+/////////////////////////////////////////////////////////////////////////////
+// Name: wx/mac/corefoundation/cfref.h
+// Purpose: wxCFRef template class
+// Author: David Elliott <dfe@cox.net>
+// Modified by: Stefan Csomor
+// Created: 2007/05/10
+// RCS-ID: $Id$
+// Copyright: (c) 2007 David Elliott <dfe@cox.net>, Stefan Csomor
+// Licence: wxWindows licence
+// Notes: See http://developer.apple.com/documentation/CoreFoundation/Conceptual/CFMemoryMgmt/index.html
+/////////////////////////////////////////////////////////////////////////////
+/*! @header wx/mac/corefoundation/cfref.h
+ @abstract wxCFRef template class
+ @discussion FIXME: Convert doc tags to something less buggy with C++
+*/
+
+#ifndef _WX_MAC_COREFOUNDATION_CFREF_H__
+#define _WX_MAC_COREFOUNDATION_CFREF_H__
+
+// Include unistd to ensure that NULL is defined
+#include <unistd.h>
+// Include AvailabilityMacros for DEPRECATED_ATTRIBUTE
+#include <AvailabilityMacros.h>
+
+// #include <CoreFoundation/CFBase.h>
+/* Don't include CFBase.h such that this header can be included from public
+ * headers with minimal namespace pollution.
+ * Note that Darwin CF uses extern for CF_EXPORT. If we need this on Win32
+ * or non-Darwin Mac OS we'll need to define the appropriate __declspec.
+ */
+typedef const void *CFTypeRef;
+extern "C" {
+extern /* CF_EXPORT */
+CFTypeRef CFRetain(CFTypeRef cf);
+extern /* CF_EXPORT */
+void CFRelease(CFTypeRef cf);
+} // extern "C"
+
+
+/*! @function wxCFRelease
+ @abstract A CFRelease variant that checks for NULL before releasing.
+ @discussion The parameter is template not for type safety but to ensure the argument
+ is a raw pointer and not a ref holder of any type.
+*/
+template <class Type>
+inline void wxCFRelease(Type *r)
+{
+ if ( r != NULL )
+ ::CFRelease((CFTypeRef)r);
+}
+
+/*! @function wxCFRetain
+ @abstract A typesafe CFRetain variant that checks for NULL.
+*/
+template <class Type>
+inline Type* wxCFRetain(Type *r)
+{
+ // NOTE(DE): Setting r to the result of CFRetain improves efficiency on both x86 and PPC
+ // Casting r to CFTypeRef ensures we are calling the real C version defined in CFBase.h
+ // and not any possibly templated/overloaded CFRetain.
+ if ( r != NULL )
+ r = (Type*)::CFRetain((CFTypeRef)r);
+ return r;
+}
+
+template <class refType>
+class wxCFRef;
+
+/*! @class wxCFWeakRef
+ @templatefield refType The CF reference type (e.g. CFStringRef, CFRunLoopRef, etc.)
+ It should already be a pointer. This is different from
+ shared_ptr where the template parameter is the pointee type.
+ @discussion Wraps a raw pointer without any retain or release.
+ Provides a way to get what amounts to a raw pointer from a wxCFRef without
+ using a raw pointer. Unlike a raw pointer, constructing a wxCFRef from this
+ class will cause it to be retained because it is assumed that a wxCFWeakRef
+ does not own its pointer.
+*/
+template <class refType>
+class wxCFWeakRef
+{
+ template <class refTypeA, class otherRefType>
+ friend wxCFWeakRef<refTypeA> static_cfref_cast(const wxCFRef<otherRefType> &otherRef);
+public:
+ /*! @method wxCFWeakRef
+ @abstract Creates a NULL reference
+ */
+ wxCFWeakRef()
+ : m_ptr(NULL)
+ {}
+
+ // Default copy constructor is fine.
+ // Default destructor is fine but we'll set NULL to avoid bugs
+ ~wxCFWeakRef()
+ { m_ptr = NULL; }
+
+ // Do not implement a raw-pointer constructor.
