/*============================================================================= Boost.Wave: A Standard compliant C++ preprocessor library Grammar for universal character validation (see C++ standard: Annex E) http://www.boost.org/ Copyright (c) 2001-2012 Hartmut Kaiser. Distributed under 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) =============================================================================*/ #if !defined(BOOST_CONVERT_TRIGRAPHS_HK050403_INCLUDED) #define BOOST_CONVERT_TRIGRAPHS_HK050403_INCLUDED #include #include // this must occur after all of the includes and before any code appears #ifdef BOOST_HAS_ABI_HEADERS #include BOOST_ABI_PREFIX #endif /////////////////////////////////////////////////////////////////////////////// namespace boost { namespace wave { namespace cpplexer { namespace impl { /////////////////////////////////////////////////////////////////////////////// // // Test, whether the given string represents a valid trigraph sequence // /////////////////////////////////////////////////////////////////////////////// template inline bool is_trigraph(StringT const& trigraph) { if (trigraph.size() < 3 || '?' != trigraph[0] || '?' != trigraph[1]) return false; switch (trigraph[2]) { case '\'': case '=': case '/': case '(': case ')': case '<': case '>': case '!': case '-': break; default: return false; } return true; } /////////////////////////////////////////////////////////////////////////////// // // convert_trigraph // // The function convert_trigraph() converts a single trigraph character // sequence into the corresponding character. // // If the given character sequence doesn't form a valid trigraph sequence // no conversion is performed. // /////////////////////////////////////////////////////////////////////////////// template inline StringT convert_trigraph(StringT const &trigraph) { StringT result (trigraph); if (is_trigraph(trigraph)) { switch (trigraph[2]) { case '\'': result = "^"; break; case '=': result = "#"; break; case '/': result = "\\"; break; case '(': result = "["; break; case ')': result = "]"; break; case '<': result = "{"; break; case '>': result = "}"; break; case '!': result = "|"; break; case '-': result = "~"; break; } } return result; } /////////////////////////////////////////////////////////////////////////////// // // convert_trigraphs // // The function convert_trigraph() converts all trigraphs in the given // string into the corresponding characters. // // If one of the given character sequences doesn't form a valid trigraph // sequence no conversion is performed. // /////////////////////////////////////////////////////////////////////////////// template inline StringT convert_trigraphs(StringT const &value) { StringT result; typename StringT::size_type pos = 0; typename StringT::size_type pos1 = value.find_first_of ("?", 0); if (StringT::npos != pos1) { do { result += value.substr(pos, pos1-pos); StringT trigraph (value.substr(pos1)); if (is_trigraph(trigraph)) { result += convert_trigraph(trigraph); pos1 = value.find_first_of ("?", pos = pos1+3); } else { result += value[pos1]; pos1 = value.find_first_of ("?", pos = pos1+1); } } while (StringT::npos != pos1); result += value.substr(pos); } else { result = value; } return result; } /////////////////////////////////////////////////////////////////////////////// } // namespace impl } // namespace cpplexer } // namespace wave } // namespace boost // the suffix header occurs after all of the code #ifdef BOOST_HAS_ABI_HEADERS #include BOOST_ABI_SUFFIX #endif #endif // !defined(BOOST_CONVERT_TRIGRAPHS_HK050403_INCLUDED)