text: #pragma once
  
  #include <functional>
  
  namespace foobar2000_io {
      typedef std::function< void (const char *, t_filestats const & , bool ) > listDirectoryFunc_t;
      void listDirectory( const char * path, abort_callback & aborter, listDirectoryFunc_t func);
  
  #ifdef _WIN32
  	pfc::string8 stripParentFolders( const char * inPath );
  #endif
  
  	void retryOnSharingViolation( std::function<void () > f, double timeout, abort_callback & a);
  	void retryOnSharingViolation( double timeout, abort_callback & a, std::function<void() > f);
  
  	// **** WINDOWS SUCKS ****
  	// Special version of retryOnSharingViolation with workarounds for known MoveFile() bugs.
  	void retryFileMove( double timeout, abort_callback & a, std::function<void()> f);
  
  	// **** WINDOWS SUCKS ****
  	// Special version of retryOnSharingViolation with workarounds for known idiotic problems with folder removal.
  	void retryFileDelete( double timeout, abort_callback & a, std::function<void()> f);
  
  	class listDirectoryCallbackImpl : public directory_callback {
  	public:
  		listDirectoryCallbackImpl() {}
  		listDirectoryCallbackImpl( listDirectoryFunc_t f ) : m_func(f) {}
  		bool on_entry(filesystem * p_owner, abort_callback & p_abort, const char * p_url, bool p_is_subdirectory, const t_filestats & p_stats) {
  			m_func(p_url, p_stats, p_is_subdirectory);
  			return true;
  		}
  		listDirectoryFunc_t m_func;
  	};
  
  #ifdef _WIN32
  	pfc::string8 winGetVolumePath(const char * fb2kPath );
  	DWORD winVolumeFlags( const char * fb2kPath );
  #endif
  }
  
  
  //helper
  class file_path_canonical {
  public:
  	file_path_canonical(const char * src) {filesystem::g_get_canonical_path(src,m_data);}
  	operator const char * () const {return m_data.get_ptr();}
  	const char * get_ptr() const {return m_data.get_ptr();}
  	t_size get_length() const {return m_data.get_length();}
  private:
  	pfc::string8 m_data;
  };
  
  class file_path_display {
  public:
  	file_path_display(const char * src) {filesystem::g_get_display_path(src,m_data);}
  	operator const char * () const {return m_data.get_ptr();}
  	const char * get_ptr() const {return m_data.get_ptr();}
  	t_size get_length() const {return m_data.get_length();}
  private:
  	pfc::string8 m_data;
  };
  
  
  
  class stream_reader_memblock_ref : public stream_reader
  {
  public:
  	template<typename t_array> stream_reader_memblock_ref(const t_array & p_array) : m_data(p_array.get_ptr()), m_data_size(p_array.get_size()), m_pointer(0) {
  		pfc::assert_byte_type<typename t_array::t_item>();
  	}
  	stream_reader_memblock_ref(const void * p_data,t_size p_data_size) : m_data((const unsigned char*)p_data), m_data_size(p_data_size), m_pointer(0) {}
  	stream_reader_memblock_ref() : m_data(NULL), m_data_size(0), m_pointer(0) {}
  	
  	template<typename t_array> void set_data(const t_array & data) {
  		pfc::assert_byte_type<typename t_array::t_item>();
  		set_data(data.get_ptr(), data.get_size());
  	}
  
  	void set_data(const void * data, t_size dataSize) {
  		m_pointer = 0;
  		m_data = reinterpret_cast<const unsigned char*>(data);
  		m_data_size = dataSize;
  	}
  
  	t_size read(void * p_buffer,t_size p_bytes,abort_callback & p_abort) {
  		t_size delta = pfc::min_t(p_bytes, get_remaining());
  		memcpy(p_buffer,m_data+m_pointer,delta);
  		m_pointer += delta;
  		return delta;
  	}
  	void read_object(void * p_buffer,t_size p_bytes,abort_callback & p_abort) {
  		if (p_bytes > get_remaining()) throw exception_io_data_truncation();
  		memcpy(p_buffer,m_data+m_pointer,p_bytes);
  		m_pointer += p_bytes;
  	}
  	t_filesize skip(t_filesize p_bytes,abort_callback & p_abort) {
  		t_size remaining = get_remaining();
  		if (p_bytes >= remaining) {
  			m_pointer = m_data_size; return remaining;
  		} else {
  			m_pointer += (t_size)p_bytes; return p_bytes;
  		}
  	}
  	void skip_object(t_filesize p_bytes,abort_callback & p_abort) {
  		if (p_bytes > get_remaining()) {
  			throw exception_io_data_truncation();
  		} else {
  			m_pointer += (t_size)p_bytes;
  		}
  	}
  	void seek_(t_size offset) {
  		PFC_ASSERT( offset <= m_data_size );
  		m_pointer = offset;
  	}
  	const void * get_ptr_() const {return m_data + m_pointer;}
  	t_size get_remaining() const {return m_data_size - m_pointer;}
  	void reset() {m_pointer = 0;}
  private:
  	const unsigned char * m_data;
  	t_size m_data_size,m_pointer;
  };
  
