CSerialPort串口类最新修正版(解决关闭死锁问题)2014-01-11

这是一份优秀的类文件，好多的地方值得我们学习，具体在多线程，事件，自定义消息，类的封装方面等等。
Remon提供的串口类网址为： http://codeguru.earthweb.com/network/serialport.shtml，
由于已经运行十几年了，原文的问答部分列出来这么多年来的问题，经过网友们的总结，补充和修改原来代码后，整理出一份相对比较完美的代码。

 

此外还附带一份小项目的源代码，它超越了串口助手，给人一种耳目一新的感觉。亮点如下：

1. 它解决了串口关闭时出现死锁不响应问题，可以直接用到开发的项目上。
2. 并且是扩展了的串口助手，具有通信协议编辑和使用功能，
3. 软件升级检测，值得做软件升级例子使用。
4. 最重要的是源代码很不错，很值得大家去研究。

   分享给需要的朋友们，有问题，可以在留言，以便做进一步修正。

VC串口修正类应用的小项目下载地址：http://download.csdn.net/detail/liquanhai/3763088

2014-01-11补充说明：

最新的CSerialPort类的下载地址在：https://github.com/liquanhai/CSerialPort

 



头文件CSerialPort.h如下：

 

[cpp] view plaincopyprint?在CODE上查看代码片派生到我的代码片
  1. /* 
  2. **  FILENAME            CSerialPort.h 
  3. ** 
  4. **  PURPOSE             This class can read, write and watch one serial port. 
  5. **                      It sends messages to its owner when something happends on the port 
  6. **                      The class creates a thread for reading and writing so the main 
  7. **                      program is not blocked. 
  8. ** 
  9. **  CREATION DATE       15-09-1997 
  10. **  LAST MODIFICATION   12-11-1997 
  11. ** 
  12. **  AUTHOR              Remon Spekreijse 
  13. ** 
  14. ** 
  15. ************************************************************************************ 
  16. **  author: mrlong date:2007-12-25 
  17. ** 
  18. **  改进 
  19. **    1) 增加ClosePort 
  20. **    2) 增加 writetoProt() 两个方法 
  21. **    3) 增加 SendData 与 RecvData 方法 
  22. ************************************************************************************** 
  23. *************************************************************************************** 
  24. **  author：liquanhai date:2011-11-04 
  25. **  改进 
  26. **    1）增加 ClosePort中交出控制权，防止死锁问题 
  27. **    2) 增加 ReceiveChar中防止线程死锁 
  28.  */  
  29.   
  30. #ifndef __SERIALPORT_H__   
  31. #define __SERIALPORT_H__   
  32.   
  33. #define WM_COMM_BREAK_DETECTED      WM_USER+1   // A break was detected on input.   
  34. #define WM_COMM_CTS_DETECTED        WM_USER+2   // The CTS (clear-to-send) signal changed state.    
  35. #define WM_COMM_DSR_DETECTED        WM_USER+3   // The DSR (data-set-ready) signal changed state.    
  36. #define WM_COMM_ERR_DETECTED        WM_USER+4   // A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY.    
  37. #define WM_COMM_RING_DETECTED       WM_USER+5   // A ring indicator was detected.    
  38. #define WM_COMM_RLSD_DETECTED       WM_USER+6   // The RLSD (receive-line-signal-detect) signal changed state.    
  39. #define WM_COMM_RXCHAR              WM_USER+7   // A character was received and placed in the input buffer.    
  40. #define WM_COMM_RXFLAG_DETECTED     WM_USER+8   // The event character was received and placed in the input buffer.     
  41. #define WM_COMM_TXEMPTY_DETECTED    WM_USER+9   // The last character in the output buffer was sent.     
  42.   
  43. class CSerialPort  
  44. {                                                          
  45. public:  
  46.     // contruction and destruction   
  47.     CSerialPort();  
  48.     virtual     ~CSerialPort();  
  49.   
  50.     // port initialisation                                             
  51.     BOOL        InitPort(CWnd* pPortOwner, UINT portnr = 1, UINT baud = 19200,   
  52.                 char parity = 'N', UINT databits = 8, UINT stopsbits = 1,   
  53.                 DWORD dwCommEvents = EV_RXCHAR | EV_CTS, UINT nBufferSize = 512,  
  54.               
  55.                 DWORD ReadIntervalTimeout = 1000,  
  56.                 DWORD ReadTotalTimeoutMultiplier = 1000,  
  57.                 DWORD ReadTotalTimeoutConstant = 1000,  
  58.                 DWORD WriteTotalTimeoutMultiplier = 1000,  
  59.                 DWORD WriteTotalTimeoutConstant = 1000);  
  60.   
  61.     // start/stop comm watching   
  62.     BOOL        StartMonitoring();  
  63.     BOOL        RestartMonitoring();  
  64.     BOOL        StopMonitoring();  
  65.   
  66.     DWORD       GetWriteBufferSize();  
  67.     DWORD       GetCommEvents();  
  68.     DCB         GetDCB();  
  69.   
  70.     void        WriteToPort(char* string);  
  71.     void        WriteToPort(char* string,int n); // add by mrlong 2007-12-25   
  72.     void        WriteToPort(LPCTSTR string);     // add by mrlong 2007-12-25   
  73.     void        WriteToPort(BYTE* Buffer, int n);// add by mrlong   
  74.     void        ClosePort();                     // add by mrlong 2007-12-2     
  75.   
  76.     void SendData(LPCTSTR lpszData, const int nLength);   //串口发送函数 by mrlong 2008-2-15   
  77.     BOOL RecvData(LPTSTR lpszData, const int nSize);      //串口接收函数 by mrlong 2008-2-15   
  78.   
  79. protected:  
  80.     // protected memberfunctions   
  81.     void        ProcessErrorMessage(char* ErrorText);  
  82.     static UINT CommThread(LPVOID pParam);  
  83.     static void ReceiveChar(CSerialPort* port, COMSTAT comstat);  
  84.     static void WriteChar(CSerialPort* port);  
  85.   
  86.     // thread   
  87.     CWinThread*         m_Thread;  
  88.   
  89.     // synchronisation objects   
  90.     CRITICAL_SECTION    m_csCommunicationSync;  
  91.     BOOL                m_bThreadAlive;  
  92.   
  93.     // handles   
  94.     HANDLE              m_hShutdownEvent;  //stop发生的事件   
  95.     HANDLE              m_hComm;           // read     
  96.     HANDLE              m_hWriteEvent;     // write   
  97.   
  98.     // Event array.    
  99.     // One element is used for each event. There are two event handles for each port.   
  100.     // A Write event and a receive character event which is located in the overlapped structure (m_ov.hEvent).   
  101.     // There is a general shutdown when the port is closed.    
  102.     HANDLE              m_hEventArray[3];  
  103.   
  104.     // structures   
  105.     OVERLAPPED          m_ov;  
  106.     COMMTIMEOUTS        m_CommTimeouts;  
  107.     DCB                 m_dcb;  
  108.   
  109.     // owner window   
  110.     CWnd*               m_pOwner;  
  111.   
  112.     // misc   
  113.     UINT                m_nPortNr;        //?????   
  114.     char*               m_szWriteBuffer;  
  115.     DWORD               m_dwCommEvents;  
  116.     DWORD               m_nWriteBufferSize;  
  117.   
  118.     int                 m_nWriteSize; //add by mrlong 2007-12-25   
  119. };  
  120.   
  121. #endif __SERIALPORT_H__  
/*
**	FILENAME			CSerialPort.h
**
**	PURPOSE				This class can read, write and watch one serial port.
**						It sends messages to its owner when something happends on the port
**						The class creates a thread for reading and writing so the main
**						program is not blocked.
**
**	CREATION DATE		15-09-1997
**	LAST MODIFICATION	12-11-1997
**
**	AUTHOR				Remon Spekreijse
**
**
************************************************************************************
**  author: mrlong date:2007-12-25
**
**  改进
**    1) 增加ClosePort
**    2) 增加 writetoProt() 两个方法
**    3) 增加 SendData 与 RecvData 方法
**************************************************************************************
***************************************************************************************
**  author：liquanhai date:2011-11-04
**  改进
**    1）增加 ClosePort中交出控制权，防止死锁问题
**    2) 增加 ReceiveChar中防止线程死锁
 */

