helpers.py revision 11482
111482Sandreas.sandberg@arm.com#!/usr/bin/env python 211482Sandreas.sandberg@arm.com# 311482Sandreas.sandberg@arm.com# Copyright (c) 2016 ARM Limited 411482Sandreas.sandberg@arm.com# All rights reserved 511482Sandreas.sandberg@arm.com# 611482Sandreas.sandberg@arm.com# The license below extends only to copyright in the software and shall 711482Sandreas.sandberg@arm.com# not be construed as granting a license to any other intellectual 811482Sandreas.sandberg@arm.com# property including but not limited to intellectual property relating 911482Sandreas.sandberg@arm.com# to a hardware implementation of the functionality of the software 1011482Sandreas.sandberg@arm.com# licensed hereunder. You may use the software subject to the license 1111482Sandreas.sandberg@arm.com# terms below provided that you ensure that this notice is replicated 1211482Sandreas.sandberg@arm.com# unmodified and in its entirety in all distributions of the software, 1311482Sandreas.sandberg@arm.com# modified or unmodified, in source code or in binary form. 1411482Sandreas.sandberg@arm.com# 1511482Sandreas.sandberg@arm.com# Redistribution and use in source and binary forms, with or without 1611482Sandreas.sandberg@arm.com# modification, are permitted provided that the following conditions are 1711482Sandreas.sandberg@arm.com# met: redistributions of source code must retain the above copyright 1811482Sandreas.sandberg@arm.com# notice, this list of conditions and the following disclaimer; 1911482Sandreas.sandberg@arm.com# redistributions in binary form must reproduce the above copyright 2011482Sandreas.sandberg@arm.com# notice, this list of conditions and the following disclaimer in the 2111482Sandreas.sandberg@arm.com# documentation and/or other materials provided with the distribution; 2211482Sandreas.sandberg@arm.com# neither the name of the copyright holders nor the names of its 2311482Sandreas.sandberg@arm.com# contributors may be used to endorse or promote products derived from 2411482Sandreas.sandberg@arm.com# this software without specific prior written permission. 2511482Sandreas.sandberg@arm.com# 2611482Sandreas.sandberg@arm.com# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 2711482Sandreas.sandberg@arm.com# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 2811482Sandreas.sandberg@arm.com# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 2911482Sandreas.sandberg@arm.com# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 3011482Sandreas.sandberg@arm.com# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 3111482Sandreas.sandberg@arm.com# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 3211482Sandreas.sandberg@arm.com# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3311482Sandreas.sandberg@arm.com# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3411482Sandreas.sandberg@arm.com# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3511482Sandreas.sandberg@arm.com# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 3611482Sandreas.sandberg@arm.com# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3711482Sandreas.sandberg@arm.com# 3811482Sandreas.sandberg@arm.com# Authors: Andreas Sandberg 3911482Sandreas.sandberg@arm.com 4011482Sandreas.sandberg@arm.comimport subprocess 4111482Sandreas.sandberg@arm.comfrom threading import Timer 4211482Sandreas.sandberg@arm.comimport time 4311482Sandreas.sandberg@arm.com 4411482Sandreas.sandberg@arm.comclass CallTimeoutException(Exception): 4511482Sandreas.sandberg@arm.com """Exception that indicates that a process call timed out""" 4611482Sandreas.sandberg@arm.com 4711482Sandreas.sandberg@arm.com def __init__(self, status, stdout, stderr): 4811482Sandreas.sandberg@arm.com self.status = status 4911482Sandreas.sandberg@arm.com self.stdout = stdout 5011482Sandreas.sandberg@arm.com self.stderr = stderr 5111482Sandreas.sandberg@arm.com 5211482Sandreas.sandberg@arm.comclass ProcessHelper(subprocess.Popen): 5311482Sandreas.sandberg@arm.com """Helper class to run child processes. 5411482Sandreas.sandberg@arm.com 5511482Sandreas.sandberg@arm.com This class wraps a subprocess.Popen class and adds support for 5611482Sandreas.sandberg@arm.com using it in a with block. When the process goes out of scope, it's 5711482Sandreas.sandberg@arm.com automatically terminated. 