1 Dec
2012
1 Dec
'12
5:04 a.m.
On Nov 30, 2012, at 5:23 PM, Robert Boisvert <rdboisvert(a)gmail.com> wrote:
Andrew,
Congratulations on your new position as a Kamailio developer! When I saw your module
(SCA) I began testing immediately since it may be a stepping stone to help me get the
Polycom barge-in feature working with Kamailio. However, I ran into a few difficulties.
Can you assist me?
Thanks for the kind words. I'll do my best to help.
To make your existing code work as a K module I had to
change a few lines of code and recompile under modules_k. Specifically, since the K
definition of the ucontact structure defines ucontact->aor as str* and the S definition
as str**, I changed “&c->aor” to “c->aor” in the following lines of
sca_usrloc_cb.c:
73: if ( !sca_uri_is_shared_appearance( sca, c->aor )) {
74: LM_DBG( "%.*s is not a shared appearance line", STR_FMT( c->aor ));
79: &SCA_EVENT_NAME_CALL_INFO, c->aor ) < 0 ) {
This is no longer necessary, fortunately. The sca module no longer depends on usrloc.
I've merged it into the project's master branch, in the modules directory. You
should still be able to build it against the 3.3 branch.
Since I use PostgreSQL as my SQL engine I created the
SCA entries using this code:
I've also added an sca db schema file, so the db creation scripts get created
automatically. Ovidiu generated the PostgreSQL create script, which you can find on the
master branch in utils/kamctl/postgres.
I applied the recommendations from your documentation
on configuring Kamailio (3.3.1) and inserted the call to “sca_handle_subscribe ()” in
kamailio.cfg.
... snip ...
When I ran a tcpdump of the SIP communication (see attached pcap files) I found several
anomalies:
• Some packets (sca-reboot1 #22, 44, 113, 120 and sca-reboot2 #17, 38) contain spurious
NUL characters in the tags section. In all tests it seems to occur in the Expire tag when
Kamailio accepts the subscription.
Thanks for the captures. I've tracked down the cause for the NUL in the Expires
header, and have committed a fix. (Misplaced parenthesis when writing the Expires value
• When Kamailio sends call-info NOTIFY the
Content-Length tag is missing.
It's there, it's just not the last header in the packet. If you do actually find a
packet without Content-Length header, please let me know. It *must* be there when using
TCP.
• Sometimes the phone does not respond to a call-info
NOTIFY event (sca-reboot1 #23, 45 and sca-reboot2 #18, 39).
This may be related to the NUL in the Expires header problem fixed above. Because the
Expires line in the response gets mangled, the subscriber may be throwing away the
subscription and ignoring the NOTIFY. Please grab the updated source and let me know if it
fixes things for you.
I think some of my problems are related to these
anomalies.
I agree. I've done the bulk of my testing with UDP to this point, too, so there may be
assumptions in the code that are stumbling over TCP. I'll try to remedy that.
Thanks for your very helpful report!
Best,
andrew