Issue #1173 - Protect more entry points with try-catch blocks

src/plugin/PluginClass.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 74 matching lines @@
     int Width() const
     {
       return right - left;
     }
   };
 }
 
 CPluginClass::CPluginClass()
   : m_webBrowser2(nullptr)
 {
+  DEBUG_GENERAL([this]() -> std::wstring
+    {
+      std::wstring s = L"CPluginClass::<constructor>, this = ";
+      s += ToHexLiteral(this);
+      return s;
+    }());
+
   //Use this line to debug memory leaks
   //    _CrtDumpMemoryLeaks();
 
   m_isAdvised = false;
   m_hTabWnd = NULL;
   m_hStatusBarWnd = NULL;
   m_hPaneWnd = NULL;
   m_nPaneWidth = 0;
   m_pWndProcStatus = NULL;
   m_hTheme = NULL;
   m_isInitializedOk = false;
 
 
-  m_tab = new CPluginTab(this);
+  m_tab = new CPluginTab();
 
   Dictionary::Create(GetBrowserLanguage());
 }
 
 CPluginClass::~CPluginClass()
 {
+  DEBUG_GENERAL([this]() -> std::wstring
+    {
+      std::wstring s = L"CPluginClass::<destructor>, this = ";
+      s += ToHexLiteral(this);
+      return s;
+    }());
+
   delete m_tab;
 }
 
 HWND CPluginClass::GetBrowserHWND() const
 {
   if (!m_webBrowser2)
   {
     DEBUG_ERROR_LOG(0, 0, 0, "CPluginClass::GetBrowserHWND - Reached with m_webBrowser2 == nullptr");
     return nullptr;
   }
@@ skipping 65 matching lines @@
  * 'unknownSite' will be null. Extraordinarily, this is sometimes _not_ called when IE
  * is shutting down. Thus 'SetSite(nullptr)' has some similarities with a destructor,
  * but it is not a proper substitute for one.
  */
 STDMETHODIMP CPluginClass::SetSite(IUnknown* unknownSite)
 {
   try
   {
     if (unknownSite)
     {
-
-      DEBUG_GENERAL(L"================================================================================\nNEW TAB UI\n================================================================================")
+      DEBUG_GENERAL(L"================================================================================\nNEW TAB UI\n================================================================================");
 
       HRESULT hr = ::CoInitialize(NULL);
       if (FAILED(hr))
       {
         DEBUG_ERROR_LOG(hr, PLUGIN_ERROR_SET_SITE, PLUGIN_ERROR_SET_SITE_COINIT, "Class::SetSite - CoInitialize");
       }
 
       /*
        * We were instantiated as a BHO, so our site is always of type IWebBrowser2.
        */
       m_webBrowser2 = ATL::CComQIPtr<IWebBrowser2>(unknownSite);
       if (!m_webBrowser2)
       {
         throw std::logic_error("CPluginClass::SetSite - Unable to convert site pointer to IWebBrowser2*");
       }
+      DEBUG_GENERAL([this]() -> std::wstring
+        {
+          std::wstringstream ss;
+          ss << L"CPluginClass::SetSite, this = " << ToHexLiteral(this);
+          ss << L", browser = " << ToHexLiteral(m_webBrowser2);
+          return ss.str();
+        }());
 
       //register the mimefilter
       //and only mimefilter
       //on some few computers the mimefilter does not get properly registered when it is done on another thread
       s_criticalSectionLocal.Lock();
       {
         // Always register on startup, then check if we need to unregister in a separate thread
         s_mimeFilter = CPluginClientFactory::GetMimeFilterClientInstance();
         s_asyncWebBrowser2 = unknownSite;
         s_instances.insert(this);
       }
       s_criticalSectionLocal.Unlock();
 
