Microsoft KB Archive/169928

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Article ID: 169928

Article Last Modified on 7/20/2005



APPLIES TO

  • Microsoft Visual SourceSafe 5.0 Standard Edition
  • Microsoft Visual SourceSafe 6.0 Standard Edition



This article was previously published under Q169928

SUMMARY

This article contains sample C++ code along with an explanation of how to get a pointer to a SourceSafe database object and execute the Open method to start a session with a SourceSafe database.

MORE INFORMATION

Visual SourceSafe must be registered before you can use its OLE Automation Model. The following CLSID should be found in HKEY_CLASSES_ROOT/CLSID: {783CD4E4-9D54-11CF-B8EE-00608CC9A71F}. Registration occurs by default when you install the SourceSafe Client.

To work with the objects in the SourceSafe OLE Model, first you must have access to a VSSDatabase object, and call its Open method.

  1. Use the CLSIDFromProgID function to obtain the CLSID from the registry as shown in the example below.
  2. Call CoGetClassObject with the CLSID obtained in Step 1 asking for a pointer to the IClassFactory Interface.
  3. Use the CreateInstance Method from the IClassFactory interface to obtain a pointer to an IVSSDatabase object.
  4. Call the open method of the IVSSDatabase object passing in the path to the srcsafe.ini, a valid User Name and password as BSTRs.

Note You can use the SysAllocString function to convert an OLECHAR* to a BSTR.

Use the MultiByteToWide function to convert an LPSTR to OLECHAR* as shown in the following code fragment:

   if((x=MultiByteToWideChar(CP_ACP,0,path,-1,svalue,0)) != 1)
   {

     svalue = (OLECHAR*)malloc( x*sizeof(wchar_t) );
     if(MultiByteToWideChar(CP_ACP, 0, path, -1, svalue, x ) == 0)
       MessageBox( NULL, "Error in Conversion", "Multibytetowide", MB_OK );

   }
   else

     svalue = L"";
                

MultiByteToWide counts the characters and determines the size of the buffer needed to hold the BSTR. The appropriate size buffer is then allocated and the conversion is done. In the example above svalue is an OLECHAR*, and path is an LPSTR.

Sample code

The following sample code demonstrates how to open a SourceSafe database as described above:

   // Be sure to link with the following libraries:
   // user32.lib uuid.lib oleaut32.lib ole32.lib
   #define INITGUID
   #include <windows.h>
   #include <ocidl.h>
   #include "ssauto.h"

   int main () {
     CLSID clsid;
     IClassFactory *pClf;
     IVSSDatabase *pVdb;
     BSTR bstrPath = SysAllocString(L"c:\\VSSclient\\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))
           {
             //Database Successfully Opened!
             //Add code here to use the open database.
           }
           pVdb->Release();
         }
         pClf->Release();
       }
     }
     CoUninitialize();

     SysFreeString(bstrPath);
     SysFreeString(bstrUName);
     SysFreeString(bstrUPass);
     return 0;

   }
                

REFERENCES

MSDN Library: SysAllocString; SysFreeString; CLSIDFromProgID; IClassFactory; CoGetClassObject; Visual SourceSafe OLE Automation

The header file ssauto.h can be downloaded from the following Web site:

Keywords: kbhowto KB169928