udpServer.c

#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <mex.h>

#define BUFLEN 177
#define NUMSAMPLESRX 500
#define PORT 9930

void diep(char *s)
{
    perror(s);
    exit(1);
}

void udpOpen(int *s)
{
    
    struct sockaddr_in si_me;
    int s_in, i;
    
    if ((s_in=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
        diep("socket");
    
    printf("Open socket %d\n",s_in);
    memset((char *) &si_me, 0, sizeof(si_me));
    si_me.sin_family = AF_INET;
    si_me.sin_port = htons(PORT);
    si_me.sin_addr.s_addr = htonl(INADDR_ANY);
    if (bind(s_in, &si_me, sizeof(si_me))==-1)
        diep("bind");
    
    memcpy(s,&s_in,sizeof(s_in));
    
}

void udpReceive(int s, unsigned char* data)
{
    struct sockaddr_in si_other;
    int slen=sizeof(si_other), st, i;    
    
    for (i=0;i<NUMSAMPLESRX;i++) {
        unsigned char buf[BUFLEN];
        
        if (recvfrom(s, buf, BUFLEN, 0, &si_other, &slen)==-1)
            diep("recvfrom()");
                
        st=i*BUFLEN;
        memcpy(&data[st],buf,BUFLEN);
    }
}

void udpClose(int s)
{
    printf("Closing socket %d\n",s);
    close(s);
}

/*
 * void udpServer(unsigned char* data)
 * {
 * struct sockaddr_in si_me, si_other;
 * int s, i, slen=sizeof(si_other);
 * unsigned char buf[BUFLEN];
 *
 * if ((s=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
 * diep("socket");
 *
 * memset((char *) &si_me, 0, sizeof(si_me));
 * si_me.sin_family = AF_INET;
 * si_me.sin_port = htons(PORT);
 * si_me.sin_addr.s_addr = htonl(INADDR_ANY);
 * if (bind(s, &si_me, sizeof(si_me))==-1)
 * diep("bind");
 *
 *
 * if (recvfrom(s, buf, BUFLEN, 0, &si_other, &slen)==-1)
 * diep("recvfrom()");
 * printf("Received packet from %s:%d\nData: %s\n\n",
 * inet_ntoa(si_other.sin_addr), ntohs(si_other.sin_port), buf);
 *
 *
 * memcpy(data,buf,BUFLEN);
 * close(s);
 * }
 */

void mexFunction( int nlhs, mxArray *plhs[],
        int nrhs, const mxArray *prhs[])
{
    
    char fun[81];
    mwSize strlen=mxGetN(prhs[0])+1;
    mxGetString(prhs[0],fun,strlen);
    /* printf("%s\n",fun); */
    
    if (strcmp(fun,"Open")==0) {
        int *s;
        plhs[0]=mxCreateNumericMatrix(1,1,mxINT64_CLASS,0);
        s=mxGetData(plhs[0]);
        
        mexLock();
        udpOpen(s);
    }
    
    if (strcmp(fun,"Receive")==0) {
        unsigned char* data;
        int s;
        plhs[0] = mxCreateNumericMatrix(1,BUFLEN*NUMSAMPLESRX, mxUINT8_CLASS, mxREAL);
        data = mxGetData(plhs[0]);
        s=mxGetScalar(prhs[1]);
        
        udpReceive(s,data);
    }
    
    if (strcmp(fun,"Close")==0) {
        int s;
        s=mxGetScalar(prhs[1]);
        
        udpClose(s);
        mexUnlock();
    }
}