BUG: ATL Registrar Code Does Not Handle DBCS Correctly (239909)


The information in this article applies to:

  • The Microsoft Active Template Library (ATL) 3.0
  • The Microsoft Active Template Library (ATL) 2.0
  • The Microsoft Active Template Library (ATL) 2.1
This article was previously published under Q239909

SYMPTOMS

When you register an ATL object on a system that uses a double-byte character set (DBCS), ATL might put garbage characters in the registry entry for the object.

CAUSE

In the AddString function in ATL 3.0 in file StatReg.h, lpszT++ is used to walk a character buffer, and then characters are added at that position. If the buffer contains DBCS characters, this will cause corruption in the string because ATL fails to take into account the 2-byte characters.

The function CParseBuffer::AddString in ATL 2.0 and 2.1 in file StatReg.cpp has the same problem.

RESOLUTION

Steps to Fix the Problem for ATL 2.0 and 2.1

  1. In StatReg.cpp, find the CParseBuffer::AddString function.
  2. On line 8 of the AddString function, change
    lpszT++
    to:
    lpszT = CharNext(lpszT);
  3. Save StatReg.cpp so the changes will be retained.
  4. Rebuild the project with a Release MinDependency build configuration. (If you do not build with this option, you would have to add _ATL_STATIC_REGISTRY to the preprocessor definitions of the project so ATL would add the registration code to your project. You would also have to remove the _ATL_DLL preprocessor option. You do not have to add _ATL_STATIC_REGISTRY if you are building with a Release MinDependency build configuration because it is already defined.)
  5. Rebuild the project.

By using this procedure, the registration code for any COM objects in the project will be statically linked and will not use the incorrect code in Atl.dll. This will also add about 5 KB to the size of the executable or DLL.

Steps to Fix the Problem for ATL 3.0

  1. In StatReg.h, find the AddString function.
  2. On line 8 of the AddString function, change 
    lpszT++
    to:
    CharNext(lpszT)
  3. Save StatReg.h so the changes will be retained.
  4. Rebuild the project with a Release MinDependency build configuration. (If you do not build with this option, you would have to add _ATL_STATIC_REGISTRY to the preprocessor definitions of the project so ATL would add the registration code to your project. You would also have to remove the _ATL_DLL preprocessor option. You do not have to add _ATL_STATIC_REGISTRY if you are building with a Release MinDependency build configuration because it is already defined.)
  5. Rebuild the project.

By using the above steps, the registration code for any COM objects in the project will be statically linked and will not use the incorrect code in ATL.DLL. This will add about 10 KB to the size of the executable or DLL.

STATUS

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

Steps to Reproduce Behavior

  1. Create an ATL object.
  2. Register the object on a system that uses DBCS, such as the Japanese version of Windows NT 4.0.
  3. Use Regedt32 to view the key under HKEY_CLASSES_ROOT that your object added to see if the name is correct.
Modification Type:MajorLast Reviewed:9/23/2003
Keywords:kbBug kbpending kbRegistry KB239909
©2003 Microsoft Corporation. All rights reserved.