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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   7  Redistribution   and   use  in  source  and  binary  forms,  with  or  without
   8  modification, are permitted provided that the following conditions are met:
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  10    * Redistributions  of  source  code  must retain the above copyright notice,
  11      this list of conditions and the following disclaimer.
  12    * Redistributions  in binary form must reproduce the above copyright notice,
  13      this  list of conditions and the following disclaimer in the documentation
  14      and/or other materials provided with the distribution.
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  16  THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  17  AND  ANY  EXPRESS  OR  IMPLIED  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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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 <Moof/Hash.hh>
  42 #include <string>
  43
  44 namespace Mf {
  45
  46
  47 template <class T>
  48 class Mippleton
  49 {
  50         typedef std::pair<unsigned,T*>                                                          ptr_value_t;
  51         typedef std::pair<std::string,ptr_value_t>                                      ptr_map_pair_t;
  52         typedef stlplus::hash<std::string,ptr_value_t,hash_string>      ptr_map_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) :
  60                 name_(name) {}
  61
  62         inline const std::string& getName() const
  63         {
  64                 return name_;
  65         }
  66
  67         inline static T* retain(const std::string& name)
  68         {
  69                 typename ptr_map_t::iterator it = ptrs_.find(name);
  70
  71                 if (it != ptrs_.end())
  72                 {
  73                         ++((*it).second.first);
  74                         return (*it).second.second;
  75                 }
  76                 else
  77                 {
  78                         T* newObj = new T(name);
  79                         ptrs_.insert(ptr_map_pair_t(name, ptr_value_t(1, newObj)));
  80                         return newObj;
  81                 }
  82         }
  83
  84         inline static void releaseByName(const std::string& name)
  85         {
  86                 typename ptr_map_t::iterator it;
  87
  88                 if ((it = ptrs_.find(name)) != ptrs_.end() && --(*it).second.first == 0)
  89                 {
  90                         delete (*it).second.second;
  91                         ptrs_.erase((*it).first);
  92                 }
  93         }
  94
  95         inline static void release(T* obj)
  96         {
  97                 releaseByName(obj->getName());
  98         }
  99 };
 100
 101 template <class T>
 102 stlplus::hash< std::string,std::pair<unsigned,T*>,hash_string >
 103 //std::map< std::string,std::pair<unsigned,T*> >
 104         Mippleton<T>::ptrs_;
 105
 106
 107 } // namespace Mf
 108
 109 #endif // _MOOF_MIPPLETON_HH_
 110
 111 /** vim: set ts=4 sw=4 tw=80: *************************************************/
 112