#ifndef __SERIALPORT_H__
#define __SERIALPORT_H__

#define WM_COMM_BREAK_DETECTED		WM_USER+1	// A break was detected on input.
#define WM_COMM_CTS_DETECTED		WM_USER+2	// The CTS (clear-to-send) signal changed state. 
#define WM_COMM_DSR_DETECTED		WM_USER+3	// The DSR (data-set-ready) signal changed state. 
#define WM_COMM_ERR_DETECTED		WM_USER+4	// A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY. 
#define WM_COMM_RING_DETECTED		WM_USER+5	// A ring indicator was detected. 
#define WM_COMM_RLSD_DETECTED		WM_USER+6	// The RLSD (receive-line-signal-detect) signal changed state. 
#define WM_COMM_RXCHAR				WM_USER+7	// A character was received and placed in the input buffer. 
#define WM_COMM_RXFLAG_DETECTED		WM_USER+8	// The event character was received and placed in the input buffer.  
#define WM_COMM_TXEMPTY_DETECTED	WM_USER+9	// The last character in the output buffer was sent.  

class CSerialPort
{														 
public:
	// contruction and destruction
	CSerialPort();
	virtual		~CSerialPort();

	// port initialisation											
	BOOL		InitPort(CWnd* pPortOwner, UINT portnr = 1, UINT baud = 19200, 
				char parity = 'N', UINT databits = 8, UINT stopsbits = 1, 
				DWORD dwCommEvents = EV_RXCHAR | EV_CTS, UINT nBufferSize = 512,
			
				DWORD ReadIntervalTimeout = 1000,
				DWORD ReadTotalTimeoutMultiplier = 1000,
				DWORD ReadTotalTimeoutConstant = 1000,
				DWORD WriteTotalTimeoutMultiplier = 1000,
				DWORD WriteTotalTimeoutConstant = 1000);

	// start/stop comm watching
	BOOL		StartMonitoring();
	BOOL		RestartMonitoring();
	BOOL		StopMonitoring();

	DWORD		GetWriteBufferSize();
	DWORD		GetCommEvents();
	DCB			GetDCB();

	void		WriteToPort(char* string);
	void        WriteToPort(char* string,int n); // add by mrlong 2007-12-25
	void		WriteToPort(LPCTSTR string);     // add by mrlong 2007-12-25
	void        WriteToPort(BYTE* Buffer, int n);// add by mrlong
	void        ClosePort();                     // add by mrlong 2007-12-2  

	void SendData(LPCTSTR lpszData, const int nLength);   //串口发送函数 by mrlong 2008-2-15
	BOOL RecvData(LPTSTR lpszData, const int nSize);      //串口接收函数 by mrlong 2008-2-15

protected:
	// protected memberfunctions
	void		ProcessErrorMessage(char* ErrorText);
	static UINT	CommThread(LPVOID pParam);
	static void	ReceiveChar(CSerialPort* port, COMSTAT comstat);
	static void	WriteChar(CSerialPort* port);

	// thread
	CWinThread*			m_Thread;

	// synchronisation objects
	CRITICAL_SECTION	m_csCommunicationSync;
	BOOL				m_bThreadAlive;

	// handles
	HANDLE				m_hShutdownEvent;  //stop发生的事件
	HANDLE				m_hComm;           // read  
	HANDLE				m_hWriteEvent;     // write

	// Event array. 
	// One element is used for each event. There are two event handles for each port.
	// A Write event and a receive character event which is located in the overlapped structure (m_ov.hEvent).
	// There is a general shutdown when the port is closed. 
	HANDLE				m_hEventArray[3];

	// structures
	OVERLAPPED			m_ov;
	COMMTIMEOUTS		m_CommTimeouts;
	DCB					m_dcb;

	// owner window
	CWnd*				m_pOwner;

	// misc
	UINT				m_nPortNr;        //?????
	char*				m_szWriteBuffer;
	DWORD				m_dwCommEvents;
	DWORD				m_nWriteBufferSize;

	int                 m_nWriteSize; //add by mrlong 2007-12-25
};

#endif __SERIALPORT_H__



 

源文件cpp文件如下：

 

