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.
# See COPYING file for copyrights details.
from __future__ import absolute_import
from plcopen.XSLTModelQuery import XSLTModelQuery
from plcopen.types_enums import *
class InstanceTagName(object):
"""Helpers object for generating instance tagname"""
def __init__(self):
self.TagName = None
def GetTagName(self):
return self.TagName
def ConfigTagName(self, context, *args):
self.TagName = ComputeConfigurationName(args[0][0])
def ResourceTagName(self, context, *args):
self.TagName = ComputeConfigurationResourceName(args[0][0], args[1][0])
def PouTagName(self, context, *args):
self.TagName = ComputePouName(args[0][0])
def ActionTagName(self, context, *args):
self.TagName = ComputePouActionName(args[0][0], args[0][1])
def TransitionTagName(self, context, *args):
self.TagName = ComputePouTransitionName(args[0][0], args[0][1])
class InstanceTagnameCollector(XSLTModelQuery):
""" object for collecting instances path list"""
def __init__(self, controller):
XSLTModelQuery.__init__(self,
controller,
"instance_tagname.xslt",
[(name, self.FactoryCaller(name))
for name in ["ConfigTagName",
"ResourceTagName",
"PouTagName",
"ActionTagName",
"TransitionTagName"]])
def FactoryCaller(self, funcname):
def CallFactory(*args):
return getattr(self.factory, funcname)(*args)
return CallFactory
def Collect(self, root, debug, instance_path):
self.factory = InstanceTagName()
self._process_xslt(root, debug, instance_path=instance_path)
res = self.factory.GetTagName()
self.factory = None
return res