       try
       {
-        DEBUG_GENERAL("Loaded as BHO");
         HRESULT hr = DispEventAdvise(m_webBrowser2);
         if (SUCCEEDED(hr))
         {
           m_isAdvised = true;
           try
           {
             std::thread startInitObjectThread(StartInitObject, this);
             startInitObjectThread.detach(); // TODO: but actually we should wait for the thread in the dtr.
           }
           catch (const std::system_error& ex)
           {
             DEBUG_SYSTEM_EXCEPTION(ex, PLUGIN_ERROR_THREAD, PLUGIN_ERROR_MAIN_THREAD_CREATE_PROCESS, 
               "Class::Thread - Failed to create StartInitObject thread");
           }
         }
         else
         {
           DEBUG_ERROR_LOG(hr, PLUGIN_ERROR_SET_SITE, PLUGIN_ERROR_SET_SITE_ADVICE, "Class::SetSite - Advise");
         }
       }
       catch (const std::runtime_error& ex)
       {
         DEBUG_EXCEPTION(ex);
         Unadvise();
       }
     }
     else
     {
+      DEBUG_GENERAL([this]() -> std::wstring
+      {
+        std::wstringstream ss;
+        ss << L"CPluginClass::SetSite, this = " << ToHexLiteral(this);
+        ss << L", browser = nullptr";
+        return ss.str();
+      }());
+
       Unadvise();
 
       // Destroy window
       if (m_pWndProcStatus)
       {
         ::SetWindowLongPtr(m_hStatusBarWnd, GWLP_WNDPROC, (LPARAM)(WNDPROC)m_pWndProcStatus);
 
         m_pWndProcStatus = NULL;
       }
 
@@ skipping 705 matching lines @@
 {
   try
   {
     if (cCmds == 0) return E_INVALIDARG;
     if (prgCmds == 0) return E_POINTER;
 
     prgCmds[0].cmdf = OLECMDF_ENABLED;
   }
   catch (...)
   {
+    DEBUG_GENERAL(L"CPluginClass::QueryStatus - exception");
     return E_FAIL;
   }
   return S_OK;
 }
 
 HMENU CPluginClass::CreatePluginMenu(const std::wstring& url)
 {
   DEBUG_GENERAL("CreatePluginMenu");
   HINSTANCE hInstance = _AtlBaseModule.GetModuleInstance();
 
@@ skipping 266 matching lines @@
     }
     else
     {
       nFlags |= TPM_LEFTALIGN;
     }
 
     DisplayPluginMenu(hMenu, nIDCommand, pt, nFlags);
   }
   catch (...)
   {
-    return E_FAIL; //

[Oleksandr, 2016/01/04 10:46:13]

Nit: there was a comment intended here?

[Eric, 2016/01/04 16:44:24]

Yes. Added.

+    // Suppress exception, log only
+    DEBUG_GENERAL(L"CPluginClass::Exec - exception");
+    return E_FAIL;
   }
 
   return S_OK;
 }
 
 // Entry point
 LRESULT CALLBACK CPluginClass::NewStatusProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
 {
+  CPluginClass *pClass;
   try
   {
     // Find tab
-    CPluginClass *pClass = FindInstance(hWnd);
+    pClass = FindInstance(hWnd);
     if (!pClass)
     {
+      /*
+       * Race condition if reached.
+       * We did not unhook the window procedure for the status bar when the last BHO instance using it terminated.
+       * The next best thing is to call the system default window function.
+       */
       return DefWindowProc(hWnd, message, wParam, lParam);

[Eric, 2016/01/04 16:44:24]

Race condition here.

