wxWidgets/include/wx/scopedptr.h
2016-04-12 17:15:23 +02:00

215 lines
7.6 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// 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;
wxEXPLICIT 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
#ifdef __BORLANDC__
// this compiler is too dumb to use unspecified_bool_type operator in tests
// of the form "if ( !ptr )"
typedef bool unspecified_bool_type;
#else
typedef T *(wxScopedPtr<T>::*unspecified_bool_type)() const;
#endif // __BORLANDC__
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: \
wxEXPLICIT 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_