/*
**	PJL C++ Library
**	simple_pool.h
**
**	Copyright (C) 2004  Paul J. Lucas
**
**	This program 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
**	(at your option) 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#ifndef simple_pool_H
#define simple_pool_H

// standard
#include <vector>

namespace PJL {

template< class T > class simple_pool_object;

//*****************************************************************************
//
// SYNOPSYS
//
	template< class T > class simple_pool
//
// DESCRIPTION
//
//	A simple_pool is an object that is used to keep track of dynamically
//	allocated objects derived from simple_pool_object for the purpose of
//	ensuring that they are all deleted when the pool is deleted.  It's a
//	"poor man's garbage collector."
//
//*****************************************************************************
{
public:
	~simple_pool() {
		list_type::const_iterator i;
		for ( i = list_.begin(); i != list_.end(); ++i )
			delete static_cast<T*>( *i );
	}
private:
	typedef std::vector<void*> list_type;
	list_type list_;

	void add( void *obj )			{ list_.push_back( obj ); }

	friend class simple_pool_object<T>;
};

//*****************************************************************************
//
// SYNOPSYS
//
	template< class Derived > class simple_pool_object
//
// DESCRIPTION
//
//	A simple_pool_object is the base class for another that should be
//	"pooled" such that it, and others like it in the same pool, are deleted
//	when the pool is deleted.
//
//*****************************************************************************
{
public:
	typedef simple_pool_object<Derived> pool_object_type;
	typedef simple_pool<Derived> pool_type;

	pool_type& pool() const { return *pool_; }

	virtual ~simple_pool_object() { }
protected:
	simple_pool_object( pool_type *pool = 0 ) : pool_( pool ) {
		if ( pool_ )
			pool_->add( this );
	}
	simple_pool_object( pool_type &pool ) : pool_( &pool ) {
		pool_->add( this );
	}
private:
	pool_type *const pool_;
};

} // namespace PJL

#endif	/* simple_pool_H */
/* vim:set noet sw=8 ts=8: */