串口通信

这里采用字符串池实现串口数据接收，串口类改自一个老外写的CSerialPort类。

/*
**  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
**
**
*/
#include "stringpool.h"

#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(CWinThread* 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);

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

    DWORD       GetWriteBufferSize();
    DWORD       GetCommEvents();
    DCB         GetDCB();
    std::string *GetFrontString();

    void        WriteToPort(char* string);

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;
    CRITICAL_SECTION m_csQueLock;       //队列锁
    BOOL                m_bThreadAlive;

    //事件对象
    HANDLE              m_hShutdownEvent;
    HANDLE              m_hComm;
    HANDLE              m_hWriteEvent;
    HANDLE              m_hEventArray[3];

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

public:
    CWinThread*             m_pOwner;
    StringPool *m_pStringPool;
    // misc
    UINT                m_nPortNr;
    char*               m_szWriteBuffer;
    DWORD               m_dwCommEvents;
    DWORD               m_nWriteBufferSize;
    UINT                m_nDataLen;
    queue<string *> m_strQue;         //字符串接收队列
};

#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
**
**
*/
#include "stringpool.h"

#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(CWinThread* 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);

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

	DWORD		GetWriteBufferSize();
	DWORD		GetCommEvents();
	DCB			GetDCB();
	std::string *GetFrontString();

	void		WriteToPort(char* string);

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;
	CRITICAL_SECTION m_csQueLock;		//队列锁
	BOOL				m_bThreadAlive;

	//事件对象
	HANDLE				m_hShutdownEvent;
	HANDLE				m_hComm;
	HANDLE				m_hWriteEvent;
	HANDLE				m_hEventArray[3];
	
	// structures
	OVERLAPPED			m_ov;
	COMMTIMEOUTS		m_CommTimeouts;
	DCB					m_dcb;

public:
	CWinThread*				m_pOwner;
	StringPool *m_pStringPool;
	// misc
	UINT				m_nPortNr;
	char*				m_szWriteBuffer;
	DWORD				m_dwCommEvents;
	DWORD				m_nWriteBufferSize;
	UINT				m_nDataLen;
	queue<string *> m_strQue;			//字符串接收队列
};

#endif __SERIALPORT_H__

/*
**  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;
}

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

    TRACE("Thread ended\n");

    delete [] m_szWriteBuffer;
}

//
// Initialize the port. This can be port 1 to 4.
//
BOOL CSerialPort::InitPort(CWinThread* pPortOwner,  // the owner (CWinTread) of the port (receives message)
                           UINT  portnr,        //端口号
                           UINT  baud,          //波特率
                           char  parity,        //奇偶校验位
                           UINT  databits,      //数据位
                           UINT  stopbits,      // 停止位
                           DWORD dwCommEvents,  // 准备监视的串口事件掩码
                           UINT  writebuffersize)   // 写缓冲区大小
{
    assert(portnr > 0 && portnr < 5);
    assert(pPortOwner != NULL);

    //判断线程是否启动，否则结束线程
    if (m_bThreadAlive)
    {
        do
        {
            SetEvent(m_hShutdownEvent);
        } while (m_bThreadAlive);
        TRACE("Thread ended\n");
    }

    //重叠事件对象
    if (m_ov.hEvent != NULL)
        ResetEvent(m_ov.hEvent);
    m_ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

    //写事件对象
    if (m_hWriteEvent != NULL)
        ResetEvent(m_hWriteEvent);
    m_hWriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

    //线程退出事件对象，有信号则线程退出
    if (m_hShutdownEvent != NULL)
        ResetEvent(m_hShutdownEvent);
    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;

    InitializeCriticalSection(&m_csCommunicationSync);
    InitializeCriticalSection(&m_csQueLock);

    // set buffersize for writing and save the owner
    m_pOwner = pPortOwner;
    m_pStringPool = new StringPool;

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

    m_nPortNr = portnr;

    m_nWriteBufferSize = writebuffersize;
    m_dwCommEvents = dwCommEvents;
    m_nDataLen = 15;

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

    //锁住串口，防止对同一串口进行操作
    EnterCriticalSection(&m_csCommunicationSync);

    if (m_hComm != NULL)
    {
        CloseHandle(m_hComm);
        m_hComm = NULL;
    }

    //串口连接字符串
    sprintf(szPort, "COM%d", portnr);
    sprintf(szBaud, "baud=%d parity=%c data=%d stop=%d", baud, parity, databits, stopbits);

