cgroup: when referencing cgroup controller trees allow omission of the path

2 files changed, 24 insertions, 13 deletions

diff --git a/src/cgls/cgls.c b/src/cgls/cgls.c
index c3229ad2d3..c689b5c471 100644
--- a/src/cgls/cgls.c
+++ b/src/cgls/cgls.c
@@ -156,7 +156,9 @@ int main(int argc, char *argv[]) {
 
                 for (i = optind; i < argc; i++) {
                         int q;
-                        printf("%s:\n", argv[i]);
+
+                        fprintf(stdout, "%s:\n", argv[i]);
+                        fflush(stdout);
 
                         if (arg_machine)
                                 root = strjoin("machine/", arg_machine, "/", argv[i], NULL);
diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index dc0fe85ee2..f57f2b2c42 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -1003,19 +1003,28 @@ int cg_split_spec(const char *spec, char **controller, char **path) {
                 return -EINVAL;
         }
 
-        u = strdup(e+1);
-        if (!u) {
-                free(t);
-                return -ENOMEM;
-        }
-        if (!path_is_safe(u) ||
-            !path_is_absolute(u)) {
-                free(t);
-                free(u);
-                return -EINVAL;
-        }
+        if (streq(e+1, "")) {
+                u = strdup("/");
+                if (!u) {
+                        free(t);
+                        return -ENOMEM;
+                }
+        } else {
+                u = strdup(e+1);
+                if (!u) {
+                        free(t);
+                        return -ENOMEM;
+                }
 
-        path_kill_slashes(u);
+                if (!path_is_safe(u) ||
+                    !path_is_absolute(u)) {
+                        free(t);
+                        free(u);
+                        return -EINVAL;
+                }
+
+                path_kill_slashes(u);
+        }
 
         if (controller)
                 *controller = t;