locale_facets.h

mingw32.rar

       *  do_narrow() is a hook for a derived facet to change the behavior of
       *  narrowing.  do_narrow() must always return the same result for the
       *  same input.
       *
       *  Note: this is not what you want for codepage conversions.  See
       *  codecvt for that.
       *
       *  @param c  The char to convert.
       *  @param dfault  Char to return if conversion fails.
       *  @return  The converted char.
      */
      virtual char
      do_narrow(char_type __c, char) const
      { return __c; }

      /**
       *  @brief  Narrow char array to char array
       *
       *  This virtual function converts each char in the range [lo,hi) to
       *  char using the simplest reasonable transformation and writes the
       *  results to the destination array.  For any char in the input that
       *  cannot be converted, @a dfault is used instead.  For an underived
       *  ctype<char> facet, the argument will be copied unchanged.
       *
       *  do_narrow() is a hook for a derived facet to change the behavior of
       *  narrowing.  do_narrow() must always return the same result for the
       *  same input.
       *
       *  Note: this is not what you want for codepage conversions.  See
       *  codecvt for that.
       *
       *  @param lo  Pointer to start of range.
       *  @param hi  Pointer to end of range.
       *  @param dfault  Char to use if conversion fails.
       *  @param to  Pointer to the destination array.
       *  @return  @a hi.
      */
      virtual const char_type*
      do_narrow(const char_type* __lo, const char_type* __hi,
		char, char* __dest) const
      {
	memcpy(__dest, __lo, __hi - __lo);
	return __hi;
      }

    private:

      void _M_widen_init() const
      {
	char __tmp[sizeof(_M_widen)];
	for (size_t __i = 0; __i < sizeof(_M_widen); ++__i)
	  __tmp[__i] = __i;
	do_widen(__tmp, __tmp + sizeof(__tmp), _M_widen);

	_M_widen_ok = 1;
	// Set _M_widen_ok to 2 if memcpy can't be used.
	for (size_t __j = 0; __j < sizeof(_M_widen); ++__j)
	  if (__tmp[__j] != _M_widen[__j])
	    {
	      _M_widen_ok = 2;
	      break;
	    }
      }

      // Fill in the narrowing cache and flag whether all values are
      // valid or not.  _M_narrow_ok is set to 1 if the whole table is
      // narrowed, 2 if only some values could be narrowed.
      void _M_narrow_init() const
      {
	char __tmp[sizeof(_M_narrow)];
	for (size_t __i = 0; __i < sizeof(_M_narrow); ++__i)
	  __tmp[__i] = __i;
	do_narrow(__tmp, __tmp + sizeof(__tmp), 0, _M_narrow);

	// Check if any default values were created.  Do this by
	// renarrowing with a different default value and comparing.
	bool __consecutive = true;
	for (size_t __j = 0; __j < sizeof(_M_narrow); ++__j)
	  if (!_M_narrow[__j])
	    {
	      char __c;
	      do_narrow(__tmp + __j, __tmp + __j + 1, 1, &__c);
	      if (__c == 1)
		{
		  __consecutive = false;
		  break;
		}
	    }
	_M_narrow_ok = __consecutive ? 1 : 2;
      }
    };

  template<>
    const ctype<char>&
    use_facet<ctype<char> >(const locale& __loc);

#ifdef _GLIBCXX_USE_WCHAR_T
  // 22.2.1.3  ctype<wchar_t> specialization
  /**
   *  @brief  The ctype<wchar_t> specialization.
   *
   *  This class defines classification and conversion functions for the
   *  wchar_t type.  It gets used by wchar_t streams for many I/O operations.
   *  The wchar_t specialization provides a number of optimizations as well.
   *
   *  ctype<wchar_t> inherits its public methods from
   *  __ctype_abstract_base<wchar_t>.
  */
  template<>
    class ctype<wchar_t> : public __ctype_abstract_base<wchar_t>
    {
    public:
      // Types:
      /// Typedef for the template parameter wchar_t.
      typedef wchar_t		char_type;
      typedef wctype_t		__wmask_type;

    protected:
      __c_locale		_M_c_locale_ctype;

