| // generate_re2c.hpp | |
| // Copyright (c) 2009 Ben Hanson (http://www.benhanson.net/) | |
| // | |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying | |
| // file licence_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) | |
| #ifndef LEXERTL_GENERATE_RE2C_HPP | |
| #define LEXERTL_GENERATE_RE2C_HPP | |
| #include "char_traits.hpp" | |
| #include "consts.hpp" | |
| #include "internals.hpp" | |
| #include <iostream> | |
| #include "runtime_error.hpp" | |
| #include "size_t.hpp" | |
| #include "state_machine.hpp" | |
| #include <vector> | |
| namespace boost | |
| { | |
| namespace lexer | |
| { | |
| // check whether state0_0 is referenced from any of the other states | |
| template <typename Char> | |
| bool need_label0_0(boost::lexer::basic_state_machine<Char> const &sm_) | |
| { | |
| typedef typename boost::lexer::basic_state_machine<Char>::iterator | |
| iterator_type; | |
| iterator_type iter_ = sm_.begin(); | |
| std::size_t states_ = iter_->states; | |
| for (std::size_t state_ = 0; state_ < states_; ++state_) | |
| { | |
| if (0 == iter_->bol_index || 0 == iter_->eol_index) | |
| { | |
| return true; | |
| } | |
| std::size_t const transitions_ = iter_->transitions; | |
| for (std::size_t t_ = 0; t_ < transitions_; ++t_) | |
| { | |
| if (0 == iter_->goto_state) | |
| { | |
| return true; | |
| } | |
| ++iter_; | |
| } | |
| if (transitions_ == 0) ++iter_; | |
| } | |
| return false; | |
| } | |
| template<typename CharT> | |
| void generate_re2c (const basic_state_machine<CharT> &state_machine_, | |
| std::ostream &os_, const bool use_pointers_ = false, | |
| const bool skip_unknown_ = true, const bool optimise_parameters_ = true, | |
| const char *name_ = "next_token") | |
| { | |
| typedef typename boost::lexer::basic_string_token<CharT> string_token; | |
| const detail::internals &sm_ = state_machine_.data (); | |
| if (sm_._lookup->size () == 0) | |
| { | |
| throw runtime_error ("Cannot generate code from an empty " | |
| "state machine"); | |
| } | |
| std::string upper_name_ (__DATE__); | |
| const std::size_t lookups_ = sm_._lookup->front ()->size (); | |
| typename boost::lexer::basic_state_machine<CharT>::iterator iter_ = | |
| state_machine_.begin(); | |
| typename boost::lexer::basic_state_machine<CharT>::iterator end_ = | |
| state_machine_.end(); | |
| const std::size_t dfas_ = sm_._dfa->size (); | |
| std::string::size_type pos_ = upper_name_.find (' '); | |
| const char *iterator_ = 0; | |
| if (use_pointers_) | |
| { | |
| if (lookups_ == 256) | |
| { | |
| iterator_ = "const char *"; | |
| } | |
| else | |
| { | |
| iterator_ = "const wchar_t *"; | |
| } | |
| } | |
| else | |
| { | |
| iterator_ = "Iterator &"; | |
| } | |
| while (pos_ != std::string::npos) | |
| { | |
| upper_name_.replace (pos_, 1, "_"); | |
| pos_ = upper_name_.find (' ', pos_); | |
| } | |
| upper_name_ += '_'; | |
| upper_name_ += __TIME__; | |
| pos_ = upper_name_.find (':'); | |
| while (pos_ != std::string::npos) | |
| { | |
| upper_name_.erase (pos_, 1); | |
| pos_ = upper_name_.find (':', pos_); | |
| } | |
| upper_name_ = '_' + upper_name_; | |
| upper_name_ = name_ + upper_name_; | |
| std::transform (upper_name_.begin (), upper_name_.end (), | |
| upper_name_.begin (), ::toupper); | |
| os_ << "#ifndef " << upper_name_ + '\n'; | |
| os_ << "#define " << upper_name_ + '\n'; | |
| os_ << "// Copyright (c) 2008-2009 Ben Hanson\n"; | |
| os_ << "//\n"; | |
| os_ << "// Distributed under the Boost Software License, " | |
