Keychain/Refs.h

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18 #if 0
  19 //
  20 // Refs.h
  21 //
  22 #ifndef _H_REFS
  23 #define _H_REFS
  24
  25 #include <Security/handleobject.h>
  26 #include <set>
  27
  28 namespace Security
  29 {
  30
  31 namespace KeychainCore
  32 {
  33
  34 class ReferencedObject : public RefCount
  35 {
  36 public:
  37         ReferencedObject() : mHandle(0) {}
  38         virtual ~ReferencedObject() {}
  39
  40     void addedRef(CSSM_HANDLE handle) { mHandle = handle; }
  41     void removedRef(CSSM_HANDLE handle) { mHandle = 0; }
  42     CSSM_HANDLE handle() const { return mHandle; }
  43
  44     void killRef();
  45
  46 private:
  47     CSSM_HANDLE mHandle;
  48 };
  49
  50
  51 class RefObject : public HandleObject, public RefCount
  52 {
  53 public:
  54     RefObject(ReferencedObject &object) : mObject(&object)
  55         {
  56                 if (mObject)
  57                         mObject->addedRef(reinterpret_cast<CSSM_HANDLE>(HandleObject::handle()));
  58         }
  59
  60         void ref() const { RefCount::ref(); }
  61         unsigned int unref() const { return RefCount::unref(); }
  62
  63     RefPointer<ReferencedObject> mObject;
  64 };
  65
  66
  67 inline void ReferencedObject::killRef()
  68 {
  69         delete &killHandle<RefObject>(mHandle);
  70         mHandle = 0;
  71 }
  72
  73
  74 template <class _Object, class _ObjectImpl, class _Handle, OSStatus _ErrorCode>
  75 class Ref
  76 {
  77 public:
  78     static _Handle handle(const _Object &object)
  79         {
  80                 if (!object)
  81                         return 0;
  82
  83                 _Handle handle = reinterpret_cast<_Handle>(object->handle()); // Return the existing handle if it exists
  84                 if (handle)
  85                 {
  86                         retain(handle);
  87                         return handle;
  88                 }
  89
  90                 RefObject *ref = new RefObject(*object);
  91                 ref->ref();
  92                 return reinterpret_cast<_Handle>(ref->HandleObject::handle());
  93         }
  94
  95     static void retain(_Handle handle)
  96     { findHandle<RefObject>(CSSM_HANDLE(handle), _ErrorCode).ref(); }
  97
  98     static void release(_Handle handle)
  99     {
 100                 RefObject &ref = findHandle<RefObject>(CSSM_HANDLE(handle), _ErrorCode);
 101         if (ref.unref() == 0)
 102         {
 103                         if (ref.mObject)
 104                                 ref.mObject->removedRef(CSSM_HANDLE(handle));
 105
 106                         delete &killHandle<RefObject>(CSSM_HANDLE(handle), _ErrorCode);
 107         }
 108     }
 109
 110         static _Object required(_Handle handle)
 111     {
 112                 RefObject &ref = findHandle<RefObject>(CSSM_HANDLE(handle), _ErrorCode);
 113                 if (!ref.mObject)
 114                         MacOSError::throwMe(_ErrorCode);
 115                 _ObjectImpl *impl = dynamic_cast<_ObjectImpl *>(&(*ref.mObject));
 116                 if (!impl)
 117                         MacOSError::throwMe(_ErrorCode);
 118                 return _Object(impl);
 119         }
 120 };
 121
 122 }; // end namespace KeychainCore
 123
 124 } // end namespace Security
 125
 126 #endif // _H_REFS
 127 #endif