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|
use bufio;
use bytes;
use errors;
use fmt;
use fs;
use io;
use net::ip;
use net::tcp;
use net;
use os;
use strings;
use time::chrono;
use time::date;
use time;
use unix::poll;
use drawing;
use drawing::{pos};
use packet_reader;
def PORT: u16 = 41460;
def CHUNKSIZE = 512;
type server_state = struct {
connections: []connection,
pictures: []drawing::picture,
listener: net::socket,
running: bool
};
type connection = struct {
pr: packet_reader::packet_reader,
sock: net::socket,
pos: pos,
should_delete: bool,
};
def save_interval = 20 * time::SECOND;
export fn main() void = {
// create 4 pictures. later we will have more pictures
// but for now there are just 4, and they are at fixed positions
const offs: [_]pos = [
(0,0), (0,CHUNKSIZE), (CHUNKSIZE,0), (CHUNKSIZE,CHUNKSIZE),
];
let pictures: []drawing::picture = alloc([],len(offs));
for (let i = 0z; i < len(offs); i +=1){
append(pictures, match (load_picture_from_file(offs[i])) {
case let pic: drawing::picture => yield pic;
case let err: fs::error => fmt::fatal(fs::strerror(err));
case bad_header => fmt::fatal("bad ppm header");
});
};
const listener = match (
tcp::listen(ip::ANY_V4, PORT, tcp::reuseaddr)
) {
case let err: net::error =>
fmt::fatalf(net::strerror(err));
case let sock: net::socket =>
yield sock;
};
let state = server_state {
connections = [],
pictures = pictures,
listener = listener,
running = true,
};
let now = time::now(time::clock::MONOTONIC);
let next = time::add(now, save_interval);
for (state.running) {
const timeout = time::diff(now, next);
fmt::println("running loop, timeout {}",timeout)!;
loop(&state, timeout);
now = time::now(time::clock::MONOTONIC);
if (time::compare(now, next) >= 0) {
fmt::println("saving world!")!;
match (save_world(&state)) {
case let e: fs::error =>
fmt::fatalf("couldn't save world: {}",fs::strerror(e));
case void => yield;
};
next = time::add(now, save_interval);
};
};
};
fn loop(state: *server_state, timeout: time::duration) void = {
// do poll.
let pollfds: []poll::pollfd = [];
append(pollfds, poll::pollfd {
fd = state.listener,
events = poll::event::POLLIN,
...
});
for (const conn &.. state.connections) {
append(pollfds, poll::pollfd {
fd = conn.sock,
events = poll::event::POLLIN,
...
});
};
poll::poll(pollfds, timeout)!;
// if listener: add connection
if (0 != pollfds[0].revents & poll::event::POLLIN) {
const new_conn = tcp::accept(pollfds[0].fd)!;
append(state.connections, connection {
sock = new_conn,
pr = packet_reader::new(),
pos = (0,0),
should_delete = false,
});
fmt::printfln("there are now {} connections",
len(state.connections))!;
greet_connection(state, len(state.connections));
};
// for each connection, handle packet(s)
// loop thru pollfds not state.connections so we don't
// try to look at the nonexistent pollfd for a connection we just accepted
for (let pollfd_idx = 1z: size; pollfd_idx < len(pollfds); pollfd_idx += 1) {
const conn_idx = pollfd_idx - 1;
fmt::println("checking conn {} with pollfd {}",conn_idx, pollfd_idx)!;
if (0 != pollfds[conn_idx+1].revents & poll::event::POLLIN) {
read_from_connection(state, conn_idx);
};
};
perform_deletions(state);
};
fn perform_deletions(state: *server_state) void = {
for (let i1 = len(state.connections); i1 > 0; i1 -= 1) {
const i = i1 - 1;
const conn = state.connections[i];
if (conn.should_delete) {
fmt::printfln("deleting conn {}",i)!;
delete(state.connections[i]);
};
};
};
fn greet_connection(state: *server_state, conn_idx: size) void = void;
fn read_from_connection(state: *server_state, conn_idx: size) void = {
const conn = &state.connections[conn_idx];
match (packet_reader::read(&conn.pr, conn.sock)) {
case let err: io::error =>
fmt::printfln("#{} error: {}", conn_idx, io::strerror(err))!;
conn.should_delete = true;
case io::EOF =>
fmt::printfln("#{} disconnect", conn_idx)!;
conn.should_delete = true;
case void =>
for (true) match (packet_reader::next(&conn.pr)) {
// foreach loop seems to break match exhaustivity here
case done => break;
case let p: packet_reader::packet =>
handle_packet(state, conn_idx, p);
case let e: packet_reader::error =>
fmt::printfln("packet error {}",e)!;
conn.should_delete = true;
};
};
};
fn handle_packet(
state: *server_state,
conn_idx: size,
packet: packet_reader::packet
) void = {
match (packet) {
case let op: packet_reader::packet_drawop =>
const opc = op as drawing::op_circle;
fmt::printfln("#{}: drawop ({:+6},{:+6})",conn_idx,opc.0,opc.1)!;
drawing::perform(state.pictures, opc);
for (let other_idx = 0z;
other_idx < len(state.connections);
other_idx += 1)
{
if (other_idx == conn_idx) continue;
const other_conn = &state.connections[other_idx];
if (other_conn.should_delete) continue;
fmt::printfln("\t -> #{}",other_idx)!;
match (packet_reader::send(other_conn.sock, packet)) {
case void => yield;
case let e: io::error =>
fmt::printfln("couldn't send to #{}: {}",
other_idx, io::strerror(e))!;
other_conn.should_delete = true;
};
};
case =>
fmt::printfln("shouldn't be getting other packets from #{}",conn_idx)!;
state.connections[conn_idx].should_delete = true;
};
};
fn send_world(conn: io::file, pictures: []drawing::picture) (void | io::error) = {
for (const pic &.. pictures) {
fmt::printfln(" sending {},{}",pic.world_pos.0, pic.world_pos.1)!;
packet_reader::send(conn, packet_reader::packet_sendchunk {
world_pos = pic.world_pos,
chunk_data = pic.d[..pic.w*pic.h],
})?;
};
};
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