DBEEPER.CPP

/* 
* DBEEPER.CPP
* Beeper Automation Object Chapter 14
*
* Server module code for the Beeper object.
*
* Copyright (c)1993-1995 Microsoft Corporation, All Rights Reserved
*
* Kraig Brockschmidt, Microsoft
* Internet : kraigb@microsoft.com
* Compuserve: >INTERNET:kraigb@microsoft.com
*/


#define INITGUIDS
#include "dbeeper.h"


//Count number of objects and number of locks.
ULONG g_cObj=0;
ULONG g_cLock=0;
HINSTANCE g_hInst=NULL; //For LoadString


/*
* LibMain(32)
*
* Purpose:
* Entry point conditionally compiled for Win32 and Windows
* 3.1. Provides the proper structure for each environment.
*/

#ifdef WIN32
BOOL WINAPI LibMain32(HINSTANCE hInstance, ULONG ulReason
, LPVOID pvReserved)
{
g_hInst=hInstance;

if (DLL_PROCESS_DETACH==ulReason)
{
return TRUE;
}
else
{
if (DLL_PROCESS_ATTACH!=ulReason)
return TRUE;
}

return TRUE;
}
#else
int PASCAL LibMain(HINSTANCE hInstance, WORD wDataSeg
, WORD cbHeapSize, LPSTR lpCmdLine)
{
if (0!=cbHeapSize)
UnlockData(0);

g_hInst=hInstance;
return (int)hInstance;
}
#endif



/*
* DllGetClassObject
* DllCanUnloadNow
* Standard COM exports for DLL servers.
*/

HRESULT APIENTRY DllGetClassObject(REFCLSID rclsid, REFIID riid
, PPVOID ppv)
{
CBeeperFactory *pBF;
HRESULT hr;

if (CLSID_Beeper!=rclsid)
return ResultFromScode(E_FAIL);

//Check that we can provide the interface
if (IID_IUnknown!=riid && IID_IClassFactory!=riid)
return ResultFromScode(E_NOINTERFACE);

//Return our beeper factory's IClassFactory
pBF=new CBeeperFactory();

if (NULL==pBF)
return ResultFromScode(E_OUTOFMEMORY);

//If the factory hasn't the interface, delete it
hr=pBF->QueryInterface(riid, ppv);

if (FAILED(hr))
delete pBF;
else
g_cObj++;

return hr;
}


STDAPI DllCanUnloadNow(void)
{
SCODE sc;

//Our answer is whether there are any object or locks
sc=(0L==g_cObj && 0L==g_cLock) ? S_OK : S_FALSE;
return ResultFromScode(sc);
}



/*
* ObjectDestroyed
*
* Purpose:
* Function for the object to call when it gets destroyed. Since
* we're in a DLL we only track the number of objects here, letting
* DllCanUnloadNow take care of the rest.
*/

void ObjectDestroyed(void)
{
g_cObj--;
return;
}



/*
* CBeeperFactory::CBeeperFactory
* CBeeperFactory::~CBeeperFactory
*/

CBeeperFactory::CBeeperFactory(void)
{
m_cRef=0L;
return;
}


CBeeperFactory::~CBeeperFactory(void)
{
return;
}






/*
* CBeeperFactory::QueryInterface
* CBeeperFactory::AddRef
* CBeeperFactory::Release
*/

STDMETHODIMP CBeeperFactory::QueryInterface(REFIID riid, PPVOID ppv)
{
*ppv=NULL;

if (IID_IUnknown==riid || IID_IClassFactory==riid)
*ppv=this;

if (NULL!=*ppv)
{
((LPUNKNOWN)*ppv)->AddRef();
return NOERROR;
}

return ResultFromScode(E_NOINTERFACE);
}


STDMETHODIMP_(ULONG) CBeeperFactory::AddRef(void)
{
return ++m_cRef;
}


STDMETHODIMP_(ULONG) CBeeperFactory::Release(void)
{
if (0!=--m_cRef)
return m_cRef;

delete this;
ObjectDestroyed();
return 0;
}



/*
* CBeeperFactory::CreateInstance
* CBeeperFactory::LockServer
*/

STDMETHODIMP CBeeperFactory::CreateInstance(LPUNKNOWN pUnkOuter
, REFIID riid, PPVOID ppvObj)
{
PCBeeper pObj;
HRESULT hr;

*ppvObj=NULL;
hr=ResultFromScode(E_OUTOFMEMORY);

//Verify that a controlling unknown asks for IUnknown
if (NULL!=pUnkOuter && IID_IUnknown!=riid)
return ResultFromScode(CLASS_E_NOAGGREGATION);

//Create the object passing function to notify on destruction.
pObj=new CBeeper(pUnkOuter, ObjectDestroyed);

if (NULL==pObj)
return hr;

if (pObj->Init())
hr=pObj->QueryInterface(riid, ppvObj);

//Kill the object if initial creation or Init failed.
if (FAILED(hr))
delete pObj;
else
g_cObj++;

return hr;
}


STDMETHODIMP CBeeperFactory::LockServer(BOOL fLock)
{
if (fLock)
g_cLock++;
else
g_cLock--;

return NOERROR;
}