+
+ /*! @method wxCFWeakRef
+ @abstract Copies another ref holder where its type can be converted to ours
+ @templatefield otherRefType Any type held by another wxCFWeakRef.
+ @param otherRef The other weak ref holder to copy.
+ @discussion This is merely a copy or implicit cast.
+ */
+ template <class otherRefType>
+ wxCFWeakRef(const wxCFWeakRef<otherRefType>& otherRef)
+ : m_ptr(otherRef.get()) // Implicit conversion from otherRefType to refType should occur
+ {}
+
+ /*! @method wxCFWeakRef
+ @abstract Copies a strong ref holder where its type can be converted to ours
+ @templatefield otherRefType Any type held by a wxCFRef.
+ @param otherRef The strong ref holder to copy.
+ @discussion This ref is merely a pointer copy, the strong ref still holds the pointer.
+ */
+ template <class otherRefType>
+ wxCFWeakRef(const wxCFRef<otherRefType>& otherRef)
+ : m_ptr(otherRef.get()) // Implicit conversion from otherRefType to refType should occur
+ {}
+
+ /*! @method get
+ @abstract Explicit conversion to the underlying pointer type
+ @discussion Allows the caller to explicitly get the underlying pointer.
+ */
+ refType get() const
+ { return m_ptr; }
+
+ /*! @method operator refType
+ @abstract Implicit conversion to the underlying pointer type
+ @discussion Allows the ref to be used in CF function calls.
+ */
+ operator refType() const
+ { return m_ptr; }
+
+protected:
+ /*! @method wxCFWeakRef
+ @abstract Constructs a weak reference to the raw pointer
+ @templatefield otherType Any type.
+ @param p The raw pointer to assume ownership of. May be NULL.
+ @discussion This method is private so that the friend static_cfref_cast can use it
+ */
+ template <class otherType>
+ explicit wxCFWeakRef(otherType *p)
+ : m_ptr(p) // Implicit conversion from otherType* to refType should occur.
+ {}
+
+ /*! @var m_ptr The raw pointer.
+ */
+ refType m_ptr;
+};
+
+/*! @class wxCFRef
+ @templatefield refType The CF reference type (e.g. CFStringRef, CFRunLoopRef, etc.)
+ It should already be a pointer. This is different from
+ shared_ptr where the template parameter is the pointee type.
+ @discussion Properly retains/releases reference to CoreFoundation objects
+*/
+template <class refType>
+class wxCFRef
+{
+public:
+ /*! @method wxCFRef
+ @abstract Creates a NULL reference
+ */
+ wxCFRef()
+ : m_ptr(NULL)
+ {}
+
+ /*! @method wxCFRef
+ @abstract Assumes ownership of p and creates a reference to it.
+ @templatefield otherType Any type.
+ @param p The raw pointer to assume ownership of. May be NULL.
+ @discussion Like shared_ptr, it is assumed that the caller has a strong reference to p and intends
+ to transfer ownership of that reference to this ref holder. If the object comes from
+ a Create or Copy method then this is the correct behavior. If the object comes from
+ a Get method then you must CFRetain it yourself before passing it to this constructor.
+ A handy way to do this is to use the non-member wxCFRefFromGet factory funcion.
+ This method is templated and takes an otherType *p. This prevents implicit conversion
+ using an operator refType() in a different ref-holding class type.
+ */
+ template <class otherType>
+ explicit wxCFRef(otherType *p)
+ : m_ptr(p) // Implicit conversion from otherType* to refType should occur.
+ {}
+
+ /*! @method wxCFRef
+ @abstract Copies a ref holder of the same type
+ @param otherRef The other ref holder to copy.
+ @discussion Ownership will be shared by the original ref and the newly created ref. That is,
+ the object will be explicitly retained by this new ref.
