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/*=============================================================================
Boost.Wave: A Standard compliant C++ preprocessor library
Sample demonstrating the usage of advanced preprocessor hooks.
http://www.boost.org/
Copyright (c) 2001-2010 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 <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
#include "advanced_hooks.hpp"
///////////////////////////////////////////////////////////////////////////////
// Main entry point
//
// This sample shows how to use the advanced hooks to output not only the
// preprocessed tokens but also the conditional directives found in the input
// file (these are commented out, tough) and the tokens from inside the
// conditional block which were not evaluated because the corresponding
// condition was false. These tokens are commented out as well.
//
int main(int argc, char *argv[])
{
if (2 != argc) {
std::cerr << "Usage: advanced_hooks 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 instring;
if (!instream.is_open()) {
std::cerr << "Could not open input file: " << argv[1] << std::endl;
return -2;
}
instream.unsetf(std::ios::skipws);
instring = std::string(std::istreambuf_iterator<char>(instream.rdbuf()),
std::istreambuf_iterator<char>());
// The template boost::wave::cpplexer::lex_token<> is the token type to be
// used by the Wave library.
typedef boost::wave::cpplexer::lex_token<> token_type;
// The template boost::wave::cpplexer::lex_iterator<> is the lexer type to
// be used by the Wave library.
typedef boost::wave::cpplexer::lex_iterator<token_type> lex_iterator_type;
// This is the resulting context type to use. The first template parameter
// should match the iterator type to be used during construction of the
// corresponding context object (see below).
typedef boost::wave::context<std::string::iterator, lex_iterator_type,
boost::wave::iteration_context_policies::load_file_to_string,
advanced_preprocessing_hooks
> context_type;
// The preprocessor iterator shouldn't be constructed directly. It is
// to be generated through a wave::context<> object. This wave:context<>
// object additionally may be used to initialize and define different
// parameters of the actual preprocessing (not done here).
//
// The preprocessing of the input stream is done on the fly behind the
// scenes during iteration over the context_type::iterator_type stream.
context_type ctx (instring.begin(), instring.end(), argv[1]);
ctx.set_language(boost::wave::enable_long_long(ctx.get_language()));
ctx.set_language(boost::wave::enable_preserve_comments(ctx.get_language()));
ctx.set_language(boost::wave::enable_prefer_pp_numbers(ctx.get_language()));
// analyze the input file, print out the preprocessed tokens
context_type::iterator_type first = ctx.begin();
context_type::iterator_type last = ctx.end();
while (first != last) {
current_position = (*first).get_position();
std::cout << (*first).get_value();
++first;
}
}
catch (boost::wave::cpp_exception const& e) {
// some preprocessing 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;
}
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