bits and bytes

Convert a VB6 project to VB.net Visual Studio 2010

Sep 202011

Are you having trouble converting VB6 project to VB.net Visual Studio 2010. Well just to be frank you should have long back converted this VB6 project of yours to VB.net. VB6 is ancient and just because your code works doesn’t mean that you won’t migrate it to a newer platform. In my opinion let your customers use the VB6 project of yours while you in the background should have converted a copy of it to VB.net. Now you might say it’s too much work… well how about it now.

Just to be clear Visual Studio 2010 does NOT inherently support converting VB6 project to VB.net 2010. When I force a conversion (via project open dialog) I get the following error dialog…

VB6 to VB.net 2010 - Conversion Error

Recently Mr. X asked me this question so I sent him an email with the steps on converting a VB6 project to VB.net Visual Studio 2010. So here are the steps (straight from the email I sent to the customer…)

Make sure VB 6.0 with SP 6.0 installed on the machine.
Make sure that all the referenced components (ActiveX dll, OCX) for the VB 6.0 application is available on the machine.
Open the VB 6.0 project in VB 6.0 IDE and make sure that it opens fine. Build the project and make sure that the application executes without any errors.
Run the Upgrade assessment tool on the visual basic 6 project:
(Old one) http://www.microsoft.com/downloads/details.aspx?FamilyId=10C491A2-FC67-4509-BC10-60C5C039A272&displaylang=en
(New one) http://www.artinsoft.com/visual-basic-upgrade-assessment-tool.aspx
Keep a local copy of the VB 6.0 project
There is no direct wizard conversion in Visual Studio 2010. You have to first use the conversion wizard available in Visual Studio 2005/2008 to convert to VB.net and then convert the same to Visual Studio 2010. As you don’t have Visual Studio 2008, you can download free version from following link.
http://www.microsoft.com/visualstudio/en-us/products/2008-editions/express
Once you are done with the conversion you can uninstall Visual Studio 2008 express edition.
Also you can download a free guide which contains information about Upgrading Visual Basic 6.0 Applications to Visual Basic .NET and Visual Basic 2005 (Its bit old but it will give useful insights as and when you are migrating source code to .net).
http://www.microsoft.com/downloads/details.aspx?FamilyId=7C3FE0A9-CBED-485F-BFD5-847FB68F785D&displaylang=en

A general note:

As per the upgrade guide, the effect of the changes and subtle differences in Visual Basic .NET is that, unlike previous versions of Visual Basic, most real-world projects cannot be upgraded 100 percent automatically. To understand why, consider that for a 100 percent upgrade there has to be a one-to-one correlation between every element of Visual Basic 6 and a corresponding element in Visual Basic .NET. Unfortunately, this correlation does not exist. The upgrade process is closer to 95 percent, meaning that the Visual Basic .NET Upgrade Wizard upgrades 95 percent of your application, and you modify 5 percent of the application to get it working. What does 5 percent mean? If it took you 100 days to write the original Visual Basic 6 application, you might expect to take 5 days to upgrade it. This number is not set in stone-some applications are easier to upgrade than others, and the experience of the person doing the upgrade is an important factor. To prepare yourself, make sure you familiarize yourself with Part IV of the upgrade guide. It discusses how to design your Visual Basic 6 applications to make the upgrade process much smoother.

Microsoft Visual Basic 6.0 Migration Resource Center
http://msdn.microsoft.com/hi-in/vbrun/ms788233(en-us).aspx

C++11 Features in Visual C++ vNext

C++, VC++, STL No Responses »

Sep 142011

There’s a new C++ Standard and a new version of Visual C++, and it’s time to reveal those features. Read more here…

http://blogs.msdn.com/b/vcblog/archive/2011/09/12/10209291.aspx

A preview of Windows 8

Windows No Responses »

Sep 132011

Enjoy maadi:

http://www.buildwindows.com/

Automatically launching CDB to take a dump of a native/managed crash

Debugging No Responses »

Sep 132011

Found a nice article which describes how to take native/managed crash dumps automatically using CDB as soon as a crash takes place. We know that for CLR 2.0 we’ve got to configure crash handler settings at two places in the registry for a native and managed application.

For native

HKLM\Software\Microsoft\Windows NT\Current Version\AeDebug\Debugger
HKLM\Software\Microsoft\Windows NT\Current Version\AeDebug\Auto

For managed

HKLM\Software\Microsoft\.NETFramework\DbgManagedDebugger
HKLM\Software\Microsoft\.NETFramework\DbgJITDebugLaunchSetting

This article from MSDN explains in detail on how to configure registry entries to take automatic crash dumps using CDB…

http://blogs.msdn.com/b/clrteam/archive/2009/10/15/automatically-capturing-a-dump-when-a-process-crashes.aspx

How to enable or disable Just in Time Debugging (JIT)

.net, C#, VB No Responses »

Sep 062011

Read the following article in MSDN:

http://msdn.microsoft.com/en-us/library/5hs4b7a6.aspx

The easiest way to disable JIT debugger is via the Tools->Options dialog in Visual Studio. For other options read the article.

