/**
* Unlike accessing the peer database, this only returns currently
* connected peers and includes data not yet saved in the peer db.
*/
fc::vector<db::peer::record> node::active_peers()const {
if( !my->_thread.is_current() ) {
return my->_thread.async( [this](){ return active_peers(); } ).wait();
}
fc::vector<db::peer::record> recs(my->_dist_to_con.size());
auto itr = my->_dist_to_con.begin();
auto end = my->_dist_to_con.end();
int i = 0;
while( itr != end ) {
recs[i] = itr->second->get_db_record();
++i;
++itr;
}
return recs;
}
void* draw_state() {
printf("\033[2J\033[1;1H");
int pieces = file_length/piece_length+1;
printf("%d byte file, %d byte pieces, %d pieces, %d active, %d choked\n",
file_length,piece_length,file_length/piece_length+1,active_peers(),choked_peers());
for(int i=0;i<pieces;i++) {
if(i%80 == 0) printf("\n");
switch(piece_status[i]) {
case PIECE_EMPTY: printf("."); break;
case PIECE_PENDING: printf("x"); break;
case PIECE_FINISHED: printf("X"); break;
default: printf("?");
}
}
fflush(stdout);
}
void listen_from_peers()
{
struct peer_state* peer = peers;
unsigned int msglen = 0;
while(missing_blocks() > 0)
{
fd_set fdrset_clone;
fd_set fdwset_clone;
FD_COPY(&fdrset,&fdrset_clone);
FD_COPY(&fdwset,&fdwset_clone);
int rdy = select(FD_SETSIZE,&fdrset_clone,&fdwset_clone,0, 0);
if(rdy <= 0) {
continue;
}
peer = peers;
if(active_peers() == 0){
break;
}
while(peer){
if(FD_ISSET(peer->socket,&fdwset_clone)){
if(peer->connected == 0){
//to send the handshake if it is not connected
send_handshake(peer);
}
else if(peer->send_count > 0) {
//to send the have/interested/piece messages to peers
send_buffed_msg(peer);
}
}
if(FD_ISSET(peer->socket,&fdrset_clone))
{
int newbytes = recv(peer->socket,peer->incoming+peer->count,BUFSIZE-peer->count,0);
if(newbytes <= 0){
peer->trying_to_connect = 0;
if(newbytes == 0){
piece_status[peer->requested_piece] = PIECE_EMPTY;
}
disconnet_peer(peer);
reconnect_peer(peer);
peer = peer->next;
continue;
}
peer->count += newbytes;
if(!peer->handshaked){
peer->count -= peer->incoming[0]+49;
if(peer->count) {
memmove(peer->incoming,peer->incoming + peer->incoming[0]+49,peer->count);
}
peer->handshaked = 1;
}
if(memcmp(peer->incoming+peer->incoming[0]+8+20,"-UICCS450-",strlen("-UICCS450-"))==0) {
fprintf(stderr,"Caught a CS450 peer, exiting.\n");
disconnet_peer(peer);
continue;
}
while(peer->count >= (ntohl(((int*)peer->incoming)[0])) + 4){
msglen = ntohl(((int*)peer->incoming)[0]);
switch(peer->incoming[4]) {
// CHOKE
case 0: {
if(debug)
fprintf(stderr,"Choke\n");
peer->choked = 1;
piece_status[peer->requested_piece]=PIECE_EMPTY;
peer->requested_piece = -1;
break;
}
// UNCHOKE
case 1: {
if(debug)
fprintf(stderr,"Unchoke\n");
peer->choked = 0;
peer->requested_piece = next_piece(-1,peer);
request_block(peer,peer->requested_piece,0);
break;
}
//Interested
case 2: {
//dev_notifier();
send_choke_unchoke_msg(peer,0); //ischoked = 0
peer->not_interested = 0;
break;
}
//Not interested
case 3: {
//dev_notifier();
peer->not_interested = 1;
break;
}
// HAVE -- update the bitfield for this peer
case 4: {
int piece = ntohl(*((int*)&peer->incoming[5]));
int bitfield_byte = piece/8;
int bitfield_bit = piece%8;
if(debug)
fprintf(stderr,"Have %d\n",piece);
peer->bitfield[bitfield_byte] |= 1 << (7 - bitfield_bit);
piece_occurence_value[piece]++;
send_interested(peer);
break;
}
// BITFIELD -- set the bitfield for this peer
case 5:
//peer->choked = 0; //commenting it according to prof's note in class
if(debug)
printf("Bitfield of length %d\n",msglen-1);
int fieldlen = msglen - 1;
if(fieldlen != (file_length/piece_length/8+1)) {
disconnet_peer(peer);
if(active_peers() == 0){
break;
}
peer = peer->next;
continue;
}
memcpy(peer->bitfield,peer->incoming+5,fieldlen);
read_bit_maps(peer->bitfield,fieldlen);
send_interested(peer);
break;
//Request piece
case 6: {
if(peer->i_choked_it == 1)
break;
decode_request_send_piece_to_peer(peer);
}
break;
// PIECE
case 7: {
//make the tit for tatter
peer->send_recv_balancer++;
if(peer->i_choked_it && peer->send_recv_balancer == 0){
peer->i_choked_it = 0;
send_choke_unchoke_msg(peer,0); //unchoke peer
}
int piece = ntohl(*((int*)&peer->incoming[5]));
int offset = ntohl(*((int*)&peer->incoming[9]));
int datalen = msglen - 9;
fprintf(stderr,"Writing piece %d, offset %d, ending at %d\n",piece,offset,piece*piece_length+offset+datalen);
write_block(peer->incoming+13,piece,offset,datalen,1);
draw_state();
offset+=datalen;
if(offset==piece_length || (piece*piece_length+offset == file_length) ) {
broadcast_have_msg(piece);
draw_state();
if(debug)
fprintf(stderr,"Reached end of piece %d at offset %d\n",piece,offset);
peer->requested_piece=next_piece(piece,peer);
offset = 0;
}
request_block(peer,peer->requested_piece,offset);
break;
}
}
drop_message(peer);
}
}
peer = peer->next;
}
}
return;
}