     }
 
     // Process message
     switch (message)
     {
     case SB_SIMPLE:
-    {
-      ShowWindow(pClass->m_hPaneWnd, !wParam);
-      break;
-    }
+      {
+        ShowWindow(pClass->m_hPaneWnd, !wParam);
+        break;
+      }
 
     case WM_SYSCOLORCHANGE:
-    {
-      pClass->UpdateTheme();
-      break;
-    }
+      {
+        pClass->UpdateTheme();
+        break;
+      }
 
     case SB_SETPARTS:
-    {
-      if (!lParam || !wParam || wParam > 30 || !IsWindow(pClass->m_hPaneWnd))
-      {
-        return CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, lParam);
-      }
-
-      WPARAM nParts = wParam;
-      if (STATUSBAR_PANE_NUMBER >= nParts)
-      {
-        return CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, lParam);
-      }
-
-      HLOCAL hLocal = LocalAlloc(LHND, sizeof(int) * (nParts + 1));
-      LPINT lpParts = (LPINT)LocalLock(hLocal);
-      memcpy(lpParts, (void*)lParam, wParam*sizeof(int));
-
-      for (unsigned i = 0; i < STATUSBAR_PANE_NUMBER; i++)
-      {
-        lpParts[i] -= pClass->m_nPaneWidth;
-      }
-      LRESULT hRet = CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, (LPARAM)lpParts);
-
-      AdblockPlus::Rectangle rcPane;
-      ::SendMessage(hWnd, SB_GETRECT, STATUSBAR_PANE_NUMBER, (LPARAM)&rcPane);
-
-      AdblockPlus::Rectangle rcClient;
-      ::GetClientRect(hWnd, &rcClient);
-
-      ::MoveWindow(
-        pClass->m_hPaneWnd,
-        lpParts[STATUSBAR_PANE_NUMBER] - pClass->m_nPaneWidth,
-        0,
-        pClass->m_nPaneWidth,
-        rcClient.Height(),
-        TRUE);
-
-      ::LocalFree(hLocal);
-
-
-      return hRet;
-    }
+      {
+        if (!lParam || !wParam || wParam > 30 || !IsWindow(pClass->m_hPaneWnd))
+        {
+          return CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, lParam);
+        }
+
+        WPARAM nParts = wParam;
+        if (STATUSBAR_PANE_NUMBER >= nParts)
+        {
+          return CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, lParam);
+        }
+
+        HLOCAL hLocal = LocalAlloc(LHND, sizeof(int) * (nParts + 1));
+        LPINT lpParts = (LPINT)LocalLock(hLocal);
+        memcpy(lpParts, (void*)lParam, wParam*sizeof(int));
+
+        for (unsigned i = 0; i < STATUSBAR_PANE_NUMBER; i++)
+        {
+          lpParts[i] -= pClass->m_nPaneWidth;
+        }
+        LRESULT hRet = CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, (LPARAM)lpParts);
+
+        AdblockPlus::Rectangle rcPane;
+        ::SendMessage(hWnd, SB_GETRECT, STATUSBAR_PANE_NUMBER, (LPARAM)&rcPane);
+
+        AdblockPlus::Rectangle rcClient;
+        ::GetClientRect(hWnd, &rcClient);
+
+        ::MoveWindow(
+          pClass->m_hPaneWnd,
+          lpParts[STATUSBAR_PANE_NUMBER] - pClass->m_nPaneWidth,
+          0,
+          pClass->m_nPaneWidth,
+          rcClient.Height(),
+          TRUE);
+
+        ::LocalFree(hLocal);
+        return hRet;
+      }
 
     default:
       break;
     }
-
-    LRESULT result = CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, lParam);
-
-
-    return result;
   }
   catch (...)
   {
-    return E_FAIL;

[Oleksandr, 2016/01/04 10:46:13]

I think we should call: return DefWindowProc(hWnd, message, wParam, lParam) here
instead. This is not a COM method so returning E_FAIL doesn't seem right.

[sergei, 2016/01/04 11:27:36]

It's better to use CallWindowProc instead of DefWindowProc here because we are
subclassing the window.

[Eric, 2016/01/04 16:44:24]

Sergei's right.

This observation also points out a defect on line 1287.