| "Version 1.0. (See accompanying\n"; | |
| os_ << "// file licence_1_0.txt or copy at " | |
| "http://www.boost.org/LICENSE_1_0.txt)\n\n"; | |
| os_ << "// Auto-generated by boost::lexer\n"; | |
| os_ << "template<typename Iterator>\n"; | |
| os_ << "std::size_t " << name_ << " ("; | |
| if (dfas_ > 1 || !optimise_parameters_) | |
| { | |
| os_ << "std::size_t &start_state_, "; | |
| } | |
| if (use_pointers_) | |
| { | |
| os_ << iterator_ << " &"; | |
| } | |
| else | |
| { | |
| os_ << iterator_; | |
| } | |
| os_ << "start_token_, "; | |
| if (use_pointers_) | |
| { | |
| os_ << iterator_ << " const "; | |
| } | |
| else | |
| { | |
| os_ << "const " << iterator_; | |
| } | |
| os_ << "end_, \n"; | |
| os_ << " std::size_t &unique_id_"; | |
| if (sm_._seen_BOL_assertion || !optimise_parameters_) | |
| { | |
| os_ << ", bool &beg_of_line_"; | |
| } | |
| os_ << ")\n"; | |
| os_ << "{\n"; | |
| os_ << " static const std::size_t npos = static_cast" | |
| "<std::size_t>(~0);\n"; | |
| os_ << "\n if (start_token_ == end_)\n"; | |
| os_ << " {\n"; | |
| os_ << " unique_id_ = npos;\n"; | |
| os_ << " return 0;\n"; | |
| os_ << " }\n\n"; | |
| if (dfas_ > 1) | |
| { | |
| os_ << "again:\n"; | |
| } | |
| os_ << " Iterator curr_ = start_token_;\n"; | |
| os_ << " bool end_state_ = false;\n"; | |
| os_ << " std::size_t id_ = npos;\n"; | |
| os_ << " std::size_t uid_ = npos;\n"; | |
| if (dfas_ > 1) | |
| { | |
| os_ << " std::size_t end_start_state_ = start_state_;\n"; | |
| } | |
| if (sm_._seen_BOL_assertion) | |
| { | |
| os_ << " bool bol_ = beg_of_line_;\n"; | |
| os_ << " bool end_bol_ = bol_;\n"; | |
| } | |
| os_ << " Iterator end_token_ = start_token_;\n"; | |
| os_ << '\n'; | |
| if (dfas_ > 1) | |
| { | |
| os_ << " switch (start_state_)\n"; | |
| os_ << " {\n"; | |
| for (std::size_t i_ = 0; i_ < dfas_; ++i_) | |
| { | |
| os_ << " case " << i_ << ":\n"; | |
| os_ << " goto " << i_ << "_0;\n"; | |
| os_ << " // Not needed, but to prevent warnings\n"; | |
| os_ << " break;\n"; | |
| } | |
| os_ << " default:\n"; | |
| os_ << " throw std::runtime_error (\"Invalid start state!\")\n"; | |
| os_ << " break;\n"; | |
| os_ << " }\n\n"; | |
| } | |
| os_ << " "; | |
| if (lookups_ == 256) | |
| { | |
| os_ << "char"; | |
| } | |
| else | |
| { | |
| os_ << "wchar_t"; | |
| } | |
| os_ << " ch_ = 0;\n\n"; | |
| bool need_state0_0_label = need_label0_0(state_machine_); | |
| for (std::size_t dfa_ = 0; dfa_ < dfas_; ++dfa_) | |
| { | |
| const std::size_t states_ = iter_->states; | |
| for (std::size_t state_ = 0; state_ < states_; ++state_) | |
| { | |
| const std::size_t transitions_ = iter_->transitions; | |
| std::size_t t_ = 0; | |
| if (dfas_ > 1 || dfa_ != 0 || state_ != 0 || need_state0_0_label) | |
| { | |
| os_ << "state" << dfa_ << '_' << state_ << ":\n"; | |
| } | |
| if (iter_->end_state) | |
| { | |
| os_ << " end_state_ = true;\n"; | |
| os_ << " id_ = " << iter_->id << ";\n"; | |
| os_ << " uid_ = " << iter_->unique_id << ";\n"; | |
| os_ << " end_token_ = curr_;\n"; | |
| if (dfas_ > 1) | |
| { | |
| os_ << " end_start_state_ = " << iter_->goto_dfa << | |
| ";\n"; | |
| } | |
| if (sm_._seen_BOL_assertion) | |
| { | |
| os_ << " end_bol_ = bol_;\n"; | |
| } | |
| if (transitions_) os_ << '\n'; | |
| } | |
| if (t_ < transitions_ || iter_->bol_index != boost::lexer::npos || | |
| iter_->eol_index != boost::lexer::npos) | |
| { | |
| os_ << " if (curr_ == end_) goto end;\n\n"; | |
