boost/wave/cpp_iteration_context.hpp
/*=============================================================================
Boost.Wave: A Standard compliant C++ preprocessor library
Definition of the preprocessor context
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(CPP_ITERATION_CONTEXT_HPP_00312288_9DDB_4668_AFE5_25D3994FD095_INCLUDED)
#define CPP_ITERATION_CONTEXT_HPP_00312288_9DDB_4668_AFE5_25D3994FD095_INCLUDED
#include <iterator>
#include <fstream>
#if defined(BOOST_NO_TEMPLATED_ITERATOR_CONSTRUCTORS)
#include <sstream>
#endif
#include <boost/wave/wave_config.hpp>
#include <boost/wave/cpp_exceptions.hpp>
#include <boost/wave/language_support.hpp>
#include <boost/wave/util/file_position.hpp>
// #include <boost/spirit/include/iterator/classic_multi_pass.hpp> // make_multi_pass
// 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 iteration_context_policies {
///////////////////////////////////////////////////////////////////////////////
//
// The iteration_context_policies templates are policies for the
// boost::wave::iteration_context which allows to control, how a given
// input file is to be represented by a pair of iterators pointing to the
// begin and the end of the resulting input sequence.
//
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////
//
// load_file_to_string
//
// Loads a file into a string and returns the iterators pointing to
// the beginning and the end of the loaded string.
//
///////////////////////////////////////////////////////////////////////////
struct load_file_to_string
{
template <typename IterContextT>
class inner
{
public:
template <typename PositionT>
static void init_iterators(IterContextT &iter_ctx,
PositionT const &act_pos, language_support language)
{
typedef typename IterContextT::iterator_type iterator_type;
// read in the file
std::ifstream instream(iter_ctx.filename.c_str());
if (!instream.is_open()) {
BOOST_WAVE_THROW_CTX(iter_ctx.ctx, preprocess_exception,
bad_include_file, iter_ctx.filename.c_str(), act_pos);
return;
}
instream.unsetf(std::ios::skipws);
iter_ctx.instring.assign(
std::istreambuf_iterator<char>(instream.rdbuf()),
std::istreambuf_iterator<char>());
iter_ctx.first = iterator_type(
iter_ctx.instring.begin(), iter_ctx.instring.end(),
PositionT(iter_ctx.filename), language);
iter_ctx.last = iterator_type();
}
private:
std::string instring;
};
};
} // namespace iteration_context_policies
///////////////////////////////////////////////////////////////////////////////
// Base class for iteration contexts
template <typename ContextT, typename IteratorT>
struct base_iteration_context
{
enum file_type
{
// this iteration context handles ...
main_file, // ... the main preprocessed file
system_header, // ... a header file included used #include <>
user_header // ... a header file included using #include ""
};
base_iteration_context(ContextT& ctx_,
BOOST_WAVE_STRINGTYPE const &fname, std::size_t if_block_depth = 0)
: real_filename(fname), real_relative_filename(fname), filename(fname),
line(1), emitted_lines(0), if_block_depth(if_block_depth), ctx(ctx_),
type(main_file)
{}
base_iteration_context(ContextT& ctx_,
IteratorT const &first_, IteratorT const &last_,
BOOST_WAVE_STRINGTYPE const &fname, std::size_t if_block_depth = 0,
file_type type_ = main_file)
: first(first_), last(last_), real_filename(fname),
real_relative_filename(fname), filename(fname),
line(1), emitted_lines(0), if_block_depth(if_block_depth), ctx(ctx_),
type(type_)
{}
// the actual input stream
IteratorT first; // actual input stream position
IteratorT last; // end of input stream
BOOST_WAVE_STRINGTYPE real_filename; // real name of the current file
BOOST_WAVE_STRINGTYPE real_relative_filename; // real relative name of the current file
BOOST_WAVE_STRINGTYPE filename; // actual processed file
unsigned int line; // line counter of underlying stream
unsigned int emitted_lines; // count of emitted newlines
std::size_t if_block_depth; // depth of #if block recursion
ContextT& ctx; // corresponding context<> object
file_type type; // the type of the handled file
};
///////////////////////////////////////////////////////////////////////////////
//
template <
typename ContextT, typename IteratorT,
typename InputPolicyT = typename ContextT::input_policy_type
>
struct iteration_context
: public base_iteration_context<ContextT, IteratorT>,
public InputPolicyT::template
inner<iteration_context<ContextT, IteratorT, InputPolicyT> >
{
typedef IteratorT iterator_type;
typedef typename IteratorT::token_type::position_type position_type;
typedef base_iteration_context<ContextT, IteratorT> base_type;
typedef iteration_context<ContextT, IteratorT, InputPolicyT> self_type;
iteration_context(ContextT& ctx, BOOST_WAVE_STRINGTYPE const &fname,
position_type const &act_pos,
boost::wave::language_support language_,
typename base_type::file_type type = base_type::main_file)
: base_iteration_context<ContextT, IteratorT>(ctx, fname, type)
{
InputPolicyT::template inner<self_type>::init_iterators(
*this, act_pos, language_);
}
};
///////////////////////////////////////////////////////////////////////////////
} // 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(CPP_ITERATION_CONTEXT_HPP_00312288_9DDB_4668_AFE5_25D3994FD095_INCLUDED)
