add osmo_fsm_set_dealloc_ctx(), to help with use-after-free

This is a simpler and more general solution to the problem so far solved by
osmo_fsm_term_safely(true). This extends use-after-free fixes to arbitrary
functions, not only FSM instances during termination.

The aim is to defer talloc_free() until back in the main loop.

Rationale: I discovered an osmo-msc use-after-free crash from an invalid
message, caused by this pattern:

void event_action()
{
       osmo_fsm_inst_dispatch(foo, FOO_EVENT, NULL);
       osmo_fsm_inst_dispatch(bar, BAR_EVENT, NULL);
}

Usually, FOO_EVENT takes successful action, and afterwards we also notify bar.
However, in this particular case, FOO_EVENT caused failure, and the immediate
error handling directly terminated and deallocated bar. In such a case,
dispatching BAR_EVENT causes a use-after-free; this constituted a DoS vector
just from sending messages that cause *any* failure during the first event
dispatch.

Instead, when this is enabled, we do not deallocate 'foo' until event_action()
has returned back to the main loop.

Test: duplicate fsm_dealloc_test.c using this, and print the number of items
deallocated in each test loop, to ensure the feature works. We also verify that
the deallocation safety works simply by fsm_dealloc_test.c not crashing.

We should probably follow up by refusing event dispatch and state transitions
for FSM instances that are terminating or already terminated:
see I0adc13a1a998e953b6c850efa2761350dd07e03a.

Change-Id: Ief4dba9ea587c9b4aea69993e965fbb20fb80e78

2 files changed, 3460 insertions, 17 deletions

diff --git a/tests/fsm/fsm_dealloc_test.c b/tests/fsm/fsm_dealloc_test.c
index ce492056..9a6974d9 100644
--- a/tests/fsm/fsm_dealloc_test.c
+++ b/tests/fsm/fsm_dealloc_test.c
@@ -355,7 +355,7 @@ void obj_term(struct obj *obj)
 	osmo_fsm_inst_term(obj->fi, OSMO_FSM_TERM_REGULAR, NULL);
 }
 
-void test_dealloc(enum objname trigger, bool by_destroy_event)
+void test_dealloc(enum objname trigger, bool by_destroy_event, void *loop_ctx)
 {
 	struct scene *s = scene_alloc();
 	const char *label = by_destroy_event ? "destroy-event" : "term";
@@ -383,16 +383,63 @@ void test_dealloc(enum objname trigger, bool by_destroy_event)
 		LOGP(DLGLOBAL, LOGL_DEBUG, "--- %d objects remain. cleaning up\n", remain);
 	} else
 		LOGP(DLGLOBAL, LOGL_DEBUG, "--- all deallocated.\n");
+
+	if (loop_ctx) {
+		fprintf(stderr, "*** loop_ctx contains %zu blocks, deallocating.\n",
+			talloc_total_blocks(loop_ctx));
+		talloc_free_children(loop_ctx);
+	}
+
+	/* Silently free the remaining objects. */
 	scene_clean(s);
+	if (loop_ctx)
+		talloc_free_children(loop_ctx);
 }
 
-int main(void)
+static void trigger_tests(void *loop_ctx)
 {
-	enum objname trigger;
 	size_t ctx_blocks;
 	size_t ctx_size;
+	enum objname trigger;
 	int by_destroy_event;
 
+	ctx_blocks = talloc_total_blocks(ctx);
+	ctx_size = talloc_total_size(ctx);
+
+	for (trigger = 0; trigger < scene_size; trigger++) {
+		for (by_destroy_event = 0; by_destroy_event < 2; by_destroy_event++) {
+			test_dealloc(trigger, (bool)by_destroy_event, loop_ctx);
+
+			if (ctx_blocks != talloc_total_blocks(ctx)
+			    || ctx_size != talloc_total_size(ctx)) {
+				talloc_report_full(ctx, stderr);
+				OSMO_ASSERT(false);
+			}
+		}
+	}
+}
+
+void test_osmo_fsm_term_safely()
+{
+	fprintf(stderr, "\n\n%s()\n", __func__);
+	osmo_fsm_term_safely(true);
+	trigger_tests(NULL);
+	osmo_fsm_term_safely(false);
+	fprintf(stderr, "\n\n%s() done\n", __func__);
+}
+
+void test_osmo_fsm_set_dealloc_ctx()
+{
+	fprintf(stderr, "\n\n%s()\n", __func__);
+	void *dealloc_ctx = talloc_named_const(ctx, 0, "fsm_dealloc");
+	osmo_fsm_set_dealloc_ctx(dealloc_ctx);
+	trigger_tests(dealloc_ctx);
+	osmo_fsm_set_dealloc_ctx(NULL);
+	fprintf(stderr, "\n\n%s() done\n", __func__);
+}
+
+int main(void)
+{
 	ctx = talloc_named_const(NULL, 0, "main");
 	osmo_init_logging2(ctx, NULL);
 
