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
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
use crate::actor::{Actor, ActorHandle, ConnectionState};
use crate::client::ClientOperation;
use crate::dispatcher::MessageDispatcher;
use crate::message::peer::{
FileSearchResponse, GetShareFileList, PeerInit, PlaceInQueueRequest,
PlaceInQueueResponse, QueueUploadHandler, SharedDirectory,
SharedFileListResponseHandler, TransferRequest, TransferResponse,
UploadFailedHandler,
};
use crate::message::server::MessageFactory;
use crate::message::{Handlers, Message, MessageReader, MessageType};
use crate::peer::Peer;
use crate::types::{Download, SearchResult, Transfer};
use crate::utils::lock::RwLockExt;
use crate::{debug, error, trace, warn};
use std::io::{self, Error, Write};
use std::net::TcpStream;
use std::sync::mpsc::{Receiver, Sender};
use std::sync::{Arc, RwLock};
use std::time::{Duration, Instant};
#[derive(Debug, Clone)]
pub enum PeerMessage {
SendMessage(Message),
FileSearchResult(SearchResult),
TransferRequest(Transfer),
UploadFailed(String, String),
TransferResponse {
token: u32,
allowed: bool,
reason: Option<String>,
},
PlaceInQueueResponse {
filename: String,
place: u32,
},
SetUsername(String),
QueueUpload(String),
RequestTransfer(Download),
/// A peer queued one of our shared files for download (they sent us code 43).
IncomingQueueUpload(String),
/// A peer asked where their queued file sits (they sent us code 51).
IncomingPlaceInQueueRequest(String),
/// A peer asked to browse our shared files (they sent us code 4).
ShareListRequested,
/// A peer we are browsing sent us their shared-file listing (code 5).
ShareListReceived(Vec<SharedDirectory>),
/// Offer the queued file to that peer: send an upload TransferRequest.
ServeUpload {
token: u32,
filename: String,
size: u64,
},
ProcessRead,
}
pub struct PeerActor {
peer: Arc<RwLock<Peer>>,
stream: Option<TcpStream>,
connection_state: ConnectionState,
reader: MessageReader,
client_channel: Sender<ClientOperation>,
self_handle: Option<ActorHandle<PeerMessage>>,
dispatcher: Option<MessageDispatcher<PeerMessage>>,
dispatcher_receiver: Option<Receiver<PeerMessage>>,
queued_messages: Vec<PeerMessage>,
own_username: String,
/// True when we initiated this connection (no stream supplied at
/// construction), so we must send a `PeerInit` once connected.
outbound: bool,
/// Set once the connection is up. A pre-established failure on an outbound
/// connection means the peer is unreachable (likely firewalled).
established: bool,
/// Set once this actor has reported a terminal outcome (disconnect or
/// connect-failure). Guards against a second notification — e.g. when a
/// replaced actor is later stopped — which would otherwise alias and evict
/// a newer actor registered under the same username.
disconnect_reported: bool,
/// Registry-assigned unique id, echoed in terminal notifications so the
/// client evicts only this actor and never a newer namesake.
id: u64,
/// Transfer tokens for uploads we are serving to this peer. A TransferResponse
/// for one of these is our upload being accepted, not a download offer.
serving_tokens: std::collections::HashSet<u32>,
/// Bytes queued for the peer that the socket would not take yet. The stream
/// is non-blocking (so socket reads never starve the mailbox), so a message
/// larger than the send buffer — a full share listing is easily megabytes —
/// only partly fits; the rest drains on later ticks.
pending_write: Vec<u8>,
}
/// Cap on queued outbound bytes. A peer that stops reading must not be able to
/// grow this without bound; dropping that connection is the right answer.
