Merge pull request #1040 from poettering/cgroup-path-fix

fix "systemctl status idontexist.service" showing the full cgroup tree

2 files changed, 34 insertions, 9 deletions

diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c
index 1892725f91..0a9effda71 100644
--- a/src/core/dbus-unit.c
+++ b/src/core/dbus-unit.c
@@ -697,10 +697,40 @@ static int property_get_cpu_usage(
         return sd_bus_message_append(reply, "t", ns);
 }
 
+static int property_get_cgroup(
+                sd_bus *bus,
+                const char *path,
+                const char *interface,
+                const char *property,
+                sd_bus_message *reply,
+                void *userdata,
+                sd_bus_error *error) {
+
+        Unit *u = userdata;
+        const char *t;
+
+        assert(bus);
+        assert(reply);
+        assert(u);
+
+        /* Three cases: a) u->cgroup_path is NULL, in which case the
+         * unit has no control group, which we report as the empty
+         * string. b) u->cgroup_path is the empty string, which
+         * indicates the root cgroup, which we report as "/". c) all
+         * other cases we report as-is. */
+
+        if (u->cgroup_path)
+                t = isempty(u->cgroup_path) ? "/" : u->cgroup_path;
+        else
+                t = "";
+
+        return sd_bus_message_append(reply, "s", t);
+}
+
 const sd_bus_vtable bus_unit_cgroup_vtable[] = {
         SD_BUS_VTABLE_START(0),
         SD_BUS_PROPERTY("Slice", "s", property_get_slice, 0, 0),
-        SD_BUS_PROPERTY("ControlGroup", "s", NULL, offsetof(Unit, cgroup_path), 0),
+        SD_BUS_PROPERTY("ControlGroup", "s", property_get_cgroup, 0, 0),
         SD_BUS_PROPERTY("MemoryCurrent", "t", property_get_current_memory, 0, 0),
         SD_BUS_PROPERTY("CPUUsageNSec", "t", property_get_cpu_usage, 0, 0),
         SD_BUS_VTABLE_END
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index 587793fb17..3cb5f61868 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -3635,14 +3635,7 @@ static int status_property(const char *name, sd_bus_message *m, UnitStatusInfo *
                 if (r < 0)
                         return bus_log_parse_error(r);
 
-                if (streq(name, "ControlGroup"))
-                        i->control_group = s;
-                else if (!isempty(s)) {
-                        /* For all but the cgroup path (see above) we
-                         * consider the empty string as unset. For the
-                         * cgroup path the empty string refers to the
-                         * root of the cgroup tree. */
-
+                if (!isempty(s)) {
                         if (streq(name, "Id"))
                                 i->id = s;
                         else if (streq(name, "LoadState"))
@@ -3665,6 +3658,8 @@ static int status_property(const char *name, sd_bus_message *m, UnitStatusInfo *
                                         i->control_group = e;
                         }
 #endif
+                        else if (streq(name, "ControlGroup"))
+                                i->control_group = s;
                         else if (streq(name, "StatusText"))
                                 i->status_text = s;
                         else if (streq(name, "PIDFile"))