boost/wave/cpplexer/cpp_lex_iterator.hpp
/*=============================================================================
Boost.Wave: A Standard compliant C++ preprocessor library
Definition of the lexer iterator
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_CPP_LEX_ITERATOR_HPP_AF0C37E3_CBD8_4F33_A225_51CF576FA61F_INCLUDED)
#define BOOST_CPP_LEX_ITERATOR_HPP_AF0C37E3_CBD8_4F33_A225_51CF576FA61F_INCLUDED
#include <string>
#include <boost/assert.hpp>
#include <boost/intrusive_ptr.hpp>
#include <boost/wave/wave_config.hpp>
#include <boost/spirit/include/support_multi_pass.hpp>
#include <boost/wave/util/file_position.hpp>
#include <boost/wave/util/functor_input.hpp>
#include <boost/wave/cpplexer/cpp_lex_interface_generator.hpp>
#include <boost/wave/language_support.hpp>
// this must occur after all of the includes and before any code appears
#ifdef BOOST_HAS_ABI_HEADERS
#include BOOST_ABI_PREFIX
#endif
#if 0 != __COMO_VERSION__ || !BOOST_WORKAROUND(BOOST_MSVC, <= 1310)
#define BOOST_WAVE_EOF_PREFIX static
#else
#define BOOST_WAVE_EOF_PREFIX
#endif
///////////////////////////////////////////////////////////////////////////////
namespace boost {
namespace wave {
namespace cpplexer {
namespace impl {
///////////////////////////////////////////////////////////////////////////////
//
// lex_iterator_functor_shim
//
///////////////////////////////////////////////////////////////////////////////
template <typename TokenT>
class lex_iterator_functor_shim
{
typedef typename TokenT::position_type position_type;
public:
lex_iterator_functor_shim()
#if /*0 != __DECCXX_VER || */defined(__PGI)
: eof()
#endif
{}
#if BOOST_WORKAROUND(BOOST_MSVC, <= 1310)
lex_iterator_functor_shim& operator= (lex_iterator_functor_shim const& rhs)
{ return *this; } // nothing to do here
#endif
// interface to the iterator_policies::split_functor_input policy
typedef TokenT result_type;
typedef lex_iterator_functor_shim unique;
typedef lex_input_interface<TokenT>* shared;
BOOST_WAVE_EOF_PREFIX result_type const eof;
template <typename MultiPass>
static result_type& get_next(MultiPass& mp, result_type& result)
{
return mp.shared()->ftor->get(result);
}
// this will be called whenever the last reference to a multi_pass will
// be released
template <typename MultiPass>
static void destroy(MultiPass& mp)
{
delete mp.shared()->ftor;
}
template <typename MultiPass>
static void set_position(MultiPass& mp, position_type const &pos)
{
mp.shared()->ftor->set_position(pos);
}
#if BOOST_WAVE_SUPPORT_PRAGMA_ONCE != 0
template <typename MultiPass>
static bool has_include_guards(MultiPass& mp, std::string& guard_name)
{
return mp.shared()->ftor->has_include_guards(guard_name);
}
#endif
};
///////////////////////////////////////////////////////////////////////////////
// eof token
#if 0 != __COMO_VERSION__ || !BOOST_WORKAROUND(BOOST_MSVC, <= 1310)
template <typename TokenT>
typename lex_iterator_functor_shim<TokenT>::result_type const
lex_iterator_functor_shim<TokenT>::eof;
#endif // 0 != __COMO_VERSION__
///////////////////////////////////////////////////////////////////////////////
} // namespace impl
///////////////////////////////////////////////////////////////////////////////
//
// lex_iterator
//
// A generic C++ lexer interface class, which allows to plug in different
// lexer implementations. The interface between the lexer type used and
// the preprocessor component depends on the token type only (template
// parameter TokenT).
// Additionally, the following requirements apply:
//
// - the lexer type should have a function implemented, which returnes
// the next lexed token from the input stream:
// typename TokenT get();
// - at the end of the input stream this function should return the
// eof token equivalent
// - the lexer should implement a constructor taking two iterators
// pointing to the beginning and the end of the input stream,
// a third parameter containing the name of the parsed input file
// and a 4th parameter of the type boost::wave::language_support
// which specifies, which language subset should be supported (C++,
// C99, C++11 etc.).
//
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
// Divide the given functor type into its components (unique and shared)
// and build a std::pair from these parts
template <typename FunctorData>
struct make_multi_pass
{
typedef
std::pair<typename FunctorData::unique, typename FunctorData::shared>
functor_data_type;
typedef typename FunctorData::result_type result_type;
typedef boost::spirit::iterator_policies::split_functor_input input_policy;
typedef boost::spirit::iterator_policies::ref_counted ownership_policy;
#if defined(BOOST_WAVE_DEBUG)
typedef boost::spirit::iterator_policies::buf_id_check check_policy;
#else
typedef boost::spirit::iterator_policies::no_check check_policy;
#endif
typedef boost::spirit::iterator_policies::split_std_deque storage_policy;
typedef boost::spirit::iterator_policies::default_policy<
ownership_policy, check_policy, input_policy, storage_policy>
policy_type;
typedef boost::spirit::multi_pass<functor_data_type, policy_type> type;
};
///////////////////////////////////////////////////////////////////////////////
template <typename TokenT>
class lex_iterator
: public make_multi_pass<impl::lex_iterator_functor_shim<TokenT> >::type
{
typedef impl::lex_iterator_functor_shim<TokenT> input_policy_type;
typedef typename make_multi_pass<input_policy_type>::type base_type;
typedef typename make_multi_pass<input_policy_type>::functor_data_type
functor_data_type;
typedef typename input_policy_type::unique unique_functor_type;
typedef typename input_policy_type::shared shared_functor_type;
public:
typedef TokenT token_type;
lex_iterator()
{}
template <typename IteratorT>
lex_iterator(IteratorT const &first, IteratorT const &last,
typename TokenT::position_type const &pos,
boost::wave::language_support language)
: base_type(
functor_data_type(
unique_functor_type(),
lex_input_interface_generator<TokenT>
::new_lexer(first, last, pos, language)
)
)
{}
void set_position(typename TokenT::position_type const &pos)
{
typedef typename TokenT::position_type position_type;
// set the new position in the current token
token_type const& currtoken = this->base_type::dereference(*this);
position_type currpos = currtoken.get_position();
currpos.set_file(pos.get_file());
currpos.set_line(pos.get_line());
const_cast<token_type&>(currtoken).set_position(currpos);
// set the new position for future tokens as well
if (token_type::string_type::npos !=
currtoken.get_value().find_first_of('\n'))
{
currpos.set_line(pos.get_line() + 1);
}
unique_functor_type::set_position(*this, currpos);
}
#if BOOST_WAVE_SUPPORT_PRAGMA_ONCE != 0
// return, whether the current file has include guards
// this function returns meaningful results only if the file was scanned
// completely
bool has_include_guards(std::string& guard_name) const
{
return unique_functor_type::has_include_guards(*this, guard_name);
}
#endif
};
///////////////////////////////////////////////////////////////////////////////
} // 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
#undef BOOST_WAVE_EOF_PREFIX
#endif // !defined(BOOST_CPP_LEX_ITERATOR_HPP_AF0C37E3_CBD8_4F33_A225_51CF576FA61F_INCLUDED)
