59 lines
1.6 KiB
Python
59 lines
1.6 KiB
Python
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# -*- coding: utf-8 -*-
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#
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# 2017 Darko Poljak (darko.poljak at gmail.com)
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#
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# This file is part of cdist.
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#
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# cdist is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# cdist is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with cdist. If not, see <http://www.gnu.org/licenses/>.
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#
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#
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import fcntl
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import logging
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import os
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log = logging.getLogger('cdist-flock')
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class Flock():
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def __init__(self, path):
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self.path = path
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self.lockfd = None
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def flock(self):
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log.debug('Acquiring lock on %s', self.path)
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self.lockfd = open(self.path, 'w+')
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fcntl.flock(self.lockfd, fcntl.LOCK_EX)
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log.debug('Acquired lock on %s', self.path)
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def funlock(self):
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log.debug('Releasing lock on %s', self.path)
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fcntl.flock(self.lockfd, fcntl.LOCK_UN)
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self.lockfd.close()
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self.lockfd = None
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try:
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os.remove(self.path)
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except FileNotFoundError:
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pass
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log.debug('Released lock on %s', self.path)
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def __enter__(self):
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self.flock()
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return self
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def __exit__(self, *args):
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self.funlock()
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return False
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