rspro_client_fsm: Make RSPRO transmit use FSM event

This way we can easily guarantee that RSPRO transmit will only happen
in the fully established state, and that violations of that rule will
generate error logs by means of osmo_fsm core logging code.

Change-Id: I3c403507fa11c068d7503107857fbd5676ce135f

src/rspro_client_fsm.c

@@ -77,6 +77,12 @@ int ipa_client_conn_send_rspro(struct ipa_client_conn *ipa, RsproPDU_t *rspro)
 	return 0;
 }
 
+static int _server_conn_send_rspro(struct rspro_server_conn *srvc, RsproPDU_t *rspro)
+{
+	LOGPFSM(srvc->fi, "Tx RSPRO %s\n", rspro_msgt_name(rspro));
+	return ipa_client_conn_send_rspro(srvc->conn, rspro);
+}
+
 int server_conn_send_rspro(struct rspro_server_conn *srvc, RsproPDU_t *rspro)
 {
 	if (!rspro) {
@@ -84,8 +90,11 @@ int server_conn_send_rspro(struct rspro_server_conn *srvc, RsproPDU_t *rspro)
 		osmo_log_backtrace(DMAIN, LOGL_ERROR);
 		return -EINVAL;
 	}
-	LOGPFSM(srvc->fi, "Tx RSPRO %s\n", rspro_msgt_name(rspro));
-	return ipa_client_conn_send_rspro(srvc->conn, rspro);
+	if (osmo_fsm_inst_dispatch(srvc->fi, SRVC_E_RSPRO_TX, rspro) < 0) {
+		ASN_STRUCT_FREE(asn_DEF_RsproPDU, rspro);
+		return -EPERM;
+	}
+	return 0;
 }
 
 enum server_conn_fsm_state {
@@ -105,6 +114,7 @@ static const struct value_string server_conn_fsm_event_names[] = {
 	OSMO_VALUE_STRING(SRVC_E_TCP_DOWN),
 	OSMO_VALUE_STRING(SRVC_E_KA_TIMEOUT),
 	OSMO_VALUE_STRING(SRVC_E_CLIENT_CONN_RES),
+	OSMO_VALUE_STRING(SRVC_E_RSPRO_TX),
 	{ 0, NULL }
 };
 
@@ -202,7 +212,7 @@ static void srvc_st_established_onenter(struct osmo_fsm_inst *fi, uint32_t prev_
 	else
 		pdu = rspro_gen_ConnectBankReq(&srvc->own_comp_id, srvc->bankd.bank_id,
 					       srvc->bankd.num_slots);
-	server_conn_send_rspro(srvc, pdu);
+	_server_conn_send_rspro(srvc, pdu);
 }
 
 static void srvc_st_established(struct osmo_fsm_inst *fi, uint32_t event, void *data)
@@ -234,11 +244,18 @@ static void srvc_st_established(struct osmo_fsm_inst *fi, uint32_t event, void *
 
 static void srvc_st_connected(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 {
+	struct rspro_server_conn *srvc = (struct rspro_server_conn *) fi->priv;
+	RsproPDU_t *pdu = NULL;
+
 	switch (event) {
 	case SRVC_E_TCP_DOWN:
 	case SRVC_E_KA_TIMEOUT:
 		osmo_fsm_inst_state_chg(fi, SRVC_ST_REESTABLISH, T2_RECONNECT, 2);
 		break;
+	case SRVC_E_RSPRO_TX:
+		pdu = data;
+		_server_conn_send_rspro(srvc, pdu);
+		break;
 	default:
 		OSMO_ASSERT(0);
 	}
@@ -350,7 +367,7 @@ static const struct osmo_fsm_state server_conn_fsm_states[] = {
 	},
 	[SRVC_ST_CONNECTED] = {
 		.name = "CONNECTED",
-		.in_event_mask = S(SRVC_E_TCP_DOWN) | S(SRVC_E_KA_TIMEOUT),
+		.in_event_mask = S(SRVC_E_TCP_DOWN) | S(SRVC_E_KA_TIMEOUT) | S(SRVC_E_RSPRO_TX),
 		.out_state_mask = S(SRVC_ST_REESTABLISH),
 		.action = srvc_st_connected,
 	},

src/rspro_client_fsm.h

@@ -10,6 +10,7 @@ enum server_conn_fsm_event {
 	SRVC_E_TCP_DOWN,
 	SRVC_E_KA_TIMEOUT,
 	SRVC_E_CLIENT_CONN_RES,
+	SRVC_E_RSPRO_TX		/* transmit a RSPRO PDU to the peer */
 };
 
 struct rspro_server_conn;