74 lines
2.2 KiB
Python
74 lines
2.2 KiB
Python
from threading import RLock
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from openflexure_microscope.exceptions import LockError
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class StrictLock(object):
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"""
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Class that behaves like a Python RLock, but with stricter timeout conditions and custom exceptions.
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Args:
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timeout (int): Time, in seconds, lock acquisition will wait before raising an exception
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Attributes:
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_lock (:py:class:`threading.RLock`): Parent RLock object
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timeout (int): Time, in seconds, lock acquisition will wait before raising an exception
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"""
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def __init__(self, timeout=1):
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self._lock = RLock()
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self.timeout = timeout
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def locked(self):
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return self._lock.locked()
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def acquire(self, blocking=True):
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return self._lock.acquire(blocking, timeout=self.timeout)
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def __enter__(self):
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result = self._lock.acquire(blocking=True, timeout=self.timeout)
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if result:
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return result
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else:
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raise LockError('ACQUIRE_ERROR', self)
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def __exit__(self, *args):
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self._lock.release()
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def release(self):
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self._lock.release()
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class CompositeLock(object):
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"""
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Class that behaves like a :py:class:`openflexure_microscope.lock.StrictLock`,
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but allows multiple locks to be acquired and released.
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Args:
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locks (list): List of parent RLock objects
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timeout (int): Time, in seconds, lock acquisition will wait before raising an exception
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Attributes:
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locks (list): List of parent RLock objects
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timeout (int): Time, in seconds, lock acquisition will wait before raising an exception
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"""
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def __init__(self, locks, timeout=1):
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self.locks = locks
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self.timeout = timeout
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def acquire(self, blocking=True):
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return (lock.acquire(blocking=blocking) for lock in self.locks)
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def __enter__(self):
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result = (lock.acquire(blocking=True) for lock in self.locks)
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if all(result):
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return result
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else:
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raise LockError('ACQUIRE_ERROR', self)
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def __exit__(self, *args):
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for lock in self.locks:
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lock.release()
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def release(self):
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for lock in self.locks:
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lock.release()
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