core: rework unit name validation and manipulation logic

A variety of changes:

- Make sure all our calls distuingish OOM from other errors if OOM is
  not the only error possible.

- Be much stricter when parsing escaped paths, do not accept trailing or
  leading escaped slashes.

- Change unit validation to take a bit mask for allowing plain names,
  instance names or template names or an combination thereof.

- Refuse manipulating invalid unit name

34 files changed, 1033 insertions, 834 deletions

diff --git a/src/core/automount.c b/src/core/automount.c
index 73b75f163e..1806fa39d3 100644
--- a/src/core/automount.c
+++ b/src/core/automount.c
@@ -167,8 +167,9 @@ static int automount_add_default_dependencies(Automount *a) {
 }
 
 static int automount_verify(Automount *a) {
-        bool b;
         _cleanup_free_ char *e = NULL;
+        int r;
+
         assert(a);
 
         if (UNIT(a)->load_state != UNIT_LOADED)
@@ -179,13 +180,11 @@ static int automount_verify(Automount *a) {
                 return -EINVAL;
         }
 
-        e = unit_name_from_path(a->where, ".automount");
-        if (!e)
-                return -ENOMEM;
-
-        b = unit_has_name(UNIT(a), e);
+        r = unit_name_from_path(a->where, ".automount", &e);
+        if (r < 0)
+                return log_unit_error(UNIT(a)->id, "Failed to generate unit name from path: %m");
 
-        if (!b) {
+        if (!unit_has_name(UNIT(a), e)) {
                 log_unit_error(UNIT(a)->id, "%s's Where setting doesn't match unit name. Refusing.", UNIT(a)->id);
                 return -EINVAL;
         }
@@ -209,9 +208,9 @@ static int automount_load(Unit *u) {
                 Unit *x;
 
                 if (!a->where) {
-                        a->where = unit_name_to_path(u->id);
-                        if (!a->where)
-                                return -ENOMEM;
+                        r = unit_name_to_path(u->id, &a->where);
+                        if (r < 0)
+                                return r;
                 }
 
                 path_kill_slashes(a->where);
diff --git a/src/core/busname.c b/src/core/busname.c
index 20d49fe3e9..8e92fb47fe 100644
--- a/src/core/busname.c
+++ b/src/core/busname.c
@@ -163,9 +163,9 @@ static int busname_add_extras(BusName *n) {
         assert(n);
 
         if (!n->name) {
-                n->name = unit_name_to_prefix(u->id);
-                if (!n->name)
-                        return -ENOMEM;
+                r = unit_name_to_prefix(u->id, &n->name);
+                if (r < 0)
+                        return r;
         }
 
         if (!u->description) {
diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c
index 2699e81492..056c7117b2 100644
--- a/src/core/dbus-unit.c
+++ b/src/core/dbus-unit.c
@@ -940,7 +940,7 @@ static int bus_unit_set_transient_property(
                 if (r < 0)
                         return r;
 
-                if (!unit_name_is_valid(s, TEMPLATE_INVALID) || !endswith(s, ".slice"))
+                if (!unit_name_is_valid(s, UNIT_NAME_PLAIN) || !endswith(s, ".slice"))
                         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid slice name %s", s);
 
                 if (isempty(s)) {
@@ -988,7 +988,7 @@ static int bus_unit_set_transient_property(
                         return r;
 
                 while ((r = sd_bus_message_read(message, "s", &other)) > 0) {
-                        if (!unit_name_is_valid(other, TEMPLATE_INVALID))
+                        if (!unit_name_is_valid(other, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))
                                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid unit name %s", other);
 
                         if (mode != UNIT_CHECK) {
diff --git a/src/core/device.c b/src/core/device.c
index f8e65b876f..2c56c5a2d2 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -279,9 +279,9 @@ static int device_add_udev_wants(Unit *u, struct udev_device *dev) {
                 memcpy(e, word, l);
                 e[l] = 0;
 
-                n = unit_name_mangle(e, MANGLE_NOGLOB);
-                if (!n)
-                        return log_oom();
+                r = unit_name_mangle(e, UNIT_NAME_NOGLOB, &n);
+                if (r < 0)
+                        return log_unit_error_errno(u->id, r, "Failed to mangle unit name: %m");
 
                 r = unit_add_dependency_by_name(u, UNIT_WANTS, n, NULL, true);
                 if (r < 0)
@@ -308,9 +308,9 @@ static int device_setup_unit(Manager *m, struct udev_device *dev, const char *pa
         if (!sysfs)
                 return 0;
 
-        e = unit_name_from_path(path, ".device");
-        if (!e)
-                return log_oom();
+        r = unit_name_from_path(path, ".device", &e);
+        if (r < 0)
+                return log_unit_error_errno(u->id, r, "Failed to generate device name: %m");
 
         u = manager_get_unit(m, e);
 
@@ -491,6 +491,7 @@ static int device_update_found_by_sysfs(Manager *m, const char *sysfs, bool add,
 static int device_update_found_by_name(Manager *m, const char *path, bool add, DeviceFound found, bool now) {
         _cleanup_free_ char *e = NULL;
         Unit *u;
+        int r;
 
         assert(m);
         assert(path);
@@ -498,9 +499,9 @@ static int device_update_found_by_name(Manager *m, const char *path, bool add, D
         if (found == DEVICE_NOT_FOUND)
                 return 0;
 
-        e = unit_name_from_path(path, ".device");
-        if (!e)
-                return log_oom();
+        r = unit_name_from_path(path, ".device", &e);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name from device path: %m");
 
         u = manager_get_unit(m, e);
         if (!u)
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index b76656b931..970120ab70 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -3394,7 +3394,7 @@ static int open_follow(char **filename, FILE **_f, Set *names, char **_final) {
                  * unit name. */
                 name = basename(*filename);
 
-                if (unit_name_is_valid(name, TEMPLATE_VALID)) {
+                if (unit_name_is_valid(name, UNIT_NAME_ANY)) {
 
                         id = set_get(names, name);
                         if (!id) {
@@ -3642,11 +3642,11 @@ int unit_load_fragment(Unit *u) {
 
         /* Look for a template */
         if (u->load_state == UNIT_STUB && u->instance) {
-                _cleanup_free_ char *k;
+                _cleanup_free_ char *k = NULL;
 
-                k = unit_name_template(u->id);
-                if (!k)
-                        return -ENOMEM;
+                r = unit_name_template(u->id, &k);
+                if (r < 0)
+                        return r;
 
                 r = load_from_path(u, k);
                 if (r < 0)
@@ -3659,9 +3659,9 @@ int unit_load_fragment(Unit *u) {
                                 if (t == u->id)
                                         continue;
 
-                                z = unit_name_template(t);
-                                if (!z)
-                                        return -ENOMEM;
+                                r = unit_name_template(t, &z);
+                                if (r < 0)
+                                        return r;
 
                                 r = load_from_path(u, z);
                                 if (r < 0)
diff --git a/src/core/manager.c b/src/core/manager.c
index b49452151b..8c8645b68d 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -1306,7 +1306,7 @@ int manager_load_unit_prepare(
 
         t = unit_name_to_type(name);
 
-        if (t == _UNIT_TYPE_INVALID || !unit_name_is_valid(name, TEMPLATE_INVALID))
+        if (t == _UNIT_TYPE_INVALID || !unit_name_is_valid(name, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))
                 return sd_bus_error_setf(e, SD_BUS_ERROR_INVALID_ARGS, "Unit name %s is not valid.", name);
 
         ret = manager_get_unit(m, name);
@@ -2093,7 +2093,7 @@ void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) {
 #ifdef HAVE_AUDIT
         _cleanup_free_ char *p = NULL;
         const char *msg;
-        int audit_fd;
+        int audit_fd, r;
 
         audit_fd = get_audit_fd();
         if (audit_fd < 0)
@@ -2110,9 +2110,9 @@ void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) {
         if (u->type != UNIT_SERVICE)
                 return;
 
-        p = unit_name_to_prefix_and_instance(u->id);
-        if (!p) {
-                log_oom();
+        r = unit_name_to_prefix_and_instance(u->id, &p);
+        if (r < 0) {
+                log_error_errno(r, "Failed to extract prefix and instance of unit name: %m");
                 return;
         }
 
@@ -3027,15 +3027,16 @@ void manager_status_printf(Manager *m, StatusType type, const char *status, cons
 int manager_get_unit_by_path(Manager *m, const char *path, const char *suffix, Unit **_found) {
         _cleanup_free_ char *p = NULL;
         Unit *found;
+        int r;
 
         assert(m);
         assert(path);
         assert(suffix);
         assert(_found);
 
-        p = unit_name_from_path(path, suffix);
-        if (!p)
-                return -ENOMEM;
+        r = unit_name_from_path(path, suffix, &p);
+        if (r < 0)
+                return r;
 
         found = manager_get_unit(m, p);
         if (!found) {
diff --git a/src/core/mount.c b/src/core/mount.c
index d0c41a73a9..65a66b468f 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -435,7 +435,7 @@ static int mount_add_default_dependencies(Mount *m) {
 
 static int mount_verify(Mount *m) {
         _cleanup_free_ char *e = NULL;
-        bool b;
+        int r;
 
         assert(m);
 
@@ -445,12 +445,11 @@ static int mount_verify(Mount *m) {
         if (!m->from_fragment && !m->from_proc_self_mountinfo)
                 return -ENOENT;
 
-        e = unit_name_from_path(m->where, ".mount");
-        if (!e)
-                return -ENOMEM;
+        r = unit_name_from_path(m->where, ".mount", &e);
+        if (r < 0)
+                return log_unit_error_errno(UNIT(m)->id, r, "Failed to generate unit name from mount path: %m");
 
-        b = unit_has_name(UNIT(m), e);
-        if (!b) {
+        if (!unit_has_name(UNIT(m), e)) {
                 log_unit_error(UNIT(m)->id, "%s's Where= setting doesn't match unit name. Refusing.", UNIT(m)->id);
                 return -EINVAL;
         }
@@ -483,9 +482,9 @@ static int mount_add_extras(Mount *m) {
                 m->from_fragment = true;
 
         if (!m->where) {
-                m->where = unit_name_to_path(u->id);
-                if (!m->where)
-                        return -ENOMEM;
+                r = unit_name_to_path(u->id, &m->where);
+                if (r < 0)
+                        return r;
         }
 
         path_kill_slashes(m->where);
@@ -1419,9 +1418,9 @@ static int mount_setup_unit(
         if (!is_path(where))
                 return 0;
 
-        e = unit_name_from_path(where, ".mount");
-        if (!e)
-                return -ENOMEM;
+        r = unit_name_from_path(where, ".mount", &e);
+        if (r < 0)
+                return r;
 
         u = manager_get_unit(m, e);
         if (!u) {
diff --git a/src/core/snapshot.c b/src/core/snapshot.c
index b70c3beb60..2c00680f16 100644
--- a/src/core/snapshot.c
+++ b/src/core/snapshot.c
@@ -201,10 +201,10 @@ int snapshot_create(Manager *m, const char *name, bool cleanup, sd_bus_error *e,
         assert(_s);
 
         if (name) {
-                if (!unit_name_is_valid(name, TEMPLATE_INVALID))
+                if (!unit_name_is_valid(name, UNIT_NAME_PLAIN))
                         return sd_bus_error_setf(e, SD_BUS_ERROR_INVALID_ARGS, "Unit name %s is not valid.", name);
 
-                if (unit_name_to_type(name) != UNIT_SNAPSHOT)
+                if (!endswith(name, ".snapshot"))
                         return sd_bus_error_setf(e, SD_BUS_ERROR_INVALID_ARGS, "Unit name %s lacks snapshot suffix.", name);
 
                 if (manager_get_unit(m, name))
diff --git a/src/core/socket.c b/src/core/socket.c
index 67beda44d6..55334e4a54 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -196,12 +196,15 @@ int socket_instantiate_service(Socket *s) {
          * here. For Accept=no this is mostly a NOP since the service
          * is figured out at load time anyway. */
 
-        if (UNIT_DEREF(s->service) || !s->accept)
+        if (UNIT_DEREF(s->service))
                 return 0;
 
-        prefix = unit_name_to_prefix(UNIT(s)->id);
-        if (!prefix)
-                return -ENOMEM;
+        if (!s->accept)
+                return 0;
+
+        r = unit_name_to_prefix(UNIT(s)->id, &prefix);
+        if (r < 0)
+                return r;
 
         if (asprintf(&name, "%s@%u.service", prefix, s->n_accepted) < 0)
                 return -ENOMEM;
@@ -1836,17 +1839,13 @@ static void socket_enter_running(Socket *s, int cfd) {
                         return;
                 }
 
-                prefix = unit_name_to_prefix(UNIT(s)->id);
-                if (!prefix) {
-                        r = -ENOMEM;
+                r = unit_name_to_prefix(UNIT(s)->id, &prefix);
+                if (r < 0)
                         goto fail;
-                }
 
-                name = unit_name_build(prefix, instance, ".service");
-                if (!name) {
-                        r = -ENOMEM;
+                r = unit_name_build(prefix, instance, ".service", &name);
+                if (r < 0)
                         goto fail;
-                }
 
                 r = unit_add_name(UNIT_DEREF(s->service), name);
                 if (r < 0)
diff --git a/src/core/swap.c b/src/core/swap.c
index a9834a7fe5..3327cd958f 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -222,18 +222,17 @@ static int swap_add_default_dependencies(Swap *s) {
 }
 
 static int swap_verify(Swap *s) {
-        bool b;
         _cleanup_free_ char *e = NULL;
+        int r;
 
         if (UNIT(s)->load_state != UNIT_LOADED)
                 return 0;
 
-        e = unit_name_from_path(s->what, ".swap");
-        if (!e)
-                return log_oom();
+        r = unit_name_from_path(s->what, ".swap", &e);
+        if (r < 0)
+                return log_unit_error_errno(UNIT(s)->id, r, "%s: failed to generate unit name from path: %m", UNIT(s)->id);
 
-        b = unit_has_name(UNIT(s), e);
-        if (!b) {
+        if (!unit_has_name(UNIT(s), e)) {
                 log_unit_error(UNIT(s)->id, "%s: Value of \"What\" and unit name do not match, not loading.", UNIT(s)->id);
                 return -EINVAL;
         }
@@ -289,8 +288,11 @@ static int swap_load(Unit *u) {
                                 s->what = strdup(s->parameters_fragment.what);
                         else if (s->parameters_proc_swaps.what)
                                 s->what = strdup(s->parameters_proc_swaps.what);
-                        else
-                                s->what = unit_name_to_path(u->id);
+                        else {
+                                r = unit_name_to_path(u->id, &s->what);
+                                if (r < 0)
+                                        return r;
+                        }
 
                         if (!s->what)
                                 return -ENOMEM;
@@ -355,9 +357,9 @@ static int swap_setup_unit(
         assert(what);
         assert(what_proc_swaps);
 
-        e = unit_name_from_path(what, ".swap");
-        if (!e)
-                return log_oom();
+        r = unit_name_from_path(what, ".swap", &e);
+        if (r < 0)
+                return log_unit_error_errno(u->id, r, "Failed to generate unit name from path: %m");
 
         u = manager_get_unit(m, e);
 
