Re: [RFC] get gpsd to work with gnss-share

[Gary E. Miller]

Yo Pavel!

On Mon, 9 Jan 2023 20:33:57 +0100
Pavel Machek <pavel@ucw.cz> wrote:

> > > AFAICT AF_UNIX is already used for the control socket.  
> > 
> > Yes.  Your point?  
> 
> That I did my grep, AF_UNIX is not total weirdness, and that Android
> does not use it.

That is news to no one.  I still miss your point.  Who mentioned wierdness?

> > > > > -    if (0 == getuid()) {
> > > > > +    if (0 && 0 == getuid()) {    
> 
> > Why do you think you need to keep root?  
> 
> I don't. Debugging hack, will remove for submission.

Why do you need it for debugging?  No one else has ever needed that for
debugging.  And you already submitted it.

> > > > Why did the current gpsd/android not need to do this?    
> > > 
> > > I'm not familiar with Android, but I'm pretty sure they are not
> > > using gnss-share.  
> > 
> > So you are not on Android?  I guess I am lost...  
> 
> I'm on PureOs, which is Debian variant for Librem 5 smartphone. But it
> needs gnss-share for geoclue, and I need gpsd for foxtrotgps. Hence
> my patch.

That sorta makes sense now.  Is this where your gnss-share is from:

    https://gitlab.com/postmarketOS/gnss-share

Am I correct that gnss-share only gives you lat/lon, and no more?  I
still need some doc to understand what is happening here.

> > > It carries usual NMEA data. It is very similar to TCP socket, but
> > > it uses filename, not IP+port number. That way, filesystem
> > > permissions can be used to limit who can see the NMEA data.  
> > 
> > If it is NMEA, can you just open it like a file?  Can gpsd also
> > write to it?  
> 
> I don't think gpsd can take output from a file or pipe, it only worked
> with ptyXX or ttyXX in my testing. AF_UNIX can not be simply opened.

You think wrong, but if you need a socket, I expect that can work.

> Should I proceed with cleaning up the code and adding documentation
> for new option?

You are doing the work, so your choice to continue or stop.

> Is it okay to submit patch through the list or do I need to somehow
> create pull request

Merge request is easiest for reviewers.  Next best is create an issue.
But using the list is also fine.

> on https://savannah.nongnu.org/projects/gpsd/ or
> ...?

gpsd has not used that forge for a long time.  Merge Requests and issues
are here now:

https://gitlab.com/gpsd/gpsd

I'm still waiting on doc about this socket protocol.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        gem@rellim.com  Tel:+1 541 382 8588

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