const MAX_PENDING_WRITE: usize = 32 * 1024 * 1024;
impl PeerActor {
#[must_use]
pub fn new(
peer: Peer,
stream: Option<TcpStream>,
reader: Option<MessageReader>,
client_channel: Sender<ClientOperation>,
own_username: String,
id: u64,
) -> Self {
let outbound = stream.is_none();
let connection_state = if stream.is_some() {
ConnectionState::Connected
} else {
ConnectionState::Disconnected
};
Self {
peer: Arc::new(RwLock::new(peer)),
stream,
connection_state,
reader: reader.unwrap_or_default(),
client_channel,
self_handle: None,
dispatcher: None,
dispatcher_receiver: None,
queued_messages: Vec::new(),
own_username,
outbound,
established: false,
disconnect_reported: false,
id,
serving_tokens: std::collections::HashSet::new(),
pending_write: Vec::new(),
}
}
pub fn set_self_handle(&mut self, handle: ActorHandle<PeerMessage>) {
self.self_handle = Some(handle);
}
fn peer_username(&self) -> String {
match self.peer.read_safe() {
Ok(p) => p.username.clone(),
Err(e) => {
error!("[peer_actor] peer lock poisoned: {}", e);
"<unknown>".to_string()
}
}
}
fn peer_snapshot(&self) -> Option<Peer> {
match self.peer.read_safe() {
Ok(p) => Some(p.clone()),
Err(e) => {
error!("[peer_actor] peer lock poisoned: {}", e);
None
}
}
}
fn initialize_dispatcher(&mut self) {
let (dispatcher_sender, dispatcher_receiver) =
std::sync::mpsc::channel::<PeerMessage>();
self.dispatcher_receiver = Some(dispatcher_receiver);
let mut handlers = Handlers::new();
handlers.register_handler(FileSearchResponse);
handlers.register_handler(TransferRequest);
handlers.register_handler(TransferResponse);
handlers.register_handler(GetShareFileList);
handlers.register_handler(UploadFailedHandler);
handlers.register_handler(PlaceInQueueRequest);
handlers.register_handler(PlaceInQueueResponse);
handlers.register_handler(QueueUploadHandler);
handlers.register_handler(SharedFileListResponseHandler);
handlers.register_handler(PeerInit);
self.dispatcher = Some(MessageDispatcher::new(
"peer".to_string(),
dispatcher_sender,
handlers,
));
}
fn process_dispatcher_messages(&mut self) {
let messages: Vec<PeerMessage> = self
.dispatcher_receiver
.as_ref()
.map_or_else(Vec::new, |receiver| receiver.try_iter().collect());
for msg in &messages {
self.handle_message(msg.clone());
}
}
fn handle_message(&mut self, msg: PeerMessage) {
if matches!(self.connection_state, ConnectionState::Connecting { .. }) {
match &msg {
PeerMessage::SetUsername(_) | PeerMessage::ProcessRead => {}
_ => {
self.queued_messages.push(msg);
return;
}
}
}
match msg {
PeerMessage::SendMessage(message) => {
self.send_message(message);
}
PeerMessage::FileSearchResult(file_search) => {
self.handle_file_search_result(file_search);
}
PeerMessage::TransferRequest(transfer) => {
self.handle_transfer_request(transfer);
}
PeerMessage::TransferResponse {
token,
allowed,
reason,
} => {
self.handle_transfer_response(token, allowed, reason);
}
PeerMessage::PlaceInQueueResponse { filename, place } => {
self.handle_place_in_queue_response(filename, place);
}
PeerMessage::SetUsername(username) => {
self.handle_set_username(username);
}
PeerMessage::QueueUpload(filename) => {
let message =
MessageFactory::build_queue_upload_message(&filename);
self.send_message(message);
}
PeerMessage::IncomingQueueUpload(filename) => {
self.handle_incoming_queue_upload(filename);
}
PeerMessage::IncomingPlaceInQueueRequest(filename) => {
let requester_key = self.peer_username();
if let Err(e) = self.client_channel.send(
ClientOperation::PlaceInQueueRequested {
requester_key,
filename,
},
) {
error!(
"[peer_actor] forward IncomingPlaceInQueueRequest: {}",
e
);
}
}
PeerMessage::ServeUpload {
token,
filename,
size,
} => {
self.handle_serve_upload(token, filename, size);
}
PeerMessage::ShareListRequested => {
self.handle_share_list_requested();
}
PeerMessage::ShareListReceived(directories) => {
self.handle_share_list_received(directories);
}
PeerMessage::RequestTransfer(download) => {
let message = MessageFactory::build_transfer_request_message(
&download.filename,
download.token,
);
self.send_message(message);
}
PeerMessage::ProcessRead => {
self.process_read();
}
PeerMessage::UploadFailed(username, filename) => {
self.handle_upload_failed(username, filename);
}
}
}
fn handle_file_search_result(&self, file_search: SearchResult) {
if let Err(e) = self
.client_channel
.send(ClientOperation::SearchResult(file_search))
{
error!(
"[peer:{}] failed to forward search result: {}",
self.peer_username(),
e
);
}
}
/// A peer offers us a file. Record the peer's transfer token with the
/// client, and let *that* step send the TransferResponse.
