beremiz

reset loaded messages counts on new PLC program trasnfer

2017-04-05, Andrey Skvortsov
9298ba0cd70a
reset loaded messages counts on new PLC program trasnfer

This fixes the problem that first message from newer PLC program maybe
lost, if it's issued before first PLC log fetching.

Closes #23
<?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>