58 lines
1.9 KiB
Python
58 lines
1.9 KiB
Python
# TLock: OpenSSL lock support on thread-enabled systems.
|
|
|
|
# Copyright 2012 Ray Brown
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# The License is also distributed with this work in the file named "LICENSE."
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
"""TLock
|
|
|
|
This module provides the callbacks required by the OpenSSL library in situations
|
|
where it is being entered concurrently by multiple threads. This module is
|
|
enagaged automatically by the PyDTLS package on systems that have Python
|
|
threading support. It does not have client-visible components.
|
|
"""
|
|
|
|
from logging import getLogger
|
|
from openssl import *
|
|
|
|
try:
|
|
import threading
|
|
except ImportError:
|
|
pass
|
|
|
|
_logger = getLogger(__name__)
|
|
DO_DEBUG_LOG = False
|
|
|
|
def tlock_init():
|
|
if not globals().has_key("threading"):
|
|
return # nothing to configure
|
|
# The standard library ssl module's lock implementation is more efficient;
|
|
# do not override it if it has been established
|
|
if CRYPTO_get_id_callback():
|
|
return
|
|
global _locks
|
|
num_locks = CRYPTO_num_locks()
|
|
_locks = tuple(threading.Lock() for _ in range(num_locks))
|
|
CRYPTO_set_locking_callback(_locking_function)
|
|
|
|
def _locking_function(mode, n, file, line):
|
|
if DO_DEBUG_LOG:
|
|
_logger.debug("Thread lock: mode: %d, n: %d, file: %s, line: %d",
|
|
mode, n, file, line)
|
|
if mode & CRYPTO_LOCK:
|
|
_locks[n].acquire()
|
|
else:
|
|
_locks[n].release()
|