    //打开串口
    m_hComm = CreateFileA(szPort,                       //串口号
                         GENERIC_READ | GENERIC_WRITE,  // 允许读写
                         0,                             // 以独占模式打开
                         NULL,                          // 无安全属性
                         OPEN_EXISTING,                 // 通讯设备已存在
                         FILE_FLAG_OVERLAPPED,          // 异步IO
                         0);                            //通讯设备不能用模板打开

    if (m_hComm == INVALID_HANDLE_VALUE)
    {
        // 串口未找到
        delete [] szPort;
        delete [] szBaud;

        return FALSE;
    }

    // 设置超时值
    m_CommTimeouts.ReadIntervalTimeout = 1000;
    m_CommTimeouts.ReadTotalTimeoutMultiplier = 1000;
    m_CommTimeouts.ReadTotalTimeoutConstant = 1000;
    m_CommTimeouts.WriteTotalTimeoutMultiplier = 1000;
    m_CommTimeouts.WriteTotalTimeoutConstant = 1000;

    if (SetCommTimeouts(m_hComm, &m_CommTimeouts))
    {
        //设置串口要监视的事件
        if (SetCommMask(m_hComm, dwCommEvents))
        {
            //读取串口配置
            if (GetCommState(m_hComm, &m_dcb))
            {
                m_dcb.fRtsControl = RTS_CONTROL_ENABLE;     // set RTS bit high!
                //连接串口
                if (BuildCommDCBA(szBaud, &m_dcb))
                {
                    //修改串口配置
                    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;

    // 清空缓冲区
    PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);

    LeaveCriticalSection(&m_csCommunicationSync);

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

    return TRUE;
}

UINT CSerialPort::CommThread(LPVOID pParam)
{
    CSerialPort *port = (CSerialPort*)pParam;

    //串口线程运行标志
    port->m_bThreadAlive = TRUE;

    DWORD BytesTransfered = 0;
    DWORD Event = 0;
    DWORD CommEvent = 0;
    DWORD dwError = 0;
    COMSTAT comstat;
    BOOL  bResult = TRUE;

    //检查串口是否打开
    if (port->m_hComm)
        PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);

    //初始化COMSTAT
    ClearCommError(port->m_hComm, &dwError, &comstat);
    for (;;)
    {
        //等待串口事件发生，异步操作直接返回
        bResult = WaitCommEvent(port->m_hComm, &Event, &port->m_ov);

        if (!bResult)
        {
            //错误处理
            switch (dwError = GetLastError())
            {
            case ERROR_IO_PENDING:
                {
                    break;
                }
            case 87:
                {
                    //特殊处理
                    break;
                }
            default:
                {
                    port->ProcessErrorMessage("WaitCommEvent()");
                    break;
                }
            }
        }
        //正常处理
        else
        {
            //清除串口的通信错误，返回当前的错误状态
            bResult = ClearCommError(port->m_hComm, &dwError, &comstat);

            //串口未发送数据
            if (comstat.cbInQue == 0)
                continue;
        }

        //等待串口事件发生
        Event = WaitForMultipleObjects(3, port->m_hEventArray, FALSE, INFINITE);

        switch (Event)
        {
        case 0:
            {
                //0号事件对象拥有高优先权，会优先到达
                port->m_bThreadAlive = FALSE;

                //线程直接退出
                AfxEndThread(100);
                break;
            }
        case 1: // 读事件
            {
                //读取串口事件掩码
                GetCommMask(port->m_hComm, &CommEvent);

                if (CommEvent & EV_CTS)//CTS信号状态发生变化
                    ::PostThreadMessage(port->m_pOwner->m_nThreadID, 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
                    ::PostThreadMessage(port->m_pOwner->m_nThreadID, WM_COMM_RXFLAG_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
                if (CommEvent & EV_BREAK) //输入中发生中断
                    ::PostThreadMessage(port->m_pOwner->m_nThreadID, 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
                    ::PostThreadMessage(port->m_pOwner->m_nThreadID, WM_COMM_ERR_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
                if (CommEvent & EV_RING)//检测到振铃指示
                    ::PostThreadMessage(port->m_pOwner->m_nThreadID, WM_COMM_RING_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);

                if (CommEvent & EV_RXCHAR)
                    //接收到字符，并置于输入缓冲区中
                    ReceiveChar(port, comstat);

                break;
            }
        case 2: // 写事件
            {
                WriteChar(port);
                break;
            }
        }
    }

    return 0;
}

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

//唤醒线程
BOOL CSerialPort::RestartMonitoring()
{
    TRACE("Thread resumed\n");
    m_Thread->ResumeThread();
    return TRUE;
}


//线程挂起
BOOL CSerialPort::StopMonitoring()
{
    TRACE("Thread suspended\n");
    m_Thread->SuspendThread();
    return TRUE;
}


