Interface* discoverInterfaces(Config *config, bool shouldBind) {
struct ifi_info *ifi, *ifihead;
struct sockaddr *sa;
bool insert = false;
int server_fd = 0;
// Create memory for the list.
Interface *list = NULL;
// Use crazy code to loop through the interfaces
for (ifihead = ifi = Get_ifi_info_plus(AF_INET, 1); ifi != NULL; ifi = ifi->ifi_next) {
// Create node
Interface *node = malloc(sizeof(Interface));
insert = false;
// Null out pointers
node->next = NULL;
node->prev = NULL;
// Copy the name of the interface
strcpy(node->name, ifi->ifi_name);
// Copy the IPAddress
if((sa = ifi->ifi_addr) != NULL) {
strcpy(node->ip_address, Sock_ntop_host(sa, sizeof(*sa)));
}
// Copy the network mask
if((sa = ifi->ifi_ntmaddr) != NULL) {
strcpy(node->network_mask, Sock_ntop_host(sa, sizeof(*sa)));
}
// Print out info
info("<%s> [%s%s%s%s%s\b] IP: %s Mask: %s\n",
node->name,
ifi->ifi_flags & IFF_UP ? "UP " : "",
ifi->ifi_flags & IFF_BROADCAST ? "BCAST " : "",
ifi->ifi_flags & IFF_MULTICAST ? "MCAST " : "",
ifi->ifi_flags & IFF_LOOPBACK ? "LOOP " : "",
ifi->ifi_flags & IFF_POINTOPOINT ? "P2P " : "",
node->ip_address,
node->network_mask);
if(shouldBind) {
/* Config was successfully parsed; attempt to bind sockets */
server_fd = createServer(node->ip_address, config->port);
if(server_fd != SERVER_SOCKET_BIND_FAIL) {
node->sockfd = server_fd;
insert = true;
} else {
/* Unable to bind socket to port */
fprintf(stderr, "Failed to bind socket: %s:%u\n", node->ip_address, config->port);
}
} else {
insert = true;
}
// If all was successful insert into the list
if(insert) {
if(list == NULL) {
list = node;
} else {
// Just push it down the list
// IE: It goes in reverse discovery order
node->next = list;
list->prev = node;
list = node;
}
}
}
free_ifi_info_plus(ifihead);
return list;
}
int main(int argc, char** argv) {
struct datagram conn_gram;
struct ifi_info *ifihead, *ifi;
struct sockaddr_in servaddr;
struct sockaddr_in cliaddr;
fd_set rset, allset;
socklen_t len;
ssize_t n;
int nready;
int on = 1;
int maxfdp1 = 0;
int i;
int send_flag;
pid_t pid;
ifihead = get_ifi_head();
printf("Server IP Addresses:\n");
print_ifi_info(ifihead);
readfile();
printf("Listening port %d\n", port);
count = 0;
for (ifi=ifihead;ifi!=NULL;ifi=ifi->ifi_next) {
if (!(ifi->ifi_flags & IFF_UP))
continue;
addrs[count] = ifi;
sockfds[count] = Socket(AF_INET, SOCK_DGRAM, 0);
if (sockfds[count] > maxfdp1)
maxfdp1 = sockfds[count];
Setsockopt(sockfds[count], SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
memcpy(&servaddr, ifi->ifi_addr, sizeof(servaddr));
servaddr.sin_port = htons(port);
Bind(sockfds[count], (SA *) &servaddr, sizeof(servaddr));
count++;
if (count >= MAX_IFI_COUNT)
break;
}
FD_ZERO(&allset);
FD_ZERO(&rset);
for (i=0;i<count;i++) {
FD_SET(sockfds[i], &allset);
}
maxfdp1 = maxfdp1+1;
signal(SIGCHLD, sigchld);
for(;;) {
rset = allset;
if ((nready = select(maxfdp1, &rset, NULL, NULL, NULL)) < 0) {
if (errno == EINTR)
continue;
else
err_sys("select error");
}
for (i=0;i<count;i++) {
if (FD_ISSET(sockfds[i], &rset)) {
len = sizeof(cliaddr);
n = recv_from(sockfds[i], &conn_gram, &cliaddr, &len);
send_flag = get_flag(&conn_gram);
if (!n || (send_flag & RETRY)) {
// client timeout, don't fork new child
continue;
}
printf("Client [%s:%d] connected\n", inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port));
pid = fork();
if (!pid) {
child(i, &cliaddr, &conn_gram);
// exit
return 0;
}
}
}
}
free_ifi_info_plus(ifihead);
return 0;
}
