[NTUSER] Optimize Window Snap Disabling (#5061)

win32ss/user/ntuser/defwnd.c

@@ -408,14 +408,14 @@ UserPaintCaption(PWND pWnd, INT Flags)
      * When themes are not enabled we can go on and paint the non client area.
      * However if we do that with themes enabled we will draw a classic frame.
      * This is solved by sending a themes specific message to notify the themes
-     * engine that the caption needs to be redrawn 
+     * engine that the caption needs to be redrawn.
      */
       if (gpsi->dwSRVIFlags & SRVINFO_APIHOOK)
       {
         /*
          * This will cause uxtheme to either paint the themed caption or call
          * RealUserDrawCaption in order to draw the classic caption when themes
-         * are disabled but the themes service is enabled
+         * are disabled but the themes service is enabled.
          */
          TRACE("UDCB Flags %08x\n", Flags);
          co_IntSendMessage(UserHMGetHandle(pWnd), WM_NCUAHDRAWCAPTION, Flags, 0);
@@ -544,9 +544,6 @@ IntDefWindowProc(
    PTHREADINFO pti = PsGetCurrentThreadWin32Thread();
    LRESULT lResult = 0;
    USER_REFERENCE_ENTRY Ref;
-   BOOL IsTaskBar;
-   DWORD Style;
-   DWORD ExStyle;
 
    if (Msg > WM_USER) return 0;
 
@@ -792,31 +789,26 @@ IntDefWindowProc(
                co_IntSendMessage(UserHMGetHandle(Wnd), WM_CONTEXTMENU, (WPARAM)UserHMGetHandle(Wnd), MAKELPARAM(-1, -1));
             }
          }
-         if (IS_KEY_DOWN(gafAsyncKeyState, VK_LWIN) || IS_KEY_DOWN(gafAsyncKeyState, VK_RWIN))
+         if (g_bWindowSnapEnabled && (IS_KEY_DOWN(gafAsyncKeyState, VK_LWIN) || IS_KEY_DOWN(gafAsyncKeyState, VK_RWIN)))
          {
+            BOOL IsTaskBar;
+            DWORD StyleTB;
+            DWORD ExStyleTB;
             HWND hwndTop = UserGetForegroundWindow();
             PWND topWnd = UserGetWindowObject(hwndTop);
 
-            /* Test for typical TaskBar ExStyle Values */
+            // We want to forbid snapping operations on the TaskBar
-            ExStyle = (topWnd->ExStyle & WS_EX_TOOLWINDOW);
+            // We use a heuristic for detecting the TaskBar Wnd by its typical Style & ExStyle Values
-            TRACE("ExStyle is '%x'.\n", ExStyle);
+            ExStyleTB = (topWnd->ExStyle & WS_EX_TOOLWINDOW);
+            StyleTB = (topWnd->style & (WS_POPUP | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN));
+            IsTaskBar = (StyleTB == (WS_POPUP | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN))
+                        && (ExStyleTB == WS_EX_TOOLWINDOW);
+            TRACE("ExStyle=%x Style=%x IsTaskBar=%d\n", ExStyleTB, StyleTB, IsTaskBar);
 
-            /* Test for typical TaskBar Style Values */
+            if (topWnd && !IsTaskBar)
-            Style = (topWnd->style & (WS_POPUP | WS_VISIBLE |
-                        WS_CLIPSIBLINGS | WS_CLIPCHILDREN));
-            TRACE("Style is '%x'.\n", Style);
-
-            /* Test for masked typical TaskBar Style and ExStyles to detect TaskBar */
-            IsTaskBar = (Style == (WS_POPUP | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN))
-                        && (ExStyle == WS_EX_TOOLWINDOW);
-            TRACE("This %s the TaskBar.\n", IsTaskBar ? "is" : "is not");
-
-            if (topWnd && !IsTaskBar)  /* Second test is so we are not touching the Taskbar */
             {
-               if ((topWnd->style & WS_THICKFRAME) == 0 || !g_bWindowSnapEnabled)
+               if ((topWnd->style & WS_THICKFRAME) == 0)
-               {
                   return 0;
-               }
 
                if (wParam == VK_DOWN)
                {

win32ss/user/ntuser/nonclient.c

@@ -256,8 +256,6 @@ DefWndDoSizeMove(PWND pwnd, WORD wParam)
    //PMONITOR mon = 0; Don't port sync from wine!!! This breaks explorer task bar sizing!!
    //                  The task bar can grow in size and can not reduce due to the change
    //                  in the work area.
-   DWORD ExStyleTB, StyleTB;
-   BOOL IsTaskBar;
 
