[idd] helper: allow changing preferred mode

idd/LGIdd/CIndirectMonitorContext.cpp

@@ -71,7 +71,6 @@ reInit:
   }
 
   m_swapChain.reset(new CSwapChainProcessor(m_monitor, m_devContext, swapChain, m_dx11Device, m_dx12Device, newFrameEvent));
-  g_pipe.SetGPUStatus(m_dx11Device->IsSoftware());
 }
 
 void CIndirectMonitorContext::UnassignSwapChain()

idd/LGIdd/CPipeServer.cpp

@@ -114,6 +114,11 @@ void CPipeServer::Thread()
     DEBUG_TRACE("Client connected");
 
     m_connected = true;
+
+    for (const auto& msg : m_queue)
+      WriteMsg(msg);
+    m_queue.clear();
+
     while (m_running && m_connected)
     {
       //TODO: Read messages from the client
@@ -129,8 +134,14 @@ void CPipeServer::Thread()
   DEBUG_TRACE("Pipe thread shutdown");
 }
 
-void CPipeServer::WriteMsg(LGPipeMsg & msg)
+void CPipeServer::WriteMsg(const LGPipeMsg & msg)
 {
+  if (!m_connected)
+  {
+    m_queue.push_back(msg);
+    return;
+  }
+
   DWORD written;
   if (!WriteFile(m_pipe.Get(), &msg, sizeof(msg), &written, NULL))
   {
@@ -151,6 +162,7 @@ void CPipeServer::WriteMsg(LGPipeMsg & msg)
 
 void CPipeServer::SetCursorPos(uint32_t x, uint32_t y)
 {
+  // do not send cursor messages if we are not connected or they will end up queued
   if (!m_connected)
     return;
 
@@ -164,9 +176,6 @@ void CPipeServer::SetCursorPos(uint32_t x, uint32_t y)
 
 void CPipeServer::SetDisplayMode(uint32_t width, uint32_t height, uint32_t refresh)
 {
-  if (!m_connected)
-    return;
-
   LGPipeMsg msg;
   msg.size                = sizeof(msg);
   msg.type                = LGPipeMsg::SETDISPLAYMODE;
@@ -178,9 +187,6 @@ void CPipeServer::SetDisplayMode(uint32_t width, uint32_t height, uint32_t refre
 
 void CPipeServer::SetGPUStatus(bool software)
 {
-  if (!m_connected)
-    return;
-
   LGPipeMsg msg;
   msg.size               = sizeof(msg);
   msg.type               = LGPipeMsg::GPUSTATUS;

idd/LGIdd/CPipeServer.h

@@ -24,6 +24,7 @@
 #include <wdf.h>
 #include <stdint.h>
 #include <wrl.h>
+#include <vector>
 
 #include "PipeMsg.h"
 
@@ -36,6 +37,7 @@ class CPipeServer
   private:
     HandleT<HANDLENullTraits> m_pipe;
     HandleT<HANDLENullTraits> m_thread;
+    std::vector<LGPipeMsg>    m_queue;
 
     bool m_running   = false;
     bool m_connected = false;
@@ -45,7 +47,7 @@ class CPipeServer
     static DWORD WINAPI _pipeThread(LPVOID lpParam) { ((CPipeServer*)lpParam)->Thread(); return 0; }
     void Thread();
 
-    void WriteMsg(LGPipeMsg & msg);
+    void WriteMsg(const LGPipeMsg & msg);
 
   public:
     ~CPipeServer() { DeInit(); }

idd/LGIdd/CSwapChainProcessor.cpp

@@ -22,6 +22,7 @@
 
 #include <avrt.h>
 #include "CDebug.h"
+#include "CPipeServer.h"
 
 CSwapChainProcessor::CSwapChainProcessor(IDDCX_MONITOR monitor, CIndirectDeviceContext* devContext, IDDCX_SWAPCHAIN hSwapChain,
     std::shared_ptr<CD3D11Device> dx11Device, std::shared_ptr<CD3D12Device> dx12Device, HANDLE newFrameEvent) :
@@ -130,6 +131,10 @@ void CSwapChainProcessor::SwapChainThreadCore()
   m_lastShapeId = 0;
   m_thread[1].Attach(CreateThread(nullptr, 0, _CursorThread, this, 0, nullptr));
 
