request.php: add type check to the not empty check of a string

The not equal comparison (<>) of a variable with an empty string
could lead to false positive results as the compare do not check
the type and thereby could not make sure that the checked variable
is a string. The usage of the not identical comparison operator
(!==) make sure that the variable is a string and not empty.

diff --git a/lib/request.php b/lib/request.php
index 859276a12a3de34436950403c8e25ba627278fc6..4d8380eb9ac49b85d1676fd057d18613d374e816 100755 (executable)
--- a/lib/request.php
+++ b/lib/request.php
@@ -14,7 +14,7 @@ class OC_Request {
        private static function isOverwriteCondition($type = '') {
                $regex = '/' . OC_Config::getValue('overwritecondaddr', '')  . '/';
                return $regex === '//' or preg_match($regex, $_SERVER['REMOTE_ADDR']) === 1
-                       or ($type <> 'protocol' and OC_Config::getValue('forcessl', false));
+                       or ($type !== 'protocol' and OC_Config::getValue('forcessl', false));
        }
 
        /**
@@ -28,7 +28,7 @@ class OC_Request {
                if(OC::$CLI) {
                        return 'localhost';
                }
-               if(OC_Config::getValue('overwritehost', '')<>'' and self::isOverwriteCondition()) {
+               if(OC_Config::getValue('overwritehost', '') !== '' and self::isOverwriteCondition()) {
                        return OC_Config::getValue('overwritehost');
                }
                if (isset($_SERVER['HTTP_X_FORWARDED_HOST'])) {
@@ -53,7 +53,7 @@ class OC_Request {
        * Returns the server protocol. It respects reverse proxy servers and load balancers
        */
        public static function serverProtocol() {
-               if(OC_Config::getValue('overwriteprotocol', '')<>'' and self::isOverwriteCondition('protocol')) {
+               if(OC_Config::getValue('overwriteprotocol', '') !== '' and self::isOverwriteCondition('protocol')) {
                        return OC_Config::getValue('overwriteprotocol');
                }
                if (isset($_SERVER['HTTP_X_FORWARDED_PROTO'])) {
@@ -77,7 +77,7 @@ class OC_Request {
         */
        public static function requestUri() {
                $uri = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : '';
-               if (OC_Config::getValue('overwritewebroot', '') <> '' and self::isOverwriteCondition()) {
+               if (OC_Config::getValue('overwritewebroot', '') !== '' and self::isOverwriteCondition()) {
                        $uri = self::scriptName() . substr($uri, strlen($_SERVER['SCRIPT_NAME']));
                }
                return $uri;
@@ -92,7 +92,7 @@ class OC_Request {
         */
        public static function scriptName() {
                $name = $_SERVER['SCRIPT_NAME'];
-               if (OC_Config::getValue('overwritewebroot', '') <> '' and self::isOverwriteCondition()) {
+               if (OC_Config::getValue('overwritewebroot', '') !== '' and self::isOverwriteCondition()) {
                        $serverroot = str_replace("\\", '/', substr(__DIR__, 0, -4));
                        $suburi = str_replace("\\", "/", substr(realpath($_SERVER["SCRIPT_FILENAME"]), strlen($serverroot)));
                        $name = OC_Config::getValue('overwritewebroot', '') . $suburi;