  class stream_writer_buffer_simple : public stream_writer {
  public:
  	void write(const void * p_buffer,t_size p_bytes,abort_callback & p_abort) {
  		p_abort.check();
  		t_size base = m_buffer.get_size();
  		if (base + p_bytes < base) throw std::bad_alloc();
  		m_buffer.set_size(base + p_bytes);
  		memcpy( (t_uint8*) m_buffer.get_ptr() + base, p_buffer, p_bytes );
  	}
  
  	typedef pfc::array_t<t_uint8,pfc::alloc_fast> t_buffer;
  
  	pfc::array_t<t_uint8,pfc::alloc_fast> m_buffer;
  };
  
  template<class t_storage>
  class stream_writer_buffer_append_ref_t : public stream_writer
  {
  public:
  	stream_writer_buffer_append_ref_t(t_storage & p_output) : m_output(p_output) {}
  	void write(const void * p_buffer,t_size p_bytes,abort_callback & p_abort) {
  		PFC_STATIC_ASSERT( sizeof(m_output[0]) == 1 );
  		p_abort.check();
  		t_size base = m_output.get_size();
  		if (base + p_bytes < base) throw std::bad_alloc();
  		m_output.set_size(base + p_bytes);
  		memcpy( (t_uint8*) m_output.get_ptr() + base, p_buffer, p_bytes );
  	}
  private:
  	t_storage & m_output;
  };
  
  class stream_reader_limited_ref : public stream_reader {
  public:
  	stream_reader_limited_ref(stream_reader * p_reader,t_filesize p_limit) : m_reader(p_reader), m_remaining(p_limit) {}
  	
  	t_size read(void * p_buffer,t_size p_bytes,abort_callback & p_abort) {
  		if (p_bytes > m_remaining) p_bytes = (t_size)m_remaining;
  
  		t_size done = m_reader->read(p_buffer,p_bytes,p_abort);
  		m_remaining -= done;
  		return done;
  	}
  
  	inline t_filesize get_remaining() const {return m_remaining;}
  
  	t_filesize skip(t_filesize p_bytes,abort_callback & p_abort) {
  		if (p_bytes > m_remaining) p_bytes = m_remaining;
  		t_filesize done = m_reader->skip(p_bytes,p_abort);
  		m_remaining -= done;
  		return done;
  	}
  
  	void flush_remaining(abort_callback & p_abort) {
  		if (m_remaining > 0) skip_object(m_remaining,p_abort);
  	}
  
  private:
  	stream_reader * m_reader;
  	t_filesize m_remaining;
  };
  
  class stream_writer_chunk_dwordheader : public stream_writer
  {
  public:
  	stream_writer_chunk_dwordheader(const service_ptr_t<file> & p_writer) : m_writer(p_writer) {}
  
  	void initialize(abort_callback & p_abort) {
  		m_headerposition = m_writer->get_position(p_abort);
  		m_written = 0;
  		m_writer->write_lendian_t((t_uint32)0,p_abort);
  	}
  
  	void finalize(abort_callback & p_abort) {
  		t_filesize end_offset;
  		end_offset = m_writer->get_position(p_abort);
  		m_writer->seek(m_headerposition,p_abort);
  		m_writer->write_lendian_t(pfc::downcast_guarded<t_uint32>(m_written),p_abort);
  		m_writer->seek(end_offset,p_abort);
  	}
  
  	void write(const void * p_buffer,t_size p_bytes,abort_callback & p_abort) {
  		m_writer->write(p_buffer,p_bytes,p_abort);
  		m_written += p_bytes;
  	}
  
  private:
  	service_ptr_t<file> m_writer;
  	t_filesize m_headerposition;
  	t_filesize m_written;
  };
  
