by gisle: Fixed disabled themes showing up as eligible.

README.txt

@@ -86,6 +86,18 @@ Note that customerror keeps track of what page the user is trying to
 access, so after logging in, the user will be redirected to that page.
 
 
+Theme to be used on the error page
+----------------------------------
+
+If you've set an administration theme, the default is to use this on
+all pages where the path is "admin", including 403 and 404 error
+pages.  You can overide this by specifying a theme for custom error
+different from "System default".
+
+This setting has no effect if the administration theme is set to
+"<System default>".
+
+
 Custom redirects for 404 errors
 -------------------------------
 

customerror.module

@@ -74,7 +74,9 @@ function customerror_admin_settings() {
   ksort($themes);
   $theme_options[0] = t('System default');
   foreach ($themes as $theme) {
-    $theme_options[$theme->name] = $theme->name;
+    if ($theme->status) {
+      $theme_options[$theme->name] = $theme->name;
+    }
   }
 
   $errors = _customerror_enum_errors();
@@ -116,8 +118,8 @@ function customerror_admin_settings() {
       '#type' => 'select',
       '#options' => $theme_options,
       '#title' => t('Theme'),
-      '#description' => t('Theme to be used on the error page.'),
-      '#default_value' => customerror_get_theme($code),
+      '#description' => t('Theme to be used on the error page below the admin path.'),
+      '#default_value' => variable_get('customerror_' . $code . '_theme', 0),
     );
     $form[$group]['customerror_' . $code . '_php'] = array(
       '#type'          => 'checkbox',
@@ -129,7 +131,7 @@ function customerror_admin_settings() {
 
   $form['redirects'] = array(
     '#type'            => 'fieldset',
-    '#title'           => t('Redirects'),
+    '#title'           => t('404 Redirects'),
     '#collapsed'       => TRUE,
     '#collapsible'     => TRUE,
   );
@@ -279,10 +281,11 @@ function customerror_check_redirect() {
     return;
   }
 
-  $redirect_list = explode("\n", variable_get('customerror_redirect', ''));
-  if (empty($redirect_list)) {
+  $redirects = trim(variable_get('customerror_redirect', ''));
+  if (empty($redirects)) {
     return;
   }
+  $redirect_list = explode("\n", $redirects);
 
   foreach ($redirect_list as $item) {
     list($src, $dst) = explode(' ', $item);