-  }
+    // Suppress exception. Fall through to default handler.
+    DEBUG_GENERAL(L"CPluginClass::NewStatusProc - exception");
+  }
+  return ::CallWindowProc(pClass->m_pWndProcStatus, hWnd, message, wParam, lParam);
 }
 
 
 HICON CPluginClass::GetStatusBarIcon(const std::wstring& url)
 {
   // use the disable icon as defualt, if the client doesn't exists
   HICON hIcon = GetIcon(ICON_PLUGIN_DEACTIVATED);
 
   CPluginTab* tab = GetTab(::GetCurrentThreadId());
   if (tab)
@@ skipping 23 matching lines @@
     // Find tab
     CPluginClass *pClass = FindInstance(GetParent(hWnd));
     if (!pClass)
     {
       return ::DefWindowProc(hWnd, message, wParam, lParam);
     }
 
     // Process message
     switch (message)
     {
-
     case WM_SETCURSOR:
-    {
-      ::SetCursor(::LoadCursor(NULL, IDC_ARROW));
-      return TRUE;
-    }
+      {
+        ::SetCursor(::LoadCursor(NULL, IDC_ARROW));
+        return TRUE;
+      }
     case WM_PAINT:
-    {
-      PAINTSTRUCT ps;
-      HDC hDC = ::BeginPaint(hWnd, &ps);
-
-      AdblockPlus::Rectangle rcClient;
-      ::GetClientRect(hWnd, &rcClient);
-
-      int nDrawEdge = 0;
-
-      // Old Windows background drawing
-      if (pClass->m_hTheme == NULL)
-      {
-        ::FillRect(hDC, &rcClient, (HBRUSH)(COLOR_BTNFACE + 1));
-        ::DrawEdge(hDC, &rcClient, BDR_RAISEDINNER, BF_LEFT);
-
-        nDrawEdge = 3;
-        rcClient.left += 3;
-
-        ::DrawEdge(hDC, &rcClient, BDR_SUNKENOUTER, BF_RECT);
-      }
-      // Themed background drawing
-      else
-      {
-        // Draw background
-        if (pfnDrawThemeBackground)
-        {
-          AdblockPlus::Rectangle rc = rcClient;
-          rc.right -= 2;
-          pfnDrawThemeBackground(pClass->m_hTheme, hDC, 0, 0, &rc, NULL);
-        }
-
-        // Copy separator picture to left side
-        int nHeight = rcClient.Height();
-        int nWidth = rcClient.Width() - 2;
-
-        for (int i = 0; i < 2; i++)
-        {
-          for (int j = 0; j < nHeight; j++)
+      {
+        PAINTSTRUCT ps;
+        HDC hDC = ::BeginPaint(hWnd, &ps);
+
+        AdblockPlus::Rectangle rcClient;
+        ::GetClientRect(hWnd, &rcClient);
+
+        int nDrawEdge = 0;
+
+        // Old Windows background drawing
+        if (pClass->m_hTheme == NULL)
+        {
+          ::FillRect(hDC, &rcClient, (HBRUSH)(COLOR_BTNFACE + 1));
+          ::DrawEdge(hDC, &rcClient, BDR_RAISEDINNER, BF_LEFT);
+
+          nDrawEdge = 3;
+          rcClient.left += 3;
+
+          ::DrawEdge(hDC, &rcClient, BDR_SUNKENOUTER, BF_RECT);
+        }
+        // Themed background drawing
+        else
+        {
+          // Draw background
+          if (pfnDrawThemeBackground)
           {
-            COLORREF clr = ::GetPixel(hDC, i + nWidth, j);
-
-            // Ignore black boxes (if source is obscured by other windows)
-            if (clr != -1 && (GetRValue(clr) > 8 || GetGValue(clr) > 8 || GetBValue(clr) > 8))
+            AdblockPlus::Rectangle rc = rcClient;
+            rc.right -= 2;
