beremiz

use pregenerated CRC32 lookup tables for retain on Win32 and GNU/Linux

2019-01-06, Andrey Skvortsov
68f4f2d4516b
use pregenerated CRC32 lookup tables for retain on Win32 and GNU/Linux

This code could be possible reused on low-end targets with limited RAM.

code to generate lookup table:
[---------------------------------------------------------------------]

/* CRC lookup table and initial state. */
uint32_t crc32_table[256];

/* Generate CRC32 lookup table. */
void GenerateCRC32Table(void)
{
unsigned int i, j;
/* Use CRC-32-IEEE 802.3 polynomial 0x04C11DB7 (bit reflected). */
uint32_t poly = 0xEDB88320;

for (i = 0; i <= 0xFF; i++)
{
uint32_t c = i;
for (j = 0 ; j < 8 ; j++)
c = (c & 1) ? (c >> 1 ) ^ poly : (c >> 1);
crc32_table[i] = c;
}
}

void main(void)
{
GenerateCRC32Table();
int j=0;
for(int i=0; i<256; i++) {
printf("0x%08X, ", crc32_table[i]);
if (++j >= 8) {
j = 0;
printf("\n");
}
}
}
[---------------------------------------------------------------------]
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# This file is part of Beremiz, a Integrated Development Environment for
# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.
#
# Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
#
# See COPYING file for copyrights details.
#
# This program 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
# of the License, or (at your option) any later version.
#
# This program 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 program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
from __future__ import absolute_import
import subprocess
import wx
import wx.html
HtmlFrameOpened = []
def OpenHtmlFrame(self, title, file, size):
if title not in HtmlFrameOpened:
HtmlFrameOpened.append(title)
window = HtmlFrame(self, HtmlFrameOpened)
window.SetTitle(title)
window.SetHtmlPage(file)
window.SetClientSize(size)
window.Show()
[ID_HTMLFRAME, ID_HTMLFRAMEHTMLCONTENT] = [wx.NewId() for _init_ctrls in range(2)]
EVT_HTML_URL_CLICK = wx.NewId()
class HtmlWindowUrlClick(wx.PyEvent):
def __init__(self, linkinfo):
wx.PyEvent.__init__(self)
self.SetEventType(EVT_HTML_URL_CLICK)
self.linkinfo = (linkinfo.GetHref(), linkinfo.GetTarget())
class UrlClickHtmlWindow(wx.html.HtmlWindow):
""" HTML window that generates and OnLinkClicked event.
Use this to avoid having to override HTMLWindow
"""
def OnLinkClicked(self, linkinfo):
wx.PostEvent(self, HtmlWindowUrlClick(linkinfo))
def Bind(self, event, handler, source=None, id=wx.ID_ANY, id2=wx.ID_ANY):
if event == HtmlWindowUrlClick:
self.Connect(-1, -1, EVT_HTML_URL_CLICK, handler)
else:
wx.html.HtmlWindow.Bind(self, event, handler, source=source, id=id, id2=id2)
class HtmlFrame(wx.Frame):
def _init_ctrls(self, prnt):
self.SetIcon(prnt.icon)
self.Bind(wx.EVT_CLOSE, self.OnCloseFrame)
self.HtmlContent = UrlClickHtmlWindow(id=ID_HTMLFRAMEHTMLCONTENT,
name='HtmlContent', parent=self, pos=wx.Point(0, 0),
size=wx.Size(-1, -1), style=wx.html.HW_SCROLLBAR_AUTO | wx.html.HW_NO_SELECTION)
self.HtmlContent.Bind(HtmlWindowUrlClick, self.OnLinkClick)
def __init__(self, parent, opened):
wx.Frame.__init__(self, id=ID_HTMLFRAME, name='HtmlFrame',
parent=parent, pos=wx.Point(320, 231),
size=wx.Size(853, 616),
style=wx.DEFAULT_FRAME_STYLE, title='')
self._init_ctrls(parent)
self.HtmlFrameOpened = opened
def SetHtmlCode(self, htmlcode):
self.HtmlContent.SetPage(htmlcode)
def SetHtmlPage(self, htmlpage):
self.HtmlContent.LoadPage(htmlpage)
def OnCloseFrame(self, event):
self.HtmlFrameOpened.remove(self.GetTitle())
event.Skip()
def OnLinkClick(self, event):
url = event.linkinfo[0]
try:
if wx.Platform == '__WXMSW__':
import webbrowser
webbrowser.open(url)
elif subprocess.call("firefox %s" % url, shell=True) != 0:
wx.MessageBox("""Firefox browser not found.\nPlease point your browser at :\n%s""" % url)
except ImportError:
wx.MessageBox('Please point your browser at: %s' % url)