Implement GetSymbolStoreFileName

[tmat]

Tracking TODO in source

[KirillOsenkov]

Do you have any tips on how this should be implemented?

symreader-portable/src/Microsoft.DiaSymReader.PortablePdb/SymReader.cs

Line 685 in 7380d91

public int GetSymbolStoreFileName(int bufferLength, out int count, [In, MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 0), Out]char[] name)

Just return the full path to the .dll file?

[tmat]

Pretty much reverse-engineer native SymReader and do what it does.

[KirillOsenkov]

Do you have a pointer to the native source of GetSymbolStoreFileName? Where can I find it?

This exception would be nice to fix soon, I'm running into this quite a bit.

[KirillOsenkov]

Looks like it's just returning the full path to the .pdb file??

HRESULT
SymReader::GetSymbolStoreFileName(
    ULONG32 cchName,
    _Out_ ULONG32 *pcchName,
    _Out_capcount_(cchName) WCHAR szName[]
)
{
    HRESULT hr = S_OK;
    CDiaString dszName;
    ULONG32 tmpcchName;

    METHOD_ENTRY( SymReader::GetSymbolStoreFileName);

    IfFalseGo( m_cDiawr > 0, E_FAIL );

    IfFailGo( m_rgDiawr[0]->GetPdbName( &dszName ) );

    tmpcchName = (ULONG32)(wcslen(dszName) + 1);

    if (cchName)
    {
        if ( tmpcchName <= cchName )
        {
            if (pcchName)
                *pcchName = tmpcchName;
            wcsncpy_s( szName, cchName, dszName, tmpcchName );
        }
        else
        {
            if (pcchName)
                *pcchName = 0;
            hr = HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
        }
    }
    else
    {
        if (pcchName)
            *pcchName = tmpcchName;
    }

Error:

    METHOD_EXIT( SymReader::GetSymbolStoreFileName, hr );

    return hr;
}

[KirillOsenkov]

CDiaWrapper.GetPdbName does this:

HRESULT
CDiaWrapper::GetPdbName(
    _Deref_out_z_ wchar_t** pdszPdbName
)
{
    HRESULT hr = S_OK;
    CComPtr< IDiaSymbol > pSymbol;
    CDiaString pdbname;

    IfFailGo( GetExeSymbol( &pSymbol ) );

    IfFailGo( pSymbol->get_symbolsFileName( &pdbname ));
    *pdszPdbName = pdbname.Detach();

Error:
    return hr;
}

[KirillOsenkov]

https://msdn.microsoft.com/en-us/library/075yb9bb.aspx

[KirillOsenkov]

I poked around a little bit but couldn't find an easy way to get at the full path to the .pdb (or .dll/.exe in case of embedded .pdb).

Feels like to implement this one would need to thread the filepath through somehow. Not sure what's the best way to do it.

[tmat]

Where is this API used?

Some APIs on ISymUnmanagedBinder take the path. So they should probably pass it to SymReader ctor as an optional parameter, so that SymReader can return the path.

[KirillOsenkov]

One sample usage is in Mdbg:

System.NotImplementedException: The method or operation is not implemented.
   at int Microsoft.DiaSymReader.PortablePdb.SymReader.GetSymbolStoreFileName(int bufferLength, out int count, out char[] name)
   at string Microsoft.Samples.Debugging.CorSymbolStore.SymReader.GetSymbolStoreFileName()
   at string Microsoft.Samples.Debugging.MdbgEngine.ManagedModule.get_SymbolFilename()

When creating a ManagedModule they access and store the .pdb file path.

I was thinking about passing through an optional path from the creators of SymReader. It felt a bit dirty as otherwise SymReader is fully isolated from where the symbols came from (stream, file, etc). Maybe still worth it.

[tmat]

ISymUnmanagedReader is all dirty API :(

You can also try to fix Mdbg to not use this API.

[KirillOsenkov]

Yup, just worked around it. If I know that the API will throw, why call it in the first place. Going to live with a patched Mdbg for a while.