# Copyright 2008-2015 Nokia Networks
# Copyright 2016- Robot Framework Foundation
#
# 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
#
# 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.
import ctypes
import time
from threading import current_thread, Lock, Timer
[docs]class Timeout:
def __init__(self, timeout, error):
self._runner_thread_id = current_thread().ident
self._timer = Timer(timeout, self._timed_out)
self._error = error
self._timeout_occurred = False
self._finished = False
self._lock = Lock()
[docs] def execute(self, runnable):
try:
self._start_timer()
try:
result = runnable()
finally:
self._cancel_timer()
self._wait_for_raised_timeout()
return result
finally:
if self._timeout_occurred:
raise self._error
def _start_timer(self):
self._timer.start()
def _cancel_timer(self):
with self._lock:
self._finished = True
self._timer.cancel()
def _wait_for_raised_timeout(self):
if self._timeout_occurred:
while True:
time.sleep(0)
def _timed_out(self):
with self._lock:
if self._finished:
return
self._timeout_occurred = True
self._raise_timeout()
def _raise_timeout(self):
# See, for example, http://tomerfiliba.com/recipes/Thread2/
# for more information about using PyThreadState_SetAsyncExc
tid = ctypes.c_long(self._runner_thread_id)
error = ctypes.py_object(type(self._error))
while ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, error) > 1:
ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, None)
time.sleep(0) # give time for other threads