RefPtr<> is a reference-counting shared smartpointer. More...
Public Member Functions | |
RefPtr () | |
Default constructor. | |
~RefPtr () | |
Destructor - decrements reference count. | |
RefPtr (T_CppObject* pCppObject) | |
For use only in the internal implementation of cairomm, gtkmm, etc. | |
RefPtr (T_CppObject* pCppObject, int* refcount) | |
For use only in the internal implementation of sharedptr. | |
RefPtr (const RefPtr< T_CppObject >& src) | |
Copy constructor. | |
template<class T_CastFrom > | |
RefPtr (const RefPtr< T_CastFrom >& src) | |
Copy constructor (from different, but castable type). | |
void | swap (RefPtr< T_CppObject >& other) |
Swap the contents of two RefPtr<>. | |
RefPtr< T_CppObject >& | operator= (const RefPtr< T_CppObject >& src) |
Copy from another RefPtr: | |
template<class T_CastFrom > | |
RefPtr< T_CppObject >& | operator= (const RefPtr< T_CastFrom >& src) |
Copy from different, but castable type). | |
bool | operator== (const RefPtr< T_CppObject >& src) const |
Tests whether the RefPtr<> point to the same underlying instance. | |
bool | operator!= (const RefPtr< T_CppObject >& src) const |
See operator==(). | |
T_CppObject* | operator-> () const |
Dereferencing. | |
operator bool () const | |
Test whether the RefPtr<> points to any underlying instance. | |
void | clear () |
Set underlying instance to 0, decrementing reference count of existing instance appropriately. | |
Static Public Member Functions | |
template<class T_CastFrom > | |
static RefPtr< T_CppObject > | cast_dynamic (const RefPtr< T_CastFrom >& src) |
Dynamic cast to derived class. | |
template<class T_CastFrom > | |
static RefPtr< T_CppObject > | cast_static (const RefPtr< T_CastFrom >& src) |
Static cast to derived class. | |
template<class T_CastFrom > | |
static RefPtr< T_CppObject > | cast_const (const RefPtr< T_CastFrom >& src) |
Cast to non-const. |
RefPtr<> is a reference-counting shared smartpointer.
Reference counting means that a shared reference count is incremented each time a RefPtr is copied, and decremented each time a RefPtr is destroyed, for instance when it leaves its scope. When the reference count reaches zero, the contained object is deleted
cairomm uses RefPtr so that you don't need to remember to delete the object explicitly, or know when a method expects you to delete the object that it returns, and to prevent any need to manually reference and unreference() cairo objects.
image-surface.cc, pdf-surface.cc, ps-surface.cc, svg-surface.cc, toy-text.cc, and user-font.cc.
Cairo::RefPtr< T_CppObject >::RefPtr | ( | ) | [inline] |
Default constructor.
Afterwards it will be null and use of -> will cause a segmentation fault.
Cairo::RefPtr< T_CppObject >::~RefPtr | ( | ) | [inline] |
Destructor - decrements reference count.
Cairo::RefPtr< T_CppObject >::RefPtr | ( | T_CppObject * | pCppObject | ) | [inline, explicit] |
For use only in the internal implementation of cairomm, gtkmm, etc.
This takes ownership of pCppObject, so it will be deleted when the last RefPtr is deleted, for instance when it goes out of scope.
This assumes that pCppObject already has a starting reference for its underlying cairo object, so that destruction of will cause a corresponding unreference of its underlying cairo object. For instance, a cairo_*_create() function usually provides a starting reference, but a cairo_*_get_*() function requires the caller to manually reference the returned object. In this case, you should call reference() on pCppObject before passing it to this constructor.
Cairo::RefPtr< T_CppObject >::RefPtr | ( | T_CppObject * | pCppObject, | |
int * | refcount | |||
) | [inline, explicit] |
For use only in the internal implementation of sharedptr.
Cairo::RefPtr< T_CppObject >::RefPtr | ( | const RefPtr< T_CppObject >& | src | ) | [inline] |
Copy constructor.
This increments the shared reference count.
Cairo::RefPtr< T_CppObject >::RefPtr | ( | const RefPtr< T_CastFrom >& | src | ) | [inline] |
Copy constructor (from different, but castable type).
Increments the reference count.
static RefPtr<T_CppObject> Cairo::RefPtr< T_CppObject >::cast_const | ( | const RefPtr< T_CastFrom >& | src | ) | [inline, static] |
Cast to non-const.
The RefPtr can't be cast with the usual notation so instead you can use
ptr_unconst = RefPtr<UnConstType>::cast_const(ptr_const);
static RefPtr<T_CppObject> Cairo::RefPtr< T_CppObject >::cast_dynamic | ( | const RefPtr< T_CastFrom >& | src | ) | [inline, static] |
Dynamic cast to derived class.
The RefPtr can't be cast with the usual notation so instead you can use
ptr_derived = RefPtr<Derived>::cast_dynamic(ptr_base);
static RefPtr<T_CppObject> Cairo::RefPtr< T_CppObject >::cast_static | ( | const RefPtr< T_CastFrom >& | src | ) | [inline, static] |
Static cast to derived class.
Like the dynamic cast; the notation is
ptr_derived = RefPtr<Derived>::cast_static(ptr_base);
void Cairo::RefPtr< T_CppObject >::clear | ( | ) | [inline] |
Set underlying instance to 0, decrementing reference count of existing instance appropriately.
Cairo::RefPtr< T_CppObject >::operator bool | ( | ) | const [inline] |
Test whether the RefPtr<> points to any underlying instance.
Mimics usage of ordinary pointers:
if (ptr)
do_something();
bool Cairo::RefPtr< T_CppObject >::operator!= | ( | const RefPtr< T_CppObject >& | src | ) | const [inline] |
See operator==().
T_CppObject* Cairo::RefPtr< T_CppObject >::operator-> | ( | ) | const [inline] |
Dereferencing.
Use the methods of the underlying instance like so: refptr->memberfun()
.
RefPtr<T_CppObject>& Cairo::RefPtr< T_CppObject >::operator= | ( | const RefPtr< T_CppObject >& | src | ) | [inline] |
Copy from another RefPtr:
RefPtr<T_CppObject>& Cairo::RefPtr< T_CppObject >::operator= | ( | const RefPtr< T_CastFrom >& | src | ) | [inline] |
Copy from different, but castable type).
Increments the reference count.
bool Cairo::RefPtr< T_CppObject >::operator== | ( | const RefPtr< T_CppObject >& | src | ) | const [inline] |
Tests whether the RefPtr<> point to the same underlying instance.
void Cairo::RefPtr< T_CppObject >::swap | ( | RefPtr< T_CppObject >& | other | ) | [inline] |
Swap the contents of two RefPtr<>.
This method swaps the internal pointers to T_CppObject. This can be done safely without involving a reference/unreference cycle and is therefore highly efficient.