Subversion Repositories funbase_ip_library

// udp_lite.c - LM

#include <stdio.h>      /* for printf() and fprintf() */

#include <sys/socket.h> /* for socket() and bind() */

#include <arpa/inet.h>  /* for sockaddr_in and inet_ntoa() */

#include <stdlib.h>     /* for atoi() and exit() */

#include <string.h>     /* for memset() */

#include <unistd.h>     /* for close() */

#define ServPort 6000

int sock;                        /* Socket */

struct sockaddr_in ServAddr; /* Local address */

struct sockaddr_in ClntAddr; /* Client address */

unsigned int cliAddrLen;         /* Length of incoming message */

char Buffer[maxBuffer];        /* Buffer for echo string */

unsigned short ServPort;     /* Server port */

int recvMsgSize;                 /* Size of received message */

void create_socket()

{

    /* Create socket for sending/receiving datagrams */

    if ((sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)

        DieWithError("socket() failed");

    /* Construct local address structure */

    memset(&ServAddr, 0, sizeof(ServAddr));   /* Zero out structure */

    ServAddr.sin_family = AF_INET;                /* Internet address family */

    ServAddr.sin_addr.s_addr = htonl(INADDR_ANY); /* Any incoming interface */

    ServAddr.sin_port = htons(ServPort);      /* Local port */

    /* Bind to the local address */

    if (bind(sock, (struct sockaddr *) &echoServAddr, sizeof(echoServAddr)) < 0)

        DieWithError("bind() failed");

}

void udp_send(buffer, buffer_size)

{

   /* Send datagrams to the client */

    if (sendto(sock, buffer, buffer_size, 0,

               (struct sockaddr *) &ClntAddr, sizeof(ClntAddr)) != MsgSize)

            DieWithError("sendto() sent a different number of bytes than expected");

    }

    /* NOT REACHED */

}

void udp_recv(){

  /* Block until receive message from a client */

  if ((recvMsgSize = recvfrom(sock, Buffer, maxBuffer, 0,

  (struct sockaddr *) &echoClntAddr, &cliAddrLen)) < 0)

    DieWithError("recvfrom() failed");

}