[cpp] view plaincopyprint?在CODE上查看代码片派生到我的代码片
  1. /* 
  2. **  FILENAME            CSerialPort.cpp 
  3. ** 
  4. **  PURPOSE             This class can read, write and watch one serial port. 
  5. **                      It sends messages to its owner when something happends on the port 
  6. **                      The class creates a thread for reading and writing so the main 
  7. **                      program is not blocked. 
  8. ** 
  9. **  CREATION DATE       15-09-1997 
  10. **  LAST MODIFICATION   12-11-1997 
  11. ** 
  12. **  AUTHOR              Remon Spekreijse 
  13. ** 
  14. ** 
  15. */  
  16.   
  17. #include "stdafx.h"   
  18. #include "SerialPort.h"   
  19.   
  20. #include <assert.h>   
  21.    
  22. //   
  23. // Constructor   
  24. //   
  25. CSerialPort::CSerialPort()  
  26. {  
  27.     m_hComm = NULL;  
  28.   
  29.     // initialize overlapped structure members to zero   
  30.     m_ov.Offset = 0;  
  31.     m_ov.OffsetHigh = 0;  
  32.   
  33.     // create events   
  34.     m_ov.hEvent = NULL;  
  35.     m_hWriteEvent = NULL;  
  36.     m_hShutdownEvent = NULL;  
  37.   
  38.     m_szWriteBuffer = NULL;  
  39.   
  40.     m_bThreadAlive = FALSE;  
  41.     m_nWriteSize = 1;  
  42. }  
  43.   
  44. //   
  45. // Delete dynamic memory   
  46. //   
  47. CSerialPort::~CSerialPort()  
  48. {  
  49.     do  
  50.     {  
  51.         SetEvent(m_hShutdownEvent);  
  52.     } while (m_bThreadAlive);  
  53.   
  54.     if (m_hComm != NULL)  
  55.     {  
  56.         CloseHandle(m_hComm);  
  57.         m_hComm = NULL;  
  58.     }  
  59.     // Close Handles     
  60.     if(m_hShutdownEvent!=NULL)  
  61.         CloseHandle( m_hShutdownEvent);   
  62.     if(m_ov.hEvent!=NULL)  
  63.         CloseHandle( m_ov.hEvent );   
  64.     if(m_hWriteEvent!=NULL)  
  65.         CloseHandle( m_hWriteEvent );   
  66.   
  67.     TRACE("Thread ended\n");  
  68.   
  69.     delete [] m_szWriteBuffer;  
  70. }  
  71.   
  72. //   
  73. // Initialize the port. This can be port 1 to 4.   
  74. //   
  75. //   
  76. //parity:   
  77. //  n=none   
  78. //  e=even   
  79. //  o=odd   
  80. //  m=mark   
  81. //  s=space   
  82. //data:   
  83. //  5,6,7,8   
  84. //stop:   
  85. //  1,1.5,2    
  86. //   
  87. BOOL CSerialPort::InitPort(CWnd* pPortOwner,    // the owner (CWnd) of the port (receives message)   
  88.                            UINT  portnr,        // portnumber (1..4)   
  89.                            UINT  baud,          // baudrate   
  90.                            char  parity,        // parity    
  91.                            UINT  databits,      // databits    
  92.                            UINT  stopbits,      // stopbits    
  93.                            DWORD dwCommEvents,  // EV_RXCHAR, EV_CTS etc   
  94.                            UINT  writebuffersize,// size to the writebuffer   
  95.                              
  96.                            DWORD   ReadIntervalTimeout,  
  97.                            DWORD   ReadTotalTimeoutMultiplier,  
  98.                            DWORD   ReadTotalTimeoutConstant,  
  99.                            DWORD   WriteTotalTimeoutMultiplier,  
  100.                            DWORD   WriteTotalTimeoutConstant )    
  101.   
  102. {  
  103.     assert(portnr > 0 && portnr < 5);  
  104.     assert(pPortOwner != NULL);  
  105.   
  106.     // if the thread is alive: Kill   
  107.     if (m_bThreadAlive)  
  108.     {  
  109.         do  
  110.         {  
  111.             SetEvent(m_hShutdownEvent);  
  112.         } while (m_bThreadAlive);  
  113.         TRACE("Thread ended\n");  
  114.     }  
  115.   
  116.     // create events   
  117.     if (m_ov.hEvent != NULL)  
  118.         ResetEvent(m_ov.hEvent);  
  119.     else  
  120.         m_ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);  
  121.   
  122.     if (m_hWriteEvent != NULL)  
  123.         ResetEvent(m_hWriteEvent);  
  124.     else  
  125.         m_hWriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL);  
  126.       
  127.     if (m_hShutdownEvent != NULL)  
  128.         ResetEvent(m_hShutdownEvent);  
  129.     else  
  130.         m_hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL);  
  131.   
  132.     // initialize the event objects   
  133.     m_hEventArray[0] = m_hShutdownEvent;    // highest priority   
  134.     m_hEventArray[1] = m_ov.hEvent;  
  135.     m_hEventArray[2] = m_hWriteEvent;  
  136.   
  137.     // initialize critical section   
  138.     InitializeCriticalSection(&m_csCommunicationSync);  
  139.       
  140.     // set buffersize for writing and save the owner   
  141.     m_pOwner = pPortOwner;  
  142.   
  143.     if (m_szWriteBuffer != NULL)  
  144.         delete [] m_szWriteBuffer;  
  145.     m_szWriteBuffer = new char[writebuffersize];  
  146.   
  147.     m_nPortNr = portnr;  
  148.   
  149.     m_nWriteBufferSize = writebuffersize;  
  150.     m_dwCommEvents = dwCommEvents;  
  151.   
  152.     BOOL bResult = FALSE;  
  153.     char *szPort = new char[50];  
  154.     char *szBaud = new char[50];  
  155.   
  156.     // now it critical!   
  157.     EnterCriticalSection(&m_csCommunicationSync);  
  158.   
  159.     // if the port is already opened: close it   
  160.     if (m_hComm != NULL)  
  161.     {  
  162.         CloseHandle(m_hComm);  
  163.         m_hComm = NULL;  
  164.     }  
  165.   
  166.     // prepare port strings   
  167.     sprintf(szPort, "COM%d", portnr);  
  168.     // stop is index 0 = 1 1=1.5 2=2   
  169.     int mystop;  
  170.     int myparity;  
  171.     switch(stopbits)  
  172.     {  
  173.         case 0:  
  174.             mystop = ONESTOPBIT;  
  175.             break;  
  176.         case 1:  
  177.             mystop = ONE5STOPBITS;  
  178.             break;  
  179.         case 2:  
  180.             mystop = TWOSTOPBITS;  
  181.             break;  
  182.     }  
  183.     myparity = 0;  
  184.     switch(parity)  
  185.     {  
  186.         case 'N':  
  187.             myparity = 0;  
  188.             break;  
  189.         case 'E':  
  190.             myparity = 1;  
  191.             break;  
  192.         case 'O':  
  193.             myparity = 2;  
  194.             break;  
  195.         case 'M':  
  196.             myparity = 3;  
  197.             break;  
  198.         case 'S':  
  199.             myparity = 4;  
  200.             break;  
  201.     }  
  202.     sprintf(szBaud, "baud=%d parity=%c data=%d stop=%d", baud, parity, databits, mystop);  
  203.   
  204.     // get a handle to the port   
  205.     m_hComm = CreateFile(szPort,                        // communication port string (COMX)   
  206.                          GENERIC_READ | GENERIC_WRITE,  // read/write types   
  207.                          0,                             // comm devices must be opened with exclusive access   
  208.                          NULL,                          // no security attributes   
  209.                          OPEN_EXISTING,                 // comm devices must use OPEN_EXISTING   
  210.                          FILE_FLAG_OVERLAPPED,          // Async I/O   
  211.                          0);                            // template must be 0 for comm devices   
  212.   
  213.     if (m_hComm == INVALID_HANDLE_VALUE)  
  214.     {  
  215.         // port not found   
  216.         delete [] szPort;  
  217.         delete [] szBaud;  
  218.   
  219.         return FALSE;  
  220.     }  
  221.   
  222.     // set the timeout values   
  223.     m_CommTimeouts.ReadIntervalTimeout         = ReadIntervalTimeout * 1000;  
  224.     m_CommTimeouts.ReadTotalTimeoutMultiplier  = ReadTotalTimeoutMultiplier * 1000;  
  225.     m_CommTimeouts.ReadTotalTimeoutConstant    = ReadTotalTimeoutConstant * 1000;  
  226.     m_CommTimeouts.WriteTotalTimeoutMultiplier = WriteTotalTimeoutMultiplier * 1000;  
  227.     m_CommTimeouts.WriteTotalTimeoutConstant   = WriteTotalTimeoutConstant * 1000;  
  228.   
  229.     // configure   
  230.     if (SetCommTimeouts(m_hComm, &m_CommTimeouts))  
  231.     {                            
  232.         if (SetCommMask(m_hComm, dwCommEvents))  
  233.         {  
  234.             if (GetCommState(m_hComm, &m_dcb))  
  235.             {  
  236.                 m_dcb.EvtChar = 'q';  
  237.                 m_dcb.fRtsControl = RTS_CONTROL_ENABLE;     // set RTS bit high!   
  238.                 m_dcb.BaudRate = baud;  // add by mrlong   
  239.                 m_dcb.Parity   = myparity;  
  240.                 m_dcb.ByteSize = databits;  
  241.                 m_dcb.StopBits = mystop;  
  242.                           
  243.                 //if (BuildCommDCB(szBaud, &m_dcb))   
  244.                 //{   
  245.                     if (SetCommState(m_hComm, &m_dcb))  
  246.                         ; // normal operation... continue   
  247.                     else  
  248.                         ProcessErrorMessage("SetCommState()");  
  249.                 //}   
  250.                 //else   
  251.                 //  ProcessErrorMessage("BuildCommDCB()");   
  252.             }  
  253.             else  
  254.                 ProcessErrorMessage("GetCommState()");  
  255.         }  
  256.         else  
  257.             ProcessErrorMessage("SetCommMask()");  
  258.     }  
  259.     else  
  260.         ProcessErrorMessage("SetCommTimeouts()");  
  261.   
  262.     delete [] szPort;  
  263.     delete [] szBaud;  
  264.   
  265.     // flush the port   
  266.     PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);  
  267.   
  268.     // release critical section   
  269.     LeaveCriticalSection(&m_csCommunicationSync);  
  270.   
  271.     TRACE("Initialisation for communicationport %d completed.\nUse Startmonitor to communicate.\n", portnr);  
  272.   
