let files go to SSL dir too

README

@@ -1462,6 +1462,8 @@ server: server name to use when creating URLs for uploaded files.
         a virtual server here can speed up Web performance.
 path: URL path, relative to the server, to find files. Defaults to
       main path + '/file/'.
+ssl: whether to use HTTPS for file URLs. Defaults to null, meaning to
+     guess based on other SSL settings.
 filecommand: command to use for determining the type of a file. May be
              skipped if fileinfo extension is installed. Defaults to
              '/usr/bin/file'.

classes/File.php

@@ -228,9 +228,20 @@ class File extends Memcached_DataObject
                 $server = common_config('site', 'server');
             }
 
-            // XXX: protocol
+            $ssl = common_config('attachments', 'ssl');
 
-            return 'http://'.$server.$path.$filename;
+            if (is_null($ssl)) { // null -> guess
+                if (common_config('site', 'ssl') == 'always' &&
+                    !common_config('attachments', 'server')) {
+                    $ssl = true;
+                } else {
+                    $ssl = false;
+                }
+            }
+
+            $protocol = ($ssl) ? 'https' : 'http';
+
+            return $protocol.'://'.$server.$path.$filename;
         }
     }
 

lib/default.php

@@ -188,6 +188,7 @@ $default =
         array('server' => null,
               'dir' => INSTALLDIR . '/file/',
               'path' => $_path . '/file/',
+              'ssl' => null,
               'supported' => array('image/png',
                                    'image/jpeg',
                                    'image/gif',