+ return strv_uniq(controllers);
+}
+
+int cg_pid_get_path_shifted(pid_t pid, char **root, char **cgroup) {
+ _cleanup_free_ char *cg_root = NULL;
+ char *cg_process, *p;
+ int r;
+
+ r = cg_get_root_path(&cg_root);
+ if (r < 0)
+ return r;
+
+ r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cg_process);
+ if (r < 0)
+ return r;
+
+ p = path_startswith(cg_process, cg_root);
+ if (p)
+ p--;
+ else
+ p = cg_process;
+
+ 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_path_decode_unit(const char *cgroup, char **unit){
+ char *e, *c, *s;
+
+ assert(cgroup);
+ assert(unit);
+
+ e = strchrnul(cgroup, '/');
+ c = strndupa(cgroup, e - cgroup);
+ c = cg_unescape(c);
+
+ if (!unit_name_is_valid(c, false))
+ return -EINVAL;
+
+ s = strdup(c);
+ if (!s)
+ return -ENOMEM;
+
+ *unit = s;
+ return 0;
+}
+
+static const char *skip_slices(const char *p) {
+ /* Skips over all slice assignments */
+
+ for (;;) {
+ size_t n;
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (n <= 6 || memcmp(p + n - 6, ".slice", 6) != 0)
+ return p;
+
+ p += n;
+ }
+}
+
+int cg_path_get_unit(const char *path, char **unit) {
+ const char *e;
+
+ assert(path);
+ assert(unit);
+
+ e = skip_slices(path);
+
+ return cg_path_decode_unit(e, unit);
+}
+
+int cg_pid_get_unit(pid_t pid, char **unit) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(unit);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_unit(cgroup, unit);
+}
+
+static const char *skip_session(const char *p) {
+ size_t n;
+
+ assert(p);
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (n <= 12 || memcmp(p, "session-", 8) != 0 || memcmp(p + n - 6, ".scope", 6) != 0)
+ return NULL;
+
+ p += n;
+ p += strspn(p, "/");
+
+ return p;
+}
+
+int cg_path_get_user_unit(const char *path, char **unit) {
+ const char *e;
+
+ assert(path);
+ assert(unit);
+
+ /* We always have to parse the path from the beginning as unit
+ * cgroups might have arbitrary child cgroups and we shouldn't get
+ * confused by those */
+
+ /* Skip slices, if there are any */
+ e = skip_slices(path);
+
+ /* Skip the session scope, require that there is one */
+ e = skip_session(e);
+ if (!e)
+ return -ENOENT;
+
+ /* And skip more slices */
+ e = skip_slices(e);
+
+ return cg_path_decode_unit(e, unit);
+}
+
+int cg_pid_get_user_unit(pid_t pid, char **unit) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(unit);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_user_unit(cgroup, unit);
+}
+
+int cg_path_get_machine_name(const char *path, char **machine) {
+ const char *e, *n, *x;
+ char *s, *r;
+ size_t l;
+
+ assert(path);
+ assert(machine);
+
+ /* Skip slices, if there are any */
+ e = skip_slices(path);
+
+ n = strchrnul(e, '/');
+ if (e == n)
+ return -ENOENT;
+
+ s = strndupa(e, n - e);
+ s = cg_unescape(s);
+
+ x = startswith(s, "machine-");
+ if (!x)
+ return -ENOENT;
+ if (!endswith(x, ".scope"))
+ return -ENOENT;
+
+ l = strlen(x);
+ if (l <= 6)
+ return -ENOENT;
+
+ r = strndup(x, l - 6);
+ if (!r)
+ return -ENOMEM;
+
+ *machine = r;
+ return 0;
+}
+
+int cg_pid_get_machine_name(pid_t pid, char **machine) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(machine);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_machine_name(cgroup, machine);
+}
+
+int cg_path_get_session(const char *path, char **session) {
+ const char *e, *n, *x;
+ char *s, *r;
+ size_t l;
+
+ assert(path);
+ assert(session);
+
+ /* Skip slices, if there are any */
+ e = skip_slices(path);
+
+ n = strchrnul(e, '/');
+ if (e == n)
+ return -ENOENT;
+
+ s = strndupa(e, n - e);
+ s = cg_unescape(s);
+
+ x = startswith(s, "session-");
+ if (!x)
+ return -ENOENT;
+ if (!endswith(x, ".scope"))
+ return -ENOENT;
+