///
/// The response is what invites the peer's file connection, and that
/// connection is matched by the peer's token — so replying here would race
/// the client loop that records the token. Under load the client loop is
/// the one that loses, the file connection finds no download, and the
/// transfer is dropped with the download stuck on Queued forever.
fn handle_transfer_request(&self, transfer: Transfer) {
let username = self.peer_username();
debug!("[peer:{}] TransferRequest for {}", username, transfer.token);
if let Err(e) =
self.client_channel
.send(ClientOperation::UpdateDownloadTokens(
transfer,
username.clone(),
))
{
error!(
"[peer:{}] failed to send UpdateDownloadTokens: {}",
username, e
);
}
}
fn handle_transfer_response(
&mut self,
token: u32,
allowed: bool,
reason: Option<String>,
) {
let username = self.peer_username();
debug!(
"[peer:{}] transfer response token: {} allowed: {}",
username, token, allowed
);
// If this token is one of our uploads, the peer just accepted
// our offer — start streaming. This leaves the download path
// (every other token) byte-for-byte unchanged.
if self.serving_tokens.remove(&token) {
if allowed {
let _ = self
.client_channel
.send(ClientOperation::StartUpload { token });
}
return;
}
if allowed {
debug!(
"[peer:{}] Transfer allowed, ready to connect with token {:}",
username, token
);
let Some(peer_snapshot) = self.peer_snapshot() else {
return;
};
if let Err(e) =
self.client_channel.send(ClientOperation::DownloadFromPeer(
token,
peer_snapshot,
allowed,
))
{
error!(
"[peer:{}] failed to send DownloadFromPeer: {}",
username, e
);
}
} else if let Some(reason_text) = reason {
debug!(
"[peer:{}] Transfer rejected: {} - token {}, waiting for TransferRequest...",
username, reason_text, token
);
}
}
fn handle_place_in_queue_response(&self, filename: String, place: u32) {
let username = self.peer_username();
debug!(
"[peer:{}] Place in queue response - file: {}, place: {}",
username, filename, place
);
if let Err(e) =
self.client_channel
.send(ClientOperation::PlaceInQueueUpdate {
username: username.clone(),
filename,
place,
})
{
error!(
"[peer:{}] failed to forward PlaceInQueueUpdate: {}",
username, e
);
}
}
fn handle_set_username(&self, username: String) {
trace!("[peer:{}] SetUsername: {}", self.peer_username(), username);
match self.peer.write_safe() {
Ok(mut p) => p.username = username,
Err(e) => {
error!("[peer_actor] SetUsername write: {}", e);
}
}
}
fn handle_incoming_queue_upload(&self, filename: String) {
// A peer wants to download one of our shared files. Ask the
// client (which owns the shares) to prepare the upload.
