void init() {
char temp[1024], nick[1024], addr[1024], newaddr[NET_MAX_ADDRESS_LENGTH];
NET_DRIVERLIST drv;
drv = net_driverlist_create();
net_driverlist_clear (drv);
net_driverlist_add (drv, netdriver);
if (!net_initdrivers (drv)) {
printf("Error initialising driver.\n");
exit (1);
}
printf ("Enter target address: ");
fgets (addr, 1024, stdin);
while (strchr(addr,'\n')) *strchr(addr,'\n')=0;
printf ("Enter nickname: ");
fgets (nick, 10, stdin);
while (strchr(nick,'\n')) *strchr(nick,'\n')=0;
if (!(chan = net_openchannel (netdriver, NULL))) {
printf ("Unable to open channel.\n");
exit (2);
}
printf ("Connecting to %s...\n", addr);
net_assigntarget (chan, addr);
sprintf (temp, "%c%s", CHAT_MAGIC, nick);
net_send (chan, temp, strlen (temp));
while ((!net_query (chan))/* && !conio_kbhit()*/);
if (0/*conio_kbhit()*/) {
conio_getch();
printf ("Aborted.\n");
exit (3);
}
{
int x = net_receive (chan, temp, 1024, newaddr);
if (x == -1) {
printf ("Receive error.\n");
exit (5);
}
temp[x] = 0;
}
if (strcmp (temp, "OK")) {
printf ("Connection refused.\n");
exit (4);
}
printf ("Connection accepted, redirecting... ");
fflush (stdout);
net_assigntarget (chan, newaddr);
printf ("done.\n");
}
/* poll_listen:
* Here we check for an incoming connection, and if there is one we
* fill in `newconn' with our data pointer for it and the addresses,
* and return nonzero. Otherwise return 0.
*/
static int poll_listen (NET_CONN *conn, NET_CONN *newconn)
{
struct conn_data_t *data;
char buffer[12], buffer2[8+NET_MAX_ADDRESS_LENGTH] = { 0, 0, 0, 0, 0, 0, 0, 0 };
char addr[NET_MAX_ADDRESS_LENGTH];
int x;
int count = 32; /* maximum number of packets to process */
while (net_query (((struct conn_data_t *)conn->data)->chan) && count-- > 0) {
if ((net_receive (((struct conn_data_t *)conn->data)->chan, buffer, 12, addr) == 12) && !memcmp (buffer, "connect", 8)) {
newconn->data = data = malloc (sizeof *data);
if (!data) continue;
if (create_queues (newconn)) {
free (data);
continue;
}
data->conns = NULL;
x = get_channel (
((struct conn_data_t *)conn->data)->conns, addr,
(buffer[8] << 24) + (buffer[9] << 16) +
(buffer[10] << 8) + buffer[11],
conn->type, NULL, &data->chan, data
);
if (x) {
data->referer = conn->data;
/* tell new channel where to send in future */
net_assigntarget (data->chan, addr);
/* send reply now with address of new channel, through
* listening conn so it can get through NATs */
net_assigntarget (((struct conn_data_t *)conn->data)->chan, addr);
strcpy (buffer2+8, net_getlocaladdress (data->chan));
net_send (((struct conn_data_t *)conn->data)->chan, buffer2, 8+NET_MAX_ADDRESS_LENGTH);
}
if (x >= 0) {
destroy_queues (newconn);
free (data);
continue;
}
strcpy (newconn->peer_addr, addr);
return 1;
}
}
return 0;
}
/* connect:
* Set the target address and send the first connection request. This
* might not get through of course; later we can just repeat the send
* statement because the target address is already set. No need to store
* it anywhere.