+            pfnDrawThemeBackground(pClass->m_hTheme, hDC, 0, 0, &rc, NULL);
+          }
+
+          // Copy separator picture to left side
+          int nHeight = rcClient.Height();
+          int nWidth = rcClient.Width() - 2;
+
+          for (int i = 0; i < 2; i++)
+          {
+            for (int j = 0; j < nHeight; j++)
             {
-              ::SetPixel(hDC, i, j, clr);
+              COLORREF clr = ::GetPixel(hDC, i + nWidth, j);
+
+              // Ignore black boxes (if source is obscured by other windows)
+              if (clr != -1 && (GetRValue(clr) > 8 || GetGValue(clr) > 8 || GetBValue(clr) > 8))
+              {
+                ::SetPixel(hDC, i, j, clr);
+              }
             }
           }
         }
-      }
-
-      // Draw icon
-      if (CPluginClient::GetInstance())
-      {
-        HICON hIcon = GetStatusBarIcon(pClass->GetTab()->GetDocumentUrl());
-
-        int offx = nDrawEdge;
-        if (hIcon)
-        {
-          //Get the RECT for the leftmost pane (the status text pane)
-          RECT rect;
-          BOOL rectRes = ::SendMessage(pClass->m_hStatusBarWnd, SB_GETRECT, 0, (LPARAM)&rect);
-          ::DrawIconEx(hDC, 0, rect.bottom - rect.top - iconHeight, hIcon, iconWidth, iconHeight, NULL, NULL, DI_NORMAL);
-          offx += iconWidth;
-        }
+
+        // Draw icon
+        if (CPluginClient::GetInstance())
+        {
+          HICON hIcon = GetStatusBarIcon(pClass->GetTab()->GetDocumentUrl());
+
+          int offx = nDrawEdge;
+          if (hIcon)
+          {
+            //Get the RECT for the leftmost pane (the status text pane)
+            RECT rect;
+            BOOL rectRes = ::SendMessage(pClass->m_hStatusBarWnd, SB_GETRECT, 0, (LPARAM)&rect);
+            ::DrawIconEx(hDC, 0, rect.bottom - rect.top - iconHeight, hIcon, iconWidth, iconHeight, NULL, NULL, DI_NORMAL);
+            offx += iconWidth;
+          }
 #ifdef _DEBUG
-        // Display version
-        HFONT hFont = (HFONT)::SendMessage(pClass->m_hStatusBarWnd, WM_GETFONT, 0, 0);
-        HGDIOBJ hOldFont = ::SelectObject(hDC, hFont);
-
-        AdblockPlus::Rectangle rcText = rcClient;
-        rcText.left += offx;
-        ::SetBkMode(hDC, TRANSPARENT);
-        ::DrawTextW(hDC, IEPLUGIN_VERSION, -1, &rcText, DT_WORD_ELLIPSIS | DT_LEFT | DT_SINGLELINE | DT_VCENTER);
-
-        ::SelectObject(hDC, hOldFont);
+          // Display version
+          HFONT hFont = (HFONT)::SendMessage(pClass->m_hStatusBarWnd, WM_GETFONT, 0, 0);
+          HGDIOBJ hOldFont = ::SelectObject(hDC, hFont);
+
+          AdblockPlus::Rectangle rcText = rcClient;
+          rcText.left += offx;
+          ::SetBkMode(hDC, TRANSPARENT);
+          ::DrawTextW(hDC, IEPLUGIN_VERSION, -1, &rcText, DT_WORD_ELLIPSIS | DT_LEFT | DT_SINGLELINE | DT_VCENTER);
+
+          ::SelectObject(hDC, hOldFont);
 #endif // _DEBUG
-      }
-
-      // Done!
-      EndPaint(hWnd, &ps);
-
-      return 0;
-    }
+        }
+
+        // Done!
+        EndPaint(hWnd, &ps);
+
+        return 0;
+      }
 
