Knowledge Base Nr: 00232 socketsupport.cpp - http://www.swe-kaiser.de

MFC: Erweiterungen der MFC-Sockets

  
#ifndef SOCKETSUPPORT_H
#define SOCKETSUPPORT_H

#define MAXLEN 4096

#include <afxsock.h>

class CSocketSupport : public CAsyncSocket
{
public:
    CSocketSupport(bool bLineMode = true);
    virtual ~CSocketSupport();

    void SetLineMode(bool bLineMode) { m_bLineMode = bLineMode; }

    virtual void OnError(const char* lpszError);
   virtual void OnSocketReceive(const char* lpszData, int nDataLen);

    virtual void OnConnect(int nErrorCode);
    bool IsConnected() { return m_bInitialized; }

protected:
    bool m_bLineMode;
    bool m_bInitialized;

    char m_cBuffer[MAXLEN];
    int m_nCurr;

    virtual void OnReceive(int nErrorCode);
    virtual void OnClose(int nErrorCode);
};

#endif // SOCKETSUPPORT_H

//////////////////////////////////////////////////////////////////////

#include <afxwin.h>         // MFC core and standard components
#include <afxsock.h>        // MFC socket extensions
#include "SocketSupport.h"

CSocketSupport::CSocketSupport(bool bLineMode)
{
    m_bLineMode = bLineMode;
    m_bInitialized = false;
    m_nCurr = 0;
    ZeroMemory(m_cBuffer, sizeof(m_cBuffer));
}

CSocketSupport::~CSocketSupport()
{
}

void CSocketSupport::OnError(const char* lpszError)
{
    MessageBox(NULL, lpszError, "SocketClient", MB_OK);
}

void CSocketSupport::OnSocketReceive(const char* lpszData, int nDataLen)
{
    MessageBox(NULL, lpszData, "SocketClient", MB_OK);
}

void CSocketSupport::OnConnect(int nErrorCode)
{
    CAsyncSocket::OnConnect(nErrorCode);

    if (nErrorCode!=0)
    {
        m_bInitialized = false;
        OnError("Failed to connect to server.");
        Close();
    }
    else
    {
        m_bInitialized = true;
    }
}

void CSocketSupport::OnReceive(int nErrorCode)
{
    CAsyncSocket::OnReceive(nErrorCode);

    if (nErrorCode != 0)
    {
        m_bInitialized = false;
        OnError("Network connection failed.");
        Close();
    }
    else
    {
        char szTmp[MAXLEN+1] = {0};

        int nLen = Receive(szTmp, sizeof(szTmp));
        if ((nLen == SOCKET_ERROR) || (nLen == 0))
            return;

        if (!m_bLineMode)
        {
            // send it to the app
            OnSocketReceive(szTmp, nLen);
        }
        else
        {
            if (m_nCurr + nLen >= MAXLEN) // too much data, lose it
                m_nCurr=0;

            for (int i=0; i<nLen; i++)
                m_cBuffer[m_nCurr++] = szTmp[i];

          // find a newline
            while (1)
            {
                for (i=0; i<m_nCurr; i++)
                {
                    if ((m_cBuffer[i] == '\n') || (m_cBuffer[i] == '\r'))
                    {
                        //m_cBuffer[i] = 0;
                        i--;
                        break;
                    }
                }

                if (i == m_nCurr) // no newline
                    return;

                // found a newline: copy that much of m_cBuffer into szTmp
                int nPosNewLine = i;
                for (i=0; i<=nPosNewLine; i++)
                    szTmp[i] = m_cBuffer[i];
                szTmp[i] = 0; // null terminate it
                nLen = strlen(szTmp);

                // send it to the app
                if (nLen)
                    OnSocketReceive(szTmp, nLen);

                int n=0;
                for (i=nPosNewLine+1; i<=m_nCurr; i++)
                {
                    m_cBuffer[n] = m_cBuffer[i];
                    n++;
                   m_nCurr--;
                }
            }
        }
    }
}

void CSocketSupport::OnClose(int nErrorCode)
{
    CAsyncSocket::OnClose(nErrorCode);

    if (m_bInitialized && nErrorCode!=0)
        OnError("Connection to SocketClient server lost.");

    m_bInitialized = false;
}