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// filesystem path.hpp ---------------------------------------------------------------//
// Copyright Beman Dawes 2002-2005, 2009
// Copyright Vladimir Prus 2002
// Distributed under the Boost Software License, Version 1.0.
// See http://www.boost.org/LICENSE_1_0.txt
// Library home page: http://www.boost.org/libs/filesystem
// path::stem(), extension(), and replace_extension() are based on
// basename(), extension(), and change_extension() from the original
// filesystem/convenience.hpp header by Vladimir Prus.
#ifndef NDNBOOST_FILESYSTEM_PATH_HPP
#define NDNBOOST_FILESYSTEM_PATH_HPP
#include <ndnboost/config.hpp>
# if defined( NDNBOOST_NO_STD_WSTRING )
# error Configuration not supported: Boost.Filesystem V3 and later requires std::wstring support
# endif
#include <ndnboost/filesystem/config.hpp>
#include <ndnboost/filesystem/path_traits.hpp> // includes <cwchar>
#include <ndnboost/system/error_code.hpp>
#include <ndnboost/system/system_error.hpp>
#include <ndnboost/iterator/iterator_facade.hpp>
#include <ndnboost/shared_ptr.hpp>
#include <ndnboost/io/detail/quoted_manip.hpp>
#include <ndnboost/static_assert.hpp>
#include <ndnboost/functional/hash_fwd.hpp>
#include <ndnboost/type_traits/is_integral.hpp>
#include <string>
#include <iterator>
#include <cstring>
#include <iosfwd>
#include <stdexcept>
#include <cassert>
#include <locale>
#include <algorithm>
#include <ndnboost/config/abi_prefix.hpp> // must be the last #include
namespace ndnboost
{
namespace filesystem
{
//------------------------------------------------------------------------------------//
// //
// class path //
// //
//------------------------------------------------------------------------------------//
class NDNBOOST_FILESYSTEM_DECL path
{
public:
// value_type is the character type used by the operating system API to
// represent paths.
# ifdef NDNBOOST_WINDOWS_API
typedef wchar_t value_type;
NDNBOOST_STATIC_CONSTEXPR value_type preferred_separator = L'\\';
# else
typedef char value_type;
NDNBOOST_STATIC_CONSTEXPR value_type preferred_separator = '/';
# endif
typedef std::basic_string<value_type> string_type;
typedef std::codecvt<wchar_t, char,
std::mbstate_t> codecvt_type;
// ----- character encoding conversions -----
// Following the principle of least astonishment, path input arguments
// passed to or obtained from the operating system via objects of
// class path behave as if they were directly passed to or
// obtained from the O/S API, unless conversion is explicitly requested.
//
// POSIX specfies that path strings are passed unchanged to and from the
// API. Note that this is different from the POSIX command line utilities,
// which convert according to a locale.
//
// Thus for POSIX, char strings do not undergo conversion. wchar_t strings
// are converted to/from char using the path locale or, if a conversion
// argument is given, using a conversion object modeled on
// std::wstring_convert.
//
// The path locale, which is global to the thread, can be changed by the
// imbue() function. It is initialized to an implementation defined locale.
//
// For Windows, wchar_t strings do not undergo conversion. char strings
// are converted using the "ANSI" or "OEM" code pages, as determined by
// the AreFileApisANSI() function, or, if a conversion argument is given,
// using a conversion object modeled on std::wstring_convert.
//
// See m_pathname comments for further important rationale.
// TODO: rules needed for operating systems that use / or .
// differently, or format directory paths differently from file paths.
//
// **********************************************************************************
//
// More work needed: How to handle an operating system that may have
// slash characters or dot characters in valid filenames, either because
// it doesn't follow the POSIX standard, or because it allows MBCS
// filename encodings that may contain slash or dot characters. For
// example, ISO/IEC 2022 (JIS) encoding which allows switching to
// JIS x0208-1983 encoding. A valid filename in this set of encodings is
// 0x1B 0x24 0x42 [switch to X0208-1983] 0x24 0x2F [U+304F Kiragana letter KU]
// ^^^^
// Note that 0x2F is the ASCII slash character
//
// **********************************************************************************
// Supported source arguments: half-open iterator range, container, c-array,
// and single pointer to null terminated string.
