IDebugBreakpointChecksumRequest2::GetChecksum

Note

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Retrieves the document checksum for a breakpoint request given the unique identifier of the checksum algorithm to use.

Syntax

HRESULT GetChecksum(   
   REFGUID        guidAlgorithm,  
   CHECKSUM_DATA *pChecksumData  
);  

public int GetChecksum(   
   ref Guid               guidAlgorithm,  
   out enum_CHECKSUM_DATA pChecksumData  
);  

Parameters

guidAlgorithm
[in] Unique identifier of the checksum algorithm.

pChecksumData
[out] Document checksum for the breakpoint request.

Return Value

If successful, returns S_OK; otherwise, returns an error code.

Example

The following example shows a function that checks whether the checksum of a document, which is about to be bound, matches one from the UI.

bool CDebugProgram::DoChecksumsMatch(CDebugPendingBreakpoint *pPending, CDebugCodeContext *pContext)  
{  
    bool fRet = false;  
    HRESULT hRes;  
  
    // Get the checksum for the document we are about to bind to from the pdb side  
    GUID guidAlgorithmId;  
    BYTE *pChecksum = NULL;  
    ULONG cNumBytes = 0;  
  
    hRes = pContext->GetDocumentChecksumAndAlgorithmId(&guidAlgorithmId, &pChecksum, &cNumBytes);  
  
    if ( S_OK == hRes )  
    {  
        // Get checksum data for the document from the UI (request) side  
        CComPtr<IDebugBreakpointChecksumRequest2> pChecksumRequest;  
  
        hRes = pPending->GetChecksumRequest(&pChecksumRequest);  
  
        if ( S_OK == hRes )  
        {  
            CHECKSUM_DATA data;  
  
            hRes = pChecksumRequest->GetChecksum(guidAlgorithmId, &data);  
  
            if ( S_OK == hRes )  
            {  
                if ( data.ByteCount == cNumBytes && memcmp(data.pBytes, pChecksum, cNumBytes) == 0 )  
                    fRet = true;  
                else  
                    fRet = false;  
  
                // Free up data allocated for checksum data  
                CoTaskMemFree(data.pBytes);  
            }  
            else  
                fRet = true; // checksums not available - user disabed checksums  
        }  
        else  
            fRet = true; // we couldn't get checksum from UI - default to past behavior  
  
        // free up space allocated for checksum from pdb  
        CoTaskMemFree(pChecksum);  
    }  
    else  
        fRet = true; // we don't have a checksum to compare with.  
  
    return ( fRet );  
}  

See Also

IDebugBreakpointChecksumRequest2