1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
use std::{
collections::HashMap,
net::SocketAddr,
sync::{Arc, Weak},
time::{Duration, UNIX_EPOCH},
};
use tokio::{
net::UdpSocket,
sync::{
mpsc::{channel, Receiver, Sender, UnboundedReceiver},
Mutex,
},
};
use tokio::{
select,
sync::{
mpsc::{unbounded_channel, UnboundedSender},
RwLock,
},
};
type ClientMap = Arc<RwLock<HashMap<SocketAddr, UdpStream>>>;
type WeakClientMap = Weak<RwLock<HashMap<SocketAddr, UdpStream>>>;
pub struct UdpListener {
clients: ClientMap,
client_returner: UnboundedReceiver<UdpStream>,
no_more_clients: Receiver<String>,
}
#[derive(Clone)]
pub struct UdpStream {
pub addr: SocketAddr,
to_main_sock: UnboundedSender<Vec<u8>>,
from_main_sock_listener: Arc<Mutex<UnboundedReceiver<Vec<u8>>>>,
from_main_sock_sender: UnboundedSender<Vec<u8>>,
last_msg_time: u64,
disconnect_notifier_main_tx: Sender<()>,
disconnect_notifier_client_notifier: Arc<Mutex<Receiver<()>>>,
}
impl UdpStream {
pub async fn read(&mut self) -> Option<Vec<u8>> {
let mut data = self.from_main_sock_listener.lock().await;
let mut disconnect = self.disconnect_notifier_client_notifier.lock().await;
select! {
d = data.recv()=>d,
_ = disconnect.recv() => None
}
}
pub async fn send(&mut self, data: &[u8]) -> Option<usize> {
let len = data.len();
self.to_main_sock.send(data.to_vec()).ok().map(|_| len)
}
}
impl UdpListener {
pub fn new(sock: UdpSocket, buf_len: usize, client_timeout: usize) -> Self {
let clients: ClientMap = Default::default();
let AcceptResult {
new_client,
no_more_accepts,
} = internal_accept_start(clients.clone(), sock, buf_len, client_timeout);
let l = UdpListener {
clients,
client_returner: new_client,
no_more_clients: no_more_accepts,
};
l
}
pub async fn active_connections(&self) -> usize {
self.clients.read().await.len()
}
pub async fn accept(&mut self) -> Result<UdpStream, String> {
select! {
client = self.client_returner.recv() =>{
client.ok_or(String::from("client channel has been closed"))
}
err = self.no_more_clients.recv() => Err(err.unwrap_or(String::from("an error occured but for some reason the channel too died on the way")))
}
}
}
struct AcceptResult {
new_client: UnboundedReceiver<UdpStream>,
no_more_accepts: Receiver<String>,
}
fn internal_accept_start(
clients: ClientMap,
sock: UdpSocket,
buf_len: usize,
client_timeout: usize,
) -> AcceptResult {
let clients = Arc::downgrade(&clients);
let (client_notifier_tx, client_notifier_rx) = unbounded_channel();
let (notx, norx) = channel(1);
let sock = Arc::new(sock);
reader(
sock.clone(),
buf_len,
clients.clone(),
client_notifier_tx,
notx.clone(),
client_timeout,
);
AcceptResult {
new_client: client_notifier_rx,
no_more_accepts: norx,
}
}
fn reader(
sock: Arc<UdpSocket>,
buf_len: usize,
clients: WeakClientMap,
client_notifier_tx: UnboundedSender<UdpStream>,
notx: Sender<String>,
client_timeout: usize,
) {
tokio::task::spawn(async move {
let mut buf = vec![0; buf_len];
while let Ok((n, addr)) = sock.recv_from(&mut buf).await {
if let Some(clients_strong) = clients.upgrade() {
let mut clients_map = clients_strong.write().await;
let main_sock = sock.clone();
if let Some(sock) = clients_map.get_mut(&addr) {
sock.last_msg_time = UNIX_EPOCH.elapsed().unwrap().as_secs();
if let Err(_) = sock.from_main_sock_sender.send(buf[..n].to_vec()) {
clients_map.remove(&addr);
}
} else {
let (from_self_tx, mut from_self_rx) = unbounded_channel();
let (dis_tx, mut dis_rx) = channel(1);
let (from_main_sock_tx, from_main_sock_rx) = unbounded_channel();
let (dis_client_tx, dis_client_rx) = channel(1);
let sock = UdpStream {
addr: addr.clone(),
to_main_sock: from_self_tx.clone(),
last_msg_time: UNIX_EPOCH.elapsed().unwrap().as_secs(),
disconnect_notifier_main_tx: dis_tx,
from_main_sock_listener: Arc::new(Mutex::new(from_main_sock_rx)),
from_main_sock_sender: from_main_sock_tx.clone(),
disconnect_notifier_client_notifier: Arc::new(Mutex::new(dis_client_rx)),
};
let _ = client_notifier_tx.send(sock.clone());
clients_map.insert(addr.clone(), sock);
let _ = from_main_sock_tx.send(buf[..n].to_vec());
drop(clients_map);
let clients = clients.clone();
tokio::spawn(async move {
loop {
select! {
data = from_self_rx.recv() =>{
if let Some(data) = data{
if let Err(_) = main_sock.send_to(&data,addr).await{
cleanup(clients,&addr,dis_client_tx.clone()).await;
break;
};
}
if let Some(clients) = clients.upgrade(){
if let Some(sock)=clients.write().await.get_mut(&addr){
sock.last_msg_time = UNIX_EPOCH.elapsed().unwrap().as_secs();
}
}
}
_ = dis_rx.recv() =>{
from_self_rx.close();
cleanup(clients,&addr,dis_client_tx).await;
break
}
_ = tokio::time::sleep(Duration::from_secs(30)) ,if client_timeout>0 =>{
if let Some(clients) = clients.upgrade(){
let clients = clients.read().await;
if let Some(sock)=clients.get(&addr){
if UNIX_EPOCH.elapsed().unwrap().as_secs() - sock.last_msg_time>=client_timeout as u64{
let _ = sock.disconnect_notifier_main_tx.send(()).await;
}
}
}else{
break;
}
}
}
}
});
}
} else {
let _ = notx.send("Socket Closed".into());
break;
}
}
});
}
async fn cleanup(clients: WeakClientMap, addr: &SocketAddr, notifier: Sender<()>) {
if let Some(clients) = clients.upgrade() {
if let Some(sock) = clients.write().await.remove(addr) {
let _ = sock.disconnect_notifier_main_tx.send(()).await;
let _ = notifier.send_timeout((), Duration::from_secs(5)).await;
}
}
}