user-accounts: prevent the only admin from being deleted or disabled

https://bugzilla.gnome.org/show_bug.cgi?id=690246

panels/user-accounts/um-password-dialog.c

@@ -644,7 +644,8 @@ visible_func (GtkTreeModel     *model,
                  * as this can lead to them being 'locked out'.
                  */
                 if (mode == UM_PASSWORD_DIALOG_MODE_LOCK_ACCOUNT &&
-                    (locked || act_user_get_uid (um->user) == getuid ()))
+                    (locked || act_user_get_uid (um->user) == getuid ()
+                     || would_demote_only_admin (um->user)))
                         return FALSE;
 
                 if (mode == UM_PASSWORD_DIALOG_MODE_UNLOCK_ACCOUNT && !locked)

panels/user-accounts/um-user-panel.c

@@ -1043,42 +1043,6 @@ remove_unlock_tooltip (GtkWidget *button)
                                               G_CALLBACK (show_tooltip_now), NULL);
 }
 
-static guint
-get_num_admin (ActUserManager *um)
-{
-        GSList *list;
-        GSList *l;
-        guint num_admin = 0;
-
-        list = act_user_manager_list_users (um);
-        for (l = list; l != NULL; l = l->next) {
-                ActUser *u = l->data;
-                if (act_user_get_account_type (u) == ACT_USER_ACCOUNT_TYPE_ADMINISTRATOR) {
-                        num_admin++;
-                }
-        }
-        g_slist_free (list);
-
-        return num_admin;
-}
-
-static gboolean
-would_demote_only_admin (ActUser        *user,
-                         ActUserManager *um)
-{
-        /* Prevent the user from demoting the only admin account.
-         * Returns TRUE when user is an administrator and there is only
-         * one administrator */
-
-        if (act_user_get_account_type (user) == ACT_USER_ACCOUNT_TYPE_STANDARD)
-                return FALSE;
-
-        if (get_num_admin (um) > 1)
-                return FALSE;
-
-        return TRUE;
-}
-
 static void
 on_permission_changed (GPermission *permission,
                        GParamSpec  *pspec,
@@ -1119,7 +1083,8 @@ on_permission_changed (GPermission *permission,
         }
 
         widget = get_widget (d, "remove-user-toolbutton");
-        gtk_widget_set_sensitive (widget, is_authorized && !self_selected);
+        gtk_widget_set_sensitive (widget, is_authorized && !self_selected
+                                  && !would_demote_only_admin (user));
         if (is_authorized) {
                 setup_tooltip_with_embedded_icon (widget, _("Delete the selected user account"), NULL, NULL);
         }
@@ -1146,7 +1111,7 @@ on_permission_changed (GPermission *permission,
                 remove_unlock_tooltip (get_widget (d, "autologin-switch"));
 
         } else if (is_authorized && act_user_is_local_account (user)) {
-                if (would_demote_only_admin (user, d->um)) {
+                if (would_demote_only_admin (user)) {
                         um_editable_combo_set_editable (UM_EDITABLE_COMBO (get_widget (d, "account-type-combo")), FALSE);
                 } else {
                         um_editable_combo_set_editable (UM_EDITABLE_COMBO (get_widget (d, "account-type-combo")), TRUE);
@@ -1158,7 +1123,7 @@ on_permission_changed (GPermission *permission,
         }
         else {
                 um_editable_combo_set_editable (UM_EDITABLE_COMBO (get_widget (d, "account-type-combo")), FALSE);
-                if (would_demote_only_admin (user, d->um)) {
+                if (would_demote_only_admin (user)) {
                         remove_unlock_tooltip (get_widget (d, "account-type-combo"));
                 } else {
                         add_unlock_tooltip (get_widget (d, "account-type-combo"));

panels/user-accounts/um-utils.c

@@ -1034,3 +1034,41 @@ set_user_icon_data (ActUser   *user,
 
         g_free (path);
 }
+
+static guint
+get_num_admin (ActUserManager *um)
+{
+        GSList *list;
+        GSList *l;
+        guint num_admin = 0;
+
+        list = act_user_manager_list_users (um);
+        for (l = list; l != NULL; l = l->next) {
+                ActUser *u = l->data;
+                if (act_user_get_account_type (u) == ACT_USER_ACCOUNT_TYPE_ADMINISTRATOR) {
+                        num_admin++;
+                }
+        }
+        g_slist_free (list);
+
+        return num_admin;
+}
+
+gboolean
+would_demote_only_admin (ActUser *user)
+{
+
+        ActUserManager *um = act_user_manager_get_default ();
+
+        /* Prevent the user from demoting the only admin account.
+         * Returns TRUE when user is an administrator and there is only
+         * one administrator */
+
+        if (act_user_get_account_type (user) == ACT_USER_ACCOUNT_TYPE_STANDARD)
+                return FALSE;
+
+        if (get_num_admin (um) > 1)
+                return FALSE;
+
+        return TRUE;
+}

panels/user-accounts/um-utils.h

@@ -81,6 +81,8 @@ GdkPixbuf * render_user_icon              (ActUser         *user,
 void     set_user_icon_data               (ActUser         *user,
                                            GdkPixbuf       *pixbuf);
 
+gboolean would_demote_only_admin          (ActUser *user);
+
 G_END_DECLS
 
 #endif