     case WM_LBUTTONUP:
     case WM_RBUTTONUP:
-    {
-      std::wstring url = pClass->GetBrowserUrl();
-      if (url != pClass->GetTab()->GetDocumentUrl())
-      {
-        pClass->GetTab()->SetDocumentUrl(url);
-      }
-
-      // Create menu
-      HMENU hMenu = pClass->CreatePluginMenu(url);
-      if (!hMenu)
-      {
-        return 0;
-      }
-
-      // Display menu
-      POINT pt;
-      ::GetCursorPos(&pt);
-
-      RECT rc;
-      ::GetWindowRect(hWnd, &rc);
-
-      if (rc.left >= 0 && rc.top >= 0)
-      {
-        pt.x = rc.left;
-        pt.y = rc.top;
-      }
-
-      pClass->DisplayPluginMenu(hMenu, -1, pt, TPM_LEFTALIGN | TPM_BOTTOMALIGN);
-    }
-    break;
+      {
+        std::wstring url = pClass->GetBrowserUrl();
+        if (url != pClass->GetTab()->GetDocumentUrl())
+        {
+          pClass->GetTab()->SetDocumentUrl(url);
+        }
+
+        // Create menu
+        HMENU hMenu = pClass->CreatePluginMenu(url);
+        if (!hMenu)
+        {
+          return 0;
+        }
+
+        // Display menu
+        POINT pt;
+        ::GetCursorPos(&pt);
+
+        RECT rc;
+        ::GetWindowRect(hWnd, &rc);
+
+        if (rc.left >= 0 && rc.top >= 0)
+        {
+          pt.x = rc.left;
+          pt.y = rc.top;
+        }
+
+        pClass->DisplayPluginMenu(hMenu, -1, pt, TPM_LEFTALIGN | TPM_BOTTOMALIGN);
+        break;
+      }
     case WM_DESTROY:
       break;
     case SC_CLOSE:
       break;
 