@@ -405,22 +452,10 @@ int main(void)
 
 	log_set_category_filter(osmo_stderr_target, DLGLOBAL, 1, LOGL_DEBUG);
 
-	osmo_fsm_term_safely(true);
 	osmo_fsm_register(&test_fsm);
 
-	ctx_blocks = talloc_total_blocks(ctx);
-	ctx_size = talloc_total_size(ctx);
-
-	for (trigger = 0; trigger < scene_size; trigger++) {
-		for (by_destroy_event = 0; by_destroy_event < 2; by_destroy_event++) {
-			test_dealloc(trigger, (bool)by_destroy_event);
-			if (ctx_blocks != talloc_total_blocks(ctx)
-			    || ctx_size != talloc_total_size(ctx)) {
-				talloc_report_full(ctx, stderr);
-				OSMO_ASSERT(false);
-			}
-		}
-	}
+	test_osmo_fsm_term_safely();
+	test_osmo_fsm_set_dealloc_ctx();
 
 	talloc_free(ctx);
 	return 0;
diff --git a/tests/fsm/fsm_dealloc_test.err b/tests/fsm/fsm_dealloc_test.err
index d12c5aa3..973f3d42 100644
--- a/tests/fsm/fsm_dealloc_test.err
+++ b/tests/fsm/fsm_dealloc_test.err
@@ -1,3 +1,6 @@
+
+
+test_osmo_fsm_term_safely()
 DLGLOBAL DEBUG scene_alloc()
 DLGLOBAL DEBUG test(root){alive}: Allocated
 DLGLOBAL DEBUG test(root){alive}: Allocated
@@ -3250,3 +3253,3408 @@ DLGLOBAL DEBUG test(other){alive}: Deallocated, including all deferred deallocat
 DLGLOBAL DEBUG 0 (-)
 DLGLOBAL DEBUG --- after destroy-event cascade:
 DLGLOBAL DEBUG --- all deallocated.
+
+
+test_osmo_fsm_term_safely() done
+
+
+test_osmo_fsm_set_dealloc_ctx()
+DLGLOBAL DEBUG scene_alloc()
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: is child of test(root)
+DLGLOBAL DEBUG test(_branch0){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: is child of test(_branch0)
+DLGLOBAL DEBUG test(_branch0){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: is child of test(_branch0)
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: is child of test(root)
+DLGLOBAL DEBUG test(_branch1){alive}: Allocated
+DLGLOBAL DEBUG test(_branch1){alive}: is child of test(_branch1)
+DLGLOBAL DEBUG test(_branch1){alive}: Allocated
+DLGLOBAL DEBUG test(_branch1){alive}: is child of test(_branch1)
+DLGLOBAL DEBUG test(other){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: _branch0.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[0] = _branch0
+DLGLOBAL DEBUG test(__twig0a){alive}: __twig0a.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[1] = __twig0a
+DLGLOBAL DEBUG test(_branch1){alive}: _branch1.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[1] = _branch1
+DLGLOBAL DEBUG test(__twig1a){alive}: __twig1a.other[0] = root
+DLGLOBAL DEBUG test(root){alive}: root.other[0] = __twig1a
+DLGLOBAL DEBUG ------ before term cascade, got:
+DLGLOBAL DEBUG   root
+DLGLOBAL DEBUG   _branch0
+DLGLOBAL DEBUG   __twig0a
+DLGLOBAL DEBUG   __twig0b
+DLGLOBAL DEBUG   _branch1
+DLGLOBAL DEBUG   __twig1a
+DLGLOBAL DEBUG   __twig1b
+DLGLOBAL DEBUG   other
+DLGLOBAL DEBUG ---
+DLGLOBAL DEBUG --- term at root
+DLGLOBAL DEBUG test(root){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(root){alive}: pre_term()
+DLGLOBAL DEBUG test(_branch1){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(_branch1){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1b){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig1b){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1b){alive}: Removing from parent test(_branch1)
+DLGLOBAL DEBUG 1 (__twig1b.cleanup())
+DLGLOBAL DEBUG test(__twig1b){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig1b){alive}: scene forgets __twig1b
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 2 (__twig1b.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 3 (__twig1b.cleanup(),_branch1.alive(),_branch1.child_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_CHILD_GONE: Dropped reference _branch1.child[1] = __twig1b
+DLGLOBAL DEBUG test(_branch1){alive}: still exists: child[0]
+DLGLOBAL DEBUG 2 (__twig1b.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG 1 (__twig1b.cleanup())
+DLGLOBAL DEBUG test(__twig1b){alive}: cleanup() done
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG test(__twig1b){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig1b){alive}: Deallocated
+DLGLOBAL DEBUG test(__twig1a){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig1a){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1a){alive}: Removing from parent test(_branch1)
+DLGLOBAL DEBUG 1 (__twig1a.cleanup())
+DLGLOBAL DEBUG test(__twig1a){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig1a){alive}: scene forgets __twig1a
+DLGLOBAL DEBUG test(__twig1a){alive}: removing reference __twig1a.other[0] -> root
