///////////////////////////////////////////////////////////////////////////// // Name: wx/scopedptr.h // Purpose: scoped smart pointer class // Author: Jesse Lovelace <jllovela@eos.ncsu.edu> // Created: 06/01/02 // Copyright: (c) Jesse Lovelace and original Boost authors (see below) // (c) 2009 Vadim Zeitlin // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// // This class closely follows the implementation of the boost // library scoped_ptr and is an adaptation for c++ macro's in // the wxWidgets project. The original authors of the boost // scoped_ptr are given below with their respective copyrights. // (C) Copyright Greg Colvin and Beman Dawes 1998, 1999. // Copyright (c) 2001, 2002 Peter Dimov // // Permission to copy, use, modify, sell and distribute this software // is granted provided this copyright notice appears in all copies. // This software is provided "as is" without express or implied // warranty, and with no claim as to its suitability for any purpose. // // See http://www.boost.org/libs/smart_ptr/scoped_ptr.htm for documentation. // #ifndef _WX_SCOPED_PTR_H_ #define _WX_SCOPED_PTR_H_ #include "wx/defs.h" #include "wx/checkeddelete.h" // ---------------------------------------------------------------------------- // wxScopedPtr: A scoped pointer // ---------------------------------------------------------------------------- template <class T> class wxScopedPtr { public: typedef T element_type; explicit wxScopedPtr(T * ptr = NULL) : m_ptr(ptr) { } ~wxScopedPtr() { wxCHECKED_DELETE(m_ptr); } // test for pointer validity: defining conversion to unspecified_bool_type // and not more obvious bool to avoid implicit conversions to integer types typedef T *(wxScopedPtr<T>::*unspecified_bool_type)() const; operator unspecified_bool_type() const { return m_ptr ? &wxScopedPtr<T>::get : NULL; } void reset(T * ptr = NULL) { if ( ptr != m_ptr ) { wxCHECKED_DELETE(m_ptr); m_ptr = ptr; } } T *release() { T *ptr = m_ptr; m_ptr = NULL; return ptr; } T & operator*() const { wxASSERT(m_ptr != NULL); return *m_ptr; } T * operator->() const { wxASSERT(m_ptr != NULL); return m_ptr; } T * get() const { return m_ptr; } void swap(wxScopedPtr& other) { T * const tmp = other.m_ptr; other.m_ptr = m_ptr; m_ptr = tmp; } private: T * m_ptr; wxDECLARE_NO_COPY_TEMPLATE_CLASS(wxScopedPtr, T); }; // ---------------------------------------------------------------------------- // old macro based implementation // ---------------------------------------------------------------------------- /* The type being used *must* be complete at the time that wxDEFINE_SCOPED_* is called or a compiler error will result. This is because the class checks for the completeness of the type being used. */ #define wxDECLARE_SCOPED_PTR(T, name) \ class name \ { \ private: \ T * m_ptr; \ \ name(name const &); \ name & operator=(name const &); \ \ public: \ explicit name(T * ptr = NULL) \ : m_ptr(ptr) { } \ \ ~name(); \ \ void reset(T * ptr = NULL); \ \ T *release() \ { \ T *ptr = m_ptr; \ m_ptr = NULL; \ return ptr; \ } \ \ T & operator*() const \ { \ wxASSERT(m_ptr != NULL); \ return *m_ptr; \ } \ \ T * operator->() const \ { \ wxASSERT(m_ptr != NULL); \ return m_ptr; \ } \ \ T * get() const \ { \ return m_ptr; \ } \ \ void swap(name & ot) \ { \ T * tmp = ot.m_ptr; \ ot.m_ptr = m_ptr; \ m_ptr = tmp; \ } \ }; #define wxDEFINE_SCOPED_PTR(T, name)\ void name::reset(T * ptr) \ { \ if (m_ptr != ptr) \ { \ wxCHECKED_DELETE(m_ptr); \ m_ptr = ptr; \ } \ } \ name::~name() \ { \ wxCHECKED_DELETE(m_ptr); \ } // this macro can be used for the most common case when you want to declare and // define the scoped pointer at the same time and want to use the standard // naming convention: auto pointer to Foo is called FooPtr #define wxDEFINE_SCOPED_PTR_TYPE(T) \ wxDECLARE_SCOPED_PTR(T, T ## Ptr) \ wxDEFINE_SCOPED_PTR(T, T ## Ptr) // ---------------------------------------------------------------------------- // "Tied" scoped pointer: same as normal one but also sets the value of // some other variable to the pointer value // ---------------------------------------------------------------------------- #define wxDEFINE_TIED_SCOPED_PTR_TYPE(T) \ wxDEFINE_SCOPED_PTR_TYPE(T) \ class T ## TiedPtr : public T ## Ptr \ { \ public: \ T ## TiedPtr(T **pp, T *p) \ : T ## Ptr(p), m_pp(pp) \ { \ m_pOld = *pp; \ *pp = p; \ } \ \ ~ T ## TiedPtr() \ { \ *m_pp = m_pOld; \ } \ \ private: \ T **m_pp; \ T *m_pOld; \ }; #endif // _WX_SCOPED_PTR_H_