+  // postpone sending this to ensure we dont spam messages if we end up in a
+  // restart loop while waiting for a valid configuration
+  g_pipe.SetGPUStatus(m_dx11Device->IsSoftware());
+
   UINT lastFrameNumber = 0;
   for (;;)
   {

idd/LGIddHelper/CConfigWindow.cpp

@@ -89,7 +89,7 @@ void CConfigWindow::updateFont()
   }
 
   for (HWND child : std::initializer_list<HWND>({
-    *m_version, *m_modeGroup, *m_modeBox, *m_widthLabel, *m_heightLabel, *m_refreshLabel,
+    *m_version, *m_modeGroup, *m_modeBox, *m_widthLabel, *m_heightLabel, *m_refreshLabel, *m_modePreferred,
     *m_modeWidth, *m_modeHeight, *m_modeRefresh, *m_modeUpdate, *m_modeDelete, *m_modeReset,
     *m_autosizeGroup, *m_defRefreshLabel, *m_defRefresh, *m_defRefreshHz,
     *m_prefGroup, *m_prefNoGPU,
@@ -97,13 +97,20 @@ void CConfigWindow::updateFont()
     SendMessage(child, WM_SETFONT, (WPARAM)m_font.Get(), 1);
 }
 
-void CConfigWindow::updateModeList()
+int CConfigWindow::updateModeList(int wanted)
 {
+  int result = 0;
   m_modeBox->addItem(L"<add new>", -1);
 
   auto &modes = *m_modes;
   for (size_t i = 0; i < modes.size(); ++i)
-    m_modeBox->addItem(modes[i].toString(), i);
+  {
+    int idx = m_modeBox->addItem(modes[i].toString(), i);
+    if (wanted == i)
+      result = idx;
+  }
+
+  return result;
 }
 
 LRESULT CConfigWindow::handleMessage(UINT uMsg, WPARAM wParam, LPARAM lParam)
@@ -154,6 +161,7 @@ LRESULT CConfigWindow::onCreate()
   m_modeWidth.reset(new CEditWidget(WS_CHILD | WS_VISIBLE | WS_TABSTOP | ES_LEFT | ES_NUMBER, m_hwnd));
   m_modeHeight.reset(new CEditWidget(WS_CHILD | WS_VISIBLE | WS_TABSTOP | ES_LEFT | ES_NUMBER, m_hwnd));
   m_modeRefresh.reset(new CEditWidget(WS_CHILD | WS_VISIBLE | WS_TABSTOP | ES_LEFT | ES_NUMBER, m_hwnd));
+  m_modePreferred.reset(new CCheckbox(L"prefer", WS_CHILD | WS_VISIBLE, m_hwnd));
 
   m_modeUpdate.reset(new CButton(L"Save", WS_CHILD | WS_VISIBLE | WS_TABSTOP, m_hwnd));
   m_modeDelete.reset(new CButton(L"Delete", WS_CHILD | WS_VISIBLE | WS_TABSTOP, m_hwnd));
@@ -206,6 +214,7 @@ LRESULT CConfigWindow::onResize(DWORD width, DWORD height)
   pos.pinBottomLeft(*m_modeWidth, 75, 96, 50, 20);
   pos.pinBottomLeft(*m_modeHeight, 75, 72, 50, 20);
   pos.pinBottomLeft(*m_modeRefresh, 75, 48, 50, 20);
+  pos.pinBottomLeft(*m_modePreferred, 130, 96, 70, 20);
   pos.pinBottomLeft(*m_modeUpdate, 24, 20, 50, 24);
   pos.pinBottomLeft(*m_modeDelete, 75, 20, 50, 24);
   pos.pinBottomLeft(*m_modeReset, 126, 20, 50, 24);
@@ -238,6 +247,7 @@ void CConfigWindow::onModeListSelectChange()
     m_modeWidth->setNumericValue(mode.width);
     m_modeHeight->setNumericValue(mode.height);
     m_modeRefresh->setNumericValue(mode.refresh);
+    m_modePreferred->setChecked(mode.preferred);
   }
   EnableWindow(*m_modeUpdate, TRUE);
   EnableWindow(*m_modeDelete, index >= 0);
@@ -249,6 +259,10 @@ LRESULT CConfigWindow::onCommand(WORD id, WORD code, HWND hwnd)
   {
     onModeListSelectChange();
   }
+  else if (m_modePreferred && hwnd == *m_modePreferred && code == BN_CLICKED && m_modes)
+  {
+    m_modePreferred->setChecked(!m_modePreferred->isChecked());
+  }
   else if (m_modeUpdate && hwnd == *m_modeUpdate && code == BN_CLICKED && m_modes)
   {
     int sel = m_modeBox->getSel();
@@ -258,21 +272,23 @@ LRESULT CConfigWindow::onCommand(WORD id, WORD code, HWND hwnd)
     int index = m_modeBox->getData(sel);
     auto &mode = index >= 0 ? (*m_modes)[index] : m_modes->emplace_back();
 
