lexed_tokens.cpp

Boost provides free peer-reviewed portable C++ source libraries. We emphasize libraries that work

/*=============================================================================
    Boost.Wave: A Standard compliant C++ preprocessor library

    http://www.boost.org/

    Copyright (c) 2001-2008 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)
=============================================================================*/

#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <vector>

///////////////////////////////////////////////////////////////////////////////
//  Include Wave itself
#include <boost/wave.hpp>

///////////////////////////////////////////////////////////////////////////////
// Include the lexer stuff
#include <boost/wave/cpplexer/cpp_lex_token.hpp>    // token class
#include <boost/wave/cpplexer/cpp_lex_iterator.hpp> // lexer class

///////////////////////////////////////////////////////////////////////////////
//
//  Special output operator for a lex_token.
//
//      Note: this doesn't compile if BOOST_SPIRIT_DEBUG is defined.
//
///////////////////////////////////////////////////////////////////////////////
template <typename PositionT>
inline std::ostream &
operator<< (std::ostream &stream, 
    boost::wave::cpplexer::lex_token<PositionT> const &t)
{
    using namespace std;
    using namespace boost::wave;
    
    token_id id = token_id(t);
    stream << setw(16) 
        << left << boost::wave::get_token_name(id) << " ("
        << "#" << setw(3) << BASEID_FROM_TOKEN(id);

    if (ExtTokenTypeMask & id) {
    // this is an extended token id
        if (AltTokenType == (id & ExtTokenOnlyMask)) {
            stream << ", AltTokenType";
        }
        else if (TriGraphTokenType == (id & ExtTokenOnlyMask)) {
            stream << ", TriGraphTokenType";
        }
        else if (AltExtTokenType == (id & ExtTokenOnlyMask)){
            stream << ", AltExtTokenType";
        }
    }
    
    stream 
        << ") at " << t.get_position().get_file() << " (" 
        << setw(3) << right << t.get_position().get_line() << "/" 
        << setw(2) << right << t.get_position().get_column() 
        << "): >";
    
    typedef typename boost::wave::cpplexer::lex_token<PositionT>::string_type 
        string_type;
        
    string_type const& value = t.get_value();
    for (std::size_t i = 0; i < value.size(); ++i) {
        switch (value[i]) {
        case '\r':  stream << "\\r"; break;
        case '\n':  stream << "\\n"; break;
        case '\t':  stream << "\\t"; break;
        default:
            stream << value[i]; 
            break;
        }
    }
    stream << "<";

    return stream;
}

///////////////////////////////////////////////////////////////////////////////
// main entry point
int main(int argc, char *argv[])
{
    if (2 != argc) {
        std::cerr << "Usage: lexed_tokens infile" << std::endl;
        return -1;
    }
    
// current file position is saved for exception handling
boost::wave::util::file_position_type current_position;

    try {
    //  Open and read in the specified input file.
    std::ifstream instream(argv[1]);
    std::string instr;

        if (!instream.is_open()) {
            std::cerr << "Could not open input file: " << argv[1] << std::endl;
            return -2;
        }
        instream.unsetf(std::ios::skipws);
        instr = std::string(std::istreambuf_iterator<char>(instream.rdbuf()),
                            std::istreambuf_iterator<char>());
            
    // tokenize the input data into C++ tokens using the C++ lexer
        typedef boost::wave::cpplexer::lex_token<> token_type;
        typedef boost::wave::cpplexer::lex_iterator<token_type> lexer_type;
        typedef token_type::position_type position_type;

        position_type pos(argv[1]);
        lexer_type it = lexer_type(instr.begin(), instr.end(), pos, 
            boost::wave::language_support(
                boost::wave::support_cpp|boost::wave::support_option_long_long));
        lexer_type end = lexer_type();

        while (it != end) {
            current_position = (*it).get_position();  // for error reporting
            std::cout << *it << std::endl;            // dump the tokenf info
            ++it;
        }
    }
    catch (boost::wave::cpplexer::lexing_exception const& e) {
    // some lexing error
        std::cerr 
            << e.file_name() << "(" << e.line_no() << "): "
            << e.description() << std::endl;
        return 2;
    }
    catch (std::exception const& e) {
    // use last recognized token to retrieve the error position
        std::cerr 
            << current_position.get_file() 
            << "(" << current_position.get_line() << "): "
            << "exception caught: " << e.what()
            << std::endl;
        return 3;
    }
    catch (...) {
    // use last recognized token to retrieve the error position
        std::cerr 
            << current_position.get_file() 
            << "(" << current_position.get_line() << "): "
            << "unexpected exception caught." << std::endl;
        return 4;
    }
    return 0;
}