  class stream_writer_chunk : public stream_writer
  {
  public:
  	stream_writer_chunk(stream_writer * p_writer) : m_writer(p_writer), m_buffer_state(0) {}
  
  	void write(const void * p_buffer,t_size p_bytes,abort_callback & p_abort);
  
  	void flush(abort_callback & p_abort);//must be called after writing before object is destroyed
  	
  private:
  	stream_writer * m_writer;
  	unsigned m_buffer_state;
  	unsigned char m_buffer[255];
  };
  
  class stream_reader_chunk : public stream_reader
  {
  public:
  	stream_reader_chunk(stream_reader * p_reader) : m_reader(p_reader), m_buffer_state(0), m_buffer_size(0), m_eof(false) {}
  
  	t_size read(void * p_buffer,t_size p_bytes,abort_callback & p_abort);
  
  	void flush(abort_callback & p_abort);//must be called after reading before object is destroyed
  
  	static void g_skip(stream_reader * p_stream,abort_callback & p_abort);
  
  private:
  	stream_reader * m_reader;
  	t_size m_buffer_state, m_buffer_size;
  	bool m_eof;
  	unsigned char m_buffer[255];
  };
  
  class stream_reader_dummy : public stream_reader { t_size read(void * p_buffer,t_size p_bytes,abort_callback & p_abort) {return 0;} };
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  template<bool isBigEndian = false> class stream_reader_formatter {
  public:
  	stream_reader_formatter(stream_reader & p_stream,abort_callback & p_abort) : m_stream(p_stream), m_abort(p_abort) {}
  
  	template<typename t_int> void read_int(t_int & p_out) {
  		if (isBigEndian) m_stream.read_bendian_t(p_out,m_abort);
  		else m_stream.read_lendian_t(p_out,m_abort);
  	}
  
  	void read_raw(void * p_buffer,t_size p_bytes) {
  		m_stream.read_object(p_buffer,p_bytes,m_abort);
  	}
  
  	void skip(t_size p_bytes) {m_stream.skip_object(p_bytes,m_abort);}
  
  	template<typename TArray> void read_raw(TArray& data) {
  		pfc::assert_byte_type<typename TArray::t_item>();
  		read_raw(data.get_ptr(),data.get_size());
  	}
  	template<typename TArray> void read_byte_block(TArray & data) {
  		pfc::assert_byte_type<typename TArray::t_item>();
  		t_uint32 size; read_int(size); data.set_size(size);
  		read_raw(data);
  	}
  	template<typename TArray> void read_array(TArray & data) {
  		t_uint32 size; *this >> size; data.set_size(size);
  		for(t_uint32 walk = 0; walk < size; ++walk) *this >> data[walk];
  	}
  	void read_string_nullterm( pfc::string_base & out ) {
  		m_stream.read_string_nullterm( out, m_abort );
  	}
  	stream_reader & m_stream;
  	abort_callback & m_abort;
  };
  
  template<bool isBigEndian = false> class stream_writer_formatter {
  public:
  	stream_writer_formatter(stream_writer & p_stream,abort_callback & p_abort) : m_stream(p_stream), m_abort(p_abort) {}
  
  	template<typename t_int> void write_int(t_int p_int) {
  		if (isBigEndian) m_stream.write_bendian_t(p_int,m_abort);
  		else m_stream.write_lendian_t(p_int,m_abort);
  	}
  
  	void write_raw(const void * p_buffer,t_size p_bytes) {
  		m_stream.write_object(p_buffer,p_bytes,m_abort);
  	}
  	template<typename TArray> void write_raw(const TArray& data) {
  		pfc::assert_byte_type<typename TArray::t_item>();
  		write_raw(data.get_ptr(),data.get_size());
  	}
  
  	template<typename TArray> void write_byte_block(const TArray& data) {
  		pfc::assert_byte_type<typename TArray::t_item>();
  		write_int( pfc::downcast_guarded<t_uint32>(data.get_size()) );
  		write_raw( data );
  	}
  	template<typename TArray> void write_array(const TArray& data) {
  		const t_uint32 size = pfc::downcast_guarded<t_uint32>(data.get_size());
  		*this << size;
  		for(t_uint32 walk = 0; walk < size; ++walk) *this << data[walk];
  	}
  
  	void write_string(const char * str) {
  		const t_size len = strlen(str);
  		*this << pfc::downcast_guarded<t_uint32>(len);
  		write_raw(str, len);
  	}
  	void write_string(const char * str, t_size len_) {
  		const t_size len = pfc::strlen_max(str, len_);
  		*this << pfc::downcast_guarded<t_uint32>(len);
  		write_raw(str, len);
  	}
  	void write_string_nullterm( const char * str ) {
  		this->write_raw( str, strlen(str)+1 );
  	}
  
  	stream_writer & m_stream;
  	abort_callback & m_abort;
  };
  
