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1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
4 //
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
10
11 use fmt;
12 use io::{self, Error, ErrorKind};
13 use net::{ToSocketAddrs, SocketAddr, Ipv4Addr, Ipv6Addr};
14 use sys_common::net as net_imp;
15 use sys_common::{AsInner, FromInner, IntoInner};
16 use time::Duration;
17
18 /// A User Datagram Protocol socket.
19 ///
20 /// This is an implementation of a bound UDP socket. This supports both IPv4 and
21 /// IPv6 addresses, and there is no corresponding notion of a server because UDP
22 /// is a datagram protocol.
23 ///
24 /// # Examples
25 ///
26 /// ```no_run
27 /// use std::net::UdpSocket;
28 ///
29 /// # fn foo() -> std::io::Result<()> {
30 /// {
31 /// let mut socket = try!(UdpSocket::bind("127.0.0.1:34254"));
32 ///
33 /// // read from the socket
34 /// let mut buf = [0; 10];
35 /// let (amt, src) = try!(socket.recv_from(&mut buf));
36 ///
37 /// // send a reply to the socket we received data from
38 /// let buf = &mut buf[..amt];
39 /// buf.reverse();
40 /// try!(socket.send_to(buf, &src));
41 /// # Ok(())
42 /// } // the socket is closed here
43 /// # }
44 /// ```
45 #[stable(feature = "rust1", since = "1.0.0")]
46 pub struct UdpSocket(net_imp::UdpSocket);
47
48 impl UdpSocket {
49 /// Creates a UDP socket from the given address.
50 ///
51 /// The address type can be any implementor of `ToSocketAddr` trait. See
52 /// its documentation for concrete examples.
53 #[stable(feature = "rust1", since = "1.0.0")]
54 pub fn bind<A: ToSocketAddrs>(addr: A) -> io::Result<UdpSocket> {
55 super::each_addr(addr, net_imp::UdpSocket::bind).map(UdpSocket)
56 }
57
58 /// Receives data from the socket. On success, returns the number of bytes
59 /// read and the address from whence the data came.
60 #[stable(feature = "rust1", since = "1.0.0")]
61 pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
62 self.0.recv_from(buf)
63 }
64
65 /// Sends data on the socket to the given address. On success, returns the
66 /// number of bytes written.
67 ///
68 /// Address type can be any implementor of `ToSocketAddrs` trait. See its
69 /// documentation for concrete examples.
70 #[stable(feature = "rust1", since = "1.0.0")]
71 pub fn send_to<A: ToSocketAddrs>(&self, buf: &[u8], addr: A)
72 -> io::Result<usize> {
73 match addr.to_socket_addrs()?.next() {
74 Some(addr) => self.0.send_to(buf, &addr),
75 None => Err(Error::new(ErrorKind::InvalidInput,
76 "no addresses to send data to")),
77 }
78 }
79
80 /// Returns the socket address that this socket was created from.
81 #[stable(feature = "rust1", since = "1.0.0")]
82 pub fn local_addr(&self) -> io::Result<SocketAddr> {
83 self.0.socket_addr()
84 }
85
86 /// Creates a new independently owned handle to the underlying socket.
87 ///
88 /// The returned `UdpSocket` is a reference to the same socket that this
89 /// object references. Both handles will read and write the same port, and
90 /// options set on one socket will be propagated to the other.
91 #[stable(feature = "rust1", since = "1.0.0")]
92 pub fn try_clone(&self) -> io::Result<UdpSocket> {
93 self.0.duplicate().map(UdpSocket)
94 }
95
96 /// Sets the read timeout to the timeout specified.
97 ///
98 /// If the value specified is `None`, then `read` calls will block
99 /// indefinitely. It is an error to pass the zero `Duration` to this
100 /// method.
101 ///
102 /// # Note
103 ///
104 /// Platforms may return a different error code whenever a read times out as
105 /// a result of setting this option. For example Unix typically returns an
106 /// error of the kind `WouldBlock`, but Windows may return `TimedOut`.
107 #[stable(feature = "socket_timeout", since = "1.4.0")]
108 pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
109 self.0.set_read_timeout(dur)
110 }
111
112 /// Sets the write timeout to the timeout specified.
113 ///
114 /// If the value specified is `None`, then `write` calls will block
115 /// indefinitely. It is an error to pass the zero `Duration` to this
116 /// method.
117 ///
118 /// # Note
119 ///
120 /// Platforms may return a different error code whenever a write times out
121 /// as a result of setting this option. For example Unix typically returns
122 /// an error of the kind `WouldBlock`, but Windows may return `TimedOut`.
123 #[stable(feature = "socket_timeout", since = "1.4.0")]
124 pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
125 self.0.set_write_timeout(dur)
126 }
127
128 /// Returns the read timeout of this socket.