// All source arguments except pointers to null terminated byte strings support
// multi-byte character strings which may have embedded nulls. Embedded null
// support is required for some Asian languages on Windows.
// [defaults] "const codecvt_type& cvt=codecvt()" default arguments are not used
// because some compilers, such as Microsoft prior to VC++ 10, do not handle defaults
// correctly in templates.
// ----- constructors -----
path(){}
path(const path& p) : m_pathname(p.m_pathname) {}
template <class Source>
path(Source const& source,
typename ndnboost::enable_if<path_traits::is_pathable<
typename ndnboost::decay<Source>::type> >::type* =0)
{
path_traits::dispatch(source, m_pathname, codecvt());
}
// Overloads for the operating system API's native character type. Rationale:
// - Avoids use of codecvt() for native value_type strings. This limits the
// impact of locale("") initialization failures on POSIX systems to programs
// that actually depend on locale(""). It further ensures that exceptions thrown
// as a result of such failues occur after main() has started, so can be caught.
// This is a partial resolution of tickets 4688, 5100, and 5289.
// - A slight optimization for a common use case, particularly on POSIX since
// value_type is char and that is the most common useage.
path(const value_type* s) : m_pathname(s) {}
path(const std::basic_string<value_type>& s) : m_pathname(s) {}
template <class Source>
path(Source const& source, const codecvt_type& cvt)
// see [defaults] note above explaining why codecvt() default arguments are not used
{
path_traits::dispatch(source, m_pathname, cvt);
}
template <class InputIterator>
path(InputIterator begin, InputIterator end)
{
if (begin != end)
{
std::basic_string<typename std::iterator_traits<InputIterator>::value_type>
s(begin, end);
path_traits::convert(s.c_str(), s.c_str()+s.size(), m_pathname, codecvt());
}
}
template <class InputIterator>
path(InputIterator begin, InputIterator end, const codecvt_type& cvt)
{
if (begin != end)
{
std::basic_string<typename std::iterator_traits<InputIterator>::value_type>
s(begin, end);
path_traits::convert(s.c_str(), s.c_str()+s.size(), m_pathname, cvt);
}
}
// ----- assignments -----
path& operator=(const path& p)
{
m_pathname = p.m_pathname;
return *this;
}
path& operator=(const value_type* ptr) // required in case ptr overlaps *this
{
m_pathname = ptr;
return *this;
}
template <class Source>
typename ndnboost::enable_if<path_traits::is_pathable<
typename ndnboost::decay<Source>::type>, path&>::type
operator=(Source const& source)
{
m_pathname.clear();
path_traits::dispatch(source, m_pathname, codecvt());
return *this;
}
path& assign(const value_type* ptr, const codecvt_type&) // required in case ptr overlaps *this
{
m_pathname = ptr;
return *this;
}
template <class Source>
path& assign(Source const& source, const codecvt_type& cvt)
{
m_pathname.clear();
path_traits::dispatch(source, m_pathname, cvt);
return *this;
}
template <class InputIterator>
path& assign(InputIterator begin, InputIterator end)
{
return assign(begin, end, codecvt());
}
template <class InputIterator>
path& assign(InputIterator begin, InputIterator end, const codecvt_type& cvt)
{
m_pathname.clear();
if (begin != end)
{
std::basic_string<typename std::iterator_traits<InputIterator>::value_type>
s(begin, end);
path_traits::convert(s.c_str(), s.c_str()+s.size(), m_pathname, cvt);
}
return *this;
}
// ----- concatenation -----
path& operator+=(const path& p) {m_pathname += p.m_pathname; return *this;}
path& operator+=(const string_type& s) {m_pathname += s; return *this;}
path& operator+=(const value_type* ptr) {m_pathname += ptr; return *this;}
path& operator+=(value_type c) {m_pathname += c; return *this;}
template <class Source>
typename ndnboost::enable_if<path_traits::is_pathable<
typename ndnboost::decay<Source>::type>, path&>::type
operator+=(Source const& source)
{
return concat(source, codecvt());
}
template <class CharT>
typename ndnboost::enable_if<is_integral<CharT>, path&>::type
operator+=(CharT c)
{
CharT tmp[2];
tmp[0] = c;
tmp[1] = 0;
return concat(tmp, codecvt());
}
template <class Source>
path& concat(Source const& source, const codecvt_type& cvt)
{
path_traits::dispatch(source, m_pathname, cvt);
return *this;
}
template <class InputIterator>
path& concat(InputIterator begin, InputIterator end)
{
return concat(begin, end, codecvt());
}
template <class InputIterator>
