+
+char **cg_shorten_controllers(char **controllers) {
+ char **f, **t;
+
+ controllers = strv_uniq(controllers);
+
+ if (!controllers)
+ return controllers;
+
+ for (f = controllers, t = controllers; *f; f++) {
+ int r;
+ const char *p;
+
+ if (streq(*f, "systemd") || streq(*f, SYSTEMD_CGROUP_CONTROLLER)) {
+ free(*f);
+ continue;
+ }
+
+ p = normalize_controller(*f);
+
+ r = check(p);
+ if (r < 0) {
+ log_debug("Controller %s is not available, removing from controllers list.", *f);
+ free(*f);
+ continue;
+ }
+
+ *(t++) = *f;
+ }
+
+ *t = NULL;
+ return controllers;
+}
+
+int cg_pid_get_cgroup(pid_t pid, char **root, char **cgroup) {
+ char *cg_process, *cg_init, *p;
+ int r;
+
+ assert(pid >= 0);
+
+ if (pid == 0)
+ pid = getpid();
+
+ r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &cg_process);
+ if (r < 0)
+ return r;
+
+ r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 1, &cg_init);
+ if (r < 0) {
+ free(cg_process);
+ return r;
+ }
+
+ if (endswith(cg_init, "/system"))
+ cg_init[strlen(cg_init)-7] = 0;
+ else if (streq(cg_init, "/"))
+ cg_init[0] = 0;
+
+ if (startswith(cg_process, cg_init))
+ p = cg_process + strlen(cg_init);
+ else
+ p = cg_process;
+
+ free(cg_init);
+
+ if (cgroup) {
+ char* c;
+
+ c = strdup(p);
+ if (!c) {
+ free(cg_process);
+ return -ENOMEM;
+ }
+
+ *cgroup = c;
+ }
+
+ if (root) {
+ cg_process[p-cg_process] = 0;
+ *root = cg_process;
+ } else
+ free(cg_process);
+
+ return 0;
+}
+
+int cg_pid_get_unit(pid_t pid, char **unit) {
+ int r;
+ char *cgroup, *p, *at, *b;
+ size_t k;
+
+ assert(pid >= 0);
+ assert(unit);
+
+ r = cg_pid_get_cgroup(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ if (!startswith(cgroup, "/system/")) {
+ free(cgroup);
+ return -ENOENT;
+ }
+
+ p = cgroup + 8;
+ k = strcspn(p, "/");
+
+ at = memchr(p, '@', k);
+ if (at && at[1] == '.') {
+ size_t j;
+
+ /* This is a templated service */
+ if (p[k] != '/') {
+ free(cgroup);
+ return -EIO;
+ }
+
+ j = strcspn(p+k+1, "/");
+
+ b = malloc(k + j + 1);
+
+ if (b) {
+ memcpy(b, p, at - p + 1);
+ memcpy(b + (at - p) + 1, p + k + 1, j);
+ memcpy(b + (at - p) + 1 + j, at + 1, k - (at - p) - 1);
+ b[k+j] = 0;
+ }
+ } else
+ b = strndup(p, k);
+
+ free(cgroup);
+
+ if (!b)
+ return -ENOMEM;
+
+ *unit = b;
+ return 0;
+
+}