  
  #define __DECLARE_INT_OVERLOADS(TYPE)	\
  	template<bool isBigEndian> inline stream_reader_formatter<isBigEndian> & operator>>(stream_reader_formatter<isBigEndian> & p_stream,TYPE & p_int) {typename pfc::sized_int_t<sizeof(TYPE)>::t_unsigned temp;p_stream.read_int(temp); p_int = (TYPE) temp; return p_stream;}	\
  	template<bool isBigEndian> inline stream_writer_formatter<isBigEndian> & operator<<(stream_writer_formatter<isBigEndian> & p_stream,TYPE p_int) {p_stream.write_int((typename pfc::sized_int_t<sizeof(TYPE)>::t_unsigned)p_int); return p_stream;}
  
  __DECLARE_INT_OVERLOADS(char);
  __DECLARE_INT_OVERLOADS(signed char);
  __DECLARE_INT_OVERLOADS(unsigned char);
  __DECLARE_INT_OVERLOADS(signed short);
  __DECLARE_INT_OVERLOADS(unsigned short);
  
  __DECLARE_INT_OVERLOADS(signed int);
  __DECLARE_INT_OVERLOADS(unsigned int);
  
  __DECLARE_INT_OVERLOADS(signed long);
  __DECLARE_INT_OVERLOADS(unsigned long);
  
  __DECLARE_INT_OVERLOADS(signed long long);
  __DECLARE_INT_OVERLOADS(unsigned long long);
  
  __DECLARE_INT_OVERLOADS(wchar_t);
  
  
  #undef __DECLARE_INT_OVERLOADS
  
  template<typename TVal> class _IsTypeByte {
  public:
  	enum {value = pfc::is_same_type<TVal,char>::value || pfc::is_same_type<TVal,unsigned char>::value || pfc::is_same_type<TVal,signed char>::value};
  };
  
  template<bool isBigEndian,typename TVal,size_t Count> stream_reader_formatter<isBigEndian> & operator>>(stream_reader_formatter<isBigEndian> & p_stream,TVal (& p_array)[Count]) {
  	if (_IsTypeByte<TVal>::value) {
  		p_stream.read_raw(p_array,Count);
  	} else {
  		for(t_size walk = 0; walk < Count; ++walk) p_stream >> p_array[walk];
  	}
  	return p_stream;
  }
  
  template<bool isBigEndian,typename TVal,size_t Count> stream_writer_formatter<isBigEndian> & operator<<(stream_writer_formatter<isBigEndian> & p_stream,TVal const (& p_array)[Count]) {
  	if (_IsTypeByte<TVal>::value) {
  		p_stream.write_raw(p_array,Count);
  	} else {
  		for(t_size walk = 0; walk < Count; ++walk) p_stream << p_array[walk];
  	}
  	return p_stream;
  }
  
  #define FB2K_STREAM_READER_OVERLOAD(type) \
  	template<bool isBigEndian> stream_reader_formatter<isBigEndian> & operator>>(stream_reader_formatter<isBigEndian> & stream,type & value)
  
  #define FB2K_STREAM_WRITER_OVERLOAD(type) \
  	template<bool isBigEndian> stream_writer_formatter<isBigEndian> & operator<<(stream_writer_formatter<isBigEndian> & stream,const type & value)
  
  FB2K_STREAM_READER_OVERLOAD(GUID) {
  	return stream >> value.Data1 >> value.Data2 >> value.Data3 >> value.Data4;
  }
  
  FB2K_STREAM_WRITER_OVERLOAD(GUID) {
  	return stream << value.Data1 << value.Data2 << value.Data3 << value.Data4;
  }
  
  FB2K_STREAM_READER_OVERLOAD(pfc::string) {
  	t_uint32 len; stream >> len;
  	value = stream.m_stream.read_string_ex(len,stream.m_abort);
  	return stream;
  }
  
  FB2K_STREAM_WRITER_OVERLOAD(pfc::string) {
  	stream << pfc::downcast_guarded<t_uint32>(value.length());
  	stream.write_raw(value.ptr(),value.length());
  	return stream;
  }
  
