HGKeeper

fix issue with sometimes wrong return code of ProcessLogger

2016-04-28, Andrey Skvortsov

d7f474d10210

Executable

fix issue with sometimes wrong return code of ProcessLogger

As a result of wrong return code Beremiz gives folowing traceback:
Traceback (most recent call last):
File "./Beremiz.py", line 850, in OnMenu
getattr(self.CTR, method)()
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 925, in _Build
IECGenRes = self._Generate_SoftPLC()
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 568, in _Generate_SoftPLC
return self._Compile_ST_to_SoftPLC()
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 661, in _Compile_ST_to_SoftPLC
C_files.remove("POUS.c")
ValueError: list.remove(x): x not in list

The problem is that both threads (for reading stdout and stderr) call self.Proc.poll(),
that updates internal returncode field. This call is done without any locking and the first thread gets correct result,
but other gets 0 as retval. If 0 gets thread, that afterwards calls callback finish, then wrong return code is returned
to the parent. Now only the thread with a callback polls for the return code, other thread just checked local value.

Additionally function spin() waits now until all threads finish reading their pipes, so the results are always correct.

#!/usr/bin/env python

# -*- coding: utf-8 -*-

# See COPYING file for copyrights details.

# This library is free software; you can redistribute it and/or

# modify it under the terms of the GNU General Public

# License as published by the Free Software Foundation; either

# version 2.1 of the License, or (at your option) any later version.

# This library is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

# General Public License for more details.

# You should have received a copy of the GNU General Public

# License along with this library; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

# Package initialisation

from os import listdir, path

_base_path = path.split(__file__)[0]

def _GetLocalConnectorClassFactory(name):

return lambda: getattr(__import__(name, globals(), locals()), name + "_connector_factory")

connectors = {name:_GetLocalConnectorClassFactory(name)

for name in listdir(_base_path)

if path.isdir(path.join(_base_path, name))

and not name.startswith("__")}

def ConnectorFactory(uri, confnodesroot):

"""

Return a connector corresponding to the URI

or None if cannot connect to URI

"""

servicetype = uri.split("://")[0].upper()

if servicetype == "LOCAL":

# Local is special case

# pyro connection to local runtime

# started on demand, listening on random port

servicetype = "PYRO"

runtime_port = confnodesroot.AppFrame.StartLocalRuntime(

taskbaricon=True)

uri = "PYROLOC://127.0.0.1:" + str(runtime_port)

elif servicetype in connectors:

pass

elif servicetype[-1] == 'S' and servicetype[:-1] in connectors:

servicetype = servicetype[:-1]

else:

return None

# import module according to uri type

connectorclass = connectors[servicetype]()

return connectorclass(uri, confnodesroot)