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#ifndef LPC_LOCKFILE_H1118420718_INCLUDE_GUARD_
#define LPC_LOCKFILE_H1118420718_INCLUDE_GUARD_
/* This file is part of indexlib.
* Copyright (C) 2005 Luís Pedro Coelho <[email protected]>
*
* Indexlib is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation and available as file
* GPL_V2 which is distributed along with indexlib.
*
* Indexlib 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., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA
*
* In addition, as a special exception, the copyright holders give
* permission to link the code of this program with any edition of
* the TQt library by Trolltech AS, Norway (or with modified versions
* of TQt that use the same license as TQt), and distribute linked
* combinations including the two. You must obey the GNU General
* Public License in all respects for all of the code used other than
* TQt. If you modify this file, you may extend this exception to
* your version of the file, but you are not obligated to do so. If
* you do not wish to do so, delete this exception statement from
* your version.
*/
#include <string>
namespace indexlib { namespace detail {
/**
* Implements a simple, file based lock.
*
* Given a filename, it can be used to ensure that only one such file is in use at the time.
*/
class lockfile {
public:
/** Creates the object, doesn't actually do anything */
explicit lockfile( std::string name );
/** if locked, unlocks */
~lockfile();
/** Returns whether the file is locked */
bool locked() const;
/** Tries to lock the file returning true in case of success */
bool trylock();
/** Unlocks if you own the lock, otherwise it's a nop. */
void unlock();
/** This removes the lock, no matter what. */
void force_unlock();
private:
std::string filename_;
bool locked_;
};
}}
#endif /* LPC_LOCKFILE_H1118420718_INCLUDE_GUARD_ */
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