| os_ << " ch_ = *curr_;\n"; | |
| if (iter_->bol_index != boost::lexer::npos) | |
| { | |
| os_ << "\n if (bol_) goto state" << dfa_ << '_' << | |
| iter_->bol_index << ";\n\n"; | |
| } | |
| if (iter_->eol_index != boost::lexer::npos) | |
| { | |
| os_ << "\n if (ch_ == '\n') goto state" << dfa_ << '_' << | |
| iter_->eol_index << ";\n\n"; | |
| } | |
| os_ << " ++curr_;\n"; | |
| } | |
| for (; t_ < transitions_; ++t_) | |
| { | |
| const char *ptr_ = iter_->token._charset.c_str(); | |
| const char *end_ = ptr_ + iter_->token._charset.size(); | |
| char start_char_ = 0; | |
| char curr_char_ = 0; | |
| bool range_ = false; | |
| bool first_char_ = true; | |
| os_ << "\n if ("; | |
| while (ptr_ != end_) | |
| { | |
| curr_char_ = *ptr_++; | |
| if (*ptr_ == curr_char_ + 1) | |
| { | |
| if (!range_) | |
| { | |
| start_char_ = curr_char_; | |
| } | |
| range_ = true; | |
| } | |
| else | |
| { | |
| if (!first_char_) | |
| { | |
| if (iter_->token._negated) | |
| { | |
| os_ << " && "; | |
| } | |
| else | |
| { | |
| os_ << " || "; | |
| } | |
| } | |
| first_char_ = false; | |
| if (range_) | |
| { | |
| typename string_token::string temp_; | |
| if (iter_->token._negated) | |
| { | |
| os_ << "!"; | |
| } | |
| string_token::escape_char (start_char_, temp_); | |
| os_ << "(ch_ >= '" << temp_; | |
| #if defined _MSC_VER && _MSC_VER <= 1200 | |
| temp_.erase (); | |
| #else | |
| temp_.clear (); | |
| #endif | |
| string_token::escape_char (curr_char_, temp_); | |
| os_ << "' && ch_ <= '" << temp_ << "')"; | |
| range_ = false; | |
| } | |
| else | |
| { | |
| typename string_token::string temp_; | |
| os_ << "ch_ "; | |
| if (iter_->token._negated) | |
| { | |
| os_ << "!="; | |
| } | |
| else | |
| { | |
| os_ << "=="; | |
| } | |
| string_token::escape_char (curr_char_, temp_); | |
| os_ << " '" << temp_ << "'"; | |
| } | |
| } | |
| } | |
| os_ << ") goto state" << dfa_ << '_' << iter_->goto_state << | |
| ";\n\n"; | |
| ++iter_; | |
| } | |
| if (!(dfa_ == dfas_ - 1 && state_ == states_ - 1)) | |
| { | |
| os_ << " goto end;\n"; | |
| } | |
| if (transitions_ == 0) ++iter_; | |
| } | |
| } | |
| os_ << "end:\n"; | |
| os_ << " if (end_state_)\n"; | |
| os_ << " {\n"; | |
| os_ << " // return longest match\n"; | |
| if (dfas_ > 1) | |
| { | |
| os_ << " start_state_ = end_start_state_;\n"; | |
| } | |
| if (sm_._seen_BOL_assertion && dfas_ < 2) | |
| { | |
| os_ << " beg_of_line_ = end_bol_;\n"; | |
| } | |
| os_ << " start_token_ = end_token_;\n"; | |
| if (dfas_ > 1) | |
| { | |
| os_ << '\n'; | |
| os_ << " if (id_ == 0)\n"; | |
| os_ << " {\n"; | |
| if (sm_._seen_BOL_assertion) | |
| { | |
| os_ << " bol_ = end_bol_;\n"; | |
| } | |
| os_ << " goto again;\n"; | |
| os_ << " }\n"; | |
| if (sm_._seen_BOL_assertion) | |
| { | |
| os_ << " else\n"; | |
| os_ << " {\n"; | |
| os_ << " beg_of_line_ = end_bol_;\n"; | |
| os_ << " }\n"; | |
| } | |
| } | |
| os_ << " }\n"; | |
| os_ << " else\n"; | |
| os_ << " {\n"; | |
| if (sm_._seen_BOL_assertion) | |
| { | |
| os_ << " beg_of_line_ = *start_token_ == '\\n';\n"; | |
| } | |
| if (skip_unknown_) | |
| { | |
| os_ << " // No match causes char to be skipped\n"; | |
| os_ << " ++start_token_;\n"; | |
| } | |
| os_ << " id_ = npos;\n"; | |
| os_ << " uid_ = npos;\n"; | |
| os_ << " }\n"; | |
| os_ << '\n'; | |
| os_ << " unique_id_ = uid_;\n"; | |
| os_ << " return id_;\n"; | |
| os_ << "}\n"; | |
| os_ << "\n#endif\n"; | |
| } | |
| } | |
| } | |
| #endif |