Enable/Disable Just in Time Debugger in Visual Studio Options dialog

Permalink .net, ATL, C Programming, C#, C++, VC++, COM, Debugging, MFC, STL, VB, Windows API No Responses »

Mar 222011

ATL 9.0 displayed in the middle of an Activex control

ATL, COM No Responses »

Mar 172011

Recently a customer of mine faced this issue. So he had an ActiveX control and when displaying the ActiveX control in browser a string is displayed right in the middle of the control: “ATL 9.0″.

So this issue happens because you didn’t override CComControlBase::OnDraw function. The default code for CComControlBase::OnDraw looks like the following…

HRESULT CComControlBase::YourClassName::OnDraw(_In_ ATL_DRAWINFO& di)
{
  ::SetTextAlign(di.hdcDraw, TA_CENTER|TA_BASELINE);
  LPCTSTR pszText = _T("ATL ") _T(_ATL_VER_RBLD); // "ATL 9.0"
  ::TextOut(di.hdcDraw,
            di.prcBounds->left + (di.prcBounds->right - di.prcBounds->left) / 2,
            di.prcBounds->top + (di.prcBounds->bottom - di.prcBounds->top) / 2,
            pszText,
            lstrlen(pszText)); 
   return S_OK;
}

MSDN documentation for CComControlBase::OnDraw function confirms this behavior. Quote…

The wizard’s default OnDraw draws a rectangle with the label “ATL 8.0″.

The solution for this is to override CComControlBase::OnDraw function in your derived class and provide your own drawing or just return S_OK.

Dump file

Debugging, Windows 1 Response »

Mar 152011

This blog entry deals with user mode dumps only. Kernel mode dump files is not dealt with here but should be quite similar.

Define dump file

It is the memory snapshot of a process. The dump file saves all information pertaining to a process. The information include, loaded modules/dlls, handles, executing threads and other stuffs. Optionally we can include heap information.

How to open a dump file?

Dump files can be opened in a debugger as you would normally open a process or attach to a process. All debuggers provide options for opening a dump file. Here is the menu option in WinDbg which opens a dump file…

Open dump file option in windbg

A similar but, kinda hidden, version of open dump file option in Visual Studio, its not so visible unless you dig a bit. See below screenshot…

How to create a dump file?

A quick option which is quite is limited is to use the task manager “Create Dump File” option. Which looks like…

: Task manager create dump file option

With windbg use the .dump /ma D:\DumpFile.dmp command. With visual studio you can attach to a process and use Debug->Save dump as or while you are debugging use Debug->Save dump as.

Another tool that comes along with ”Debugging tools for windows” is ADPlus, a VBScript based tool, which automates the process of creating a dump file. This tool works by using cdb.exe (console debugger) command line options. Very powerful. I’ll blog about the tool in another post.

Limitations of dump files

You cannot execute the dump file, just like you would normally do with a process, or set breakpoints; a dump is a ‘snapshot’ of a process at a particular point of time. So all stuff in memory up till that particular point of time will be available but not after that particular point of time. Also if you have a wrong dump file then you could end up wasting time, so in order to prevent such cases we have tools like ADPlus which when setup properly automates the process of capturing dumps.

Different kinds of dumps

Crash dump – automatically taken during a crash
Hang dump – automatically taken (using tools like ADPlus)
High CPU dump – automatically taken (using tools like ADPlus)

Dump file tips in windbg

I normally execute the following command in WinDbg: !analyze -v. This command gives a summary of the stuff in dump file. So it shows you the stack of the thread in which the exception occurred.
Also when you open a dump file in WinDbg you’ll get a brief summary of the exception that occurred and also a view of the registers.
If you have a hang dump or a high CPU dump you will love the following command: !analyze -hang. This shows us the name of the function which is eating up most of CPU time.
You will love the command !runaway which shows the excecution time for each thread, so this way you can identify the thread that’s taking most of CPU time.
To know the type of dump file you are working on enter “||” into WinDbg. This command will tell you whether you are dealing with a full dump or a mini dump. A sample output on a dump of MsPaint.exe looks like…
0 Full memory user mini dump: D:\MsPaint.dmp
To know the name and id of the process for which this dump was made use the single pipe command “|”. Sample output looks like…
0 id: 11e4 examine name: C:\Windows\System32\mspaint.exe
.ecxr gives you exception record along with registers display.
.lastevent shows you the last exception that occurred.
You can create a mini dump out of a full dump by executing a .dump filename command on the existing dump.
To view last error status of all threads use !gle -all
Its very important to have the correct pdb files. Public symbol path and downstream store path should be set in WinDbg or by using _NT_SYMBOL_PATH environment variable. This is how mine looks -> SRV*C:\DebugSymbols*http://msdl.microsoft.com/download/symbols
Don’t forget you are doing “post mortem” debugging. The dead doesn’t walk and talk.
~* kpn shows stack of all threads
!locks displays locks held by threads
!lmvm ModuleName display information about a module. !lmvm User32 display information about user32.dll.
- lm sm display all modules loaded/unloaded in sorted order, ’when’ the dump was taken.
- lm or lmvi display all modules loaded/unloaded in their load/unload order
dt command displays type information of a type passed in.
dv command displays all local variables

