+static void warn_unit_file_changed(const char *name) {
+ log_warning("%sWarning:%s %s changed on disk. Run 'systemctl%s daemon-reload' to reload units.",
+ ansi_highlight_red(),
+ ansi_highlight_off(),
+ name,
+ arg_scope == UNIT_FILE_SYSTEM ? "" : " --user");
+}
+
+static int unit_file_find_path(LookupPaths *lp, const char *unit_name, char **unit_path) {
+ char **p;
+
+ assert(lp);
+ assert(unit_name);
+ assert(unit_path);
+
+ STRV_FOREACH(p, lp->unit_path) {
+ _cleanup_free_ char *path;
+
+ path = path_join(arg_root, *p, unit_name);
+ if (!path)
+ return log_oom();
+
+ if (access(path, F_OK) == 0) {
+ *unit_path = path;
+ path = NULL;
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int unit_find_paths(sd_bus *bus,
+ const char *unit_name,
+ bool avoid_bus_cache,
+ LookupPaths *lp,
+ char **fragment_path,
+ char ***dropin_paths) {
+ int r;
+
+ /**
+ * Finds where the unit is defined on disk. Returns 0 if the unit
+ * is not found. Returns 1 if it is found, and sets
+ * - the path to the unit in *path, if it exists on disk,
+ * - and a strv of existing drop-ins in *dropins,
+ * if the arg is not NULL and any dropins were found.
+ */
+
+ assert(unit_name);
+ assert(fragment_path);
+ assert(lp);
+
+ if (!avoid_bus_cache && !unit_name_is_template(unit_name)) {
+ _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+ _cleanup_free_ char *unit = NULL;
+ _cleanup_free_ char *path = NULL;
+ _cleanup_strv_free_ char **dropins = NULL;
+
+ unit = unit_dbus_path_from_name(unit_name);
+ if (!unit)
+ return log_oom();
+
+ if (need_daemon_reload(bus, unit_name) > 0)
+ warn_unit_file_changed(unit_name);
+
+ r = sd_bus_get_property_string(
+ bus,
+ "org.freedesktop.systemd1",
+ unit,
+ "org.freedesktop.systemd1.Unit",
+ "FragmentPath",
+ &error,
+ &path);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get FragmentPath: %s", bus_error_message(&error, r));
+
+ r = sd_bus_get_property_strv(
+ bus,
+ "org.freedesktop.systemd1",
+ unit,
+ "org.freedesktop.systemd1.Unit",
+ "DropInPaths",
+ &error,
+ &dropins);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get DropInPaths: %s", bus_error_message(&error, r));
+
+ r = 0;
+ if (!isempty(path)) {
+ *fragment_path = path;
+ path = NULL;
+ r = 1;
+ }
+
+ if (dropin_paths && !strv_isempty(dropins)) {
+ *dropin_paths = dropins;
+ dropins = NULL;
+ r = 1;
+ }
+ } else {
+ _cleanup_set_free_ Set *names;
+
+ names = set_new(NULL);
+ if (!names)
+ return -ENOMEM;
+
+ r = set_put(names, unit_name);
+ if (r < 0)
+ return r;
+
+ r = unit_file_find_path(lp, unit_name, fragment_path);
+ if (r < 0)
+ return r;
+
+ if (r == 0) {
+ _cleanup_free_ char *template;
+
+ template = unit_name_template(unit_name);
+ if (!template)
+ return log_oom();
+
+ if (!streq(template, unit_name)) {
+ r = unit_file_find_path(lp, template, fragment_path);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ if (dropin_paths)
+ r = unit_file_find_dropin_paths(lp->unit_path, NULL, names, dropin_paths);
+ }
+
+ return r;
+}
+