mgcp/rtp: Add counter for invalid RTP timestamp deltas
This patch modifies the patch_and_count() function to check for RTP
timestamp inconsistencies. It basically checks, whether dTS/dSeqNo
remains constant. If this fails, the corresponding counter is
incremented. There are four counter for this: Incoming and outgoing,
each for streams from the BTS and the net.
Note that this approach presumes, that the per RTP packet duration
(in samples) remains the same throughout the entire stream. Changing
the number of speech frames per channel and packet will be detected
as error.
In addition, the VTY command 'show mgcp' is extended by an optional
'stats' to show the counter values, too.
Ticket: OW#964
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/libmgcp/mgcp_protocol.c b/openbsc/src/libmgcp/mgcp_protocol.c
index 616e0a9..aec2cb0 100644
--- a/openbsc/src/libmgcp/mgcp_protocol.c
+++ b/openbsc/src/libmgcp/mgcp_protocol.c
@@ -1163,14 +1163,30 @@
{
uint32_t expected, jitter;
int ploss;
+ int nchars;
mgcp_state_calc_loss(&endp->net_state, &endp->net_end,
&expected, &ploss);
jitter = mgcp_state_calc_jitter(&endp->net_state);
- snprintf(msg, size, "\r\nP: PS=%u, OS=%u, PR=%u, OR=%u, PL=%d, JI=%u",
- endp->bts_end.packets, endp->bts_end.octets,
- endp->net_end.packets, endp->net_end.octets,
- ploss, jitter);
+ nchars = snprintf(msg, size,
+ "\r\nP: PS=%u, OS=%u, PR=%u, OR=%u, PL=%d, JI=%u",
+ endp->bts_end.packets, endp->bts_end.octets,
+ endp->net_end.packets, endp->net_end.octets,
+ ploss, jitter);
+ if (nchars < 0 || nchars >= size)
+ goto truncate;
+
+ msg += nchars;
+ size -= nchars;
+
+ /* Error Counter */
+ snprintf(msg, size,
+ "\r\nX-Osmo-CP: EC TIS=%u, TOS=%u, TIR=%u, TOR=%u",
+ endp->net_state.in_stream.err_ts_counter,
+ endp->net_state.out_stream.err_ts_counter,
+ endp->bts_state.in_stream.err_ts_counter,
+ endp->bts_state.out_stream.err_ts_counter);
+truncate:
msg[size - 1] = '\0';
}