/////////////////////////////////////////////////////////////////////////////
// This class closely follows the implementation of the boost
-// library scoped_ptr and is an adaption for c++ macro's in
-// the wxWindows project. The original authors of the boost
+// library scoped_ptr and is an adaption 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.
#include "wx/defs.h"
-/* checked deleters are used to make sure that the
- type being deleted is really a complete type.
- - Jesse Lovelace <jllovela@eos.ncsu.edu>
-*/
+// ----------------------------------------------------------------------------
+// wxScopedPtr: A scoped pointer
+// ----------------------------------------------------------------------------
-#define wxCHECKED_DELETE(ptr) \
- if (true) { \
- typedef char complete[sizeof(*ptr)]; \
- delete ptr; \
+template <class T>
+class wxScopedPtr
+{
+private:
+ T * m_ptr;
+
+ wxScopedPtr(wxScopedPtr const &);
+ wxScopedPtr & operator=(wxScopedPtr const &);
+
+public:
+ typedef T element_type;
+
+ wxEXPLICIT wxScopedPtr(T * ptr = NULL)
+ : m_ptr(ptr) { }
+
+ ~wxScopedPtr()
+ {
+ if (m_ptr)
+ delete m_ptr;
}
-
-#define wxCHECKED_DELETE_ARRAY(ptr) \
- if (true) { \
- typedef char complete[sizeof(*ptr)]; \
- delete [] 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;
}
-/* These scoped pointers are *not* assignable and cannot be used
- within a container. Look for wxDECLARE_SHARED_PTR for this
- functionality.
+ void reset(T * ptr = NULL)
+ {
+ if (m_ptr != ptr)
+ {
+ 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 & ot)
+ {
+ T * tmp = ot.m_ptr;
+ ot.m_ptr = m_ptr;
+ m_ptr = tmp;
+ }
+};
+
+// ----------------------------------------------------------------------------
+// old macro based implementation
+// ----------------------------------------------------------------------------
- In addition, 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.
+/*
+ checked deleters are used to make sure that the type being deleted is really
+ a complete type.: otherwise sizeof() would result in a compile-time error
+
+ do { ... } while ( 0 ) construct is used to have an anonymous scope
+ (otherwise we could have name clashes between different "complete"s) but
+ still force a semicolon after the macro
*/
+#ifdef __WATCOMC__
+ #define wxFOR_ONCE(name) for(int name=0; name<1; name++)
+ #define wxPRE_NO_WARNING_SCOPE(name) wxFOR_ONCE(wxMAKE_UNIQUE_NAME(name))
+ #define wxPOST_NO_WARNING_SCOPE(name)
+#else
+ #define wxPRE_NO_WARNING_SCOPE(name) do
+ #define wxPOST_NO_WARNING_SCOPE(name) while ( wxFalse )
+#endif
+
+#define wxCHECKED_DELETE(ptr) \
+ wxPRE_NO_WARNING_SCOPE(scope_var1) \
+ { \
+ typedef char complete[sizeof(*ptr)]; \
+ delete ptr; \
+ } wxPOST_NO_WARNING_SCOPE(scope_var1)
+
+#define wxCHECKED_DELETE_ARRAY(ptr) \
+ wxPRE_NO_WARNING_SCOPE(scope_var2) \
+ { \
+ typedef char complete[sizeof(*ptr)]; \
+ delete [] ptr; \
+ } wxPOST_NO_WARNING_SCOPE(scope_var2)
+
+/* 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 \
#define wxDEFINE_SCOPED_PTR(T, name)\
name::~name() \
{ \
- wxCHECKED_DELETE(m_ptr) \
+ 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)
+
+// the same but for arrays instead of simple pointers
#define wxDECLARE_SCOPED_ARRAY(T, name)\
class name \
{ \
};
#define wxDEFINE_SCOPED_ARRAY(T, name) \
-name::~name() \
-{ \
- wxCHECKED_DELETE_ARRAY(m_ptr) \
-} \
-void name::reset(T * p){ \
- if (m_ptr != p) \
- { \
- wxCHECKED_DELETE_ARRAY(m_ptr); \
- m_ptr = p; \
- } \
+name::~name() \
+{ \
+ wxCHECKED_DELETE_ARRAY(m_ptr); \
+} \
+void name::reset(T * p){ \
+ if (m_ptr != p) \
+ { \
+ wxCHECKED_DELETE_ARRAY(m_ptr); \
+ m_ptr = p; \
+ } \
}
-#endif
+// ----------------------------------------------------------------------------
+// "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__
+