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 2 (__twig1a.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 3 (__twig1a.cleanup(),root.alive(),root.other_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_OTHER_GONE: Dropped reference root.other[0] = __twig1a
+DLGLOBAL DEBUG 2 (__twig1a.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 1 (__twig1a.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 2 (__twig1a.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 3 (__twig1a.cleanup(),_branch1.alive(),_branch1.child_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_CHILD_GONE: Dropped reference _branch1.child[0] = __twig1a
+DLGLOBAL DEBUG test(_branch1){alive}: No more children
+DLGLOBAL DEBUG 2 (__twig1a.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 1 (__twig1a.cleanup())
+DLGLOBAL DEBUG test(__twig1a){alive}: cleanup() done
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG test(__twig1a){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig1a){alive}: Deallocated
+DLGLOBAL DEBUG test(_branch1){alive}: Removing from parent test(root)
+DLGLOBAL DEBUG 1 (_branch1.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: cleanup()
+DLGLOBAL DEBUG test(_branch1){alive}: scene forgets _branch1
+DLGLOBAL DEBUG test(_branch1){alive}: removing reference _branch1.other[0] -> other
+DLGLOBAL DEBUG test(other){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 2 (_branch1.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 3 (_branch1.cleanup(),other.alive(),other.other_gone())
+DLGLOBAL DEBUG test(other){alive}: EV_OTHER_GONE: Dropped reference other.other[1] = _branch1
+DLGLOBAL DEBUG 2 (_branch1.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(other){alive}: pre_term()
+DLGLOBAL DEBUG 3 (_branch1.cleanup(),other.alive(),other.cleanup())
+DLGLOBAL DEBUG test(other){alive}: cleanup()
+DLGLOBAL DEBUG test(other){alive}: scene forgets other
+DLGLOBAL DEBUG test(other){alive}: removing reference other.other[0] -> _branch0
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 4 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.other_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_OTHER_GONE: Dropped reference _branch0.other[0] = other
+DLGLOBAL DEBUG 4 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(_branch0){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0b){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig0b){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0b){alive}: Removing from parent test(_branch0)
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG test(__twig0b){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig0b){alive}: scene forgets __twig0b
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 7 (_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0b.cleanup(),_branch0.child_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_CHILD_GONE: Dropped reference _branch0.child[1] = __twig0b
+DLGLOBAL DEBUG test(_branch0){alive}: still exists: child[0]
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG test(__twig0b){alive}: cleanup() done
+DLGLOBAL DEBUG 4 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(__twig0b){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig0b){alive}: Deallocated
+DLGLOBAL DEBUG test(__twig0a){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig0a){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0a){alive}: Removing from parent test(_branch0)
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(__twig0a){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig0a){alive}: scene forgets __twig0a
+DLGLOBAL DEBUG test(__twig0a){alive}: removing reference __twig0a.other[0] -> other
+DLGLOBAL DEBUG test(other){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),2*other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(other){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 7 (_branch1.cleanup(),2*other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup(),other.other_gone())
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),2*other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 7 (_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0a.cleanup(),_branch0.child_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_CHILD_GONE: Dropped reference _branch0.child[0] = __twig0a
+DLGLOBAL DEBUG test(_branch0){alive}: No more children
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(__twig0a){alive}: cleanup() done
+DLGLOBAL DEBUG 4 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(__twig0a){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig0a){alive}: Deallocated
+DLGLOBAL DEBUG test(_branch0){alive}: Removing from parent test(root)
