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

   1
   2 /*******************************************************************************
   3
   4  Copyright (c) 2009, Charles McGarvey
   5  All rights reserved.
   6
   7  Redistribution   and   use  in  source  and  binary  forms,  with  or  without
   8  modification, are permitted provided that the following conditions are met:
   9
  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.
  15
  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
  18  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  DISCLAIMED.  IN  NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  20  FOR  ANY  DIRECT,  INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  DAMAGES  (INCLUDING,  BUT  NOT  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  SERVICES;  LOSS  OF  USE,  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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  25  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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  27 *******************************************************************************/
  28
  29 #ifndef _MOOF_MANAGER_HH_
  30 #define _MOOF_MANAGER_HH_
  31
  32 /**
  33  * @file Manager.hh
  34  * A library is a collection of named objects of the same type.  Libraries use
  35  * reference counting to automagically delete objects which no longer have any
  36  * interested code.
  37  */
  38
  39 #include <string>
  40
  41 #include <boost/shared_ptr.hpp>
  42
  43 #include <Moof/Hash.hh>
  44
  45
  46 namespace Mf {
  47
  48
  49 template <class T>
  50 class Manager
  51 {
  52 public:
  53
  54         Manager() :
  55                 mRetainCount(1) {}
  56
  57         const std::string& getName() const
  58         {
  59                 return mName;
  60         }
  61
  62         static boost::shared_ptr<T> getInstance(const std::string& name)
  63         {
  64                 return boost::shared_ptr<T>(retain(name), &release);
  65         }
  66
  67 private:
  68
  69         typedef stlplus::hash<std::string,T*,getHash> PtrMap;
  70
  71         static PtrMap   mPtrMap;
  72         std::string             mName;
  73         unsigned                mRetainCount;
  74
  75         static T* retain(const std::string& name)
  76         {
  77                 typename PtrMap::iterator it = mPtrMap.find(name);
  78
  79                 if (it != mPtrMap.end())
  80                 {
  81                         ++((*it).second->mRetainCount);
  82                         return (*it).second;
  83                 }
  84                 else
  85                 {
  86                         T* newObj(new T);
  87                         if (newObj)
  88                         {
  89                                 newObj->mName = name;
  90                                 newObj->init(name);
  91                                 mPtrMap.insert(std::make_pair(name, newObj));
  92                         }
  93                         return newObj;
  94                 }
  95         }
  96
  97         static void release(T* obj)
  98         {
  99                 if (--(obj->mRetainCount) == 0)
 100                 {
 101                         mPtrMap.erase(obj->mName);
 102                         delete obj;
 103                 }
 104         }
 105 };
 106
 107 template <class T>
 108 stlplus::hash<std::string,T*,getHash> Manager<T>::mPtrMap;
 109
 110
 111 } // namespace Mf
 112
 113 #endif // _MOOF_MANAGER_HH_
 114
 115 /** vim: set ts=4 sw=4 tw=80: *************************************************/
 116