Create common GSOF library

[Ryanf55]

Purpose

Factor out the parser into its own library so we can use it in EARHS for the PX1. Do it with as little change to the code as possible.

Testing Done

SITL test flights in a few different modes on copter and plane. I've also tested on the bench hardware connected to SITL. and a flight test.

What changed

95% of the code is the same as before, the only difference is that the number of expected packets (the valid count), is now exposed up to higher levels. The parser used to hard-code 5 different packet types, which breaks down in EARHS.
Otherwise, the parser no longer depends directly on types in AP_GPS, so there are now a function in AP_GPS_GSOF called pack_state_data to go from the packed GSOF data into the AP_GPS struct.

Longer term, I'd like to switch to a bitfield on which packets were received per DCOL frame.

Next up

Add the EARHS. To see the WIP branch, see here: https://github.com/Ryanf55/ardupilot/tree/27033-gsof-add-eahrs-driver

Issue

• Relates to AP_GPS_GSOF: Initial EAHRS support #27033

[Ryanf55]

Flight tests complete.

[tridge]

can just return be32toh_ptr()

[tridge]

should use be16toh_ptr()

[tridge]

please use be32tofloat_ptr()

[tridge]

be64todouble_ptr()

[rmackay9]

I know it's existing code but we normally done use CamelCase... or maybe it's Pascal case.

[tridge]

or remove the function

[Ryanf55]

Valgrind results:

$ valgrind --soname-synonyms=somalloc=nouserintercepts ./build/linux/tests/test_gsof 
==46624== Memcheck, a memory error detector
==46624== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==46624== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==46624== Command: ./build/linux/tests/test_gsof
==46624== 
[==========] Running 2 tests from 1 test suite.
[----------] Global test environment set-up.
[----------] 2 tests from AP_GSOF
[ RUN      ] AP_GSOF.incomplete_packet
[       OK ] AP_GSOF.incomplete_packet (5 ms)
[ RUN      ] AP_GSOF.packet1
[       OK ] AP_GSOF.packet1 (9 ms)
[----------] 2 tests from AP_GSOF (17 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test suite ran. (39 ms total)
[  PASSED  ] 2 tests.
==46624== 
==46624== HEAP SUMMARY:
==46624==     in use at exit: 0 bytes in 0 blocks
==46624==   total heap usage: 222 allocs, 222 frees, 118,093 bytes allocated
==46624== 
==46624== All heap blocks were freed -- no leaks are possible
==46624== 
==46624== For lists of detected and suppressed errors, rerun with: -s
==46624== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

[Ryanf55]

Valgrind doesn't work on the autotest right now:

