DISPCALC.CPP

/***  
*dispcalc.cpp
*
* This is a part of the Microsoft Source Code Samples.
*
* Copyright 1992 - 1998 Microsoft Corporation. All rights reserved.
*
* This source code is only intended as a supplement to Microsoft Development
* Tools and/or WinHelp documentation. See these sources for detailed
* information regarding the Microsoft samples programs.
*
*Purpose:
* This module implements the basic user interface and arithmetic
* functionality of the IDispatch calculator.
*
* The implementation of IDispatch it via aggregation with an
* instance of the "standard" IDispatch implementation, which is
* initialized with a DispTypeInfo constructed from an INTERFACEDATA
* description.
*
*Implementation Notes:
*
*****************************************************************************/

#include "dispcalc.h"

CCalc FAR* g_pcalc = NULL;

unsigned long g_dwCCalcCF = 0;
unsigned long g_dwRegisterCCalc = 0;

#ifdef _MAC
extern Boolean g_fQuit;
#endif //_MAC


CCalc::CCalc() : m_arith(this)
{
m_refs = 0;
#ifdef _MAC
m_pdlg = nil;
#else
m_hwnd = NULL;
#endif
m_punkStdDisp = NULL;
}

/***
*CCalc *CCalc::Create(void)
*Purpose:
* Create an instance of the IDispatch calculator, build a
* TypeInfo that describes the exposed functionality and
* aggregate with an instance of CStdDispatch that has been
* initialized with this TypeInfo.
*
*Entry:
* None
*
*Exit:
* return value = CCalc*, NULL if the creation failed.
*
***********************************************************************/
CCalc FAR*
CCalc::Create()
{
HRESULT hresult;
CCalc FAR* pcalc;
CArith FAR* parith;
ITypeInfo FAR* ptinfo;
IUnknown FAR* punkStdDisp;
extern INTERFACEDATA NEARDATA g_idataCCalc;

if((pcalc = new FAR CCalc()) == NULL)
return NULL;
pcalc->AddRef();

parith = &(pcalc->m_arith);

// Build a TypeInfo for the functionality on this object that
// is being exposing for external programmability.
//
hresult = CreateDispTypeInfo(
&g_idataCCalc, LOCALE_SYSTEM_DEFAULT, &ptinfo);
if(hresult != NOERROR)
goto LError0;

// Create and aggregate with an instance of the default
// implementation of IDispatch that is initialized with our
// TypeInfo.
//
hresult = CreateStdDispatch(
pcalc, // controlling unknown
parith, // instance to dispatch on
ptinfo, // typeinfo describing the instance
&punkStdDisp);

ptinfo->Release();

if(hresult != NOERROR)
goto LError0;

pcalc->m_punkStdDisp = punkStdDisp;

return pcalc;

LError0:;
pcalc->Release();

return NULL;
}

//---------------------------------------------------------------------
// IUnknown methods
//---------------------------------------------------------------------

STDMETHODIMP
CCalc::QueryInterface(REFIID riid, void FAR* FAR* ppv)
{
if(IsEqualIID(riid, IID_IUnknown)){
*ppv = this;
}else
if(IsEqualIID(riid, IID_IDispatch)){
return m_punkStdDisp->QueryInterface(riid, ppv);
}else {
*ppv = NULL;
return E_NOINTERFACE;
}

AddRef();
return NOERROR;
}

STDMETHODIMP_(unsigned long)
CCalc::AddRef()
{
return ++m_refs;
}

STDMETHODIMP_(unsigned long)
CCalc::Release()
{
if(--m_refs == 0){
if(m_punkStdDisp != NULL)
m_punkStdDisp->Release();
#ifndef _MAC
PostQuitMessage(0);
#endif
delete this;
return 0;
}
return m_refs;
}


//---------------------------------------------------------------------
// Arithmetic features
//---------------------------------------------------------------------

STDMETHODIMP_(void)
CArith::Clear()
{
m_opnd = 0;
m_accum = 0;
m_op = OP_NONE;
m_state = STATE_LOPND;
}

STDMETHODIMP_(void)
CArith::put_Accum(long l)
{
m_accum = l;
}


STDMETHODIMP_(long)
CArith::get_Accum()
{
return m_accum;
}

STDMETHODIMP_(void)
CArith::put_Opnd(long l)
{
m_opnd = l;
}

STDMETHODIMP_(long)
CArith::get_Opnd()
{
return m_opnd;
}

STDMETHODIMP_(void)
CArith::put_Op(short op)
{
m_op = op;
}

STDMETHODIMP_(short)
CArith::get_Op()
{
return m_op;
}

STDMETHODIMP_(short)
CArith::Eval()
{
if(m_op == OP_NONE)
return 0;

switch(m_op){
case OP_PLUS:
m_accum += m_opnd;
break;
case OP_MINUS:
m_accum -= m_opnd;
break;
case OP_MULT:
m_accum *= m_opnd;
break;
case OP_DIV:
m_accum = (m_opnd == 0) ? 0 : (m_accum / m_opnd);
break;
default:
// ASSERT(UNREACHED);
return 0;

