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/* ------------------------------------------------------------------------
* $Id: Guard.hh,v 1.3 2001/06/29 15:00:38 elm Exp $
*
* This file is part of 3Dwm: The Three-Dimensional User Environment.
*
* 3Dwm: The Three-Dimensional User Environment:
* <http://www.3dwm.org>
*
* Chalmers Medialab
* <http://www.medialab.chalmers.se>
*
* ------------------------------------------------------------------------
* File created 2001-04-29 by Niklas Elmqvist.
*
* Copyright (c) 2001 Niklas Elmqvist <elm@3dwm.org>.
* ------------------------------------------------------------------------
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
* ------------------------------------------------------------------------
*/
#ifndef _Guard_hh_
#define _Guard_hh_
// -- Class Declarations
/**
* Guard template class used for enforcing mutual exclusion of
* critical areas in a code segment. This class is designed to use any
* class that supports the lock()/unlock() methods to effect mutual
* exclusion in the scope of the Guard object.
**/
template <class T>
class Guard {
public:
/**
* Constructor. This will lock the passed mutex or semaphore.
*
* @param t entity to use to protect the section.
**/
Guard(T &t) : _t(t) {
_t.lock();
}
/**
* Destructor. This will unlock the mutual exclusion entity (from
* before).
**/
~Guard() {
_t.unlock();
}
private:
Guard(const Guard<T> &s);
Guard &operator = (const Guard &);
T &_t;
};
#endif /* Guard.hh */
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