     case WM_UPDATEUISTATE:
-    {
-      CPluginTab* tab = GetTab(::GetCurrentThreadId());
-      if (tab)
-      {
-        tab->OnActivate();
+      {
+        CPluginTab* tab = GetTab(::GetCurrentThreadId());
+        if (tab)
+        {
+          tab->OnActivate();
+          RECT rect;
+          GetWindowRect(pClass->m_hPaneWnd, &rect);
+          pClass->notificationMessage.Move(rect.left + (rect.right - rect.left) / 2, rect.top + (rect.bottom - rect.top) / 2);
+        }
+        if (LOWORD(wParam) == UIS_CLEAR)
+        {
+          pClass->notificationMessage.Hide();
+        }
+        break;
+      }
+    case WM_WINDOWPOSCHANGING:
+      {
         RECT rect;
         GetWindowRect(pClass->m_hPaneWnd, &rect);
-        pClass->notificationMessage.Move(rect.left + (rect.right - rect.left) / 2, rect.top + (rect.bottom - rect.top) / 2);
-      }
-      if (LOWORD(wParam) == UIS_CLEAR)
-      {
-        pClass->notificationMessage.Hide();
-      }
-    }
-    break;
-    case WM_WINDOWPOSCHANGING:
-    {
-      RECT rect;
-      GetWindowRect(pClass->m_hPaneWnd, &rect);
-      if (pClass->notificationMessage.IsVisible())
-      {
-        pClass->notificationMessage.Move(rect.left + (rect.right - rect.left) / 2, rect.top + (rect.bottom - rect.top) / 2);
-      }
-    }
-    break;
+        if (pClass->notificationMessage.IsVisible())
+        {
+          pClass->notificationMessage.Move(rect.left + (rect.right - rect.left) / 2, rect.top + (rect.bottom - rect.top) / 2);
+        }
+        break;
+      }
     case WM_WINDOWPOSCHANGED:
-    {
-      WINDOWPOS* wndPos = reinterpret_cast<WINDOWPOS*>(lParam);
-      if (wndPos->flags & SWP_HIDEWINDOW)
-      {
-        pClass->notificationMessage.Hide();
-      }
-    }
-    break;
+      {
+        WINDOWPOS* wndPos = reinterpret_cast<WINDOWPOS*>(lParam);
+        if (wndPos->flags & SWP_HIDEWINDOW)
+        {
+          pClass->notificationMessage.Hide();
+        }
+        break;
+      }
     case WM_ALREADY_UP_TO_DATE:
-    {
-      Dictionary* dictionary = Dictionary::GetInstance();
-      std::wstring upToDateText = dictionary->Lookup("updater", "update-already-up-to-date-text");
-      std::wstring upToDateTitle = dictionary->Lookup("updater", "update-already-up-to-date-title");
-      pClass->notificationMessage.SetTextAndIcon(upToDateText, upToDateTitle, TTI_INFO);
-    }
-    break;
+      {
+        Dictionary* dictionary = Dictionary::GetInstance();
+        std::wstring upToDateText = dictionary->Lookup("updater", "update-already-up-to-date-text");
+        std::wstring upToDateTitle = dictionary->Lookup("updater", "update-already-up-to-date-title");
+        pClass->notificationMessage.SetTextAndIcon(upToDateText, upToDateTitle, TTI_INFO);
+        break;
+      }
     case WM_UPDATE_CHECK_ERROR:
-    {
-      Dictionary* dictionary = Dictionary::GetInstance();
-      std::wstring errorText = dictionary->Lookup("updater", "update-error-text");
-      std::wstring errorTitle = dictionary->Lookup("updater", "update-error-title");
-      pClass->notificationMessage.SetTextAndIcon(errorText, errorText, TTI_ERROR);
-    }
-    break;
+      {
+        Dictionary* dictionary = Dictionary::GetInstance();
+        std::wstring errorText = dictionary->Lookup("updater", "update-error-text");
+        std::wstring errorTitle = dictionary->Lookup("updater", "update-error-title");
+        pClass->notificationMessage.SetTextAndIcon(errorText, errorText, TTI_ERROR);
+        break;
+      }
     case WM_DOWNLOADING_UPDATE:
-    {
-      Dictionary* dictionary = Dictionary::GetInstance();
-      std::wstring downloadingText = dictionary->Lookup("updater", "downloading-update-text");
-      std::wstring downloadingTitle = dictionary->Lookup("updater", "downloading-update-title");
-      pClass->notificationMessage.SetTextAndIcon(downloadingText, downloadingTitle, TTI_INFO);
-    }
-    break;
-    }
-
-    return DefWindowProc(hWnd, message, wParam, lParam);
+      {
+        Dictionary* dictionary = Dictionary::GetInstance();
+        std::wstring downloadingText = dictionary->Lookup("updater", "downloading-update-text");
+        std::wstring downloadingTitle = dictionary->Lookup("updater", "downloading-update-title");
+        pClass->notificationMessage.SetTextAndIcon(downloadingText, downloadingTitle, TTI_INFO);
+        break;
+      }
+    }
   }
   catch (...)
   {
-    return E_FAIL;

[Oleksandr, 2016/01/04 10:46:13]

Same here. I think we should do 'return DefWindowProc(hWnd, message, wParam,
lParam);' instead.

[Eric, 2016/01/04 16:44:24]

Done.

Replace with a comment. Moved call to 'DefWindowProc' to the end, outside the
'try' statement, since it doesn't throw.

-  }
+    // Suppress exception. Fall through to default handler.
+    DEBUG_GENERAL(L"CPluginClass::PaneWindowProc - exception");
+  }
+  return ::DefWindowProc(hWnd, message, wParam, lParam);
 }
 
 
 void CPluginClass::UpdateStatusBar()
 {
   DEBUG_GENERAL("*** Updating statusbar")
   if (m_hPaneWnd == NULL)
   {
     CreateStatusBarPane();
   }
@@ skipping 48 matching lines @@
   s_criticalSectionLocal.Unlock();
 
   return icon;
 }
 
 ATOM CPluginClass::GetAtomPaneClass()
 {
   return s_atomPaneClass;
 }