42 lines
1.2 KiB
Python
42 lines
1.2 KiB
Python
# Copyright 2017 Robert Csordas. All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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#
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# ==============================================================================
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import os
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import fcntl
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class LockFile:
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def __init__(self, fname):
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self._fname = fname
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self._fd = None
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def acquire(self):
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self._fd=open(self._fname, "w")
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os.chmod(self._fname, 0o777)
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fcntl.lockf(self._fd, fcntl.LOCK_EX)
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def release(self):
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fcntl.lockf(self._fd, fcntl.LOCK_UN)
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self._fd.close()
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self._fd = None
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def __enter__(self):
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self.acquire()
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def __exit__(self, exc_type, exc_val, exc_tb):
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self.release()
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