}

m_state = STATE_EVAL;

return 1;
}


//---------------------------------------------------------------------
// User Interface features
//---------------------------------------------------------------------

/***
*void CArith::Display()
*Purpose:
* Display the contents of the register currently being edited.
*
*Entry:
* None
*
*Exit:
* None
*
***********************************************************************/
STDMETHODIMP_(void)
CArith::Display()
{
VARIANT var;

VariantInit(&var);

V_VT(&var) = VT_I4;
V_I4(&var) = (m_state == STATE_ROPND) ? m_opnd : m_accum;
VariantChangeType(&var, &var, 0, VT_BSTR);

#ifdef _MAC
{
Rect rcItem;
Handle hItem;
char str[255];
short sItemKind;

strcpy(str, V_BSTR(&var));
GetDItem(m_pcalc->m_pdlg, IDC_DISPLAY, &sItemKind, &hItem, &rcItem);
SetIText(hItem, c2pstr(str));
}
#else
SetDlgItemText(m_pcalc->m_hwnd, IDC_DISPLAY, STRING(V_BSTR(&var)));
#endif

VariantClear(&var);
}

STDMETHODIMP_(short)
CArith::Button(BSTR bstrButton)
{
int i, button;

static struct {
OLECHAR ch;
int idc;
} NEARDATA rgIdcOfCh[] = {
{ OLESTR('+'), IDC_PLUS }
, { OLESTR('-'), IDC_MINUS }
, { OLESTR('*'), IDC_MULT }
, { OLESTR('/'), IDC_DIV }
, { OLESTR('C'), IDC_CLEAR }
, { OLESTR('c'), IDC_CLEAR }
, { OLESTR('='), IDC_EQUALS }
, { OLESTR('0'), IDC_ZERO }
, { OLESTR('1'), IDC_ONE }
, { OLESTR('2'), IDC_TWO }
, { OLESTR('3'), IDC_THREE }
, { OLESTR('4'), IDC_FOUR }
, { OLESTR('5'), IDC_FIVE }
, { OLESTR('6'), IDC_SIX }
, { OLESTR('7'), IDC_SEVEN }
, { OLESTR('8'), IDC_EIGHT }
, { OLESTR('9'), IDC_NINE }
, { (OLECHAR)-1 , -1 }
};

// if the string is more that 1 character long, then we know its wrong.
if(SysStringLen(bstrButton) > 1)
return 0;

// translate button string into control ID
for(i = 0;; ++i){
if(rgIdcOfCh[i].ch == -1)
return 0;
if(rgIdcOfCh[i].ch == bstrButton[0]){
button = rgIdcOfCh[i].idc;
break;
}
}

return ButtonPush(button);
}

// the following method is internal, and not exposed for programmability
int
CArith::ButtonPush(int button)
{
if(button >= IDC_ZERO && button <= IDC_NINE){

long lVal = button - IDC_ZERO;

switch(m_state){
case STATE_EVAL:
m_accum = lVal;
m_state = STATE_LOPND;
break;
case STATE_OP:
m_opnd = lVal;
m_state = STATE_ROPND;
break;
case STATE_LOPND:
m_accum = (m_accum * 10) + lVal;
break;
case STATE_ROPND:
m_opnd = (m_opnd * 10) + lVal;
break;
}

}else if(button >= IDC_PLUS && button <= IDC_DIV){

if(m_state == STATE_ROPND)
Eval();

m_opnd = m_accum;
m_state = STATE_OP;
m_op = button - IDC_PLUS + OP_PLUS;

}else if(button == IDC_EQUALS){

if(m_state > STATE_LOPND)
Eval();

}else if (button == IDC_CLEAR){

Clear();

}else{

return 0; // unknown button

}

// Flash the button

#ifdef _MAC
{
Rect rcItem;
long lDummy;
Handle hItem;
short sItemKind;

GetDItem(m_pcalc->m_pdlg, button, &sItemKind, &hItem, &rcItem);
HiliteControl((ControlHandle)hItem, 1);
Delay(6, &lDummy);
HiliteControl((ControlHandle)hItem, 0);
}
#else
SendMessage(m_pcalc->m_hwnd, BM_SETSTATE, 1, 0L);
SendMessage(m_pcalc->m_hwnd, BM_SETSTATE, 0, 0L);
#endif