  FB2K_STREAM_READER_OVERLOAD(pfc::string_base) {
  	stream.m_stream.read_string(value, stream.m_abort);
  	return stream;
  }
  FB2K_STREAM_WRITER_OVERLOAD(pfc::string_base) {
  	const char * val = value.get_ptr();
  	const t_size len = strlen(val);
  	stream << pfc::downcast_guarded<t_uint32>(len);
  	stream.write_raw(val,len);
  	return stream;
  }
  
  
  FB2K_STREAM_WRITER_OVERLOAD(float) {
  	union {
  		float f; t_uint32 i;
  	} u; u.f = value;
  	return stream << u.i;
  }
  
  FB2K_STREAM_READER_OVERLOAD(float) {
  	union { float f; t_uint32 i;} u;
  	stream >> u.i; value = u.f;
  	return stream;
  }
  
  FB2K_STREAM_WRITER_OVERLOAD(double) {
  	union {
  		double f; t_uint64 i;
  	} u; u.f = value;
  	return stream << u.i;
  }
  
  FB2K_STREAM_READER_OVERLOAD(double) {
  	union { double f; t_uint64 i;} u;
  	stream >> u.i; value = u.f;
  	return stream;
  }
  
  FB2K_STREAM_WRITER_OVERLOAD(bool) {
  	t_uint8 temp = value ? 1 : 0;
  	return stream << temp;
  }
  FB2K_STREAM_READER_OVERLOAD(bool) {
  	t_uint8 temp; stream >> temp; value = temp != 0;
  	return stream;
  }
  
  template<bool BE = false>
  class stream_writer_formatter_simple : public stream_writer_formatter<BE> {
  public:
  	stream_writer_formatter_simple() : stream_writer_formatter<BE>(_m_stream,_m_abort), m_buffer(_m_stream.m_buffer) {}
  
  	typedef stream_writer_buffer_simple::t_buffer t_buffer;
  	t_buffer & m_buffer;
  private:
  	stream_writer_buffer_simple _m_stream;
  	abort_callback_dummy _m_abort;
  };
  
  template<bool BE = false>
  class stream_reader_formatter_simple_ref : public stream_reader_formatter<BE> {
  public:
  	stream_reader_formatter_simple_ref(const void * source, t_size sourceSize) : stream_reader_formatter<BE>(_m_stream,_m_abort), _m_stream(source,sourceSize) {}
  	template<typename TSource> stream_reader_formatter_simple_ref(const TSource& source) : stream_reader_formatter<BE>(_m_stream,_m_abort), _m_stream(source) {}
  	stream_reader_formatter_simple_ref() : stream_reader_formatter<BE>(_m_stream,_m_abort) {}
  
  	void set_data(const void * source, t_size sourceSize) {_m_stream.set_data(source,sourceSize);}
  	template<typename TSource> void set_data(const TSource & source) {_m_stream.set_data(source);}
  
  	void reset() {_m_stream.reset();}
  	t_size get_remaining() {return _m_stream.get_remaining();}
  
  	const void * get_ptr_() const {return _m_stream.get_ptr_();}
  private:
  	stream_reader_memblock_ref _m_stream;
  	abort_callback_dummy _m_abort;
  };
  
  template<bool BE = false>
  class stream_reader_formatter_simple : public stream_reader_formatter_simple_ref<BE> {
  public:
  	stream_reader_formatter_simple() {}
  	stream_reader_formatter_simple(const void * source, t_size sourceSize) {set_data(source,sourceSize);}
  	template<typename TSource> stream_reader_formatter_simple(const TSource & source) {set_data(source);}
  	
  	void set_data(const void * source, t_size sourceSize) {
  		m_content.set_data_fromptr(reinterpret_cast<const t_uint8*>(source), sourceSize);
  		onContentChange();
  	}
  	template<typename TSource> void set_data(const TSource & source) {
  		m_content = source;
  		onContentChange();
  	}
  private:
  	void onContentChange() {
  		stream_reader_formatter_simple_ref<BE>::set_data(m_content);
  	}
  	pfc::array_t<t_uint8> m_content;
  };
  
  
  
