OpenSceneGraph/include/osg/ref_ptr
2004-09-02 19:10:33 +00:00

102 lines
3.6 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#ifndef OSG_REF_PTR
#define OSG_REF_PTR 1
namespace osg {
/** Smart pointer for handling referenced counted objects.*/
template<class T>
class ref_ptr
{
public:
typedef T element_type;
ref_ptr() :_ptr(0L) {}
ref_ptr(T* t):_ptr(t) { if (_ptr) _ptr->ref(); }
ref_ptr(const ref_ptr& rp):_ptr(rp._ptr) { if (_ptr) _ptr->ref(); }
~ref_ptr() { if (_ptr) _ptr->unref(); _ptr=0; }
inline ref_ptr& operator = (const ref_ptr& rp)
{
if (_ptr==rp._ptr) return *this;
T* tmp_ptr = _ptr;
_ptr = rp._ptr;
if (_ptr) _ptr->ref();
// unref second to prevent any deletion of any object which might
// be referenced by the other object. i.e rp is child of the
// original _ptr.
if (tmp_ptr) tmp_ptr->unref();
return *this;
}
inline ref_ptr& operator = (T* ptr)
{
if (_ptr==ptr) return *this;
T* tmp_ptr = _ptr;
_ptr = ptr;
if (_ptr) _ptr->ref();
// unref second to prevent any deletion of any object which might
// be referenced by the other object. i.e rp is child of the
// original _ptr.
if (tmp_ptr) tmp_ptr->unref();
return *this;
}
// comparison operators for ref_ptr.
inline bool operator == (const ref_ptr& rp) const { return (_ptr==rp._ptr); }
inline bool operator != (const ref_ptr& rp) const { return (_ptr!=rp._ptr); }
inline bool operator < (const ref_ptr& rp) const { return (_ptr<rp._ptr); }
inline bool operator > (const ref_ptr& rp) const { return (_ptr>rp._ptr); }
// comparison operator for const T*.
inline bool operator == (const T* ptr) const { return (_ptr==ptr); }
inline bool operator != (const T* ptr) const { return (_ptr!=ptr); }
inline bool operator < (const T* ptr) const { return (_ptr<ptr); }
inline bool operator > (const T* ptr) const { return (_ptr>ptr); }
inline T& operator*() { return *_ptr; }
inline const T& operator*() const { return *_ptr; }
inline T* operator->() { return _ptr; }
inline const T* operator->() const { return _ptr; }
inline bool operator!() const { return _ptr==0L; }
inline bool valid() const { return _ptr!=0L; }
inline T* get() { return _ptr; }
inline const T* get() const { return _ptr; }
/** take control over the object pointed to by ref_ptr, unreference but do not delete even if ref count goes to 0,
* return the pointer to the object.
* Note, do not use this unless you are 100% sure your code handles the deletion of the object correctly, and
* only use when absolutely required.*/
inline T* take() { return release();}
inline T* release() { T* tmp=_ptr; if (_ptr) _ptr->unref_nodelete(); _ptr=0; return tmp;}
private:
T* _ptr;
};
}
#endif