Menes/ObjectHandle.h

   1 /* Cydia - iPhone UIKit Front-End for Debian APT
   2  * Copyright (C) 2008-2011  Jay Freeman (saurik)
   3 */
   4
   5 /* Modified BSD License {{{ */
   6 /*
   7  *        Redistribution and use in source and binary
   8  * forms, with or without modification, are permitted
   9  * provided that the following conditions are met:
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  11  * 1. Redistributions of source code must retain the
  12  *    above copyright notice, this list of conditions
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  15  *    above copyright notice, this list of conditions
  16  *    and the following disclaimer in the documentation
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  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS''
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  37 */
  38 /* }}} */
  39
  40 #ifndef Menes_ObjectHandle_H
  41 #define Menes_ObjectHandle_H
  42
  43 template <typename Type_, unsigned Delegate_>
  44 struct MenesObjectHandle_;
  45
  46 template <typename Type_>
  47 struct MenesObjectHandle_<Type_, 0> {
  48     static _finline void Execute(Type_ *value) {
  49     }
  50 };
  51
  52 template <typename Type_>
  53 struct MenesObjectHandle_<Type_, 1> {
  54     static _finline void Execute(Type_ *value) {
  55         [value setDelegate:nil];
  56     }
  57 };
  58
  59 template <typename Type_>
  60 struct MenesObjectHandle_<Type_, 2> {
  61     static _finline void Execute(Type_ *value) {
  62         [value setDelegate:nil];
  63         [value setDataSource:nil];
  64     }
  65 };
  66
  67 template <typename Type_, unsigned Delegate_ = 0>
  68 class MenesObjectHandle {
  69   private:
  70     Type_ *value_;
  71
  72     _finline void Retain_() {
  73         if (value_ != nil)
  74             CFRetain((CFTypeRef) value_);
  75     }
  76
  77     _finline void Clear_() {
  78         if (value_ != nil) {
  79             MenesObjectHandle_<Type_, Delegate_>::Execute(value_);
  80             CFRelease((CFTypeRef) value_);
  81         }
  82     }
  83
  84   public:
  85     _finline MenesObjectHandle(const MenesObjectHandle &rhs) :
  86         value_(rhs.value_ == nil ? nil : (Type_ *) CFRetain((CFTypeRef) rhs.value_))
  87     {
  88     }
  89
  90     _finline MenesObjectHandle(Type_ *value = NULL, bool mended = false) :
  91         value_(value)
  92     {
  93         if (!mended)
  94             Retain_();
  95     }
  96
  97     _finline ~MenesObjectHandle() {
  98         Clear_();
  99     }
 100
 101     _finline operator Type_ *() const {
 102         return value_;
 103     }
 104
 105     _finline MenesObjectHandle &operator =(Type_ *value) {
 106         if (value_ != value) {
 107             Type_ *old(value_);
 108             value_ = value;
 109             Retain_();
 110             if (old != nil)
 111                 CFRelease((CFTypeRef) old);
 112         } return *this;
 113     }
 114
 115     _finline MenesObjectHandle &operator =(const MenesObjectHandle &value) {
 116         return this->operator =(value.operator Type_ *());
 117     }
 118 };
 119
 120 #define _H MenesObjectHandle
 121
 122 #endif//Menes_ObjectHandle_H