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: cleanup()
+DLGLOBAL DEBUG test(_branch0){alive}: scene forgets _branch0
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 7 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup(),root.alive(),root.child_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_CHILD_GONE: Dropped reference root.child[0] = _branch0
+DLGLOBAL DEBUG test(root){alive}: still exists: child[1]
+DLGLOBAL DEBUG 6 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup(),root.alive())
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: cleanup() done
+DLGLOBAL DEBUG 4 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: Freeing instance
+DLGLOBAL DEBUG test(_branch0){alive}: Deallocated
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 5 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG test(root){alive}: EV_CHILD_GONE with NULL data, must be a parent_term event. Ignore.
+DLGLOBAL DEBUG 4 (_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG 3 (_branch1.cleanup(),other.alive(),other.cleanup())
+DLGLOBAL DEBUG test(other){alive}: cleanup() done
+DLGLOBAL DEBUG 2 (_branch1.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: Freeing instance
+DLGLOBAL DEBUG test(other){alive}: Deallocated
+DLGLOBAL DEBUG 1 (_branch1.cleanup())
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 2 (_branch1.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 3 (_branch1.cleanup(),root.alive(),root.child_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_CHILD_GONE: Dropped reference root.child[1] = _branch1
+DLGLOBAL DEBUG test(root){alive}: No more children
+DLGLOBAL DEBUG 2 (_branch1.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 1 (_branch1.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: cleanup() done
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG test(_branch1){alive}: Freeing instance
+DLGLOBAL DEBUG test(_branch1){alive}: Deallocated
+DLGLOBAL DEBUG 1 (root.cleanup())
+DLGLOBAL DEBUG test(root){alive}: cleanup()
+DLGLOBAL DEBUG test(root){alive}: scene forgets root
+DLGLOBAL DEBUG test(root){alive}: cleanup() done
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG test(root){alive}: Freeing instance
+DLGLOBAL DEBUG test(root){alive}: Deallocated
+DLGLOBAL DEBUG --- after term cascade:
+DLGLOBAL DEBUG --- all deallocated.
+*** loop_ctx contains 33 blocks, deallocating.
+DLGLOBAL DEBUG scene_alloc()
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: is child of test(root)
+DLGLOBAL DEBUG test(_branch0){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: is child of test(_branch0)
+DLGLOBAL DEBUG test(_branch0){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: is child of test(_branch0)
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: is child of test(root)
+DLGLOBAL DEBUG test(_branch1){alive}: Allocated
+DLGLOBAL DEBUG test(_branch1){alive}: is child of test(_branch1)
+DLGLOBAL DEBUG test(_branch1){alive}: Allocated
+DLGLOBAL DEBUG test(_branch1){alive}: is child of test(_branch1)
+DLGLOBAL DEBUG test(other){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: _branch0.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[0] = _branch0
+DLGLOBAL DEBUG test(__twig0a){alive}: __twig0a.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[1] = __twig0a
+DLGLOBAL DEBUG test(_branch1){alive}: _branch1.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[1] = _branch1
+DLGLOBAL DEBUG test(__twig1a){alive}: __twig1a.other[0] = root
+DLGLOBAL DEBUG test(root){alive}: root.other[0] = __twig1a
+DLGLOBAL DEBUG ------ before destroy-event cascade, got:
+DLGLOBAL DEBUG   root
+DLGLOBAL DEBUG   _branch0
+DLGLOBAL DEBUG   __twig0a
+DLGLOBAL DEBUG   __twig0b
+DLGLOBAL DEBUG   _branch1
+DLGLOBAL DEBUG   __twig1a
+DLGLOBAL DEBUG   __twig1b
+DLGLOBAL DEBUG   other
+DLGLOBAL DEBUG ---
+DLGLOBAL DEBUG --- destroy-event at root
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_DESTROY
+DLGLOBAL DEBUG 1 (root.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_DESTROY)
+DLGLOBAL DEBUG test(root){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(root){alive}: pre_term()
+DLGLOBAL DEBUG test(_branch1){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(_branch1){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1b){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig1b){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1b){alive}: Removing from parent test(_branch1)
+DLGLOBAL DEBUG 2 (root.alive(),__twig1b.cleanup())
+DLGLOBAL DEBUG test(__twig1b){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig1b){alive}: scene forgets __twig1b
