10 Jan
2003
10 Jan
'03
11:50 p.m.
Thank you for the explanation! Attached please find first version
of `rport' support for SER (we need it in the core engine), the
module will follow probably tomorrow. Please note that the code
is quite raw (6:20 am here ;) and I did not perform any seriuos
tests yet.
The code does the following:
1. Adds support for `rport' Via field parameter into the message
parser;
2. Extends parser to allow valueless parameters as requred by
the draft RFC. This will probably requre additional code
review, as there may be places in the code where it is
assumed that parameter value could not be a NULL pointer;
3. Fills in blank rport parameter if present before forwarding
a request or replying to it;
4. Changes the code, so that if `rport' is present, then this
port is used for connecting to that UA.
Any comments, corrections or suggestions are highly appreciated!
-Maxim
On Sat, Jan 11, 2003 at 12:04:34AM +0100, Jiri Kuthan wrote:
that's correct.
1. Check that _m->somefield is NULL and call
parse_headers() with the
appropriate HDR_FOO flag.
yes. you can skip the first check, parse_headers will do it;
don't forget to handle errors if parse_headers returns -1
(most likely mem alloc failure)
2. Check that _m->somefield is non-NULL and
return if false.
yes, that means, that the header field is not in message.
note too that some header fields may occur multiple times; in which case
msg->hdr_foo points to the first occurence; if you wish to
process all of them, you need to traverse the list
msg->headers
example from record-routing (XXX are my extra comments):
int find_first_route(struct sip_msg* _m)
{
/* XXX don't look at _m->route ... parse_headers will do it for you */
if (parse_headers(_m, HDR_ROUTE, 0) == -1) {
/* XXX -1 is some bad error, most likely lack of memory -- leave! */
LOG(L_ERR, "find_first_route(): Error while parsing headers\n");
return -1;
} else {
if (_m->route) {
return 0;
} else { /* XXX not found .... the header field is not there */
DBG("find_first_route(): No Route headers found\n");
return 1;
}
}
}
3. Modify _m->somefield according to the type
of that field.
4. Using del_lump() mark original version of the header for deletion and
using insert_new_lump() indicate where modified version should be placed
before sending a message out.
3 is the same as 4, isn't it. you modify a header field by creating
a delete lump refering the old value and an insert lump with the new
value. the new value must be created using pkg_malloc. the replace
action in textops module is a good example. (The lump lists, sort
of "diffs", is processed when later on the message is printed and forwarded.)
-Jiri