  
  
  
  template<bool isBigEndian> class _stream_reader_formatter_translator {
  public:
  	_stream_reader_formatter_translator(stream_reader_formatter<isBigEndian> & stream) : m_stream(stream) {}
  	typedef _stream_reader_formatter_translator<isBigEndian> t_self;
  	template<typename t_what> t_self & operator||(t_what & out) {m_stream >> out; return *this;}
  private:
  	stream_reader_formatter<isBigEndian> & m_stream;
  };
  template<bool isBigEndian> class _stream_writer_formatter_translator {
  public:
  	_stream_writer_formatter_translator(stream_writer_formatter<isBigEndian> & stream) : m_stream(stream) {}
  	typedef _stream_writer_formatter_translator<isBigEndian> t_self;
  	template<typename t_what> t_self & operator||(const t_what & in) {m_stream << in; return *this;}
  private:
  	stream_writer_formatter<isBigEndian> & m_stream;
  };
  
  #define FB2K_STREAM_RECORD_OVERLOAD(type, code) \
  	FB2K_STREAM_READER_OVERLOAD(type) {	\
  		_stream_reader_formatter_translator<isBigEndian> streamEx(stream);	\
  		streamEx || code;	\
  		return stream; \
  	}	\
  	FB2K_STREAM_WRITER_OVERLOAD(type) {	\
  		_stream_writer_formatter_translator<isBigEndian> streamEx(stream);	\
  		streamEx || code;	\
  		return stream;	\
  	}
  
  
  
  
  #define FB2K_RETRY_ON_EXCEPTION(OP, ABORT, TIMEOUT, EXCEPTION) \
  	{	\
  		pfc::lores_timer timer; timer.start();	\
  		for(;;) {	\
  			try { {OP;} break;	}	\
  			catch(EXCEPTION) { if (timer.query() > TIMEOUT) throw;}	\
  			ABORT.sleep(0.05);	\
  		}	\
  	}
  
  #define FB2K_RETRY_ON_EXCEPTION2(OP, ABORT, TIMEOUT, EXCEPTION1, EXCEPTION2) \
  	{	\
  		pfc::lores_timer timer; timer.start();	\
  		for(;;) {	\
  			try { {OP;} break;	}	\
  			catch(EXCEPTION1) { if (timer.query() > TIMEOUT) throw;}	\
  			catch(EXCEPTION2) { if (timer.query() > TIMEOUT) throw;}	\
  			ABORT.sleep(0.05);	\
  		}	\
  	}
  
  #define FB2K_RETRY_ON_EXCEPTION3(OP, ABORT, TIMEOUT, EXCEPTION1, EXCEPTION2, EXCEPTION3) \
  	{	\
  		pfc::lores_timer timer; timer.start();	\
  		for(;;) {	\
  			try { {OP;} break;	}	\
  			catch(EXCEPTION1) { if (timer.query() > TIMEOUT) throw;}	\
  			catch(EXCEPTION2) { if (timer.query() > TIMEOUT) throw;}	\
  			catch(EXCEPTION3) { if (timer.query() > TIMEOUT) throw;}	\
  			ABORT.sleep(0.05);	\
  		}	\
  	}
  
  #define FB2K_RETRY_ON_SHARING_VIOLATION(OP, ABORT, TIMEOUT) FB2K_RETRY_ON_EXCEPTION(OP, ABORT, TIMEOUT, exception_io_sharing_violation)
  
  // **** WINDOWS SUCKS ****
  // File move ops must be retried on all these because you get access-denied when someone is holding open handles to something you're trying to move, or already-exists on something you just told Windows to move away
  #define FB2K_RETRY_FILE_MOVE(OP, ABORT, TIMEOUT) FB2K_RETRY_ON_EXCEPTION3(OP, ABORT, TIMEOUT, exception_io_sharing_violation, exception_io_denied, exception_io_already_exists)
  	
  class fileRestorePositionScope {
  public:
  	fileRestorePositionScope(file::ptr f, abort_callback & a) : m_file(f), m_abort(a) {
  		m_offset = f->get_position(a);
  	}
  	~fileRestorePositionScope() {
  		try {
  			if (!m_abort.is_aborting()) m_file->seek(m_offset, m_abort);
  		} catch(...) {}
  	}
  private:
  	file::ptr m_file;
  	t_filesize m_offset;
  	abort_callback & m_abort;
  };
  
  
  //! Debug self-test function for testing a file object implementation, performs various behavior validity checks, random access etc. Output goes to fb2k console.
  //! Returns true on success, false on failure (buggy file object implementation).
  bool fb2kFileSelfTest(file::ptr f, abort_callback & aborter);
  