[PATCH v2 0/2] MR9398: Don't try to activate a window in set_window_pos if it's set as active in GUITHREADINFO.

[Santino Mazza (＠tati)]

This prevents a window from getting reactivated when calling `SetWindowPos` inside the WM_ACTIVATE handler. For now I only was able to reproduce this by triggering a change in the active window from X11 with an alt-tab or by clicking another window, I was not able to write a wine test for this.

This test program works for reproducing it.
```c
#include <windows.h>

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    if (uMsg == WM_ACTIVATE) {
        SetWindowPos(hwnd, 0, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);
    }

done:
    return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR pCmdLine,
                   int nCmdShow) {
    HWND hwnd;
    const char CLASS_NAME[] = "class";
    WNDCLASSA wc = {};
    wc.lpfnWndProc = WindowProc;
    wc.hInstance = hInstance;
    wc.lpszClassName = CLASS_NAME;

RegisterClass(&wc);

hwnd =
    CreateWindowEx(0, CLASS_NAME, "test", 0,
                    4, 4, 1024, 768, NULL, NULL, hInstance, NULL);

ShowWindow(hwnd, SW_SHOW);

MSG msg;
    while (TRUE) {
        GetMessage(&msg, NULL, 0, 0);
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
}
```

--
  v2: win32u: Don't activate a window that is being deactivated.
      win32u: Set WIN_IS_DEACTIVATING for previous window.

https://gitlab.winehq.org/wine/wine/-/merge_requests/9398

[PATCH v2 1/2] win32u: Set WIN_IS_DEACTIVATING for previous window.

[Santino Mazza]

From: Santino Mazza

---
 dlls/win32u/input.c          | 10 ++++++----
 dlls/win32u/ntuser_private.h |  1 +
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/dlls/win32u/input.c b/dlls/win32u/input.c
index 084ee561f30..d5ecbb33958 100644
--- a/dlls/win32u/input.c
+++ b/dlls/win32u/input.c
@@ -1991,7 +1991,7 @@ static HWND set_focus_window( HWND hwnd )
 BOOL set_active_window( HWND hwnd, HWND *prev, BOOL mouse, BOOL focus, DWORD new_active_thread_id )
 {
     HWND previous = get_active_window();
-    BOOL ret;
+    BOOL ret = TRUE;
     DWORD old_thread, new_thread;
     CBTACTIVATESTRUCT cbt;

@@ -2005,6 +2005,7 @@ BOOL set_active_window( HWND hwnd, HWND *prev, BOOL mouse, BOOL focus, DWORD new
     cbt.fMouse     = mouse;
     cbt.hWndActive = previous;
     if (call_hooks( WH_CBT, HCBT_ACTIVATE, (WPARAM)hwnd, (LPARAM)&cbt, sizeof(cbt) )) return FALSE;
+    if (previous) win_set_flags(previous, WIN_IS_DEACTIVATING, 0);

if (is_window( previous ))
     {
@@ -2020,7 +2021,7 @@ BOOL set_active_window( HWND hwnd, HWND *prev, BOOL mouse, BOOL focus, DWORD new
             previous = wine_server_ptr_handle( reply->previous );
     }
     SERVER_END_REQ;
-    if (!ret) return FALSE;
+    if (!ret) goto done;
     if (prev) *prev = previous;
     if (previous == hwnd) goto done;

@@ -2032,7 +2033,7 @@ BOOL set_active_window( HWND hwnd, HWND *prev, BOOL mouse, BOOL focus, DWORD new
         if (send_message( hwnd, WM_QUERYNEWPALETTE, 0, 0 ))
             send_message_timeout( HWND_BROADCAST, WM_PALETTEISCHANGING, (WPARAM)hwnd, 0,
                                   SMTO_ABORTIFHUNG, 2000, FALSE );
-        if (!is_window(hwnd)) return FALSE;
+        if (!(ret = is_window(hwnd))) goto done;
     }

old_thread = previous ? get_window_thread( previous, NULL ) : 0;
@@ -2091,12 +2092,13 @@ BOOL set_active_window( HWND hwnd, HWND *prev, BOOL mouse, BOOL focus, DWORD new
     }

done:
+    if (previous) win_set_flags(previous, 0, WIN_IS_DEACTIVATING);
     if (hwnd)
     {
         if (hwnd == NtUserGetForegroundWindow()) user_driver->pActivateWindow( hwnd, previous );
         clip_fullscreen_window( hwnd, FALSE );
     }
-    return TRUE;
+    return ret;
 }