+    for (auto &mode : *m_modes)
+      mode.preferred = false;
+
     try
     {
       mode.width = m_modeWidth->getNumericValue();
       mode.height = m_modeHeight->getNumericValue();
       mode.refresh = m_modeRefresh->getNumericValue();
+      mode.preferred = m_modePreferred->isChecked();
     }
     catch (std::logic_error&)
     {
       return 0;
     }
 
-    if (index >= 0)
+    m_modeBox->clear();
-      m_modeBox->delItem(sel);
+    m_modeBox->setSel(updateModeList(index));
-
-    m_modeBox->setSel(m_modeBox->addItem(mode.toString().c_str(), index));
 
     LRESULT result = m_settings.setModes(*m_modes);
     if (result != ERROR_SUCCESS)

idd/LGIddHelper/CConfigWindow.h

@@ -49,6 +49,7 @@ class CConfigWindow : public CWindow
   std::unique_ptr<CEditWidget> m_modeWidth;
   std::unique_ptr<CEditWidget> m_modeHeight;
   std::unique_ptr<CEditWidget> m_modeRefresh;
+  std::unique_ptr<CCheckbox> m_modePreferred;
 
   std::unique_ptr<CButton> m_modeUpdate;
   std::unique_ptr<CButton> m_modeDelete;
@@ -72,7 +73,7 @@ class CConfigWindow : public CWindow
 
   void getMinimumSize(LONG &width, LONG &height);
   void updateFont();
-  void updateModeList();
+  int updateModeList(int wanted = -1);
   void onModeListSelectChange();
 
   virtual LRESULT handleMessage(UINT uMsg, WPARAM wParam, LPARAM lParam) override;

idd/LGIddHelper/CNotifyWindow.cpp

@@ -20,13 +20,13 @@
 
 #include "CNotifyWindow.h"
 #include "CConfigWindow.h"
-#include "Devices.h"
 #include <CDebug.h>
 #include <windowsx.h>
 #include <strsafe.h>
 
 #define WM_NOTIFY_ICON     (WM_USER)
 #define WM_CLEAN_UP_CONFIG (WM_USER+1)
+#define WM_NO_GPU          (WM_USER+2)
 
 #define ID_MENU_SHOW_LOG 3000
 #define ID_MENU_SHOW_CONFIG 3001
@@ -81,6 +81,10 @@ LRESULT CNotifyWindow::handleMessage(UINT uMsg, WPARAM wParam, LPARAM lParam)
     }
     return 0;
 
+  case WM_NO_GPU:
+    handleNoGPUNotification();
+    return 0;
+
   default:
     if (s_taskbarCreated && uMsg == s_taskbarCreated)
     {
@@ -162,20 +166,14 @@ void CNotifyWindow::registerIcon()
 
   if (!Shell_NotifyIcon(NIM_SETVERSION, &m_iconData))
     DEBUG_ERROR_HR(GetLastError(), "Shell_NotifyIcon(NIM_SETVERSION)");
-
-  bool hasGPU;
-  if (!checkGPU(hasGPU))
-    DEBUG_ERROR("Failed to check if the system has a GPU");
-  else if (hasGPU)
-    DEBUG_INFO("GPU identified");
-  else
-  {
-    DEBUG_INFO("System has no GPU");
-    noGPUNotification();
-  }
 }
 
 void CNotifyWindow::noGPUNotification()
+{
+  PostMessage(m_hwnd, WM_NO_GPU, 0, 0);
+}
+
+void CNotifyWindow::handleNoGPUNotification()
 {
   CRegistrySettings settings;
   LSTATUS error = settings.open();

idd/LGIddHelper/CNotifyWindow.h

@@ -36,7 +36,7 @@ class CNotifyWindow : public CWindow
 
   LRESULT onNotifyIcon(UINT uEvent, WORD wIconId, int x, int y);
   void registerIcon();
-  void noGPUNotification();
+  void handleNoGPUNotification();
 
   virtual LRESULT handleMessage(UINT uMsg, WPARAM wParam, LPARAM lParam) override;
   virtual LRESULT onCreate() override;
@@ -44,11 +44,26 @@ class CNotifyWindow : public CWindow
   virtual LRESULT onDestroy() override;
   virtual LRESULT onFinal() override;
 
