mirror of
https://github.com/ansible-collections/community.general.git
synced 2026-02-04 07:51:50 +00:00
3478863ef0
* Resolve E713 and E714 (not in/is tests). * Address UP018 (unnecessary str call). * UP045 requires Python 3.10+. * Address UP007 (X | Y for type annotations). * Address UP035 (import Callable from collections.abc). * Address UP006 (t.Dict -> dict). * Address UP009 (UTF-8 encoding comment). * Address UP034 (extraneous parantheses). * Address SIM910 (dict.get() with None default). * Address F401 (unused import). * Address UP020 (use builtin open). * Address B009 and B010 (getattr/setattr with constant name). * Address SIM300 (Yoda conditions). * UP029 isn't in use anyway. * Address FLY002 (static join). * Address B034 (re.sub positional args). * Address B020 (loop variable overrides input). * Address B017 (assert raise Exception). * Address SIM211 (if expression with false/true). * Address SIM113 (enumerate for loop). * Address UP036 (sys.version_info checks). * Remove unnecessary UP039. * Address SIM201 (not ==). * Address SIM212 (if expr with twisted arms). * Add changelog fragment. * Reformat.
105 lines
3.2 KiB
Python
105 lines
3.2 KiB
Python
# Copyright (c) 2018, Ansible Project
|
|
# Simplified BSD License (see licenses/simplified_bsd.txt or https://opensource.org/licenses/BSD-2-Clause)
|
|
# SPDX-License-Identifier: BSD-2-Clause
|
|
|
|
# NOTE:
|
|
# This has been vendored from ansible.module_utils.common.file. This code has been removed from there for ansible-core 2.16.
|
|
|
|
from __future__ import annotations
|
|
|
|
import os
|
|
import stat
|
|
import time
|
|
import fcntl
|
|
|
|
from contextlib import contextmanager
|
|
|
|
|
|
class LockTimeout(Exception):
|
|
pass
|
|
|
|
|
|
class FileLock:
|
|
"""
|
|
Currently FileLock is implemented via fcntl.flock on a lock file, however this
|
|
behaviour may change in the future. Avoid mixing lock types fcntl.flock,
|
|
fcntl.lockf and module_utils.common.file.FileLock as it will certainly cause
|
|
unwanted and/or unexpected behaviour
|
|
"""
|
|
|
|
def __init__(self):
|
|
self.lockfd = None
|
|
|
|
@contextmanager
|
|
def lock_file(self, path, tmpdir, lock_timeout=None):
|
|
"""
|
|
Context for lock acquisition
|
|
"""
|
|
try:
|
|
self.set_lock(path, tmpdir, lock_timeout)
|
|
yield
|
|
finally:
|
|
self.unlock()
|
|
|
|
def set_lock(self, path, tmpdir, lock_timeout=None):
|
|
"""
|
|
Create a lock file based on path with flock to prevent other processes
|
|
using given path.
|
|
Please note that currently file locking only works when it is executed by
|
|
the same user, for example single user scenarios
|
|
|
|
:kw path: Path (file) to lock
|
|
:kw tmpdir: Path where to place the temporary .lock file
|
|
:kw lock_timeout:
|
|
Wait n seconds for lock acquisition, fail if timeout is reached.
|
|
0 = Do not wait, fail if lock cannot be acquired immediately,
|
|
Default is None, wait indefinitely until lock is released.
|
|
:returns: True
|
|
"""
|
|
lock_path = os.path.join(tmpdir, f"ansible-{os.path.basename(path)}.lock")
|
|
l_wait = 0.1
|
|
|
|
self.lockfd = open(lock_path, "w")
|
|
|
|
if lock_timeout <= 0:
|
|
fcntl.flock(self.lockfd, fcntl.LOCK_EX | fcntl.LOCK_NB)
|
|
os.chmod(lock_path, stat.S_IWRITE | stat.S_IREAD)
|
|
return True
|
|
|
|
if lock_timeout:
|
|
e_secs = 0
|
|
while e_secs < lock_timeout:
|
|
try:
|
|
fcntl.flock(self.lockfd, fcntl.LOCK_EX | fcntl.LOCK_NB)
|
|
os.chmod(lock_path, stat.S_IWRITE | stat.S_IREAD)
|
|
return True
|
|
except BlockingIOError:
|
|
time.sleep(l_wait)
|
|
e_secs += l_wait
|
|
continue
|
|
|
|
self.lockfd.close()
|
|
raise LockTimeout(f"{lock_timeout} sec")
|
|
|
|
fcntl.flock(self.lockfd, fcntl.LOCK_EX)
|
|
os.chmod(lock_path, stat.S_IWRITE | stat.S_IREAD)
|
|
|
|
return True
|
|
|
|
def unlock(self):
|
|
"""
|
|
Make sure lock file is available for everyone and Unlock the file descriptor
|
|
locked by set_lock
|
|
|
|
:returns: True
|
|
"""
|
|
if not self.lockfd:
|
|
return True
|
|
|
|
try:
|
|
fcntl.flock(self.lockfd, fcntl.LOCK_UN)
|
|
self.lockfd.close()
|
|
except ValueError: # file wasn't opened, let context manager fail gracefully
|
|
pass
|
|
|
|
return True
|