+ */
+ wxCFRef(const wxCFRef& otherRef)
+ : m_ptr(wxCFRetain(otherRef.m_ptr))
+ {}
+
+ /*! @method wxCFRef
+ @abstract Copies a ref holder where its type can be converted to ours
+ @templatefield otherRefType Any type held by another wxCFRef.
+ @param otherRef The other ref holder to copy.
+ @discussion Ownership will be shared by the original ref and the newly created ref. That is,
+ the object will be explicitly retained by this new ref.
+ */
+ template <class otherRefType>
+ wxCFRef(const wxCFRef<otherRefType>& otherRef)
+ : m_ptr(wxCFRetain(otherRef.get())) // Implicit conversion from otherRefType to refType should occur
+ {}
+
+ /*! @method wxCFRef
+ @abstract Copies a weak ref holder where its type can be converted to ours
+ @templatefield otherRefType Any type held by a wxCFWeakRef.
+ @param otherRef The weak ref holder to copy.
+ @discussion Ownership will be taken by this newly created ref. That is,
+ the object will be explicitly retained by this new ref.
+ Ownership is most likely shared with some other ref as well.
+ */
+ template <class otherRefType>
+ wxCFRef(const wxCFWeakRef<otherRefType>& otherRef)
+ : m_ptr(wxCFRetain(otherRef.get())) // Implicit conversion from otherRefType to refType should occur
+ {}
+
+ /*! @method ~wxCFRef
+ @abstract Releases (potentially shared) ownership of the ref.
+ @discussion A ref holder instance is always assumed to have ownership so ownership is always
+ released (CFRelease called) upon destruction.
+ */
+ ~wxCFRef()
+ { reset(); }
+
+ /*! @method operator=
+ @abstract Assigns the other ref's pointer to us when the otherRef is the same type.
+ @param otherRef The other ref holder to copy.
+ @discussion The incoming pointer is retained, the original pointer is released, and this object
+ is made to point to the new pointer.
+ */
+ wxCFRef& operator=(const wxCFRef& otherRef)
+ {
+ wxCFRetain(otherRef.m_ptr);
+ wxCFRelease(m_ptr);
+ m_ptr = otherRef.m_ptr;
+ return *this;
+ }
+
+ /*! @method operator=
+ @abstract Assigns the other ref's pointer to us when the other ref can be converted to our type.
+ @templatefield otherRefType Any type held by another wxCFRef
+ @param otherRef The other ref holder to copy.
+ @discussion The incoming pointer is retained, the original pointer is released, and this object
+ is made to point to the new pointer.
+ */
+ template <class otherRefType>
+ wxCFRef& operator=(const wxCFRef<otherRefType>& otherRef)
+ {
+ wxCFRetain(otherRef.get());
+ wxCFRelease(m_ptr);
+ m_ptr = otherRef.get(); // Implicit conversion from otherRefType to refType should occur
+ return *this;
+ }
+
+ /*! @method get
+ @abstract Explicit conversion to the underlying pointer type
+ @discussion Allows the caller to explicitly get the underlying pointer.
+ */
+ refType get() const
+ { return m_ptr; }
+
+ /*! @method operator refType
+ @abstract Implicit conversion to the underlying pointer type
+ @discussion Allows the ref to be used in CF function calls.
+ */
+ operator refType() const
+ { return m_ptr; }
+
+#if 0
+ < // HeaderDoc is retarded and thinks the GT from operator-> is part of a template param.
+ // So give it that < outside of a comment to fake it out. (if 0 is not a comment to HeaderDoc)
+#endif
+
+ /*! @method operator->
+ @abstract Implicit conversion to the underlying pointer type
+ @discussion This is nearly useless for CF types which are nearly always opaque
+ */
+ refType operator-> () const
+ { return m_ptr; }
+
+ /*! @method reset
+ @abstract Nullifies the reference
+ @discussion Releases ownership (calls CFRelease) before nullifying the pointer.
+ */
+ void reset()
+ {
+ wxCFRelease(m_ptr);
+ m_ptr = NULL;
+ }
+
+ /*! @method reset
+ @abstract Sets this to a new reference
+ @templatefield otherType Any type.
