ComSession.h

/*!
 * \brief   The file contains COM session abstruction interface
 * \author  \verbatim
            Created by: Alexander Egorov
            \endverbatim
 * \date    \verbatim
            Creation date: 2010-04-11
            \endverbatim
 * Copyright 2008-2012 Alexander Egorov <egoroff@gmail.com> (http://www.egoroff.spb.ru)
 */

#pragma once

/**
 * \brief Represents a COM session abstruction. Contains different COM infrastructure helpers methods.
 */
class ComSession {
    public:
        /**
         * \brief Creates new ComSession instance.
         */
        ComSession();

        /**
         * \brief Virtual descructor
         */
        virtual ~ComSession();

    protected:
        /**
         * \brief Just calls CoUninitialize();
         */
        virtual void Clear();

        /**
         * \brief Checks HRESULT and throws exception in case of an error (bad HRESULT)
         * @param result HRESULT to check
         * @param pMessage Error message
         */
        void ThrowIfError(HRESULT result, __in LPCWSTR pMessage) const;

        /**
         * \brief Checks HRESULT and throws exception in case of an error (bad HRESULT)
         * @param result HRESULT to check
         * @param pObjectWithError Checked object
         * @param rErrorInterface Checked object's interface
         */
        void ThrowIfError(
            HRESULT        result,
            __in IUnknown* pObjectWithError,
            REFIID         rErrorInterface) const;
    private:
        void DumpErrorInfo(IUnknown *, REFIID) const;

        /**
         * \brief DumpErrorInfo queries SQLOLEDB error interfaces, retrieving available  status or error information.
         */
        void DumpErrorInfo(__in std::wostream *, IUnknown *, REFIID) const;
        DISALLOW_COPY_AND_ASSIGN(ComSession);
};