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/* This file is part of indexlib.
* Copyright (C) 2005 Luís Pedro Coelho <luis@luispedro.org>
*
* 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 Qt library by Trolltech AS, Norway (or with modified versions
* of Qt that use the same license as Qt), 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
* Qt. 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 "lockfile.h"
#include "format.h"
#include "logfile.h"
#include <iostream>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
using indexlib::detail::lockfile;
lockfile::lockfile( std::string filename ):
filename_( filename ),
locked_( false ) {
}
lockfile::~lockfile() {
if ( locked() ) unlock();
}
bool lockfile::locked() const {
return locked_;
}
bool lockfile::trylock() {
int fd = ::open( filename_.c_str(), O_RDWR | O_EXCL | O_CREAT, 0600 );
locked_ = false;
if ( fd >= 0 ) {
locked_ = true;
close( fd );
}
logfile() << format( "trylock(%s) returning %s (fd:%s) (error:%s)\n" ) % filename_ % locked_ %fd % strerror( errno );
return locked_;
}
void lockfile::unlock() {
if ( locked() ) {
unlink( filename_.c_str() );
locked_ = false;
}
}
void lockfile::force_unlock() {
unlink( filename_.c_str() );
locked_ = false;
}
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