Re: [gpsd-dev] Half the port problems are solved; seeking help with RTCM2 driver

[Bernd Zeimetz]

On 04/20/2012 12:34 PM, Eric S. Raymond wrote:
> Hard confirmation will await the scheduled buildd run of GPSD
> regression tests on all porterboxes, but I believe from results on I
> see on an s390x machine that about half of the port problems I listed
> on 17 April are now solved.
> 
> It looks like all the regression failures on the italk-binary,
> trimble, and uBlox tests were due to a point bug in a very obscure
> place; the initializer for our internal geoid separation table was,
> inexplicably, declared char even though it contained signed integer
> values.  I suspect that the architectures on which these tests failed
> were those on which char is unsigned.

Almost all architectures have built the new gpsd upload now. Indeed the
italk/trimble and ublox issues are fixed and the najoks + rtcm2 tests still 
fail.

gpsd_3.5-4_s390.log:--- test/daemon/naujoks-ntrip.log.chk       2012-03-05
00:13:03.000000000 +0000
gpsd_3.5-4_s390.log:--- test/daemon/naujoks-rtcm2.log.chk       2012-03-05
00:13:04.000000000 +0000
gpsd_3.5-4_s390.log:--- test/daemon/rtcm2.log.chk       2012-03-05 
00:13:17.000000000
+0000
gpsd_3.5-4_s390x.log:--- test/daemon/naujoks-ntrip.log.chk      2012-03-05
00:13:03.000000000 +0000
gpsd_3.5-4_s390x.log:--- test/daemon/naujoks-rtcm2.log.chk      2012-03-05
00:13:04.000000000 +0000
gpsd_3.5-4_s390x.log:--- test/daemon/rtcm2.log.chk      2012-03-05 
00:13:17.000000000
+0000
gpsd_3.5-4_sparc.log:--- test/daemon/naujoks-ntrip.log.chk      2012-03-05
00:13:03.000000000 +0000
gpsd_3.5-4_sparc.log:--- test/daemon/naujoks-rtcm2.log.chk      2012-03-05
00:13:04.000000000 +0000
gpsd_3.5-4_sparc.log:--- test/daemon/rtcm2.log.chk      2012-03-05 
00:13:17.000000000
+0000


> 
> It appears that all of the remaining port failures are due to some
> strange type punning in the RTCM2 driver.  That module (with the ISGPS
> code it uses) is the blackest magic in the GPSD codebase; I
> successfully modified it from contributed code, but I don't fully
> understand it.
> 
> I need help from some very experienced C programmer with lots of
> experience in weird bit-bashing and troubleshooting endianness
> problems, to check my assumptions and help me fix this. If you're such
> a person and up for a challenge, read isgps.c and driver_rtcm2.c and
> find me on the #gpsd channel of freenode.


-- 
 Bernd Zeimetz                            Debian GNU/Linux Developer
 http://bzed.de                                http://www.debian.org
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