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 3 (root.alive(),__twig1b.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 4 (root.alive(),__twig1b.cleanup(),_branch1.alive(),_branch1.child_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_CHILD_GONE: Dropped reference _branch1.child[1] = __twig1b
+DLGLOBAL DEBUG test(_branch1){alive}: still exists: child[0]
+DLGLOBAL DEBUG 3 (root.alive(),__twig1b.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG 2 (root.alive(),__twig1b.cleanup())
+DLGLOBAL DEBUG test(__twig1b){alive}: cleanup() done
+DLGLOBAL DEBUG 1 (root.alive())
+DLGLOBAL DEBUG test(__twig1b){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig1b){alive}: Deallocated
+DLGLOBAL DEBUG test(__twig1a){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig1a){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1a){alive}: Removing from parent test(_branch1)
+DLGLOBAL DEBUG 2 (root.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(__twig1a){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig1a){alive}: scene forgets __twig1a
+DLGLOBAL DEBUG test(__twig1a){alive}: removing reference __twig1a.other[0] -> root
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 3 (2*root.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 4 (2*root.alive(),__twig1a.cleanup(),root.other_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_OTHER_GONE: Dropped reference root.other[0] = __twig1a
+DLGLOBAL DEBUG 3 (2*root.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(root){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 2 (root.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 3 (root.alive(),__twig1a.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 4 (root.alive(),__twig1a.cleanup(),_branch1.alive(),_branch1.child_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_CHILD_GONE: Dropped reference _branch1.child[0] = __twig1a
+DLGLOBAL DEBUG test(_branch1){alive}: No more children
+DLGLOBAL DEBUG 3 (root.alive(),__twig1a.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 2 (root.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(__twig1a){alive}: cleanup() done
+DLGLOBAL DEBUG 1 (root.alive())
+DLGLOBAL DEBUG test(__twig1a){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig1a){alive}: Deallocated
+DLGLOBAL DEBUG test(_branch1){alive}: Removing from parent test(root)
+DLGLOBAL DEBUG 2 (root.alive(),_branch1.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: cleanup()
+DLGLOBAL DEBUG test(_branch1){alive}: scene forgets _branch1
+DLGLOBAL DEBUG test(_branch1){alive}: removing reference _branch1.other[0] -> other
+DLGLOBAL DEBUG test(other){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 3 (root.alive(),_branch1.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 4 (root.alive(),_branch1.cleanup(),other.alive(),other.other_gone())
+DLGLOBAL DEBUG test(other){alive}: EV_OTHER_GONE: Dropped reference other.other[1] = _branch1
+DLGLOBAL DEBUG 3 (root.alive(),_branch1.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(other){alive}: pre_term()
+DLGLOBAL DEBUG 4 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup())
+DLGLOBAL DEBUG test(other){alive}: cleanup()
+DLGLOBAL DEBUG test(other){alive}: scene forgets other
+DLGLOBAL DEBUG test(other){alive}: removing reference other.other[0] -> _branch0
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 5 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.other_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_OTHER_GONE: Dropped reference _branch0.other[0] = other
+DLGLOBAL DEBUG 5 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(_branch0){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0b){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig0b){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0b){alive}: Removing from parent test(_branch0)
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG test(__twig0b){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig0b){alive}: scene forgets __twig0b
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 7 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 8 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0b.cleanup(),_branch0.child_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_CHILD_GONE: Dropped reference _branch0.child[1] = __twig0b
+DLGLOBAL DEBUG test(_branch0){alive}: still exists: child[0]
+DLGLOBAL DEBUG 7 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0b.cleanup())
+DLGLOBAL DEBUG test(__twig0b){alive}: cleanup() done
