+int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
+ Unit *found;
+ char *t;
+
+ assert(u);
+ assert(type);
+ assert(_found);
+
+ if (!(t = unit_name_change_suffix(u->meta.id, type)))
+ return -ENOMEM;
+
+ assert(!unit_has_name(u, t));
+
+ found = manager_get_unit(u->meta.manager, t);
+ free(t);
+
+ if (!found)
+ return -ENOENT;
+
+ *_found = found;
+ return 0;
+}
+
+static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
+ Unit *u = userdata;
+ assert(u);
+
+ return unit_name_to_prefix_and_instance(u->meta.id);
+}
+
+static char *specifier_prefix(char specifier, void *data, void *userdata) {
+ Unit *u = userdata;
+ assert(u);
+
+ return unit_name_to_prefix(u->meta.id);
+}
+
+static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
+ Unit *u = userdata;
+ char *p, *r;
+
+ assert(u);
+
+ if (!(p = unit_name_to_prefix(u->meta.id)))
+ return NULL;
+
+ r = unit_name_unescape(p);
+ free(p);
+
+ return r;
+}
+
+static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
+ Unit *u = userdata;
+ assert(u);
+
+ if (u->meta.instance)
+ return unit_name_unescape(u->meta.instance);
+
+ return strdup("");
+}
+
+char *unit_name_printf(Unit *u, const char* format) {
+
+ /*
+ * This will use the passed string as format string and
+ * replace the following specifiers:
+ *
+ * %n: the full id of the unit (foo@bar.waldo)
+ * %N: the id of the unit without the suffix (foo@bar)
+ * %p: the prefix (foo)
+ * %i: the instance (bar)
+ */
+
+ const Specifier table[] = {
+ { 'n', specifier_string, u->meta.id },
+ { 'N', specifier_prefix_and_instance, NULL },
+ { 'p', specifier_prefix, NULL },
+ { 'i', specifier_string, u->meta.instance },
+ { 0, NULL, NULL }
+ };
+
+ assert(u);
+ assert(format);
+
+ return specifier_printf(format, table, u);
+}
+
+char *unit_full_printf(Unit *u, const char *format) {
+
+ /* This is similar to unit_name_printf() but also supports
+ * unescaping */
+
+ const Specifier table[] = {
+ { 'n', specifier_string, u->meta.id },
+ { 'N', specifier_prefix_and_instance, NULL },
+ { 'p', specifier_prefix, NULL },
+ { 'P', specifier_prefix_unescaped, NULL },
+ { 'i', specifier_string, u->meta.instance },
+ { 'I', specifier_instance_unescaped, NULL },
+ { 0, NULL, NULL }
+ };
+
+ assert(u);
+ assert(format);
+
+ return specifier_printf(format, table, u);
+}
+
+char **unit_full_printf_strv(Unit *u, char **l) {
+ size_t n;
+ char **r, **i, **j;
+
+ /* Applies unit_full_printf to every entry in l */
+
+ assert(u);
+
+ n = strv_length(l);
+ if (!(r = new(char*, n+1)))
+ return NULL;
+
+ for (i = l, j = r; *i; i++, j++)
+ if (!(*j = unit_full_printf(u, *i)))
+ goto fail;
+
+ *j = NULL;
+ return r;
+
+fail:
+ j--;
+ while (j >= r)
+ free(*j);
+
+ free(r);
+
+ return NULL;
+}
+
+int unit_watch_bus_name(Unit *u, const char *name) {
+ assert(u);
+ assert(name);
+
+ /* Watch a specific name on the bus. We only support one unit
+ * watching each name for now. */
+
+ return hashmap_put(u->meta.manager->watch_bus, name, u);
+}
+
+void unit_unwatch_bus_name(Unit *u, const char *name) {
+ assert(u);
+ assert(name);
+
+ hashmap_remove_value(u->meta.manager->watch_bus, name, u);
+}
+
+bool unit_can_serialize(Unit *u) {
+ assert(u);
+
+ return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
+}
+
+int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
+ int r;
+
+ assert(u);
+ assert(f);
+ assert(fds);
+
+ if (!unit_can_serialize(u))
+ return 0;
+
+ if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
+ return r;
+
+ /* End marker */
+ fputc('\n', f);
+ return 0;
+}
+
+void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
+ va_list ap;
+
+ assert(u);
+ assert(f);
+ assert(key);
+ assert(format);
+
+ fputs(key, f);
+ fputc('=', f);
+
+ va_start(ap, format);
+ vfprintf(f, format, ap);
+ va_end(ap);
+
+ fputc('\n', f);
+}
+
+void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
+ assert(u);
+ assert(f);
+ assert(key);
+ assert(value);
+
+ fprintf(f, "%s=%s\n", key, value);
+}
+
+int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
+ int r;
+
+ assert(u);
+ assert(f);
+ assert(fds);
+
+ if (!unit_can_serialize(u))
+ return 0;
+
+ for (;;) {
+ char line[1024], *l, *v;
+ size_t k;
+
+ if (!fgets(line, sizeof(line), f)) {
+ if (feof(f))
+ return 0;
+ return -errno;
+ }
+
+ l = strstrip(line);
+
+ /* End marker */
+ if (l[0] == 0)
+ return 0;
+
+ k = strcspn(l, "=");
+
+ if (l[k] == '=') {
+ l[k] = 0;
+ v = l+k+1;
+ } else
+ v = l+k;
+
+ if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
+ return r;
+ }
+}
+
+int unit_add_node_link(Unit *u, const char *what, bool wants) {
+ Unit *device;
+ char *e;
+ int r;
+
+ assert(u);
+
+ if (!what)
+ return 0;
+
+ /* Adds in links to the device node that this unit is based on */
+
+ if (!path_startswith(what, "/dev/") && !path_startswith(what, "/sys/"))
+ return 0;
+
+ if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
+ return -ENOMEM;
+
+ r = manager_load_unit(u->meta.manager, e, NULL, &device);
+ free(e);
+
+ if (r < 0)
+ return r;
+
+ if ((r = unit_add_dependency(u, UNIT_AFTER, device, true)) < 0)
+ return r;
+
+ if ((r = unit_add_dependency(u, UNIT_REQUIRES, device, true)) < 0)
+ return r;
+
+ if (wants)
+ if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
+ return r;
+
+ return 0;
+}
+