path& concat(InputIterator begin, InputIterator end, const codecvt_type& cvt)
{
if (begin == end)
return *this;
std::basic_string<typename std::iterator_traits<InputIterator>::value_type>
s(begin, end);
path_traits::convert(s.c_str(), s.c_str()+s.size(), m_pathname, cvt);
return *this;
}
// ----- appends -----
// if a separator is added, it is the preferred separator for the platform;
// slash for POSIX, backslash for Windows
path& operator/=(const path& p);
path& operator/=(const value_type* ptr);
template <class Source>
typename ndnboost::enable_if<path_traits::is_pathable<
typename ndnboost::decay<Source>::type>, path&>::type
operator/=(Source const& source)
{
return append(source, codecvt());
}
path& append(const value_type* ptr, const codecvt_type&) // required in case ptr overlaps *this
{
this->operator/=(ptr);
return *this;
}
template <class Source>
path& append(Source const& source, const codecvt_type& cvt);
template <class InputIterator>
path& append(InputIterator begin, InputIterator end)
{
return append(begin, end, codecvt());
}
template <class InputIterator>
path& append(InputIterator begin, InputIterator end, const codecvt_type& cvt);
// ----- modifiers -----
void clear() { m_pathname.clear(); }
path& make_preferred()
# ifdef NDNBOOST_POSIX_API
{ return *this; } // POSIX no effect
# else // NDNBOOST_WINDOWS_API
; // change slashes to backslashes
# endif
path& remove_filename();
path& replace_extension(const path& new_extension = path());
void swap(path& rhs) { m_pathname.swap(rhs.m_pathname); }
// ----- observers -----
// For operating systems that format file paths differently than directory
// paths, return values from observers are formatted as file names unless there
// is a trailing separator, in which case returns are formatted as directory
// paths. POSIX and Windows make no such distinction.
// Implementations are permitted to return const values or const references.
// The string or path returned by an observer are specified as being formatted
// as "native" or "generic".
//
// For POSIX, these are all the same format; slashes and backslashes are as input and
// are not modified.
//
// For Windows, native: as input; slashes and backslashes are not modified;
// this is the format of the internally stored string.
// generic: backslashes are converted to slashes
// ----- native format observers -----
const string_type& native() const { return m_pathname; } // Throws: nothing
const value_type* c_str() const { return m_pathname.c_str(); } // Throws: nothing
template <class String>
String string() const;
template <class String>
String string(const codecvt_type& cvt) const;
# ifdef NDNBOOST_WINDOWS_API
const std::string string() const { return string(codecvt()); }
const std::string string(const codecvt_type& cvt) const
{
std::string tmp;
if (!m_pathname.empty())
path_traits::convert(&*m_pathname.begin(), &*m_pathname.begin()+m_pathname.size(),
tmp, cvt);
return tmp;
}
// string_type is std::wstring, so there is no conversion
const std::wstring& wstring() const { return m_pathname; }
const std::wstring& wstring(const codecvt_type&) const { return m_pathname; }
# else // NDNBOOST_POSIX_API
// string_type is std::string, so there is no conversion
const std::string& string() const { return m_pathname; }
const std::string& string(const codecvt_type&) const { return m_pathname; }
const std::wstring wstring() const { return wstring(codecvt()); }
const std::wstring wstring(const codecvt_type& cvt) const
{
std::wstring tmp;
if (!m_pathname.empty())
path_traits::convert(&*m_pathname.begin(), &*m_pathname.begin()+m_pathname.size(),
tmp, cvt);
return tmp;
}
# endif
// ----- generic format observers -----
template <class String>
String generic_string() const;
template <class String>
String generic_string(const codecvt_type& cvt) const;
# ifdef NDNBOOST_WINDOWS_API
const std::string generic_string() const { return generic_string(codecvt()); }
const std::string generic_string(const codecvt_type& cvt) const;
const std::wstring generic_wstring() const;
const std::wstring generic_wstring(const codecvt_type&) const { return generic_wstring(); };
# else // NDNBOOST_POSIX_API
// On POSIX-like systems, the generic format is the same as the native format
const std::string& generic_string() const { return m_pathname; }
const std::string& generic_string(const codecvt_type&) const { return m_pathname; }
const std::wstring generic_wstring() const { return wstring(codecvt()); }
