// Position types -*- C++ -*-
-// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2003
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
+// 2006, 2007, 2008
// Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
-// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.
// As a special exception, you may use this file as part of a free software
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
-//
-// ISO C++ 14882: 27.4.1 - Types
-// ISO C++ 14882: 27.4.3 - Template class fpos
-//
-
/** @file postypes.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
+//
+// ISO C++ 14882: 27.4.1 - Types
+// ISO C++ 14882: 27.4.3 - Template class fpos
+//
+
#ifndef _GLIBCXX_POSTYPES_H
#define _GLIBCXX_POSTYPES_H 1
#include <cwchar> // For mbstate_t
-#ifdef _GLIBCXX_HAVE_STDINT_H
-#include <stdint.h> // For int64_t
-#endif
+_GLIBCXX_BEGIN_NAMESPACE(std)
-namespace std
-{
// The types streamoff, streampos and wstreampos and the class
// template fpos<> are described in clauses 21.1.2, 21.1.3, 27.1.2,
- // 27.2, 27.4.1, 27.4.3 and D.6. Despite all this verbage, the
+ // 27.2, 27.4.1, 27.4.3 and D.6. Despite all this verbiage, the
// behaviour of these types is mostly implementation defined or
// unspecified. The behaviour in this implementation is as noted
// below.
+ /**
+ * @brief Type used by fpos, char_traits<char>, and char_traits<wchar_t>.
+ *
+ * In clauses 21.1.3.1 and 27.4.1 streamoff is described as an
+ * implementation defined type.
+ * Note: In versions of GCC up to and including GCC 3.3, streamoff
+ * was typedef long.
+ */
#ifdef _GLIBCXX_HAVE_INT64_T
- typedef int64_t __streamoff_base_type;
+# if (__CHAR_BIT__ * __SIZEOF_LONG__ == 64)
+ typedef long streamoff;
+# else
+ typedef long long streamoff;
+# endif
#else
- typedef long long __streamoff_base_type;
+ typedef long long streamoff;
#endif
+ /// Integral type for I/O operation counts and buffer sizes.
typedef ptrdiff_t streamsize; // Signed integral type
- template<typename _StateT>
- class fpos;
-
- // Class streamoff is an implementation defined type that meets the
- // requirements for streamoff. It stores an offset as a signed
- // integer. Note: this class is an implementation detail.
- class streamoff
- {
- private:
- __streamoff_base_type _M_off;
-
- public:
- // Nothing in the standard requires that streamoff can be default
- // constructed. In this implementation a default constructor that
- // stores the value 0 is provided.
- streamoff()
- : _M_off(0) { }
-
- // The standard only requires that streamoff can be constructed
- // from streamsize using the constructor syntax. This
- // implementation also allows implicit conversion from integer
- // types to streamoff.
- streamoff(__streamoff_base_type __off)
- : _M_off(__off) { }
-
- // The standard requires that streamoff can be constructed from
- // instances of fpos using the constructor syntax, but gives no
- // semantics for this construction. In this implementation it
- // extracts the offset stored by the fpos object.
- // Note: In versions of GCC up to and including GCC 3.3, implicit
- // conversion from fpos to streamoff was allowed. This constructor
- // has now been made explicit to improve type safety.
- template<typename _StateT>
- explicit
- streamoff(const fpos<_StateT>&);
-
- // The standard requires that streamsize can be constructed from
- // streamoff using the constructor syntax. This implementation
- // also allows implicit conversion. This allows streamoff objects
- // to be used in arithmetic expressions and to be compared against
- // each other and integer types.
- operator __streamoff_base_type() const
- { return _M_off; }
-
- // This implementation allows the use of operators +=, -=, ++ and
- // -- on streamoff objects.
- streamoff&
- operator+=(__streamoff_base_type __off)
- {
- _M_off += __off;
- return *this;
- }
-
- streamoff&
- operator-=(__streamoff_base_type __off)
- {
- _M_off -= __off;
- return *this;
- }
- };
-
- // In clauses 21.1.3.1 and 27.4.1 streamoff is described as an
- // implementation defined type. In this implementation it is a
- // distinct class type.
- // Note: In versions of GCC up to and including GCC 3.3, streamoff
- // was typedef long.
- typedef class streamoff streamoff;
-
- // The standard fails to place any requiremens on the template
- // argument StateT. In this implementation StateT must be
- // DefaultConstructible, CopyConstructible and Assignable. The
- // standard only requires that fpos should contain a member of type
- // StateT. In this implementation it also contains an offset stored
- // as a signed integer.
+ /**
+ * @brief Class representing stream positions.
+ *
+ * The standard places no requirements upon the template parameter StateT.
+ * In this implementation StateT must be DefaultConstructible,
+ * CopyConstructible and Assignable. The standard only requires that fpos
+ * should contain a member of type StateT. In this implementation it also
+ * contains an offset stored as a signed integer.
