Dogcows Code - chaz/yoink/blob - src/Moof/Mippleton.hh

   1
   2 /*******************************************************************************
   3
   4  Copyright (c) 2009, Charles McGarvey
   5  All rights reserved.
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   8  modification, are permitted provided that the following conditions are met:
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  11      this list of conditions and the following disclaimer.
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  13      this  list of conditions and the following disclaimer in the documentation
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  16  THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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  27 *******************************************************************************/
  28
  29 #ifndef _MOOF_MIPPLETON_HH_
  30 #define _MOOF_MIPPLETON_HH_
  31
  32 /**
  33  * @file Mippleton.hh
  34  * Related to singletons, a mippleton is an object which can be obtained
  35  * globally using a unique name.  Unlike singletons, there can be multiple
  36  * mippletons per class, each with a different name or identifier.  Mippletons
  37  * are create automatically when they are first requested (retained) and deleted
  38  * after the last interested code releases its hold on the object.
  39  */
  40
  41 #include <map>
  42 #include <string>
  43
  44
  45 namespace Mf {
  46
  47
  48 template <class T>
  49 class Mippleton
  50 {
  51         typedef std::pair<unsigned,T*>                          ptr_value_t;
  52         typedef std::pair<std::string,ptr_value_t>      ptr_map_pair_t;
  53         typedef std::map<std::string,ptr_value_t>       ptr_map_t;
  54
  55         static ptr_map_t ptrs_;
  56         std::string name_;
  57
  58 public:
  59         explicit Mippleton(const std::string& name) : name_(name) {}
  60
  61         inline const std::string& getName() const
  62         {
  63                 return name_;
  64         }
  65
  66         inline static T* retain(const std::string& name)
  67         {
  68                 typename ptr_map_t::iterator it;
  69
  70                 if ((it = ptrs_.find(name)) != ptrs_.end())
  71                 {
  72                         (*it).second.first++;
  73                         return (*it).second.second;
  74                 }
  75                 else
  76                 {
  77                         T* newObj = new T(name);
  78                         ptrs_.insert(ptr_map_pair_t(name, ptr_value_t(1, newObj)));
  79                         return newObj;
  80                 }
  81         }
  82
  83         inline static void releaseByName(const std::string& name)
  84         {
  85                 typename ptr_map_t::iterator it;
  86
  87                 if ((it = ptrs_.find(name)) != ptrs_.end() && -(*it).second.first == 0)
  88                 {
  89                         delete (*it).second.second;
  90                         ptrs_.erase(it);
  91                 }
  92         }
  93
  94         inline static void release(T* obj)
  95         {
  96                 releaseByName(obj->getName());
  97         }
  98 };
  99
 100 template <class T>
 101 std::map<std::string,std::pair<unsigned,T*> > Mippleton<T>::ptrs_;
 102
 103
 104 } // namespace Mf
 105
 106 #endif // _MOOF_MIPPLETON_HH_
 107
 108 /** vim: set ts=4 sw=4 tw=80: *************************************************/
 109