[bssap] Start to queue messages to the BTS and to the MSC

For the MSC we need to queue GSM04.08 messages until the
SCCP connection is  confirmed to be open and then can send
the stored messages. The queue is limited to 10 messages
at which point new ones will be dropped. Currently the
only messages we get are measurement indication messages
but it is better to be safe than sorry.

The SCCP messages are sent as soon as the connection
is considered established and then no queueing happens
any more. While replacing sccp_connection_write calls
various memory leaks has been fixed.

For the MS we might have received a DTAP and need to do
an operation that requires a roundtrip and want to send
wait until this has happened. The two scenerios are sending
a SMS to the phone that requires to do something special
for the different SAPI. Currently it is assumed that
only one SAPI=0 -> SAPI=3 change happen during the connection.

For the first SAPI != 0 we will send the rll_ request
and then wait for the timeout or confirmation. In case
of timeout a SAPI "n" reject is sent and in case of
success the queue is getting emptied.

1 files changed, 8 insertions, 0 deletions

diff --git a/openbsc/include/openbsc/bssap.h b/openbsc/include/openbsc/bssap.h
index 1db026525..d6553409a 100644
--- a/openbsc/include/openbsc/bssap.h
+++ b/openbsc/include/openbsc/bssap.h
@@ -278,4 +278,12 @@ struct msgb *bssmap_create_sapi_reject(u_int8_t link_id);
 int dtap_rcvmsg(struct gsm_lchan *lchan, struct msgb *msg, unsigned int length);
 struct msgb *dtap_create_msg(struct msgb *msg_l3, u_int8_t link_id);
 
+void bsc_queue_connection_write(struct sccp_connection *conn, struct msgb *msg);
+void bsc_free_queued(struct sccp_connection *conn);
+void bsc_send_queued(struct sccp_connection *conn);
+
+void bts_queue_send(struct msgb *msg, int link_id);
+void bts_send_queued(struct bss_sccp_connection_data*);
+void bts_free_queued(struct bss_sccp_connection_data*);
+
 #endif