DBSESS.CPP

//-------------------------------------------------------------------- 
// Microsoft OLE DB Sample Provider 
// (C) Copyright 1994 - 1996 Microsoft Corporation.  All Rights Reserved. 
// 
// @doc 
// 
// @module DBSESS.CPP | CDBSession object implementation 
// 
// 
 
// Includes ------------------------------------------------------------------ 
 
#include "headers.h" 
 
 
// Code ---------------------------------------------------------------------- 
 
// CDBSession::CDBSession -------------------------------------------------- 
// 
// @mfunc Constructor for this class 
// 
// @rdesc NONE 
// 
CDBSession::CDBSession 
    ( 
    LPUNKNOWN pUnkOuter         //@parm IN | Outer Unkown Pointer 
    ) 
{ 
    //  Initialize simple member vars 
    m_cRef              = 0L; 
    m_pUnkOuter         = pUnkOuter; 
    *m_szPath           = '\0'; 
    m_fRowsetCreated    = FALSE; 
 
    // Initially, NULL all contained interfaces 
    m_pIGetDataSource= NULL; 
    m_pIOpenRowset= NULL; 
 
// Pointer to parent object 
m_pCDataSource= NULL; 
 
    // Increment global object count. 
    OBJECT_CONSTRUCTED(); 
 
    return; 
} 
 
 
// CDBSession::~CDBSession ------------------------------------------------- 
// 
// @mfunc Destructor for this class 
// 
// @rdesc NONE 
// 
CDBSession:: ~CDBSession 
    ( 
    void 
    ) 
{ 
    // Free contained interfaces 
    delete m_pIGetDataSource; 
    delete m_pIOpenRowset; 
 
m_pCDataSource->Release(); 
m_pCDataSource->RemoveSession(); 
 
    // Decrement global object count. 
    OBJECT_DESTRUCTED(); 
 
    return; 
} 
 
 
// CDBSession::FInit -------------------------------------------------------- 
// 
// @mfunc Initialize the command Object 
// 
// @rdesc Did the Initialization Succeed 
//      @flag  TRUE | Initialization succeeded 
//      @flag  FALSE | Initialization failed 
// 
BOOL CDBSession::FInit 
    ( 
    char*szPath, 
CDataSource*pCDataSource 
    ) 
{ 
    LPUNKNOWN   pIUnknown = (LPUNKNOWN) this; 
 
    if (m_pUnkOuter) 
        pIUnknown = m_pUnkOuter; 
 
    // just make a copy for ourselves. 
    if (!lstrcpyn( m_szPath, szPath, MAX_PATH )) 
        return FALSE; 
 
// Establish parent object pointer 
assert( pCDataSource ); 
m_pCDataSource= pCDataSource; 
 
m_pCDataSource->AddRef(); 
 
    // Allocate contained interface objects 
    m_pIGetDataSource= new CImpIGetDataSource( this, pIUnknown ); 
    m_pIOpenRowset= new CImpIOpenRowset( this, pIUnknown ); 
    m_pISessionProperties= new CImpISessionProperties( this, pIUnknown ); 
 
    return (BOOL) (m_pIGetDataSource && m_pIOpenRowset); 
} 
 
 
 
// CDBSession::QueryInterface ----------------------------------------------- 
// 
// @mfunc Returns a pointer to a specified interface. Callers use 
// QueryInterface to determine which interfaces the called object 
// supports. 
// 
// @rdesc HRESULT indicating the status of the method 
//      @flag S_OK          | Interface is supported and ppvObject is set. 
//      @flag E_NOINTERFACE | Interface is not supported by the object 
//      @flag E_INVALIDARG  | One or more arguments are invalid. 
// 
STDMETHODIMP CDBSession::QueryInterface 
    ( 
    REFIID riid,        //@parm IN | Interface ID of the interface being queried for. 
    LPVOID * ppv        //@parm OUT | Pointer to interface that was instantiated 
    ) 
{ 
    // Is the pointer bad? 
    if (ppv == NULL) 
        return ResultFromScode( E_INVALIDARG ); 
 
    //  Place NULL in *ppv in case of failure 
    *ppv = NULL; 
 