+ l = strlen(x);
+ if (l <= 6)
+ return -ENOENT;
+
+ r = strndup(x, l - 6);
+ if (!r)
+ return -ENOMEM;
+
+ *session = r;
+ return 0;
+}
+
+int cg_pid_get_session(pid_t pid, char **session) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(session);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_session(cgroup, session);
+}
+
+int cg_path_get_owner_uid(const char *path, uid_t *uid) {
+ _cleanup_free_ char *slice = NULL;
+ const char *e;
+ char *s;
+ int r;
+
+ assert(path);
+ assert(uid);
+
+ r = cg_path_get_slice(path, &slice);
+ if (r < 0)
+ return r;
+
+ e = startswith(slice, "user-");
+ if (!e)
+ return -ENOENT;
+ if (!endswith(slice, ".slice"))
+ return -ENOENT;
+
+ s = strndupa(e, strlen(e) - 6);
+ if (!s)
+ return -ENOMEM;
+
+ return parse_uid(s, uid);
+}
+
+int cg_pid_get_owner_uid(pid_t pid, uid_t *uid) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(uid);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_owner_uid(cgroup, uid);
+}
+
+int cg_path_get_slice(const char *p, char **slice) {
+ const char *e = NULL;
+ size_t m = 0;
+
+ assert(p);
+ assert(slice);
+
+ for (;;) {
+ size_t n;
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (n <= 6 || memcmp(p + n - 6, ".slice", 6) != 0) {
+ char *s;
+
+ if (!e)
+ return -ENOENT;
+
+ s = strndup(e, m);
+ if (!s)
+ return -ENOMEM;
+
+ *slice = s;
+ return 0;
+ }
+
+ e = p;
+ m = n;
+
+ p += n;
+ }
+}
+
+int cg_pid_get_slice(pid_t pid, char **slice) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(slice);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_slice(cgroup, slice);
+}
+
+int cg_controller_from_attr(const char *attr, char **controller) {
+ const char *dot;
+ char *c;
+
+ assert(attr);
+ assert(controller);
+
+ if (!filename_is_safe(attr))
+ return -EINVAL;
+
+ dot = strchr(attr, '.');
+ if (!dot) {
+ *controller = NULL;
+ return 0;
+ }
+
+ c = strndup(attr, dot - attr);
+ if (!c)
+ return -ENOMEM;
+
+ if (!cg_controller_is_valid(c, false)) {
+ free(c);
+ return -EINVAL;
+ }
+
+ *controller = c;
+ return 1;
+}
+
+char *cg_escape(const char *p) {
+ bool need_prefix = false;
+
+ /* This implements very minimal escaping for names to be used
+ * as file names in the cgroup tree: any name which might
+ * conflict with a kernel name or is prefixed with '_' is
+ * prefixed with a '_'. That way, when reading cgroup names it
+ * is sufficient to remove a single prefixing underscore if
+ * there is one. */
+
+ /* The return value of this function (unlike cg_unescape())
+ * needs free()! */
+
+ if (p[0] == 0 ||
+ p[0] == '_' ||
+ p[0] == '.' ||
+ streq(p, "notify_on_release") ||
+ streq(p, "release_agent") ||
+ streq(p, "tasks"))
+ need_prefix = true;
+ else {
+ const char *dot;
+
+ dot = strrchr(p, '.');
+ if (dot) {
+
+ if (dot - p == 6 && memcmp(p, "cgroup", 6) == 0)
+ need_prefix = true;
+ else {
+ char *n;
+
+ n = strndupa(p, dot - p);
+
+ if (check_hierarchy(n) >= 0)
+ need_prefix = true;
+ }
+ }
+ }
+
+ if (need_prefix)
+ return strappend("_", p);
+ else
+ return strdup(p);
+}
+
+char *cg_unescape(const char *p) {
+ assert(p);
+
+ /* The return value of this function (unlike cg_escape())
+ * doesn't need free()! */
+
+ if (p[0] == '_')
+ return (char*) p+1;
+
+ return (char*) p;
+}
+
+#define CONTROLLER_VALID \
+ DIGITS LETTERS \
+ "_"
+
+bool cg_controller_is_valid(const char *p, bool allow_named) {
+ const char *t, *s;
+
+ if (!p)
+ return false;
+
+ if (allow_named) {
+ s = startswith(p, "name=");
+ if (s)
+ p = s;
+ }
+
+ if (*p == 0 || *p == '_')
+ return false;
+
+ for (t = p; *t; t++)
+ if (!strchr(CONTROLLER_VALID, *t))
+ return false;
+
+ if (t - p > FILENAME_MAX)
+ return false;
+
+ return true;
+}
+
+int cg_slice_to_path(const char *unit, char **ret) {