  273.     return TRUE;  
  274. }  
  275.   
  276. //   
  277. //  The CommThread Function.   
  278. //   
  279. UINT CSerialPort::CommThread(LPVOID pParam)  
  280. {  
  281.     // Cast the void pointer passed to the thread back to   
  282.     // a pointer of CSerialPort class   
  283.     CSerialPort *port = (CSerialPort*)pParam;  
  284.       
  285.     // Set the status variable in the dialog class to   
  286.     // TRUE to indicate the thread is running.   
  287.     port->m_bThreadAlive = TRUE;   
  288.           
  289.     // Misc. variables   
  290.     DWORD BytesTransfered = 0;   
  291.     DWORD Event = 0;  
  292.     DWORD CommEvent = 0;  
  293.     DWORD dwError = 0;  
  294.     COMSTAT comstat;  
  295.     BOOL  bResult = TRUE;  
  296.           
  297.     // Clear comm buffers at startup   
  298.     if (port->m_hComm)       // check if the port is opened   
  299.         PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);  
  300.   
  301.     // begin forever loop.  This loop will run as long as the thread is alive.   
  302.     for (;;)   
  303.     {   
  304.   
  305.         // Make a call to WaitCommEvent().  This call will return immediatly   
  306.         // because our port was created as an async port (FILE_FLAG_OVERLAPPED   
  307.         // and an m_OverlappedStructerlapped structure specified).  This call will cause the    
  308.         // m_OverlappedStructerlapped element m_OverlappedStruct.hEvent, which is part of the m_hEventArray to    
  309.         // be placed in a non-signeled state if there are no bytes available to be read,   
  310.         // or to a signeled state if there are bytes available.  If this event handle    
  311.         // is set to the non-signeled state, it will be set to signeled when a    
  312.         // character arrives at the port.   
  313.   
  314.         // we do this for each port!   
  315.   
  316.         bResult = WaitCommEvent(port->m_hComm, &Event, &port->m_ov);  
  317.   
  318.         if (!bResult)    
  319.         {   
  320.             // If WaitCommEvent() returns FALSE, process the last error to determin   
  321.             // the reason..   
  322.             switch (dwError = GetLastError())   
  323.             {   
  324.             case ERROR_IO_PENDING:    
  325.                 {   
  326.                     // This is a normal return value if there are no bytes   
  327.                     // to read at the port.   
  328.                     // Do nothing and continue   
  329.                     break;  
  330.                 }  
  331.             case 87:  
  332.                 {  
  333.                     // Under Windows NT, this value is returned for some reason.   
  334.                     // I have not investigated why, but it is also a valid reply   
  335.                     // Also do nothing and continue.   
  336.                     break;  
  337.                 }  
  338.             default:  
  339.                 {  
  340.                     // All other error codes indicate a serious error has   
  341.                     // occured.  Process this error.   
  342.                     port->ProcessErrorMessage("WaitCommEvent()");  
  343.                     break;  
  344.                 }  
  345.             }  
  346.         }  
  347.         else  
  348.         {  
  349.             // If WaitCommEvent() returns TRUE, check to be sure there are   
  350.             // actually bytes in the buffer to read.     
  351.             //   
  352.             // If you are reading more than one byte at a time from the buffer    
  353.             // (which this program does not do) you will have the situation occur    
  354.             // where the first byte to arrive will cause the WaitForMultipleObjects()    
  355.             // function to stop waiting.  The WaitForMultipleObjects() function    
  356.             // resets the event handle in m_OverlappedStruct.hEvent to the non-signelead state   
  357.             // as it returns.     
  358.             //   
  359.             // If in the time between the reset of this event and the call to    
  360.             // ReadFile() more bytes arrive, the m_OverlappedStruct.hEvent handle will be set again   
  361.             // to the signeled state. When the call to ReadFile() occurs, it will    
  362.             // read all of the bytes from the buffer, and the program will   
  363.             // loop back around to WaitCommEvent().   
  364.             //    
  365.             // At this point you will be in the situation where m_OverlappedStruct.hEvent is set,   
  366.             // but there are no bytes available to read.  If you proceed and call   
  367.             // ReadFile(), it will return immediatly due to the async port setup, but   
  368.             // GetOverlappedResults() will not return until the next character arrives.   
  369.             //   
  370.             // It is not desirable for the GetOverlappedResults() function to be in    
  371.             // this state.  The thread shutdown event (event 0) and the WriteFile()   
  372.             // event (Event2) will not work if the thread is blocked by GetOverlappedResults().   
  373.             //   
  374.             // The solution to this is to check the buffer with a call to ClearCommError().   
  375.             // This call will reset the event handle, and if there are no bytes to read   
  376.             // we can loop back through WaitCommEvent() again, then proceed.   
  377.             // If there are really bytes to read, do nothing and proceed.   
  378.           
  379.             bResult = ClearCommError(port->m_hComm, &dwError, &comstat);  
  380.   
  381.             if (comstat.cbInQue == 0)  
  382.                 continue;  
  383.         }   // end if bResult   
  384.   
  385.         // Main wait function.  This function will normally block the thread   
  386.         // until one of nine events occur that require action.   
  387.         Event = WaitForMultipleObjects(3, port->m_hEventArray, FALSE, INFINITE);  
  388.   
  389.         switch (Event)  
  390.         {  
  391.         case 0:  
  392.             {  
  393.                 // Shutdown event.  This is event zero so it will be   
  394.                 // the higest priority and be serviced first.   
  395.   
  396.                 port->m_bThreadAlive = FALSE;  
  397.                   
  398.                 // Kill this thread.  break is not needed, but makes me feel better.   
  399.                 AfxEndThread(100);  
  400.                 break;  
  401.             }  
  402.         case 1: // read event   
  403.             {  
  404.                 GetCommMask(port->m_hComm, &CommEvent);  
  405.                 if (CommEvent & EV_RXCHAR) //接收到字符，并置于输入缓冲区中    
  406.                     ReceiveChar(port, comstat);  
  407.                   
  408.                 if (CommEvent & EV_CTS) //CTS信号状态发生变化   
  409.                     ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_CTS_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);  
  410.                 if (CommEvent & EV_RXFLAG) //接收到事件字符，并置于输入缓冲区中    
  411.                     ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RXFLAG_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);  
  412.                 if (CommEvent & EV_BREAK)  //输入中发生中断   
  413.                     ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_BREAK_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);  
  414.                 if (CommEvent & EV_ERR) //发生线路状态错误，线路状态错误包括CE_FRAME,CE_OVERRUN和CE_RXPARITY    
  415.                     ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_ERR_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);  
  416.                 if (CommEvent & EV_RING) //检测到振铃指示   
  417.                     ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RING_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);  
  418.                       
  419.                 break;  
  420.             }    
  421.         case 2: // write event   
  422.             {  
  423.                 // Write character event from port   
  424.                 WriteChar(port);  
  425.                 break;  
  426.             }  
  427.   
  428.         } // end switch   
  429.   
  430.     } // close forever loop   
  431.   
  432.     return 0;  
  433. }  
  434.   
  435. //   
  436. // start comm watching   
  437. //   
  438. BOOL CSerialPort::StartMonitoring()  
  439. {  
  440.     if (!(m_Thread = AfxBeginThread(CommThread, this)))  
  441.         return FALSE;  
  442.     TRACE("Thread started\n");  
  443.     return TRUE;      
  444. }  
  445.   
  446. //   
  447. // Restart the comm thread   
  448. //   
  449. BOOL CSerialPort::RestartMonitoring()  
  450. {  
  451.     TRACE("Thread resumed\n");  
  452.     m_Thread->ResumeThread();  
  453.     return TRUE;      
  454. }  
  455.   
  456.   
  457. //   
  458. // Suspend the comm thread   
  459. //   
  460. BOOL CSerialPort::StopMonitoring()  
  461. {  
  462.     TRACE("Thread suspended\n");  
  463.     m_Thread->SuspendThread();   
  464.     return TRUE;      
  465. }  
  466.   
  467.   
  468. //   
  469. // If there is a error, give the right message   
  470. //   
  471. void CSerialPort::ProcessErrorMessage(char* ErrorText)  
  472. {  
  473.     char *Temp = new char[200];  
  474.       
  475.     LPVOID lpMsgBuf;  
  476.   
  477.     FormatMessage(   
  478.         FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,  
  479.         NULL,  
  480.         GetLastError(),  
  481.         MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language   
  482.         (LPTSTR) &lpMsgBuf,  
  483.         0,  
  484.         NULL   
  485.     );  
  486.   
  487.     sprintf(Temp, "WARNING:  %s Failed with the following error: \n%s\nPort: %d\n", (char*)ErrorText, lpMsgBuf, m_nPortNr);   
