BUG: get_Version returns S_OK even if the version does not exist (248194)


The information in this article applies to:

  • Microsoft Visual SourceSafe for Windows 5.0
  • Microsoft Visual SourceSafe for Windows 6.0
This article was previously published under Q248194

SYMPTOMS

When trying to get a specific version of a file or project, the get_Version function returns successfully and has a valid item even if that item does not exist in the database.

RESOLUTION

Instead of checking the HRESULT or whether the IVSSItem is not null, check the get_VersionNumber after calling get_Version. Compare the version numbers to make sure the version is valid. For example, place the following code inside the pVdb->get_VSSItem if statement: 
// Used to store the latest version number of the item
long originalnumber, num;

// Store the latest version number of the item
vssi->get_VersionNumber(&originalnumber);

// Get the version at the label (this label will fail)
CComVariant varLabel = -51;
vssi->get_Version(varLabel, &vx);

// Get the version number of the returned item
vx->get_VersionNumber(&num);

// Compare the versions and see if the item is valid
if ( num > 0 && num <= originalnumber )
   printf("Valid label.");

// Release the item
vx->Release();

STATUS

Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the "Applies to" section.

MORE INFORMATION

Steps to reproduce the behavior

  1. Create a Win32 Console Application in Microsoft Visual C++.
  2. Add the following code to the project.

    Note This is the same code as in the following Microsoft Knowledge Base Article:

    169927 How to get history using SourceSafe OLE automation in C++ 

    #include <atlbase.h>
#include <comdef.h>
#include <initguid.h>
#include "ssauto.h"

int main ()
{
   CLSID clsid;
   IClassFactory *pClf;
   IVSSDatabase *pVdb;
   BSTR bstrPath = SysAllocString(L"c:\\Program Files\\Microsoft Visual Studio\\Common\\VSS\\srcsafe.ini");
   BSTR bstrUName = SysAllocString(L"guest");
   BSTR bstrUPass = SysAllocString(L"");

   CoInitialize(0);
   if(S_OK == CLSIDFromProgID(L"SourceSafe", &clsid ))
   {
      if(S_OK == CoGetClassObject( clsid, CLSCTX_ALL, NULL,
         IID_IClassFactory, (void**)&pClf ))
      {
         if(S_OK == pClf->CreateInstance( NULL, IID_IVSSDatabase,
            (void **) &pVdb ))
         {
            if(S_OK == pVdb->Open(bstrPath, bstrUName, bstrUPass))
            {
               // Get the root project
               BSTR bstrName = SysAllocString(L"$/");
               IVSSItem *vx;
               IVSSItem *vssi;

               if( S_OK == pVdb->get_VSSItem(bstrName, FALSE, &vssi) )
               {
                  // Get the version at the label (this label should fail)
                  CComVariant varLabel = -51;
                  if( S_OK == vssi->get_Version(varLabel, &vx) )
                  {
                     // This prints out even though the label in invalid
                     printf("Should not be here.");

                     vx->Release();
                  }

                  vssi->Release();
               }

               SysFreeString(bstrName);
            }

            pVdb->Release();
         }

         pClf->Release();
      }
   }

   CoUninitialize();

   SysFreeString(bstrPath);
   SysFreeString(bstrUName);
   SysFreeString(bstrUPass);
   return 0;
}
  3. Download and add the ssauto.h header file that is used to integrate with Visual SourceSafe from the following Microsoft Web site:

    http://www.msdn.microsoft.com/vstudio/previous/ssafe/downloads/samples/

  4. Run the program.

REFERENCES

For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

196197 You receive an error message when you get a file from a project label by using OLE automation

Modification Type:MajorLast Reviewed:7/20/2005
Keywords:kbAutomation kbBug kbnofix KB248194 kbAudDeveloper
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