fixes parser / regex errors while parsing IEC61162-450 / LWE sentences

[florian-z]

This fixes sporadic parser / regex errors while parsing IEC61162-450 / LWE sentences, by using the lua string.find(..) with plaintext only attribute instead of a custom escape function: pgsub(str)

[m-rechenberg]

This fixes sporadic parser / regex errors while parsing IEC61162-450 / LWE sentences, by using the lua string.find(..) with plaintext only attribute instead of a custom escape function: pgsub(str)

@florian-z can you provide an example (preferably a pcap) for packets that result in the regex errors you mention?

[m-rechenberg]

@florian-z regarding 9fed42d, why is it necessary to allow additional bytes before the token at the beginning of the nmea string? As far as I know that is not a standard format. Where and why is this used? Can you provide example packets for this as well?

[florian-z]

Thanks for your interest.

sporadic parser / regex errors while parsing IEC61162-450 / LWE sentences
I will look and see if I can find a recording where this "sporadic" error is showing. I should be okay to publish that, as it is a commercial of the shelf product.

additional bytes before the token
Sometimes I work with old naval equipment. One specifically has some weird additions around the actual NMEA sentence.
In general the problem I am trying to fix with this is caused by having characters outside of the allowed NMEA character-set in the udp payload. In my case there is a proprietary header in the udp payload before the actual NMEA-sentence. This header utilizes all byte values [0x00-0xff]. That totally confused this plugin.
I would need to create the data for that on my own, as I think I am not allowed to publish my recordings of this one.