      // Pre-computed narrowed and widened chars.
      bool                      _M_narrow_ok;
      char                      _M_narrow[128];
      wint_t                    _M_widen[1 + static_cast<unsigned char>(-1)];

      // Pre-computed elements for do_is.
      mask                      _M_bit[16];
      __wmask_type              _M_wmask[16];

    public:
      // Data Members:
      /// The facet id for ctype<wchar_t>
      static locale::id		id;

      /**
       *  @brief  Constructor performs initialization.
       *
       *  This is the constructor provided by the standard.
       *
       *  @param refs  Passed to the base facet class.
      */
      explicit
      ctype(size_t __refs = 0);

      /**
       *  @brief  Constructor performs static initialization.
       *
       *  This constructor is used to construct the initial C locale facet.
       *
       *  @param cloc  Handle to C locale data.
       *  @param refs  Passed to the base facet class.
      */
      explicit
      ctype(__c_locale __cloc, size_t __refs = 0);

    protected:
      __wmask_type
      _M_convert_to_wmask(const mask __m) const;

      /// Destructor
      virtual
      ~ctype();

      /**
       *  @brief  Test wchar_t classification.
       *
       *  This function finds a mask M for @a c and compares it to mask @a m.
       *
       *  do_is() is a hook for a derived facet to change the behavior of
       *  classifying.  do_is() must always return the same result for the
       *  same input.
       *
       *  @param c  The wchar_t to find the mask of.
       *  @param m  The mask to compare against.
       *  @return  (M & m) != 0.
      */
      virtual bool
      do_is(mask __m, char_type __c) const;

      /**
       *  @brief  Return a mask array.
       *
       *  This function finds the mask for each wchar_t in the range [lo,hi)
       *  and successively writes it to vec.  vec must have as many elements
       *  as the input.
       *
       *  do_is() is a hook for a derived facet to change the behavior of
       *  classifying.  do_is() must always return the same result for the
       *  same input.
       *
       *  @param lo  Pointer to start of range.
       *  @param hi  Pointer to end of range.
       *  @param vec  Pointer to an array of mask storage.
       *  @return  @a hi.
      */
      virtual const char_type*
      do_is(const char_type* __lo, const char_type* __hi, mask* __vec) const;

      /**
       *  @brief  Find wchar_t matching mask
       *
       *  This function searches for and returns the first wchar_t c in
       *  [lo,hi) for which is(m,c) is true.
       *
       *  do_scan_is() is a hook for a derived facet to change the behavior of
       *  match searching.  do_is() must always return the same result for the
       *  same input.
       *
       *  @param m  The mask to compare against.
       *  @param lo  Pointer to start of range.
       *  @param hi  Pointer to end of range.
       *  @return  Pointer to a matching wchar_t if found, else @a hi.
      */
      virtual const char_type*
      do_scan_is(mask __m, const char_type* __lo, const char_type* __hi) const;

      /**
       *  @brief  Find wchar_t not matching mask
       *
       *  This function searches for and returns a pointer to the first
       *  wchar_t c of [lo,hi) for which is(m,c) is false.
       *
       *  do_scan_is() is a hook for a derived facet to change the behavior of
       *  match searching.  do_is() must always return the same result for the
       *  same input.
       *
       *  @param m  The mask to compare against.
       *  @param lo  Pointer to start of range.
       *  @param hi  Pointer to end of range.
       *  @return  Pointer to a non-matching wchar_t if found, else @a hi.
      */
      virtual const char_type*
      do_scan_not(mask __m, const char_type* __lo,
		  const char_type* __hi) const;

      /**
       *  @brief  Convert to uppercase.
       *
       *  This virtual function converts the wchar_t argument to uppercase if
       *  possible.  If not possible (for example, '2'), returns the argument.
       *
       *  do_toupper() is a hook for a derived facet to change the behavior of
       *  uppercasing.  do_toupper() must always return the same result for
       *  the same input.
       *
       *  @param c  The wchar_t to convert.
       *  @return  The uppercase wchar_t if convertible, else @a c.
      */
      virtual char_type
      do_toupper(char_type) const;