*/
static int connect (NET_CONN *conn, const char *target)
{
int id;
static int next_id = 0;
struct conn_data_t *data = conn->data;
/* The id is a compound of the current time (with 1 second
* granularity), and an increasing counter. The time is needed
* because the counter resets when you restart the program, and
* the counter is needed because of the granularity of the time. */
/* Strictly, this line needs a mutex, but there's nowhere around
* here we can call `MUTEX_CREATE'. */
id = (next_id++ << 16) + (time(NULL) & 0xffff);
strcpy (data->connect_string, "connect");
data->connect_string[8] = (id >> 24) & 0xff;
data->connect_string[9] = (id >> 16) & 0xff;
data->connect_string[10] = (id >> 8) & 0xff;
data->connect_string[11] = id & 0xff;
if (net_assigntarget (data->chan, target)) return 1;
if (net_send (data->chan, data->connect_string, 12)) return 2;
data->connect_timestamp = __libnet_timer_func();
return 0;
}
/* poll_connect:
* This function does two things. Firstly it checks for a response from
* the server. If there's no response, it then resends the connection
* request.
*
* The possible problem here is that the server's response might just be
* delayed. The best way I can see around this problem is for the server
* to keep an eye on the return addresses of the connection attempts, and
* not open a fresh channel each time a duplicate of an old packet arrives.
* This actually kills two birds with one stone, since if either the
* client's request packet or the server's response packet are dropped, the
* client will eventually resend, causing the server to send an identical
* response.
*
* Later note: In fact we needed to introduce an almost-unique identifier
* to pass as well, since the channel's address may be reused later on.
*/
static int poll_connect (NET_CONN *conn)
{
struct conn_data_t *data = conn->data;
char buffer[8+NET_MAX_ADDRESS_LENGTH];
char addr[NET_MAX_ADDRESS_LENGTH];
if ((net_receive (data->chan, buffer, 8+NET_MAX_ADDRESS_LENGTH, addr) == 8+NET_MAX_ADDRESS_LENGTH) && (!memcmp (buffer, "\0\0\0\0\0\0\0", 8))) {
net_fixupaddress_channel(data->chan, &buffer[8], addr);
net_assigntarget (data->chan, addr);
strcpy (conn->peer_addr, addr);
return 1;
}
/* No response */
{
unsigned long clock_value = __libnet_timer_func();
if ((unsigned)(clock_value - data->connect_timestamp) > RESEND_RATE) {
net_send (data->chan, data->connect_string, 8);
data->connect_timestamp = clock_value;
}
}
return 0;
}
int main (int argc, char **argv)
{
NET_CONN *listen, *conn = NULL;
NET_CHANNEL *chan;
char remote[NET_MAX_ADDRESS_LENGTH], buf[NET_MAX_ADDRESS_LENGTH];
char *p, c;
int server = -1;
if (argc > 1) {
if (!strcmp (argv[1], "server")) server = 1;
else if (!strcmp (argv[1], "client")) server = 0;
}
if (server == -1) {
puts ("Pass `server' or `client' on the command line.");
return 1;
}
net_init();
net_detectdrivers(net_drivers_all);
net_initdrivers(net_drivers_all);
if (server) {
listen = net_openconn(DRIVER, "");
net_listen(listen);
while (!conn)
conn = net_poll_listen(listen);
} else {
conn = net_openconn(DRIVER, NULL);
if (net_connect_wait_time(conn, ADDRESS, 5) != 0) {
printf("Error connecting\n");
return 1;
}
}
chan = net_openchannel(DRIVER, NULL);
p = net_getlocaladdress(chan);
net_send_rdm(conn, p, strlen(p) + 1);
while (!net_query_rdm(conn)) ;
net_receive_rdm(conn, remote, sizeof remote);
printf ("Address before fixing: %s\n", remote);
if (net_fixupaddress_conn(conn, remote, buf) != 0) {
printf("Didn't work\n");
return 1;
}
printf ("Address after fixing: %s\n", buf);
printf("assigning target: %s\n", buf);
net_assigntarget(chan, buf);
do {
c = fgetc(stdin);
if (c == '1')
net_send(chan, "** Channel", 11);
else if (c == '2')
net_send_rdm(conn, "** Conn", 8);
while (net_query(chan)) {
net_receive(chan, buf, sizeof buf, NULL);
printf("%s\n", buf);
}
while (net_query_rdm(conn)) {
net_receive_rdm(conn, buf, sizeof buf);
printf("%s\n", buf);
}
} while (c != 'q');
return 0;
}
