core: introduce system state enum

The system state knows the states starting →
running/degraded/maintenance → stopping, where:

starting = system startup
running = normal operation
degraded = at least one unit is currently in failed state
maintenance = rescue/emergency mode is active or queued
stopping = system shutdown

1 files changed, 10 insertions, 0 deletions

diff --git a/src/core/unit.c b/src/core/unit.c
index aa723cb8c5..5c98843549 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -471,6 +471,8 @@ void unit_free(Unit *u) {
                 free(u->cgroup_path);
         }
 
+        set_remove(u->manager->failed_units, u);
+
         free(u->description);
         strv_free(u->documentation);
         free(u->fragment_path);
@@ -1507,6 +1509,7 @@ void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_su
 
         m = u->manager;
 
+        /* Update timestamps for state changes */
         if (m->n_reloading <= 0) {
                 dual_timestamp ts;
 
@@ -1523,6 +1526,13 @@ void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_su
                         u->active_exit_timestamp = ts;
         }
 
+        /* Keep track of failed of units */
+        if (ns == UNIT_FAILED && os != UNIT_FAILED)
+                set_put(u->manager->failed_units, u);
+        else if (os == UNIT_FAILED && ns != UNIT_FAILED)
+                set_remove(u->manager->failed_units, u);
+
+        /* Make sure the cgroup is always removed when we become inactive */
         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
                 unit_destroy_cgroup(u);