log: fsm: allow logging the timeout on state change

Add a flag that adds timeout info to osmo_fsm_inst state change logging.

To not affect unit testing, make this an opt-in feature that is disabled by
default -- mostly because osmo_fsm_inst_state_chg_keep_timer() will produce
non-deterministic logging depending on timing (logs remaining time).

Unit tests that don't verify log output and those that use fake time may also
enable this feature. Do so in fsm_test.c.

The idea is that in due course we will add osmo_fsm_log_timeouts(true) calls to
all of our production applications' main() initialization.

Change-Id: I089b81021a1a4ada1205261470da032b82d57872

2 files changed, 13 insertions, 10 deletions

diff --git a/tests/fsm/fsm_test.c b/tests/fsm/fsm_test.c
index 7aac8d3e..f8ebdc7b 100644
--- a/tests/fsm/fsm_test.c
+++ b/tests/fsm/fsm_test.c
@@ -406,6 +406,9 @@ int main(int argc, char **argv)
 
 	osmo_fsm_log_addr(false);
 
+	/* Using fake time to get deterministic timeout logging */
+	osmo_fsm_log_timeouts(true);
+
 	log_init(&log_info, NULL);
 	stderr_target = log_target_create_stderr();
 	log_add_target(stderr_target);
diff --git a/tests/fsm/fsm_test.err b/tests/fsm/fsm_test.err
index bf474aba..13cbacd9 100644
--- a/tests/fsm/fsm_test.err
+++ b/tests/fsm/fsm_test.err
@@ -3,9 +3,9 @@ Checking FSM allocation
 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){NULL}: State change to ONE (no timeout)
 Test_FSM(my_id){ONE}: Received Event EV_B
-Test_FSM(my_id){ONE}: state_chg to TWO
+Test_FSM(my_id){ONE}: State change to TWO (T2342, 1s)
 Test_FSM(my_id){TWO}: Timeout of T2342
 Timer
 Test_FSM(my_id){TWO}: Deallocated
@@ -83,16 +83,16 @@ Test_FSM(arbitrary_id){NULL}: Terminating (cause = OSMO_FSM_TERM_REQUEST)
 
 --- test_state_chg_keep_timer()
 Test_FSM{NULL}: Allocated
-Test_FSM{NULL}: state_chg to ONE
-Test_FSM{ONE}: state_chg to TWO
+Test_FSM{NULL}: State change to ONE (no timeout)
+Test_FSM{ONE}: State change to TWO (no timeout)
 Test_FSM{TWO}: Terminating (cause = OSMO_FSM_TERM_REQUEST)
 Test_FSM{TWO}: Freeing instance
 Test_FSM{TWO}: Deallocated
 Total time passed: 0.000000 s
 Test_FSM{NULL}: Allocated
-Test_FSM{NULL}: state_chg to ONE
+Test_FSM{NULL}: State change to ONE (T10, 10s)
 Total time passed: 2.000342 s
-Test_FSM{ONE}: state_chg to TWO
+Test_FSM{ONE}: State change to TWO (keeping T10, 7.999s remaining)
 Total time passed: 2.000342 s
 Total time passed: 9.999999 s
 Total time passed: 10.000000 s
@@ -104,14 +104,14 @@ Test_FSM{TWO}: Timeout of T10
 
 --- test_state_chg_T()
 Test_FSM{NULL}: Allocated
-Test_FSM{NULL}: state_chg to ONE
-Test_FSM{ONE}: state_chg to TWO
+Test_FSM{NULL}: State change to ONE (T42, 23s)
+Test_FSM{ONE}: State change to TWO (no timeout)
 Test_FSM{TWO}: Terminating (cause = OSMO_FSM_TERM_REQUEST)
 Test_FSM{TWO}: Freeing instance
 Test_FSM{TWO}: Deallocated
 Test_FSM{NULL}: Allocated
-Test_FSM{NULL}: state_chg to ONE
-Test_FSM{ONE}: state_chg to TWO
+Test_FSM{NULL}: State change to ONE (T42, 23s)
+Test_FSM{ONE}: State change to TWO (no timeout)
 Test_FSM{TWO}: Terminating (cause = OSMO_FSM_TERM_REQUEST)
 Test_FSM{TWO}: Freeing instance
 Test_FSM{TWO}: Deallocated