Antony Polukhin wrote:
Hi,
Boost.Spirit documentation advices to use multi_pass iterators for parsing files (or reading data to a STL container and then passing the begin and end of the container to Spirit.Qi).
Much better solution would be to use a memory mapped file:
boost::interprocess::file_mapping fm(filename.c_str(), boost::interprocess::read_only);
boost::interprocess::mapped_region region(fm, boost::interprocess::read_only, 0, 0);
const char* begin = reinterpret_cast<const char*>(region.get_address());
const char* const end = b + region.get_size();
I switched from interprocess::file_mapping to iostreams::mapped_file_source because of the formers lack of support for wchar_t/unicode file names. It's also directly usable with boost::filesystem::path. Here's an encapsulation of iterator/range view of the mapped file: #include <boost/filesystem/path.hpp> #include <boost/iostreams/device/mapped_file.hpp> #include <boost/range/iterator_range.hpp> class const_mapped_file { public: typedef boost::filesystem::path Path; typedef const char* Iterator; typedef boost::iterator_range<Iterator> IteratorRange; explicit const_mapped_file(const Path& p) : m_src(p) {} Iterator begin() const { return m_src.data(); } Iterator end() const { return m_src.data() + m_src.size(); } IteratorRange range() const { return IteratorRange(begin(), end()); } private: boost::iostreams::mapped_file_source m_src; }; Jeff