IVssComponentEx::GetPrepareForBackupFailureMsg method (vswriter.h)

Returns the PrepareForBackup failure message string that a writer has set for a given component.

Both writers and requesters can call this method.

Syntax

HRESULT GetPrepareForBackupFailureMsg(
 [out] BSTR *pbstrFailureMsg
);

Parameters

[out] pbstrFailureMsg

A pointer to a null-terminated wide character string containing the failure message that describes an error that occurred while processing a PrepareForBackup event.

Return value

The following are the valid return codes for this method.

Remarks

The caller is responsible for freeing the string that the pbstrFailureMsg parameter points to by calling the SysFreeString function.

Examples

#include <windows.h>
#include "vss.h"
#include "vsmgmt.h"

#define CHKARG_ASSERT(EXPR) 
do
{
 if(! ( EXPR ) ) 
 { 
 assert(FALSE); 
 hr = E_INVALIDARG; 
 goto exit; 
 } 
}
while ( FALSE, FALSE );

#define CHK(HR) 
do
{
 hr = ( HR ) ; 
 if(FAILED(HR)) 
 { 
 hr = HR; 
 goto exit; 
 } 
}
while ( FALSE, FALSE ); 

STDMETHODIMP CheckAsrBackupErrorMsg
(
 IVssBackupComponents *pBackup,
 const WCHAR *pwszWriterName
)
{
 CComPtr<IVssWriterComponentsExt> spWriter;
 CComPtr<IVssComponent> spComponent;
 CComPtr<IVssComponentEx> spComponentEx;
 UINT cWriterComponents = 0;
 UINT iWriterComponent = 0;
 UINT cComponents = 0;
 UINT iComponent = 0;
 VSS_ID idWriter;
 VSS_ID idInstance;
 CComBSTR bstrFailureMsg;
 HRESULT hr = S_OK;
 CHKARG_ASSERT( pBackup );
 CHKARG_ASSERT( pwszWriterName );

 CHK( pBackup->GetWriterComponentsCount( &cWriterComponents ) );

 for( iWriterComponent = 0; iWriterComponent < cWriterComponents; iWriterComponent++ )
 {
 spWriter.Release();
 CHK( pBackup->GetWriterComponents( iWriterComponent, &spWriter ) );
 CHK( spWriter->GetWriterInfo(&idInstance, &idWriter) );
 if( idWriter != c_ASRWriterId )
 {
 continue;
 }
 
 CHK( spWriter->GetComponentCount(&cComponents) );
 for( iComponent = 0; iComponent < cComponents; iComponent++ )
 {
 spComponent.Release();
 spComponentEx.Release();
 CHK( spWriter->GetComponent(iComponent, &spComponent) );
 CHK( spComponent->QueryInterface(__uuidof(IVssComponentEx), (void**)&spComponentEx) );

 bstrFailureMsg.Empty();
 CHK( spComponentEx->GetPrepareForBackupFailureMsg(&bstrFailureMsg) );

 if( ::SysStringLen(bstrFailureMsg) != 0 )
 {
 // Write into the event log.
 Log_SPP_ERROR_WRITER( &ft, __LINE__, pwszWriterName, bstrFailureMsg );

 // The ASR writer writes the same message to all components. 
 // Log the message once.
 break;
 }
 }
 }

exit:
 return hr;
}

Requirements

See also

CVssWriter::OnPrepareBackup

IVssComponentEx

IVssComponentEx::SetPrepareForBackupFailureMsg