+DLGLOBAL DEBUG 5 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(__twig0b){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig0b){alive}: Deallocated
+DLGLOBAL DEBUG test(__twig0a){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig0a){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0a){alive}: Removing from parent test(_branch0)
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(__twig0a){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig0a){alive}: scene forgets __twig0a
+DLGLOBAL DEBUG test(__twig0a){alive}: removing reference __twig0a.other[0] -> other
+DLGLOBAL DEBUG test(other){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 7 (root.alive(),_branch1.cleanup(),2*other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(other){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 8 (root.alive(),_branch1.cleanup(),2*other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup(),other.other_gone())
+DLGLOBAL DEBUG 7 (root.alive(),_branch1.cleanup(),2*other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 7 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 8 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0a.cleanup(),_branch0.child_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_CHILD_GONE: Dropped reference _branch0.child[0] = __twig0a
+DLGLOBAL DEBUG test(_branch0){alive}: No more children
+DLGLOBAL DEBUG 7 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),2*_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),__twig0a.cleanup())
+DLGLOBAL DEBUG test(__twig0a){alive}: cleanup() done
+DLGLOBAL DEBUG 5 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(__twig0a){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig0a){alive}: Deallocated
+DLGLOBAL DEBUG test(_branch0){alive}: Removing from parent test(root)
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: cleanup()
+DLGLOBAL DEBUG test(_branch0){alive}: scene forgets _branch0
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 7 (2*root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 8 (2*root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup(),root.child_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_CHILD_GONE: Dropped reference root.child[0] = _branch0
+DLGLOBAL DEBUG test(root){alive}: still exists: child[1]
+DLGLOBAL DEBUG 7 (2*root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup())
+DLGLOBAL DEBUG 6 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive(),_branch0.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: cleanup() done
+DLGLOBAL DEBUG 5 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: Freeing instance
+DLGLOBAL DEBUG test(_branch0){alive}: Deallocated
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 6 (2*root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG test(root){alive}: EV_CHILD_GONE with NULL data, must be a parent_term event. Ignore.
+DLGLOBAL DEBUG 5 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG 4 (root.alive(),_branch1.cleanup(),other.alive(),other.cleanup())
+DLGLOBAL DEBUG test(other){alive}: cleanup() done
+DLGLOBAL DEBUG 3 (root.alive(),_branch1.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: Freeing instance
+DLGLOBAL DEBUG test(other){alive}: Deallocated
+DLGLOBAL DEBUG 2 (root.alive(),_branch1.cleanup())
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 3 (2*root.alive(),_branch1.cleanup())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 4 (2*root.alive(),_branch1.cleanup(),root.child_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_CHILD_GONE: Dropped reference root.child[1] = _branch1
+DLGLOBAL DEBUG test(root){alive}: No more children
+DLGLOBAL DEBUG 3 (2*root.alive(),_branch1.cleanup())
+DLGLOBAL DEBUG test(root){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 2 (root.alive(),_branch1.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: cleanup() done
+DLGLOBAL DEBUG 1 (root.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: Freeing instance
+DLGLOBAL DEBUG test(_branch1){alive}: Deallocated
+DLGLOBAL DEBUG 2 (root.alive(),root.cleanup())
+DLGLOBAL DEBUG test(root){alive}: cleanup()
+DLGLOBAL DEBUG test(root){alive}: scene forgets root
+DLGLOBAL DEBUG test(root){alive}: cleanup() done
+DLGLOBAL DEBUG 1 (root.alive())
+DLGLOBAL DEBUG test(root){alive}: Freeing instance
+DLGLOBAL DEBUG test(root){alive}: Deallocated
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG --- after destroy-event cascade:
+DLGLOBAL DEBUG --- all deallocated.
+*** loop_ctx contains 33 blocks, deallocating.
+DLGLOBAL DEBUG scene_alloc()
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: is child of test(root)
