print BIG FAT ERROR message if osmo_fsm lacks event names

Event names are displayed in VTY commands so all FSM should have them.
Print an error message if an FSM is registered without event names.
We could also return an error code, however at present no caller checks
the return value of osmo_fsm_register() so this would be pointless.

Add event names to the test FSM and update expected output accordingly.

Change-Id: I08b100d62b5c50bf025ef87d31ea39072539cf37
Related: OS#3008

3 files changed, 13 insertions, 4 deletions

diff --git a/src/fsm.c b/src/fsm.c
index 176aa8ab..342542fb 100644
--- a/src/fsm.c
+++ b/src/fsm.c
@@ -154,6 +154,8 @@ int osmo_fsm_register(struct osmo_fsm *fsm)
 	}
 	if (osmo_fsm_find_by_name(fsm->name))
 		return -EEXIST;
+	if (fsm->event_names == NULL)
+		LOGP(DLGLOBAL, LOGL_ERROR, "FSM '%s' has no event names! Please fix!\n", fsm->name);
 	llist_add_tail(&fsm->list, &osmo_g_fsms);
 	INIT_LLIST_HEAD(&fsm->instances);
 
diff --git a/tests/fsm/fsm_test.c b/tests/fsm/fsm_test.c
index 3bcb7d49..f70b0b5c 100644
--- a/tests/fsm/fsm_test.c
+++ b/tests/fsm/fsm_test.c
@@ -28,6 +28,12 @@ enum test_fsm_evt {
 	EV_B,
 };
 
+static const struct value_string test_fsm_event_names[] = {
+	OSMO_VALUE_STRING(EV_A),
+	OSMO_VALUE_STRING(EV_B),
+	{ 0, NULL }
+};
+
 static void test_fsm_null(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 {
 	switch (event) {
@@ -88,6 +94,7 @@ static struct osmo_fsm fsm = {
 	.states = test_fsm_states,
 	.num_states = ARRAY_SIZE(test_fsm_states),
 	.log_subsys = DMAIN,
+	.event_names = test_fsm_event_names,
 };
 
 static struct ctrl_handle *g_ctrl;
diff --git a/tests/fsm/fsm_test.err b/tests/fsm/fsm_test.err
index 17a2f2e0..153963fc 100644
--- a/tests/fsm/fsm_test.err
+++ b/tests/fsm/fsm_test.err
@@ -1,10 +1,10 @@
 Checking FSM allocation
 Test_FSM(my_id){NULL}: Allocated
-Test_FSM(my_id){NULL}: Received Event 1
-Test_FSM(my_id){NULL}: Event 1 not permitted
-Test_FSM(my_id){NULL}: Received Event 0
+Test_FSM(my_id){NULL}: Received Event EV_B
+Test_FSM(my_id){NULL}: Event EV_B not permitted
+Test_FSM(my_id){NULL}: Received Event EV_A
 Test_FSM(my_id){NULL}: state_chg to ONE
-Test_FSM(my_id){ONE}: Received Event 1
+Test_FSM(my_id){ONE}: Received Event EV_B
 Test_FSM(my_id){ONE}: state_chg to TWO
 Test_FSM(my_id){TWO}: Timeout of T2342
 Timer