// 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
+// 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>
+/*
+ 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
*/
-#define wxCHECKED_DELETE(ptr) \
- if (true) { \
- typedef char complete[sizeof(*ptr)]; \
- delete ptr; \
- }
+#define wxCHECKED_DELETE(ptr) \
+ do \
+ { \
+ typedef char complete[sizeof(*ptr)]; \
+ delete ptr; \
+ } while ( 0 )
-#define wxCHECKED_DELETE_ARRAY(ptr) \
- if (true) { \
- typedef char complete[sizeof(*ptr)]; \
- delete [] ptr; \
- }
+#define wxCHECKED_DELETE_ARRAY(ptr) \
+ do \
+ { \
+ typedef char complete[sizeof(*ptr)]; \
+ delete [] ptr; \
+ } while ( 0 )
/* These scoped pointers are *not* assignable and cannot be used
within a container. Look for wxDECLARE_SHARED_PTR for this
#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__
+