@@ -1329,9 +1331,9 @@ int swap_process_device_new(Manager *m, struct udev_device *dev) {
         if (!dn)
                 return 0;
 
-        e = unit_name_from_path(dn, ".swap");
-        if (!e)
-                return -ENOMEM;
+        r = unit_name_from_path(dn, ".swap", &e);
+        if (r < 0)
+                return r;
 
         s = hashmap_get(m->units, e);
         if (s)
@@ -1340,15 +1342,14 @@ int swap_process_device_new(Manager *m, struct udev_device *dev) {
         first = udev_device_get_devlinks_list_entry(dev);
         udev_list_entry_foreach(item, first) {
                 _cleanup_free_ char *n = NULL;
+                int q;
 
-                n = unit_name_from_path(udev_list_entry_get_name(item), ".swap");
-                if (!n)
-                        return -ENOMEM;
+                q = unit_name_from_path(udev_list_entry_get_name(item), ".swap", &n);
+                if (q < 0)
+                        return q;
 
                 s = hashmap_get(m->units, n);
                 if (s) {
-                        int q;
-
                         q = swap_set_devnode(s, dn);
                         if (q < 0)
                                 r = q;
diff --git a/src/core/unit-printf.c b/src/core/unit-printf.c
index 5513fe7d9c..8050e2fd66 100644
--- a/src/core/unit-printf.c
+++ b/src/core/unit-printf.c
@@ -30,83 +30,54 @@
 
 static int specifier_prefix_and_instance(char specifier, void *data, void *userdata, char **ret) {
         Unit *u = userdata;
-        char *n;
 
         assert(u);
 
-        n = unit_name_to_prefix_and_instance(u->id);
-        if (!n)
-                return -ENOMEM;
-
-        *ret = n;
-        return 0;
+        return unit_name_to_prefix_and_instance(u->id, ret);
 }
 
 static int specifier_prefix(char specifier, void *data, void *userdata, char **ret) {
         Unit *u = userdata;
-        char *n;
 
         assert(u);
 
-        n = unit_name_to_prefix(u->id);
-        if (!n)
-                return -ENOMEM;
-
-        *ret = n;
-        return 0;
+        return unit_name_to_prefix(u->id, ret);
 }
 
 static int specifier_prefix_unescaped(char specifier, void *data, void *userdata, char **ret) {
-        Unit *u = userdata;
         _cleanup_free_ char *p = NULL;
-        char *n;
+        Unit *u = userdata;
+        int r;
 
         assert(u);
 
-        p = unit_name_to_prefix(u->id);
-        if (!p)
-                return -ENOMEM;
-
-        n = unit_name_unescape(p);
-        if (!n)
-                return -ENOMEM;
+        r = unit_name_to_prefix(u->id, &p);
+        if (r < 0)
+                return r;
 
-        *ret = n;
-        return 0;
+        return unit_name_unescape(p, ret);
 }
 
 static int specifier_instance_unescaped(char specifier, void *data, void *userdata, char **ret) {
         Unit *u = userdata;
-        char *n;
 
         assert(u);
 
         if (!u->instance)
-                return -EOPNOTSUPP;
-
-        n = unit_name_unescape(u->instance);
-        if (!n)
-                return -ENOMEM;
+                return -EINVAL;
 
-        *ret = n;
-        return 0;
+        return unit_name_unescape(u->instance, ret);
 }
 
 static int specifier_filename(char specifier, void *data, void *userdata, char **ret) {
         Unit *u = userdata;
-        char *n;
 
         assert(u);
 
         if (u->instance)
-                n = unit_name_path_unescape(u->instance);
+                return unit_name_path_unescape(u->instance, ret);
         else
-                n = unit_name_to_path(u->id);
-        if (!n)
-                return -ENOMEM;
-
-        *ret = n;
-        return 0;
+                return unit_name_to_path(u->id, ret);
 }
 
 static int specifier_cgroup(char specifier, void *data, void *userdata, char **ret) {
@@ -195,7 +166,7 @@ static int specifier_user_name(char specifier, void *data, void *userdata, char
 
         c = unit_get_exec_context(u);
         if (!c)
-                return -EOPNOTSUPP;
+                return -EINVAL;
 
         if (u->manager->running_as == SYSTEMD_SYSTEM) {
 
diff --git a/src/core/unit.c b/src/core/unit.c
index 6071bd51b1..6513bcb1cb 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -143,21 +143,31 @@ int unit_add_name(Unit *u, const char *text) {
         assert(u);
         assert(text);
 
-        if (unit_name_is_template(text)) {
+        if (unit_name_is_valid(text, UNIT_NAME_TEMPLATE)) {
 
                 if (!u->instance)
                         return -EINVAL;
 
-                s = unit_name_replace_instance(text, u->instance);
-        } else
+                r = unit_name_replace_instance(text, u->instance, &s);
+                if (r < 0)
+                        return r;
+        } else {
                 s = strdup(text);
-        if (!s)
-                return -ENOMEM;
+                if (!s)
+                        return -ENOMEM;
+        }
 
-        if (!unit_name_is_valid(s, TEMPLATE_INVALID))
+        if (set_contains(u->names, s))
+                return 0;
+        if (hashmap_contains(u->manager->units, s))
+                return -EEXIST;
+
+        if (!unit_name_is_valid(s, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))
                 return -EINVAL;
 
-        assert_se((t = unit_name_to_type(s)) >= 0);
+        t = unit_name_to_type(s);
+        if (t < 0)
+                return -EINVAL;
 
         if (u->type != _UNIT_TYPE_INVALID && t != u->type)
                 return -EINVAL;
@@ -170,25 +180,25 @@ int unit_add_name(Unit *u, const char *text) {
                 return -EINVAL;
 
         /* Ensure that this unit is either instanced or not instanced,
-         * but not both. */
+         * but not both. Note that we do allow names with different
+         * instance names however! */
         if (u->type != _UNIT_TYPE_INVALID && !u->instance != !i)
                 return -EINVAL;
 
-        if (unit_vtable[t]->no_alias &&
-            !set_isempty(u->names) &&
-            !set_get(u->names, s))
+        if (unit_vtable[t]->no_alias && !set_isempty(u->names))
                 return -EEXIST;
 
         if (hashmap_size(u->manager->units) >= MANAGER_MAX_NAMES)
                 return -E2BIG;
 
         r = set_put(u->names, s);
-        if (r <= 0)
+        if (r < 0)
                 return r;
+        assert(r > 0);
 
         r = hashmap_put(u->manager->units, s, u);
         if (r < 0) {
-                set_remove(u->names, s);
+                (void) set_remove(u->names, s);
                 return r;
         }
 
@@ -218,14 +228,14 @@ int unit_choose_id(Unit *u, const char *name) {
         assert(u);
         assert(name);
 
-        if (unit_name_is_template(name)) {
+        if (unit_name_is_valid(name, UNIT_NAME_TEMPLATE)) {
 
                 if (!u->instance)
                         return -EINVAL;
 
-                t = unit_name_replace_instance(name, u->instance);
-                if (!t)
-                        return -ENOMEM;
+                r = unit_name_replace_instance(name, u->instance, &t);
+                if (r < 0)
+                        return r;
 
                 name = t;
         }
@@ -235,6 +245,7 @@ int unit_choose_id(Unit *u, const char *name) {
         if (!s)
                 return -ENOENT;
 
+        /* Determine the new instance from the new id */
         r = unit_name_to_instance(s, &i);
         if (r < 0)
                 return r;
@@ -748,24 +759,22 @@ int unit_merge_by_name(Unit *u, const char *name) {
         assert(u);
         assert(name);
 
-        if (unit_name_is_template(name)) {
+        if (unit_name_is_valid(name, UNIT_NAME_TEMPLATE)) {
                 if (!u->instance)
                         return -EINVAL;
 
-                s = unit_name_replace_instance(name, u->instance);
-                if (!s)
-                        return -ENOMEM;
+                r = unit_name_replace_instance(name, u->instance, &s);
+                if (r < 0)
+                        return r;
 
                 name = s;
         }
 
         other = manager_get_unit(u->manager, name);
-        if (!other)
-                r = unit_add_name(u, name);
-        else
-                r = unit_merge(u, other);
+        if (other)
+                return unit_merge(u, other);
 
-        return r;
+        return unit_add_name(u, name);
 }
 
 Unit* unit_follow_merge(Unit *u) {
@@ -2294,58 +2303,55 @@ int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit
         if (r < 0)
                 return r;
 
-        r = unit_add_dependency(u, e, other, add_reference);
-        if (r < 0)
-                return r;
-
-        return 0;
+        return unit_add_dependency(u, e, other, add_reference);
 }
 
-static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
-        char *s;
+static int resolve_template(Unit *u, const char *name, const char*path, char **buf, const char **ret) {
+        int r;
 
         assert(u);
         assert(name || path);
-        assert(p);
+        assert(buf);
+        assert(ret);
 
         if (!name)
                 name = basename(path);
 
-        if (!unit_name_is_template(name)) {
-                *p = NULL;
-                return name;
+        if (!unit_name_is_valid(name, UNIT_NAME_TEMPLATE)) {
+                *buf = NULL;
+                *ret = name;
+                return 0;
         }
 
         if (u->instance)
-                s = unit_name_replace_instance(name, u->instance);
+                r = unit_name_replace_instance(name, u->instance, buf);
         else {
                 _cleanup_free_ char *i = NULL;
 
-                i = unit_name_to_prefix(u->id);
-                if (!i)
-                        return NULL;
+                r = unit_name_to_prefix(u->id, &i);
+                if (r < 0)
+                        return r;
 
-                s = unit_name_replace_instance(name, i);
+                r = unit_name_replace_instance(name, i, buf);
         }
+        if (r < 0)
+                return r;
 
-        if (!s)
-                return NULL;
-
-        *p = s;
-        return s;
+        *ret = *buf;
+        return 0;
 }
 
 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
+        _cleanup_free_ char *buf = NULL;
         Unit *other;
         int r;
-        _cleanup_free_ char *s = NULL;
 
         assert(u);
         assert(name || path);
 
-        name = resolve_template(u, name, path, &s);
-        if (!name)
-                return -ENOMEM;
+        r = resolve_template(u, name, path, &buf, &name);
+        if (r < 0)
+                return r;
 
         r = manager_load_unit(u->manager, name, path, NULL, &other);
         if (r < 0)
@@ -2355,16 +2361,16 @@ int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, con
 }
 
 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
-        _cleanup_free_ char *s = NULL;
+        _cleanup_free_ char *buf = NULL;
         Unit *other;
         int r;
 
         assert(u);
         assert(name || path);
 
-        name = resolve_template(u, name, path, &s);
-        if (!name)
-                return -ENOMEM;
+        r = resolve_template(u, name, path, &buf, &name);
+        if (r < 0)
+                return r;
 
         r = manager_load_unit(u->manager, name, path, NULL, &other);
         if (r < 0)
@@ -2374,16 +2380,16 @@ int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency
 }
 
 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
+        _cleanup_free_ char *buf = NULL;
         Unit *other;
         int r;
-        _cleanup_free_ char *s = NULL;
 
         assert(u);
         assert(name || path);
 
-        name = resolve_template(u, name, path, &s);
-        if (!name)
-                return -ENOMEM;
+        r = resolve_template(u, name, path, &buf, &name);
+        if (r < 0)
+                return r;
 
         r = manager_load_unit(u->manager, name, path, NULL, &other);
         if (r < 0)
@@ -2393,26 +2399,22 @@ int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *n
 }
 
 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference) {
+        _cleanup_free_ char *buf = NULL;
         Unit *other;
         int r;
-        _cleanup_free_ char *s = NULL;
 
         assert(u);
         assert(name || path);
 
-        name = resolve_template(u, name, path, &s);
-        if (!name)
-                return -ENOMEM;
-
-        r = manager_load_unit(u->manager, name, path, NULL, &other);
+        r  = resolve_template(u, name, path, &buf, &name);
         if (r < 0)
                 return r;
 
-        r = unit_add_two_dependencies(other, d, e, u, add_reference);
+        r = manager_load_unit(u->manager, name, path, NULL, &other);
         if (r < 0)
                 return r;
 
-        return r;
+        return unit_add_two_dependencies(other, d, e, u, add_reference);
 }
 
 int set_unit_path(const char *p) {
@@ -2475,14 +2477,14 @@ int unit_add_default_slice(Unit *u, CGroupContext *c) {
                 /* Implicitly place all instantiated units in their
                  * own per-template slice */
 
-                prefix = unit_name_to_prefix(u->id);
-                if (!prefix)
-                        return -ENOMEM;
+                r = unit_name_to_prefix(u->id, &prefix);
+                if (r < 0)
+                        return r;
 
                 /* The prefix is already escaped, but it might include
                  * "-" which has a special meaning for slice units,
                  * hence escape it here extra. */
-                escaped = strreplace(prefix, "-", "\\x2d");
+                escaped = unit_name_escape(prefix);
                 if (!escaped)
                         return -ENOMEM;
 
@@ -2525,11 +2527,11 @@ int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
         assert(type);
         assert(_found);
 
-        t = unit_name_change_suffix(u->id, type);
-        if (!t)
-                return -ENOMEM;
-
-        assert(!unit_has_name(u, t));
+        r = unit_name_change_suffix(u->id, type, &t);
+        if (r < 0)
+                return r;
+        if (unit_has_name(u, t))
+                return -EINVAL;
 
         r = manager_load_unit(u->manager, t, NULL, NULL, _found);
         assert(r < 0 || *_found != u);
@@ -2858,9 +2860,9 @@ int unit_add_node_link(Unit *u, const char *what, bool wants) {
         if (!unit_type_supported(UNIT_DEVICE))
                 return 0;
 
-        e = unit_name_from_path(what, ".device");
-        if (!e)
-                return -ENOMEM;
+        r = unit_name_from_path(what, ".device", &e);
+        if (r < 0)
+                return r;
 
         r = manager_load_unit(u->manager, e, NULL, NULL, &device);
         if (r < 0)
diff --git a/src/cryptsetup/cryptsetup-generator.c b/src/cryptsetup/cryptsetup-generator.c
index 5d234e6a5a..755ee5d88d 100644
--- a/src/cryptsetup/cryptsetup-generator.c
+++ b/src/cryptsetup/cryptsetup-generator.c
@@ -78,9 +78,9 @@ static int create_disk(
         if (!e)
                 return log_oom();
 
-        n = unit_name_build("systemd-cryptsetup", e, ".service");
-        if (!n)
-                return log_oom();
+        r = unit_name_build("systemd-cryptsetup", e, ".service", &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         p = strjoin(arg_dest, "/", n, NULL);
         if (!p)
@@ -90,9 +90,9 @@ static int create_disk(
         if (!u)
                 return log_oom();
 