  488.     MessageBox(NULL, Temp, "Application Error", MB_ICONSTOP);  
  489.   
  490.     LocalFree(lpMsgBuf);  
  491.     delete[] Temp;  
  492. }  
  493.   
  494. //   
  495. // Write a character.   
  496. //   
  497. void CSerialPort::WriteChar(CSerialPort* port)  
  498. {  
  499.     BOOL bWrite = TRUE;  
  500.     BOOL bResult = TRUE;  
  501.   
  502.     DWORD BytesSent = 0;  
  503.     DWORD SendLen   = port->m_nWriteSize;  
  504.     ResetEvent(port->m_hWriteEvent);  
  505.   
  506.   
  507.     // Gain ownership of the critical section   
  508.     EnterCriticalSection(&port->m_csCommunicationSync);  
  509.   
  510.     if (bWrite)  
  511.     {  
  512.         // Initailize variables   
  513.         port->m_ov.Offset = 0;  
  514.         port->m_ov.OffsetHigh = 0;  
  515.        
  516.         // Clear buffer   
  517.         PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);  
  518.   
  519.         bResult = WriteFile(port->m_hComm,                           // Handle to COMM Port   
  520.                             port->m_szWriteBuffer,                   // Pointer to message buffer in calling finction   
  521.                             SendLen,    // add by mrlong   
  522.                             //strlen((char*)port->m_szWriteBuffer),  // Length of message to send   
  523.                             &BytesSent,                             // Where to store the number of bytes sent   
  524.                             &port->m_ov);                            // Overlapped structure   
  525.   
  526.         // deal with any error codes   
  527.         if (!bResult)    
  528.         {  
  529.             DWORD dwError = GetLastError();  
  530.             switch (dwError)  
  531.             {  
  532.                 case ERROR_IO_PENDING:  
  533.                     {  
  534.                         // continue to GetOverlappedResults()   
  535.                         BytesSent = 0;  
  536.                         bWrite = FALSE;  
  537.                         break;  
  538.                     }  
  539.                 default:  
  540.                     {  
  541.                         // all other error codes   
  542.                         port->ProcessErrorMessage("WriteFile()");  
  543.                     }  
  544.             }  
  545.         }   
  546.         else  
  547.         {  
  548.             LeaveCriticalSection(&port->m_csCommunicationSync);  
  549.         }  
  550.     } // end if(bWrite)   
  551.   
  552.     if (!bWrite)  
  553.     {  
  554.         bWrite = TRUE;  
  555.       
  556.         bResult = GetOverlappedResult(port->m_hComm, // Handle to COMM port    
  557.                                       &port->m_ov,       // Overlapped structure   
  558.                                       &BytesSent,       // Stores number of bytes sent   
  559.                                       TRUE);            // Wait flag   
  560.   
  561.         LeaveCriticalSection(&port->m_csCommunicationSync);  
  562.   
  563.         // deal with the error code    
  564.         if (!bResult)    
  565.         {  
  566.             port->ProcessErrorMessage("GetOverlappedResults() in WriteFile()");  
  567.         }     
  568.     } // end if (!bWrite)   
  569.   
  570.     // Verify that the data size send equals what we tried to send   
  571.     if (BytesSent != SendLen /*strlen((char*)port->m_szWriteBuffer)*/)  // add by    
  572.     {  
  573.         TRACE("WARNING: WriteFile() error.. Bytes Sent: %d; Message Length: %d\n", BytesSent, strlen((char*)port->m_szWriteBuffer));  
  574.     }  
  575. }  
  576.   
  577. //   
  578. // Character received. Inform the owner   
  579. //   
  580. void CSerialPort::ReceiveChar(CSerialPort* port, COMSTAT comstat)  
  581. {  
  582.     BOOL  bRead = TRUE;   
  583.     BOOL  bResult = TRUE;  
  584.     DWORD dwError = 0;  
  585.     DWORD BytesRead = 0;  
  586.     unsigned char RXBuff;  
  587.   
  588.     for (;;)   
  589.     {   
  590.              //add by liquanhai 2011-11-06  防止死锁   
  591.              if(WaitForSingleObject(port->m_hShutdownEvent,0)==WAIT_OBJECT_0)  
  592.                  return;  
  593.   
  594.                 // Gain ownership of the comm port critical section.   
  595.         // This process guarantees no other part of this program    
  596.         // is using the port object.    
  597.           
  598.         EnterCriticalSection(&port->m_csCommunicationSync);  
  599.   
  600.         // ClearCommError() will update the COMSTAT structure and   
  601.         // clear any other errors.   
  602.           
  603.         bResult = ClearCommError(port->m_hComm, &dwError, &comstat);  
  604.   
  605.         LeaveCriticalSection(&port->m_csCommunicationSync);  
  606.   
  607.         // start forever loop.  I use this type of loop because I   
  608.         // do not know at runtime how many loops this will have to   
  609.         // run. My solution is to start a forever loop and to   
  610.         // break out of it when I have processed all of the   
  611.         // data available.  Be careful with this approach and   
  612.         // be sure your loop will exit.   
  613.         // My reasons for this are not as clear in this sample    
  614.         // as it is in my production code, but I have found this    
  615.         // solutiion to be the most efficient way to do this.   
  616.           
  617.         if (comstat.cbInQue == 0)  
  618.         {  
  619.             // break out when all bytes have been read   
  620.             break;  
  621.         }  
  622.                           
  623.         EnterCriticalSection(&port->m_csCommunicationSync);  
  624.   
  625.         if (bRead)  
  626.         {  
  627.             bResult = ReadFile(port->m_hComm,        // Handle to COMM port    
  628.                                &RXBuff,             // RX Buffer Pointer   
  629.                                1,                   // Read one byte   
  630.                                &BytesRead,          // Stores number of bytes read   
  631.                                &port->m_ov);     // pointer to the m_ov structure   
  632.             // deal with the error code    
  633.             if (!bResult)    
  634.             {   
  635.                 switch (dwError = GetLastError())   
  636.                 {   
  637.                     case ERROR_IO_PENDING:    
  638.                         {   
  639.                             // asynchronous i/o is still in progress    
  640.                             // Proceed on to GetOverlappedResults();   
  641.                             bRead = FALSE;  
  642.                             break;  
  643.                         }  
  644.                     default:  
  645.                         {  
  646.                             // Another error has occured.  Process this error.   
  647.                             port->ProcessErrorMessage("ReadFile()");  
  648.                             break;  
  649.                         }   
  650.                 }  
  651.             }  
  652.             else  
  653.             {  
  654.                 // ReadFile() returned complete. It is not necessary to call GetOverlappedResults()   
  655.                 bRead = TRUE;  
  656.             }  
  657.         }  // close if (bRead)   
  658.   
  659.         if (!bRead)  
  660.         {  
  661.             bRead = TRUE;  
  662.             bResult = GetOverlappedResult(port->m_hComm, // Handle to COMM port    
  663.                                           &port->m_ov,       // Overlapped structure   
  664.                                           &BytesRead,       // Stores number of bytes read   
  665.                                           TRUE);            // Wait flag   
  666.   
  667.             // deal with the error code    
  668.             if (!bResult)    
  669.             {  
  670.                 port->ProcessErrorMessage("GetOverlappedResults() in ReadFile()");  
  671.             }     
  672.         }  // close if (!bRead)   
  673.                   
  674.         LeaveCriticalSection(&port->m_csCommunicationSync);  
  675.   
  676.         // notify parent that a byte was received   
  677.         ::SendMessage((port->m_pOwner)->m_hWnd, WM_COMM_RXCHAR, (WPARAM) RXBuff, (LPARAM) port->m_nPortNr);  
  678.     } // end forever loop   
  679.   
  680. }  
  681.   
  682. //   
  683. // Write a string to the port   
  684. //   
  685. void CSerialPort::WriteToPort(char* string)  
  686. {         
  687.     assert(m_hComm != 0);  
  688.   
  689.     memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));  
  690.     strcpy(m_szWriteBuffer, string);  
  691.     m_nWriteSize=strlen(string); // add by mrlong   
  692.     // set event for write   
  693.     SetEvent(m_hWriteEvent);  
  694. }  
  695.   
  696. //   
  697. // Return the device control block   
  698. //   
  699. DCB CSerialPort::GetDCB()  
  700. {  
  701.     return m_dcb;  
  702. }  
  703.   
  704. //   
  705. // Return the communication event masks   
  706. //   
  707. DWORD CSerialPort::GetCommEvents()  
  708. {  
  709.     return m_dwCommEvents;  
  710. }  
  711.   
  712. //   
  713. // Return the output buffer size   
  714. //   
  715. DWORD CSerialPort::GetWriteBufferSize()  
  716. {  
  717.     return m_nWriteBufferSize;  
  718. }  
  719.   
  720. void CSerialPort::ClosePort()  
  721. {  
/*
**	FILENAME			CSerialPort.cpp
**
**	PURPOSE				This class can read, write and watch one serial port.
**						It sends messages to its owner when something happends on the port
**						The class creates a thread for reading and writing so the main
**						program is not blocked.
**
**	CREATION DATE		15-09-1997
**	LAST MODIFICATION	12-11-1997
**
**	AUTHOR				Remon Spekreijse
**
**
*/

