Refactor dddd45e, schedule work to iterate over services again

Instead of changing the API of service_step(), and relying on all the
different callers to step again, we can schedule another event to do
this for us.

In addition to handling the cond_update() case this also handles all
other callers of service_step().  Ensuring that nested conditions do
trigger changes.

Also, reverting dddd45e fixes a minor regression in service_monitor()
which caused it to not clean up collected bootstrap tasks.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/cond-w.c

@@ -140,23 +140,19 @@ static int svc_has_cond(svc_t *svc)
 static void cond_update(const char *name)
 {
 	svc_t *svc, *iter = NULL;
-	int restart = 0;
 
 	_d("%s", name);
-	do {
-		restart = 0;
-		for (svc = svc_iterator(&iter, 1); svc; svc = svc_iterator(&iter, 0)) {
-			if (!svc_has_cond(svc) || !cond_affects(name, svc->cond))
-				continue;
+	for (svc = svc_iterator(&iter, 1); svc; svc = svc_iterator(&iter, 0)) {
+		if (!svc_has_cond(svc) || !cond_affects(name, svc->cond))
+			continue;
 
-			_d("%s: match <%s> %s(%s)", name ?: "nil", svc->cond, svc->desc, svc->cmd);
-			restart += service_step(svc);
-		}
-	} while (restart);
+		_d("%s: match <%s> %s(%s)", name ?: "nil", svc->cond, svc->desc, svc->cmd);
+		service_step(svc);
+	}
 }
 
 void cond_set(const char *name)
-{	
+{
 	_d("%s", name);
 	if (string_compare(name, "nop"))
 		return;

src/service.c

@@ -48,8 +48,33 @@
 
 #define RESPAWN_MAX    10	/* Prevent endless respawn of faulty services. */
 
+static uev_t wq_timer;
+static int   wq_init = 0;
+
 static void svc_set_state(svc_t *svc, svc_state_t new);
 
+/* Should be generic work, but currently only steps all services */
+static void wq(uev_t *w, void *arg, int events)
+{
+	if (UEV_ERROR == events) {
+		uev_timer_start(w);
+		return;
+	}
+
+	service_step_all(SVC_TYPE_SERVICE | SVC_TYPE_RUNTASK | SVC_TYPE_INETD);
+}
+
+static int schedule_wq(void)
+{
+	if (!wq_init) {
+		wq_init =1;
+		return uev_timer_init(ctx, &wq_timer, wq, NULL, 100, 0);
+	}
+
+	return uev_timer_set(&wq_timer, 100, 0);
+}
+
+
 /**
  * service_timeout_cb - libuev callback wrapper for service timeouts
  * @w:      Watcher
@@ -1012,12 +1037,12 @@ static void svc_set_state(svc_t *svc, svc_state_t new)
  */
 int service_step(svc_t *svc)
 {
-	int err;
-	char *restart_cnt = (char *)&svc->restart_cnt;
-	svc_cmd_t enabled;
-	svc_state_t old_state;
 	cond_state_t cond;
-	int restarts = 0;
+	svc_state_t old_state;
+	svc_cmd_t enabled;
+	char *restart_cnt = (char *)&svc->restart_cnt;
+	int changed = 0;
+	int err;
 
 restart:
 	old_state = svc->state;
@@ -1194,11 +1219,18 @@ restart:
 
 	if (svc->state != old_state) {
 		_d("%20s(%4d): -> %8s", svc->cmd, svc->pid, svc_status(svc));
-		restarts++;
+		changed++;
 		goto restart;
 	}
 
-	return restarts;
+	/*
+	 * When a run/task/service changes state, e.g. transitioning from
+	 * waiting to running, other services may need to change state too.
+	 */
+	if (changed)
+		schedule_wq();
+
+	return 0;
 }
 
 void service_step_all(int types)