+ _cleanup_free_ char *p = NULL, *s = NULL, *e = NULL;
+ const char *dash;
+
+ assert(unit);
+ assert(ret);
+
+ if (!unit_name_is_valid(unit, false))
+ return -EINVAL;
+
+ if (!endswith(unit, ".slice"))
+ return -EINVAL;
+
+ p = unit_name_to_prefix(unit);
+ if (!p)
+ return -ENOMEM;
+
+ dash = strchr(p, '-');
+ while (dash) {
+ _cleanup_free_ char *escaped = NULL;
+ char n[dash - p + sizeof(".slice")];
+
+ strcpy(stpncpy(n, p, dash - p), ".slice");
+
+ if (!unit_name_is_valid(n, false))
+ return -EINVAL;
+
+ escaped = cg_escape(n);
+ if (!escaped)
+ return -ENOMEM;
+
+ if (!strextend(&s, escaped, "/", NULL))
+ return -ENOMEM;
+
+ dash = strchr(dash+1, '-');
+ }
+
+ e = cg_escape(unit);
+ if (!e)
+ return -ENOMEM;
+
+ if (!strextend(&s, e, NULL))
+ return -ENOMEM;
+
+ *ret = s;
+ s = NULL;
+
+ return 0;
+}
+
+int cg_set_attribute(const char *controller, const char *path, const char *attribute, const char *value) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ r = cg_get_path(controller, path, attribute, &p);
+ if (r < 0)
+ return r;
+
+ return write_string_file(p, value);
+}
+
+static const char mask_names[] =
+ "cpu\0"
+ "cpuacct\0"
+ "blkio\0"
+ "memory\0"
+ "devices\0";
+
+int cg_create_everywhere(CGroupControllerMask supported, CGroupControllerMask mask, const char *path) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ /* This one will create a cgroup in our private tree, but also
+ * duplicate it in the trees specified in mask, and remove it
+ * in all others */
+
+ /* First create the cgroup in our own hierarchy. */
+ r = cg_create(SYSTEMD_CGROUP_CONTROLLER, path);
+ if (r < 0)
+ return r;
+
+ /* Then, do the same in the other hierarchies */
+ NULSTR_FOREACH(n, mask_names) {
+ if (mask & bit)
+ cg_create(n, path);
+ else if (supported & bit)
+ cg_trim(n, path, true);
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+int cg_attach_everywhere(CGroupControllerMask supported, const char *path, pid_t pid) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, path, pid);
+ if (r < 0)
+ return r;
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (supported & bit)
+ cg_attach_fallback(n, path, pid);
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+int cg_attach_many_everywhere(CGroupControllerMask supported, const char *path, Set* pids) {
+ Iterator i;
+ void *pidp;
+ int r = 0;
+
+ SET_FOREACH(pidp, pids, i) {
+ pid_t pid = PTR_TO_LONG(pidp);
+ int q;
+
+ q = cg_attach_everywhere(supported, path, pid);
+ if (q < 0)
+ r = q;
+ }
+
+ return r;
+}
+
+int cg_migrate_everywhere(CGroupControllerMask supported, const char *from, const char *to) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ if (!path_equal(from, to)) {
+ r = cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, from, SYSTEMD_CGROUP_CONTROLLER, to, false, true);
+ if (r < 0)
+ return r;
+ }
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (supported & bit)
+ cg_migrate_recursive_fallback(SYSTEMD_CGROUP_CONTROLLER, to, n, to, false, false);
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+int cg_trim_everywhere(CGroupControllerMask supported, const char *path, bool delete_root) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ r = cg_trim(SYSTEMD_CGROUP_CONTROLLER, path, delete_root);
+ if (r < 0)
+ return r;
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (supported & bit)
+ cg_trim(n, path, delete_root);
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+CGroupControllerMask cg_mask_supported(void) {
+ CGroupControllerMask bit = 1, mask = 0;
+ const char *n;
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (check_hierarchy(n) >= 0)
+ mask |= bit;
+
+ bit <<= 1;
+ }
+
+ return mask;