[Discuss-gnuradio] Porting cgran AIS to the new cmake build system

[Christian Gagneraud]

Hi,

I tried to build https://cgran.org/wiki/AIS against gnuradio-3.6, and i 
fails.
As 3.6 brings in a new build system, I decided to give it a go on the 
AIS module. I based everything on gr-howto-write-a-block

I can build and install everything, here is what get installed:
address@hidden:~/Downloads/gr-ais-ng/build> sudo make install
[ 22%] Built target gnuradio-ais
[ 27%] Built target _ais_swig_swig_tag
[ 31%] Built target _ais_swig_doc_tag
[ 54%] Built target _ais_swig
[ 81%] Built target pygen_swig_a8cc0
[ 90%] Built target pygen_python_a8569
[100%] Built target pygen_apps_4b161
Linking CXX shared module CMakeFiles/CMakeRelink.dir/_ais_swig.so
Install the project... 

-- Install configuration: "Release" 

-- Up-to-date: /usr/local/include/ais/ais_unstuff.h
-- Up-to-date: /usr/local/include/ais/ais_shift.h
-- Up-to-date: /usr/local/include/ais/ais_parse.h
-- Up-to-date: /usr/local/include/ais/ais_invert.h
-- Up-to-date: /usr/local/include/ais/ais_extended_lms_dfe_ff.h
-- Up-to-date: /usr/local/lib/libgnuradio-ais.so
-- Installing: /usr/local/lib/python2.7/site-packages/ais/_ais_swig.so
-- Installing: /usr/local/lib/python2.7/site-packages/ais/ais_swig.py
-- Installing: /usr/local/lib/python2.7/site-packages/ais/ais_swig.pyc
-- Installing: /usr/local/lib/python2.7/site-packages/ais/ais_swig.pyo
-- Installing: /usr/local/include/ais/swig/ais_swig.i
-- Up-to-date: /usr/local/include/ais/swig/ais_swig_doc.i
-- Up-to-date: /usr/local/lib/python2.7/site-packages/ais/__init__.py
-- Up-to-date: /usr/local/lib/python2.7/site-packages/ais/__init__.pyc
-- Up-to-date: /usr/local/lib/python2.7/site-packages/ais/__init__.pyo
-- Up-to-date: /usr/local/bin/ais_decode.py
-- Up-to-date: /usr/local/bin/ais_demod.py

But now, if I want to test one of the "app", this is what i get:
address@hidden:~/Downloads/gnuradio-3.6.0> ais_decode.py
Traceback (most recent call last):
  File "/usr/local/bin/ais_decode.py", line 13, in <module>
    import ais
  File "/usr/local/lib/python2.7/site-packages/ais/__init__.py", line 
46, in <module>
    from ais_swig import *
  File "/usr/local/lib/python2.7/site-packages/ais/ais_swig.py", line 
26, in <module>
    _ais_swig = swig_import_helper()
  File "/usr/local/lib/python2.7/site-packages/ais/ais_swig.py", line 
22, in swig_import_helper
    _mod = imp.load_module('_ais_swig', fp, pathname, description)
ImportError: /usr/local/lib/python2.7/site-packages/ais/_ais_swig.so: 
undefined symbol: _Z14ais_make_shiftv

I have the same result if i try to "import ais" within a python console.

now ldd tells me that:
address@hidden:~/Downloads/gnuradio-3.6.0> ldd 
/usr/local/lib/python2.7/site-packages/ais/_ais_swig.so
        linux-gate.so.1 =>  (0xffffe000)
        libpython2.7.so.1.0 => /usr/lib/libpython2.7.so.1.0 (0xb75c4000)
        libgnuradio-ais.so => /usr/local/lib/libgnuradio-ais.so 
(0xb75bb000)
        libgruel-3.6.0.so.0.0.0 => 
/usr/local/lib/libgruel-3.6.0.so.0.0.0 (0xb7580000)
        libgnuradio-core-3.6.0.so.0.0.0 => 
/usr/local/lib/libgnuradio-core-3.6.0.so.0.0.0 (0xb73c7000)
        libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0xb72d8000)
        libm.so.6 => /lib/libm.so.6 (0xb72ad000)
        libgcc_s.so.1 => /lib/libgcc_s.so.1 (0xb728f000)
        libc.so.6 => /lib/libc.so.6 (0xb7122000)
        libpthread.so.0 => /lib/libpthread.so.0 (0xb7107000)
        libdl.so.2 => /lib/libdl.so.2 (0xb7102000)
        libutil.so.1 => /lib/libutil.so.1 (0xb70fd000)
        libboost_date_time.so.1.46.1 => 
/usr/lib/libboost_date_time.so.1.46.1 (0xb70ec000)
        libboost_program_options.so.1.46.1 => 
/usr/lib/libboost_program_options.so.1.46.1 (0xb708c000)
        libboost_filesystem.so.1.46.1 => 
/usr/lib/libboost_filesystem.so.1.46.1 (0xb706e000)
        libboost_system.so.1.46.1 => /usr/lib/libboost_system.so.1.46.1 
(0xb706a000)
        libboost_thread.so.1.46.1 => /usr/lib/libboost_thread.so.1.46.1 
(0xb7051000)
        libfftw3f.so.3 => /usr/lib/libfftw3f.so.3 (0xb6efe000)
        librt.so.1 => /lib/librt.so.1 (0xb6ef5000)
        libvolk.so.0.0.0 => /usr/local/lib/libvolk.so.0.0.0 (0xb6dfb000)
        /lib/ld-linux.so.2 (0xb7798000)

And a dirty grep for the symbol gives:
address@hidden:~/Downloads/gr-ais-ng/build> grep _Z14ais_make_shiftv 
/usr/local/lib/libgnuradio-ais.so 
/usr/local/lib/python2.7/site-packages/ais/_ais_swig.so
Binary file /usr/local/lib/libgnuradio-ais.so matches
Binary file /usr/local/lib/python2.7/site-packages/ais/_ais_swig.so matches

So, /lib/python2.7/site-packages/ais/_ais_swig.so really depends on 
/usr/local/lib/libgnuradio-ais.so (which is, I guess, where the missing 
symbol is). but python can't load the module due to unresolved symbol...

Note: I have /usr/local/lib in my LD_LIBRARY_PATH and 
/usr/local/lib/python2.7/site-packages/ in my PYTHONPATH

The only change in the source code I had to do was to replace in 
ais_decode.py:
from gnuradio import ais
with:
import ais

Does anyone has an idea on what is goin on here? I certainly did 
something wrong, or fogot something, but I can't see it.

Regards,
Chris


--
Christian Gagneraud,
Embedded systems engineer.
Techworks Marine
1 Harbour road
Dun Laoghaire
Co. Dublin
Ireland
Tel: + 353 (0) 1 236 5990
Web: http://www.techworks.ie/