5811482Sandreas.sandberg@arm.com 5911482Sandreas.sandberg@arm.com with ProcessHelper(["/bin/ls"], stdout=subprocess.PIPE) as p: 6011482Sandreas.sandberg@arm.com return p.call() 6111482Sandreas.sandberg@arm.com """ 6211482Sandreas.sandberg@arm.com def __init__(self, *args, **kwargs): 6311482Sandreas.sandberg@arm.com super(ProcessHelper, self).__init__(*args, **kwargs) 6411482Sandreas.sandberg@arm.com 6511482Sandreas.sandberg@arm.com def _terminate_nicely(self, timeout=5): 6611482Sandreas.sandberg@arm.com def on_timeout(): 6711482Sandreas.sandberg@arm.com self.kill() 6811482Sandreas.sandberg@arm.com 6911482Sandreas.sandberg@arm.com if self.returncode is not None: 7011482Sandreas.sandberg@arm.com return self.returncode 7111482Sandreas.sandberg@arm.com 7211482Sandreas.sandberg@arm.com timer = Timer(timeout, on_timeout) 7311482Sandreas.sandberg@arm.com self.terminate() 7411482Sandreas.sandberg@arm.com status = self.wait() 7511482Sandreas.sandberg@arm.com timer.cancel() 7611482Sandreas.sandberg@arm.com 7711482Sandreas.sandberg@arm.com return status 7811482Sandreas.sandberg@arm.com 7911482Sandreas.sandberg@arm.com def __enter__(self): 8011482Sandreas.sandberg@arm.com return self 8111482Sandreas.sandberg@arm.com 8211482Sandreas.sandberg@arm.com def __exit__(self, exc_type, exc_value, traceback): 8311482Sandreas.sandberg@arm.com if self.returncode is None: 8411482Sandreas.sandberg@arm.com self._terminate_nicely() 8511482Sandreas.sandberg@arm.com 8611482Sandreas.sandberg@arm.com def call(self, timeout=0): 8711482Sandreas.sandberg@arm.com self._timeout = False 8811482Sandreas.sandberg@arm.com def on_timeout(): 8911482Sandreas.sandberg@arm.com self._timeout = True 9011482Sandreas.sandberg@arm.com self._terminate_nicely() 9111482Sandreas.sandberg@arm.com 9211482Sandreas.sandberg@arm.com status, stdout, stderr = None, None, None 9311482Sandreas.sandberg@arm.com timer = Timer(timeout, on_timeout) 9411482Sandreas.sandberg@arm.com if timeout: 9511482Sandreas.sandberg@arm.com timer.start() 9611482Sandreas.sandberg@arm.com 9711482Sandreas.sandberg@arm.com stdout, stderr = self.communicate() 9811482Sandreas.sandberg@arm.com status = self.wait() 9911482Sandreas.sandberg@arm.com 10011482Sandreas.sandberg@arm.com timer.cancel() 10111482Sandreas.sandberg@arm.com 10211482Sandreas.sandberg@arm.com if self._timeout: 10311482Sandreas.sandberg@arm.com self._terminate_nicely() 10411482Sandreas.sandberg@arm.com raise CallTimeoutException(self.returncode, stdout, stderr) 10511482Sandreas.sandberg@arm.com else: 10611482Sandreas.sandberg@arm.com return status, stdout, stderr 10711482Sandreas.sandberg@arm.com 10811482Sandreas.sandberg@arm.comif __name__ == "__main__": 10911482Sandreas.sandberg@arm.com # Run internal self tests to ensure that the helpers are working 11011482Sandreas.sandberg@arm.com # properly. The expected output when running this script is 11111482Sandreas.sandberg@arm.com # "SUCCESS!". 11211482Sandreas.sandberg@arm.com 11311482Sandreas.sandberg@arm.com cmd_foo = [ "/bin/echo", "-n", "foo" ] 11411482Sandreas.sandberg@arm.com cmd_sleep = [ "/bin/sleep", "10" ] 11511482Sandreas.sandberg@arm.com 11611482Sandreas.sandberg@arm.com # Test that things don't break if the process hasn't been started 11711482Sandreas.sandberg@arm.com with ProcessHelper(cmd_foo) as p: 11811482Sandreas.sandberg@arm.com pass 11911482Sandreas.sandberg@arm.com 12011482Sandreas.sandberg@arm.com with ProcessHelper(cmd_foo, stdout=subprocess.PIPE) as p: 12111482Sandreas.sandberg@arm.com status, stdout, stderr = p.call() 12211482Sandreas.sandberg@arm.com assert stdout == "foo" 12311482Sandreas.sandberg@arm.com assert status == 0 12411482Sandreas.sandberg@arm.com 12511482Sandreas.sandberg@arm.com try: 12611482Sandreas.sandberg@arm.com with ProcessHelper(cmd_sleep) as p: 12711482Sandreas.sandberg@arm.com status, stdout, stderr = p.call(timeout=1) 12811482Sandreas.sandberg@arm.com assert False, "Timeout not triggered" 12911482Sandreas.sandberg@arm.com except CallTimeoutException: 13011482Sandreas.sandberg@arm.com pass 13111482Sandreas.sandberg@arm.com 13211482Sandreas.sandberg@arm.com print "SUCCESS!" 133