nat: We want the remote to respond to our DLCX request

We want to send a TRAP with the MGCP statistics from the NAT and
the connected BSC. The BSC endpoint can be either released because
of a DLCX from the MGCP CallAgent or the SCCP Connection release on
the A-link.

This is why we need to queue the statistics when the deleting the
endpoint on the BSC. The processing is continued once the response
arrives. This code assumes that the response of the DLCX will be sent
by the remote side. The current amount of outstanding responses can be
seen on the VTY. This assumption is based on the fact that the BSC has
already responded to the CRCX and maybe to the MDCX.

The MGCP RFC is bended to prefix the transaction identifier with "nat-"
to easily detect the response and hand it to the handler. This will
then parse the response and generate the TRAP. The current version is
v1. We assume that the transaction space is big enough and we will
not re-assign the transaction identifier too early.

1 files changed, 29 insertions, 1 deletions

diff --git a/openbsc/src/libmgcp/mgcp_protocol.c b/openbsc/src/libmgcp/mgcp_protocol.c
index 6919a591d..dc5e0f992 100644
--- a/openbsc/src/libmgcp/mgcp_protocol.c
+++ b/openbsc/src/libmgcp/mgcp_protocol.c
@@ -1167,9 +1167,37 @@ void mgcp_format_stats(struct mgcp_endpoint *endp, char *msg, size_t size)
 				&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=%d",
+	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);
 	msg[size - 1] = '\0';
 }
+
+int mgcp_parse_stats(struct msgb *msg, uint32_t *ps, uint32_t *os,
+		uint32_t *pr, uint32_t *_or, int *loss, uint32_t *jitter)
+{
+	char *line, *save;
+	int rc;
+
+	/* initialize with bad values */
+	*ps = *os = *pr = *_or = *jitter = UINT_MAX;
+	*loss = INT_MAX;
+
+
+	line = strtok_r((char *) msg->l2h, "\r\n", &save);
+	if (!line)
+		return -1;
+
+	/* this can only parse the message that is created above... */
+	for_each_line(line, save) {
+		switch (line[0]) {
+		case 'P':
+			rc = sscanf(line, "P: PS=%u, OS=%u, PR=%u, OR=%u, PL=%d, JI=%u",
+					ps, os, pr, _or, loss, jitter);
+			return rc == 6 ? 0 : -1;
+		}
+	}
+
+	return -1;
+}