-        d = unit_name_from_path(u, ".device");
-        if (!d)
-                return log_oom();
+        r = unit_name_from_path(u, ".device", &d);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         f = fopen(p, "wxe");
         if (!f)
@@ -128,11 +128,11 @@ static int create_disk(
                         if (!path_equal(uu, "/dev/null")) {
 
                                 if (is_device_path(uu)) {
-                                        _cleanup_free_ char *dd;
+                                        _cleanup_free_ char *dd = NULL;
 
-                                        dd = unit_name_from_path(uu, ".device");
-                                        if (!dd)
-                                                return log_oom();
+                                        r = unit_name_from_path(uu, ".device", &dd);
+                                        if (r < 0)
+                                                return log_error_errno(r, "Failed to generate unit name: %m");
 
                                         fprintf(f, "After=%1$s\nRequires=%1$s\n", dd);
                                 } else
diff --git a/src/dbus1-generator/dbus1-generator.c b/src/dbus1-generator/dbus1-generator.c
index 2e08af2df2..c909a4b1da 100644
--- a/src/dbus1-generator/dbus1-generator.c
+++ b/src/dbus1-generator/dbus1-generator.c
@@ -188,7 +188,7 @@ static int add_dbus(const char *path, const char *fname, const char *type) {
         }
 
         if (service) {
-                if (!unit_name_is_valid(service, TEMPLATE_INVALID)) {
+                if (!unit_name_is_valid(service, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE)) {
                         log_warning("Unit name %s is not valid, ignoring.", service);
                         return 0;
                 }
diff --git a/src/debug-generator/debug-generator.c b/src/debug-generator/debug-generator.c
index 1b9019325c..9d0ab06e2f 100644
--- a/src/debug-generator/debug-generator.c
+++ b/src/debug-generator/debug-generator.c
@@ -41,9 +41,9 @@ static int parse_proc_cmdline_item(const char *key, const char *value) {
                 else {
                         char *n;
 
-                        n = unit_name_mangle(value, MANGLE_NOGLOB);
-                        if (!n)
-                                return log_oom();
+                        r = unit_name_mangle(value, UNIT_NAME_NOGLOB, &n);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to glob unit name: %m");
 
                         r = strv_consume(&arg_mask, n);
                         if (r < 0)
@@ -57,9 +57,9 @@ static int parse_proc_cmdline_item(const char *key, const char *value) {
                 else {
                         char *n;
 
-                        n = unit_name_mangle(value, MANGLE_NOGLOB);
-                        if (!n)
-                                return log_oom();
+                        r = unit_name_mangle(value, UNIT_NAME_NOGLOB, &n);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to glob unit name: %m");
 
                         r = strv_consume(&arg_wants, n);
                         if (r < 0)
diff --git a/src/escape/escape.c b/src/escape/escape.c
index f2a0721861..9ccb015538 100644
--- a/src/escape/escape.c
+++ b/src/escape/escape.c
@@ -99,7 +99,7 @@ static int parse_argv(int argc, char *argv[]) {
 
                 case ARG_TEMPLATE:
 
-                        if (!unit_name_is_valid(optarg, true) || !unit_name_is_template(optarg)) {
+                        if (!unit_name_is_valid(optarg, UNIT_NAME_TEMPLATE)) {
                                 log_error("Template name %s is not valid.", optarg);
                                 return -EINVAL;
                         }
@@ -166,22 +166,26 @@ int main(int argc, char *argv[]) {
                 switch (arg_action) {
 
                 case ACTION_ESCAPE:
-                        if (arg_path)
-                                e = unit_name_path_escape(*i);
-                        else
+                        if (arg_path) {
+                                r = unit_name_path_escape(*i, &e);
+                                if (r < 0) {
+                                        log_error_errno(r, "Failed to escape string: %m");
+                                        goto finish;
+                                }
+                        } else {
                                 e = unit_name_escape(*i);
-
-                        if (!e) {
-                                r = log_oom();
-                                goto finish;
+                                if (!e) {
+                                        r = log_oom();
+                                        goto finish;
+                                }
                         }
 
                         if (arg_template) {
                                 char *x;
 
-                                x = unit_name_replace_instance(arg_template, e);
-                                if (!x) {
-                                        r = log_oom();
+                                r = unit_name_replace_instance(arg_template, e, &x);
+                                if (r < 0) {
+                                        log_error_errno(r, "Failed to replace instance: %m");
                                         goto finish;
                                 }
 
@@ -204,20 +208,20 @@ int main(int argc, char *argv[]) {
 
                 case ACTION_UNESCAPE:
                         if (arg_path)
-                                e = unit_name_path_unescape(*i);
+                                r = unit_name_path_unescape(*i, &e);
                         else
-                                e = unit_name_unescape(*i);
+                                r = unit_name_unescape(*i, &e);
 
-                        if (!e) {
-                                r = log_oom();
+                        if (r < 0) {
+                                log_error_errno(r, "Failed to unescape string: %m");
                                 goto finish;
                         }
                         break;
 
                 case ACTION_MANGLE:
-                        e = unit_name_mangle(*i, MANGLE_NOGLOB);
-                        if (!e) {
-                                r = log_oom();
+                        r = unit_name_mangle(*i, UNIT_NAME_NOGLOB, &e);
+                        if (r < 0) {
+                                log_error_errno(r, "Failed to mangle name: %m");
                                 goto finish;
                         }
                         break;
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 664ee2aa6f..167ec60dc5 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -83,9 +83,9 @@ static int add_swap(
                 opts = filtered;
         }
 
-        name = unit_name_from_path(what, ".swap");
-        if (!name)
-                return log_oom();
+        r = unit_name_from_path(what, ".swap", &name);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         unit = strjoin(arg_dest, "/", name, NULL);
         if (!unit)
@@ -224,9 +224,9 @@ static int add_mount(
                 noauto = nofail = automount = false;
         }
 
-        name = unit_name_from_path(where, ".mount");
-        if (!name)
-                return log_oom();
+        r = unit_name_from_path(where, ".mount", &name);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         unit = strjoin(arg_dest, "/", name, NULL);
         if (!unit)
@@ -290,9 +290,9 @@ static int add_mount(
         }
 
         if (automount) {
-                automount_name = unit_name_from_path(where, ".automount");
-                if (!automount_name)
-                        return log_oom();
+                r = unit_name_from_path(where, ".automount", &automount_name);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to generate unit name: %m");
 
                 automount_unit = strjoin(arg_dest, "/", automount_name, NULL);
                 if (!automount_unit)
diff --git a/src/getty-generator/getty-generator.c b/src/getty-generator/getty-generator.c
index d4688d304f..d23caab44a 100644
--- a/src/getty-generator/getty-generator.c
+++ b/src/getty-generator/getty-generator.c
@@ -50,13 +50,11 @@ static int add_symlink(const char *fservice, const char *tservice) {
 
         r = symlink(from, to);
         if (r < 0) {
+                /* In case console=hvc0 is passed this will very likely result in EEXIST */
                 if (errno == EEXIST)
-                        /* In case console=hvc0 is passed this will very likely result in EEXIST */
                         return 0;
-                else {
-                        log_error_errno(errno, "Failed to create symlink %s: %m", to);
-                        return -errno;
-                }
+
+                return log_error_errno(errno, "Failed to create symlink %s: %m", to);
         }
 
         return 0;
@@ -64,28 +62,30 @@ static int add_symlink(const char *fservice, const char *tservice) {
 
 static int add_serial_getty(const char *tty) {
         _cleanup_free_ char *n = NULL;
+        int r;
 
         assert(tty);
 
         log_debug("Automatically adding serial getty for /dev/%s.", tty);
 
-        n = unit_name_from_path_instance("serial-getty", tty, ".service");
-        if (!n)
-                return log_oom();
+        r = unit_name_from_path_instance("serial-getty", tty, ".service", &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate service name: %m");
 
         return add_symlink("serial-getty@.service", n);
 }
 
 static int add_container_getty(const char *tty) {
         _cleanup_free_ char *n = NULL;
+        int r;
 
         assert(tty);
 
         log_debug("Automatically adding container getty for /dev/pts/%s.", tty);
 
-        n = unit_name_from_path_instance("container-getty", tty, ".service");
-        if (!n)
-                return log_oom();
+        r = unit_name_from_path_instance("container-getty", tty, ".service", &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate service name: %m");
 
         return add_symlink("container-getty@.service", n);
 }
diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index 96a8447efd..b192526186 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -49,14 +49,15 @@ static bool arg_root_rw = false;
 static int add_swap(const char *path) {
         _cleanup_free_ char *name = NULL, *unit = NULL, *lnk = NULL;
         _cleanup_fclose_ FILE *f = NULL;
+        int r;
 
         assert(path);
 
         log_debug("Adding swap: %s", path);
 
-        name = unit_name_from_path(path, ".swap");
-        if (!name)
-                return log_oom();
+        r = unit_name_from_path(path, ".swap", &name);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         unit = strjoin(arg_dest, "/", name, NULL);
         if (!unit)
@@ -100,17 +101,17 @@ static int add_cryptsetup(const char *id, const char *what, bool rw, char **devi
         assert(what);
         assert(device);
 
-        d = unit_name_from_path(what, ".device");
-        if (!d)
-                return log_oom();
+        r = unit_name_from_path(what, ".device", &d);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         e = unit_name_escape(id);
         if (!e)
                 return log_oom();
 
-        n = unit_name_build("systemd-cryptsetup", e, ".service");
-        if (!n)
-                return log_oom();
+        r = unit_name_build("systemd-cryptsetup", e, ".service", &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         p = strjoin(arg_dest, "/", n, NULL);
         if (!p)
@@ -224,9 +225,9 @@ static int add_mount(
                 fstype = NULL;
         }
 
-        unit = unit_name_from_path(where, ".mount");
-        if (!unit)
-                return log_oom();
+        r = unit_name_from_path(where, ".mount", &unit);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         p = strjoin(arg_dest, "/", unit, NULL);
         if (!p)
diff --git a/src/hibernate-resume/hibernate-resume-generator.c b/src/hibernate-resume/hibernate-resume-generator.c
index 0207346b28..9fb6233336 100644
--- a/src/hibernate-resume/hibernate-resume-generator.c
+++ b/src/hibernate-resume/hibernate-resume-generator.c
@@ -32,6 +32,7 @@ static const char *arg_dest = "/tmp";
 static char *arg_resume_dev = NULL;
 
 static int parse_proc_cmdline_item(const char *key, const char *value) {
+
         if (streq(key, "resume") && value) {
                 free(arg_resume_dev);
                 arg_resume_dev = fstab_node_to_udev_node(value);
@@ -44,13 +45,14 @@ static int parse_proc_cmdline_item(const char *key, const char *value) {
 
 static int process_resume(void) {
         _cleanup_free_ char *name = NULL, *lnk = NULL;
+        int r;
 
         if (!arg_resume_dev)
                 return 0;
 
-        name = unit_name_from_path_instance("systemd-hibernate-resume", arg_resume_dev, ".service");
-        if (!name)
-                return log_oom();
+        r = unit_name_from_path_instance("systemd-hibernate-resume", arg_resume_dev, ".service", &name);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate unit name: %m");
 
         lnk = strjoin(arg_dest, "/" SPECIAL_SYSINIT_TARGET ".wants/", name, NULL);
         if (!lnk)
diff --git a/src/journal/journalctl.c b/src/journal/journalctl.c
index 666aa20480..627e43ba35 100644
--- a/src/journal/journalctl.c
+++ b/src/journal/journalctl.c
@@ -1135,9 +1135,9 @@ static int add_units(sd_journal *j) {
         STRV_FOREACH(i, arg_system_units) {
                 _cleanup_free_ char *u = NULL;
 
-                u = unit_name_mangle(*i, MANGLE_GLOB);
-                if (!u)
-                        return log_oom();
+                r = unit_name_mangle(*i, UNIT_NAME_GLOB, &u);
+                if (r < 0)
+                        return r;
 
                 if (string_is_glob(u)) {
                         r = strv_push(&patterns, u);
@@ -1181,9 +1181,9 @@ static int add_units(sd_journal *j) {
         STRV_FOREACH(i, arg_user_units) {
                 _cleanup_free_ char *u = NULL;
 
-                u = unit_name_mangle(*i, MANGLE_GLOB);
-                if (!u)
-                        return log_oom();
+                r = unit_name_mangle(*i, UNIT_NAME_GLOB, &u);
+                if (r < 0)
+                        return r;
 
                 if (string_is_glob(u)) {
                         r = strv_push(&patterns, u);
@@ -1840,9 +1840,8 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
 
         r = add_units(j);
-        strv_free(arg_system_units);
-        strv_free(arg_user_units);
-
+        arg_system_units = strv_free(arg_system_units);
+        arg_user_units = strv_free(arg_user_units);
         if (r < 0) {
                 log_error_errno(r, "Failed to add filter for units: %m");
                 return EXIT_FAILURE;
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index b00e9b17dc..71bff96728 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -378,7 +378,7 @@ static int user_start_slice(User *u) {
                 char lu[DECIMAL_STR_MAX(uid_t) + 1], *slice;
                 sprintf(lu, UID_FMT, u->uid);
 
-                r = build_subslice(SPECIAL_USER_SLICE, lu, &slice);
+                r = slice_build_subslice(SPECIAL_USER_SLICE, lu, &slice);
                 if (r < 0)
                         return r;
 
@@ -411,9 +411,9 @@ static int user_start_service(User *u) {
                 char lu[DECIMAL_STR_MAX(uid_t) + 1], *service;
                 sprintf(lu, UID_FMT, u->uid);
 
-                service = unit_name_build("user", lu, ".service");
-                if (!service)
-                        return log_oom();
+                r = unit_name_build("user", lu, ".service", &service);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to build service name: %m");
 
                 r = manager_start_unit(u->manager, service, &error, &job);
                 if (r < 0) {
diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index ed7221800f..9931e4f1fd 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -1340,6 +1340,29 @@ static int read_only_image(int argc, char *argv[], void *userdata) {
         return 0;
 }
 
+static int make_service_name(const char *name, char **ret) {
+        _cleanup_free_ char *e = NULL;
+        int r;
+
+        assert(name);
+        assert(ret);
+
+        if (!machine_name_is_valid(name)) {
+                log_error("Invalid machine name %s.", name);
+                return -EINVAL;
+        }
+
+        e = unit_name_escape(name);
+        if (!e)
+                return log_oom();
+
+        r = unit_name_build("systemd-nspawn", e, ".service", ret);
+        if (r < 0)
+                return log_error_errno(r, "Failed to build unit name: %m");
+
+        return 0;
+}
+
 static int start_machine(int argc, char *argv[], void *userdata) {
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_(bus_wait_for_jobs_freep) BusWaitForJobs *w = NULL;
@@ -1356,21 +1379,12 @@ static int start_machine(int argc, char *argv[], void *userdata) {
 
         for (i = 1; i < argc; i++) {
                 _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-                _cleanup_free_ char *e = NULL, *unit = NULL;
+                _cleanup_free_ char *unit = NULL;
                 const char *object;
 
