beremiz

stop PLC before unloading

2016-12-07, Andrey Skvortsov
f5868f866d2b
stop PLC before unloading


This fixes segmentation fault if service was quit without stopping it.
It has happened if Beremiz service was quit using taskbar icon or by
closing Beremiz IDE (in case of autostarted local service).

In second case to trigger the bug following step has to be done:
1. Open Beremiz IDE
2. Open project, compile and connect to LOCAL:// runtime
3. Transfer and start the PLC program
4. Open other project without disconneting the PLC runtime
5. Close Beremiz IDE
<?xml version='1.0' encoding='utf-8'?>
<CFile xmlns:xhtml="http://www.w3.org/1999/xhtml">
<includes>
<xhtml:p><![CDATA[
]]></xhtml:p>
</includes>
<variables>
<variable name="TestInput" type="SINT" initial="0"/>
<variable name="TestOutput" type="SINT"/>
</variables>
<globals>
<xhtml:p><![CDATA[
volatile long Lock=0;
volatile char PtoC=1,CtoP=2;
extern long AtomicCompareExchange(long*,long, long);
extern char *PLC_ID;
int Simple_C_Call(int val){
return val+1;
}
int Python_to_C_Call(char toC, char *fromC){
/* Code called by python should never touch to
variables modified by PLC thread directly
AtomicCompareExchange comes from
beremiz' runtime implementation */
int res = 0;
if(!AtomicCompareExchange((long*)&Lock, 0, 1)){
PtoC=toC;
*fromC=CtoP;
AtomicCompareExchange((long*)&Lock, 1, 0);
res=1;
}
printf("C code called by Python: toC %d fromC %d\n",toC,*fromC);
printf("PLC_ID id %s\n",PLC_ID);
return res;
}
int PLC_C_Call(char fromPLC, char *toPLC){
/* PLC also have to be realy carefull not to
conflict with asynchronous python access */
if(!AtomicCompareExchange((long*)&Lock, 0, 1)){
CtoP = fromPLC;
*toPLC = PtoC;
AtomicCompareExchange((long*)&Lock, 1, 0);
return 1;
}
return 0;
}
]]></xhtml:p>
</globals>
<initFunction>
<xhtml:p><![CDATA[
]]></xhtml:p>
</initFunction>
<cleanUpFunction>
<xhtml:p><![CDATA[
]]></xhtml:p>
</cleanUpFunction>
<retrieveFunction>
<xhtml:p><![CDATA[
]]></xhtml:p>
</retrieveFunction>
<publishFunction>
<xhtml:p><![CDATA[
if(!AtomicCompareExchange((long*)&Lock, 0, 1)){
TestInput = CtoP + PtoC + TestOutput;
AtomicCompareExchange((long*)&Lock, 1, 0);
}
]]></xhtml:p>
</publishFunction>
</CFile>