129 ///
130 /// If the timeout is `None`, then `read` calls will block indefinitely.
131 #[stable(feature = "socket_timeout", since = "1.4.0")]
132 pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
133 self.0.read_timeout()
134 }
135
136 /// Returns the write timeout of this socket.
137 ///
138 /// If the timeout is `None`, then `write` calls will block indefinitely.
139 #[stable(feature = "socket_timeout", since = "1.4.0")]
140 pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
141 self.0.write_timeout()
142 }
143
144 /// Sets the value of the `SO_BROADCAST` option for this socket.
145 ///
146 /// When enabled, this socket is allowed to send packets to a broadcast
147 /// address.
148 #[stable(feature = "net2_mutators", since = "1.9.0")]
149 pub fn set_broadcast(&self, broadcast: bool) -> io::Result<()> {
150 self.0.set_broadcast(broadcast)
151 }
152
153 /// Gets the value of the `SO_BROADCAST` option for this socket.
154 ///
155 /// For more information about this option, see
156 /// [`set_broadcast`][link].
157 ///
158 /// [link]: #method.set_broadcast
159 #[stable(feature = "net2_mutators", since = "1.9.0")]
160 pub fn broadcast(&self) -> io::Result<bool> {
161 self.0.broadcast()
162 }
163
164 /// Sets the value of the `IP_MULTICAST_LOOP` option for this socket.
165 ///
166 /// If enabled, multicast packets will be looped back to the local socket.
167 /// Note that this may not have any affect on IPv6 sockets.
168 #[stable(feature = "net2_mutators", since = "1.9.0")]
169 pub fn set_multicast_loop_v4(&self, multicast_loop_v4: bool) -> io::Result<()> {
170 self.0.set_multicast_loop_v4(multicast_loop_v4)
171 }
172
173 /// Gets the value of the `IP_MULTICAST_LOOP` option for this socket.
174 ///
175 /// For more information about this option, see
176 /// [`set_multicast_loop_v4`][link].
177 ///
178 /// [link]: #method.set_multicast_loop_v4
179 #[stable(feature = "net2_mutators", since = "1.9.0")]
180 pub fn multicast_loop_v4(&self) -> io::Result<bool> {
181 self.0.multicast_loop_v4()
182 }
183
184 /// Sets the value of the `IP_MULTICAST_TTL` option for this socket.
185 ///
186 /// Indicates the time-to-live value of outgoing multicast packets for
187 /// this socket. The default value is 1 which means that multicast packets
188 /// don't leave the local network unless explicitly requested.
189 ///
190 /// Note that this may not have any affect on IPv6 sockets.
191 #[stable(feature = "net2_mutators", since = "1.9.0")]
192 pub fn set_multicast_ttl_v4(&self, multicast_ttl_v4: u32) -> io::Result<()> {
193 self.0.set_multicast_ttl_v4(multicast_ttl_v4)
194 }
195
196 /// Gets the value of the `IP_MULTICAST_TTL` option for this socket.
197 ///
198 /// For more information about this option, see
199 /// [`set_multicast_ttl_v4`][link].
200 ///
201 /// [link]: #method.set_multicast_ttl_v4
202 #[stable(feature = "net2_mutators", since = "1.9.0")]
203 pub fn multicast_ttl_v4(&self) -> io::Result<u32> {
204 self.0.multicast_ttl_v4()
205 }
206
207 /// Sets the value of the `IPV6_MULTICAST_LOOP` option for this socket.
208 ///
209 /// Controls whether this socket sees the multicast packets it sends itself.
210 /// Note that this may not have any affect on IPv4 sockets.
211 #[stable(feature = "net2_mutators", since = "1.9.0")]
212 pub fn set_multicast_loop_v6(&self, multicast_loop_v6: bool) -> io::Result<()> {
213 self.0.set_multicast_loop_v6(multicast_loop_v6)
214 }
215
216 /// Gets the value of the `IPV6_MULTICAST_LOOP` option for this socket.
217 ///
218 /// For more information about this option, see
219 /// [`set_multicast_loop_v6`][link].
220 ///
221 /// [link]: #method.set_multicast_loop_v6
222 #[stable(feature = "net2_mutators", since = "1.9.0")]
223 pub fn multicast_loop_v6(&self) -> io::Result<bool> {
224 self.0.multicast_loop_v6()
225 }
226
227 /// Sets the value for the `IP_TTL` option on this socket.
228 ///
229 /// This value sets the time-to-live field that is used in every packet sent
230 /// from this socket.
231 #[stable(feature = "net2_mutators", since = "1.9.0")]
232 pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
233 self.0.set_ttl(ttl)
234 }
235
236 /// Gets the value of the `IP_TTL` option for this socket.