-                if (!machine_name_is_valid(argv[i])) {
-                        log_error("Invalid machine name %s.", argv[i]);
-                        return -EINVAL;
-                }
-
-                e = unit_name_escape(argv[i]);
-                if (!e)
-                        return log_oom();
-
-                unit = unit_name_build("systemd-nspawn", e, ".service");
-                if (!unit)
-                        return log_oom();
+                r = make_service_name(argv[i], &unit);
+                if (r < 0)
+                        return r;
 
                 r = sd_bus_call_method(
                                 bus,
@@ -1433,18 +1447,9 @@ static int enable_machine(int argc, char *argv[], void *userdata) {
         for (i = 1; i < argc; i++) {
                 _cleanup_free_ char *e = NULL, *unit = NULL;
 
-                if (!machine_name_is_valid(argv[i])) {
-                        log_error("Invalid machine name %s.", argv[i]);
-                        return -EINVAL;
-                }
-
-                e = unit_name_escape(argv[i]);
-                if (!e)
-                        return log_oom();
-
-                unit = unit_name_build("systemd-nspawn", e, ".service");
-                if (!unit)
-                        return log_oom();
+                r = make_service_name(argv[i], &unit);
+                if (r < 0)
+                        return r;
 
                 r = sd_bus_message_append(m, "s", unit);
                 if (r < 0)
diff --git a/src/run/run.c b/src/run/run.c
index db15ab6219..fcd6b06f7d 100644
--- a/src/run/run.c
+++ b/src/run/run.c
@@ -414,9 +414,9 @@ static int transient_cgroup_set_properties(sd_bus_message *m) {
         if (!isempty(arg_slice)) {
                 _cleanup_free_ char *slice;
 
-                slice = unit_name_mangle_with_suffix(arg_slice, MANGLE_NOGLOB, ".slice");
-                if (!slice)
-                        return -ENOMEM;
+                r = unit_name_mangle_with_suffix(arg_slice, UNIT_NAME_NOGLOB, ".slice", &slice);
+                if (r < 0)
+                        return r;
 
                 r = sd_bus_message_append(m, "(sv)", "Slice", "s", slice);
                 if (r < 0)
@@ -728,9 +728,9 @@ static int start_transient_service(
         }
 
         if (arg_unit) {
-                service = unit_name_mangle_with_suffix(arg_unit, MANGLE_NOGLOB, ".service");
-                if (!service)
-                        return log_oom();
+                r = unit_name_mangle_with_suffix(arg_unit, UNIT_NAME_NOGLOB, ".service", &service);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to mangle unit name: %m");
         } else if (asprintf(&service, "run-"PID_FMT".service", getpid()) < 0)
                 return log_oom();
 
@@ -846,9 +846,9 @@ static int start_transient_scope(
                 return log_oom();
 
         if (arg_unit) {
-                scope = unit_name_mangle_with_suffix(arg_unit, MANGLE_NOGLOB, ".scope");
-                if (!scope)
-                        return log_oom();
+                r = unit_name_mangle_with_suffix(arg_unit, UNIT_NAME_NOGLOB, ".scope", &scope);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to mangle scope name: %m");
         } else if (asprintf(&scope, "run-"PID_FMT".scope", getpid()) < 0)
                 return log_oom();
 
@@ -980,16 +980,16 @@ static int start_transient_timer(
                 return log_oom();
 
         if (arg_unit) {
-                switch(unit_name_to_type(arg_unit)) {
+                switch (unit_name_to_type(arg_unit)) {
 
                 case UNIT_SERVICE:
                         service = strdup(arg_unit);
                         if (!service)
                                 return log_oom();
 
-                        timer = unit_name_change_suffix(service, ".timer");
-                        if (!timer)
-                                return log_oom();
+                        r = unit_name_change_suffix(service, ".timer", &timer);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to change unit suffix: %m");
                         break;
 
                 case UNIT_TIMER:
@@ -997,19 +997,19 @@ static int start_transient_timer(
                         if (!timer)
                                 return log_oom();
 
-                        service = unit_name_change_suffix(timer, ".service");
-                        if (!service)
-                                return log_oom();
+                        r = unit_name_change_suffix(timer, ".service", &service);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to change unit suffix: %m");
                         break;
 
                 default:
-                        service = unit_name_mangle_with_suffix(arg_unit, MANGLE_NOGLOB, ".service");
-                        if (!service)
-                                return log_oom();
+                        r = unit_name_mangle_with_suffix(arg_unit, UNIT_NAME_NOGLOB, ".service", &service);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to mangle unit name: %m");
 
-                        timer = unit_name_mangle_with_suffix(arg_unit, MANGLE_NOGLOB, ".timer");
-                        if (!timer)
-                                return log_oom();
+                        r = unit_name_mangle_with_suffix(arg_unit, UNIT_NAME_NOGLOB, ".timer", &timer);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to mangle unit name: %m");
 
                         break;
                 }
diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index b5e4094f4e..c0b0ca4cf2 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -1154,7 +1154,7 @@ int cg_path_decode_unit(const char *cgroup, char **unit){
         c = strndupa(cgroup, n);
         c = cg_unescape(c);
 
-        if (!unit_name_is_valid(c, TEMPLATE_INVALID))
+        if (!unit_name_is_valid(c, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))
                 return -ENXIO;
 
         s = strdup(c);
@@ -1181,7 +1181,7 @@ static bool valid_slice_name(const char *p, size_t n) {
 
                 c = cg_unescape(buf);
 
-                return unit_name_is_valid(c, TEMPLATE_INVALID);
+                return unit_name_is_valid(c, UNIT_NAME_PLAIN);
         }
 
         return false;
@@ -1638,6 +1638,7 @@ bool cg_controller_is_valid(const char *p, bool allow_named) {
 int cg_slice_to_path(const char *unit, char **ret) {
         _cleanup_free_ char *p = NULL, *s = NULL, *e = NULL;
         const char *dash;
+        int r;
 
         assert(unit);
         assert(ret);
@@ -1652,15 +1653,15 @@ int cg_slice_to_path(const char *unit, char **ret) {
                 return 0;
         }
 
-        if (!unit_name_is_valid(unit, TEMPLATE_INVALID))
+        if (!unit_name_is_valid(unit, UNIT_NAME_PLAIN))
                 return -EINVAL;
 
         if (!endswith(unit, ".slice"))
                 return -EINVAL;
 
-        p = unit_name_to_prefix(unit);
-        if (!p)
-                return -ENOMEM;
+        r = unit_name_to_prefix(unit, &p);
+        if (r < 0)
+                return r;
 
         dash = strchr(p, '-');
 
@@ -1677,7 +1678,7 @@ int cg_slice_to_path(const char *unit, char **ret) {
                         return -EINVAL;
 
                 strcpy(stpncpy(n, p, dash - p), ".slice");
-                if (!unit_name_is_valid(n, TEMPLATE_INVALID))
+                if (!unit_name_is_valid(n, UNIT_NAME_PLAIN))
                         return -EINVAL;
 
                 escaped = cg_escape(n);
diff --git a/src/shared/dropin.c b/src/shared/dropin.c
index d1baad6192..963d05d32e 100644
--- a/src/shared/dropin.c
+++ b/src/shared/dropin.c
@@ -164,7 +164,7 @@ static int iterate_dir(
 }
 
 int unit_file_process_dir(
-                Set * unit_path_cache,
+                Set *unit_path_cache,
                 const char *unit_path,
                 const char *name,
                 const char *suffix,
@@ -174,6 +174,7 @@ int unit_file_process_dir(
                 char ***strv) {
 
         _cleanup_free_ char *path = NULL;
+        int r;
 
         assert(unit_path);
         assert(name);
@@ -184,22 +185,22 @@ int unit_file_process_dir(
                 return log_oom();
 
         if (!unit_path_cache || set_get(unit_path_cache, path))
-                iterate_dir(path, dependency, consumer, arg, strv);
+                (void) iterate_dir(path, dependency, consumer, arg, strv);
 
-        if (unit_name_is_instance(name)) {
+        if (unit_name_is_valid(name, UNIT_NAME_INSTANCE)) {
                 _cleanup_free_ char *template = NULL, *p = NULL;
                 /* Also try the template dir */
 
-                template = unit_name_template(name);
-                if (!template)
-                        return log_oom();
+                r = unit_name_template(name, &template);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to generate template from unit name: %m");
 
                 p = strjoin(unit_path, "/", template, suffix, NULL);
                 if (!p)
                         return log_oom();
 
                 if (!unit_path_cache || set_get(unit_path_cache, p))
-                        iterate_dir(p, dependency, consumer, arg, strv);
+                        (void) iterate_dir(p, dependency, consumer, arg, strv);
         }
 
         return 0;
diff --git a/src/shared/generator.c b/src/shared/generator.c
index 7b2f846175..2dc34bf738 100644
--- a/src/shared/generator.c
+++ b/src/shared/generator.c
@@ -37,6 +37,8 @@ int generator_write_fsck_deps(
                 const char *where,
                 const char *fstype) {
 
+        int r;
+
         assert(f);
         assert(dir);
         assert(what);
@@ -48,7 +50,6 @@ int generator_write_fsck_deps(
         }
 
         if (!isempty(fstype) && !streq(fstype, "auto")) {
-                int r;
                 r = fsck_exists(fstype);
                 if (r == -ENOENT) {
                         /* treat missing check as essentially OK */
@@ -70,9 +71,9 @@ int generator_write_fsck_deps(
         } else {
                 _cleanup_free_ char *fsck = NULL;
 
-                fsck = unit_name_from_path_instance("systemd-fsck", what, ".service");
-                if (!fsck)
-                        return log_oom();
+                r = unit_name_from_path_instance("systemd-fsck", what, ".service", &fsck);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to create fsck service name: %m");
 
                 fprintf(f,
                         "RequiresOverridable=%1$s\n"
@@ -106,8 +107,7 @@ int generator_write_timeouts(
 
         r = parse_sec(timeout, &u);
         if (r < 0) {
-                log_warning("Failed to parse timeout for %s, ignoring: %s",
-                            where, timeout);
+                log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout);
                 return 0;
         }
 
@@ -115,9 +115,9 @@ int generator_write_timeouts(
         if (!node)
                 return log_oom();
 
-        unit = unit_name_from_path(node, ".device");
-        if (!unit)
-                return log_oom();
+        r = unit_name_from_path(node, ".device", &unit);
+        if (r < 0)
+                return log_error_errno(r, "Failed to make unit name from path: %m");
 
         return write_drop_in_format(dir, unit, 50, "device-timeout",
                                     "# Automatically generated by %s\n\n"
diff --git a/src/shared/install-printf.c b/src/shared/install-printf.c
index 9996649424..7c25d36931 100644
--- a/src/shared/install-printf.c
+++ b/src/shared/install-printf.c
@@ -29,30 +29,18 @@
 
 static int specifier_prefix_and_instance(char specifier, void *data, void *userdata, char **ret) {
         InstallInfo *i = userdata;
-        char *n;
 
         assert(i);
 
-        n = unit_name_to_prefix_and_instance(i->name);
-        if (!n)
-                return -ENOMEM;
-
-        *ret = n;
-        return 0;
+        return unit_name_to_prefix_and_instance(i->name, ret);
 }
 
 static int specifier_prefix(char specifier, void *data, void *userdata, char **ret) {
         InstallInfo *i = userdata;
-        char *n;
 
         assert(i);
 
-        n = unit_name_to_prefix(i->name);
-        if (!n)
-                return -ENOMEM;
-
-        *ret = n;
-        return 0;
+        return unit_name_to_prefix(i->name, ret);
 }
 
 static int specifier_instance(char specifier, void *data, void *userdata, char **ret) {
diff --git a/src/shared/install.c b/src/shared/install.c
index b121018e97..9648c641d7 100644
--- a/src/shared/install.c
+++ b/src/shared/install.c
@@ -258,10 +258,10 @@ static int remove_marked_symlinks_fd(
                         int q;
                         bool found;
 
-                        if (!unit_name_is_valid(de->d_name, TEMPLATE_VALID))
+                        if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY))
                                 continue;
 
-                        if (unit_name_is_instance(de->d_name) &&
+                        if (unit_name_is_valid(de->d_name, UNIT_NAME_INSTANCE) &&
                             instance_whitelist &&
                             !strv_contains(instance_whitelist, de->d_name)) {
 
@@ -272,9 +272,9 @@ static int remove_marked_symlinks_fd(
                                  * the template of it might be
                                  * listed. */
 
-                                w = unit_name_template(de->d_name);
-                                if (!w)
-                                        return -ENOMEM;
+                                r = unit_name_template(de->d_name, &w);
+                                if (r < 0)
+                                        return r;
 
                                 if (!strv_contains(instance_whitelist, w))
                                         continue;
@@ -583,7 +583,7 @@ int unit_file_mask(
         STRV_FOREACH(i, files) {
                 _cleanup_free_ char *path = NULL;
 
-                if (!unit_name_is_valid(*i, TEMPLATE_VALID)) {
+                if (!unit_name_is_valid(*i, UNIT_NAME_ANY)) {
                         if (r == 0)
                                 r = -EINVAL;
                         continue;
@@ -646,7 +646,7 @@ int unit_file_unmask(
         STRV_FOREACH(i, files) {
                 _cleanup_free_ char *path = NULL;
 
-                if (!unit_name_is_valid(*i, TEMPLATE_VALID)) {
+                if (!unit_name_is_valid(*i, UNIT_NAME_ANY)) {
                         if (r == 0)
                                 r = -EINVAL;
                         continue;
@@ -717,7 +717,7 @@ int unit_file_link(
                 fn = basename(*i);
 
                 if (!path_is_absolute(*i) ||
-                    !unit_name_is_valid(fn, TEMPLATE_VALID)) {
+                    !unit_name_is_valid(fn, UNIT_NAME_ANY)) {
                         if (r == 0)
                                 r = -EINVAL;
                         continue;
@@ -856,7 +856,7 @@ static int install_info_add(
         if (!name)
                 name = basename(path);
 
-        if (!unit_name_is_valid(name, TEMPLATE_VALID))
+        if (!unit_name_is_valid(name, UNIT_NAME_ANY))
                 return -EINVAL;
 
         if (ordered_hashmap_get(c->have_installed, name) ||
@@ -1118,7 +1118,7 @@ static int unit_file_search(
                         return r;
         }
 
-        if (unit_name_is_instance(info->name)) {
+        if (unit_name_is_valid(info->name, UNIT_NAME_INSTANCE)) {
 
                 /* Unit file doesn't exist, however instance
                  * enablement was requested.  We will check if it is
@@ -1126,9 +1126,9 @@ static int unit_file_search(
 
                 _cleanup_free_ char *template = NULL;
 
-                template = unit_name_template(info->name);
-                if (!template)
-                        return -ENOMEM;
+                r = unit_name_template(info->name, &template);
+                if (r < 0)
+                        return r;
 
                 STRV_FOREACH(p, paths->unit_path) {
                         _cleanup_free_ char *path = NULL;
@@ -1274,7 +1274,7 @@ static int install_info_symlink_wants(
         assert(i);
         assert(config_path);
 