+ @param p The raw pointer to assume ownership of
+ @discussion The existing reference is released (like destruction). It is assumed that the caller
+ has a strong reference to the new p and intends to transfer ownership of that reference
+ to this ref holder. Take care to call CFRetain if you received the object from a Get method.
+ This method is templated and takes an otherType *p. This prevents implicit conversion
+ using an operator refType() in a different ref-holding class type.
+ */
+ template <class otherType>
+ void reset(otherType* p)
+ {
+ wxCFRelease(m_ptr);
+ m_ptr = p; // Automatic conversion should occur
+ }
+protected:
+ /*! @var m_ptr The raw pointer.
+ */
+ refType m_ptr;
+};
+
+/*! @function wxCFRefFromGet
+ @abstract Factory function to create wxCFRef from a raw pointer obtained from a Get-rule function
+ @param p The pointer to retain and create a wxCFRef from. May be NULL.
+ @discussion Unlike the wxCFRef raw pointer constructor, this function explicitly retains its
+ argument. This can be used for functions such as CFDictionaryGetValue() or
+ CFAttributedStringGetString() which return a temporary reference (Get-rule functions).
+ FIXME: Anybody got a better name?
+*/
+template <typename Type>
+inline wxCFRef<Type*> wxCFRefFromGet(Type *p)
+{
+ return wxCFRef<Type*>(wxCFRetain(p));
+}
+
+/*! @function static_cfref_cast
+ @abstract Works like static_cast but with a wxCFRef as the argument.
+ @param refType Template parameter. The destination raw pointer type
+ @param otherRef Normal parameter. The source wxCFRef<> object.
+ @discussion This is intended to be a clever way to make static_cast work while allowing
+ the return value to be converted to either a strong ref or a raw pointer
+ while ensuring that the retain count is updated appropriately.
+
+ This is modeled after shared_ptr's static_pointer_cast. Just as wxCFRef is
+ parameterized on a pointer to an opaque type so is this class. Note that
+ this differs from shared_ptr which is parameterized on the pointee type.
+
+ FIXME: Anybody got a better name?
+*/
+template <class refType, class otherRefType>
+inline wxCFWeakRef<refType> static_cfref_cast(const wxCFRef<otherRefType> &otherRef);
+
+template <class refType, class otherRefType>
+inline wxCFWeakRef<refType> static_cfref_cast(const wxCFRef<otherRefType> &otherRef)
+{
+ return wxCFWeakRef<refType>(static_cast<refType>(otherRef.get()));
+}
+
+/*! @function CFRelease
+ @abstract Overloads CFRelease so that the user is warned of bad behavior.
+ @discussion It is rarely appropriate to retain or release a wxCFRef. If one absolutely
+ must do it he can explicitly get() the raw pointer
+ Normally, this function is unimplemented resulting in a linker error if used.
+*/
+template <class T>
+inline void CFRelease(const wxCFRef<T*> & cfref) DEPRECATED_ATTRIBUTE;
+
+/*! @function CFRetain
+ @abstract Overloads CFRetain so that the user is warned of bad behavior.
+ @discussion It is rarely appropriate to retain or release a wxCFRef. If one absolutely
+ must do it he can explicitly get() the raw pointer
+ Normally, this function is unimplemented resulting in a linker error if used.
+*/
+template <class T>
+inline void CFRetain(const wxCFRef<T*>& cfref) DEPRECATED_ATTRIBUTE;
+
+// Change the 0 to a 1 if you want the functions to work (no link errors)
+// Neither function will cause retain/release side-effects if implemented.
+#if 0
+template <class T>
+void CFRelease(const wxCFRef<T*> & cfref)
+{
+ CFRelease(cfref.get());
+}
+
+template <class T>
+void CFRetain(const wxCFRef<T*> & cfref)
+{
+ CFRetain(cfref.get());
+}
+#endif
+
+#endif //ndef _WX_MAC_COREFOUNDATION_CFREF_H__
+