let requester_key = self.peer_username();
if let Err(e) = self.client_channel.send(ClientOperation::QueueUpload {
requester_key,
filename,
}) {
error!("[peer_actor] forward IncomingQueueUpload: {}", e);
}
}
fn handle_serve_upload(&mut self, token: u32, filename: String, size: u64) {
self.serving_tokens.insert(token);
let message = MessageFactory::build_upload_transfer_request(
&filename, token, size,
);
self.send_message(message);
}
fn handle_share_list_requested(&self) {
let requester_key = self.peer_username();
if let Err(e) = self
.client_channel
.send(ClientOperation::ShareListRequested { requester_key })
{
error!("[peer_actor] forward ShareListRequested: {}", e);
}
}
fn handle_share_list_received(&self, directories: Vec<SharedDirectory>) {
let username = self.peer_username();
if let Err(e) =
self.client_channel.send(ClientOperation::BrowseResult {
username,
directories,
})
{
error!("[peer_actor] forward BrowseResult: {}", e);
}
}
fn handle_upload_failed(&self, username: String, filename: String) {
if let Err(e) = self
.client_channel
.send(ClientOperation::UploadFailed(username, filename))
{
error!("[peer_actor] failed to forward UploadFailed: {}", e);
}
}
fn process_read(&mut self) {
if self.reader.buffer_len() > 0 {
self.extract_and_process_messages();
}
{
let Some(stream) = self.stream.as_mut() else {
return;
};
match self.reader.read_from_socket(stream) {
Ok(()) => {}
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {}
Err(ref e) if e.kind() == io::ErrorKind::TimedOut => {
if let Ok(peer_lock) = self.peer.read_safe() {
debug!(
"Read operation timed out for peer actor {:}:{:}",
peer_lock.host, peer_lock.port
);
}
}
// A peer hanging up a control connection it had already
// established is ordinary: other clients close idle peer
// sockets while a transfer runs on its own connection. Report
// the clean disconnect it is — an error here fails every
// download queued with that peer, the one streaming included.
// A connection that never established is the other story: the
// peer accepted and vanished, which is what the server-brokered
// fallback exists for, so that one keeps the error path.
Err(ref e)
if e.kind() == io::ErrorKind::UnexpectedEof
&& self.established =>
{
debug!(
"[peer:{}] peer closed the connection",
self.peer_username()
);
self.disconnect();
return;
}
Err(e) => {
let username = self.peer_username();
error!(
"[peer:{}] Error reading from peer: {} (kind: {:?}). Disconnecting.",
username,
e,
e.kind()
);
self.disconnect_with_error(e);
return;
}
}
}
self.extract_and_process_messages();
}
fn extract_and_process_messages(&mut self) {
let username = self.peer_username();
let mut extracted_count = 0;
loop {
match self.reader.extract_message() {
Ok(Some(mut message)) => {
extracted_count += 1;
trace!(
"[peer:{}] ← Message #{}: {:?}",
username,
extracted_count,
message
.get_message_name(
MessageType::Peer,
u32::from(message.get_message_code())
)
.map_err(|e| e.to_string())
);
if let Some(ref dispatcher) = self.dispatcher {
dispatcher.dispatch(&mut message);
} else {
warn!("[peer:{}] No dispatcher available!", username);
}
}
Err(e) => {
warn!(
"[peer:{}] Error extracting message: {}. Disconnecting peer.",
username, e
);
self.disconnect_with_error(e);
return;
}
Ok(None) => {
break;
}
}
}
self.process_dispatcher_messages();
}
fn send_message(&mut self, message: Message) {
let username = self.peer_username();
if self.stream.is_none() {
error!("Cannot send message: stream is None");
return;
}
trace!(
"[peer:{}] ➡ {:?}",
username,
message
.get_message_name(
MessageType::Peer,
u32::from_le_bytes(
message.get_slice(0, 4).try_into().unwrap_or_default()
)
)
.map_err(|e| e.to_string())
);
// Queue then drain, so messages always leave in order even when an
// earlier one is still partly buffered.