-        if (unit_name_is_template(i->name)) {
+        if (unit_name_is_valid(i->name, UNIT_NAME_TEMPLATE)) {
 
                 /* Don't install any symlink if there's no default
                  * instance configured */
@@ -1282,9 +1282,9 @@ static int install_info_symlink_wants(
                 if (!i->default_instance)
                         return 0;
 
-                buf = unit_name_replace_instance(i->name, i->default_instance);
-                if (!buf)
-                        return -ENOMEM;
+                r = unit_name_replace_instance(i->name, i->default_instance, &buf);
+                if (r < 0)
+                        return r;
 
                 n = buf;
         } else
@@ -1297,7 +1297,7 @@ static int install_info_symlink_wants(
                 if (q < 0)
                         return q;
 
-                if (!unit_name_is_valid(dst, TEMPLATE_VALID)) {
+                if (!unit_name_is_valid(dst, UNIT_NAME_ANY)) {
                         r = -EINVAL;
                         continue;
                 }
@@ -1462,13 +1462,13 @@ static int install_context_mark_for_removal(
                 } else if (r >= 0)
                         r += q;
 
-                if (unit_name_is_instance(i->name)) {
+                if (unit_name_is_valid(i->name, UNIT_NAME_INSTANCE)) {
                         char *unit_file;
 
                         if (i->path) {
                                 unit_file = basename(i->path);
 
-                                if (unit_name_is_instance(unit_file))
+                                if (unit_name_is_valid(unit_file, UNIT_NAME_INSTANCE))
                                         /* unit file named as instance exists, thus all symlinks
                                          * pointing to it will be removed */
                                         q = mark_symlink_for_removal(remove_symlinks_to, i->name);
@@ -1480,9 +1480,9 @@ static int install_context_mark_for_removal(
                                 /* If i->path is not set, it means that we didn't actually find
                                  * the unit file. But we can still remove symlinks to the
                                  * nonexistent template. */
-                                unit_file = unit_name_template(i->name);
-                                if (!unit_file)
-                                        return log_oom();
+                                r = unit_name_template(i->name, &unit_file);
+                                if (r < 0)
+                                        return r;
 
                                 q = mark_symlink_for_removal(remove_symlinks_to, unit_file);
                                 free(unit_file);
@@ -1797,7 +1797,7 @@ UnitFileState unit_file_lookup_state(
 
         assert(paths);
 
-        if (!unit_name_is_valid(name, TEMPLATE_VALID))
+        if (!unit_name_is_valid(name, UNIT_NAME_ANY))
                 return -EINVAL;
 
         STRV_FOREACH(i, paths->unit_path) {
@@ -1824,7 +1824,7 @@ UnitFileState unit_file_lookup_state(
                         if (errno != ENOENT)
                                 return r;
 
-                        if (!unit_name_is_instance(name))
+                        if (!unit_name_is_valid(name, UNIT_NAME_INSTANCE))
                                 continue;
                 } else {
                         if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode))
@@ -1834,8 +1834,7 @@ UnitFileState unit_file_lookup_state(
                         if (r < 0 && r != -ENOENT)
                                 return r;
                         else if (r > 0) {
-                                state = path_startswith(*i, "/run") ?
-                                        UNIT_FILE_MASKED_RUNTIME : UNIT_FILE_MASKED;
+                                state = path_startswith(*i, "/run") ? UNIT_FILE_MASKED_RUNTIME : UNIT_FILE_MASKED;
                                 return state;
                         }
                 }
@@ -1995,7 +1994,7 @@ int unit_file_preset(
 
         STRV_FOREACH(i, files) {
 
-                if (!unit_name_is_valid(*i, TEMPLATE_VALID))
+                if (!unit_name_is_valid(*i, UNIT_NAME_ANY))
                         return -EINVAL;
 
                 r = unit_file_query_preset(scope, root_dir, *i);
@@ -2091,7 +2090,7 @@ int unit_file_preset_all(
                         if (hidden_file(de->d_name))
                                 continue;
 
-                        if (!unit_name_is_valid(de->d_name, TEMPLATE_VALID))
+                        if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY))
                                 continue;
 
                         dirent_ensure_type(d, de);
@@ -2203,7 +2202,7 @@ int unit_file_get_list(
                         if (hidden_file(de->d_name))
                                 continue;
 
-                        if (!unit_name_is_valid(de->d_name, TEMPLATE_VALID))
+                        if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY))
                                 continue;
 
                         if (hashmap_get(h, de->d_name))
diff --git a/src/shared/unit-name.c b/src/shared/unit-name.c
index 86d6ce3df1..c41d7d86a7 100644
--- a/src/shared/unit-name.c
+++ b/src/shared/unit-name.c
@@ -33,45 +33,13 @@
         DIGITS LETTERS                          \
         ":-_.\\"
 
-static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
-        [UNIT_SERVICE] = "service",
-        [UNIT_SOCKET] = "socket",
-        [UNIT_BUSNAME] = "busname",
-        [UNIT_TARGET] = "target",
-        [UNIT_SNAPSHOT] = "snapshot",
-        [UNIT_DEVICE] = "device",
-        [UNIT_MOUNT] = "mount",
-        [UNIT_AUTOMOUNT] = "automount",
-        [UNIT_SWAP] = "swap",
-        [UNIT_TIMER] = "timer",
-        [UNIT_PATH] = "path",
-        [UNIT_SLICE] = "slice",
-        [UNIT_SCOPE] = "scope"
-};
-
-DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
-
-static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
-        [UNIT_STUB] = "stub",
-        [UNIT_LOADED] = "loaded",
-        [UNIT_NOT_FOUND] = "not-found",
-        [UNIT_ERROR] = "error",
-        [UNIT_MERGED] = "merged",
-        [UNIT_MASKED] = "masked"
-};
-
-DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
-
-bool unit_name_is_valid(const char *n, enum template_valid template_ok) {
+bool unit_name_is_valid(const char *n, UnitNameFlags flags) {
         const char *e, *i, *at;
 
-        /* Valid formats:
-         *
-         *         string@instance.suffix
-         *         string.suffix
-         */
+        assert((flags & ~(UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE)) == 0);
 
-        assert(IN_SET(template_ok, TEMPLATE_VALID, TEMPLATE_INVALID));
+        if (_unlikely_(flags == 0))
+                return false;
 
         if (isempty(n))
                 return false;
@@ -95,15 +63,32 @@ bool unit_name_is_valid(const char *n, enum template_valid template_ok) {
                         return false;
         }
 
-        if (at) {
-                if (at == n)
-                        return false;
+        if (at == n)
+                return false;
 
-                if (template_ok != TEMPLATE_VALID && at+1 == e)
-                        return false;
-        }
+        if (flags & UNIT_NAME_PLAIN)
+                if (!at)
+                        return true;
 
-        return true;
+        if (flags & UNIT_NAME_INSTANCE)
+                if (at && e > at + 1)
+                        return true;
+
+        if (flags & UNIT_NAME_TEMPLATE)
+                if (at && e == at + 1)
+                        return true;
+
+        return false;
+}
+
+bool unit_prefix_is_valid(const char *p) {
+
+        /* We don't allow additional @ in the prefix string */
+
+        if (isempty(p))
+                return false;
+
+        return in_charset(p, VALID_CHARS);
 }
 
 bool unit_instance_is_valid(const char *i) {
@@ -120,14 +105,41 @@ bool unit_instance_is_valid(const char *i) {
         return in_charset(i, "@" VALID_CHARS);
 }
 
-bool unit_prefix_is_valid(const char *p) {
+bool unit_suffix_is_valid(const char *s) {
+        if (isempty(s))
+                return false;
 
-        /* We don't allow additional @ in the instance string */
+        if (s[0] != '.')
+                return false;
 
-        if (isempty(p))
+        if (unit_type_from_string(s + 1) < 0)
                 return false;
 
-        return in_charset(p, VALID_CHARS);
+        return true;
+}
+
+int unit_name_to_prefix(const char *n, char **ret) {
+        const char *p;
+        char *s;
+
+        assert(n);
+        assert(ret);
+
+        if (!unit_name_is_valid(n, UNIT_NAME_ANY))
+                return -EINVAL;
+
+        p = strchr(n, '@');
+        if (!p)
+                p = strrchr(n, '.');
+
+        assert_se(p);
+
+        s = strndup(n, p - n);
+        if (!s)
+                return -ENOMEM;
+
+        *ret = s;
+        return 0;
 }
 
 int unit_name_to_instance(const char *n, char **instance) {
@@ -137,6 +149,9 @@ int unit_name_to_instance(const char *n, char **instance) {
         assert(n);
         assert(instance);
 
+        if (!unit_name_is_valid(n, UNIT_NAME_ANY))
+                return -EINVAL;
+
         /* Everything past the first @ and before the last . is the instance */
         p = strchr(n, '@');
         if (!p) {
@@ -144,13 +159,13 @@ int unit_name_to_instance(const char *n, char **instance) {
                 return 0;
         }
 
-        d = strrchr(n, '.');
+        p++;
+
+        d = strrchr(p, '.');
         if (!d)
                 return -EINVAL;
-        if (d < p)
-                return -EINVAL;
 
-        i = strndup(p+1, d-p-1);
+        i = strndup(p, d-p);
         if (!i)
                 return -ENOMEM;
 
@@ -158,55 +173,95 @@ int unit_name_to_instance(const char *n, char **instance) {
         return 1;
 }
 
-char *unit_name_to_prefix_and_instance(const char *n) {
+int unit_name_to_prefix_and_instance(const char *n, char **ret) {
         const char *d;
+        char *s;
 
         assert(n);
+        assert(ret);
+
+        if (!unit_name_is_valid(n, UNIT_NAME_ANY))
+                return -EINVAL;
 
-        assert_se(d = strrchr(n, '.'));
-        return strndup(n, d - n);
+        d = strrchr(n, '.');
+        if (!d)
+                return -EINVAL;
+
+        s = strndup(n, d - n);
+        if (!s)
+                return -ENOMEM;
+
+        *ret = s;
+        return 0;
 }
 
-char *unit_name_to_prefix(const char *n) {
-        const char *p;
+UnitType unit_name_to_type(const char *n) {
+        const char *e;
 
         assert(n);
 
-        p = strchr(n, '@');
-        if (p)
-                return strndup(n, p - n);
+        if (!unit_name_is_valid(n, UNIT_NAME_ANY))
+                return _UNIT_TYPE_INVALID;
 
-        return unit_name_to_prefix_and_instance(n);
+        assert_se(e = strrchr(n, '.'));
+
+        return unit_type_from_string(e + 1);
 }
 
-char *unit_name_change_suffix(const char *n, const char *suffix) {
-        char *e, *r;
+int unit_name_change_suffix(const char *n, const char *suffix, char **ret) {
+        char *e, *s;
         size_t a, b;
 
         assert(n);
         assert(suffix);
-        assert(suffix[0] == '.');
+        assert(ret);
+
+        if (!unit_name_is_valid(n, UNIT_NAME_ANY))
+                return -EINVAL;
+
+        if (!unit_suffix_is_valid(suffix))
+                return -EINVAL;
 
         assert_se(e = strrchr(n, '.'));
+
         a = e - n;
         b = strlen(suffix);
 
-        r = new(char, a + b + 1);
-        if (!r)
-                return NULL;
+        s = new(char, a + b + 1);
+        if (!s)
+                return -ENOMEM;
 
-        strcpy(mempcpy(r, n, a), suffix);
-        return r;
+        strcpy(mempcpy(s, n, a), suffix);
+        *ret = s;
+
+        return 0;
 }
 
-char *unit_name_build(const char *prefix, const char *instance, const char *suffix) {
+int unit_name_build(const char *prefix, const char *instance, const char *suffix, char **ret) {
+        char *s;
+
         assert(prefix);
         assert(suffix);
+        assert(ret);
+
+        if (!unit_prefix_is_valid(prefix))
+                return -EINVAL;
+
+        if (instance && !unit_instance_is_valid(instance))
+                return -EINVAL;
+
+        if (!unit_suffix_is_valid(suffix))
+                return -EINVAL;
 
         if (!instance)
-                return strappend(prefix, suffix);
+                s = strappend(prefix, suffix);
+        else
+                s = strjoin(prefix, "@", instance, suffix, NULL);
+        if (!s)
+                return -ENOMEM;
 
-        return strjoin(prefix, "@", instance, suffix, NULL);
+        *ret = s;
+        return 0;
 }
 
 static char *do_escape_char(char c, char *t) {
@@ -242,30 +297,6 @@ static char *do_escape(const char *f, char *t) {
         return t;
 }
 
-static char *do_escape_mangle(const char *f, enum unit_name_mangle allow_globs, char *t) {
-        const char *valid_chars;
-
-        assert(f);
-        assert(IN_SET(allow_globs, MANGLE_GLOB, MANGLE_NOGLOB));
-        assert(t);
-
-        /* We'll only escape the obvious characters here, to play
-         * safe. */
-
-        valid_chars = allow_globs == MANGLE_GLOB ? "@" VALID_CHARS "[]!-*?" : "@" VALID_CHARS;
-
-        for (; *f; f++) {
-                if (*f == '/')
-                        *(t++) = '-';
-                else if (!strchr(valid_chars, *f))
-                        t = do_escape_char(*f, t);
-                else
-                        *(t++) = *f;
-        }
-
-        return t;
-}
-
 char *unit_name_escape(const char *f) {
         char *r, *t;
 
@@ -281,14 +312,15 @@ char *unit_name_escape(const char *f) {
         return r;
 }
 
-char *unit_name_unescape(const char *f) {
-        char *r, *t;
+int unit_name_unescape(const char *f, char **ret) {
+        _cleanup_free_ char *r = NULL;
+        char *t;
 
         assert(f);
 
         r = strdup(f);
         if (!r)
-                return NULL;
+                return -ENOMEM;
 
         for (t = r; *f; f++) {
                 if (*f == '-')
@@ -296,180 +328,228 @@ char *unit_name_unescape(const char *f) {
                 else if (*f == '\\') {
                         int a, b;
 
-                        if (f[1] != 'x' ||
-                            (a = unhexchar(f[2])) < 0 ||
-                            (b = unhexchar(f[3])) < 0) {
-                                /* Invalid escape code, let's take it literal then */
-                                *(t++) = '\\';
-                        } else {
-                                *(t++) = (char) ((a << 4) | b);
-                                f += 3;
-                        }
+                        if (f[1] != 'x')
+                                return -EINVAL;
+
+                        a = unhexchar(f[2]);
+                        if (a < 0)
+                                return -EINVAL;
+
+                        b = unhexchar(f[3]);
+                        if (b < 0)
+                                return -EINVAL;
+
+                        *(t++) = (char) ((a << 4) | b);
+                        f += 3;
                 } else
                         *(t++) = *f;
         }
 
         *t = 0;
 
-        return r;
+        *ret = r;
+        r = NULL;
+
+        return 0;
 }
 
-char *unit_name_path_escape(const char *f) {
-        _cleanup_free_ char *p = NULL;
+int unit_name_path_escape(const char *f, char **ret) {
+        char *p, *s;
 
         assert(f);
+        assert(ret);
 
