FileLock/file_lock.py at main · TobiasLibera/FileLock · GitHub

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import fcntl
import os


class FileLock():

    def __init__(self, path, *args, **kwargs):
        self.path = path
        self.file = None
        self.is_locked = False


    def __enter__(self, *args, **kwargs):
        self.acquire()
        return True


    def __exit__(self, exc_type=None, exc_value=None, traceback=None):
        self.release()
        if exc_type != None:
            return False
        return True


    def acquire(self):
        self.file = open(self.path, 'w')
        self._acquire()
        self.is_locked = True


    def release(self):
        self.file.flush()
        os.fsync(self.file.fileno() )
        self._release()
        self.is_locked = False
        self.file.close()
        self.file = None


    def _acquire(self):
        if self.file.writable():
            fcntl.lockf(self.file, fcntl.LOCK_EX)


    def _release(self):
        if self.file.writable():
            fcntl.lockf(self.file, fcntl.LOCK_UN)


    def is_locked(self):
        return self.is_locked


    def acquire(self):
        if self.file.writable():
            fcntl.lockf(self.file, fcntl.LOCK_EX)


    def release(self):
        if self.file.writable():
            fcntl.lockf(self.file, fcntl.LOCK_UN)


    def is_locked(self):
        return self.is_locked