unify allocation of gsm_subscriber_connection

The current msc_subscr_con_allocate() was in fact only used by msc_vlr_tests,
while both a_iface_bssap.c and iucs.c did their own duplicate code of
allocating the gsm_subscriber_connection struct. Unify.

Drop the old msc_subscr_con_allocate(), instead add msc_subscr_conn_alloc().
The new function also takes via_ran and lac arguments directly.

The conn allocation will soon be closely tied to the subscr_conn_fsm instance
allocation, so place the new function definition alongside the other
subscr_conn_fsm API, and match its naming ("conn").

Related: OS#3122
Change-Id: Ia57b42a149a43f9c370b1310e2e1f512183993ea

3 files changed, 22 insertions, 12 deletions

diff --git a/src/libmsc/a_iface_bssap.c b/src/libmsc/a_iface_bssap.c
index 743814cd3..1665e2307 100644
--- a/src/libmsc/a_iface_bssap.c
+++ b/src/libmsc/a_iface_bssap.c
@@ -54,14 +54,10 @@ static struct gsm_subscriber_connection *subscr_conn_allocate_a(const struct a_c
 
 	LOGP(DMSC, LOGL_DEBUG, "Allocating A-Interface subscriber conn: lac %i, conn_id %i\n", lac, conn_id);
 
-	conn = talloc_zero(network, struct gsm_subscriber_connection);
+	conn = msc_subscr_conn_alloc(network, RAN_GERAN_A, lac);
 	if (!conn)
 		return NULL;
 
-	conn->network = network;
-	conn->via_ran = RAN_GERAN_A;
-	conn->lac = lac;
-
 	conn->a.conn_id = conn_id;
 	conn->a.scu = scu;
 
@@ -69,7 +65,6 @@ static struct gsm_subscriber_connection *subscr_conn_allocate_a(const struct a_c
 	 * identify later which BSC is responsible for this subscriber connection */
 	memcpy(&conn->a.bsc_addr, &a_conn_info->bsc->bsc_addr, sizeof(conn->a.bsc_addr));
 
-	llist_add_tail(&conn->entry, &network->subscr_conns);
 	LOGPCONN(conn, LOGL_DEBUG, "A-Interface subscriber connection successfully allocated!\n");
 	return conn;
 }
diff --git a/src/libmsc/iucs.c b/src/libmsc/iucs.c
index d6da1f795..a3092f86e 100644
--- a/src/libmsc/iucs.c
+++ b/src/libmsc/iucs.c
@@ -57,17 +57,12 @@ static struct gsm_subscriber_connection *subscr_conn_allocate_iu(struct gsm_netw
 	DEBUGP(DIUCS, "Allocating IuCS subscriber conn: lac %d, conn_id %" PRIx32 "\n",
 	       lac, ue->conn_id);
 
-	conn = talloc_zero(network, struct gsm_subscriber_connection);
+	conn = msc_subscr_conn_alloc(network, RAN_UTRAN_IU, lac);
 	if (!conn)
 		return NULL;
 
-	conn->network = network;
-	conn->via_ran = RAN_UTRAN_IU;
 	conn->iu.ue_ctx = ue;
 	conn->iu.ue_ctx->rab_assign_addr_enc = network->iu.rab_assign_addr_enc;
-	conn->lac = lac;
-
-	llist_add_tail(&conn->entry, &network->subscr_conns);
 	return conn;
 }
 
diff --git a/src/libmsc/subscr_conn.c b/src/libmsc/subscr_conn.c
index fc89a663f..5629d26f9 100644
--- a/src/libmsc/subscr_conn.c
+++ b/src/libmsc/subscr_conn.c
@@ -369,6 +369,26 @@ void msc_subscr_conn_init(void)
 	osmo_fsm_register(&subscr_conn_fsm);
 }
 
+/* Allocate a new subscriber conn. */
+struct gsm_subscriber_connection *msc_subscr_conn_alloc(struct gsm_network *network,
+							enum ran_type via_ran, uint16_t lac)
+{
+	struct gsm_subscriber_connection *conn;
+
+	conn = talloc_zero(network, struct gsm_subscriber_connection);
+	if (!conn)
+		return NULL;
+
+	*conn = (struct gsm_subscriber_connection){
+		.network = network,
+		.via_ran = via_ran,
+		.lac = lac,
+	};
+
+	llist_add_tail(&conn->entry, &network->subscr_conns);
+	return conn;
+}
+
 const struct value_string complete_layer3_type_names[] = {
 	{ COMPLETE_LAYER3_NONE, "NONE" },
 	{ COMPLETE_LAYER3_LU, "LU" },