/**********************************************************************
diff --git a/dlls/win32u/ntuser_private.h b/dlls/win32u/ntuser_private.h
index 1d0131e5886..0be90de5663 100644
--- a/dlls/win32u/ntuser_private.h
+++ b/dlls/win32u/ntuser_private.h
@@ -87,6 +87,7 @@ typedef struct tagWND
 #define WIN_NEEDS_SHOW_OWNEDPOPUP 0x0020 /* WM_SHOWWINDOW:SC_SHOW must be sent in the next ShowOwnedPopup call */
 #define WIN_CHILDREN_MOVED        0x0040 /* children may have moved, ignore stored positions */
 #define WIN_HAS_IME_WIN           0x0080 /* the window has been registered with imm32 */
+#define WIN_IS_DEACTIVATING       0x0100 /* window is being deactivated */

#define WND_OTHER_PROCESS ((WND *)1)  /* returned by get_win_ptr on unknown window handles */
 #define WND_DESKTOP       ((WND *)2)  /* returned by get_win_ptr on the desktop window */

[PATCH v2 2/2] win32u: Don't activate a window that is being deactivated.

[Santino Mazza]

From: Santino Mazza

This fixes a difference in behavior between Wine and Windows, where in Wine
it's possible to immediatly reactivate a window by calling SetWindowPos or
SetForegroundWindow inside the WM_ACTIVATE handler.
In Windows this isn't possible.
---
 dlls/win32u/input.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/dlls/win32u/input.c b/dlls/win32u/input.c
index d5ecbb33958..0b7d745d30d 100644
--- a/dlls/win32u/input.c
+++ b/dlls/win32u/input.c
@@ -2207,6 +2207,7 @@ BOOL set_foreground_window( HWND hwnd, BOOL mouse )
     DWORD new_thread_id;
     HWND previous = 0;

+    if (win_get_flags(hwnd) & WIN_IS_DEACTIVATING) return TRUE;
     if (mouse) hwnd = get_full_window_handle( hwnd );
     new_thread_id = get_window_thread( hwnd, NULL );

[Rémi Bernon (＠rbernon)]

Rémi Bernon (@rbernon) commented about dlls/win32u/input.c:
>          previous = wine_server_ptr_handle( reply->previous );

Seems to me that `previous` might change here.

[Rémi Bernon (＠rbernon)]

Rémi Bernon (@rbernon) commented about dlls/win32u/input.c:
>      send_message( previous, WM_ACTIVATE,
>                    MAKEWPARAM( WA_INACTIVE, is_iconic(previous) ), (LPARAM)hwnd );
>  }

Should we then maybe reduce the flag scope to this?

```suggestion:-8+0
    if (is_window( previous ))
    {
        win_set_flags(previous, WIN_IS_DEACTIVATING, 0);
        send_message( previous, WM_NCACTIVATE, FALSE, (LPARAM)hwnd );
        send_message( previous, WM_ACTIVATE,
                      MAKEWPARAM( WA_INACTIVE, is_iconic(previous) ), (LPARAM)hwnd );
        win_set_flags(previous, 0, WIN_IS_DEACTIVATING);
    }

```

[Rémi Bernon (＠rbernon)]

Unrelated to the comments above and unfortunately, after looking at https://bugs.winehq.org/show_bug.cgi?id=58167 which seems like a similar issue, I think there's more to it that just preventing reactivation *during* the WM_ACTIVATE message. It's maybe a slightly different issue but I think it's related and I'll see if we can fix both at once.