[mythtv] DVB SI rework - Help needed

[Paul Harrison]

On 20/01/17 21:27, roger wrote:
> Hello list,
>
> I think am getting near to having a beta test version ready. But I have
> one major problem outstanding.
>
> This relates to System Description Tables. The are (should?) only be
> used when channel scanning. However there is a strange piece of code in
> dvbstreamdata.cpp that refernces them:
>
> void DVBStreamData::SetDesiredService(uint netid, uint tsid, int serviceid)
> {
>     bool reset = true;
>
> /*    if (HasAllSDTSections(netid, tsid, TableID::SDT))
>     {
>         // TODO Not sure why this is needed RFJ
>         reset = false;
>         _desired_netid = netid;
>         _desired_tsid = tsid;
>         SetDesiredProgram(serviceid);
>     }*/
>
>     if (reset)
>         Reset(netid, tsid, serviceid);
> }
>
> As you can see I have commented it out in my test version. It is called
> from here:
>
> void DTVSignalMonitor::SetDVBService(uint netid, uint tsid, int serviceid)
>
>
> Which is called from here:
>
> bool TVRec::SetupDTVSignalMonitor(bool EITscan)
>
>
> The only thing I can think of is that it is trying avoid retuning
> everything if it  is already tuned to the correct multiplex. But what
> having a complete SD table has to do with that is not clear.
>
> Does anybody know or care to speculate on what this lump of code is
> trying to achieve?
>
> Roger

Hi Roger,

I just want to say you are not being ignored but it's more likely the 
few remaining active developers don't know the answer to your question :(


I know less about this part of Myth than you do so not going to be much 
help. I did do a little digging in the commits log and came across what 
I think is the original commit message from the old svn days in trac 
that may be of help to you.

https://code.mythtv.org/trac/ticket/1035#comment:42

It looks like Daniel K did most of the work on the EIT rewrite over 10 
years ago now. Even though Daniel is no longer a MythTV dev I always 
found him to be very helpful and he may be able to remember some details 
about that code if you drop him an email.

Paul H.