user32: Let nulldrv return some dummy monitor information.

dlls/user32/driver.c

@@ -197,6 +197,8 @@ void USER_unload_driver(void)
  * These are fallbacks for entry points that are not implemented in the real driver.
  */
 
+#define NULLDRV_DEFAULT_HMONITOR ((HMONITOR)(UINT_PTR)(0x10000 + 1))
+
 static HKL CDECL nulldrv_ActivateKeyboardLayout( HKL layout, UINT flags )
 {
     return 0;
@@ -354,7 +356,12 @@ static LONG CDECL nulldrv_ChangeDisplaySettingsEx( LPCWSTR name, LPDEVMODEW mode
 
 static BOOL CDECL nulldrv_EnumDisplayMonitors( HDC hdc, LPRECT rect, MONITORENUMPROC proc, LPARAM lp )
 {
-    return FALSE;
+    RECT r = {0, 0, 640, 480};
+
+    TRACE("(%p, %p, %p, 0x%lx)\n", hdc, rect, proc, lp);
+
+    proc(NULLDRV_DEFAULT_HMONITOR, hdc, &r, lp);
+    return TRUE;
 }
 
 static BOOL CDECL nulldrv_EnumDisplaySettingsEx( LPCWSTR name, DWORD num, LPDEVMODEW mode, DWORD flags )
@@ -364,7 +371,23 @@ static BOOL CDECL nulldrv_EnumDisplaySettingsEx( LPCWSTR name, DWORD num, LPDEVM
 
 static BOOL CDECL nulldrv_GetMonitorInfo( HMONITOR handle, LPMONITORINFO info )
 {
+    RECT r = {0, 0, 640, 480};
+    static const WCHAR device[] = {'W','i','n','D','i','s','c',0};
+
+    TRACE("(%p, %p)\n", handle, info);
+
+    if (handle != NULLDRV_DEFAULT_HMONITOR)
+    {
+        SetLastError(ERROR_INVALID_MONITOR_HANDLE);
         return FALSE;
+    }
+
+    info->rcMonitor = r;
+    info->rcWork = r;
+    info->dwFlags = MONITORINFOF_PRIMARY;
+    if (info->cbSize >= sizeof(MONITORINFOEXW))
+        lstrcpyW( ((MONITORINFOEXW *)info)->szDevice, device );
+    return TRUE;
 }
 
 static BOOL CDECL nulldrv_CreateDesktopWindow( HWND hwnd )