-        p = strdup(f);
+        p = strdupa(f);
         if (!p)
-                return NULL;
+                return -ENOMEM;
 
         path_kill_slashes(p);
 
         if (STR_IN_SET(p, "/", ""))
-                return strdup("-");
-
-        return unit_name_escape(p[0] == '/' ? p + 1 : p);
-}
+                s = strdup("-");
+        else {
+                char *e;
 
-char *unit_name_path_unescape(const char *f) {
-        char *e, *w;
+                if (!path_is_safe(p))
+                        return -EINVAL;
 
-        assert(f);
+                /* Truncate trailing slashes */
+                e = endswith(p, "/");
+                if (e)
+                        *e = 0;
 
-        e = unit_name_unescape(f);
-        if (!e)
-                return NULL;
+                /* Truncate leading slashes */
+                if (p[0] == '/')
+                        p++;
 
-        if (e[0] != '/') {
-                w = strappend("/", e);
-                free(e);
-                return w;
+                s = unit_name_escape(p);
         }
+        if (!s)
+                return -ENOMEM;
 
-        return e;
+        *ret = s;
+        return 0;
 }
 
-bool unit_name_is_template(const char *n) {
-        const char *p, *e;
-
-        assert(n);
+int unit_name_path_unescape(const char *f, char **ret) {
+        char *s, *w;
+        int r;
 
-        p = strchr(n, '@');
-        if (!p)
-                return false;
+        assert(f);
 
-        e = strrchr(p+1, '.');
-        if (!e)
-                return false;
+        if (streq(f, "-")) {
+                s = strdup("/");
+                if (!s)
+                        return -ENOMEM;
 
-        return e == p + 1;
-}
+                *ret = s;
+                return 0;
+        }
 
-bool unit_name_is_instance(const char *n) {
-        const char *p, *e;
+        r = unit_name_unescape(f, &s);
+        if (r < 0)
+                return r;
 
-        assert(n);
+        /* Don't accept trailing or leading slashes */
+        if (startswith(s, "/") || endswith(s, "/")) {
+                free(s);
+                return -EINVAL;
+        }
 
-        p = strchr(n, '@');
-        if (!p)
-                return false;
+        /* Prefix a slash again */
+        w = strappend("/", s);
+        free(s);
+        if (!w)
+                return -ENOMEM;
 
-        e = strrchr(p+1, '.');
-        if (!e)
-                return false;
+        if (!path_is_safe(w)) {
+                free(w);
+                return -EINVAL;
+        }
 
-        return e > p + 1;
+        *ret = w;
+        return 0;
 }
 
-char *unit_name_replace_instance(const char *f, const char *i) {
+int unit_name_replace_instance(const char *f, const char *i, char **ret) {
         const char *p, *e;
-        char *r;
+        char *s;
         size_t a, b;
 
         assert(f);
         assert(i);
+        assert(ret);
 
-        p = strchr(f, '@');
-        if (!p)
-                return strdup(f);
+        if (!unit_name_is_valid(f, UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE))
+                return -EINVAL;
+        if (!unit_instance_is_valid(i))
+                return -EINVAL;
 
-        e = strrchr(f, '.');
-        if (!e)
-                e = strchr(f, 0);
+        assert_se(p = strchr(f, '@'));
+        assert_se(e = strrchr(f, '.'));
 
         a = p - f;
         b = strlen(i);
 
-        r = new(char, a + 1 + b + strlen(e) + 1);
-        if (!r)
-                return NULL;
+        s = new(char, a + 1 + b + strlen(e) + 1);
+        if (!s)
+                return -ENOMEM;
 
-        strcpy(mempcpy(mempcpy(r, f, a + 1), i, b), e);
-        return r;
+        strcpy(mempcpy(mempcpy(s, f, a + 1), i, b), e);
+
+        *ret = s;
+        return 0;
 }
 
-char *unit_name_template(const char *f) {
+int unit_name_template(const char *f, char **ret) {
         const char *p, *e;
-        char *r;
+        char *s;
         size_t a;
 
         assert(f);
+        assert(ret);
 
-        p = strchr(f, '@');
-        if (!p)
-                return strdup(f);
+        if (!unit_name_is_valid(f, UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE))
+                return -EINVAL;
 
-        e = strrchr(f, '.');
-        if (!e)
-                e = strchr(f, 0);
+        assert_se(p = strchr(f, '@'));
+        assert_se(e = strrchr(f, '.'));
 
         a = p - f;
 
-        r = new(char, a + 1 + strlen(e) + 1);
-        if (!r)
-                return NULL;
+        s = new(char, a + 1 + strlen(e) + 1);
+        if (!s)
+                return -ENOMEM;
 
-        strcpy(mempcpy(r, f, a + 1), e);
-        return r;
+        strcpy(mempcpy(s, f, a + 1), e);
+
+        *ret = s;
+        return 0;
 }
 
-char *unit_name_from_path(const char *path, const char *suffix) {
+int unit_name_from_path(const char *path, const char *suffix, char **ret) {
         _cleanup_free_ char *p = NULL;
+        char *s = NULL;
+        int r;
 
         assert(path);
         assert(suffix);
+        assert(ret);
 
-        p = unit_name_path_escape(path);
-        if (!p)
-                return NULL;
+        if (!unit_suffix_is_valid(suffix))
+                return -EINVAL;
 
-        return strappend(p, suffix);
+        r = unit_name_path_escape(path, &p);
+        if (r < 0)
+                return r;
+
+        s = strappend(p, suffix);
+        if (!s)
+                return -ENOMEM;
+
+        *ret = s;
+        return 0;
 }
 
-char *unit_name_from_path_instance(const char *prefix, const char *path, const char *suffix) {
+int unit_name_from_path_instance(const char *prefix, const char *path, const char *suffix, char **ret) {
         _cleanup_free_ char *p = NULL;
+        char *s;
+        int r;
 
         assert(prefix);
         assert(path);
         assert(suffix);
+        assert(ret);
 
-        p = unit_name_path_escape(path);
-        if (!p)
-                return NULL;
+        if (!unit_prefix_is_valid(prefix))
+                return -EINVAL;
+
+        if (!unit_suffix_is_valid(suffix))
+                return -EINVAL;
+
+        r = unit_name_path_escape(path, &p);
+        if (r < 0)
+                return r;
+
+        s = strjoin(prefix, "@", p, suffix, NULL);
+        if (!s)
+                return -ENOMEM;
 
-        return strjoin(prefix, "@", p, suffix, NULL);
+        *ret = s;
+        return 0;
 }
 
-char *unit_name_to_path(const char *name) {
-        _cleanup_free_ char *w = NULL;
+int unit_name_to_path(const char *name, char **ret) {
+        _cleanup_free_ char *prefix = NULL;
+        int r;
 
         assert(name);
 
-        w = unit_name_to_prefix(name);
-        if (!w)
-                return NULL;
+        r = unit_name_to_prefix(name, &prefix);
+        if (r < 0)
+                return r;
 
-        return unit_name_path_unescape(w);
+        return unit_name_path_unescape(prefix, ret);
 }
 
 char *unit_dbus_path_from_name(const char *name) {
@@ -500,6 +580,30 @@ int unit_name_from_dbus_path(const char *path, char **name) {
         return 0;
 }
 
+static char *do_escape_mangle(const char *f, UnitNameMangle allow_globs, char *t) {
+        const char *valid_chars;
+
+        assert(f);
+        assert(IN_SET(allow_globs, UNIT_NAME_GLOB, UNIT_NAME_NOGLOB));
+        assert(t);
+
+        /* We'll only escape the obvious characters here, to play
+         * safe. */
+
+        valid_chars = allow_globs == UNIT_NAME_GLOB ? "@" VALID_CHARS "[]!-*?" : "@" VALID_CHARS;
+
+        for (; *f; f++) {
+                if (*f == '/')
+                        *(t++) = '-';
+                else if (!strchr(valid_chars, *f))
+                        t = do_escape_char(*f, t);
+                else
+                        *(t++) = *f;
+        }
+
+        return t;
+}
+
 /**
  *  Convert a string to a unit name. /dev/blah is converted to dev-blah.device,
  *  /blah/blah is converted to blah-blah.mount, anything else is left alone,
@@ -507,54 +611,75 @@ int unit_name_from_dbus_path(const char *path, char **name) {
  *
  *  If @allow_globs, globs characters are preserved. Otherwise they are escaped.
  */
-char *unit_name_mangle_with_suffix(const char *name, enum unit_name_mangle allow_globs, const char *suffix) {
-        char *r, *t;
+int unit_name_mangle_with_suffix(const char *name, UnitNameMangle allow_globs, const char *suffix, char **ret) {
+        char *s, *t;
+        int r;
 
         assert(name);
         assert(suffix);
-        assert(suffix[0] == '.');
+        assert(ret);
 
-        if (is_device_path(name))
-                return unit_name_from_path(name, ".device");
+        if (isempty(name)) /* We cannot mangle empty unit names to become valid, sorry. */
+                return -EINVAL;
 
-        if (path_is_absolute(name))
-                return unit_name_from_path(name, ".mount");
+        if (!unit_suffix_is_valid(suffix))
+                return -EINVAL;
 
-        r = new(char, strlen(name) * 4 + strlen(suffix) + 1);
-        if (!r)
-                return NULL;
+        if (unit_name_is_valid(name, UNIT_NAME_ANY)) {
+                /* No mangling necessary... */
+                s = strdup(name);
+                if (!s)
+                        return -ENOMEM;
 
-        t = do_escape_mangle(name, allow_globs, r);
+                *ret = s;
+                return 0;
+        }
 
-        if (unit_name_to_type(name) < 0)
-                strcpy(t, suffix);
-        else
-                *t = 0;
+        if (is_device_path(name)) {
+                r = unit_name_from_path(name, ".device", ret);
+                if (r >= 0)
+                        return 1;
+                if (r != -EINVAL)
+                        return r;
+        }
 
-        return r;
-}
+        if (path_is_absolute(name)) {
+                r = unit_name_from_path(name, ".mount", ret);
+                if (r >= 0)
+                        return 1;
+                if (r != -EINVAL)
+                        return r;
+        }
 
-UnitType unit_name_to_type(const char *n) {
-        const char *e;
+        s = new(char, strlen(name) * 4 + strlen(suffix) + 1);
+        if (!s)
+                return -ENOMEM;
 
-        assert(n);
+        t = do_escape_mangle(name, allow_globs, s);
+        *t = 0;
 
-        e = strrchr(n, '.');
-        if (!e)
-                return _UNIT_TYPE_INVALID;
+        if (unit_name_to_type(s) < 0)
+                strcpy(t, suffix);
 
-        return unit_type_from_string(e + 1);
+        *ret = s;
+        return 1;
 }
 
-int build_subslice(const char *slice, const char*name, char **subslice) {
-        char *ret;
+int slice_build_subslice(const char *slice, const char*name, char **ret) {
+        char *subslice;
 
         assert(slice);
         assert(name);
-        assert(subslice);
+        assert(ret);
+
+        if (!unit_name_is_valid(slice, UNIT_NAME_PLAIN))
+                return -EINVAL;
+
+        if (!unit_prefix_is_valid(name))
+                return -EINVAL;
 
         if (streq(slice, "-.slice"))
-                ret = strappend(name, ".slice");
+                subslice = strappend(name, ".slice");
         else {
                 char *e;
 
@@ -562,17 +687,46 @@ int build_subslice(const char *slice, const char*name, char **subslice) {
                 if (!e)
                         return -EINVAL;
 
-                ret = new(char, (e - slice) + 1 + strlen(name) + 6 + 1);
-                if (!ret)
+                subslice = new(char, (e - slice) + 1 + strlen(name) + 6 + 1);
+                if (!subslice)
                         return -ENOMEM;
 
-                stpcpy(stpcpy(stpcpy(mempcpy(ret, slice, e - slice), "-"), name), ".slice");
+                stpcpy(stpcpy(stpcpy(mempcpy(subslice, slice, e - slice), "-"), name), ".slice");
         }
 
-        *subslice = ret;
+        *ret = subslice;
         return 0;
 }
 
+static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
+        [UNIT_SERVICE] = "service",
+        [UNIT_SOCKET] = "socket",
+        [UNIT_BUSNAME] = "busname",
+        [UNIT_TARGET] = "target",
+        [UNIT_SNAPSHOT] = "snapshot",
+        [UNIT_DEVICE] = "device",
+        [UNIT_MOUNT] = "mount",
+        [UNIT_AUTOMOUNT] = "automount",
+        [UNIT_SWAP] = "swap",
+        [UNIT_TIMER] = "timer",
+        [UNIT_PATH] = "path",
+        [UNIT_SLICE] = "slice",
+        [UNIT_SCOPE] = "scope"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
+
+static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
+        [UNIT_STUB] = "stub",
+        [UNIT_LOADED] = "loaded",
+        [UNIT_NOT_FOUND] = "not-found",
+        [UNIT_ERROR] = "error",
+        [UNIT_MERGED] = "merged",
+        [UNIT_MASKED] = "masked"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
+
 static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
         [UNIT_REQUIRES] = "Requires",
         [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
diff --git a/src/shared/unit-name.h b/src/shared/unit-name.h
index 6f139cc4c4..057512cbd3 100644
--- a/src/shared/unit-name.h
+++ b/src/shared/unit-name.h
@@ -107,61 +107,67 @@ enum UnitDependency {
         _UNIT_DEPENDENCY_INVALID = -1
 };
 
-const char *unit_type_to_string(UnitType i) _const_;
-UnitType unit_type_from_string(const char *s) _pure_;
+typedef enum UnitNameFlags {
+        UNIT_NAME_PLAIN = 1,      /* Allow foo.service */
+        UNIT_NAME_INSTANCE = 2,   /* Allow foo@bar.service */
+        UNIT_NAME_TEMPLATE = 4,   /* Allow foo@.service */
+        UNIT_NAME_ANY = UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE,
+} UnitNameFlags;
+
+bool unit_name_is_valid(const char *n, UnitNameFlags flags) _pure_;
+bool unit_prefix_is_valid(const char *p) _pure_;
+bool unit_instance_is_valid(const char *i) _pure_;
+bool unit_suffix_is_valid(const char *s) _pure_;
 
-const char *unit_load_state_to_string(UnitLoadState i) _const_;
-UnitLoadState unit_load_state_from_string(const char *s) _pure_;
+static inline int unit_prefix_and_instance_is_valid(const char *p) {
+        /* For prefix+instance and instance the same rules apply */
+        return unit_instance_is_valid(p);
+}
 
+int unit_name_to_prefix(const char *n, char **prefix);
 int unit_name_to_instance(const char *n, char **instance);
-char* unit_name_to_prefix(const char *n);
-char* unit_name_to_prefix_and_instance(const char *n);
-
-enum template_valid {
-        TEMPLATE_INVALID,
-        TEMPLATE_VALID,
-};
-
-bool unit_name_is_valid(const char *n, enum template_valid template_ok) _pure_;
-bool unit_prefix_is_valid(const char *p) _pure_;
-bool unit_instance_is_valid(const char *i) _pure_;
+int unit_name_to_prefix_and_instance(const char *n, char **ret);
 
