]> git.saurik.com Git - wxWidgets.git/blobdiff - include/wx/ptr_scpd.h
MSVC 5 fix.
[wxWidgets.git] / include / wx / ptr_scpd.h
index b574491359fbcdfe7e245f6a23640d107b2facf0..d0a24daec3bbfed9e1fb7227c9d807ef4e5c881e 100644 (file)
 
 #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
@@ -68,7 +74,7 @@ private:                            \
     name & operator=(name const &); \
                                     \
 public:                             \
-    wxEXPLICIT name(T * ptr = NULL)  \
+    wxEXPLICIT name(T * ptr = NULL) \
     : m_ptr(ptr) { }                \
                                     \
     ~name();                        \
@@ -82,6 +88,13 @@ public:                             \
         }                           \
     }                               \
                                     \
+    T *release()                    \
+    {                               \
+        T *ptr = m_ptr;             \
+        m_ptr = NULL;               \
+        return ptr;                 \
+    }                               \
+                                    \
     T & operator*() const           \
     {                               \
         wxASSERT(m_ptr != NULL);    \
@@ -110,9 +123,17 @@ 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                          \
 {                                   \
@@ -149,16 +170,44 @@ 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__
+