Re: ✘nmea.lasttag

[Gary E. Miller]

Yo Michael!

On Tue, 7 Apr 2020 23:57:17 +0100
"Michael J. Tubby B.Sc. MIET" <address@hidden> wrote:

> If you google for "uint128_t processor support" there's quite a lot
> of noise about either (a) processors or (b) versions of gcc for
> processors that don't support a 128-bit integer type.

Yeah, that is what I feared.  I'm hoping someone has a good idea.

> I'm not exactly sure what you need to achieve but it its bit 
> fields/flags and the like you're probably safer using a list (array)
> of 32-bit or 64-bit integers.

The code in questions is in driver_nmea0183.c, around the nmea.cycle_enders
uint64_t and thistag_mask.

Underlying the code is a simple idea.  For every NMEA sentence, assign
one bit in a uint64_t to see if it is a cycle ender.  But now there are
more tham 64 messages.

I agree with you that an array will be needed.  But the simple bit set and
test will be gone.  It will have to be some small functions.

As gpsd grows, it keeps hitting scaling issues.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
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