeat with a (?>...) // independent sub-expression construct: // if(pocessive) { re_brace* pb = static_cast<re_brace*>(this->insert_state(insert_point, syntax_element_startmark, sizeof(re_brace))); pb->index = -3; pb->icase = this->flags() & regbase::icase; jmp = static_cast<re_jump*>(this->insert_state(insert_point + sizeof(re_brace), syntax_element_jump, sizeof(re_jump))); this->m_pdata->m_data.align(); jmp->alt.i = this->m_pdata->m_data.size() - this->getoffset(jmp); pb = static_cast<re_brace*>(this->append_state(syntax_element_endmark, sizeof(re_brace))); pb->index = -3; pb->icase = this->flags() & regbase::icase; } return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_repeat_range(bool isbasic) { static const char* incomplete_message = "Missing } in quantified repetition."; // // parse a repeat-range: // std::size_t min, max; int v; // skip whitespace: while((m_position != m_end) && this->m_traits.isctype(*m_position, this->m_mask_space)) ++m_position; // fail if at end: if(this->m_position == this->m_end) { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } // get min: v = this->m_traits.toi(m_position, m_end, 10); // skip whitespace: while((m_position != m_end) && this->m_traits.isctype(*m_position, this->m_mask_space)) ++m_position; if(v < 0) { fail(regex_constants::error_badbrace, this->m_position - this->m_base); return false; } else if(this->m_position == this->m_end) { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } min = v; // see if we have a comma: if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_comma) { // move on and error check: ++m_position; // skip whitespace: while((m_position != m_end) && this->m_traits.isctype(*m_position, this->m_mask_space)) ++m_position; if(this->m_position == this->m_end) { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } // get the value if any: v = this->m_traits.toi(m_position, m_end, 10); max = (v >= 0) ? v : (std::numeric_limits<std::size_t>::max)(); } else { // no comma, max = min: max = min; } // skip whitespace: while((m_position != m_end) && this->m_traits.isctype(*m_position, this->m_mask_space)) ++m_position; // OK now check trailing }: if(this->m_position == this->m_end) { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } if(isbasic) { if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_escape) { ++m_position; if(this->m_position == this->m_end) { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } } else { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } } if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_brace) ++m_position; else { fail(regex_constants::error_brace, this->m_position - this->m_base, incomplete_message); return false; } // // finally go and add the repeat, unless error: // if(min > max) { // Backtrack to error location: m_position -= 2; while(this->m_traits.isctype(*m_position, this->m_word_mask)) --m_position; ++m_position; fail(regex_constants::error_badbrace, m_position - m_base); return false; } return parse_repeat(min, max); } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_alt() { // // error check: if there have been no previous states, // or if the last state was a '(' then error: // if( ((this->m_last_state == 0) || (this->m_last_state->type == syntax_element_startmark)) && !( ((this->flags() & regbase::main_option_type) == regbase::perl_syntax_group) && ((this->flags() & regbase::no_empty_expressions) == 0) ) ) { fail(regex_constants::error_empty, this->m_position - this->m_base, "A regular expression can start with the alternation operator |."); return false; } // // Reset mark count if required: // if(m_max_mark < m_mark_count) m_max_mark = m_mark_count; if(m_mark_reset >= 0) m_mark_count = m_mark_reset; ++m_position; // // we need to append a trailing jump: // re_syntax_base* pj = this->append_state(re_detail::syntax_element_jump, sizeof(re_jump)); std::ptrdiff_t jump_offset = this->getoffset(pj); // // now insert the alternative: // re_alt* palt = static_cast<re_alt*>(this->insert_state(this->m_alt_insert_point, syntax_element_alt, re_alt_size)); jump_offset += re_alt_size; this->m_pdata->m_data.align(); palt->alt.i = this->m_pdata->m_data.size() - this->getoffset(palt); // // update m_alt_insert_point so that the next alternate gets // inserted at the start of the second of the two we've just created: // this->m_alt_insert_point = this->m_pdata->m_data.size(); // // the start of this alternative must have a case changes state // if the current block has messed around with case changes: // if(m_has_case_change) { static_cast<re_case*>( this->append_state(syntax_element_toggle_case, sizeof(re_case)) )->icase = this->m_icase; } // // push the alternative onto our stack, a recursive // implementation here is easier to understand (and faster // as it happens), but causes all kinds of stack overflow problems // on programs with small stacks (COM+). // m_alt_jumps.push_back(jump_offset); return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_set() { static const char* incomplete_message = "Character set declaration starting with [ terminated prematurely - either no ] was found or the set had no content."; ++m_position; if(m_position == m_end) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } basic_char_set<charT, traits> char_set; const charT* base = m_position; // where the '[' was const charT* item_base = m_position; // where the '[' or '^' was while(m_position != m_end) { switch(this->m_traits.syntax_type(*m_position)) { case regex_constants::syntax_caret: if(m_position == base) { char_set.negate(); ++m_position; item_base = m_position; } else parse_set_literal(char_set); break; case regex_constants::syntax_close_set: if(m_position == item_base) { parse_set_literal(char_set); break; } else { ++m_position; if(0 == this->append_set(char_set)) { fail(regex_constants::error_ctype, m_position - m_base); return false; } } return true; case regex_constants::syntax_open_set: if(parse_inner_set(char_set)) break; return true; case regex_constants::syntax_escape: { // // look ahead and see if this is a character class shortcut // \d \w \s etc... // ++m_position; if(this->m_traits.escape_syntax_type(*m_position) == regex_constants::escape_type_class) { char_class_type m = this->m_traits.lookup_classname(m_position, m_position+1); if(m != 0) { char_set.add_class(m); ++m_position; break; } } else if(this->m_traits.escape_syntax_type(*m_position) == regex_constants::escape_type_not_class) { // negated character class: char_class_type m = this->m_traits.lookup_classname(m_position, m_position+1); if(m != 0) { char_set.add_negated_class(m); ++m_position; break; } } // not a character class, just a regular escape: --m_position; parse_set_literal(char_set); break; } default: parse_set_literal(char_set); break; } } return m_position != m_end; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_inner_set(basic_char_set<charT, traits>& char_set) { static const char* incomplete_message = "Character class declaration starting with [ terminated prematurely - either no ] was found or the set had no content."; // // we have either a character class [:name:] // a collating element [.name.] // or an equivalence class [=name=] // if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } switch(this->m_traits.syntax_type(*m_position)) { case regex_constants::syntax_dot: // // a collating element is treated as a literal: // --m_position; parse_set_literal(char_set); return true; case regex_constants::syntax_colon: { // check that character classes are actually enabled: if((this->flags() & (regbase::main_option_type | regbase::no_char_classes)) == (regbase::basic_syntax_group | regbase::no_char_classes)) { --m_position; parse_set_literal(char_set); return true; } // skip the ':' if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } const charT* name_first = m_position; // skip at least one character, then find the matching ':]' if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_colon)) ++m_position; const charT* name_last = m_position; if(m_end == m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } if((m_end == ++m_position) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_set)) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } // // check for negated class: // bool negated = false; if(this->m_traits.syntax_type(*name_first) == regex_constants::syntax_caret) { ++name_first; negated = true; } typedef typename traits::char_class_type mask_type; mask_type m = this->m_traits.lookup_classname(name_first, name_last); if(m == 0) { if(char_set.empty() && (name_last - name_first == 1)) { // maybe a special case: ++m_position; if( (m_position != m_end) && (this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_set)) { if(this->m_traits.escape_syntax_type(*name_first) == regex_constants::escape_type_left_word) { ++m_position; this->append_state(syntax_element_word_start); return false; } if(this->m_traits.escape_syntax_type(*name_first) == regex_constants::escape_type_right_word) { ++m_position; this->append_state(syntax_element_word_end); return false; } } } fail(regex_constants::error_ctype, name_first - m_base); return false; } if(negated == false) char_set.add_class(m); else char_set.add_negated_class(m); ++m_position; break; } case regex_constants::syntax_equal: { // skip the '=' if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } const charT* name_first = m_position; // skip at least one character, then find the matching '=]' if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_equal)) ++m_position; const charT* name_last = m_position; if(m_end == m_position) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } if((m_end == ++m_position) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_set)) { fail(regex_constants::error_brack, m_position - m_base, incomplete_message); return false; } string_type m = this->m_traits.lookup_collatename(name_first, name_last); if((0 == m.size()) || (m.size() > 2)) { fail(regex_constants::error_collate, name_first - m_base); return false; } digraph<charT> d; d.first = m[0]; if(m.size() > 1) d.second = m[1]; else d.second = 0; char_set.add_equivalent(d); ++m_position; break; } default: --m_position; parse_set_literal(char_set); break; } return true; } template <class charT, class traits> void basic_regex_parser<charT, traits>::parse_set_literal(basic_char_set<charT, traits>& char_set) { digraph<charT> start_range(get_next_set_literal(char_set)); if(m_end == m_position) { fail(regex_constants::error_brack, m_position - m_base); return; } if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_dash) { // we have a range: if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base); return; } if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_set) { digraph<charT> end_range = get_next_set_literal(char_set); char_set.add_range(start_range, end_range); if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_dash) { if(m_end == ++m_position) { fail(regex_constants::error_brack, m_position - m_base); return; } if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_set) { // trailing - : --m_position; return; } fail(regex_constants::error_range, m_position - m_base); return; } return; } --m_position; } char_set.add_single(start_range); } template <class charT, class traits> digraph<charT> basic_regex_parser<charT, traits>::get_next_set_literal(basic_char_set<charT, traits>& char_set) { digraph<charT> result; switch(this->m_traits.syntax_type(*m_position)) { case regex_constants::syntax_dash: if(!char_set.empty()) { // see if we are at the end of the set: if((++m_position == m_end) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_set)) { fail(regex_constants::error_range, m_position - m_base); return result; } --m_position; } result.first = *m_position++; return result; case regex_constants::syntax_escape: // check to see if escapes are supported first: if(this->flags() & regex_constants::no_escape_in_lists) { result = *m_position++; break; } ++m_position; result = unescape_character(); break; case regex_constants::syntax_open_set: { if(m_end == ++m_position) { fail(regex_constants::error_collate, m_position - m_base); return result; } if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_dot) { --m_position; result.first = *m_position; ++m_position; return result; } if(m_end == ++m_position) { fail(regex_constants::error_collate, m_position - m_base); return result; } const charT* name_first = m_position; // skip at least one character, then find the matching ':]' if(m_end == ++m_position) { fail(regex_constants::error_collate, name_first - m_base); return result; } while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_dot)) ++m_position; const charT* name_last = m_position; if(m_end == m_position) { fail(regex_constants::error_collate, name_first - m_base); return result; } if((m_end == ++m_position) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_set)) { fail(regex_constants::error_collate, name_first - m_base); return result; } ++m_position; string_type s = this->m_traits.lookup_collatename(name_first, name_last); if(s.empty() || (s.size() > 2)) { fail(regex_constants::error_collate, name_first - m_base); return result; } result.first = s[0]; if(s.size() > 1) result.second = s[1]; else result.second = 0; return result; } default: result = *m_position++; } return result; } // // does a value fit in the specified charT type? // template <class charT> bool valid_value(charT, int v, const mpl::true_&) { return (v >> (sizeof(charT) * CHAR_BIT)) == 0; } template <class charT> bool valid_value(charT, int, const mpl::false_&) { return true; // v will alsways fit in a charT } template <class charT> bool valid_value(charT c, int v) { return valid_value(c, v, mpl::bool_<(sizeof(charT) < sizeof(int))>()); } template <class charT, class traits> charT basic_regex_parser<charT, traits>::unescape_character() { #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable:4127) #endif charT result(0); if(m_position == m_end) { fail(regex_constants::error_escape, m_position - m_base, "Escape sequence terminated prematurely."); return false; } switch(this->m_traits.escape_syntax_type(*m_position)) { case regex_constants::escape_type_control_a: result = charT('\a'); break; case regex_constants::escape_type_e: result = charT(27); break; case regex_constants::escape_type_control_f: result = charT('\f'); break; case regex_constants::escape_type_control_n: result = charT('\n'); break; case regex_constants::escape_type_control_r: result = charT('\r'); break; case regex_constants::escape_type_control_t: result = charT('\t'); break; case regex_constants::escape_type_control_v: result = charT('\v'); break; case regex_constants::escape_type_word_assert: result = charT('\b'); break; case regex_constants::escape_type_ascii_control: ++m_position; if(m_position == m_end) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base, "ASCII escape sequence terminated prematurely."); return result; } result = static_cast<charT>(*m_position % 32); break; case regex_constants::escape_type_hex: ++m_position; if(m_position == m_end) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base, "Hexadecimal escape sequence terminated prematurely."); return result; } // maybe have \x{ddd} if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_open_brace) { ++m_position; if(m_position == m_end) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base, "Missing } in hexadecimal escape sequence."); return result; } int i = this->m_traits.toi(m_position, m_end, 16); if((m_position == m_end) || (i < 0) || ((std::numeric_limits<charT>::is_specialized) && (i > (int)(std::numeric_limits<charT>::max)())) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_brace)) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_badbrace, m_position - m_base, "Hexadecimal escape sequence was invalid."); return result; } ++m_position; result = charT(i); } else { std::ptrdiff_t len = (std::min)(static_cast<std::ptrdiff_t>(2), static_cast<std::ptrdiff_t>(m_end - m_position)); int i = this->m_traits.toi(m_position, m_position + len, 16); if((i < 0) || !valid_value(charT(0), i)) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base, "Escape sequence did not encode a valid character."); return result; } result = charT(i); } return result; case regex_constants::syntax_digit: { // an octal escape sequence, the first character must be a zero // followed by up to 3 octal digits: std::ptrdiff_t len = (std::min)(::boost::re_detail::distance(m_position, m_end), static_cast<std::ptrdiff_t>(4)); const charT* bp = m_position; int val = this->m_traits.toi(bp, bp + 1, 8); if(val != 0) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; // Oops not an octal escape after all: fail(regex_constants::error_escape, m_position - m_base, "Invalid octal escape sequence."); return result; } val = this->m_traits.toi(m_position, m_position + len, 8); if(val < 0) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base, "Octal escape sequence is invalid."); return result; } return static_cast<charT>(val); } case regex_constants::escape_type_named_char: { ++m_position; if(m_position == m_end) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base); return false; } // maybe have \N{name} if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_open_brace) { const charT* base = m_position; // skip forward until we find enclosing brace: while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_brace)) ++m_position; if(m_position == m_end) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base); return false; } string_type s = this->m_traits.lookup_collatename(++base, m_position++); if(s.empty()) { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_collate, m_position - m_base); return false; } if(s.size() == 1) { return s[0]; } } // fall through is a failure: // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base); return false; } default: result = *m_position; break; } ++m_position; return result; #ifdef BOOST_MSVC #pragma warning(pop) #endif } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_backref() { BOOST_ASSERT(m_position != m_end); const charT* pc = m_position; int i = this->m_traits.toi(pc, pc + 1, 10); if((i == 0) || (((this->flags() & regbase::main_option_type) == regbase::perl_syntax_group) && (this->flags() & regbase::no_bk_refs))) { // not a backref at all but an octal escape sequence: charT c = unescape_character(); this->append_literal(c); } else if((i > 0) && (this->m_backrefs & (1u << (i-1)))) { m_position = pc; re_brace* pb = static_cast<re_brace*>(this->append_state(syntax_element_backref, sizeof(re_brace))); pb->index = i; pb->icase = this->flags() & regbase::icase; } else { // Rewind to start of escape: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_backref, m_position - m_base); return false; } return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_QE() { #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable:4127) #endif // // parse a \Q...\E sequence: // ++m_position; // skip the Q const charT* start = m_position; const charT* end; do { while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape)) ++m_position; if(m_position == m_end) { // a \Q...\E sequence may terminate with the end of the expression: end = m_position; break; } if(++m_position == m_end) // skip the escape { fail(regex_constants::error_escape, m_position - m_base, "Unterminated \\Q...