      /**
       *  @brief  Convert array to uppercase.
       *
       *  This virtual function converts each wchar_t in the range [lo,hi) to
       *  uppercase if possible.  Other elements remain untouched.
       *
       *  do_toupper() is a hook for a derived facet to change the behavior of
       *  uppercasing.  do_toupper() must always return the same result for
       *  the same input.
       *
       *  @param lo  Pointer to start of range.
       *  @param hi  Pointer to end of range.
       *  @return  @a hi.
      */
      virtual const char_type*
      do_toupper(char_type* __lo, const char_type* __hi) const;

      /**
       *  @brief  Convert to lowercase.
       *
       *  This virtual function converts the argument to lowercase if
       *  possible.  If not possible (for example, '2'), returns the argument.
       *
       *  do_tolower() is a hook for a derived facet to change the behavior of
       *  lowercasing.  do_tolower() must always return the same result for
       *  the same input.
       *
       *  @param c  The wchar_t to convert.
       *  @return  The lowercase wchar_t if convertible, else @a c.
      */
      virtual char_type
      do_tolower(char_type) const;

      /**
       *  @brief  Convert array to lowercase.
       *
       *  This virtual function converts each wchar_t in the range [lo,hi) to
       *  lowercase if possible.  Other elements remain untouched.
       *
       *  do_tolower() is a hook for a derived facet to change the behavior of
       *  lowercasing.  do_tolower() must always return the same result for
       *  the same input.
       *
       *  @param lo  Pointer to start of range.
       *  @param hi  Pointer to end of range.
       *  @return  @a hi.
      */
      virtual const char_type*
      do_tolower(char_type* __lo, const char_type* __hi) const;

      /**
       *  @brief  Widen char to wchar_t
       *
       *  This virtual function converts the char to wchar_t using the
       *  simplest reasonable transformation.  For an underived ctype<wchar_t>
       *  facet, the argument will be cast to wchar_t.
       *
       *  do_widen() is a hook for a derived facet to change the behavior of
       *  widening.  do_widen() must always return the same result for the
       *  same input.
       *
       *  Note: this is not what you want for codepage conversions.  See
       *  codecvt for that.
       *
       *  @param c  The char to convert.
       *  @return  The converted wchar_t.
      */
      virtual char_type
      do_widen(char) const;

      /**
       *  @brief  Widen char array to wchar_t array
       *
       *  This function converts each char in the input to wchar_t using the
       *  simplest reasonable transformation.  For an underived ctype<wchar_t>
       *  facet, the argument will be copied, casting each element to wchar_t.
       *
       *  do_widen() is a hook for a derived facet to change the behavior of
       *  widening.  do_widen() must always return the same result for the
       *  same input.
       *
       *  Note: this is not what you want for codepage conversions.  See
       *  codecvt for that.
       *
       *  @param lo  Pointer to start range.
       *  @param hi  Pointer to end of range.
       *  @param to  Pointer to the destination array.
       *  @return  @a hi.
      */
      virtual const char*
      do_widen(const char* __lo, const char* __hi, char_type* __dest) const;

      /**
       *  @brief  Narrow wchar_t to char
       *
       *  This virtual function converts the argument to char using
       *  the simplest reasonable transformation.  If the conversion
       *  fails, dfault is returned instead.  For an underived
       *  ctype<wchar_t> facet, @a c will be cast to char and
       *  returned.
       *
       *  do_narrow() is a hook for a derived facet to change the
       *  behavior of narrowing.  do_narrow() must always return the
       *  same result for the same input.
       *
       *  Note: this is not what you want for codepage conversions.  See
       *  codecvt for that.
       *
       *  @param c  The wchar_t to convert.
       *  @param dfault  Char to return if conversion fails.
       *  @return  The converted char.
      */
      virtual char
      do_narrow(char_type, char __dfault) const;

      /**
       *  @brief  Narrow wchar_t array to char array
       *