libpcap/DAG build issues

[Stephen Donnelly]

I have received some reports of issues compiling the current Argus release against recent versions of libpcap built against the current Endace DAG software release.

There seem to be two issues. Firstly static builds of libpcap do not currently work correctly when using the latest DAG software releases. I will submit patches upstream to resolve these issues for static libpcap builds. This will resolve issues building applications that link against static libpcap libraries, provided they use the 'pcap-config' mechanism to pick up additional library dependencies. It will take time any changes to be incorporated into a stable libpcap release version.

Dynamic (shared object) builds of libpcap are currently working correctly with the latest DAG software releases and applications dynamically linking against libpcap are not seeing any issues.

Secondly the Argus aclocal.m4/acsite.m4 defines AC_QOSIENT_LIBPCAP rather than using the upstream AC_LBL_LIBPCAP. This appears to be based on an older version of AC_LBL_LIBPCAP and does not support the 'pcap-config' method. This will not work with the libpcap DAG updates and may not be working for other static libpcap builds with external dependencies.

AC_QOSIENT_LIBPCAP also may not find local installs of libpcap built from git as the egrep regex has not been updated for the git version name scheme (-PRE-GIT).

The simplest solution for these issues may be to pull AC_LBL_LIBPCAP from tcpdump upstream. Argus could call this from inside AC_QOSIENT_LIBPCAP either before or after looking for libpcap variants such as lpcap, wpcap etc? Alternatively at minimum AC_QOSIENT_LIBPCAP needs to be updated to support 'pcap-config'.

Let me know if you want me to submit a patch.

Regards,
Stephen.
-- 
Dr Stephen Donnelly
Core Software Manager 
+64 7 959 2640
stephen.donnelly at endace.com
Level 9, 85 Alexandra St, 
Hamilton 3204, New Zealand. 
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