-public:
   CNotifyWindow();
   ~CNotifyWindow() override;
+
+public:
+  CNotifyWindow(const CNotifyWindow&) = delete;
+  CNotifyWindow& operator=(const CNotifyWindow&) = delete;
+
+  CNotifyWindow(CNotifyWindow&&) = delete;
+  CNotifyWindow& operator=(CNotifyWindow&&) = delete;
+
+  static CNotifyWindow& instance()
+  {
+    static CNotifyWindow window;
+    return window;
+  }
+
   static bool registerClass();
 
+  void noGPUNotification();
+
   HWND hwndDialog();
   void close();
 };

idd/LGIddHelper/CPipeClient.cpp

@@ -20,6 +20,7 @@
 
 #include "CPipeClient.h"
 #include "CDebug.h"
+#include "CNotifyWindow.h"
 
 #include <setupapi.h>
 #include <tchar.h>
@@ -307,5 +308,6 @@ void CPipeClient::HandleSetDisplayMode(const LGPipeMsg& msg)
 
 void CPipeClient::HandleGPUStatus(const LGPipeMsg& msg)
 {
-  // TODO: implement me
+  if (msg.gpuStatus.software)
+    CNotifyWindow::instance().noGPUNotification();
 }

idd/LGIddHelper/Devices.cpp

@@ -1,106 +0,0 @@
-/**
- * Looking Glass
- * Copyright © 2017-2026 The Looking Glass Authors
- * https://looking-glass.io
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc., 59
- * Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-#include "Devices.h"
-#include <windows.h>
-#include <devguid.h>
-#include <setupapi.h>
-#include <CDebug.h>
-
-inline static bool wprefix(const wchar_t *pre, const wchar_t *str)
-{
-  return wcsncmp(pre, str, wcslen(pre)) == 0;
-}
-
-bool checkGPU(bool &found)
-{
-  found = false;
-
-  HDEVINFO hDevInfo = SetupDiGetClassDevsW(&GUID_DEVCLASS_DISPLAY, NULL, NULL, DIGCF_PRESENT);
-  if (hDevInfo == INVALID_HANDLE_VALUE)
-  {
-    DEBUG_WARN_HR(GetLastError(), L"SetupDiGetClassDevsW");
-    return false;
-  }
-
-  SP_DEVINFO_DATA devInfo = { 0 };
-  devInfo.cbSize = sizeof devInfo;
-
-  for (DWORD dwIndex = 0; SetupDiEnumDeviceInfo(hDevInfo, dwIndex, &devInfo); ++dwIndex)
-  {
-    DWORD dwSizeRequired;
-    DWORD dwPropertyType;
-    SetupDiGetDeviceRegistryPropertyW(hDevInfo, &devInfo, SPDRP_HARDWAREID, &dwPropertyType, NULL, 0, &dwSizeRequired);
-
-    DWORD dwLastError = GetLastError();
-    if (dwLastError == ERROR_INVALID_DATA)
-      continue;
-    else if (dwLastError != ERROR_INSUFFICIENT_BUFFER)
-    {
-      DEBUG_WARN_HR(GetLastError(), L"SetupDiGetDeviceRegistryPropertyW(SPDRP_HARDWAREID) size calculation");
-      goto fail;
-    }
-
-    if (dwPropertyType != REG_MULTI_SZ)
-    {
-      DEBUG_WARN(L"SetupDiGetDeviceRegistryPropertyW(SPDRP_HARDWAREID) returned wrong type");
-      goto fail;
-    }
-
-    LPWSTR lpBuffer = (LPWSTR)malloc(dwSizeRequired);
-    if (!lpBuffer)
-    {
-      DEBUG_WARN(L"failed to allocate memory for SetupDiGetDeviceRegistryPropertyW(SPDRP_HARDWAREID)");
-      goto fail;
-    }
-
-    if (!SetupDiGetDeviceRegistryPropertyW(hDevInfo, &devInfo, SPDRP_HARDWAREID, &dwPropertyType, (PBYTE)lpBuffer, dwSizeRequired, NULL))
-    {
-      DEBUG_WARN_HR(GetLastError(), L"SetupDiGetDeviceRegistryPropertyW(SPDRP_HARDWAREID) for real");
-      free(lpBuffer);
-      goto fail;
-    }
-
-    for (LPWSTR lpHwId = lpBuffer; *lpHwId; lpHwId += wcslen(lpBuffer) + 1)
-    {
-      if (
-        wprefix(L"PCI\\VEN_10DE&", lpHwId) || // Nvidia
-        wprefix(L"PCI\\VEN_1002&", lpHwId) || // AMD
-        wprefix(L"PCI\\VEN_8086&", lpHwId)    // Intel
-      )
-      {
-        found = true;
-        break;
-      }
-    }
-
-    free(lpBuffer);
-
-    if (found)
-      break;
-  }
-
-  SetupDiDestroyDeviceInfoList(hDevInfo);
-  return true;
-
-fail:
-  SetupDiDestroyDeviceInfoList(hDevInfo);
-  return false;
-}