    Style = pwnd->style;
    ExStyle = pwnd->ExStyle;
@@ -393,35 +391,33 @@ DefWndDoSizeMove(PWND pwnd, WORD wParam)
       if (!co_IntGetPeekMessage(&msg, 0, 0, 0, PM_REMOVE, TRUE)) break;
       if (IntCallMsgFilter( &msg, MSGF_SIZE )) continue;
 
-      /* Exit on button-up */
+      if (msg.message == WM_KEYDOWN && (msg.wParam == VK_RETURN || msg.wParam == VK_ESCAPE))
-      if (msg.message == WM_LBUTTONUP)
+         break; // Exit on Return or Esc
-      {
+
-         /* Test for typical TaskBar ExStyle Values */
+      if (!g_bWindowSnapEnabled && (msg.message == WM_LBUTTONUP))
+      { // If no WindowSnapEnabled: Exit on button-up immediately
+         break;
+      }
+      else if (g_bWindowSnapEnabled && msg.message == WM_LBUTTONUP)
+      { // If WindowSnapEnabled: Decide whether to snap before exiting
+         DWORD ExStyleTB, StyleTB;
+         BOOL IsTaskBar;
+
+         // We want to forbid snapping operations on the TaskBar
+         // We use a heuristic for detecting the TaskBar Wnd by its typical Style & ExStyle Values
          ExStyleTB = (ExStyle & WS_EX_TOOLWINDOW);
-         TRACE("ExStyle is '%x'.\n", ExStyleTB);
+         StyleTB = (Style & (WS_POPUP | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN));
-
-         /* Test for typical TaskBar Style Values */
-         StyleTB = (Style & (WS_POPUP | WS_VISIBLE |
-                        WS_CLIPSIBLINGS | WS_CLIPCHILDREN));
-         TRACE("Style is '%x'.\n", StyleTB);
-
-         /* Test for masked typical TaskBar Style and ExStyles to detect TaskBar */
          IsTaskBar = (StyleTB == (WS_POPUP | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN))
                      && (ExStyleTB == WS_EX_TOOLWINDOW);
-         TRACE("This %s the TaskBar.\n", IsTaskBar ? "is" : "is not");
+         TRACE("ExStyle=%x Style=%x IsTaskBar=%d\n", ExStyleTB, StyleTB, IsTaskBar);
 
          // check for snapping if was moved by caption
-         if (hittest == HTCAPTION && thickframe && (ExStyle & WS_EX_MDICHILD) == 0)
+         if (!IsTaskBar && hittest == HTCAPTION && thickframe && (ExStyle & WS_EX_MDICHILD) == 0)
          {
             RECT snapRect;
             BOOL doSideSnap = FALSE;
             UserSystemParametersInfo(SPI_GETWORKAREA, 0, &snapRect, 0);
 
-            /* if this is the taskbar, then we want to just exit */
-            if (IsTaskBar || !g_bWindowSnapEnabled)
-            {
-               break;
-            }
             // snap to left
             if (pt.x <= snapRect.left)
             {
@@ -459,13 +455,6 @@ DefWndDoSizeMove(PWND pwnd, WORD wParam)
          break;
       }
 
-      /* Exit on Return or Esc */
-      if (msg.message == WM_KEYDOWN &&
-          (msg.wParam == VK_RETURN || msg.wParam == VK_ESCAPE))
-      {
-         break;
-      }
-
       if ((msg.message != WM_KEYDOWN) && (msg.message != WM_MOUSEMOVE))
       {
          IntTranslateKbdMessage( &msg , 0 );
@@ -1285,7 +1274,7 @@ LRESULT NC_HandleNCCalcSize( PWND Wnd, WPARAM wparam, RECTL *Rect, BOOL Suspende
    SIZE WindowBorders;
    RECT OrigRect;
    LONG Style = Wnd->style;
-   LONG  exStyle = Wnd->ExStyle; 
+   LONG exStyle = Wnd->ExStyle;
 
    if (Rect == NULL)
    {
@@ -1700,7 +1689,7 @@ NC_HandleNCLButtonDblClk(PWND pWnd, WPARAM wParam, LPARAM lParam)
  *
  * Handle a WM_NCRBUTTONDOWN message. Called from DefWindowProc().
  */
-LRESULT NC_HandleNCRButtonDown( PWND pwnd, WPARAM wParam, LPARAM lParam ) 
+LRESULT NC_HandleNCRButtonDown(PWND pwnd, WPARAM wParam, LPARAM lParam)
 {
   MSG msg;
   INT hittest = wParam;