/*
Module?:?SERIALPORT.CPP
Purpose:?Implementation?for?an?MFC?wrapper?class?for?serial?ports
Created:?PJN?/?31-05-1999
History:?PJN?/?03-06-1999?1.?Fixed?problem?with?code?using?CancelIo?which?does?not?exist?on?95.
??????????????????????????2.?Fixed?leaks?which?can?occur?in?sample?app?when?an?exception?is?thrown
?????????PJN?/?16-06-1999?1.?Fixed?a?bug?whereby?CString::ReleaseBuffer?was?not?being?called?in?
?????????????????????????????CSerialException::GetErrorMessage
?????????PJN?/?29-09-1999?1.?Fixed?a?simple?copy?and?paste?bug?in?CSerialPort::SetDTR

Copyright?（c）?1999?by?PJ?Naughter.??
All?rights?reserved.

*/

/////////////////////////////////??Includes??//////////////////////////////////
#include?“stdafx.h“
#include?“serialport.h“
#include?“winerror.h“




/////////////////////////////////?defines?/////////////////////////////////////

#ifdef?_DEBUG
#define?new?DEBUG_NEW
#undef?THIS_FILE
static?char?THIS_FILE[]?=?__FILE__;
#endif




////////////////////////////////?Implementation?///////////////////////////////



//Class?which?handles?CancelIo?function?which?must?be?constructed?at?run?time
//since?it?is?not?imeplemented?on?NT?3.51?or?Windows?95.?To?avoid?the?loader
//bringing?up?a?message?such?as?“Failed?to?load?due?to?missing?export...“?the
//function?is?constructed?using?GetProcAddress.?The?CSerialPort::CancelIo?
//function?then?checks?to?see?if?the?function?pointer?is?NULL?and?if?it?is?it?
//throws?an?exception?using?the?error?code?ERROR_CALL_NOT_IMPLEMENTED?which
//is?what?95?would?have?done?if?it?had?implemented?a?stub?for?it?in?the?first
//place?!!

class?_SERIAL_PORT_DATA
{
public:
//Constructors?/Destructors
??_SERIAL_PORT_DATA（）;
??~_SERIAL_PORT_DATA（）;

??HINSTANCE?m_hKernel32;
??typedef?BOOL?（CANCELIO）（HANDLE）;
??typedef?CANCELIO*?LPCANCELIO;
??LPCANCELIO?m_lpfnCancelIo;
};

_SERIAL_PORT_DATA::_SERIAL_PORT_DATA（）
{
??m_hKernel32?=?LoadLibrary（_T（“KERNEL32.DLL“））;
??VERIFY（m_hKernel32?!=?NULL）;
??m_lpfnCancelIo?=?（LPCANCELIO）?GetProcAddress（m_hKernel32?“CancelIo“）;
}

_SERIAL_PORT_DATA::~_SERIAL_PORT_DATA（）
{
??FreeLibrary（m_hKernel32）;
??m_hKernel32?=?NULL;
}


//The?local?variable?which?handle?the?function?pointers

_SERIAL_PORT_DATA?_SerialPortData;




//////////?Exception?handling?code

void?AfxThrowSerialException（DWORD?dwError?/*?=?0?*/）
{
	if?（dwError?==?0）
		dwError?=?::GetLastError（）;

	CSerialException*?pException?=?new?CSerialException（dwError）;

	TRACE（_T（“Warning:?throwing?CSerialException?for?error?%d\n“）?dwError）;
	THROW（pException）;
}

BOOL?CSerialException::GetErrorMessage（LPTSTR?pstrError?UINT?nMaxError?PUINT?pnHelpContext）
{
	ASSERT（pstrError?!=?NULL?&&?AfxIsValidString（pstrError?nMaxError））;

	if?（pnHelpContext?!=?NULL）
		*pnHelpContext?=?0;

	LPTSTR?lpBuffer;
	BOOL?bRet?=?FormatMessage（FORMAT_MESSAGE_ALLOCATE_BUFFER?|?FORMAT_MESSAGE_FROM_SYSTEM
			??????????????????????NULL??m_dwError?MAKELANGID（

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----

?????文件???????4238??1999-05-31?23:48??serialport\serialport.h

?????文件??????19021??1999-09-29?21:09??serialport\serialport.cpp

?????目錄??????????0??2008-07-22?15:54??serialport

-----------?---------??----------?-----??----

????????????????23259????????????????????3