core: log unit failure with type-specific result code

This slightly changes how we log about failures. Previously,
service_enter_dead() would log that a service unit failed along with its
result code, and unit_notify() would do this again but without the
result code. For other unit types only the latter would take effect.

This cleans this up: we keep the message in unit_notify() only for debug
purposes, and add type-specific log lines to all our unit types that can
fail, and always place them before unit_notify() is invoked.

Or in other words: the duplicate log message for service units is
removed, and all other unit types get a more useful line with the
precise result code.

src/core/automount.c

@@ -325,6 +325,9 @@ static void automount_enter_dead(Automount *a, AutomountResult f) {
         if (a->result == AUTOMOUNT_SUCCESS)
                 a->result = f;
 
+        if (a->result != AUTOMOUNT_SUCCESS)
+                log_unit_warning(UNIT(a), "Failed with result '%s'.", automount_result_to_string(a->result));
+
         automount_set_state(a, a->result != AUTOMOUNT_SUCCESS ? AUTOMOUNT_FAILED : AUTOMOUNT_DEAD);
 }
 

src/core/mount.c

@@ -796,6 +796,9 @@ static void mount_enter_dead(Mount *m, MountResult f) {
         if (m->result == MOUNT_SUCCESS)
                 m->result = f;
 
+        if (m->result != MOUNT_SUCCESS)
+                log_unit_warning(UNIT(m), "Failed with result '%s'.", mount_result_to_string(m->result));
+
         mount_set_state(m, m->result != MOUNT_SUCCESS ? MOUNT_FAILED : MOUNT_DEAD);
 
         exec_runtime_destroy(m->exec_runtime);

src/core/path.c

@@ -457,6 +457,9 @@ static void path_enter_dead(Path *p, PathResult f) {
         if (p->result == PATH_SUCCESS)
                 p->result = f;
 
+        if (p->result != PATH_SUCCESS)
+                log_unit_warning(UNIT(p), "Failed with result '%s'.", path_result_to_string(p->result));
+
         path_set_state(p, p->result != PATH_SUCCESS ? PATH_FAILED : PATH_DEAD);
 }
 

src/core/scope.c

@@ -253,6 +253,9 @@ static void scope_enter_dead(Scope *s, ScopeResult f) {
         if (s->result == SCOPE_SUCCESS)
                 s->result = f;
 
+        if (s->result != SCOPE_SUCCESS)
+                log_unit_warning(UNIT(s), "Failed with result '%s'.", scope_result_to_string(s->result));
+
         scope_set_state(s, s->result != SCOPE_SUCCESS ? SCOPE_FAILED : SCOPE_DEAD);
 }
 

src/core/service.c

@@ -1512,12 +1512,13 @@ static void service_enter_dead(Service *s, ServiceResult f, bool allow_restart)
         if (s->result == SERVICE_SUCCESS)
                 s->result = f;
 
+        if (s->result != SERVICE_SUCCESS)
+                log_unit_warning(UNIT(s), "Failed with result '%s'.", service_result_to_string(s->result));
+
         service_set_state(s, s->result != SERVICE_SUCCESS ? SERVICE_FAILED : SERVICE_DEAD);
 
-        if (s->result != SERVICE_SUCCESS) {
-                log_unit_warning(UNIT(s), "Failed with result '%s'.", service_result_to_string(s->result));
+        if (s->result != SERVICE_SUCCESS)
                 emergency_action(UNIT(s)->manager, s->emergency_action, UNIT(s)->reboot_arg, "service failed");
-        }
 
         if (allow_restart && service_shall_restart(s)) {
 

src/core/socket.c

@@ -1983,6 +1983,9 @@ static void socket_enter_dead(Socket *s, SocketResult f) {
         if (s->result == SOCKET_SUCCESS)
                 s->result = f;
 
+        if (s->result != SOCKET_SUCCESS)
+                log_unit_warning(UNIT(s), "Failed with result '%s'.", socket_result_to_string(s->result));
+
         socket_set_state(s, s->result != SOCKET_SUCCESS ? SOCKET_FAILED : SOCKET_DEAD);
 
         exec_runtime_destroy(s->exec_runtime);

src/core/swap.c

@@ -665,6 +665,9 @@ static void swap_enter_dead(Swap *s, SwapResult f) {
         if (s->result == SWAP_SUCCESS)
                 s->result = f;
 
+        if (s->result != SWAP_SUCCESS)
+                log_unit_warning(UNIT(s), "Failed with result '%s'.", swap_result_to_string(s->result));
+
         swap_set_state(s, s->result != SWAP_SUCCESS ? SWAP_FAILED : SWAP_DEAD);
 
         exec_runtime_destroy(s->exec_runtime);

src/core/timer.c

@@ -296,6 +296,9 @@ static void timer_enter_dead(Timer *t, TimerResult f) {
         if (t->result == TIMER_SUCCESS)
                 t->result = f;
 
+        if (t->result != TIMER_SUCCESS)
+                log_unit_warning(UNIT(t), "Failed with result '%s'.", timer_result_to_string(t->result));
+
         timer_set_state(t, t->result != TIMER_SUCCESS ? TIMER_FAILED : TIMER_DEAD);
 }
 

src/core/unit.c

@@ -2272,7 +2272,7 @@ void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_su
                         check_unneeded_dependencies(u);
 
                 if (ns != os && ns == UNIT_FAILED) {
-                        log_unit_notice(u, "Unit entered failed state.");
+                        log_unit_debug(u, "Unit entered failed state.");
                         unit_start_on_failure(u);
                 }
         }