multithreadingserver.c

labwindow 编程的tcp网络开发例程。

/*---------------------------------------------------------------------------*/
/*                                                                           */
/* FILE:    MultiThreadingServer.c                                           */
/*                                                                           */
/* PURPOSE: This program creates a simple TCP server to be used with the     */
/*          MultiThreadingClient sample program.                             */
/*                                                                           */
/*---------------------------------------------------------------------------*/

/*---------------------------------------------------------------------------*/
/* Include files                                                             */
/*---------------------------------------------------------------------------*/
#include <ansi_c.h>
#include <tcpsupp.h>
#include <cvirte.h>     
#include <userint.h>
#include "MultiThreadingServer.h"

/*---------------------------------------------------------------------------*/
/* Macros                                                                    */
/*---------------------------------------------------------------------------*/
#define tcpChk(f) if ((gTCPError=(f)) < 0) {ReportTCPError(); goto Done;} else

/*---------------------------------------------------------------------------*/
/* Module-globals                                                            */
/*---------------------------------------------------------------------------*/
static int      gPanel = 0;
static int      gTCPConnected = 0;
static int      gTCPConnectionHandle;
static char     gData;
static int      gTCPError = 0;

/*---------------------------------------------------------------------------*/
/* Internal function prototypes                                              */
/*---------------------------------------------------------------------------*/
static int CVICALLBACK TCPCallback (unsigned int handle, int xType, 
    int errCode, void *callbackData);
static void ReportTCPError (void);

/*---------------------------------------------------------------------------*/
/* This is the application's entry-point.                                    */
/*---------------------------------------------------------------------------*/
int main (int argc, char *argv[])
{
    int registered = 0;
    
    if (InitCVIRTE (0, argv, 0) == 0)
        goto Done;
    
    tcpChk (RegisterTCPServer (10000, TCPCallback, 0));
    registered = 1;
    
    if ((gPanel = LoadPanel (0, "MultiThreadingServer.uir", PANEL)) < 0)
        goto Done;
    DisplayPanel (gPanel);
    RunUserInterface ();
    
Done:
    if (gPanel > 0)
        DiscardPanel (gPanel);
    if (registered)
        UnregisterTCPServer (10000);
    return 0;
}

/*---------------------------------------------------------------------------*/
/* Respond to the panel closure to quit the UI loop.                         */
/*---------------------------------------------------------------------------*/
int CVICALLBACK PanelCallback (int panel, int event, void *callbackData,
        int eventData1, int eventData2)
{
    switch (event)
        {
        case EVENT_CLOSE:
            QuitUserInterface (0);
            break;
        }
    return 0;
}

/*---------------------------------------------------------------------------*/
/* Send data to connected client on each timer tick event.                   */
/*---------------------------------------------------------------------------*/
int CVICALLBACK TimerCallback (int panel, int control, int event,
        void *callbackData, int eventData1, int eventData2)
{
    switch (event)
        {
        case EVENT_TIMER_TICK:
            if (gTCPConnected)
                {
                /* Client is connected. Generate and send data. */
                gData = (char)(rand() % 128);
                tcpChk (ServerTCPWrite (gTCPConnectionHandle, &gData, 
                    sizeof (gData), 0));
                PlotStripChartPoint (gPanel, PANEL_CHART, (double)gData);
                }
            break;
        }
    
Done:   
    return 0;
}

/*---------------------------------------------------------------------------*/
/* TCP callback function.                                                    */
/*---------------------------------------------------------------------------*/
static int CVICALLBACK TCPCallback (unsigned int handle, int xType, 
    int errCode, void *callbackData)
{
    switch (xType)
        {
        case TCP_CONNECT:
            if (gTCPConnected)
                {
                /* There is an existing client. Disconnect new client. */
                tcpChk (DisconnectFromTCPServer (handle));
                }
            else
                {
                /* Accept new connection, as there is no existing client. */
                gTCPConnectionHandle = handle;
                gTCPConnected = 1;
                SetCtrlAttribute (gPanel, PANEL_TIMER, ATTR_ENABLED, 1);
                }
            break;
        case TCP_DISCONNECT:
            if (gTCPConnected && handle == gTCPConnectionHandle)
                {
                /* Client disconnected. */
                SetCtrlAttribute (gPanel, PANEL_TIMER, ATTR_ENABLED, 0);
                gTCPConnected = 0;
                }
            break;
        case TCP_DATAREADY:
            /* Ignore any data sent to server. */
            break;
        }
        
Done:   
    return 0;
}

/*---------------------------------------------------------------------------*/
/* Report TCP Errors.                                                        */
/*---------------------------------------------------------------------------*/
static void ReportTCPError (void)
{
    char    messageBuffer[1024];

    if (gTCPError < 0)
        {
        sprintf(messageBuffer, 
            "TCP library error message: %s\nSystem error message: %s", 
            GetTCPErrorString (gTCPError), GetTCPSystemErrorString());
        MessagePopup ("Error", messageBuffer);
        gTCPError = 0;
        }
}
/*---------------------------------------------------------------------------*/