#include "stdafx.h"
#include "SerialPort.h"

#include <assert.h>
 
//
// Constructor
//
CSerialPort::CSerialPort()
{
	m_hComm = NULL;

	// initialize overlapped structure members to zero
	m_ov.Offset = 0;
	m_ov.OffsetHigh = 0;

	// create events
	m_ov.hEvent = NULL;
	m_hWriteEvent = NULL;
	m_hShutdownEvent = NULL;

	m_szWriteBuffer = NULL;

	m_bThreadAlive = FALSE;
	m_nWriteSize = 1;
}

//
// Delete dynamic memory
//
CSerialPort::~CSerialPort()
{
	do
	{
		SetEvent(m_hShutdownEvent);
	} while (m_bThreadAlive);

	if (m_hComm != NULL)
	{
		CloseHandle(m_hComm);
		m_hComm = NULL;
	}
	// Close Handles  
	if(m_hShutdownEvent!=NULL)
		CloseHandle( m_hShutdownEvent); 
	if(m_ov.hEvent!=NULL)
		CloseHandle( m_ov.hEvent ); 
	if(m_hWriteEvent!=NULL)
		CloseHandle( m_hWriteEvent ); 

	TRACE("Thread ended\n");

	delete [] m_szWriteBuffer;
}

//
// Initialize the port. This can be port 1 to 4.
//
//
//parity:
//  n=none
//  e=even
//  o=odd
//  m=mark
//  s=space
//data:
//  5,6,7,8
//stop:
//  1,1.5,2 
//
BOOL CSerialPort::InitPort(CWnd* pPortOwner,	// the owner (CWnd) of the port (receives message)
						   UINT  portnr,		// portnumber (1..4)
						   UINT  baud,			// baudrate
						   char  parity,		// parity 
						   UINT  databits,		// databits 
						   UINT  stopbits,		// stopbits 
						   DWORD dwCommEvents,	// EV_RXCHAR, EV_CTS etc
						   UINT  writebuffersize,// size to the writebuffer
						   
						   DWORD   ReadIntervalTimeout,
						   DWORD   ReadTotalTimeoutMultiplier,
						   DWORD   ReadTotalTimeoutConstant,
						   DWORD   WriteTotalTimeoutMultiplier,
						   DWORD   WriteTotalTimeoutConstant )	

{
	assert(portnr > 0 && portnr < 5);
	assert(pPortOwner != NULL);

	// if the thread is alive: Kill
	if (m_bThreadAlive)
	{
		do
		{
			SetEvent(m_hShutdownEvent);
		} while (m_bThreadAlive);
		TRACE("Thread ended\n");
	}

	// create events
	if (m_ov.hEvent != NULL)
		ResetEvent(m_ov.hEvent);
	else
		m_ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

	if (m_hWriteEvent != NULL)
		ResetEvent(m_hWriteEvent);
	else
		m_hWriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
	
	if (m_hShutdownEvent != NULL)
		ResetEvent(m_hShutdownEvent);
	else
		m_hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

	// initialize the event objects
	m_hEventArray[0] = m_hShutdownEvent;	// highest priority
	m_hEventArray[1] = m_ov.hEvent;
	m_hEventArray[2] = m_hWriteEvent;

	// initialize critical section
	InitializeCriticalSection(&m_csCommunicationSync);
	
	// set buffersize for writing and save the owner
	m_pOwner = pPortOwner;

	if (m_szWriteBuffer != NULL)
		delete [] m_szWriteBuffer;
	m_szWriteBuffer = new char[writebuffersize];

	m_nPortNr = portnr;

	m_nWriteBufferSize = writebuffersize;
	m_dwCommEvents = dwCommEvents;

	BOOL bResult = FALSE;
	char *szPort = new char[50];
	char *szBaud = new char[50];

	// now it critical!
	EnterCriticalSection(&m_csCommunicationSync);

	// if the port is already opened: close it
	if (m_hComm != NULL)
	{
		CloseHandle(m_hComm);
		m_hComm = NULL;
	}

	// prepare port strings
	sprintf(szPort, "COM%d", portnr);
	// stop is index 0 = 1 1=1.5 2=2
	int mystop;
	int myparity;
	switch(stopbits)
	{
		case 0:
			mystop = ONESTOPBIT;
			break;
		case 1:
			mystop = ONE5STOPBITS;
			break;
		case 2:
			mystop = TWOSTOPBITS;
			break;
	}
	myparity = 0;
	switch(parity)
	{
		case 'N':
			myparity = 0;
			break;
		case 'E':
			myparity = 1;
			break;
		case 'O':
			myparity = 2;
			break;
		case 'M':
			myparity = 3;
			break;
		case 'S':
			myparity = 4;
			break;
	}
	sprintf(szBaud, "baud=%d parity=%c data=%d stop=%d", baud, parity, databits, mystop);

	// get a handle to the port
	m_hComm = CreateFile(szPort,						// communication port string (COMX)
					     GENERIC_READ | GENERIC_WRITE,	// read/write types
					     0,								// comm devices must be opened with exclusive access
					     NULL,							// no security attributes
					     OPEN_EXISTING,					// comm devices must use OPEN_EXISTING
					     FILE_FLAG_OVERLAPPED,			// Async I/O
					     0);							// template must be 0 for comm devices

	if (m_hComm == INVALID_HANDLE_VALUE)
	{
		// port not found
		delete [] szPort;
		delete [] szBaud;

		return FALSE;
	}

	// set the timeout values
	m_CommTimeouts.ReadIntervalTimeout         = ReadIntervalTimeout * 1000;
	m_CommTimeouts.ReadTotalTimeoutMultiplier  = ReadTotalTimeoutMultiplier * 1000;
	m_CommTimeouts.ReadTotalTimeoutConstant    = ReadTotalTimeoutConstant * 1000;
	m_CommTimeouts.WriteTotalTimeoutMultiplier = WriteTotalTimeoutMultiplier * 1000;
	m_CommTimeouts.WriteTotalTimeoutConstant   = WriteTotalTimeoutConstant * 1000;

	// configure
	if (SetCommTimeouts(m_hComm, &m_CommTimeouts))
	{						   
		if (SetCommMask(m_hComm, dwCommEvents))
		{
			if (GetCommState(m_hComm, &m_dcb))
			{
				m_dcb.EvtChar = 'q';
				m_dcb.fRtsControl = RTS_CONTROL_ENABLE;		// set RTS bit high!
				m_dcb.BaudRate = baud;  // add by mrlong
				m_dcb.Parity   = myparity;
				m_dcb.ByteSize = databits;
				m_dcb.StopBits = mystop;
						
				//if (BuildCommDCB(szBaud, &m_dcb))
				//{
					if (SetCommState(m_hComm, &m_dcb))
						; // normal operation... continue
					else
						ProcessErrorMessage("SetCommState()");
				//}
				//else
				//	ProcessErrorMessage("BuildCommDCB()");
			}
			else
				ProcessErrorMessage("GetCommState()");
		}
		else
			ProcessErrorMessage("SetCommMask()");
	}
	else
		ProcessErrorMessage("SetCommTimeouts()");

	delete [] szPort;
	delete [] szBaud;

	// flush the port
	PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);

	// release critical section
	LeaveCriticalSection(&m_csCommunicationSync);

	TRACE("Initialisation for communicationport %d completed.\nUse Startmonitor to communicate.\n", portnr);

	return TRUE;
}

//
//  The CommThread Function.
//
UINT CSerialPort::CommThread(LPVOID pParam)
{
	// Cast the void pointer passed to the thread back to
	// a pointer of CSerialPort class
	CSerialPort *port = (CSerialPort*)pParam;
	
	// Set the status variable in the dialog class to
	// TRUE to indicate the thread is running.
	port->m_bThreadAlive = TRUE;	
		
	// Misc. variables
	DWORD BytesTransfered = 0; 
	DWORD Event = 0;
	DWORD CommEvent = 0;
	DWORD dwError = 0;
	COMSTAT comstat;
	BOOL  bResult = TRUE;
		
	// Clear comm buffers at startup
	if (port->m_hComm)		// check if the port is opened
		PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);

	// begin forever loop.  This loop will run as long as the thread is alive.
	for (;;) 
	{ 

		// Make a call to WaitCommEvent().  This call will return immediatly
		// because our port was created as an async port (FILE_FLAG_OVERLAPPED
		// and an m_OverlappedStructerlapped structure specified).  This call will cause the 
		// m_OverlappedStructerlapped element m_OverlappedStruct.hEvent, which is part of the m_hEventArray to 
		// be placed in a non-signeled state if there are no bytes available to be read,
		// or to a signeled state if there are bytes available.  If this event handle 
		// is set to the non-signeled state, it will be set to signeled when a 
		// character arrives at the port.