self.pending_write.extend_from_slice(&message.get_buffer());
self.flush_pending_write();
}
/// Push as much of `pending_write` into the socket as it will take. A
/// non-blocking socket refuses the rest with `WouldBlock`; that is normal
/// backpressure, not a failure, so the remainder stays queued for the next
/// tick. Only a real I/O error disconnects.
fn flush_pending_write(&mut self) {
if self.pending_write.is_empty() {
return;
}
let username = self.peer_username();
let Some(stream) = self.stream.as_mut() else {
return;
};
let mut written = 0;
let outcome = loop {
match stream.write(&self.pending_write[written..]) {
Ok(0) => {
break Err(Error::new(
io::ErrorKind::WriteZero,
"peer stopped accepting data",
));
}
Ok(n) => {
written += n;
if written == self.pending_write.len() {
break Ok(());
}
}
Err(ref e) if e.kind() == io::ErrorKind::Interrupted => {}
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
break Ok(());
}
Err(e) => break Err(e),
}
};
self.pending_write.drain(..written);
if let Err(e) = outcome {
error!(
"[peer:{}] Error writing message: {}. Disconnecting.",
username, e
);
self.disconnect_with_error(e);
return;
}
// Backpressure is normal, but what a peer has still not taken after we
// pushed everything we could is a peer that is not reading at all.
if self.pending_write.len() > MAX_PENDING_WRITE {
error!(
"[peer:{}] Outbound queue stuck above {} bytes. Disconnecting.",
username, MAX_PENDING_WRITE
);
self.disconnect_with_error(Error::new(
io::ErrorKind::WriteZero,
"peer is not draining our outbound queue",
));
}
}
fn disconnect_with_error(&mut self, error: Error) {
let username = self.peer_username();
// Include the cause: a failed outbound dial reports nothing else, so
// without it an unreachable peer is indistinguishable from a clean
// disconnect in the logs.
debug!("[peer:{}] disconnect: {}", username, error);
self.stream.take();
if self.disconnect_reported {
return;
}
self.disconnect_reported = true;
// A direct outbound connection that never established means the peer is
// unreachable (likely firewalled): signal a connect failure so the
// client can fall back to server-brokered connect. Anything else is a
// normal disconnect.
let op = if self.outbound && !self.established {
ClientOperation::PeerConnectFailed(self.id, username)
} else {
ClientOperation::PeerDisconnected(
self.id,
username,
Some(error.into()),
)
};
if let Err(e) = self.client_channel.send(op) {
error!("Failed to send disconnect notification: {}", e);
}
}
fn disconnect(&mut self) {
let username = self.peer_username();
debug!("[peer:{}] disconnect", username);
self.stream.take();
if self.disconnect_reported {
return;
}
self.disconnect_reported = true;
if let Err(e) = self
.client_channel
.send(ClientOperation::PeerDisconnected(self.id, username, None))
{
error!("Failed to send disconnect notification: {}", e);
}
}
fn initiate_connection(&mut self) {
let (username, host, port) = match self.peer.read_safe() {
Ok(peer) => (peer.username.clone(), peer.host.clone(), peer.port),
Err(e) => {
error!("[peer_actor] initiate_connection peer lock: {}", e);
return;
}
};
let socket_addr =
format!("{host}:{port}").parse::<std::net::SocketAddr>();
let addr = match socket_addr {
Ok(addr) => addr,
Err(e) => {
error!(
"[peer:{}] Invalid socket address {}:{} - {}",
username, host, port, e
);
self.disconnect_with_error(io::Error::new(
io::ErrorKind::InvalidInput,
e,
));
return;
}
};
// Use connect_timeout to prevent blocking the thread for too long
let timeout = Duration::from_secs(5);
let stream = match TcpStream::connect_timeout(&addr, timeout) {
Ok(stream) => stream,
Err(e) => {
self.disconnect_with_error(e);
return;
}
};
if let Err(e) = stream.set_nonblocking(true) {