+ *
+ * @param StateT Type passed to and returned from state().
+ */
template<typename _StateT>
class fpos
{
private:
- friend class streamoff;
-
- __streamoff_base_type _M_off;
- _StateT _M_state;
+ streamoff _M_off;
+ _StateT _M_state;
public:
// The standard doesn't require that fpos objects can be default
fpos()
: _M_off(0), _M_state() { }
- // The standard requires implicit conversion from integers to
- // fpos, but gives no meaningful semantics for this
- // conversion. In this implementation this constructor stores
- // the integer as the offset and default constructs the state.
- fpos(__streamoff_base_type __off)
- : _M_off(__off), _M_state() { }
-
// The standard requires that fpos objects can be constructed
// from streamoff objects using the constructor syntax, and
// fails to give any meaningful semantics. In this
// implementation implicit conversion is also allowed, and this
// constructor stores the streamoff as the offset and default
// constructs the state.
- fpos(const streamoff& __off)
+ /// Construct position from offset.
+ fpos(streamoff __off)
: _M_off(__off), _M_state() { }
+ /// Convert to streamoff.
+ operator streamoff() const { return _M_off; }
+
+ /// Remember the value of @a st.
void
state(_StateT __st)
{ _M_state = __st; }
+ /// Return the last set value of @a st.
_StateT
state() const
{ return _M_state; }
- // The standard only requires that operator== must be an
- // equivalence relation. In this implementation two fpos<StateT>
- // objects belong to the same equivalence class if the contained
- // offsets compare equal.
- bool
- operator==(const fpos& __other) const
- { return _M_off == __other._M_off; }
-
- bool
- operator!=(const fpos& __other) const
- { return _M_off != __other._M_off; }
-
// The standard requires that this operator must be defined, but
- // gives no semantics. In this implemenation it just adds it's
+ // gives no semantics. In this implementation it just adds its
// argument to the stored offset and returns *this.
+ /// Add offset to this position.
fpos&
- operator+=(const streamoff& __off)
+ operator+=(streamoff __off)
{
_M_off += __off;
return *this;
}
// The standard requires that this operator must be defined, but
- // gives no semantics. In this implemenation it just subtracts
- // it's argument from the stored offset and returns *this.
+ // gives no semantics. In this implementation it just subtracts
+ // its argument from the stored offset and returns *this.
+ /// Subtract offset from this position.
fpos&
- operator-=(const streamoff& __off)
+ operator-=(streamoff __off)
{
_M_off -= __off;
return *this;
}
// The standard requires that this operator must be defined, but
- // defines it's semantics only in terms of operator-. In this
+ // defines its semantics only in terms of operator-. In this
// implementation it constructs a copy of *this, adds the
// argument to that copy using operator+= and then returns the
// copy.
+ /// Add position and offset.
fpos
- operator+(const streamoff& __off) const
+ operator+(streamoff __off) const
{
fpos __pos(*this);
__pos += __off;
}
// The standard requires that this operator must be defined, but
- // defines it's semantics only in terms of operator+. In this
+ // defines its semantics only in terms of operator+. In this
// implementation it constructs a copy of *this, subtracts the
// argument from that copy using operator-= and then returns the
// copy.
+ /// Subtract offset from position.
fpos
- operator-(const streamoff& __off) const
+ operator-(streamoff __off) const
{
fpos __pos(*this);
__pos -= __off;
}
// The standard requires that this operator must be defined, but
- // defines it's semantics only in terms of operator+. In this
+ // defines its semantics only in terms of operator+. In this
// implementation it returns the difference between the offset
// stored in *this and in the argument.
+ /// Subtract position to return offset.
streamoff
operator-(const fpos& __other) const
{ return _M_off - __other._M_off; }
};
+ // The standard only requires that operator== must be an
+ // equivalence relation. In this implementation two fpos<StateT>
+ // objects belong to the same equivalence class if the contained
+ // offsets compare equal.
+ /// Test if equivalent to another position.
+ template<typename _StateT>
+ inline bool
+ operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
+ { return streamoff(__lhs) == streamoff(__rhs); }
+
template<typename _StateT>
- inline
- streamoff::streamoff(const fpos<_StateT>& __pos)
- : _M_off(__pos._M_off) { }
+ inline bool
+ operator!=(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
+ { return streamoff(__lhs) != streamoff(__rhs); }
// Clauses 21.1.3.1 and 21.1.3.2 describe streampos and wstreampos
// as implementation defined types, but clause 27.2 requires that
// they must both be typedefs for fpos<mbstate_t>
+ /// File position for char streams.
typedef fpos<mbstate_t> streampos;
+ /// File position for wchar_t streams.
typedef fpos<mbstate_t> wstreampos;
-} // namespace std
+
+_GLIBCXX_END_NAMESPACE
#endif
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