From 5bd03d8b97c4a3c0344f864dd36feb735f2103a2 Mon Sep 17 00:00:00 2001
From: Katayama Hirofumi MZ <katayama.hirofumi.mz@gmail.com>
Date: Thu, 8 Sep 2022 11:00:04 +0900
Subject: [PATCH] [NTUSER] Implement IntReorderKeyboardLayouts

This function is provided for KLF_REORDER flag.
CORE-11700
---
 win32ss/user/ntuser/kbdlayout.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/win32ss/user/ntuser/kbdlayout.c b/win32ss/user/ntuser/kbdlayout.c
index d41f53d3472..45e055d8758 100644
--- a/win32ss/user/ntuser/kbdlayout.c
+++ b/win32ss/user/ntuser/kbdlayout.c
@@ -745,10 +745,20 @@ co_UserActivateKeyboardLayout(
 VOID FASTCALL
 IntReorderKeyboardLayouts(
     _Inout_ PWINSTATION_OBJECT pWinSta,
-    _Inout_ PKL pKL)
+    _Inout_ PKL pNewKL)
 {
-    /* FIXME */
-    gspklBaseLayout = pKL;
+    PKL pOldKL = gspklBaseLayout;
+
+    if ((pWinSta->Flags & WSS_NOIO) || pNewKL == pOldKL)
+        return;
+
+    pNewKL->pklPrev->pklNext = pNewKL->pklNext;
+    pNewKL->pklNext->pklPrev = pNewKL->pklPrev;
+    pNewKL->pklNext = pOldKL;
+    pNewKL->pklPrev = pOldKL->pklPrev;
+    pOldKL->pklPrev->pklNext = pNewKL;
+    pOldKL->pklPrev = pNewKL;
+    gspklBaseLayout = pNewKL; /* Should we use UserAssignmentLock? */
 }
 
 /* Win: xxxActivateKeyboardLayout */