mirror of
https://github.com/SickGear/SickGear.git
synced 2024-12-21 10:13:39 +00:00
56 lines
1.5 KiB
Python
56 lines
1.5 KiB
Python
from __future__ import annotations
|
|
|
|
import os
|
|
import sys
|
|
from typing import cast
|
|
|
|
from ._api import BaseFileLock
|
|
|
|
#: a flag to indicate if the fcntl API is available
|
|
has_fcntl = False
|
|
if sys.platform == "win32": # pragma: win32 cover
|
|
|
|
class UnixFileLock(BaseFileLock):
|
|
"""Uses the :func:`fcntl.flock` to hard lock the lock file on unix systems."""
|
|
|
|
def _acquire(self) -> None:
|
|
raise NotImplementedError
|
|
|
|
def _release(self) -> None:
|
|
raise NotImplementedError
|
|
|
|
else: # pragma: win32 no cover
|
|
try:
|
|
import fcntl
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
has_fcntl = True
|
|
|
|
class UnixFileLock(BaseFileLock):
|
|
"""Uses the :func:`fcntl.flock` to hard lock the lock file on unix systems."""
|
|
|
|
def _acquire(self) -> None:
|
|
open_mode = os.O_RDWR | os.O_CREAT | os.O_TRUNC
|
|
fd = os.open(self._lock_file, open_mode)
|
|
try:
|
|
fcntl.flock(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
|
|
except OSError:
|
|
os.close(fd)
|
|
else:
|
|
self._lock_file_fd = fd
|
|
|
|
def _release(self) -> None:
|
|
# Do not remove the lockfile:
|
|
# https://github.com/tox-dev/py-filelock/issues/31
|
|
# https://stackoverflow.com/questions/17708885/flock-removing-locked-file-without-race-condition
|
|
fd = cast(int, self._lock_file_fd)
|
|
self._lock_file_fd = None
|
|
fcntl.flock(fd, fcntl.LOCK_UN)
|
|
os.close(fd)
|
|
|
|
|
|
__all__ = [
|
|
"has_fcntl",
|
|
"UnixFileLock",
|
|
]
|