idd/LGIddHelper/Devices.h

@@ -1,23 +0,0 @@
-/**
- * Looking Glass
- * Copyright © 2017-2026 The Looking Glass Authors
- * https://looking-glass.io
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc., 59
- * Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-#pragma once
-
-bool checkGPU(bool &found);

idd/LGIddHelper/LGIddHelper.vcxproj

@@ -191,7 +191,6 @@ copy /Y "$(ProjectDir)VERSION" "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd
     <ClCompile Include="CStaticWidget.cpp" />
     <ClCompile Include="CWidget.cpp" />
     <ClCompile Include="CWindow.cpp" />
-    <ClCompile Include="Devices.cpp" />
     <ClCompile Include="main.cpp" />
     <ClCompile Include="UIHelpers.cpp" />
   </ItemGroup>
@@ -208,7 +207,6 @@ copy /Y "$(ProjectDir)VERSION" "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd
     <ClInclude Include="CRegistrySettings.h" />
     <ClInclude Include="CStaticWidget.h" />
     <ClInclude Include="CWidget.h" />
-    <ClInclude Include="Devices.h" />
     <ClInclude Include="UIHelpers.h" />
     <ClInclude Include="CWindow.h" />
   </ItemGroup>

idd/LGIddHelper/LGIddHelper.vcxproj.filters

@@ -22,14 +22,12 @@
     <ClCompile Include="CPipeClient.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
     <ClCompile Include="CWindow.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
     <ClCompile Include="CNotifyWindow.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
     <ClCompile Include="CConfigWindow.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
@@ -39,7 +37,6 @@
     <ClCompile Include="CWidget.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
     <ClCompile Include="CRegistrySettings.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
@@ -49,18 +46,16 @@
     <ClCompile Include="UIHelpers.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
     <ClCompile Include="CGroupBox.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
     <ClCompile Include="CButton.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
     <ClCompile Include="CEditWidget.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="Devices.cpp">
+    <ClCompile Include="CCheckbox.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
   </ItemGroup>
@@ -69,16 +64,12 @@
     <ClInclude Include="CPipeClient.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
     <ClInclude Include="CWindow.h">
       <Filter>Header Files</Filter>
     </ClInclude>
     <ClInclude Include="CNotifyWindow.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
     <ClInclude Include="CConfigWindow.h">
       <Filter>Header Files</Filter>
     </ClInclude>
@@ -91,29 +82,22 @@
     <ClInclude Include="UIHelpers.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
     <ClInclude Include="CRegistrySettings.h">
       <Filter>Header Files</Filter>
     </ClInclude>
     <ClInclude Include="CListBox.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
     <ClInclude Include="CGroupBox.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
-    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
     <ClInclude Include="CButton.h">
       <Filter>Header Files</Filter>
     </ClInclude>
     <ClInclude Include="CEditWidget.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <ClInclude Include="Devices.h">
+    <ClInclude Include="CCheckbox.h">
       <Filter>Header Files</Filter>
     </ClInclude>
   </ItemGroup>

idd/LGIddHelper/main.cpp

@@ -113,11 +113,13 @@ int WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _
     return EXIT_FAILURE;
   }
 
+  CNotifyWindow& window = CNotifyWindow::instance();
+
+  // the pipe must be initialized after the CNotifyWindow
+  // has been created to avoid a potential race
   if (!g_pipe.Init())
     return EXIT_FAILURE;
 
-  CNotifyWindow window;
-
   HANDLE hWait;
   if (!RegisterWaitForSingleObject(&hWait, hParent.Get(), DestroyNotifyWindow, &window, INFINITE, WT_EXECUTEONLYONCE))
     DEBUG_ERROR_HR(GetLastError(), "Failed to RegisterWaitForSingleObject");