beremiz

fix issue with sometimes wrong return code of ProcessLogger

2016-04-28, Andrey Skvortsov
d7f474d10210
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 -*-
#This file is part of PLCOpenEditor, a library implementing an IEC 61131-3 editor
#based on the plcopen standard.
#
#Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
#
#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
import wx
from graphics.GraphicCommons import GetScaledEventPosition
#-------------------------------------------------------------------------------
# Viewer RubberBand
#-------------------------------------------------------------------------------
"""
Class that implements a rubberband for graphic Viewers
"""
class RubberBand:
def __init__(self, viewer):
"""
Constructor
@param viewer: Viewer on which rubberband must be drawn
"""
self.Viewer = viewer
# wx.Panel on which rubberband will be drawn
self.DrawingSurface = viewer.Editor
self.Reset()
def Reset(self):
"""
Initialize internal attributes of rubberband
"""
self.StartPoint = None
self.CurrentBBox = None
self.LastBBox = None
def IsShown(self):
"""
Indicate if rubberband is drawn on viewer
@return: True if rubberband is drawn
"""
return self.CurrentBBox != None
def GetCurrentExtent(self):
"""
Return the rubberband bounding box
@return: Rubberband bounding box (wx.Rect object)
"""
# In case of rubberband not shown, return the last rubberband
# bounding box
if self.IsShown():
return self.CurrentBBox
return self.LastBBox
def OnLeftDown(self, event, dc, scaling):
"""
Called when left mouse is pressed on Viewer. Starts to edit a new
rubberband bounding box
@param event: Mouse event
@param dc: Device Context of Viewer
@param scaling: PLCOpen scaling applied on Viewer
"""
# Save the point where mouse was pressed in Viewer unit, position may
# be modified by scroll and zoom applied on viewer
self.StartPoint = GetScaledEventPosition(event, dc, scaling)
# Initialize rubberband bounding box
self.CurrentBBox = wx.Rect(self.StartPoint.x, self.StartPoint.y, 0, 0)
# Change viewer mouse cursor to reflect a rubberband bounding box is
# edited
self.DrawingSurface.SetCursor(wx.StockCursor(wx.CURSOR_CROSS))
self.Redraw()
def OnMotion(self, event, dc, scaling):
"""
Called when mouse is dragging over Viewer. Update the current edited
rubberband bounding box
@param event: Mouse event
@param dc: Device Context of Viewer
@param scaling: PLCOpen scaling applied on Viewer
"""
# Get mouse position in Viewer unit, position may be modified by scroll
# and zoom applied on viewer
pos = GetScaledEventPosition(event, dc, scaling)
# Save the last bounding box drawn for erasing it later
self.LastBBox = wx.Rect(0, 0, 0, 0)
self.LastBBox.Union(self.CurrentBBox)
# Calculate new position and size of the box
self.CurrentBBox.x = min(pos.x, self.StartPoint.x)
self.CurrentBBox.y = min(pos.y, self.StartPoint.y)
self.CurrentBBox.width = abs(pos.x - self.StartPoint.x) + 1
self.CurrentBBox.height = abs(pos.y - self.StartPoint.y) + 1
self.Redraw()
def OnLeftUp(self, event, dc, scaling):
"""
Called when mouse is release from Viewer. Erase the current edited
rubberband bounding box
@param event: Mouse event
@param dc: Device Context of Viewer
@param scaling: PLCOpen scaling applied on Viewer
"""
# Change viewer mouse cursor to default
self.DrawingSurface.SetCursor(wx.NullCursor)
# Save the last edited bounding box
self.LastBBox = self.CurrentBBox
self.CurrentBBox = None
self.Redraw()
def DrawBoundingBoxes(self, bboxes, dc=None):
"""
Draw a list of bounding box on Viewer in the order given using XOR
logical function
@param bboxes: List of bounding boxes to draw on viewer
@param dc: Device Context of Viewer (default None)
"""
# Get viewer Device Context if not given
if dc is None:
dc = self.Viewer.GetLogicalDC()
# Save current viewer scale factors before resetting them in order to
# avoid rubberband pen to be scaled
scalex, scaley = dc.GetUserScale()
dc.SetUserScale(1, 1)
# Set DC drawing style
dc.SetPen(wx.Pen(wx.WHITE, style=wx.DOT))
dc.SetBrush(wx.TRANSPARENT_BRUSH)
dc.SetLogicalFunction(wx.XOR)
# Draw the bounding boxes using viewer scale factor
for bbox in bboxes:
if bbox is not None:
dc.DrawRectangle(
bbox.x * scalex, bbox.y * scaley,
bbox.width * scalex, bbox.height * scaley)
dc.SetLogicalFunction(wx.COPY)
# Restore Viewer scale factor
dc.SetUserScale(scalex, scaley)
def Redraw(self, dc = None):
"""
Redraw rubberband on Viewer
@param dc: Device Context of Viewer (default None)
"""
# Erase last bbox and draw current bbox
self.DrawBoundingBoxes([self.LastBBox, self.CurrentBBox], dc)
def Erase(self, dc = None):
"""
Erase rubberband from Viewer
@param dc: Device Context of Viewer (default None)
"""
# Erase last bbox
self.DrawBoundingBoxes([self.LastBBox], dc)
def Draw(self, dc = None):
"""
Draw rubberband on Viewer
@param dc: Device Context of Viewer (default None)
"""
# Erase last bbox and draw current bbox
self.DrawBoundingBoxes([self.CurrentBBox], dc)