+DLGLOBAL DEBUG test(_branch0){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: is child of test(_branch0)
+DLGLOBAL DEBUG test(_branch0){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: is child of test(_branch0)
+DLGLOBAL DEBUG test(root){alive}: Allocated
+DLGLOBAL DEBUG test(root){alive}: is child of test(root)
+DLGLOBAL DEBUG test(_branch1){alive}: Allocated
+DLGLOBAL DEBUG test(_branch1){alive}: is child of test(_branch1)
+DLGLOBAL DEBUG test(_branch1){alive}: Allocated
+DLGLOBAL DEBUG test(_branch1){alive}: is child of test(_branch1)
+DLGLOBAL DEBUG test(other){alive}: Allocated
+DLGLOBAL DEBUG test(_branch0){alive}: _branch0.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[0] = _branch0
+DLGLOBAL DEBUG test(__twig0a){alive}: __twig0a.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[1] = __twig0a
+DLGLOBAL DEBUG test(_branch1){alive}: _branch1.other[0] = other
+DLGLOBAL DEBUG test(other){alive}: other.other[1] = _branch1
+DLGLOBAL DEBUG test(__twig1a){alive}: __twig1a.other[0] = root
+DLGLOBAL DEBUG test(root){alive}: root.other[0] = __twig1a
+DLGLOBAL DEBUG ------ before term cascade, got:
+DLGLOBAL DEBUG   root
+DLGLOBAL DEBUG   _branch0
+DLGLOBAL DEBUG   __twig0a
+DLGLOBAL DEBUG   __twig0b
+DLGLOBAL DEBUG   _branch1
+DLGLOBAL DEBUG   __twig1a
+DLGLOBAL DEBUG   __twig1b
+DLGLOBAL DEBUG   other
+DLGLOBAL DEBUG ---
+DLGLOBAL DEBUG --- term at _branch0
+DLGLOBAL DEBUG test(_branch0){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(_branch0){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0b){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig0b){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0b){alive}: Removing from parent test(_branch0)
+DLGLOBAL DEBUG 1 (__twig0b.cleanup())
+DLGLOBAL DEBUG test(__twig0b){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig0b){alive}: scene forgets __twig0b
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 2 (__twig0b.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 3 (__twig0b.cleanup(),_branch0.alive(),_branch0.child_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_CHILD_GONE: Dropped reference _branch0.child[1] = __twig0b
+DLGLOBAL DEBUG test(_branch0){alive}: still exists: child[0]
+DLGLOBAL DEBUG 2 (__twig0b.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG 1 (__twig0b.cleanup())
+DLGLOBAL DEBUG test(__twig0b){alive}: cleanup() done
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG test(__twig0b){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig0b){alive}: Deallocated
+DLGLOBAL DEBUG test(__twig0a){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig0a){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig0a){alive}: Removing from parent test(_branch0)
+DLGLOBAL DEBUG 1 (__twig0a.cleanup())
+DLGLOBAL DEBUG test(__twig0a){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig0a){alive}: scene forgets __twig0a
+DLGLOBAL DEBUG test(__twig0a){alive}: removing reference __twig0a.other[0] -> other
+DLGLOBAL DEBUG test(other){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 2 (__twig0a.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 3 (__twig0a.cleanup(),other.alive(),other.other_gone())
+DLGLOBAL DEBUG 2 (__twig0a.cleanup(),other.alive())
+DLGLOBAL DEBUG 1 (__twig0a.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 2 (__twig0a.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 3 (__twig0a.cleanup(),_branch0.alive(),_branch0.child_gone())
+DLGLOBAL DEBUG test(_branch0){alive}: EV_CHILD_GONE: Dropped reference _branch0.child[0] = __twig0a
+DLGLOBAL DEBUG test(_branch0){alive}: No more children
+DLGLOBAL DEBUG 2 (__twig0a.cleanup(),_branch0.alive())
+DLGLOBAL DEBUG test(_branch0){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 1 (__twig0a.cleanup())
+DLGLOBAL DEBUG test(__twig0a){alive}: cleanup() done
+DLGLOBAL DEBUG 0 (-)
+DLGLOBAL DEBUG test(__twig0a){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig0a){alive}: Deallocated
+DLGLOBAL DEBUG test(_branch0){alive}: Removing from parent test(root)
+DLGLOBAL DEBUG 1 (_branch0.cleanup())
+DLGLOBAL DEBUG test(_branch0){alive}: cleanup()
+DLGLOBAL DEBUG test(_branch0){alive}: scene forgets _branch0
+DLGLOBAL DEBUG test(_branch0){alive}: removing reference _branch0.other[0] -> other
+DLGLOBAL DEBUG test(other){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 2 (_branch0.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 3 (_branch0.cleanup(),other.alive(),other.other_gone())
+DLGLOBAL DEBUG test(other){alive}: EV_OTHER_GONE: Dropped reference other.other[0] = _branch0
+DLGLOBAL DEBUG 2 (_branch0.cleanup(),other.alive())
