Protect internal services like dbus-daemon and udevd

In f3669c7 the difference between static and dynamic services was
removed.  This led to a regression in handling internally created
services for, e.g., dbus-daemon and udevd, mentioned in issue #90.

This patch introduces a "protected" flag for svc_t to prevent the
mark-and-sweep handling of regularly loaded services.

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

src/service.c

@@ -732,6 +732,9 @@ recreate:
 	else
 		svc_mark_clean(svc);
 
+	if (!file)
+		svc->protected = 1;
+
 	/* Free duped line, from above */
 	free(line);
 	return 0;

src/svc.c

@@ -356,8 +356,12 @@ void svc_mark_dynamic(void)
 {
 	svc_t *svc, *iter = NULL;
 
-	for (svc = svc_iterator(&iter, 1); svc; svc = svc_iterator(&iter, 0))
+	for (svc = svc_iterator(&iter, 1); svc; svc = svc_iterator(&iter, 0)) {
+		if (svc->protected)
+			continue;
+
 		*((int *)&svc->dirty) = -1;
+	}
 }
 
 void svc_mark_dirty(svc_t *svc)

src/svc.h

@@ -92,6 +92,7 @@ typedef struct svc {
 	pid_t	       pid;
 	const svc_state_t state;       /* Paused, Reloading, Restart, Running, ... */
 	svc_type_t     type;	       /* Service, run, task, inetd, ... */
+	int            protected;      /* Services like dbus-daemon & udev by Finit */
 	const int      dirty;	       /* -1: removal, 0: unmodified, 1: modified */
 	int            starting;       /* ... waiting for pidfile to be re-asserted */
 	int	       runlevels;