x to examine a symbol. For e.g. to see all symbols in kernel32 starting LoadLibrary use following command: x kernel32!LoadLibrary*. The output looks like…

00000000`77906640 kernel32!LoadLibraryExWStub =
00000000`778fe3b0 kernel32!LoadLibraryExAStub =
00000000`77907058 kernel32!LoadLibraryExA =
00000000`77906f80 kernel32!LoadLibraryW =
00000000`77907070 kernel32!LoadLibraryA =
00000000`77906634 kernel32!LoadLibraryExW =

Conclusion

Have fun debugging dump files and help others too. Spread word about this article. If you’ve got comments let me know.

New Book “Parallel Programming with Microsoft Visual C++” now available!

Books, C++, VC++, Parallel Programming No Responses »

Mar 102011

Note: Quote from a mail that I received.

Last fall we shipped Parallel Programming for Microsoft .NET and immediately started working on a companion version of the book for C++ programmers. I’m very happy to announce that Parallel Programming with
Microsoft Visual C++: Design patterns for Decomposition, and Coordination on Multicore Architectures is now available!

Book on native parallel programming

Where Can I Get The Book?

The content is available right now on MSDN Library: Parallel Programming with Microsoft Visual C++. The layout isn’t quite as nice as the printed book but all the content is there. The publication coincides with the release of Visual Studio SP1 giving us some significant new content to show to developers and help them be successful with the latest parallel programming features in Visual Studio.

The printed book is available for pre-order from O’Reilly:

Parallel Programming with Microsoft® Visual C++

The eBook will also be available for download from O’Reilly and Safari Books Online shortly. Expect to see it on Amazon real soon! When I have hardcopies I’ll be making them available as I did with the .NET book

What’s In The Book?

The book describes six key patterns for data and task parallelism and how to implement them using the Parallel Patterns Library and Asynchronous Agents Library, which shipped with Visual Studio 2010.

Parallel programming patterns

The book also includes additional material. Appendices on how the Task Scheduler and Resource Manager work and how to use the Visual Studio profiler and debugger to understand your application’s performance. It also include an appendix on Microsoft’s technology roadmap for technical computing, that sets the book in a larger context.

How About Code Samples?

Accompanying the book are code samples for each chapter. This includes small code samples showing how to use each feature of the Task Parallel Library and a larger example for each chapter setting the pattern in a larger context. You can download them from our Parallel Patterns CodePlex site. You can also download answers to the questions at the end of each chapter from CodePlex.

Acknowledgements

Once again I’d like to thank my co-author, Colin Campbell and the team of editors and production specialists who did all the real work. I’d also like to thank the countless people who provided feedback, helped with samples and reviewed material. They are all acknowledged in the book.

PickIconDlg function explained

Windows API No Responses »

Mar 052011

In windows if you ever changed the icon of a shortcut then you’ll know what the API PickIconDlg does. Basically this function will let you select any icon embedded as a resource in a .dll or .exe file for use in your application. Just select in the dialog the icon that you like and click ok. Here is a shot of the dialog, in my case I’ve given devenv.exe and this is how it looks for me…

PickIcon dialog screenshot

So the API for invoking the API is as follows…

int Index = 2;
const DWORD BuffSize = MAX_PATH*2;
TCHAR Path[BuffSize] = {_T("C:\\Program Files (x86)\\Microsoft Visual Studio 10.0\\Common7\\IDE\\devenv.exe")};
const int Sel = PickIconDlg(GetSafeHwnd(), Path, BuffSize, &Index);
if(Sel)
{
 // The hinst parameter is assumed to have been initialized earlier.
 HMODULE hMod = ::LoadLibrary(Path);
 m_hIcon = ExtractIcon(hMod, Path, Index);
 // After some work destroy the icon
 FreeLibrary(hMod);
}

// Set the icon for this dialog using above extracted icon
SetIcon(m_hIcon, TRUE); // Set big icon
SetIcon(m_hIcon, FALSE); // Set small icon

Now see my dialog titlebar after executing this code snippet…