\\E sequence."); return false; } // check to see if it's a \E: if(this->m_traits.escape_syntax_type(*m_position) == regex_constants::escape_type_E) { ++m_position; end = m_position - 2; break; } // otherwise go round again: }while(true); // // now add all the character between the two escapes as literals: // while(start != end) { this->append_literal(*start); ++start; } return true; #ifdef BOOST_MSVC #pragma warning(pop) #endif } template <class charT, class traits> bool basic_regex_parser<charT, traits>::parse_perl_extension() { if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } // // treat comments as a special case, as these // are the only ones that don't start with a leading // startmark state: // if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_hash) { while((m_position != m_end) && (this->m_traits.syntax_type(*m_position++) != regex_constants::syntax_close_mark)) {} return true; } // // backup some state, and prepare the way: // int markid = 0; std::ptrdiff_t jump_offset = 0; re_brace* pb = static_cast<re_brace*>(this->append_state(syntax_element_startmark, sizeof(re_brace))); pb->icase = this->flags() & regbase::icase; std::ptrdiff_t last_paren_start = this->getoffset(pb); // back up insertion point for alternations, and set new point: std::ptrdiff_t last_alt_point = m_alt_insert_point; this->m_pdata->m_data.align(); m_alt_insert_point = this->m_pdata->m_data.size(); std::ptrdiff_t expected_alt_point = m_alt_insert_point; bool restore_flags = true; regex_constants::syntax_option_type old_flags = this->flags(); bool old_case_change = m_has_case_change; m_has_case_change = false; charT name_delim; int mark_reset = m_mark_reset; m_mark_reset = -1; int v; // // select the actual extension used: // switch(this->m_traits.syntax_type(*m_position)) { case regex_constants::syntax_or: m_mark_reset = m_mark_count; // fall through: case regex_constants::syntax_colon: // // a non-capturing mark: // pb->index = markid = 0; ++m_position; break; case regex_constants::syntax_digit: { // // a recursive subexpression: // v = this->m_traits.toi(m_position, m_end, 10); if((v < 0) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base, "The recursive sub-expression refers to an invalid marking group, or is unterminated."); return false; } insert_recursion: pb->index = markid = 0; re_recurse* pr = static_cast<re_recurse*>(this->append_state(syntax_element_recurse, sizeof(re_recurse))); pr->alt.i = v; pr->state_id = 0; static_cast<re_case*>( this->append_state(syntax_element_toggle_case, sizeof(re_case)) )->icase = this->flags() & regbase::icase; break; } case regex_constants::syntax_plus: // // A forward-relative recursive subexpression: // ++m_position; v = this->m_traits.toi(m_position, m_end, 10); if((v <= 0) || (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base, "An invalid or unterminated recursive sub-expression."); return false; } v += m_mark_count; goto insert_recursion; case regex_constants::syntax_dash: // // Possibly a backward-relative recursive subexpression: // ++m_position; v = this->m_traits.toi(m_position, m_end, 10); if(v <= 0) { --m_position; // Oops not a relative recursion at all, but a (?-imsx) group: goto option_group_jump; } v = m_mark_count + 1 - v; if(v <= 0) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base, "An invalid or unterminated recursive sub-expression."); return false; } goto insert_recursion; case regex_constants::syntax_equal: pb->index = markid = -1; ++m_position; jump_offset = this->getoffset(this->append_state(syntax_element_jump, sizeof(re_jump))); this->m_pdata->m_data.align(); m_alt_insert_point = this->m_pdata->m_data.size(); break; case regex_constants::syntax_not: pb->index = markid = -2; ++m_position; jump_offset = this->getoffset(this->append_state(syntax_element_jump, sizeof(re_jump))); this->m_pdata->m_data.align(); m_alt_insert_point = this->m_pdata->m_data.size(); break; case regex_constants::escape_type_left_word: { // a lookbehind assertion: if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } regex_constants::syntax_type t = this->m_traits.syntax_type(*m_position); if(t == regex_constants::syntax_not) pb->index = markid = -2; else if(t == regex_constants::syntax_equal) pb->index = markid = -1; else { // Probably a named capture which also starts (?