237 ///
238 /// For more information about this option, see [`set_ttl`][link].
239 ///
240 /// [link]: #method.set_ttl
241 #[stable(feature = "net2_mutators", since = "1.9.0")]
242 pub fn ttl(&self) -> io::Result<u32> {
243 self.0.ttl()
244 }
245
246 /// Executes an operation of the `IP_ADD_MEMBERSHIP` type.
247 ///
248 /// This function specifies a new multicast group for this socket to join.
249 /// The address must be a valid multicast address, and `interface` is the
250 /// address of the local interface with which the system should join the
251 /// multicast group. If it's equal to `INADDR_ANY` then an appropriate
252 /// interface is chosen by the system.
253 #[stable(feature = "net2_mutators", since = "1.9.0")]
254 pub fn join_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> io::Result<()> {
255 self.0.join_multicast_v4(multiaddr, interface)
256 }
257
258 /// Executes an operation of the `IPV6_ADD_MEMBERSHIP` type.
259 ///
260 /// This function specifies a new multicast group for this socket to join.
261 /// The address must be a valid multicast address, and `interface` is the
262 /// index of the interface to join/leave (or 0 to indicate any interface).
263 #[stable(feature = "net2_mutators", since = "1.9.0")]
264 pub fn join_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32) -> io::Result<()> {
265 self.0.join_multicast_v6(multiaddr, interface)
266 }
267
268 /// Executes an operation of the `IP_DROP_MEMBERSHIP` type.
269 ///
270 /// For more information about this option, see
271 /// [`join_multicast_v4`][link].
272 ///
273 /// [link]: #method.join_multicast_v4
274 #[stable(feature = "net2_mutators", since = "1.9.0")]
275 pub fn leave_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> io::Result<()> {
276 self.0.leave_multicast_v4(multiaddr, interface)
277 }
278
279 /// Executes an operation of the `IPV6_DROP_MEMBERSHIP` type.
280 ///
281 /// For more information about this option, see
282 /// [`join_multicast_v6`][link].
283 ///
284 /// [link]: #method.join_multicast_v6
285 #[stable(feature = "net2_mutators", since = "1.9.0")]
286 pub fn leave_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32) -> io::Result<()> {
287 self.0.leave_multicast_v6(multiaddr, interface)
288 }
289
290 /// Get the value of the `SO_ERROR` option on this socket.
291 ///
292 /// This will retrieve the stored error in the underlying socket, clearing
293 /// the field in the process. This can be useful for checking errors between
294 /// calls.
295 #[stable(feature = "net2_mutators", since = "1.9.0")]
296 pub fn take_error(&self) -> io::Result<Option<io::Error>> {
297 self.0.take_error()
298 }
299
300 /// Connects this UDP socket to a remote address, allowing the `send` and
301 /// `recv` syscalls to be used to send data and also applies filters to only
302 /// receive data from the specified address.
303 #[stable(feature = "net2_mutators", since = "1.9.0")]
304 pub fn connect<A: ToSocketAddrs>(&self, addr: A) -> io::Result<()> {
305 super::each_addr(addr, |addr| self.0.connect(addr))
306 }
307
308 /// Sends data on the socket to the remote address to which it is connected.
309 ///
310 /// The `connect` method will connect this socket to a remote address. This
311 /// method will fail if the socket is not connected.
312 #[stable(feature = "net2_mutators", since = "1.9.0")]
313 pub fn send(&self, buf: &[u8]) -> io::Result<usize> {
314 self.0.send(buf)
315 }
316
317 /// Receives data on the socket from the remote address to which it is
318 /// connected.
319 ///
320 /// The `connect` method will connect this socket to a remote address. This
321 /// method will fail if the socket is not connected.
322 #[stable(feature = "net2_mutators", since = "1.9.0")]
323 pub fn recv(&self, buf: &mut [u8]) -> io::Result<usize> {
324 self.0.recv(buf)
325 }
326
327 /// Moves this TCP stream into or out of nonblocking mode.
328 ///
329 /// On Unix this corresponds to calling fcntl, and on Windows this
330 /// corresponds to calling ioctlsocket.
