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salome-smesh  6.5.0
ObjectPool.hxx
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00001 // Copyright (C) 2010-2012  CEA/DEN, EDF R&D, OPEN CASCADE
00002 //
00003 // This library is free software; you can redistribute it and/or
00004 // modify it under the terms of the GNU Lesser General Public
00005 // License as published by the Free Software Foundation; either
00006 // version 2.1 of the License.
00007 //
00008 // This library is distributed in the hope that it will be useful,
00009 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00010 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00011 // Lesser General Public License for more details.
00012 //
00013 // You should have received a copy of the GNU Lesser General Public
00014 // License along with this library; if not, write to the Free Software
00015 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
00016 //
00017 // See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
00018 //
00019 
00020 #ifndef _OBJECTPOOL_HXX_
00021 #define _OBJECTPOOL_HXX_
00022 
00023 #include <vector>
00024 #include <stack>
00025 #include <iostream>
00026 
00027 template<class X> class ObjectPool
00028 {
00029 
00030 private:
00031   std::vector<X*> _chunkList;
00032   std::vector<bool> _freeList;
00033   int _nextFree;
00034   int _maxAvail;
00035   int _chunkSize;
00036 
00037   int getNextFree()
00038   {
00039     for (int i = _nextFree; i < _maxAvail; i++)
00040       if (_freeList[i] == true)
00041         {
00042           return i;
00043           break;
00044         }
00045     return _maxAvail;
00046   }
00047 
00048   void checkDelete(int chunkId)
00049   {
00050     int i0 = _chunkSize * chunkId;
00051     int i1 = _chunkSize * (chunkId + 1);
00052     for (int i = i0; i < i1; i++)
00053       if (_freeList[i] == false)
00054         return;
00055     std::cerr << "a chunk to delete" << std::endl;
00056     // compactage des vecteurs un peu lourd, pas necessaire
00057     //X* chunk = _chunkList[chunkId];
00058     //delete [] chunk;
00059   }
00060 
00061 public:
00062   ObjectPool(int nblk)
00063   {
00064     _chunkSize = nblk;
00065     _nextFree = 0;
00066     _maxAvail = 0;
00067     _chunkList.clear();
00068     _freeList.clear();
00069   }
00070 
00071   virtual ~ObjectPool()
00072   {
00073     for (int i = 0; i < _chunkList.size(); i++)
00074       delete[] _chunkList[i];
00075   }
00076 
00077   X* getNew()
00078   {
00079     X *obj = 0;
00080     _nextFree = getNextFree();
00081     if (_nextFree == _maxAvail)
00082       {
00083         X* newChunk = new X[_chunkSize];
00084         _chunkList.push_back(newChunk);
00085         _freeList.insert(_freeList.end(), _chunkSize, true);
00086         _maxAvail += _chunkSize;
00087         _freeList[_nextFree] = false;
00088         obj = newChunk; // &newChunk[0];
00089       }
00090     else
00091       {
00092         int chunkId = _nextFree / _chunkSize;
00093         int rank = _nextFree - chunkId * _chunkSize;
00094         _freeList[_nextFree] = false;
00095         obj = _chunkList[chunkId] + rank; // &_chunkList[chunkId][rank];
00096       }
00097     //obj->init();
00098     return obj;
00099   }
00100 
00101   void destroy(X* obj)
00102   {
00103     long adrobj = (long) (obj);
00104     for (int i = 0; i < _chunkList.size(); i++)
00105       {
00106         X* chunk = _chunkList[i];
00107         long adrmin = (long) (chunk);
00108         if (adrobj < adrmin)
00109           continue;
00110         long adrmax = (long) (chunk + _chunkSize);
00111         if (adrobj >= adrmax)
00112           continue;
00113         int rank = (adrobj - adrmin) / sizeof(X);
00114         int toFree = i * _chunkSize + rank;
00115         _freeList[toFree] = true;
00116         if (toFree < _nextFree)
00117           _nextFree = toFree;
00118         //obj->clean();
00119         //checkDelete(i); compactage non fait
00120         break;
00121       }
00122   }
00123 
00124   //  void destroy(int toFree)
00125   //  {
00126   //    // no control 0<= toFree < _freeList.size()
00127   //    _freeList[toFree] = true;
00128   //    if (toFree < _nextFree)
00129   //      _nextFree = toFree;
00130   //  }
00131 
00132 };
00133 
00134 #endif