From f9170fd3fe07bf5c4d75f7d19e15ea58e7ed9895 Mon Sep 17 00:00:00 2001
From: Sylpheed RE agent <agent@localhost>
Date: Wed, 19 Aug 2026 08:35:26 +0000
Subject: [PATCH] [RE] xam_input: log the keystroke path that REACHES the
 driver

The existing [RE-INPUT] line only fires when IsUIActive() swallows a keystroke,
so its silence is ambiguous: it means either 'the game is polling and getting
nothing' or 'the game is not polling at all'. That is exactly the fork the
title-screen investigation is stuck on - with the sign-in dialog fixed the
swallow count is 0 and the title still does not respond to (A).

Adds two logs on the other side: a rate-limited count of calls that get past
IsUIActive to a driver, and one line per keystroke actually handed to the guest
(rare by construction - one per physical press - so every one is logged, with
user index, virtual key and flags).
---
 src/xenia/kernel/xam/xam_input.cc | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/xenia/kernel/xam/xam_input.cc b/src/xenia/kernel/xam/xam_input.cc
index 6b869916d..2034e35b1 100644
--- a/src/xenia/kernel/xam/xam_input.cc
+++ b/src/xenia/kernel/xam/xam_input.cc
@@ -211,6 +211,21 @@ dword_result_t XamInputGetKeystrokeEx_entry(
     return X_ERROR_SUCCESS;
   }
 
+  // RE aid, the other half of the pair above: count the calls that DO reach a
+  // driver, and log every keystroke actually handed to the guest. Without this,
+  // "the swallow log is silent" is ambiguous between "the game is polling and
+  // getting nothing" and "the game is not polling at all" — which is exactly
+  // the fork the title-screen investigation got stuck on
+  // (docs/re/ui-paint-order-third-permutation.md in the Reborn tree).
+  {
+    static std::atomic<uint32_t> polled{0};
+    const uint32_t n = polled.fetch_add(1, std::memory_order_relaxed);
+    if ((n % 600) == 0) {
+      XELOGI("[RE-INPUT] XamInputGetKeystrokeEx reached the driver ({} so far)",
+             n + 1);
+    }
+  }
+
   uint32_t user_index = *user_index_ptr;
   auto input_system = kernel_state()->emulator()->input_system();
   auto lock = input_system->lock();
@@ -239,6 +254,12 @@ dword_result_t XamInputGetKeystrokeEx_entry(
 
   if (XSUCCEEDED(result)) {
     *user_index_ptr = keystroke->user_index;
+    // Rare by construction — one per physical press — so log every one.
+    XELOGI(
+        "[RE-INPUT] XamInputGetKeystrokeEx -> user={} vk={:04X} flags={:04X} "
+        "(call flags {:08X})",
+        (uint32_t)keystroke->user_index, (uint32_t)keystroke->virtual_key,
+        (uint32_t)keystroke->flags, (uint32_t)flags);
   }
   return result;
 }