windows-server-2003/admin/services/drizzle/newjob/proxy.h

inline DWORD
ProxyUsageFromJobProxyUsage(
    BG_JOB_PROXY_USAGE JobUsage
    )
{
    switch( JobUsage )
        {
        case BG_JOB_PROXY_USAGE_PRECONFIG: return WINHTTP_ACCESS_TYPE_DEFAULT_PROXY;
        case BG_JOB_PROXY_USAGE_NO_PROXY:  return WINHTTP_ACCESS_TYPE_NO_PROXY;
        case BG_JOB_PROXY_USAGE_OVERRIDE:  return WINHTTP_ACCESS_TYPE_NAMED_PROXY;
        default:                           ASSERT( 0 ); return WINHTTP_ACCESS_TYPE_NO_PROXY;
        }
}


struct PROXY_SETTINGS
{
   BG_JOB_PROXY_USAGE   ProxyUsage;
   LPTSTR               ProxyList;
   LPTSTR               ProxyBypassList;

   PROXY_SETTINGS()
   {
       ProxyUsage = BG_JOB_PROXY_USAGE_PRECONFIG;

       ProxyList       =  NULL;
       ProxyBypassList =  NULL;
   }

   ~PROXY_SETTINGS()
   {
       delete ProxyList;
       delete ProxyBypassList;
   }
};

class PROXY_SETTINGS_CONTAINER
{
    DWORD           m_ProxyUsage;
    StringHandle    m_BypassList;
    StringHandle    m_MasterProxyList;
    DWORD           m_AccessType;

    StringHandle    m_ProxyList;
    LPWSTR          m_CurrentProxy;
    LPWSTR          m_TokenCursor;

public:

    PROXY_SETTINGS_CONTAINER(
        LPCWSTR Url,
        const PROXY_SETTINGS * ProxySettings
        );

    bool UseNextProxy()
    {
        m_CurrentProxy = m_ProxyList.GetToken( m_TokenCursor, _T("; "), &m_TokenCursor );
        if (m_CurrentProxy == NULL)
            {
            return false;
            }

        return true;
    }

    void ResetCurrentProxy()
    {
        m_ProxyList = m_MasterProxyList.Copy();

        m_CurrentProxy = m_ProxyList.GetToken( NULL, _T(";"), &m_TokenCursor );
    }

    DWORD GetProxyUsage()
    {
        return m_ProxyUsage;
    }

    LPCWSTR GetCurrentProxy()
    {
        return m_CurrentProxy;
    }

    LPCWSTR GetProxyList()
    {
        return m_MasterProxyList;
    }

    LPCWSTR GetBypassList()
    {
        if (static_cast<LPCWSTR>(m_BypassList)[0] == 0)
            {
            return NULL;
            }

        return m_BypassList;
    }
};

class CACHED_AUTOPROXY
{
public:

    // a cache entry lasts for 5 minutes.
    //
    const static CACHED_PROXY_LIFETIME_IN_MSEC = (5 * 60 * 1000);

    //----------------------------------------------------------

    inline CACHED_AUTOPROXY()
    {
        m_fValid = false;
        m_TimeStamp = 0;
        m_hInternet = 0;

        ZeroMemory(&m_ProxyInfo, sizeof(m_ProxyInfo));

        m_hInternet = WinHttpOpen( C_BITS_USER_AGENT,
                                    WINHTTP_ACCESS_TYPE_DEFAULT_PROXY,
                                    NULL,  // proxy list
                                    NULL,  // proxy bypass list
                                    0 );
        if (!m_hInternet)
            {
            ThrowLastError();
            }
    }

    inline ~CACHED_AUTOPROXY()
    {
        Clear();

        if (m_hInternet)
            {
            InternetCloseHandle( m_hInternet );
            }
    }

    void Clear();

    HRESULT
    Generate(
        const TCHAR Host[]
        );

    HRESULT
    SetRequestProxy(
        HINTERNET hRequest,
        const PROXY_SETTINGS * ProxySettings
        );

    void Invalidate()
    /*
        When the set of network interfaces changes, cached results may no longer be valid.
        A separate thread will call this function to mark the results invalid.
        This function is safe to call while the downloader thread is calling Generate().
        If that becomes untrue, then explicit synchronization will be needed.
    */
    {
        //
        // Invalidate m_HostName.  We don't touch it, because Generate() may be using it.
        //
        m_TimeStamp = GetTickCount() - CACHED_PROXY_LIFETIME_IN_MSEC - 1;
    }

    LPCWSTR GetProxyList()
    {
        return m_ProxyInfo.lpszProxy;
    }

    LPCWSTR GetBypassList()
    {
        return m_ProxyInfo.lpszProxyBypass;
    }

    DWORD GetAccessType()
    {
        return m_ProxyInfo.dwAccessType;
    }

protected:

    //
    // m_ProxyInfo contains valid data.
    //
    bool m_fValid;

    //
    // The host used to calculate the proxy value.
    //
    StringHandleT   m_HostName;

    //
    // The results of the proxy calculation.
    //
    WINHTTP_PROXY_INFO m_ProxyInfo;

    //
    // Time of last update.
    //
    long m_TimeStamp;

    HINTERNET m_hInternet;
};