    //  This is the non-delegating IUnknown implementation 
    if (riid == IID_IUnknown) 
        *ppv = (LPVOID) this; 
else if (!m_pCDataSource->m_fDSOInitialized) 
return ResultFromScode(E_UNEXPECTED); 
    else if (riid == IID_IGetDataSource) 
        *ppv = (LPVOID) m_pIGetDataSource; 
    else if (riid == IID_IOpenRowset) 
        *ppv = (LPVOID) m_pIOpenRowset; 
    else if (riid == IID_ISessionProperties) 
        *ppv = (LPVOID) m_pISessionProperties; 
 
    //  If we're going to return an interface, AddRef it first 
    if (*ppv) 
        { 
        ((LPUNKNOWN) *ppv)->AddRef(); 
        return ResultFromScode( S_OK ); 
        } 
    else 
        return ResultFromScode( E_NOINTERFACE ); 
} 
 
 
// CDBSession::AddRef ------------------------------------------------------- 
// 
// @mfunc Increments a persistence count for the object 
// 
// @rdesc Current reference count 
// 
STDMETHODIMP_( ULONG ) CDBSession::AddRef 
     ( 
     void 
     ) 
{ 
    return ++m_cRef; 
} 
 
 
// CDBSession::Release ------------------------------------------------------ 
// 
// @mfunc Decrements a persistence count for the object and if 
// persistence count is 0, the object destroys itself. 
// 
// @rdesc Current reference count 
// 
STDMETHODIMP_( ULONG ) CDBSession::Release 
     ( 
     void 
     ) 
{ 
    if (!--m_cRef) 
        { 
        delete this; 
        return 0; 
        } 
 
    return m_cRef; 
} 
 
//----------------------------------------------------------------------------- 
// CImpIGetDataSource::GetDataSource  
// 
// @mfunc Retrieve an interface pointer on the session object 
// 
// @rdesc  
//@flag S_OK | Session Object Interface returned 
//@flag E_INVALIDARG | ppDataSource was NULL 
//@flag E_NOINTERFACE | IID not supported 
// 
STDMETHODIMP CImpIGetDataSource::GetDataSource 
( 
REFIIDriid,// @parm IN  | IID desired 
IUnknown**ppDataSource// @parm OUT | ptr to interface 
) 
{ 
// Check Function Arguments 
if( ppDataSource == NULL ) 
return ResultFromScode(E_INVALIDARG); 
 
assert( m_pObj->m_pCDataSource ); 
return ((m_pObj->m_pCDataSource)->QueryInterface(riid, (LPVOID*)ppDataSource)); 
} 
 
// ISessionProperties::GetProperties ---------------------------------------------------- 
// 
// @mfunc Returns current settings of all properties in the DBPROPFLAGS_SESSION property  
//group 
// @rdesc HRESULT 
//      @flag S_OK          | The method succeeded 
//      @flag E_INVALIDARG  | pcProperties or prgPropertyInfo was NULL 
//      @flag E_OUTOFMEMORY | Out of memory 
// 
STDMETHODIMP CImpISessionProperties::GetProperties 
    ( 
    ULONGcPropertySets,//@parm IN | count of restiction guids 
const DBPROPIDSETrgPropertySets[],//@parm IN | restriction guids 
ULONG*              pcProperties,//@parm OUT | count of properties returned 
DBPROPSET**prgProperties//@parm OUT | property information returned 
    ) 
{ 
    assert( m_pObj ); 
    assert( m_pObj->m_pUtilProp ); 
 
    // just pass this call on to the utility object that manages our properties 
    return m_pObj->m_pUtilProp->GetProperties(  
cPropertySets,  
rgPropertySets, 
pcProperties,  
prgProperties ); 
} 
 
 
// CImpISessionProperties::SetProperties  -------------------------------------------- 
// 
// @mfunc Set properties in the DBPROPFLAGS_SESSION property group 
// 
// @rdesc HRESULT 
//      @flag E_INVALIDARG  | cProperties was not equal to 0 and rgProperties was NULL 
//      @flag E_NOTIMPL| this method is not implemented 
// 
STDMETHODIMP    CImpISessionProperties::SetProperties 
    ( 
    ULONGcProperties, 
DBPROPSETrgProperties[] 
) 
{ 
    assert( m_pObj ); 
    assert( m_pObj->m_pUtilProp ); 
 
    // just pass this call on to the utility object that manages our properties 
    return m_pObj->m_pUtilProp->SetProperties(  
cProperties,  
rgProperties); 
}