const std::wstring generic_wstring(const codecvt_type& cvt) const { return wstring(cvt); }
# endif
// ----- compare -----
int compare(const path& p) const NDNBOOST_NOEXCEPT; // generic, lexicographical
int compare(const std::string& s) const { return compare(path(s)); }
int compare(const value_type* s) const { return compare(path(s)); }
// ----- decomposition -----
path root_path() const;
path root_name() const; // returns 0 or 1 element path
// even on POSIX, root_name() is non-empty() for network paths
path root_directory() const; // returns 0 or 1 element path
path relative_path() const;
path parent_path() const;
path filename() const; // returns 0 or 1 element path
path stem() const; // returns 0 or 1 element path
path extension() const; // returns 0 or 1 element path
// ----- query -----
bool empty() const { return m_pathname.empty(); } // name consistent with std containers
bool has_root_path() const { return has_root_directory() || has_root_name(); }
bool has_root_name() const { return !root_name().empty(); }
bool has_root_directory() const { return !root_directory().empty(); }
bool has_relative_path() const { return !relative_path().empty(); }
bool has_parent_path() const { return !parent_path().empty(); }
bool has_filename() const { return !m_pathname.empty(); }
bool has_stem() const { return !stem().empty(); }
bool has_extension() const { return !extension().empty(); }
bool is_absolute() const
{
# ifdef NDNBOOST_WINDOWS_API
return has_root_name() && has_root_directory();
# else
return has_root_directory();
# endif
}
bool is_relative() const { return !is_absolute(); }
// ----- iterators -----
class iterator;
typedef iterator const_iterator;
iterator begin() const;
iterator end() const;
// ----- static member functions -----
static std::locale imbue(const std::locale& loc);
static const codecvt_type& codecvt();
// ----- deprecated functions -----
# if defined(NDNBOOST_FILESYSTEM_DEPRECATED) && defined(NDNBOOST_FILESYSTEM_NO_DEPRECATED)
# error both NDNBOOST_FILESYSTEM_DEPRECATED and NDNBOOST_FILESYSTEM_NO_DEPRECATED are defined
# endif
# if !defined(NDNBOOST_FILESYSTEM_NO_DEPRECATED)
// recently deprecated functions supplied by default
path& normalize() { return m_normalize(); }
path& remove_leaf() { return remove_filename(); }
path leaf() const { return filename(); }
path branch_path() const { return parent_path(); }
bool has_leaf() const { return !m_pathname.empty(); }
bool has_branch_path() const { return !parent_path().empty(); }
bool is_complete() const { return is_absolute(); }
# endif
# if defined(NDNBOOST_FILESYSTEM_DEPRECATED)
// deprecated functions with enough signature or semantic changes that they are
// not supplied by default
const std::string file_string() const { return string(); }
const std::string directory_string() const { return string(); }
const std::string native_file_string() const { return string(); }
const std::string native_directory_string() const { return string(); }
const string_type external_file_string() const { return native(); }
const string_type external_directory_string() const { return native(); }
// older functions no longer supported
//typedef bool (*name_check)(const std::string & name);
//basic_path(const string_type& str, name_check) { operator/=(str); }
//basic_path(const typename string_type::value_type* s, name_check)
// { operator/=(s);}
//static bool default_name_check_writable() { return false; }
//static void default_name_check(name_check) {}
//static name_check default_name_check() { return 0; }
//basic_path& canonize();
# endif
//--------------------------------------------------------------------------------------//
// class path private members //
//--------------------------------------------------------------------------------------//
private:
# if defined(_MSC_VER)
# pragma warning(push) // Save warning settings
# pragma warning(disable : 4251) // disable warning: class 'std::basic_string<_Elem,_Traits,_Ax>'
# endif // needs to have dll-interface...
/*
m_pathname has the type, encoding, and format required by the native
operating system. Thus for POSIX and Windows there is no conversion for
passing m_pathname.c_str() to the O/S API or when obtaining a path from the
O/S API. POSIX encoding is unspecified other than for dot and slash
characters; POSIX just treats paths as a sequence of bytes. Windows
encoding is UCS-2 or UTF-16 depending on the version.