+DLGLOBAL DEBUG test(other){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(other){alive}: pre_term()
+DLGLOBAL DEBUG 3 (_branch0.cleanup(),other.alive(),other.cleanup())
+DLGLOBAL DEBUG test(other){alive}: cleanup()
+DLGLOBAL DEBUG test(other){alive}: scene forgets other
+DLGLOBAL DEBUG test(other){alive}: removing reference other.other[1] -> _branch1
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 4 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),_branch1.other_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_OTHER_GONE: Dropped reference _branch1.other[0] = other
+DLGLOBAL DEBUG 4 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(_branch1){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(_branch1){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1b){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig1b){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1b){alive}: Removing from parent test(_branch1)
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1b.cleanup())
+DLGLOBAL DEBUG test(__twig1b){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig1b){alive}: scene forgets __twig1b
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),2*_branch1.alive(),__twig1b.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 7 (_branch0.cleanup(),other.alive(),other.cleanup(),2*_branch1.alive(),__twig1b.cleanup(),_branch1.child_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_CHILD_GONE: Dropped reference _branch1.child[1] = __twig1b
+DLGLOBAL DEBUG test(_branch1){alive}: still exists: child[0]
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),2*_branch1.alive(),__twig1b.cleanup())
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1b.cleanup())
+DLGLOBAL DEBUG test(__twig1b){alive}: cleanup() done
+DLGLOBAL DEBUG 4 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(__twig1b){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig1b){alive}: Deallocated
+DLGLOBAL DEBUG test(__twig1a){alive}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DLGLOBAL DEBUG test(__twig1a){alive}: pre_term()
+DLGLOBAL DEBUG test(__twig1a){alive}: Removing from parent test(_branch1)
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(__twig1a){alive}: cleanup()
+DLGLOBAL DEBUG test(__twig1a){alive}: scene forgets __twig1a
+DLGLOBAL DEBUG test(__twig1a){alive}: removing reference __twig1a.other[0] -> root
+DLGLOBAL DEBUG test(root){alive}: Received Event EV_OTHER_GONE
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: alive(EV_OTHER_GONE)
+DLGLOBAL DEBUG 7 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup(),root.alive(),root.other_gone())
+DLGLOBAL DEBUG test(root){alive}: EV_OTHER_GONE: Dropped reference root.other[0] = __twig1a
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DLGLOBAL DEBUG test(root){alive}: pre_term()
+DLGLOBAL DEBUG test(_branch1){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL ERROR test(root){alive}: Internal error while terminating child FSMs: a child FSM is stuck
+DLGLOBAL DEBUG 7 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup(),root.alive(),root.cleanup())
+DLGLOBAL DEBUG test(root){alive}: cleanup()
+DLGLOBAL DEBUG test(root){alive}: scene forgets root
+DLGLOBAL DEBUG test(root){alive}: cleanup() done
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup(),root.alive())
+DLGLOBAL DEBUG test(root){alive}: Freeing instance
+DLGLOBAL DEBUG test(root){alive}: Deallocated
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: Received Event EV_CHILD_GONE
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),2*_branch1.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: alive(EV_CHILD_GONE)
+DLGLOBAL DEBUG 7 (_branch0.cleanup(),other.alive(),other.cleanup(),2*_branch1.alive(),__twig1a.cleanup(),_branch1.child_gone())
+DLGLOBAL DEBUG test(_branch1){alive}: EV_CHILD_GONE: Dropped reference _branch1.child[0] = __twig1a
+DLGLOBAL DEBUG test(_branch1){alive}: No more children
+DLGLOBAL DEBUG 6 (_branch0.cleanup(),other.alive(),other.cleanup(),2*_branch1.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(_branch1){alive}: Ignoring trigger to terminate: already terminating
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive(),__twig1a.cleanup())
+DLGLOBAL DEBUG test(__twig1a){alive}: cleanup() done
+DLGLOBAL DEBUG 4 (_branch0.cleanup(),other.alive(),other.cleanup(),_branch1.alive())
+DLGLOBAL DEBUG test(__twig1a){alive}: Freeing instance
+DLGLOBAL DEBUG test(__twig1a){alive}: Deallocated
+DLGLOBAL DEBUG test(_branch1){alive}: Removing from parent test(root)
+DLGLOBAL DEBUG 5 (_branch0.cleanup(),other.alive(),other.cle