29 Jun
2011
29 Jun
'11
4:50 p.m.
Am 2011-06-28 20:56, schrieb Daniel-Constantin Mierla:
...
Jepp, of course you are right. The (overloaded) downstream server takes
the remaining topmost Via header of the response and manipulates the
oc-parameter according its overload state.
...
ok.
Well, and now
my problem: Manipulating the own Via-Header is (in my
understanding) a very tricky part: in msg_translator.c the functions
"build_req_buf_from_sip_req()" and "build_res_bug_from_sip_res()"
are
responsible for adding the own Via-Header and its parameters.
When building the response there is no own via, the first via will be
the previous hop in the request path, do you need to update that one as
well? And here is
the problem: I cannot access the shared memory variables of
the oc-module like oc_duration and oc_droprate when I call the
oc_via_manipulation() and oc_builder()-functions from within
"build_req_buf_from_sip_req()" and "build_res_bug_from_sip_res()".
My
conclusion was, that when calling functions of the oc-module from within
the ser-"core", the shared-memory variables set by rpc_methods, cmds and
params are not accessible.
The shared memory is available in the core, so it should be no problem
to access it. The problem might be how you pass the pointers to the
share memory. Normally, the core should not call the functions
implemented by the
module directly, but via some interface. How do you get the pointers to
your module functions to be executed from the core?
Well, I am defintely no C freak. My first try was to create an oc.h and
include it into the msg_translator.c. Like described, this compiled, but
did not work.
Any hint what to change to get this running as a proof-of-concept
implementation?
Like an idea right now, we could think about a generic
function to add
extra parameters to own via header to be offered by the core and called
from inside modules.
I think, this would be a good approach as there are other discussions
about extending the Via-Headers (like for Spit protection).
BR
Michael
Cheers,
Daniel
Honestly, I have now no idea how to continue and would be happy on every
idea,
br
Michael