Can check if a user is allowed to access other user informations

functions/user.php

@@ -11,15 +11,31 @@
  *
  * @return Boolean True for a success
  */
-function user_login_required(){
-    if(!defined("userID")){
+function user_login_required() : bool{
+    if(!user_signed_in()){
         Rest_fatal_error(401, "This function requires user to be logged in!");
     }
 
-    //Check if userID is the number 0
-    if(userID == 0)
-        Rest_fatal_error(401, "This function requires user to be logged in!");
-
     //User logged in
     return true;
+}
+
+/**
+ * Check wether the user is signed in or not
+ *
+ * @return TRUE if user is signed in / FALSE else
+ */
+function user_signed_in() : bool {
+
+    //Check constant
+    if(!defined("userID"))
+        return false;
+    
+    //Check user ID
+    if(userID == 0)
+        return false;
+    
+    //User seems to be signed in
+    return true;
+
 }