 ./Tools/autotest/autotest.py build.Copter  test.CopterTests2b.GPSTypes --valgrind
 ...
 arducopter: valgrind: Startup or configuration error:
arducopter: valgrind:    Can't create client cmdline file in /home/ryan/Dev/ardu_ws/src/ardupilot/tmp/valgrind_proc_70431_cmdline_471259db
arducopter: valgrind: Unable to start up properly.  Giving up.
>>>> FAILED STEP: test.CopterTests2b.GPSTypes at Mon May 27 18:29:49 2024 (End Of File (EOF). Exception style platform.
<pexpect.pty_spawn.spawn object at 0x7f23d9dcdd20>
command: /usr/bin/valgrind
args: [b'/usr/bin/valgrind', b'--soname-synonyms=somalloc=nouserintercepts', b'--vgdb-prefix=/tmp/vgdb-pipe', b'-q', b'--log-file=arducopter-+-valgrind.log', b'/home/ryan/Dev/ardu_ws/src/ardupilot/build/sitl/bin/arducopter', b'-w', b'-S', b'--home', b'-35.362938,149.165085,584,270', b'--model', b'+', b'--serial1=tcp:2', b'--defaults', b'/tmp/tmpjmreei1d,/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/default_params/copter.parm']
buffer (last 100 chars): ''
before (last 100 chars): 'pilot/tmp/valgrind_proc_70431_cmdline_471259db\r\nvalgrind: Unable to start up properly.  Giving up.\r\n'
after: <class 'pexpect.exceptions.EOF'>
match: None
match_index: None
exitstatus: None
flag_eof: True
pid: 70431
child_fd: 6
closed: False
timeout: 5
delimiter: <class 'pexpect.exceptions.EOF'>
logfile: <pysim.util.PSpawnStdPrettyPrinter object at 0x7f23d9dce080>
logfile_read: None
logfile_send: None
maxread: 2000
ignorecase: False
searchwindowsize: None
delaybeforesend: 0.05
delayafterclose: 0.1
delayafterterminate: 0.1
searcher: searcher_re:
    0: re.compile('Waiting for '))
Traceback (most recent call last):
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/./Tools/autotest/autotest.py", line 719, in run_tests
    success = run_step(step)
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/./Tools/autotest/autotest.py", line 526, in run_step
    return run_specific_test(specific_test_to_run, binary, **fly_opts)
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/./Tools/autotest/autotest.py", line 387, in run_specific_test
    return tester.autotest(tests=[a], allow_skips=False, step_name=step), tester
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/vehicle_test_suite.py", line 14091, in autotest
    results = self.run_tests(tests)
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/vehicle_test_suite.py", line 11780, in run_tests
    self.init()
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/vehicle_test_suite.py", line 8738, in init
    self.start_SITL()
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/vehicle_test_suite.py", line 8652, in start_SITL
    self.sitl = util.start_SITL(binary, **start_sitl_args)
  File "/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/pysim/util.py", line 608, in start_SITL
    child.expect('Waiting for ', timeout=300)
  File "/home/ryan/.local/lib/python3.10/site-packages/pexpect/spawnbase.py", line 354, in expect
    return self.expect_list(compiled_pattern_list,
  File "/home/ryan/.local/lib/python3.10/site-packages/pexpect/spawnbase.py", line 383, in expect_list
    return exp.expect_loop(timeout)
  File "/home/ryan/.local/lib/python3.10/site-packages/pexpect/expect.py", line 179, in expect_loop
    return self.eof(e)
  File "/home/ryan/.local/lib/python3.10/site-packages/pexpect/expect.py", line 122, in eof
    raise exc
pexpect.exceptions.EOF: End Of File (EOF). Exception style platform.
<pexpect.pty_spawn.spawn object at 0x7f23d9dcdd20>
command: /usr/bin/valgrind
args: [b'/usr/bin/valgrind', b'--soname-synonyms=somalloc=nouserintercepts', b'--vgdb-prefix=/tmp/vgdb-pipe', b'-q', b'--log-file=arducopter-+-valgrind.log', b'/home/ryan/Dev/ardu_ws/src/ardupilot/build/sitl/bin/arducopter', b'-w', b'-S', b'--home', b'-35.362938,149.165085,584,270', b'--model', b'+', b'--serial1=tcp:2', b'--defaults', b'/tmp/tmpjmreei1d,/home/ryan/Dev/ardu_ws/src/ardupilot/Tools/autotest/default_params/copter.parm']
buffer (last 100 chars): ''
before (last 100 chars): 'pilot/tmp/valgrind_proc_70431_cmdline_471259db\r\nvalgrind: Unable to start up properly.  Giving up.\r\n'
after: <class 'pexpect.exceptions.EOF'>
match: None
match_index: None
exitstatus: None
flag_eof: True
pid: 70431
child_fd: 6
closed: False
timeout: 5
delimiter: <class 'pexpect.exceptions.EOF'>
logfile: <pysim.util.PSpawnStdPrettyPrinter object at 0x7f23d9dce080>
logfile_read: None
logfile_send: None
maxread: 2000
ignorecase: False
searchwindowsize: None
delaybeforesend: 0.05
delayafterclose: 0.1
delayafterterminate: 0.1
searcher: searcher_re:
    0: re.compile('Waiting for ')
FAILED 1 tests: ['test.CopterTests2b.GPSTypes']