sensord -p replay data from file, not doing what it should

[bomilkar]

I assume the '-p' option of sensord is there to read data from a file. This data can be used instead of data from sensors.
I would welcome this feature very much because it would help me understand and debug sensord, even if I don't have real sensors connected to the platform I'm debugging on.
One other important benefit of a data replay is to create a repeatable and well defined set of inputs to sensord. This would help analyzing the filters and the functionality in general. Machine generated replay data can be thrown at sensord to see if the expected output is produced.

The issue here: it seems as if the functionality to replay from file got lost. At least it still wants sensors to be connected to do the replay. Is this a reasonable limitation? I think replay should not need sensors at all.

[bomilkar]

I need sensord to replay from a data file (instead of sensors) to test the changes I made to variod Openvario/variod#30

The result is in this commit:
https://github.com/bomilkar/sensord/tree/new_sensord

It replays the sensordata.log which @iglesiasmarianod provided the other day. However, it doesn't get the POV,E, values right. But that's a different issue.

It addresses the NMEA Sentence Structure requirements raised by @moser .

I can make it a PR if @linuxianer99 wants. At least we have a stable basis for further improvements.

[linuxianer99]

We will add software tests and fix the known bugs.
I will merge no new features for the moment.

The NMEA sentence issue can be tested with unit testing functions ...

Lets have prio1 to get stable software, not changing on all ends ...