I recently came across a problem that manifested only on Fedora 20 and Mint
(not on Ubunto or Centos 6.x). When using SIPTAG_PAYLOAD_STR to add a body to
an outgoing SIP message, the message goes out without any body; i.e., it's as
if that tag was silently ignored. My program would also subsquently crash.
Again, this problem was only experienced on certain Linux distros
I eventually tracked it to this code in the msg_hclass_offset function in
msg_parser.c.
else
/* Header has no name. */
for (i = 0; i <= 6; i++)
if (hc->hc_hash == mc->mc_request[i].hr_class->hc_hash)
return (msg_header_t **)((char *)mo + mc->mc_request[i].hr_offset);
Something in that non-standard way of iterating through the msg_href_t elements
in the msg_mclass_s structure was causing weird results. When I stepped
through the code, which is supposed to iterate across the bolded elements in
the struct below (you can see that I call it "non-standard" because it is
incrementing across an array that has only one member, but using that as a
device to check each of the 6 members) what I saw was that an incorrect match
was returned, and thus the offset to the sip_payload_t member which this
function returns was incorrect. Hence the bad things happened.
struct msg_mclass_s
{
struct msg_hclass_s
mc_hclass[1]; /**< Recursive header class */
char const *mc_name; /**< Protocol name, e.g., "SIP/2.0" */
void *mc_tag; /**< Protocol-specific tag */
unsigned mc_flags; /**< Default flags */
unsigned mc_msize; /**< Size of public message structure */
/** Function extracting the message contents. */
issize_t (*mc_extract_body)(msg_t *msg, msg_pub_t *pub,
char b[], isize_t bsiz, int eos);
msg_href_t mc_request[1]; /**< Request line reference */
msg_href_t mc_status[1]; /**< Status line reference */
msg_href_t mc_separator[1];/**< Separator line reference */
msg_href_t mc_payload[1]; /**< Message body reference */
msg_href_t mc_unknown[1]; /**< Reference for unknown headers */
msg_href_t mc_error[1]; /**< Reference for erroneous header */
msg_href_t mc_multipart[1];/**< Multipart body reference */
msg_href_t const *
mc_short; /**< Short forms (or NULL) */
short mc_hash_size; /**< Size of parsing table */
short mc_hash_used; /**< Number of headers in parsing table */
/** Hash table for parsing containing reference for each header. */
msg_href_t mc_hash[MC_HASH_SIZE];
};
Here is my commit that fixed things in my public repo:
https://github.com/davehorton/sofia-sip/commit/51bb86448d952a5997a8d7e38c545c164fa112a2
Dave------------------------------------------------------------------------------
Start Your Social Network Today - Download eXo Platform
Build your Enterprise Intranet with eXo Platform Software
Java Based Open Source Intranet - Social, Extensible, Cloud Ready
Get Started Now And Turn Your Intranet Into A Collaboration Platform
http://p.sf.net/sfu/ExoPlatform
_______________________________________________
Sofia-sip-devel mailing list
Sofia-sip-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sofia-sip-devel
