backup_node.py 文件源码

def lock(lockfile):
    def decorator(clbl):
        def wrapper(*args, **kwargs):
            try:
                # Create or fail
                os.open(lockfile, os.O_CREAT | os.O_EXCL)
            except OSError:
                raise BackupError("Another backup process already running."
                                  " If it is not, try to remove `{0}` and "
                                  "try again.".format(lockfile))
            try:
                result = clbl(*args, **kwargs)
            finally:
                os.unlink(lockfile)
            return result

        return wrapper

    return decorator