*/
string_type m_pathname; // Windows: as input; backslashes NOT converted to slashes,
// slashes NOT converted to backslashes
# if defined(_MSC_VER)
# pragma warning(pop) // restore warning settings.
# endif
string_type::size_type m_append_separator_if_needed();
// Returns: If separator is to be appended, m_pathname.size() before append. Otherwise 0.
// Note: An append is never performed if size()==0, so a returned 0 is unambiguous.
void m_erase_redundant_separator(string_type::size_type sep_pos);
string_type::size_type m_parent_path_end() const;
path& m_normalize();
// Was qualified; como433beta8 reports:
// warning #427-D: qualified name is not allowed in member declaration
friend class iterator;
friend bool operator<(const path& lhs, const path& rhs);
// see path::iterator::increment/decrement comment below
static void m_path_iterator_increment(path::iterator & it);
static void m_path_iterator_decrement(path::iterator & it);
}; // class path
namespace detail
{
NDNBOOST_FILESYSTEM_DECL
int lex_compare(path::iterator first1, path::iterator last1,
path::iterator first2, path::iterator last2);
}
# ifndef NDNBOOST_FILESYSTEM_NO_DEPRECATED
typedef path wpath;
# endif
//------------------------------------------------------------------------------------//
// class path::iterator //
//------------------------------------------------------------------------------------//
class path::iterator
: public ndnboost::iterator_facade<
path::iterator,
path const,
ndnboost::bidirectional_traversal_tag >
{
private:
friend class ndnboost::iterator_core_access;
friend class ndnboost::filesystem::path;
friend void m_path_iterator_increment(path::iterator & it);
friend void m_path_iterator_decrement(path::iterator & it);
const path& dereference() const { return m_element; }
bool equal(const iterator & rhs) const
{
return m_path_ptr == rhs.m_path_ptr && m_pos == rhs.m_pos;
}
// iterator_facade derived classes don't seem to like implementations in
// separate translation unit dll's, so forward to class path static members
void increment() { m_path_iterator_increment(*this); }
void decrement() { m_path_iterator_decrement(*this); }
path m_element; // current element
const path* m_path_ptr; // path being iterated over
string_type::size_type m_pos; // position of m_element in
// m_path_ptr->m_pathname.
// if m_element is implicit dot, m_pos is the
// position of the last separator in the path.
// end() iterator is indicated by
// m_pos == m_path_ptr->m_pathname.size()
}; // path::iterator
//------------------------------------------------------------------------------------//
// //
// non-member functions //
// //
//------------------------------------------------------------------------------------//
// std::lexicographical_compare would infinately recurse because path iterators
// yield paths, so provide a path aware version
inline bool lexicographical_compare(path::iterator first1, path::iterator last1,
path::iterator first2, path::iterator last2)
{ return detail::lex_compare(first1, last1, first2, last2) < 0; }
inline bool operator==(const path& lhs, const path& rhs) {return lhs.compare(rhs) == 0;}
inline bool operator==(const path& lhs, const path::string_type& rhs) {return lhs.compare(rhs) == 0;}
inline bool operator==(const path::string_type& lhs, const path& rhs) {return rhs.compare(lhs) == 0;}
inline bool operator==(const path& lhs, const path::value_type* rhs) {return lhs.compare(rhs) == 0;}
inline bool operator==(const path::value_type* lhs, const path& rhs) {return rhs.compare(lhs) == 0;}
inline bool operator!=(const path& lhs, const path& rhs) {return lhs.compare(rhs) != 0;}
inline bool operator!=(const path& lhs, const path::string_type& rhs) {return lhs.compare(rhs) != 0;}
inline bool operator!=(const path::string_type& lhs, const path& rhs) {return rhs.compare(lhs) != 0;}
inline bool operator!=(const path& lhs, const path::value_type* rhs) {return lhs.compare(rhs) != 0;}
inline bool operator!=(const path::value_type* lhs, const path& rhs) {return rhs.compare(lhs) != 0;}
// TODO: why do == and != have additional overloads, but the others don't?
