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/* test multicast */
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/if_ether.h>
#include <netinet/in.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <time.h>
#include <signal.h>
#include <errno.h>
#include <linux/ax25.h>
#ifndef AX25_MTU
#define AX25_MTU 256
#endif
#include <netdb.h>
#include "libax25ext.h"
static void
die(char *p, char *s)
{
fprintf(stderr,"%s: ",p);
perror(s);
exit(1);
}
main(int argc,char **argv)
{
struct sockaddr_in sin;
struct sockaddr tsa, rsa;
struct hostent *hp;
struct servent *sp;
char *name = argv[1], *service = argv[2], *ttl = argv[3];
const int one=1;
int ttlval;
int tsock, rsock;
unsigned char buffer[AX25_MTU];
int selfds = 0;
fd_set select_mask;
if (argc < 4 || (ttlval = atoi(ttl)) <= 0) {
fprintf(stderr,"Usage: %s destination port ttl\n",argv[0]);
exit(1);
}
fprintf(stderr,"opening UDP socket on %s/%s/%d\n", name, service, ttlval);
bzero(&sin, sizeof(struct sockaddr_in));
if (isdigit(*name)) {
sin.sin_addr.s_addr = inet_addr(name);
}
else if (hp = gethostbyname(name)) {
bcopy(hp->h_addr, (char *)&sin.sin_addr, hp->h_length);
}
else {
fprintf(stderr,"Unrecognized host name: %s\n",name);
exit(1);
}
if (isdigit(*service)) {
sin.sin_port = htons(atoi(service));
}
else if (sp = getservbyname(service,"udp")) {
sin.sin_port = sp->s_port;
}
else {
fprintf(stderr,"Unrecognized service: %s\n",service);
exit(1);
}
sin.sin_family = AF_INET;
if (argc == 4) {
if ((tsock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
perror(name);
exit(1);
}
if (setsockopt(tsock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) < 0)
die("setsockopt SO_REUSEADDR",name);
if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
if (setsockopt(tsock, SOL_IP, IP_MULTICAST_TTL, &ttlval, sizeof(ttlval)) < 0)
die("setsockopt MULTICAST_TTL",name);
} else {
if (setsockopt(tsock, SOL_IP, IP_TTL, &ttlval, sizeof(ttlval)) < 0)
die("setsockopt IP_TTL",name);
}
bzero(&tsa,sizeof(tsa));
bcopy(&sin,&tsa,sizeof(sin)); /* fill sockaddr w/sockaddr_in */
}
if (argc == 4) {
if (connect(tsock, &tsa, sizeof(struct sockaddr)) < 0) {
die("connect(tsock)",name);
}
}
/* now the rsock */
if ((rsock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
die("rsock = socket",name);
}
if (setsockopt(rsock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) < 0)
die("rsock SO_REUSEADDR",name);
/* if the UDP socket is a multicast group, then do IGMP join for rsock */
if (!IN_MULTICAST(ntohl(sin.sin_addr.s_addr)))
sin.sin_addr.s_addr = INADDR_ANY;
bzero(&rsa,sizeof(rsa));
bcopy(&sin,&rsa,sizeof(sin));
if (bind(rsock, &rsa, sizeof(struct sockaddr)) < 0) {
die("bind(rsock)",name);
}
if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
struct ip_mreq mreq;
mreq.imr_multiaddr = sin.sin_addr;
mreq.imr_interface.s_addr = INADDR_ANY;
setsockopt(rsock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
}
/* sockets set up, enter loop, receiving from stdin & rsock,
transmitting what's read from stdin on tsock */
/* set up the initial select mask */
FD_ZERO(&select_mask);
FD_SET(rsock, &select_mask);
FD_SET(0, &select_mask);
selfds = rsock+1;
for (;;) {
int len;
fd_set rmask = select_mask;
int size = sizeof(struct sockaddr);
fprintf(stderr,"before select rsock=%d rmask=0x%0x\n",rsock,rmask);
if (select(selfds,&rmask,NULL,NULL,NULL) < 0) {
if (errno == EINTR)
continue;
perror("select");
return 1;
}
fprintf(stderr,"after select rmask=0x%0x\n",rmask);
/* find which sockets have data */
if (FD_ISSET(rsock,&rmask)) {
fprintf(stderr,"rsock was set\n");
if ((len = recvfrom(rsock,buffer,sizeof(buffer),0,&rsa,&size)) < 0) {
if (errno == EINTR)
continue;
perror(name);
exit(1);
}
fprintf(stderr,"rsock rec'd %d: %s\n",len,buffer);
}
if (FD_ISSET(0,&rmask)) {
int r;
fprintf(stderr,"stdin was set\n");
if ((len = read(0,buffer,sizeof(buffer))) < 0) {
perror("stdin");
exit(1);
}
fprintf(stderr,"stdin read %d: %s\n",len,buffer);
/* now xmit it */
if ((r = sendto(tsock,buffer,len,0,&tsa,sizeof(tsa))) < 0)
die("sendto","xmit");
fprintf(stderr,"transmitted %d\n",r);
}
} /* end of for(;;) */
return 0; /* NOTREACHED */
}
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