windows-server-2003/shell/cpls/desknt5/util.cpp

/*****************************************************************************\
    FILE: util.cpp

    DESCRIPTION:
        Shared stuff that operates on all classes.

    BryanSt 5/30/2000
    Copyright (C) Microsoft Corp 2000-2000. All rights reserved.
\*****************************************************************************/

#include "precomp.h"
#pragma hdrstop

#include "util.h"

BOOL IUnknown_CompareCLSID(IN IUnknown * punk, IN CLSID clsid)
{
    BOOL fIsEqual = FALSE;

    if (punk)
    {
        CLSID clsidPageID;
        HRESULT hr = IUnknown_GetClassID(punk, &clsidPageID);

        if (SUCCEEDED(hr) && IsEqualCLSID(clsidPageID, clsid))
        {
            fIsEqual = TRUE;
        }
    }

    return fIsEqual;
}


HRESULT IEnumUnknown_FindCLSID(IN IUnknown * punk, IN CLSID clsid, OUT IUnknown ** ppunkFound)
{
    HRESULT hr = E_INVALIDARG;

    if (punk && ppunkFound)
    {
        IEnumUnknown * pEnum;

        *ppunkFound = NULL;
        hr = punk->QueryInterface(IID_PPV_ARG(IEnumUnknown, &pEnum));
        if (SUCCEEDED(hr))
        {
            IUnknown * punkToTry;
            ULONG ulFetched;

            while (SUCCEEDED(pEnum->Next(1, &punkToTry, &ulFetched)) &&
                (1 == ulFetched))
            {
                if (IUnknown_CompareCLSID(punkToTry, clsid))
                {
                    *ppunkFound = punkToTry;
                    break;
                }

                punkToTry->Release();
            }

            pEnum->Release();
        }
    }

    return hr;
}

HRESULT GetPageByCLSID(IUnknown * punkSite, const GUID * pClsid, IPropertyBag ** ppPropertyBag)
{
    HRESULT hr = E_FAIL;

    *ppPropertyBag = NULL;
    if (punkSite)
    {
        IThemeUIPages * pThemeUI;

        hr = punkSite->QueryInterface(IID_PPV_ARG(IThemeUIPages, &pThemeUI));
        if (SUCCEEDED(hr))
        {
            IEnumUnknown * pEnumUnknown;

            hr = pThemeUI->GetBasePagesEnum(&pEnumUnknown);
            if (SUCCEEDED(hr))
            {
                IUnknown * punk;

                // This may not exit due to policy
                hr = IEnumUnknown_FindCLSID(pEnumUnknown, *pClsid, &punk);
                if (SUCCEEDED(hr))
                {
                    hr = punk->QueryInterface(IID_PPV_ARG(IPropertyBag, ppPropertyBag));
                    punk->Release();
                }

                pEnumUnknown->Release();
            }

            pThemeUI->Release();
        }
    }

    return hr;
}