error!("[peer:{}] Failed to set non-blocking: {}", username, e);
self.disconnect_with_error(e);
return;
}
stream.set_nodelay(true).ok();
self.stream = Some(stream);
self.connection_state = ConnectionState::Connecting {
since: Instant::now(),
};
}
fn check_connection_status(&mut self) {
let ConnectionState::Connecting { since } = self.connection_state
else {
return;
};
let username = self.peer_username();
if since.elapsed() > Duration::from_secs(20) {
error!("[peer:{}] Connection timeout after 20 seconds", username);
self.disconnect_with_error(io::Error::new(
io::ErrorKind::TimedOut,
"Connection timeout",
));
return;
}
let Some(ref stream) = self.stream else {
return;
};
match stream.peer_addr() {
Ok(_) => {
self.connection_state = ConnectionState::Connected;
self.on_connection_established();
}
Err(ref e) if e.kind() == io::ErrorKind::NotConnected => {}
Err(e) => {
error!("[peer:{}] Connection failed: {}", username, e);
self.disconnect_with_error(e);
}
}
}
fn on_connection_established(&mut self) {
let (username, connection_type, token) = match self.peer.read_safe() {
Ok(peer) => (
peer.username.clone(),
peer.connection_type.clone(),
peer.token,
),
Err(e) => {
error!(
"[peer_actor] on_connection_established peer lock: {}",
e
);
return;
}
};
self.established = true;
let Some(ref mut stream) = self.stream else {
return;
};
// Connections we initiated must announce themselves; inbound peers
// already sent us theirs, so we stay silent for them. A direct dial
// (resolved via GetPeerAddress, token None) sends a PeerInit; a dial we
// make because the server asked us to (a brokered ConnectToPeer carries
// the server's token) must instead PierceFirewall with that token so
// the remote peer can correlate its own request. `get_buffer` prepends
// the length prefix the peer's MessageReader expects.
if self.outbound {
let handshake = match token {
Some(server_token) => {
MessageFactory::build_pierce_firewall_message(server_token)
}
None => MessageFactory::build_peer_init_message(
&self.own_username,
connection_type,
0,
),
};
if let Err(e) = stream.write_all(&handshake.get_buffer()) {
error!(
"[peer:{}] Failed to send outbound handshake: {}",
username, e
);
self.disconnect_with_error(e);
return;
}
}
self.initialize_dispatcher();
let queued = std::mem::take(&mut self.queued_messages);
for msg in queued {
self.handle_message(msg);
}
// Tell the client the control connection is live so any downloads
// queued for this peer can now be requested over a handshaken stream.
if self.outbound {
let _ = self
.client_channel
.send(ClientOperation::PeerConnected(username));
}
if let Some(ref handle) = self.self_handle {
handle.send(PeerMessage::ProcessRead).ok();
}
self.process_read();
}
}
impl Actor for PeerActor {
type Message = PeerMessage;
fn handle(&mut self, msg: Self::Message) {
self.handle_message(msg);
}
fn on_start(&mut self) {
if self.stream.is_none() {
self.initiate_connection();
} else {
self.connection_state = ConnectionState::Connected;
self.on_connection_established();
}
}
fn on_stop(&mut self) {
let username = self.peer_username();
trace!("[peer:{}] actor stopping", username);
self.disconnect();
}
fn tick(&mut self) {
match self.connection_state {
ConnectionState::Connecting { .. } => {
self.check_connection_status();
}
ConnectionState::Connected => {
if self.stream.is_some() {
// a backlogged message drains one socket buffer
// per 100ms tick. Enough for a share listing; if a future
// message stream needs more throughput, wake the actor as
// soon as the socket is writable instead of on the tick.
self.flush_pending_write();
self.process_read();
self.flush_pending_write();
}
}
ConnectionState::Disconnected => {}
}
}
}