mapnik/include/pool.hpp

115 lines
2.8 KiB
C++

/* This file is part of Mapnik (c++ mapping toolkit)
* Copyright (C) 2005 Artem Pavlenko
*
* Mapnik is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
//$Id: pool.hpp 39 2005-04-10 20:39:53Z pavlenko $
#ifndef POOL_HPP
#define POOL_HPP
#include <iostream>
#include <map>
#include <deque>
#include <ctime>
#include "utils.hpp"
#include <boost/shared_ptr.hpp>
#include <boost/thread/mutex.hpp>
#include <boost/utility.hpp>
namespace mapnik
{
template <typename T, typename PoolT>
class PoolGuard
{
private:
const T& obj_;
PoolT& pool_;
public:
explicit PoolGuard(const T& ptr,PoolT& pool)
: obj_(ptr),
pool_(pool) {}
~PoolGuard()
{
pool_->returnObject(obj_);
}
private:
PoolGuard();
PoolGuard(const PoolGuard&);
PoolGuard& operator=(const PoolGuard&);
};
template <typename T,template <typename> class Creator>
class Pool : private boost::noncopyable
{
typedef boost::shared_ptr<T> HolderType;
typedef std::deque<HolderType> ContType;
Creator<T> creator_;
const int initialSize_;
const int maxSize_;
ContType usedPool_;
ContType unusedPool_;
boost::mutex mutex_;
public:
Pool(const Creator<T>& creator,int initialSize=5,int maxSize=20)
:creator_(creator),
initialSize_(initialSize),
maxSize_(maxSize)
{
for (int i=0;i<initialSize_;++i)
{
unusedPool_.push_back(HolderType(creator_()));
}
}
const HolderType& borrowObject()
{
mutex::scoped_lock lock(mutex_);
typename ContType::iterator itr=unusedPool_.begin();
if (itr!=unusedPool_.end())
{
std::clog<<"borrow "<<(*itr).get()<<"\n";
usedPool_.push_back(*itr);
itr=unusedPool_.erase(itr);
return usedPool_[usedPool_.size()-1];
}
static const HolderType defaultObj;
return defaultObj;
}
void returnObject(const HolderType& obj)
{
mutex::scoped_lock lock(mutex_);
typename ContType::iterator itr=usedPool_.begin();
while (itr != usedPool_.end())
{
if (obj.get()==(*itr).get())
{
std::clog<<"return "<<(*itr).get()<<"\n";
unusedPool_.push_back(*itr);
usedPool_.erase(itr);
return;
}
++itr;
}
}
};
}
#endif //POOL_HPP