Use a timeout when sending broadcast messages.

dlls/user/dde/client.c

@@ -182,7 +182,8 @@ HCONV WINAPI DdeConnect(DWORD idInst, HSZ hszService, HSZ hszTopic,
     LeaveCriticalSection(&WDML_CritSect);
 
     /* note: sent messages shall not use packing */
-    SendMessageA(HWND_BROADCAST, WM_DDE_INITIATE, (WPARAM)hwndClient, MAKELPARAM(aSrv, aTpc));
+    SendMessageTimeoutW( HWND_BROADCAST, WM_DDE_INITIATE, (WPARAM)hwndClient, MAKELPARAM(aSrv, aTpc),
+                         SMTO_ABORTIFHUNG, 2000, NULL );
 
     EnterCriticalSection(&WDML_CritSect);
 

dlls/user/focus.c

@@ -110,7 +110,8 @@ static BOOL set_active_window( HWND hwnd, HWND *prev, BOOL mouse, BOOL focus )
     {
         /* send palette messages */
         if (SendMessageW( hwnd, WM_QUERYNEWPALETTE, 0, 0 ))
-            SendMessageW( HWND_BROADCAST, WM_PALETTEISCHANGING, (WPARAM)hwnd, 0 );
+            SendMessageTimeoutW( HWND_BROADCAST, WM_PALETTEISCHANGING, (WPARAM)hwnd, 0,
+                                 SMTO_ABORTIFHUNG, 2000, NULL );
 
         if (!(GetWindowLongW( hwnd, GWL_EXSTYLE ) & WS_EX_MANAGED))
             SetWindowPos( hwnd, HWND_TOP, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE | SWP_NOACTIVATE );

windows/painting.c

@@ -1467,7 +1467,8 @@ UINT WINAPI UserRealizePalette( HDC hDC )
     {
         /* send palette change notification */
         HWND hWnd = WindowFromDC( hDC );
-        if (hWnd) SendMessageA( HWND_BROADCAST, WM_PALETTECHANGED, (WPARAM)hWnd, 0L);
+        if (hWnd) SendMessageTimeoutW( HWND_BROADCAST, WM_PALETTECHANGED, (WPARAM)hWnd, 0,
+                                       SMTO_ABORTIFHUNG, 2000, NULL );
     }
     return realized;
 }

windows/syscolor.c

@@ -252,7 +252,8 @@ VOID WINAPI SetSysColors16( INT16 nChanges, const INT16 *lpSysColor,
 
     /* Send WM_SYSCOLORCHANGE message to all windows */
 
-    SendMessageA( HWND_BROADCAST, WM_SYSCOLORCHANGE, 0, 0 );
+    SendMessageTimeoutW( HWND_BROADCAST, WM_SYSCOLORCHANGE, 0, 0,
+                         SMTO_ABORTIFHUNG, 2000, NULL );
 
     /* Repaint affected portions of all visible windows */
 
@@ -276,7 +277,8 @@ BOOL WINAPI SetSysColors( INT nChanges, const INT *lpSysColor,
 
     /* Send WM_SYSCOLORCHANGE message to all windows */
 
-    SendMessageA( HWND_BROADCAST, WM_SYSCOLORCHANGE, 0, 0 );
+    SendMessageTimeoutW( HWND_BROADCAST, WM_SYSCOLORCHANGE, 0, 0,
+                         SMTO_ABORTIFHUNG, 2000, NULL );
 
     /* Repaint affected portions of all visible windows */
 

windows/sysparams.c

@@ -354,13 +354,16 @@ static HKEY get_volatile_regkey(void)
  */
 void SYSPARAMS_NotifyChange( UINT uiAction, UINT fWinIni )
 {
+    static const WCHAR emptyW[1];
+
     if (notify_change)
     {
         if (fWinIni & SPIF_UPDATEINIFILE)
         {
             if (fWinIni & (SPIF_SENDWININICHANGE | SPIF_SENDCHANGE))
-                SendMessageA(HWND_BROADCAST, WM_SETTINGCHANGE,
-                             uiAction, (LPARAM) "");
+                SendMessageTimeoutW(HWND_BROADCAST, WM_SETTINGCHANGE,
+                                    uiAction, (LPARAM) emptyW,
+                                    SMTO_ABORTIFHUNG, 2000, NULL );
         }
         else
         {