IEXTCONN.CPP

/* 
 * IEXTCONN.CPP 
 * Polyline Component Chapter 23 
 * 
 * Implementation of IExternalConnection as required for an 
 * in-process object that supports linking to embedding. 
 * Specifically, this will call IOleObject::Close when there 
 * are no more strong locks on the object. 
 * 
 * Copyright (c)1993-1995 Microsoft Corporation, All Rights Reserved 
 * 
 * Kraig Brockschmidt, Microsoft 
 * Internet  :  kraigb@microsoft.com 
 * Compuserve:  >INTERNET:kraigb@microsoft.com 
 */ 
 
 
#include "polyline.h" 
 
 
/* 
 * CImpIExternalConnection::CImpIExternalConnection 
 * CImpIExternalConnection::~CImpIExternalConnection 
 * 
 * Parameters (Constructor): 
 *  pObj            PCPolyline of the object we're in. 
 *  pUnkOuter       LPUNKNOWN to which we delegate. 
 */ 
 
CImpIExternalConnection::CImpIExternalConnection(PCPolyline pObj 
    , LPUNKNOWN pUnkOuter) 
    { 
    m_cRef=0; 
    m_pObj=pObj; 
    m_pUnkOuter=pUnkOuter; 
    m_cLockStrong=0L; 
    return; 
    } 
 
CImpIExternalConnection::~CImpIExternalConnection(void) 
    { 
    return; 
    } 
 
 
 
/* 
 * CImpIExternalConnection::QueryInterface 
 * CImpIExternalConnection::AddRef 
 * CImpIExternalConnection::Release 
 * 
 * Purpose: 
 *  Delegating IUnknown members for CImpIExternalConnection. 
 */ 
 
STDMETHODIMP CImpIExternalConnection::QueryInterface(REFIID riid 
    , LPVOID *ppv) 
    { 
    return m_pUnkOuter->QueryInterface(riid, ppv); 
    } 
 
 
STDMETHODIMP_(ULONG) CImpIExternalConnection::AddRef(void) 
    { 
    ++m_cRef; 
    return m_pUnkOuter->AddRef(); 
    } 
 
STDMETHODIMP_(ULONG) CImpIExternalConnection::Release(void) 
    { 
    --m_cRef; 
    return m_pUnkOuter->Release(); 
    } 
 
 
 
 
/* 
 * CImpIExternalConnection::AddConnection 
 * 
 * Purpose: 
 *  Informs the object that a strong connection has been made to it. 
 * 
 * Parameters: 
 *  dwConn          DWORD identifying the type of connection, taken 
 *                  from the EXTCONN enumeration. 
 *  dwReserved      DWORD reserved.  This is used inside OLE and 
 *                  should not be validated. 
 * 
 * Return Value: 
 *  DWORD           The number of connection counts on the 
 *                  object, used for debugging purposes only. 
 */ 
 
STDMETHODIMP_(DWORD) CImpIExternalConnection::AddConnection 
    (DWORD dwConn, DWORD dwReserved) 
    { 
    if (EXTCONN_STRONG & dwConn) 
        return ++m_cLockStrong; 
 
    return 0; 
    } 
 
 
 
 
 
 
/* 
 * CImpIExternalConnection::ReleaseConnection 
 * 
 * Purpose: 
 *  Informs an object that a connection has been taken away from 
 *  it in which case the object may need to shut down. 
 * 
 * Parameters: 
 *  dwConn              DWORD identifying the type of connection, 
 *                      taken from the EXTCONN enumeration. 
 *  dwReserved          DWORD reserved.  This is used inside OLE and 
 *                      should not be validated. 
 *  dwRerved            DWORD reserved 
 *  fLastReleaseCloses  BOOL indicating if the last call to this 
 *                      function should close the object. 
 * 
 * Return Value: 
 *  DWORD           The number of remaining connection counts on 
 *                  the object, used for debugging purposes only. 
 */ 
 
STDMETHODIMP_(DWORD) CImpIExternalConnection::ReleaseConnection 
    (DWORD dwConn, DWORD dwReserved, BOOL fLastReleaseCloses) 
    { 
    if (EXTCONN_STRONG==dwConn) 
        { 
        if (0==--m_cLockStrong && fLastReleaseCloses) 
            m_pObj->m_pImpIOleObject->Close(OLECLOSE_SAVEIFDIRTY); 
 
        return m_cLockStrong; 
        } 
 
    return 0L; 
    }