//查找详细错误信息
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);
    MessageBoxA(NULL, Temp, "Application Error", MB_ICONSTOP);

    LocalFree(lpMsgBuf);
    delete[] Temp;
}

void CSerialPort::WriteChar(CSerialPort* port)
{
    BOOL bWrite = TRUE;
    BOOL bResult = TRUE;

    DWORD BytesSent = 0;

    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,
                            port->m_szWriteBuffer,                   // 发送缓冲区首地址
                            strlen((char*)port->m_szWriteBuffer),    // 消息发送长度
                            &BytesSent,                             // 实际写入字节数的存储区域指针
                            &port->m_ov);

        // 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,       // 发送字节数
                                      TRUE);            // 等待标志

        LeaveCriticalSection(&port->m_csCommunicationSync);

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

    //验证是否是期望发送长度
    if (BytesSent != strlen((char*)port->m_szWriteBuffer))
    {
        TRACE("WARNING: WriteFile() error.. Bytes Sent: %d; Message Length: %d\n", BytesSent, strlen((char*)port->m_szWriteBuffer));
    }
}

void CSerialPort::ReceiveChar(CSerialPort* port, COMSTAT comstat)
{
    BOOL  bRead = TRUE;
    BOOL  bResult = TRUE;
    DWORD dwError = 0;
    DWORD BytesRead = 0;
    unsigned char RXBuff[1024];
    int nRecvChar = 1;

    memset(RXBuff, 0, 1024);
    for (;;)
    {
        //获得串口权限
        EnterCriticalSection(&port->m_csCommunicationSync);

        ////清除串口的通信错误返回当前串口状态
        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)
        {
            //接收缓冲区为空直接退出
            break;
        }

        EnterCriticalSection(&port->m_csCommunicationSync);

        //读缓冲区
        if (bRead)
        {
            bResult = ReadFile(port->m_hComm,        // 串口句柄
                               &RXBuff,                         // 读缓冲区地址
                               nRecvChar,                       // 要读取的长度
                               &BytesRead,                      // 读取长度
                               &port->m_ov);

            //正常返回值为FALSE，调用GetOverlappedResult获取重叠结果
            if (!bResult)
            {
                switch (dwError = GetLastError())
                {
                    case ERROR_IO_PENDING:
                        {
                            bRead = FALSE;
                            break;
                        }
                    default:
                        {
                            port->ProcessErrorMessage("ReadFile()");
                            break;
                        }
                }
            }
            else
            {
                //读取操作完成，不需要调用GetOverlappedResult
                bRead = TRUE;
            }
        }
        //获取异步结果
        if (!bRead)
        {
            //重置bRead
            bRead = TRUE;
            bResult = GetOverlappedResult(port->m_hComm,
                                          &port->m_ov,
                                          &BytesRead,   //返回读取的长度
                                          TRUE);            // 等待标志
            if (!bResult)
            {
                port->ProcessErrorMessage("GetOverlappedResults() in ReadFile()");
            }
        }

        if (bRead)
        {
            if (RXBuff[0] == '#')
            {
                nRecvChar = port->m_nDataLen;
                continue;
            }
            if (strlen((char*)&RXBuff[0]) < port->m_nDataLen)
            {
                nRecvChar = 1;
                continue;
            }
            std::string *pStrMsg = (port->m_pStringPool)->GetAString();
            pStrMsg->assign((char *)&RXBuff[0], BytesRead);
            if (pStrMsg->find('#') != std::string::npos)
            {
                nRecvChar = 1;
                (port->m_pStringPool)->ReleaseAString(pStrMsg);
                continue;
            }
            nRecvChar = 1;
            //将字符串放入接收队列
            EnterCriticalSection(&port->m_csQueLock);
            port->m_strQue.push(pStrMsg);
            LeaveCriticalSection(&port->m_csQueLock);
        }

        LeaveCriticalSection(&port->m_csCommunicationSync);

        ::PostThreadMessage((port->m_pOwner)->m_nThreadID, WM_COMM_RXCHAR, (WPARAM) port, (LPARAM) port->m_nPortNr);
    }

}

void CSerialPort::WriteToPort(char* string)
{
    assert(m_hComm != 0);

    memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
    strcpy(m_szWriteBuffer, string);

    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;
}

std::string *CSerialPort::GetFrontString()
{
    EnterCriticalSection(&m_csQueLock);
    if (!m_strQue.empty())
    {
        string *pString = m_strQue.front();
        m_strQue.pop();
        LeaveCriticalSection(&m_csQueLock);
        return pString;
    }
    else
    {
        LeaveCriticalSection(&m_csQueLock);
        return NULL;
    }
}