Allow symlinks to photos outside photos_dir, if enabled in config.php

src/classes/File.php

@@ -179,6 +179,10 @@ public static function a2r($file,$dir=NULL){
 
 		if($rf==$rd) return "";
 
+		if(Settings::$allow_symlinks_outside_photos_dir && substr($rf,0,strlen($rd)) != $rd && is_file($rf) ){
+            return substr($file,strlen($dir) + 1 );
+        }
+
 		if( substr($rf,0,strlen($rd)) != $rd ){
 			throw new Exception("This file is not inside the photos folder !<br/>");
 		}

src/classes/Menu.php

@@ -221,7 +221,8 @@ public static function list_files($dir,$rec = false, $hidden = false, $stopatfir
 
 			/// Content isn't hidden and is a file
 			if($content[0] != '.' || $hidden){
-				if(is_file($path=$dir."/".$content)){
+                $path = $dir."/".$content;
+				if(is_file($path) || is_link($path)){
 					if((File::Type($path) && (File::Type($path) == "Image" || File::Type($path)=="Video")) || $all_file_type){
 						/// Add content to list
 						$list[]=$path;

src/classes/Settings.php

@@ -66,6 +66,9 @@ class Settings extends Page
 	/// Quality of mini thumbnails in overview, scala: 0-100
 	static public $quality_mini = 90;
 
+    /// The user can enable this to allow symlinks in his photos_dir to point to files outside his photos_dir
+    static public $allow_symlinks_outside_photos_dir = false;
+
 
 	/**** Admin Settings ****/
 
@@ -201,6 +204,10 @@ static public function init($forced = false, $config_file = NULL){
 		Settings::$conf_dir		=	$config->ps_generated."/Conf/";
 		Settings::$admin_settings_file = $config->ps_generated."/Conf/admin_settings.ini";
 
+        if (isset($config->allow_symlinks_outside_photos_dir)) {
+            Settings::$allow_symlinks_outside_photos_dir = (bool) $config->allow_symlinks_outside_photos_dir;
+        }
+
         if (isset($config->cache_max_age)) {
             Settings::$cache_max_age = (int) $config->cache_max_age;
 		}