unit: introduce OnFailureIsolate=

src/dbus-unit.h

@@ -148,6 +148,7 @@
         { "org.freedesktop.systemd1.Unit", "RefuseManualStop",     bus_property_append_bool,       "b",    &u->meta.refuse_manual_stop       }, \
         { "org.freedesktop.systemd1.Unit", "AllowIsolate",         bus_property_append_bool,       "b",    &u->meta.allow_isolate            }, \
         { "org.freedesktop.systemd1.Unit", "DefaultDependencies",  bus_property_append_bool,       "b",    &u->meta.default_dependencies     }, \
+        { "org.freedesktop.systemd1.Unit", "OnFailureIsolate",     bus_property_append_bool,       "b",    &u->meta.on_failure_isolate       }, \
         { "org.freedesktop.systemd1.Unit", "DefaultControlGroup",  bus_unit_append_default_cgroup, "s",    u                                 }, \
         { "org.freedesktop.systemd1.Unit", "ControlGroup",         bus_unit_append_cgroups,        "as",   u                                 }, \
         { "org.freedesktop.systemd1.Unit", "NeedDaemonReload",     bus_unit_append_need_daemon_reload, "b", u                                }, \

src/job.c

@@ -563,8 +563,14 @@ int job_finish_and_invalidate(Job *j, JobResult result) {
          * the unit itself. We don't tread JOB_CANCELED as failure in
          * this context. And JOB_FAILURE is already handled by the
          * unit itself. */
-        if (result == JOB_TIMEOUT || result == JOB_DEPENDENCY)
+        if (result == JOB_TIMEOUT || result == JOB_DEPENDENCY) {
+                log_notice("Job %s/%s failed with result '%s'.",
+                           u->meta.id,
+                           job_type_to_string(t),
+                           job_result_to_string(result));
+
                 unit_trigger_on_failure(u);
+        }
 
         /* Try to start the next jobs that can be started */
         SET_FOREACH(other, u->meta.dependencies[UNIT_AFTER], i)

src/load-fragment.c

@@ -1851,6 +1851,7 @@ static int load_from_path(Unit *u, const char *path) {
                 { "RefuseManualStop",       config_parse_bool,            0, &u->meta.refuse_manual_stop,                     "Unit"    },
                 { "AllowIsolate",           config_parse_bool,            0, &u->meta.allow_isolate,                          "Unit"    },
                 { "DefaultDependencies",    config_parse_bool,            0, &u->meta.default_dependencies,                   "Unit"    },
+                { "OnFailureIsolate",       config_parse_bool,            0, &u->meta.on_failure_isolate,                     "Unit"    },
                 { "JobTimeoutSec",          config_parse_usec,            0, &u->meta.job_timeout,                            "Unit"    },
                 { "ConditionPathExists",        config_parse_condition_path, CONDITION_PATH_EXISTS, u,                        "Unit"    },
                 { "ConditionPathIsDirectory",   config_parse_condition_path, CONDITION_PATH_IS_DIRECTORY, u,                  "Unit"    },

src/unit.c

@@ -666,11 +666,13 @@ void unit_dump(Unit *u, FILE *f, const char *prefix) {
                         "%s\tStopWhenUnneeded: %s\n"
                         "%s\tRefuseManualStart: %s\n"
                         "%s\tRefuseManualStop: %s\n"
-                        "%s\tDefaultDependencies: %s\n",
+                        "%s\tDefaultDependencies: %s\n"
+                        "%s\rOnFailureIsolate: %s\n",
                         prefix, yes_no(u->meta.stop_when_unneeded),
                         prefix, yes_no(u->meta.refuse_manual_start),
                         prefix, yes_no(u->meta.refuse_manual_stop),
-                        prefix, yes_no(u->meta.default_dependencies));
+                        prefix, yes_no(u->meta.default_dependencies),
+                        prefix, yes_no(u->meta.on_failure_isolate));
 
                 LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
                         fprintf(f, "%s\tControlGroup: %s:%s\n",
@@ -1096,8 +1098,17 @@ void unit_trigger_on_failure(Unit *u) {
 
         assert(u);
 
-        SET_FOREACH(other, u->meta.dependencies[UNIT_ON_FAILURE], i)
-                manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL, NULL);
+        if (set_size(u->meta.dependencies[UNIT_ON_FAILURE]) <= 0)
+                return;
+
+        log_info("Triggering OnFailure= dependencies of %s.", u->meta.id);
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_ON_FAILURE], i) {
+                int r;
+
+                if ((r = manager_add_job(u->meta.manager, JOB_START, other, u->meta.on_failure_isolate ? JOB_ISOLATE : JOB_REPLACE, true, NULL, NULL)) < 0)
+                        log_error("Failed to enqueue OnFailure= job: %s", strerror(-r));
+        }
 }
 
 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_success) {

src/unit.h

@@ -207,6 +207,9 @@ struct Meta {
         /* Allow isolation requests */
         bool allow_isolate;
 
+        /* Isolate OnFailure unit */
+        bool on_failure_isolate;
+
         /* Did the last condition check suceed? */
         bool condition_result;