CACCOUNT.CPP

// Filename: CAccount.cpp 
// 
// Description: Implementation of CAccount 
// 
// This file is provided as part of the Microsoft Transaction Server 
// Software Development Kit 
// 
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT  
// WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED,  
// INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES  
// OF MERCHANTABILITY AND/OR FITNESS FOR A  PARTICULAR  
// PURPOSE. 
// 
// Copyright (C) 1997 Microsoft Corporation, All rights reserved 
#include "stdafx.h" 
#include "Account.h" 
#include "CAccount.h" 
#include <stdio.h> 
 
#include <mtx.h> 
 
#include <adoid.h> 
#include <adoint.h> 
 
///////////////////////////////////////////////////////////////////////////// 
// 
 
STDMETHODIMP CAccount::InterfaceSupportsErrorInfo(REFIID riid) 
{ 
static const IID* arr[] =  
{ 
&IID_IAccount, 
}; 
 
for (int i=0;i<sizeof(arr)/sizeof(arr[0]);i++) 
{ 
if (InlineIsEqualGUID(*arr[i],riid)) 
return S_OK; 
} 
return S_FALSE; 
} 
 
//Post: modifies the specified account by the specified amount 
// 
//pbstrResult: a BSTR giving information.  NOTE: this is set to NULL when an error occurs 
// 
//returns:  S_OK or E_FAIL 
 
STDMETHODIMP CAccount::Post (IN long lAccount, IN long lAmount, OUT BSTR* pbstrResult) { 
 
HRESULT hr = S_OK; 
 
IObjectContext* pObjectContext = NULL; 
 
ADOConnection* adoCoConnection = NULL; 
ADORecordset* adoRsBalance = NULL; 
ADOFields* pFields = NULL; 
ADOField* pField = NULL; 
 
*pbstrResult = NULL; 
 
long lErrFlag = 0; 
TCHAR* pErrMsg = NULL; 
 
try { 
 
// Get our object context 
THROW_ERR (GetObjectContext(&pObjectContext), "GetObjectContext" ); 
 
// Check security for large transfers 
if (lAmount > 500 || lAmount < -500) { 
BOOL bInRole; 
BSTR bstrRole; 
 
bstrRole = ::SysAllocString(L"Managers"); 
hr = pObjectContext->IsCallerInRole (bstrRole, &bInRole); 
::SysFreeString(bstrRole); 
 
if (!SUCCEEDED ( hr )) { 
THROW_STR ( _T("IsCallerInRole() call failed!  Please add the 'Managers' Roll to the package.")); 
} 
 
if (!bInRole) { 
THROW_STR ( _T("Need 'Managers' role for amounts over $500") ); 
} 
} 
 
// Create ADOConnection object and initialize the connection 
THROW_ERR ( CoCreateInstance (CLSID_CADOConnection, NULL, CLSCTX_INPROC_SERVER, IID_IADOConnection, 
(LPVOID *) &adoCoConnection), "CoCreateInstance(CADOConnection)" ); 
 
BSTR bstrDSN = ::SysAllocString (L"FILEDSN=MTSSamples"); 
hr = adoCoConnection->Open (bstrDSN, NULL, NULL, adCmdUnspecified); 
::SysFreeString (bstrDSN); 
RETHROW_ERR(hr); 
 
// Update the account balance and 
// then check to see if account would be overdrawn 
TCHAR szBuffer [512]; 
wsprintf (szBuffer, _T("UPDATE Account SET Balance = Balance + %li WHERE AccountNo = %li"), 
lAmount, lAccount); 
BSTR bstrSQL = TCHAR2BSTR (szBuffer); 
CComVariant vRecordCount; 
vRecordCount.Clear(); 
hr = adoCoConnection->Execute(bstrSQL, &vRecordCount, -1, NULL); 
::SysFreeString (bstrSQL); 
RETHROW_ERR(hr); 
 
// If no records got updated, the account doesn't exist 
if (vRecordCount.lVal == 0) { 
TCHAR szBuffer1 [512]; 
wsprintf (szBuffer1, _T("Error. Account %ld not on file."), lAccount); 
THROW_STR ( szBuffer1 ); 
} 
 
wsprintf (szBuffer, _T("SELECT Balance FROM Account WHERE AccountNo = %ld"), lAccount); 
bstrSQL = TCHAR2BSTR (szBuffer); 
hr = adoCoConnection->Execute (bstrSQL, &vRecordCount, -1, &adoRsBalance); 
::SysFreeString (bstrSQL); 
RETHROW_ERR(hr); 
// Get the appropriate fields 
hr =  adoRsBalance->get_Fields(&pFields); 
RETHROW_ERR(hr); 
 
// Get the appropriate field 
CComVariant vField = L"Balance"; 
CComVariant vBalance; 
hr = pFields->get_Item (vField, &pField) ; 
RETHROW_ERR(hr); 
hr = pField->get_Value (&vBalance) ; 
RETHROW_ERR(hr); 
 
// Check for overdraw, then prepare return string 
if (vBalance.lVal < 0) { 
 
TCHAR szBuffer2 [512]; 
wsprintf (szBuffer2, _T("Error. Account %ld would be overdrawn by %ld.  Balance is still %ld"), 
lAccount, vBalance.lVal, vBalance.lVal - lAmount); 
THROW_STR ( szBuffer2 ); 
} 
 
TCHAR szBuffer3 [512]; 
wsprintf (szBuffer3, _T("%s account %ld, balance is $%ld. (VC++)"), 
((lAmount >= 0) ? _T("Credit to") : _T("Debit from")), lAccount, vBalance.lVal); 
*pbstrResult = TCHAR2BSTR (szBuffer3); 
 
// Resource cleanup 
if (pField) pField->Release(); 
if (pFields) pFields->Release(); 
if (adoRsBalance) adoRsBalance->Release(); 
if (adoCoConnection) adoCoConnection->Release(); 
 
// We are finished and happy 
pObjectContext->SetComplete(); 
 
 
} catch (HRESULT hr) { 
 
// 
//ErrorInfo is saved here because the following ADO cleanup code  
//may clear it. 
// 
IErrorInfo * pErrorInfo = NULL; 
GetErrorInfo(NULL, &pErrorInfo); 
 
if (pField)pField->Release(); 
if (pFields) pFields->Release(); 
if (adoRsBalance) adoRsBalance->Release(); 
if (adoCoConnection) adoCoConnection->Release(); 
 
// Fill in error information 
switch (lErrFlag) { 
 
// Unknown error occurred in this object 
case (0): 
TCHAR szErr [512]; 
wsprintf (szErr, _T("Error 0x%x from CAccount calling %s."), hr, pErrMsg); 
pErrMsg = szErr; 
// Fall through 
 
// An application error occurred in this object 
case (1): 
// 
//we are going to put our own error in TLS, so if there is one there, clear it 
// 
if (pErrorInfo) 
pErrorInfo -> Release(); 
 
AtlReportError( CLSID_CAccount, pErrMsg, IID_IAccount, hr); 
break; 
case (2): // ADO error 
{ 
// 
//put the error back in TLS 
// 
SetErrorInfo(NULL, pErrorInfo); 
 
} 
break; 
// Will never reach here 
default: 
break; 
} 
 
// Indicate our unhappiness 
if (pObjectContext) 
pObjectContext->SetAbort(); 
 
} 
 
if (pObjectContext)pObjectContext->Release(); 
 
return hr; 
}