Method append_v4

src/path.cpp:535–593

}

BOOST_FILESYSTEM_DECL void path_algorithms::append_v4(path& p, const value_type* begin, const value_type* end)
{
    if (begin != end)
    {
        if (BOOST_LIKELY(!is_overlapping(p.m_pathname, begin)))
        {
            const size_type that_size = end - begin;
            size_type that_root_name_size = 0;
            size_type that_root_dir_pos = find_root_directory_start(begin, that_size, that_root_name_size);

            // if (p.is_absolute())
            if
            (
#if defined(BOOST_FILESYSTEM_WINDOWS_API)
                that_root_name_size > 0 &&
#endif
                that_root_dir_pos < that_size
            )
            {
            return_assign:
                p.assign(begin, end);
                return;
            }

            size_type this_root_name_size = 0;
            find_root_directory_start(p.m_pathname.c_str(), p.m_pathname.size(), this_root_name_size);

            if
            (
                that_root_name_size > 0 &&
                (that_root_name_size != this_root_name_size || std::memcmp(p.m_pathname.c_str(), begin, this_root_name_size * sizeof(value_type)) != 0)
            )
            {
                goto return_assign;
            }

            if (that_root_dir_pos < that_size)
            {
                // Remove root directory (if any) and relative path to replace with those from p
                p.m_pathname.erase(p.m_pathname.begin() + this_root_name_size, p.m_pathname.end());
            }

            const value_type* const that_path = begin + that_root_name_size;
            if (!detail::is_directory_separator(*that_path))
                path_algorithms::append_separator_if_needed(p);
            p.m_pathname.append(that_path, end);
        }
        else
        {
            // overlapping source
            string_type rhs(begin, end);
            path_algorithms::append_v4(p, rhs.data(), rhs.data() + rhs.size());
        }
    }
    else if (path_algorithms::has_filename_v4(p))
    {
        p.m_pathname.push_back(path::preferred_separator);
    }