static EVENT_HANDLER(transmit)
{
WLAN_FRAME frame;
int link = 1;
// POPULATE A NEW FRAME
do {
frame.header.dest = CNET_rand() % NNODES;
} while(frame.header.dest == nodeinfo.nodenumber);
frame.header.src = nodeinfo.nodenumber;
frame.header.prevpos = positions[nodeinfo.nodenumber]; // me!
sprintf(frame.payload, "hello from %d", nodeinfo.nodenumber);
frame.header.length = strlen(frame.payload) + 1; // send nul-byte too
// TRANSMIT THE FRAME
size_t len = sizeof(WLAN_HEADER) + frame.header.length;
CHECK(CNET_write_physical_reliable(link, &frame, &len));
++stats[0];
if(verbose) {
fprintf(stdout, "\n%s: transmitting '%s' to %d\n",
nodeinfo.nodename, frame.payload, frame.header.dest);
}
// SCHEDULE OUR NEXT TRANSMISSION
CNET_start_timer(EV_TIMER1, TX_NEXT, 0);
}
///Worker Method
///Called to send a nl_packet to an associated access point.
///If this device is not associated, we abort and manage association instead
///as there is nowhere to transmit the packet to.
static int transmit(struct nl_packet *packet)
{
fprintf(stdout, "\tTransmitting.\n");
// Create a broadcast address.
CnetNICaddr wifi_dest;
CHECK(CNET_parse_nicaddr(wifi_dest, "ff:ff:ff:ff:ff:ff"));
//uint16_t packet_length = NL_PACKET_LENGTH(packet);
uint16_t packet_length = sizeof(*packet);
if(packet->type == NULL_FRAME)
{
fprintf(stderr, "\t%s is attempting to send a null packet!\n",nodeinfo.nodename);
exit(0);
}
if(isAss == false)
{
fprintf(stdout, "\tWhoops! %s is not associated!\n\t Starting Probe\n", nodeinfo.nodename);
// CHECK(CNET_disable_application(ALLNODES));
probe_timer = CNET_start_timer(EV_TIMER1, 100, 0);
return 0;
}
else
{
fprintf(stdout, "\tAssociation is true, sending frame.\n");
fprintf(stdout, "\n packet src:%i dest:%i\n",packet->src, packet->dest);
if(packet->dest > 133) exit(0);
dll_wifi_write(dll_states[1], wifi_dest, (char *)packet, packet_length);
if(packet->type == NL_DATA )
{
CHECK(CNET_disable_application(ALLNODES));
printf(" DATA transmitted, seq=%d\n", packet->seq);
data_timeout = CNET_start_timer(EV_TIMER2, CNET_rand() * 50000 + 500000, 0); /// one second wait time
}
return 1;
}
}
static EVENT_HANDLER(walker)
{
static double dx = 0.0;
static double dy = 0.0;
static double newx = 0.0;
static double newy = 0.0;
static int nsteps = 0;
CnetPosition now;
CnetTime movenext;
// IF PAUSED, WE NEED TO CHOOSE A NEW DESTINATION AND WALKING SPEED
if(paused) {
CnetPosition newdest;
CHECK(CNET_get_position(&now, NULL));
// CHOOSE A NEW DESTINATION THAT DOESN'T REQUIRE WALKING THROUGH A WALL!
do {
int newspeed;
double dist;
newdest = now;
do {
choose_position(&newdest, MAX_WALK_DIST);
} while(through_an_object(now, newdest));
dx = newdest.x - now.x;
dy = newdest.y - now.y;
dist = sqrt(dx*dx + dy*dy); // only walking in 2D
newspeed = CNET_rand() % MAX_SPEED + 1;
nsteps = dist / newspeed;
} while(nsteps < 3); // ensure we'll take at least 3 steps
//draw_walk(&now, &newdest);
// CALCULATE MOVEMENTS PER STEP
dx = (dx / nsteps);
dy = (dy / nsteps);
newx = now.x;
newy = now.y;
paused = false; // and off we go....
}
// WE'RE WALKING; DO WE STILL HAVE SOME STEPS TO TAKE?
if(nsteps > 0) {
newx += dx;
newy += dy;
now.x = newx;
now.y = newy;
now.z = 0;
CHECK(CNET_set_position(now));
paused = false;
--nsteps;
movenext = WALK_FREQUENCY;
}
// WE'VE FINISHED WALKING, SO WE PAUSE HERE FOR A WHILE
else {
paused = true;
nsteps = 0;
movenext = (CNET_rand() % (MAX_PAUSE-MIN_PAUSE) + MIN_PAUSE) * 1000000;
}
// RESCHEDULE THIS WALKING EVENT
tid = CNET_start_timer(EV_WALKING, movenext, data);
}
