]> git.saurik.com Git - wxWidgets.git/blobdiff - include/wx/ptr_scpd.h
don't deprecate the entire wxDrawObject class, this results in warnings when we just...
[wxWidgets.git] / include / wx / ptr_scpd.h
index 79ed8f3f00948ec3c61d4fc1c3c96df287aed471..2ae40220c97f492b461c9e6ec8f7b0441c7708c7 100644 (file)
@@ -10,8 +10,8 @@
 /////////////////////////////////////////////////////////////////////////////
 
 //  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                          \
@@ -117,9 +204,17 @@ public:                             \
 #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                          \
 {                                   \
@@ -156,16 +251,44 @@ public:                             \
 };
 
 #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__
+