// Update the calculator display

Display();

return 1;
}

/***
*void CArith::Quit()
*Purpose:
*
*Entry:
* None
*
*Exit:
* None
*
***********************************************************************/
STDMETHODIMP_(void)
CArith::Quit()
{
#ifndef _MAC
PostQuitMessage(0);
#else
g_fQuit = 1;
#endif
}


//---------------------------------------------------------------------
// The CCalc Class Factory
//---------------------------------------------------------------------

IClassFactory FAR*
CCalcCF::Create()
{
return new FAR CCalcCF();
}

STDMETHODIMP
CCalcCF::QueryInterface(REFIID riid, void FAR* FAR* ppv)
{
if(IsEqualIID(riid, IID_IUnknown) ||
IsEqualIID(riid, IID_IClassFactory)){
AddRef();
*ppv = this;
return NOERROR;
}

*ppv = NULL;
return E_NOINTERFACE;
}

STDMETHODIMP_(unsigned long)
CCalcCF::AddRef()
{
return ++m_refs;
}

STDMETHODIMP_(unsigned long)
CCalcCF::Release()
{
if(--m_refs == 0){
delete this;
return 0;
}
return m_refs;
}

STDMETHODIMP
CCalcCF::CreateInstance(
IUnknown FAR* punkOuter,
REFIID riid,
void FAR* FAR* ppv)
{
if(punkOuter != NULL)
return CLASS_E_NOAGGREGATION;
return g_pcalc->QueryInterface(riid, ppv);
}

STDMETHODIMP
#ifdef _MAC
CCalcCF::LockServer(unsigned long fLock)
#else
CCalcCF::LockServer(BOOL fLock)
#endif
{
UNUSED(fLock);
return NOERROR;
}


//---------------------------------------------------------------------
// Ole Init/Uninit
//---------------------------------------------------------------------

HRESULT
UninitOle()
{
if(g_dwRegisterCCalc != 0)
RevokeActiveObject(g_dwRegisterCCalc, NULL);

if(g_dwCCalcCF != 0)
CoRevokeClassObject(g_dwCCalcCF);

if(g_pcalc != NULL)
g_pcalc->Release();

OleUninitialize();

return NOERROR;
}

#ifdef _MAC
struct regentry{
char *szKey;
char *szValue;
} g_rgregentry[] = {

{ "CLSID\\{00020467-0000-0000-C000-000000000046}",
"OLE Automation DispCalc 1.0 Application" }

, { "CLSID\\{00020467-0000-0000-C000-000000000046}\\LocalServer",
"DCLC" }

, { "CLSID\\{00020467-0000-0000-C000-000000000046}\\ProgID",
"Dispcalc.Application" }

, { "CLSID\\{00020467-0000-0000-C000-000000000046}\\InprocHandler",
"OLE2:Def$DefFSet" }

, { "DCLC", "{00020467-0000-0000-C000-000000000046}" }

, { "Dispcalc.Application\\CLSID",
"{00020467-0000-0000-C000-000000000046}" }

};

HRESULT
EnsureRegistration()
{
HKEY hkey;

if(RegOpenKey(HKEY_CLASSES_ROOT, "DCLC", &hkey) == NOERROR){
RegCloseKey(hkey);
return NOERROR;
}

for(int i = 0; i < DIM(g_rgregentry); ++i){
if(RegSetValue(HKEY_CLASSES_ROOT, g_rgregentry[i].szKey, REG_SZ, g_rgregentry[i].szValue, 0) != ERROR_SUCCESS)
return E_FAIL;
}

return NOERROR;
}
#endif

/***
*HRESULT InitOle(void)
*Purpose:
* Initialize Ole, and register our class factories.
*
*Entry:
* None
*
*Exit:
* None
*
***********************************************************************/
HRESULT
InitOle()
{
HRESULT hresult;
IClassFactory FAR* pcf;

if(FAILED(hresult = OleInitialize(NULL)))
goto LError0;

#ifdef _MAC
if(FAILED(hresult = EnsureRegistration()))
goto LError0;
#endif

// create the single global instance of CCalc
if((g_pcalc = CCalc::Create()) == NULL){
hresult = E_OUTOFMEMORY;
goto LError0;
}

if((pcf = CCalcCF::Create()) == NULL)
goto LError1;

hresult = CoRegisterClassObject(
CLSID_CCalc,
pcf,
CLSCTX_LOCAL_SERVER,
REGCLS_MULTIPLEUSE,
&g_dwCCalcCF);
if(FAILED(hresult))
goto LError2;

hresult = RegisterActiveObject(
g_pcalc, CLSID_CCalc, NULL, &g_dwRegisterCCalc);
if(FAILED(hresult))
goto LError2;

pcf->Release();

return NOERROR;

LError2:;
pcf->Release();

LError1:;
UninitOle();

LError0:;
return hresult;
}