server.c

#include <assert.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include <netinet/in.h>
#include <stdio.h>

#include "spiffy.h"

#define PACKETLEN 1500
#define BUFLEN 100

typedef struct header_s {
    short magicnum;
    char version;
    char packet_type;
    short header_len;
    short packet_len; 
    u_int seq_num;
    u_int ack_num;
} header_t;  

typedef struct data_packet {
    header_t header;
    char data[BUFLEN];
} data_packet_t;


int main(int argc, char **argv) {
    struct sockaddr_in addr, from;
    socklen_t fromlen;
    char buf[PACKETLEN];
    int sock;
    struct sockaddr_in myaddr;
    fd_set readfds;
    struct user_iobuf *userbuf;
    int fd = socket(AF_INET, SOCK_DGRAM, 0);
    data_packet_t *curr;
        
    if (argc < 3) {
        printf("usage: %s <node id> <port>\n", argv[0]);
        return 1;
    }
        
    bzero(&myaddr, sizeof(myaddr));
    myaddr.sin_family = AF_INET;
    inet_aton("127.0.0.1", &myaddr.sin_addr);
    myaddr.sin_port = htons(atoi(argv[2]));
    
    if (bind(fd, (struct sockaddr *) &myaddr, sizeof(myaddr)) == -1) {
        perror("peer_run could not bind socket");
    }
    
    /* init spiffy */
    spiffy_init(atoi(argv[1]), (struct sockaddr *) &myaddr, sizeof(myaddr));

    while (1) {
        int nfds;
        FD_SET(fd, &readfds);
        
        nfds = select(fd+1, &readfds, NULL, NULL, NULL);
        
        if (nfds > 0) {
        spiffy_recvfrom(fd, buf, BUFLEN, 0, (struct sockaddr *) &from, &fromlen);   
        curr = (data_packet_t*)buf;
        printf("MAGIC: %d\n", ntohs((curr->header).magicnum));
        fflush(stdout);
        }
    // check timers
    }

    return 0;
}