 UnitType unit_name_to_type(const char *n) _pure_;
 
-char *unit_name_change_suffix(const char *n, const char *suffix);
+int unit_name_change_suffix(const char *n, const char *suffix, char **ret);
 
-char *unit_name_build(const char *prefix, const char *instance, const char *suffix);
+int unit_name_build(const char *prefix, const char *instance, const char *suffix, char **ret);
 
 char *unit_name_escape(const char *f);
-char *unit_name_unescape(const char *f);
-char *unit_name_path_escape(const char *f);
-char *unit_name_path_unescape(const char *f);
-
-bool unit_name_is_template(const char *n) _pure_;
-bool unit_name_is_instance(const char *n) _pure_;
+int unit_name_unescape(const char *f, char **ret);
+int unit_name_path_escape(const char *f, char **ret);
+int unit_name_path_unescape(const char *f, char **ret);
 
-char *unit_name_replace_instance(const char *f, const char *i);
+int unit_name_replace_instance(const char *f, const char *i, char **ret);
 
-char *unit_name_template(const char *f);
+int unit_name_template(const char *f, char **ret);
 
-char *unit_name_from_path(const char *path, const char *suffix);
-char *unit_name_from_path_instance(const char *prefix, const char *path, const char *suffix);
-char *unit_name_to_path(const char *name);
+int unit_name_from_path(const char *path, const char *suffix, char **ret);
+int unit_name_from_path_instance(const char *prefix, const char *path, const char *suffix, char **ret);
+int unit_name_to_path(const char *name, char **ret);
 
 char *unit_dbus_path_from_name(const char *name);
 int unit_name_from_dbus_path(const char *path, char **name);
 
-enum unit_name_mangle {
-        MANGLE_NOGLOB,
-        MANGLE_GLOB,
-};
+typedef enum UnitNameMangle {
+        UNIT_NAME_NOGLOB,
+        UNIT_NAME_GLOB,
+} UnitNameMangle;
 
-char *unit_name_mangle_with_suffix(const char *name, enum unit_name_mangle allow_globs, const char *suffix);
-static inline char *unit_name_mangle(const char *name, enum unit_name_mangle allow_globs) {
-        return unit_name_mangle_with_suffix(name, allow_globs, ".service");
+int unit_name_mangle_with_suffix(const char *name, UnitNameMangle allow_globs, const char *suffix, char **ret);
+
+static inline int unit_name_mangle(const char *name, UnitNameMangle allow_globs, char **ret) {
+        return unit_name_mangle_with_suffix(name, allow_globs, ".service", ret);
 }
 
-int build_subslice(const char *slice, const char*name, char **subslice);
+int slice_build_subslice(const char *slice, const char*name, char **subslice);
+
+const char *unit_type_to_string(UnitType i) _const_;
+UnitType unit_type_from_string(const char *s) _pure_;
+
+const char *unit_load_state_to_string(UnitLoadState i) _const_;
+UnitLoadState unit_load_state_from_string(const char *s) _pure_;
 
 const char *unit_dependency_to_string(UnitDependency i) _const_;
 UnitDependency unit_dependency_from_string(const char *s) _pure_;
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index eb9737d577..4f36ba8dc3 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -1636,13 +1636,15 @@ static int list_dependencies(sd_bus *bus, char **args) {
         _cleanup_strv_free_ char **units = NULL;
         _cleanup_free_ char *unit = NULL;
         const char *u;
+        int r;
 
         assert(bus);
 
         if (args[1]) {
-                unit = unit_name_mangle(args[1], MANGLE_NOGLOB);
-                if (!unit)
-                        return log_oom();
+                r = unit_name_mangle(args[1], UNIT_NAME_NOGLOB, &unit);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to mangle unit name: %m");
+
                 u = unit;
         } else
                 u = SPECIAL_DEFAULT_TARGET;
@@ -1938,9 +1940,9 @@ static int set_default(sd_bus *bus, char **args) {
         unsigned n_changes = 0;
         int r;
 
-        unit = unit_name_mangle_with_suffix(args[1], MANGLE_NOGLOB, ".target");
-        if (!unit)
-                return log_oom();
+        r = unit_name_mangle_with_suffix(args[1], UNIT_NAME_NOGLOB, ".target", &unit);
+        if (r < 0)
+                return log_error_errno(r, "Failed to mangle unit name: %m");
 
         if (!bus || avoid_bus()) {
                 r = unit_file_set_default(arg_scope, arg_root, unit, true, &changes, &n_changes);
@@ -2257,7 +2259,7 @@ static int unit_find_paths(
         assert(fragment_path);
         assert(lp);
 
-        if (!avoid_bus_cache && !unit_name_is_template(unit_name)) {
+        if (!avoid_bus_cache && !unit_name_is_valid(unit_name, UNIT_NAME_TEMPLATE)) {
                 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
                 _cleanup_bus_message_unref_ sd_bus_message *unit_load_error = NULL;
                 _cleanup_free_ char *unit = NULL;
@@ -2323,24 +2325,23 @@ static int unit_find_paths(
 
                 names = set_new(NULL);
                 if (!names)
-                        return -ENOMEM;
+                        return log_oom();
 
                 r = set_put(names, unit_name);
                 if (r < 0)
-                        return r;
+                        return log_error_errno(r, "Failed to add unit name: %m");
 
                 r = unit_file_find_path(lp, unit_name, &path);
                 if (r < 0)
                         return r;
 
                 if (r == 0) {
-                        _cleanup_free_ char *template;
-
-                        template = unit_name_template(unit_name);
-                        if (!template)
-                                return log_oom();
+                        _cleanup_free_ char *template = NULL;
 
-                        if (!streq(template, unit_name)) {
+                        r = unit_name_template(unit_name, &template);
+                        if (r != -EINVAL)
+                                return log_error_errno(r, "Failed to determine template name: %m");
+                        if (r >= 0) {
                                 r = unit_file_find_path(lp, template, &path);
                                 if (r < 0)
                                         return r;
@@ -2382,9 +2383,9 @@ static int check_one_unit(sd_bus *bus, const char *name, const char *good_states
 
         assert(name);
 
-        n = unit_name_mangle(name, MANGLE_NOGLOB);
-        if (!n)
-                return log_oom();
+        r = unit_name_mangle(name, UNIT_NAME_NOGLOB, &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to mangle unit name: %m");
 
         /* We don't use unit_dbus_path_from_name() directly since we
          * don't want to load the unit if it isn't loaded. */
@@ -2439,9 +2440,9 @@ static int check_triggering_units(
         char **i;
         int r;
 
-        n = unit_name_mangle(name, MANGLE_NOGLOB);
-        if (!n)
-                return log_oom();
+        r = unit_name_mangle(name, UNIT_NAME_NOGLOB, &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to mangle unit name: %m");
 
         path = unit_dbus_path_from_name(n);
         if (!path)
@@ -2595,17 +2596,17 @@ static int expand_names(sd_bus *bus, char **names, const char* suffix, char ***r
 
         _cleanup_strv_free_ char **mangled = NULL, **globs = NULL;
         char **name;
-        int r = 0, i;
+        int r, i;
 
         STRV_FOREACH(name, names) {
                 char *t;
 
                 if (suffix)
-                        t = unit_name_mangle_with_suffix(*name, MANGLE_GLOB, suffix);
+                        r = unit_name_mangle_with_suffix(*name, UNIT_NAME_GLOB, suffix, &t);
                 else
-                        t = unit_name_mangle(*name, MANGLE_GLOB);
-                if (!t)
-                        return log_oom();
+                        r = unit_name_mangle(*name, UNIT_NAME_GLOB, &t);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to mangle name: %m");
 
                 if (string_is_glob(t))
                         r = strv_consume(&globs, t);
@@ -4673,9 +4674,9 @@ static int set_property(sd_bus *bus, char **args) {
         if (r < 0)
                 return bus_log_create_error(r);
 
-        n = unit_name_mangle(args[1], MANGLE_NOGLOB);
-        if (!n)
-                return log_oom();
+        r = unit_name_mangle(args[1], UNIT_NAME_NOGLOB, &n);
+        if (r < 0)
+                return log_error_errno(r, "Failed to mangle unit name: %m");
 
         r = sd_bus_message_append(m, "sb", n, arg_runtime);
         if (r < 0)
@@ -4721,12 +4722,15 @@ static int snapshot(sd_bus *bus, char **args) {
 
         polkit_agent_open_if_enabled();
 
-        if (strv_length(args) > 1)
-                n = unit_name_mangle_with_suffix(args[1], MANGLE_NOGLOB, ".snapshot");
-        else
+        if (strv_length(args) > 1) {
+                r = unit_name_mangle_with_suffix(args[1], UNIT_NAME_NOGLOB, ".snapshot", &n);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to generate unit name: %m");
+        } else {
                 n = strdup("");
-        if (!n)
-                return log_oom();
+                if (!n)
+                        return log_oom();
+        }
 
         r = sd_bus_call_method(
                         bus,
@@ -5217,25 +5221,29 @@ static int enable_sysv_units(const char *verb, char **args) {
 
 static int mangle_names(char **original_names, char ***mangled_names) {
         char **i, **l, **name;
+        int r;
 
-        l = new(char*, strv_length(original_names) + 1);
+        l = i = new(char*, strv_length(original_names) + 1);
         if (!l)
                 return log_oom();
 
-        i = l;
         STRV_FOREACH(name, original_names) {
 
                 /* When enabling units qualified path names are OK,
                  * too, hence allow them explicitly. */
 
-                if (is_path(*name))
+                if (is_path(*name)) {
                         *i = strdup(*name);
-                else
-                        *i = unit_name_mangle(*name, MANGLE_NOGLOB);
-
-                if (!*i) {
-                        strv_free(l);
-                        return log_oom();
+                        if (!*i) {
+                                strv_free(l);
+                                return log_oom();
+                        }
+                } else {
+                        r = unit_name_mangle(*name, UNIT_NAME_NOGLOB, i);
+                        if (r < 0) {
+                                strv_free(l);
+                                return log_error_errno(r, "Failed to mangle unit name: %m");
+                        }
                 }
 
                 i++;
@@ -5418,9 +5426,9 @@ static int add_dependency(sd_bus *bus, char **args) {
         if (!args[1])
                 return 0;
 
-        target = unit_name_mangle_with_suffix(args[1], MANGLE_NOGLOB, ".target");
-        if (!target)
-                return log_oom();
+        r = unit_name_mangle_with_suffix(args[1], UNIT_NAME_NOGLOB, ".target", &target);
+        if (r < 0)
+                return log_error_errno(r, "Failed to mangle unit name: %m");
 
         r = mangle_names(args+2, &names);
         if (r < 0)
diff --git a/src/sysv-generator/sysv-generator.c b/src/sysv-generator/sysv-generator.c
index 714ce8f6cb..0c839c2c53 100644
--- a/src/sysv-generator/sysv-generator.c
+++ b/src/sysv-generator/sysv-generator.c
@@ -310,11 +310,13 @@ static int sysv_translate_facility(const char *name, const char *filename, char
          * out whether something is a target or a service alias. */
 
         if (*name == '$') {
-                if (!unit_prefix_is_valid(n))
-                        return -EINVAL;
+                int k;
 
                 /* Facilities starting with $ are most likely targets */
-                r = unit_name_build(n, NULL, ".target");
+                k = unit_name_build(n, NULL, ".target", &r);
+                if (k < 0)
+                        return k;
+
         } else if (streq_ptr(n, filename))
                 /* Names equaling the file name of the services are redundant */
                 return 0;
diff --git a/src/test/test-unit-name.c b/src/test/test-unit-name.c
index 7d882aebd6..5e34f18e31 100644
--- a/src/test/test-unit-name.c
+++ b/src/test/test-unit-name.c
@@ -33,79 +33,156 @@
 #include "specifier.h"
 #include "util.h"
 #include "macro.h"
+#include "path-util.h"
 #include "test-helper.h"
 
-static void test_replacements(void) {
-#define expect(pattern, repl, expected)                            \
-        {                                                          \
-                _cleanup_free_ char *t =                           \
-                        unit_name_replace_instance(pattern, repl); \
-                puts(t);                                           \
-                assert_se(streq(t, expected));                        \
-        }
+static void test_unit_name_is_valid(void) {
+        assert_se(unit_name_is_valid("foo.service", UNIT_NAME_ANY));
+        assert_se(unit_name_is_valid("foo.service", UNIT_NAME_PLAIN));
+        assert_se(!unit_name_is_valid("foo.service", UNIT_NAME_INSTANCE));
+        assert_se(!unit_name_is_valid("foo.service", UNIT_NAME_TEMPLATE));
+        assert_se(!unit_name_is_valid("foo.service", UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE));
+
+        assert_se(unit_name_is_valid("foo@bar.service", UNIT_NAME_ANY));
+        assert_se(!unit_name_is_valid("foo@bar.service", UNIT_NAME_PLAIN));
+        assert_se(unit_name_is_valid("foo@bar.service", UNIT_NAME_INSTANCE));
+        assert_se(!unit_name_is_valid("foo@bar.service", UNIT_NAME_TEMPLATE));
+        assert_se(unit_name_is_valid("foo@bar.service", UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE));
+
+        assert_se(unit_name_is_valid("foo@.service", UNIT_NAME_ANY));
+        assert_se(!unit_name_is_valid("foo@.service", UNIT_NAME_PLAIN));
+        assert_se(!unit_name_is_valid("foo@.service", UNIT_NAME_INSTANCE));
+        assert_se(unit_name_is_valid("foo@.service", UNIT_NAME_TEMPLATE));
+        assert_se(unit_name_is_valid("foo@.service", UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE));
+
+        assert_se(!unit_name_is_valid(".service", UNIT_NAME_ANY));
+        assert_se(!unit_name_is_valid("", UNIT_NAME_ANY));
+        assert_se(!unit_name_is_valid("foo.waldo", UNIT_NAME_ANY));
+        assert_se(!unit_name_is_valid("@.service", UNIT_NAME_ANY));
+        assert_se(!unit_name_is_valid("@piep.service", UNIT_NAME_ANY));
+}
 
-        expect("foo@.service", "waldo", "foo@waldo.service");
-        expect("foo@xyz.service", "waldo", "foo@waldo.service");
-        expect("xyz", "waldo", "xyz");
-        expect("", "waldo", "");
-        expect("foo.service", "waldo", "foo.service");
-        expect(".service", "waldo", ".service");
-        expect("foo@", "waldo", "foo@waldo");
-        expect("@bar", "waldo", "@waldo");
+static void test_u_n_r_i_one(const char *pattern, const char *repl, const char *expected, int ret) {
+        _cleanup_free_ char *t = NULL;
+        assert_se(unit_name_replace_instance(pattern, repl, &t) == ret);
+        puts(strna(t));
+        assert_se(streq_ptr(t, expected));
+}
 