< : name_delim = '>'; --m_position; goto named_capture_jump; } ++m_position; jump_offset = this->getoffset(this->append_state(syntax_element_jump, sizeof(re_jump))); this->append_state(syntax_element_backstep, sizeof(re_brace)); this->m_pdata->m_data.align(); m_alt_insert_point = this->m_pdata->m_data.size(); break; } case regex_constants::escape_type_right_word: // // an independent sub-expression: // pb->index = markid = -3; ++m_position; jump_offset = this->getoffset(this->append_state(syntax_element_jump, sizeof(re_jump))); this->m_pdata->m_data.align(); m_alt_insert_point = this->m_pdata->m_data.size(); break; case regex_constants::syntax_open_mark: { // a conditional expression: pb->index = markid = -4; if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } v = this->m_traits.toi(m_position, m_end, 10); if(*m_position == charT('R')) { if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(*m_position == charT('&')) { const charT* base = ++m_position; while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark)) ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } v = -static_cast<int>(hash_value_from_capture_name(base, m_position)); } else { v = -this->m_traits.toi(m_position, m_end, 10); } re_brace* br = static_cast<re_brace*>(this->append_state(syntax_element_assert_backref, sizeof(re_brace))); br->index = v < 0 ? (v - 1) : 0; if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } } else if((*m_position == charT('\'')) || (*m_position == charT('<'))) { const charT* base = ++m_position; while((m_position != m_end) && (*m_position != charT('>')) && (*m_position != charT('\''))) ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } v = static_cast<int>(hash_value_from_capture_name(base, m_position)); re_brace* br = static_cast<re_brace*>(this->append_state(syntax_element_assert_backref, sizeof(re_brace))); br->index = v; if(((*m_position != charT('>')) && (*m_position != charT('\''))) || (++m_position == m_end)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base, "Unterminated named capture."); return false; } if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } } else if(*m_position == charT('D')) { const char* def = "DEFINE"; while(*def && (m_position != m_end) && (*m_position == charT(*def))) ++m_position, ++def; if((m_position == m_end) || *def) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } re_brace* br = static_cast<re_brace*>(this->append_state(syntax_element_assert_backref, sizeof(re_brace))); br->index = 9999; // special magic value! if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } } else if(v > 0) { re_brace* br = static_cast<re_brace*>(this->append_state(syntax_element_assert_backref, sizeof(re_brace))); br->index = v; if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } } else { // verify that we have a lookahead or lookbehind assert: if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_question) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(this->m_traits.syntax_type(*m_position) == regex_constants::escape_type_left_word) { if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if((this->m_traits.syntax_type(*m_position) != regex_constants::syntax_equal) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_not)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } m_position -= 3; } else { if((this->m_traits.syntax_type(*m_position) != regex_constants::syntax_equal) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_not)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } m_position -= 2; } } break; } case regex_constants::syntax_close_mark: // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; case regex_constants::escape_type_end_buffer: { name_delim = *m_position; named_capture_jump: markid = 0; if(0 == (this->flags() & regbase::nosubs)) { markid = ++m_mark_count; #ifndef BOOST_NO_STD_DISTANCE if(this->flags() & regbase::save_subexpression_location) this->m_pdata->m_subs.push_back(std::pair<std::size_t, std::size_t>(std::distance(m_base, m_position) - 2, 0)); #else if(this->flags() & regbase::save_subexpression_location) this->m_pdata->m_subs.push_back(std::pair<std::size_t, std::size_t>((m_position - m_base) - 2, 0)); #endif } pb->index = markid; const charT* base = ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } while((m_position != m_end) && (*m_position != name_delim)) ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } this->m_pdata->set_name(base, m_position, markid); ++m_position; break; } default: if(*m_position == charT('R')) { ++m_position; v = 0; if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } goto insert_recursion; } if(*m_position == charT('&')) { ++m_position; const charT* base = m_position; while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark)) ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } v = static_cast<int>(hash_value_from_capture_name(base, m_position)); goto insert_recursion; } if(*m_position == charT('P')) { ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } if(*m_position == charT('>')) { ++m_position; const charT* base = m_position; while((m_position != m_end) && (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark)) ++m_position; if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } v = static_cast<int>(hash_value_from_capture_name(base, m_position)); goto insert_recursion; } } // // lets assume that we have a (?imsx) group and try and parse it: // option_group_jump: regex_constants::syntax_option_type opts = parse_options(); if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } // make a note of whether we have a case change: m_has_case_change = ((opts & regbase::icase) != (this->flags() & regbase::icase)); pb->index = markid = 0; if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_mark) { // update flags and carry on as normal: this->flags(opts); restore_flags = false; old_case_change |= m_has_case_change; // defer end of scope by one ')' } else if(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_colon) { // update flags and carry on until the matching ')' is found: this->flags(opts); ++m_position; } else { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base); return false; } // finally append a case change state if we need it: if(m_has_case_change) { static_cast<re_case*>( this->append_state(syntax_element_toggle_case, sizeof(re_case)) )->icase = opts & regbase::icase; } } // // now recursively add more states, this will terminate when we get to a // matching ')' : // parse_all(); // // Unwind alternatives: // if(0 == unwind_alts(last_paren_start)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base, "Invalid alternation operators within (?...) block."); return false; } // // we either have a ')' or we have run out of characters prematurely: // if(m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; this->fail(regex_constants::error_paren, ::boost::re_detail::distance(m_base, m_end)); return false; } BOOST_ASSERT(this->m_traits.syntax_type(*m_position) == regex_constants::syntax_close_mark); ++m_position; // // restore the flags: // if(restore_flags) { // append a case change state if we need it: if(m_has_case_change) { static_cast<re_case*>( this->append_state(syntax_element_toggle_case, sizeof(re_case)) )->icase = old_flags & regbase::icase; } this->flags(old_flags); } // // set up the jump pointer if we have one: // if(jump_offset) { this->m_pdata->m_data.align(); re_jump* jmp = static_cast<re_jump*>(this->getaddress(jump_offset)); jmp->alt.i = this->m_pdata->m_data.size() - this->getoffset(jmp); if(this->m_last_state == jmp) { // Oops... we didn't have anything inside the assertion: // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_perl_extension, m_position - m_base, "Invalid or empty zero width assertion."); return false; } } // // verify that if this is conditional expression, that we do have // an alternative, if not add one: // if(markid == -4) { re_syntax_base* b = this->getaddress(expected_alt_point); // Make sure we have exactly one alternative following this state: if(b->type != syntax_element_alt) { re_alt* alt = static_cast<re_alt*>(this->insert_state(expected_alt_point, syntax_element_alt, sizeof(re_alt))); alt->alt.i = this->m_pdata->m_data.size() - this->getoffset(alt); } else if(this->getaddress(static_cast<re_alt*>(b)->alt.i, b)->type == syntax_element_alt) { // Can't have seen more than one alternative: // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_bad_pattern, m_position - m_base, "More than one alternation operator | was encountered inside a conditional expression."); return false; } else { // We must *not* have seen an alternative inside a (DEFINE) block: b = this->getaddress(b->next.i, b); if((b->type == syntax_element_assert_backref) && (static_cast<re_brace*>(b)->index == 9999)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_bad_pattern, m_position - m_base, "Alternation operators are not allowed inside a DEFINE block."); return false; } } // check for invalid repetition of next state: b = this->getaddress(expected_alt_point); b = this->getaddress(static_cast<re_alt*>(b)->next.i, b); if((b->type != syntax_element_assert_backref) && (b->type != syntax_element_startmark)) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_badrepeat, m_position - m_base, "A repetition operator cannot be applied to a zero-width assertion."); return false; } } // // append closing parenthesis state: // pb = static_cast<re_brace*>(this->append_state(syntax_element_endmark, sizeof(re_brace))); pb->index = markid; pb->icase = this->flags() & regbase::icase; this->m_paren_start = last_paren_start; // // restore the alternate insertion point: // this->m_alt_insert_point = last_alt_point; // // and the case change data: // m_has_case_change = old_case_change; // // And the mark_reset data: // if(m_max_mark > m_mark_count) { m_mark_count = m_max_mark; } m_mark_reset = mark_reset; if(markid > 0) { #ifndef BOOST_NO_STD_DISTANCE if(this->flags() & regbase::save_subexpression_location) this->m_pdata->m_subs.at(markid - 1).second = std::distance(m_base, m_position) - 1; #else if(this->flags() & regbase::save_subexpression_location) this->m_pdata->m_subs.at(markid - 1).second = (m_position - m_base) - 1; #endif // // allow backrefs to this mark: // if((markid > 0) && (markid < (int)(sizeof(unsigned) * CHAR_BIT))) this->m_backrefs |= 1u << (markid - 1); } return true; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::add_emacs_code(bool negate) { // // parses an emacs style \sx or \Sx construct. // if(++m_position == m_end) { // Rewind to start of sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_escape) --m_position; fail(regex_constants::error_escape, m_position - m_base); return false; } basic_char_set<charT, traits> char_set; if(negate) char_set.negate(); static const charT s_punct[5] = { 'p', 'u', 'n', 'c', 't', }; switch(*m_position) { case 's': case ' ': char_set.add_class(this->m_mask_space); break; case 'w': char_set.add_class(this->m_word_mask); break; case '_': char_set.add_single(digraph<charT>(charT('$'))); char_set.add_single(digraph<charT>(charT('&'))); char_set.add_single(digraph<charT>(charT('*'))); char_set.add_single(digraph<charT>(charT('+'))); char_set.add_single(digraph<charT>(charT('-'))); char_set.add_single(digraph<charT>(charT('_'))); char_set.add_single(digraph<charT>(charT('<'))); char_set.add_single(digraph<charT>(charT('>'))); break; case '.': char_set.add_class(this->m_traits.lookup_classname(s_punct, s_punct+5)); break; case '(': char_set.add_single(digraph<charT>(charT('('))); char_set.add_single(digraph<charT>(charT('['))); char_set.add_single(digraph<charT>(charT('{'))); break; case ')': char_set.add_single(digraph<charT>(charT(')'))); char_set.add_single(digraph<charT>(charT(']'))); char_set.add_single(digraph<charT>(charT('}'))); break; case '"': char_set.add_single(digraph<charT>(charT('"'))); char_set.add_single(digraph<charT>(charT('\''))); char_set.add_single(digraph<charT>(charT('`'))); break; case '\'': char_set.add_single(digraph<charT>(charT('\''))); char_set.add_single(digraph<charT>(charT(','))); char_set.add_single(digraph<charT>(charT('#'))); break; case '<': char_set.add_single(digraph<charT>(charT(';'))); break; case '>': char_set.add_single(digraph<charT>(charT('\n'))); char_set.add_single(digraph<charT>(charT('\f'))); break; default: fail(regex_constants::error_ctype, m_position - m_base); return false; } if(0 == this->append_set(char_set)) { fail(regex_constants::error_ctype, m_position - m_base); return false; } ++m_position; return true; } template <class charT, class traits> regex_constants::syntax_option_type basic_regex_parser<charT, traits>::parse_options() { // we have a (?imsx-imsx) group, convert it into a set of flags: regex_constants::syntax_option_type f = this->flags(); bool breakout = false; do { switch(*m_position) { case 's': f |= regex_constants::mod_s; f &= ~regex_constants::no_mod_s; break; case 'm': f &= ~regex_constants::no_mod_m; break; case 'i': f |= regex_constants::icase; break; case 'x': f |= regex_constants::mod_x; break; default: breakout = true; continue; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_paren, m_position - m_base); return false; } } while(!breakout); if(*m_position == static_cast<charT>('-')) { if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_paren, m_position - m_base); return false; } do { switch(*m_position) { case 's': f &= ~regex_constants::mod_s; f |= regex_constants::no_mod_s; break; case 'm': f |= regex_constants::no_mod_m; break; case 'i': f &= ~regex_constants::icase; break; case 'x': f &= ~regex_constants::mod_x; break; default: breakout = true; continue; } if(++m_position == m_end) { // Rewind to start of (? sequence: --m_position; while(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_open_mark) --m_position; fail(regex_constants::error_paren, m_position - m_base); return false; } } while(!breakout); } return f; } template <class charT, class traits> bool basic_regex_parser<charT, traits>::unwind_alts(std::ptrdiff_t last_paren_start) { // // If we didn't actually add any states after the last // alternative then that's an error: // if((this->m_alt_insert_point == static_cast<std::ptrdiff_t>(this->m_pdata->m_data.size())) && m_alt_jumps.size() && (m_alt_jumps.back() > last_paren_start) && !( ((this->flags() & regbase::main_option_type) == regbase::perl_syntax_group) && ((this->flags() & regbase::no_empty_expressions) == 0) ) ) { fail(regex_constants::error_empty, this->m_position - this->m_base, "Can't terminate a sub-expression with an alternation operator |."); return false; } // // Fix up our alternatives: // while(m_alt_jumps.size() && (m_alt_jumps.back() > last_paren_start)) { // // fix up the jump to point to the end of the states // that we've just added: // std::ptrdiff_t jump_offset = m_alt_jumps.back(); m_alt_jumps.pop_back(); this->m_pdata->m_data.align(); re_jump* jmp = static_cast<re_jump*>(this->getaddress(jump_offset)); BOOST_ASSERT(jmp->type == syntax_element_jump); jmp->alt.i = this->m_pdata->m_data.size() - jump_offset; } return true; } #ifdef BOOST_MSVC #pragma warning(pop) #endif } // namespace re_detail } // namespace boost #ifdef BOOST_MSVC #pragma warning(push) #pragma warning(disable: 4103) #endif #ifdef BOOST_HAS_ABI_HEADERS # include BOOST_ABI_SUFFIX #endif #ifdef BOOST_MSVC #pragma warning(pop) #endif #endif