added tied scoped pointers

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@23638 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/docs/latex/wx/scpdptr.tex b/docs/latex/wx/scpdptr.tex
index fe3d8cebafbba586c30519b543ded0c66372feb3..8f9ebf4185721bb89ef827bd160aeb93136dfef5 100644 (file)
--- a/docs/latex/wx/scpdptr.tex
+++ b/docs/latex/wx/scpdptr.tex
@@ -86,11 +86,19 @@ Once again, in this cass \texttt{CLASSNAME} will be \texttt{TYPEPtr}.
 
 \membersection{wxScopedPtr::wxScopedPtr}
 
 
 \membersection{wxScopedPtr::wxScopedPtr}
 

-\func{}{wxScopedPtr}{\param{type}{ * T = NULL}}
+\func{}{explicit wxScopedPtr}{\param{type}{ * T = NULL}}

 
 

-Creates the smart pointer with the given pointer or none if NULL.  On
+Creates the smart pointer with the given pointer or none if {\tt NULL}.  On

 compilers that support it, this uses the explicit keyword.
 
 compilers that support it, this uses the explicit keyword.
 

+
+\membersection{wxScopedPtr::\destruct{wxScopedPtr}
+
+\func{}{\destruct{wxScopedPtr}}{\void}
+
+Destructor frees the pointer help by this object if it is not {\t NULL}.
+
+

 \membersection{wxScopedPtr::release}
 
 \func{T *}{release}{\void}
 \membersection{wxScopedPtr::release}
 
 \func{T *}{release}{\void}


@@ -108,6 +116,7 @@ Deletes the currently held pointer and sets it to {\it p} or to NULL if no
 arguments are specified. This function does check to make sure that the
 pointer you are assigning is not the same pointer that is already stored.
 
 arguments are specified. This function does check to make sure that the
 pointer you are assigning is not the same pointer that is already stored.
 

+

 \membersection{wxScopedPtr::operator *}
 
 \func{const T\&}{operator *}{\void}
 \membersection{wxScopedPtr::operator *}
 
 \func{const T\&}{operator *}{\void}


@@ -116,6 +125,7 @@ This operator works like the standard C++ pointer operator to return the object
 being pointed to by the pointer.  If the pointer is NULL or invalid this will
 crash.
 
 being pointed to by the pointer.  If the pointer is NULL or invalid this will
 crash.
 

+

 \membersection{wxScopedPtr::operator -$>$} % TODO
 
 \func{const T*}{operator -$>$}{\void} % TODO
 \membersection{wxScopedPtr::operator -$>$} % TODO
 
 \func{const T*}{operator -$>$}{\void} % TODO


@@ -123,6 +133,7 @@ crash.
 This operator works like the standard C++ pointer operator to return the pointer
 in the smart pointer or NULL if it is empty.
 
 This operator works like the standard C++ pointer operator to return the pointer
 in the smart pointer or NULL if it is empty.
 

+

 \membersection{wxScopedPtr::get}
 
 \func{const T*}{get}{\void}
 \membersection{wxScopedPtr::get}
 
 \func{const T*}{get}{\void}


@@ -130,6 +141,7 @@ in the smart pointer or NULL if it is empty.
 This operator gets the pointer stored in the smart pointer or returns NULL if
 there is none.
 
 This operator gets the pointer stored in the smart pointer or returns NULL if
 there is none.
 

+

 \membersection{wxScopedPtr::swap}
 
 \func{\void}{swap}{\param{wxScopedPtr}{ \& other}}
 \membersection{wxScopedPtr::swap}
 
 \func{\void}{swap}{\param{wxScopedPtr}{ \& other}}


@@ -137,3 +149,50 @@ there is none.
 Swap the pointer inside the smart pointer with {\it other}. The pointer being
 swapped must be of the same type (hence the same class name).
 
 Swap the pointer inside the smart pointer with {\it other}. The pointer being
 swapped must be of the same type (hence the same class name).
 

+
+
+
+%%%%%%% wxScopedTiedPtr %%%%%%%
+\section{\class{wxScopedTiedPtr}}\label{wxscopedtiedptr}
+
+This is a variation on the topic of \helpref{wxScopedPtr}{wxscopedptr}. This
+class is also a smart pointer but in addition it ``ties'' the pointer value to
+another variable. In other words, during the life time of this class the value
+of that variable is set to be the same as the value of the pointer itself and
+it is reset to its old value when the object is destroyed. This class is
+especially useful when converting the existing code (which may already store
+the pointers value in some variable) to the smart pointers.
+
+\wxheading{Example}
+
+\wxheading{Derives from}
+
+\helpref{wxScopedPtr}{wxscopedptr}
+
+\wxheading{Include files}
+
+<wx/ptr\_scpd.h>
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxScopedTiedPtr::wxScopedTiedPtr}\label{wxscopedtiedptrctor}
+
+\func{}{wxScopedTiedPtr}{\param{T **}{ppTie}, \param{T *}{ptr}}
+
+Constructor creates a smart pointer initialized with \arg{ptr} and stores 
+\arg{ptr} in the location specified by \arg{ppTie} which must not be 
+{\tt NULL}.
+
+\membersection{wxScopedTiedPtr::\destruct{wxScopedTiedPtr}}\label{wxscopedtiedptrdtor}
+
+\func{}{\destruct{wxScopedTiedPtr}}{\void}
+
+Destructor frees the pointer help by this object and restores the value stored
+at the tied location (as specified in the \helpref{constructor}{wxscopedtiedptrctor})
+to the old value.
+
+Warning: this location may now contain an uninitialized value if it hadn't been
+initialized previously, in particular don't count on it magically being 
+{\tt NULL}!
+
+

diff --git a/include/wx/ptr_scpd.h b/include/wx/ptr_scpd.h
index ff287cfad48d64845a6d58def84fd408e62d4baa..d0a24daec3bbfed9e1fb7227c9d807ef4e5c881e 100644 (file)
--- a/include/wx/ptr_scpd.h
+++ b/include/wx/ptr_scpd.h
@@ -182,5 +182,32 @@ void name::reset(T * p){                \
     }                                   \
 }
 
     }                                   \
 }
 

+// ----------------------------------------------------------------------------
+// "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_POINTER__
 
 #endif // __WX_SCOPED_POINTER__