+static void test_u_n_r_i(void) {
         puts("-------------------------------------------------");
-#undef expect
-#define expect(path, suffix, expected)                             \
-        {                                                          \
-                _cleanup_free_ char *k, *t =                       \
-                        unit_name_from_path(path, suffix);         \
-                puts(t);                                           \
-                k = unit_name_to_path(t);                          \
-                puts(k);                                           \
-                assert_se(streq(k, expected ? expected : path));      \
-        }
+        test_u_n_r_i_one("foo@.service", "waldo", "foo@waldo.service", 0);
+        test_u_n_r_i_one("foo@xyz.service", "waldo", "foo@waldo.service", 0);
+        test_u_n_r_i_one("xyz", "waldo", NULL, -EINVAL);
+        test_u_n_r_i_one("", "waldo", NULL, -EINVAL);
+        test_u_n_r_i_one("foo.service", "waldo", NULL, -EINVAL);
+        test_u_n_r_i_one(".service", "waldo", NULL, -EINVAL);
+        test_u_n_r_i_one("foo@", "waldo", NULL, -EINVAL);
+        test_u_n_r_i_one("@bar", "waldo", NULL, -EINVAL);
+}
 
-        expect("/waldo", ".mount", NULL);
-        expect("/waldo/quuix", ".mount", NULL);
-        expect("/waldo/quuix/", ".mount", "/waldo/quuix");
-        expect("/", ".mount", NULL);
-        expect("///", ".mount", "/");
+static void test_u_n_f_p_one(const char *path, const char *suffix, const char *expected, int ret) {
+        _cleanup_free_ char *t = NULL;
 
-        puts("-------------------------------------------------");
-#undef expect
-#define expect(pattern, path, suffix, expected)                              \
-        {                                                                    \
-                _cleanup_free_ char *t =                                     \
-                        unit_name_from_path_instance(pattern, path, suffix); \
-                puts(t);                                                     \
-                assert_se(streq(t, expected));                                  \
-        }
+        assert_se(unit_name_from_path(path, suffix, &t) == ret);
+        puts(strna(t));
+        assert_se(streq_ptr(t, expected));
 
-        expect("waldo", "/waldo", ".mount", "waldo@waldo.mount");
-        expect("waldo", "/waldo////quuix////", ".mount", "waldo@waldo-quuix.mount");
-        expect("waldo", "/", ".mount", "waldo@-.mount");
-        expect("wa--ldo", "/--", ".mount", "wa--ldo@\\x2d\\x2d.mount");
+        if (t) {
+                _cleanup_free_ char *k = NULL;
+                assert_se(unit_name_to_path(t, &k) == 0);
+                puts(strna(k));
+                assert_se(path_equal(k, isempty(path) ? "/" : path));
+        }
+}
 
+static void test_u_n_f_p(void) {
         puts("-------------------------------------------------");
-#undef expect
-#define expect(pattern)                                                     \
-        {                                                                   \
-                _cleanup_free_ char *k, *t;                                 \
-                assert_se(t = unit_name_mangle(pattern, MANGLE_NOGLOB));    \
-                assert_se(k = unit_name_mangle(t, MANGLE_NOGLOB));          \
-                puts(t);                                                    \
-                assert_se(streq(t, k));                                     \
+        test_u_n_f_p_one("/waldo", ".mount", "waldo.mount", 0);
+        test_u_n_f_p_one("/waldo/quuix", ".mount", "waldo-quuix.mount", 0);
+        test_u_n_f_p_one("/waldo/quuix/", ".mount", "waldo-quuix.mount", 0);
+        test_u_n_f_p_one("", ".mount", "-.mount", 0);
+        test_u_n_f_p_one("/", ".mount", "-.mount", 0);
+        test_u_n_f_p_one("///", ".mount", "-.mount", 0);
+        test_u_n_f_p_one("/foo/../bar", ".mount", NULL, -EINVAL);
+        test_u_n_f_p_one("/foo/./bar", ".mount", NULL, -EINVAL);
+}
+
+static void test_u_n_f_p_i_one(const char *pattern, const char *path, const char *suffix, const char *expected, int ret) {
+        _cleanup_free_ char *t = NULL;
+
+        assert_se(unit_name_from_path_instance(pattern, path, suffix, &t) == ret);
+        puts(strna(t));
+        assert_se(streq_ptr(t, expected));
+
+        if (t) {
+                _cleanup_free_ char *k = NULL, *v = NULL;
+
+                assert_se(unit_name_to_instance(t, &k) > 0);
+                assert_se(unit_name_path_unescape(k, &v) == 0);
+                assert_se(path_equal(v, isempty(path) ? "/" : path));
         }
+}
 
-        expect("/home");
-        expect("/dev/sda");
-        expect("üxknürz.service");
-        expect("foobar-meh...waldi.service");
-        expect("_____####----.....service");
-        expect("_____##@;;;,,,##----.....service");
-        expect("xxx@@@@/////\\\\\\\\\\yyy.service");
+static void test_u_n_f_p_i(void) {
+        puts("-------------------------------------------------");
 
-#undef expect
+        test_u_n_f_p_i_one("waldo", "/waldo", ".mount", "waldo@waldo.mount", 0);
+        test_u_n_f_p_i_one("waldo", "/waldo////quuix////", ".mount", "waldo@waldo-quuix.mount", 0);
+        test_u_n_f_p_i_one("waldo", "/", ".mount", "waldo@-.mount", 0);
+        test_u_n_f_p_i_one("waldo", "", ".mount", "waldo@-.mount", 0);
+        test_u_n_f_p_i_one("waldo", "///", ".mount", "waldo@-.mount", 0);
+        test_u_n_f_p_i_one("waldo", "..", ".mount", NULL, -EINVAL);
+        test_u_n_f_p_i_one("waldo", "/foo", ".waldi", NULL, -EINVAL);
+        test_u_n_f_p_i_one("wa--ldo", "/--", ".mount", "wa--ldo@\\x2d\\x2d.mount", 0);
+}
+
+static void test_u_n_t_p_one(const char *unit, const char *path, int ret) {
+        _cleanup_free_ char *p = NULL;
+
+        assert_se(unit_name_to_path(unit, &p) == ret);
+        assert_se(streq_ptr(path, p));
+}
+
+static void test_u_n_t_p(void) {
+        test_u_n_t_p_one("home.mount", "/home", 0);
+        test_u_n_t_p_one("home-lennart.mount", "/home/lennart", 0);
+        test_u_n_t_p_one("home-lennart-.mount", NULL, -EINVAL);
+        test_u_n_t_p_one("-home-lennart.mount", NULL, -EINVAL);
+        test_u_n_t_p_one("-home--lennart.mount", NULL, -EINVAL);
+        test_u_n_t_p_one("home-..-lennart.mount", NULL, -EINVAL);
+        test_u_n_t_p_one("", NULL, -EINVAL);
+        test_u_n_t_p_one("home/foo", NULL, -EINVAL);
+}
+
+static void test_u_n_m_one(const char *pattern, const char *expect, int ret) {
+        _cleanup_free_ char *t = NULL;
+
+        assert_se(unit_name_mangle(pattern, UNIT_NAME_NOGLOB, &t) == ret);
+        puts(strna(t));
+        assert_se(streq_ptr(t, expect));
+
+        if (t) {
+                _cleanup_free_ char *k = NULL;
+
+                assert_se(unit_name_is_valid(t, UNIT_NAME_ANY));
+
+                assert_se(unit_name_mangle(t, UNIT_NAME_NOGLOB, &k) == 0);
+                assert_se(streq_ptr(t, k));
+        }
+}
+
+static void test_u_n_m(void) {
+        puts("-------------------------------------------------");
+        test_u_n_m_one("foo.service", "foo.service", 0);
+        test_u_n_m_one("/home", "home.mount", 1);
+        test_u_n_m_one("/dev/sda", "dev-sda.device", 1);
+        test_u_n_m_one("üxknürz.service", "\\xc3\\xbcxkn\\xc3\\xbcrz.service", 1);
+        test_u_n_m_one("foobar-meh...waldi.service", "foobar-meh...waldi.service", 0);
+        test_u_n_m_one("_____####----.....service", "_____\\x23\\x23\\x23\\x23----.....service", 1);
+        test_u_n_m_one("_____##@;;;,,,##----.....service", "_____\\x23\\x23@\\x3b\\x3b\\x3b\\x2c\\x2c\\x2c\\x23\\x23----.....service", 1);
+        test_u_n_m_one("xxx@@@@/////\\\\\\\\\\yyy.service", "xxx@@@@-----\\\\\\\\\\yyy.service", 1);
+        test_u_n_m_one("", NULL, -EINVAL);
 }
 
 static int test_unit_printf(void) {
@@ -224,64 +301,49 @@ static void test_unit_prefix_is_valid(void) {
 }
 
 static void test_unit_name_change_suffix(void) {
-        char *r;
+        char *t;
 
-        r = unit_name_change_suffix("foo.bar", ".service");
-        assert_se(r);
-        assert_se(streq(r, "foo.service"));
-        free(r);
+        assert_se(unit_name_change_suffix("foo.mount", ".service", &t) == 0);
+        assert_se(streq(t, "foo.service"));
+        free(t);
 
-        r = unit_name_change_suffix("foo@stuff.bar", ".boo");
-        assert_se(r);
-        assert_se(streq(r, "foo@stuff.boo"));
-        free(r);
+        assert_se(unit_name_change_suffix("foo@stuff.service", ".socket", &t) == 0);
+        assert_se(streq(t, "foo@stuff.socket"));
+        free(t);
 }
 
 static void test_unit_name_build(void) {
-        char *r;
-
-        r = unit_name_build("foo", "bar", ".service");
-        assert_se(r);
-        assert_se(streq(r, "foo@bar.service"));
-        free(r);
+        char *t;
 
-        r = unit_name_build("fo0-stUff_b", "bar", ".mount");
-        assert_se(r);
-        assert_se(streq(r, "fo0-stUff_b@bar.mount"));
-        free(r);
-
-        r = unit_name_build("foo", NULL, ".service");
-        assert_se(r);
-        assert_se(streq(r, "foo.service"));
-        free(r);
-}
+        assert_se(unit_name_build("foo", "bar", ".service", &t) == 0);
+        assert_se(streq(t, "foo@bar.service"));
+        free(t);
 
-static void test_unit_name_is_instance(void) {
-        assert_se(unit_name_is_instance("a@b.service"));
-        assert_se(unit_name_is_instance("a-c_c01Aj@b05Dii_-oioi.service"));
+        assert_se(unit_name_build("fo0-stUff_b", "bar", ".mount", &t) == 0);
+        assert_se(streq(t, "fo0-stUff_b@bar.mount"));
+        free(t);
 
-        assert_se(!unit_name_is_instance("a.service"));
-        assert_se(!unit_name_is_instance("a@.service"));
-        assert_se(!unit_name_is_instance("junk"));
-        assert_se(!unit_name_is_instance(""));
+        assert_se(unit_name_build("foo", NULL, ".service", &t) == 0);
+        assert_se(streq(t, "foo.service"));
+        free(t);
 }
 
 static void test_build_subslice(void) {
         char *a;
         char *b;
 
-        assert_se(build_subslice("-.slice", "foo", &a) >= 0);
-        assert_se(build_subslice(a, "bar", &b) >= 0);
+        assert_se(slice_build_subslice("-.slice", "foo", &a) >= 0);
+        assert_se(slice_build_subslice(a, "bar", &b) >= 0);
         free(a);
-        assert_se(build_subslice(b, "barfoo", &a) >= 0);
+        assert_se(slice_build_subslice(b, "barfoo", &a) >= 0);
         free(b);
-        assert_se(build_subslice(a, "foobar", &b) >= 0);
+        assert_se(slice_build_subslice(a, "foobar", &b) >= 0);
         free(a);
         assert_se(streq(b, "foo-bar-barfoo-foobar.slice"));
         free(b);
 
-        assert_se(build_subslice("foo.service", "bar", &a) < 0);
-        assert_se(build_subslice("foo", "bar", &a) < 0);
+        assert_se(slice_build_subslice("foo.service", "bar", &a) < 0);
+        assert_se(slice_build_subslice("foo", "bar", &a) < 0);
 }
 
 static void test_unit_name_to_instance(void) {
@@ -298,13 +360,13 @@ static void test_unit_name_to_instance(void) {
         assert_se(streq(instance, ""));
         free(instance);
 
-        r = unit_name_to_instance("fo0-stUff_b@b.e", &instance);
+        r = unit_name_to_instance("fo0-stUff_b@b.service", &instance);
         assert_se(r >= 0);
         assert_se(streq(instance, "b"));
         free(instance);
 
-        r = unit_name_to_instance("foo.bar", &instance);
-        assert_se(r >= 0);
+        r = unit_name_to_instance("foo.service", &instance);
+        assert_se(r == 0);
         assert_se(!instance);
 
         r = unit_name_to_instance("fooj@unk", &instance);
@@ -322,43 +384,37 @@ static void test_unit_name_escape(void) {
         assert_se(streq(r, "ab\\x2b\\x2dc.a-bc\\x40foo.service"));
 }
 
-static void test_unit_name_template(void) {
-#define expect(name, expected) \
-        { \
-                _cleanup_free_ char *f = NULL; \
-                f = unit_name_template(name); \
-                assert_se(f); \
-                printf("got: %s, expected: %s\n", f, expected); \
-                assert_se(streq(f, expected)); \
-        }
-        expect("foo@bar.service", "foo@.service")
-        expect("foo.mount", "foo.mount")
-#undef expect
-}
 
-static void test_unit_name_is_template(void) {
-        assert_se(unit_name_is_template("foo@.service"));
-        assert_se(unit_name_is_template("bar@.path"));
+static void test_u_n_t_one(const char *name, const char *expected, int ret) {
+        _cleanup_free_ char *f = NULL;
 
-        assert_se(!unit_name_is_template("bar@i.mount"));
-        assert_se(!unit_name_is_template("bar@foobbbb.service"));
-        assert_se(!unit_name_is_template("barfoo.service"));
+        assert_se(unit_name_template(name, &f) == ret);
+        printf("got: %s, expected: %s\n", strna(f), strna(expected));
+        assert_se(streq_ptr(f, expected));
+}
+
+static void test_unit_name_template(void) {
+        test_u_n_t_one("foo@bar.service", "foo@.service", 0);
+        test_u_n_t_one("foo.mount", NULL, -EINVAL);
 }
 
 int main(int argc, char* argv[]) {
         int rc = 0;
-        test_replacements();
+        test_unit_name_is_valid();
+        test_u_n_r_i();
+        test_u_n_f_p();
+        test_u_n_f_p_i();
+        test_u_n_m();
+        test_u_n_t_p();
         TEST_REQ_RUNNING_SYSTEMD(rc = test_unit_printf());
         test_unit_instance_is_valid();
         test_unit_prefix_is_valid();
         test_unit_name_change_suffix();
         test_unit_name_build();
-        test_unit_name_is_instance();
         test_build_subslice();
         test_unit_name_to_instance();
         test_unit_name_escape();
         test_unit_name_template();
-        test_unit_name_is_template();
 
         return rc;
 }