		// we do this for each port!

		bResult = WaitCommEvent(port->m_hComm, &Event, &port->m_ov);

		if (!bResult)  
		{ 
			// If WaitCommEvent() returns FALSE, process the last error to determin
			// the reason..
			switch (dwError = GetLastError()) 
			{ 
			case ERROR_IO_PENDING: 	
				{ 
					// This is a normal return value if there are no bytes
					// to read at the port.
					// Do nothing and continue
					break;
				}
			case 87:
				{
					// Under Windows NT, this value is returned for some reason.
					// I have not investigated why, but it is also a valid reply
					// Also do nothing and continue.
					break;
				}
			default:
				{
					// All other error codes indicate a serious error has
					// occured.  Process this error.
					port->ProcessErrorMessage("WaitCommEvent()");
					break;
				}
			}
		}
		else
		{
			// If WaitCommEvent() returns TRUE, check to be sure there are
			// actually bytes in the buffer to read.  
			//
			// If you are reading more than one byte at a time from the buffer 
			// (which this program does not do) you will have the situation occur 
			// where the first byte to arrive will cause the WaitForMultipleObjects() 
			// function to stop waiting.  The WaitForMultipleObjects() function 
			// resets the event handle in m_OverlappedStruct.hEvent to the non-signelead state
			// as it returns.  
			//
			// If in the time between the reset of this event and the call to 
			// ReadFile() more bytes arrive, the m_OverlappedStruct.hEvent handle will be set again
			// to the signeled state. When the call to ReadFile() occurs, it will 
			// read all of the bytes from the buffer, and the program will
			// loop back around to WaitCommEvent().
			// 
			// At this point you will be in the situation where m_OverlappedStruct.hEvent is set,
			// but there are no bytes available to read.  If you proceed and call
			// ReadFile(), it will return immediatly due to the async port setup, but
			// GetOverlappedResults() will not return until the next character arrives.
			//
			// It is not desirable for the GetOverlappedResults() function to be in 
			// this state.  The thread shutdown event (event 0) and the WriteFile()
			// event (Event2) will not work if the thread is blocked by GetOverlappedResults().
			//
			// The solution to this is to check the buffer with a call to ClearCommError().
			// This call will reset the event handle, and if there are no bytes to read
			// we can loop back through WaitCommEvent() again, then proceed.
			// If there are really bytes to read, do nothing and proceed.
		
			bResult = ClearCommError(port->m_hComm, &dwError, &comstat);

			if (comstat.cbInQue == 0)
				continue;
		}	// end if bResult

		// Main wait function.  This function will normally block the thread
		// until one of nine events occur that require action.
		Event = WaitForMultipleObjects(3, port->m_hEventArray, FALSE, INFINITE);

		switch (Event)
		{
		case 0:
			{
				// Shutdown event.  This is event zero so it will be
				// the higest priority and be serviced first.

			 	port->m_bThreadAlive = FALSE;
				
				// Kill this thread.  break is not needed, but makes me feel better.
				AfxEndThread(100);
				break;
			}
		case 1:	// read event
			{
				GetCommMask(port->m_hComm, &CommEvent);
				if (CommEvent & EV_RXCHAR) //接收到字符，并置于输入缓冲区中 
					ReceiveChar(port, comstat);
				
				if (CommEvent & EV_CTS) //CTS信号状态发生变化
					::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_CTS_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
				if (CommEvent & EV_RXFLAG) //接收到事件字符，并置于输入缓冲区中 
					::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RXFLAG_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
				if (CommEvent & EV_BREAK)  //输入中发生中断
					::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_BREAK_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
				if (CommEvent & EV_ERR) //发生线路状态错误，线路状态错误包括CE_FRAME,CE_OVERRUN和CE_RXPARITY 
					::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_ERR_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
				if (CommEvent & EV_RING) //检测到振铃指示
					::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RING_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
					
				break;
			}  
		case 2: // write event
			{
				// Write character event from port
				WriteChar(port);
				break;
			}

		} // end switch

	} // close forever loop

	return 0;
}

//
// start comm watching
//
BOOL CSerialPort::StartMonitoring()
{
	if (!(m_Thread = AfxBeginThread(CommThread, this)))
		return FALSE;
	TRACE("Thread started\n");
	return TRUE;	
}

//
// Restart the comm thread
//
BOOL CSerialPort::RestartMonitoring()
{
	TRACE("Thread resumed\n");
	m_Thread->ResumeThread();
	return TRUE;	
}


//
// Suspend the comm thread
//
BOOL CSerialPort::StopMonitoring()
{
	TRACE("Thread suspended\n");
	m_Thread->SuspendThread(); 
	return TRUE;	
}


//
// If there is a error, give the right message
//
void CSerialPort::ProcessErrorMessage(char* ErrorText)
{
	char *Temp = new char[200];
	
	LPVOID lpMsgBuf;

	FormatMessage( 
		FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
		NULL,
		GetLastError(),
		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
		(LPTSTR) &lpMsgBuf,
		0,
		NULL 
	);

	sprintf(Temp, "WARNING:  %s Failed with the following error: \n%s\nPort: %d\n", (char*)ErrorText, lpMsgBuf, m_nPortNr); 
	MessageBox(NULL, Temp, "Application Error", MB_ICONSTOP);

	LocalFree(lpMsgBuf);
	delete[] Temp;
}

//
// Write a character.
//
void CSerialPort::WriteChar(CSerialPort* port)
{
	BOOL bWrite = TRUE;
	BOOL bResult = TRUE;

	DWORD BytesSent = 0;
	DWORD SendLen   = port->m_nWriteSize;
	ResetEvent(port->m_hWriteEvent);


	// Gain ownership of the critical section
	EnterCriticalSection(&port->m_csCommunicationSync);

	if (bWrite)
	{
		// Initailize variables
		port->m_ov.Offset = 0;
		port->m_ov.OffsetHigh = 0;
     
		// Clear buffer
		PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);

		bResult = WriteFile(port->m_hComm,							// Handle to COMM Port
							port->m_szWriteBuffer,					// Pointer to message buffer in calling finction
							SendLen,    // add by mrlong
							//strlen((char*)port->m_szWriteBuffer),	// Length of message to send
							&BytesSent,								// Where to store the number of bytes sent
							&port->m_ov);							// Overlapped structure

		// deal with any error codes
		if (!bResult)  
		{
			DWORD dwError = GetLastError();
			switch (dwError)
			{
				case ERROR_IO_PENDING:
					{
						// continue to GetOverlappedResults()
						BytesSent = 0;
						bWrite = FALSE;
						break;
					}
				default:
					{
						// all other error codes
						port->ProcessErrorMessage("WriteFile()");
					}
			}
		} 
		else
		{
			LeaveCriticalSection(&port->m_csCommunicationSync);
		}
	} // end if(bWrite)

	if (!bWrite)
	{
		bWrite = TRUE;
	
		bResult = GetOverlappedResult(port->m_hComm,	// Handle to COMM port 
									  &port->m_ov,		// Overlapped structure
									  &BytesSent,		// Stores number of bytes sent
									  TRUE); 			// Wait flag

		LeaveCriticalSection(&port->m_csCommunicationSync);

		// deal with the error code 
		if (!bResult)  
		{
			port->ProcessErrorMessage("GetOverlappedResults() in WriteFile()");
		}	
	} // end if (!bWrite)

	// Verify that the data size send equals what we tried to send
	if (BytesSent != SendLen /*strlen((char*)port->m_szWriteBuffer)*/)  // add by 
	{
		TRACE("WARNING: WriteFile() error.. Bytes Sent: %d; Message Length: %d\n", BytesSent, strlen((char*)port->m_szWriteBuffer));
	}
}

//
// Character received. Inform the owner
//
void CSerialPort::ReceiveChar(CSerialPort* port, COMSTAT comstat)
{
	BOOL  bRead = TRUE; 
	BOOL  bResult = TRUE;
	DWORD dwError = 0;
	DWORD BytesRead = 0;
	unsigned char RXBuff;

	for (;;) 
	{ 
             //add by liquanhai 2011-11-06  防止死锁
             if(WaitForSingleObject(port->m_hShutdownEvent,0)==WAIT_OBJECT_0)
                 return;

                // Gain ownership of the comm port critical section.
		// This process guarantees no other part of this program 
		// is using the port object. 
		
