From 1382dec0667a90cb2339da99fe7424f704314267 Mon Sep 17 00:00:00 2001
From: Gliniak <Gliniak93@gmail.com>
Date: Thu, 17 Sep 2020 18:15:56 +0200
Subject: [PATCH] XNotifyGetNext - Overall improvements

---
 src/xenia/kernel/xam/xam_notify.cc | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/src/xenia/kernel/xam/xam_notify.cc b/src/xenia/kernel/xam/xam_notify.cc
index 2504b472d..7da2c018a 100644
--- a/src/xenia/kernel/xam/xam_notify.cc
+++ b/src/xenia/kernel/xam/xam_notify.cc
@@ -38,15 +38,19 @@ DECLARE_XAM_EXPORT1(XamNotifyCreateListener, kNone, kImplemented);
 // https://github.com/CodeAsm/ffplay360/blob/master/Common/AtgSignIn.cpp
 dword_result_t XNotifyGetNext(dword_t handle, dword_t match_id,
                               lpdword_t id_ptr, lpdword_t param_ptr) {
-  if (!handle) {
-    return 0;
+  if (param_ptr) {
+    *param_ptr = 0;
   }
 
+  if (!id_ptr) {
+    return X_ERROR_INVALID_PARAMETER;
+  }
+  *id_ptr = 0;
   // Grab listener.
   auto listener =
       kernel_state()->object_table()->LookupObject<XNotifyListener>(handle);
   if (!listener) {
-    return 0;
+    return X_ERROR_INVALID_HANDLE;
   }
 
   bool dequeued = false;
@@ -61,21 +65,13 @@ dword_result_t XNotifyGetNext(dword_t handle, dword_t match_id,
     dequeued = listener->DequeueNotification(&id, &param);
   }
 
+  *id_ptr = dequeued ? id : 0;
   // param_ptr may be null - Ghost Recon Advanced Warfighter 2 Demo explicitly
   // passes nullptr in the code.
   // https://github.com/xenia-project/xenia/pull/1577
-  if (dequeued) {
-    *id_ptr = id;
-    if (param_ptr) {
-      *param_ptr = param;
-    }
-  } else {
-    *id_ptr = 0;
-    if (param_ptr) {
-      *param_ptr = 0;
-    }
+  if (param_ptr) {
+    *param_ptr = dequeued ? param : 0;
   }
-
   return dequeued ? 1 : 0;
 }
 DECLARE_XAM_EXPORT1(XNotifyGetNext, kNone, kImplemented);