inline bool operator<(const path& lhs, const path& rhs) {return lhs.compare(rhs) < 0;}
inline bool operator<=(const path& lhs, const path& rhs) {return !(rhs < lhs);}
inline bool operator> (const path& lhs, const path& rhs) {return rhs < lhs;}
inline bool operator>=(const path& lhs, const path& rhs) {return !(lhs < rhs);}
inline std::size_t hash_value(const path& x)
{
# ifdef NDNBOOST_WINDOWS_API
std::size_t seed = 0;
for(const path::value_type* it = x.c_str(); *it; ++it)
hash_combine(seed, *it == '/' ? L'\\' : *it);
return seed;
# else // NDNBOOST_POSIX_API
return hash_range(x.native().begin(), x.native().end());
# endif
}
inline void swap(path& lhs, path& rhs) { lhs.swap(rhs); }
inline path operator/(const path& lhs, const path& rhs) { return path(lhs) /= rhs; }
// inserters and extractors
// use ndnboost::io::quoted() to handle spaces in paths
// use '&' as escape character to ease use for Windows paths
template <class Char, class Traits>
inline std::basic_ostream<Char, Traits>&
operator<<(std::basic_ostream<Char, Traits>& os, const path& p)
{
return os
<< ndnboost::io::quoted(p.template string<std::basic_string<Char> >(), static_cast<Char>('&'));
}
template <class Char, class Traits>
inline std::basic_istream<Char, Traits>&
operator>>(std::basic_istream<Char, Traits>& is, path& p)
{
std::basic_string<Char> str;
is >> ndnboost::io::quoted(str, static_cast<Char>('&'));
p = str;
return is;
}
// name_checks
// These functions are holdovers from version 1. It isn't clear they have much
// usefulness, or how to generalize them for later versions.
NDNBOOST_FILESYSTEM_DECL bool portable_posix_name(const std::string & name);
NDNBOOST_FILESYSTEM_DECL bool windows_name(const std::string & name);
NDNBOOST_FILESYSTEM_DECL bool portable_name(const std::string & name);
NDNBOOST_FILESYSTEM_DECL bool portable_directory_name(const std::string & name);
NDNBOOST_FILESYSTEM_DECL bool portable_file_name(const std::string & name);
NDNBOOST_FILESYSTEM_DECL bool native(const std::string & name);
//--------------------------------------------------------------------------------------//
// class path member template implementation //
//--------------------------------------------------------------------------------------//
template <class InputIterator>
path& path::append(InputIterator begin, InputIterator end, const codecvt_type& cvt)
{
if (begin == end)
return *this;
string_type::size_type sep_pos(m_append_separator_if_needed());
std::basic_string<typename std::iterator_traits<InputIterator>::value_type>
s(begin, end);
path_traits::convert(s.c_str(), s.c_str()+s.size(), m_pathname, cvt);
if (sep_pos)
m_erase_redundant_separator(sep_pos);
return *this;
}
template <class Source>
path& path::append(Source const& source, const codecvt_type& cvt)
{
if (path_traits::empty(source))
return *this;
string_type::size_type sep_pos(m_append_separator_if_needed());
path_traits::dispatch(source, m_pathname, cvt);
if (sep_pos)
m_erase_redundant_separator(sep_pos);
return *this;
}
//--------------------------------------------------------------------------------------//
// class path member template specializations //
//--------------------------------------------------------------------------------------//
template <> inline
std::string path::string<std::string>() const
{ return string(); }
template <> inline
std::wstring path::string<std::wstring>() const
{ return wstring(); }
template <> inline
std::string path::string<std::string>(const codecvt_type& cvt) const
{ return string(cvt); }
template <> inline
std::wstring path::string<std::wstring>(const codecvt_type& cvt) const
{ return wstring(cvt); }
template <> inline
std::string path::generic_string<std::string>() const
{ return generic_string(); }
template <> inline
std::wstring path::generic_string<std::wstring>() const
{ return generic_wstring(); }
template <> inline
std::string path::generic_string<std::string>(const codecvt_type& cvt) const
{ return generic_string(cvt); }
template <> inline
std::wstring path::generic_string<std::wstring>(const codecvt_type& cvt) const
{ return generic_wstring(cvt); }
} // namespace filesystem
} // namespace ndnboost
//----------------------------------------------------------------------------//
#include <ndnboost/config/abi_suffix.hpp> // pops abi_prefix.hpp pragmas
#endif // NDNBOOST_FILESYSTEM_PATH_HPP