		EnterCriticalSection(&port->m_csCommunicationSync);

		// ClearCommError() will update the COMSTAT structure and
		// clear any other errors.
		
		bResult = ClearCommError(port->m_hComm, &dwError, &comstat);

		LeaveCriticalSection(&port->m_csCommunicationSync);

		// start forever loop.  I use this type of loop because I
		// do not know at runtime how many loops this will have to
		// run. My solution is to start a forever loop and to
		// break out of it when I have processed all of the
		// data available.  Be careful with this approach and
		// be sure your loop will exit.
		// My reasons for this are not as clear in this sample 
		// as it is in my production code, but I have found this 
		// solutiion to be the most efficient way to do this.
		
		if (comstat.cbInQue == 0)
		{
			// break out when all bytes have been read
			break;
		}
						
		EnterCriticalSection(&port->m_csCommunicationSync);

		if (bRead)
		{
			bResult = ReadFile(port->m_hComm,		// Handle to COMM port 
							   &RXBuff,				// RX Buffer Pointer
							   1,					// Read one byte
							   &BytesRead,			// Stores number of bytes read
							   &port->m_ov);		// pointer to the m_ov structure
			// deal with the error code 
			if (!bResult)  
			{ 
				switch (dwError = GetLastError()) 
				{ 
					case ERROR_IO_PENDING: 	
						{ 
							// asynchronous i/o is still in progress 
							// Proceed on to GetOverlappedResults();
							bRead = FALSE;
							break;
						}
					default:
						{
							// Another error has occured.  Process this error.
							port->ProcessErrorMessage("ReadFile()");
							break;
						} 
				}
			}
			else
			{
				// ReadFile() returned complete. It is not necessary to call GetOverlappedResults()
				bRead = TRUE;
			}
		}  // close if (bRead)

		if (!bRead)
		{
			bRead = TRUE;
			bResult = GetOverlappedResult(port->m_hComm,	// Handle to COMM port 
										  &port->m_ov,		// Overlapped structure
										  &BytesRead,		// Stores number of bytes read
										  TRUE); 			// Wait flag

			// deal with the error code 
			if (!bResult)  
			{
				port->ProcessErrorMessage("GetOverlappedResults() in ReadFile()");
			}	
		}  // close if (!bRead)
				
		LeaveCriticalSection(&port->m_csCommunicationSync);

		// notify parent that a byte was received
		::SendMessage((port->m_pOwner)->m_hWnd, WM_COMM_RXCHAR, (WPARAM) RXBuff, (LPARAM) port->m_nPortNr);
	} // end forever loop

}

//
// Write a string to the port
//
void CSerialPort::WriteToPort(char* string)
{		
	assert(m_hComm != 0);

	memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
	strcpy(m_szWriteBuffer, string);
	m_nWriteSize=strlen(string); // add by mrlong
	// set event for write
	SetEvent(m_hWriteEvent);
}

//
// Return the device control block
//
DCB CSerialPort::GetDCB()
{
	return m_dcb;
}

//
// Return the communication event masks
//
DWORD CSerialPort::GetCommEvents()
{
	return m_dwCommEvents;
}

//
// Return the output buffer size
//
DWORD CSerialPort::GetWriteBufferSize()
{
	return m_nWriteBufferSize;
}

void CSerialPort::ClosePort()
{
[cpp] view plaincopyprint?在CODE上查看代码片派生到我的代码片
  1.         MSG message;  
  2.     do  
  3.     {  
  4.           SetEvent(m_hShutdownEvent);  
  5.               if(::PeekMessage(&message,m_pOwner->m_hWnd,0,0,PM_REMOVE))  
  6.                {  
  7.                ::TranslateMessage(&message);  
  8.                 ::DispatchMessage(&message);  
  9.               }  
  10.                  
  11.          } while (m_bThreadAlive);  
  12.   
  13.     // if the port is still opened: close it    
  14.     if (m_hComm != NULL)  
  15.     {  
  16.         CloseHandle(m_hComm);  
  17.         m_hComm = NULL;  
  18.     }  
  19.       
  20.     // Close Handles     
  21.     if(m_hShutdownEvent!=NULL)  
  22.         ResetEvent(m_hShutdownEvent);  
  23.     if(m_ov.hEvent!=NULL)  
  24.         ResetEvent(m_ov.hEvent);  
  25.     if(m_hWriteEvent!=NULL)  
  26.         ResetEvent(m_hWriteEvent);            
  27.           
  28.     //delete [] m_szWriteBuffer;   
  29.       
  30. }  
  31.   
  32. void CSerialPort::WriteToPort(char* string,int n)  
  33. {  
  34.     assert(m_hComm != 0);  
  35.     memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));  
  36.     memcpy(m_szWriteBuffer, string, n);  
  37.     m_nWriteSize = n;  
  38.   
  39.     // set event for write   
  40.     SetEvent(m_hWriteEvent);  
  41. }  
  42.   
  43. void CSerialPort::WriteToPort(LPCTSTR string)  
  44. {  
  45.     assert(m_hComm != 0);  
  46.     memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));  
  47.     strcpy(m_szWriteBuffer, string);  
  48.     m_nWriteSize=strlen(string);  
  49.     // set event for write   
  50.     SetEvent(m_hWriteEvent);  
  51. }  
  52.   
  53. void CSerialPort::WriteToPort(BYTE* Buffer, int n)  
  54. {  
  55.     assert(m_hComm != 0);  
  56.     memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));  
  57.     int i;  
  58.     for(i=0; i<n; i++)  
  59.     {  
  60.         m_szWriteBuffer[i] = Buffer[i];  
  61.     }  
  62.     m_nWriteSize=n;  
  63.   
  64.     // set event for write   
  65.     SetEvent(m_hWriteEvent);  
  66. }  
  67.   
  68.   
  69. void CSerialPort::SendData(LPCTSTR lpszData, const int nLength)  
  70. {  
  71.     assert(m_hComm != 0);  
  72.     memset(m_szWriteBuffer, 0, nLength);  
  73.     strcpy(m_szWriteBuffer, lpszData);  
  74.     m_nWriteSize=nLength;  
  75.     // set event for write   
  76.     SetEvent(m_hWriteEvent);  
  77. }  
  78.   
  79. BOOL CSerialPort::RecvData(LPTSTR lpszData, const int nSize)  
  80. {  
  81.     //   
  82.     //接收数据   
  83.     //   
  84.     assert(m_hComm!=0);  
  85.     memset(lpszData,0,nSize);  
  86.     DWORD mylen  = 0;  
  87.     DWORD mylen2 = 0;  
  88.     while (mylen<nSize) {  
  89.         if(!ReadFile(m_hComm,lpszData,nSize,&mylen2,NULL))   
  90.             return FALSE;  
  91.         mylen += mylen2;  
  92.   
  93.           
  94.     }  
  95.       
  96.     return TRUE;  
  97. }  
        MSG message;
	do
	{
	      SetEvent(m_hShutdownEvent);
              if(::PeekMessage(&message,m_pOwner->m_hWnd,0,0,PM_REMOVE))
               {
               ::TranslateMessage(&message);
                ::DispatchMessage(&message);
              }
               
         } while (m_bThreadAlive);

	// if the port is still opened: close it 
	if (m_hComm != NULL)
	{
		CloseHandle(m_hComm);
		m_hComm = NULL;
	}
	
	// Close Handles  
	if(m_hShutdownEvent!=NULL)
		ResetEvent(m_hShutdownEvent);
	if(m_ov.hEvent!=NULL)
		ResetEvent(m_ov.hEvent);
	if(m_hWriteEvent!=NULL)
		ResetEvent(m_hWriteEvent);			
		
	//delete [] m_szWriteBuffer;
	
}

void CSerialPort::WriteToPort(char* string,int n)
{
	assert(m_hComm != 0);
	memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
	memcpy(m_szWriteBuffer, string, n);
	m_nWriteSize = n;

	// set event for write
	SetEvent(m_hWriteEvent);
}

void CSerialPort::WriteToPort(LPCTSTR string)
{
	assert(m_hComm != 0);
	memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
	strcpy(m_szWriteBuffer, string);
	m_nWriteSize=strlen(string);
	// set event for write
	SetEvent(m_hWriteEvent);
}

void CSerialPort::WriteToPort(BYTE* Buffer, int n)
{
	assert(m_hComm != 0);
	memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
	int i;
	for(i=0; i<n; i++)
	{
		m_szWriteBuffer[i] = Buffer[i];
	}
	m_nWriteSize=n;

	// set event for write
	SetEvent(m_hWriteEvent);
}


void CSerialPort::SendData(LPCTSTR lpszData, const int nLength)
{
	assert(m_hComm != 0);
	memset(m_szWriteBuffer, 0, nLength);
	strcpy(m_szWriteBuffer, lpszData);
	m_nWriteSize=nLength;
	// set event for write
	SetEvent(m_hWriteEvent);
}

BOOL CSerialPort::RecvData(LPTSTR lpszData, const int nSize)
{
	//
	//接收数据
	//
	assert(m_hComm!=0);
	memset(lpszData,0,nSize);
	DWORD mylen  = 0;
	DWORD mylen2 = 0;
	while (mylen<nSize) {
		if(!ReadFile(m_hComm,lpszData,nSize,&mylen2,NULL)) 
			return FALSE;
		mylen += mylen2;

		
	}
	
	return TRUE;
}

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posted on 2014-04-07 15:39  bitbit  阅读(2866)  评论(0)    收藏  举报

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