331 #[stable(feature = "net2_mutators", since = "1.9.0")]
332 pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
333 self.0.set_nonblocking(nonblocking)
334 }
335 }
336
337 impl AsInner<net_imp::UdpSocket> for UdpSocket {
338 fn as_inner(&self) -> &net_imp::UdpSocket { &self.0 }
339 }
340
341 impl FromInner<net_imp::UdpSocket> for UdpSocket {
342 fn from_inner(inner: net_imp::UdpSocket) -> UdpSocket { UdpSocket(inner) }
343 }
344
345 impl IntoInner<net_imp::UdpSocket> for UdpSocket {
346 fn into_inner(self) -> net_imp::UdpSocket { self.0 }
347 }
348
349 #[stable(feature = "rust1", since = "1.0.0")]
350 impl fmt::Debug for UdpSocket {
351 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
352 self.0.fmt(f)
353 }
354 }
355
356 #[cfg(test)]
357 mod tests {
358 use prelude::v1::*;
359
360 use io::ErrorKind;
361 use net::*;
362 use net::test::{next_test_ip4, next_test_ip6};
363 use sync::mpsc::channel;
364 use sys_common::AsInner;
365 use time::{Instant, Duration};
366 use thread;
367
368 fn each_ip(f: &mut FnMut(SocketAddr, SocketAddr)) {
369 f(next_test_ip4(), next_test_ip4());
370 f(next_test_ip6(), next_test_ip6());
371 }
372
373 macro_rules! t {
374 ($e:expr) => {
375 match $e {
376 Ok(t) => t,
377 Err(e) => panic!("received error for `{}`: {}", stringify!($e), e),
378 }
379 }
380 }
381
382 #[test]
383 fn bind_error() {
384 match UdpSocket::bind("1.1.1.1:9999") {
385 Ok(..) => panic!(),
386 Err(e) => {
387 assert_eq!(e.kind(), ErrorKind::AddrNotAvailable)
388 }
389 }
390 }
391
392 #[test]
393 fn socket_smoke_test_ip4() {
394 each_ip(&mut |server_ip, client_ip| {
395 let (tx1, rx1) = channel();
396 let (tx2, rx2) = channel();
397
398 let _t = thread::spawn(move|| {
399 let client = t!(UdpSocket::bind(&client_ip));
400 rx1.recv().unwrap();
401 t!(client.send_to(&[99], &server_ip));
402 tx2.send(()).unwrap();
403 });
404
405 let server = t!(UdpSocket::bind(&server_ip));
406 tx1.send(()).unwrap();
407 let mut buf = [0];
408 let (nread, src) = t!(server.recv_from(&mut buf));
409 assert_eq!(nread, 1);
410 assert_eq!(buf[0], 99);
411 assert_eq!(src, client_ip);
412 rx2.recv().unwrap();
413 })
414 }
415
416 #[test]
417 fn socket_name_ip4() {
418 each_ip(&mut |addr, _| {
419 let server = t!(UdpSocket::bind(&addr));
420 assert_eq!(addr, t!(server.local_addr()));
421 })
422 }
423
424 #[test]
425 fn udp_clone_smoke() {
426 each_ip(&mut |addr1, addr2| {
427 let sock1 = t!(UdpSocket::bind(&addr1));
428 let sock2 = t!(UdpSocket::bind(&addr2));
429
430 let _t = thread::spawn(move|| {
431 let mut buf = [0, 0];
432 assert_eq!(sock2.recv_from(&mut buf).unwrap(), (1, addr1));
433 assert_eq!(buf[0], 1);
434 t!(sock2.send_to(&[2], &addr1));
435 });
436
437 let sock3 = t!(sock1.try_clone());
438
439 let (tx1, rx1) = channel();
440 let (tx2, rx2) = channel();
441 let _t = thread::spawn(move|| {
442 rx1.recv().unwrap();
443 t!(sock3.send_to(&[1], &addr2));
444 tx2.send(()).unwrap();
445 });
446 tx1.send(()).unwrap();
447 let mut buf = [0, 0];
448 assert_eq!(sock1.recv_from(&mut buf).unwrap(), (1, addr2));
449 rx2.recv().unwrap();
450 })
451 }
452
453 #[test]
454 fn udp_clone_two_read() {
455 each_ip(&mut |addr1, addr2| {
456 let sock1 = t!(UdpSocket::bind(&addr1));
457 let sock2 = t!(UdpSocket::bind(&addr2));
458 let (tx1, rx) = channel();
459 let tx2 = tx1.clone();
460
461 let _t = thread::spawn(move|| {
462 t!(sock2.send_to(&[1], &addr1));
463 rx.recv().unwrap();
464 t!(sock2.send_to(&[2], &addr1));
465 rx.recv().unwrap();
466 });
467
468 let sock3 = t!(sock1.try_clone());
469
470 let (done, rx) = channel();
471 let _t = thread::spawn(move|| {
472 let mut buf = [0, 0];
473 t!(sock3.recv_from(&mut buf));
474 tx2.send(()).unwrap();
475 done.send(()).unwrap();
476 });
477 let mut buf = [0, 0];
478 t!(sock1.recv_from(&mut buf));
479 tx1.send(()).unwrap();
480
481 rx.recv().unwrap();
482 })
483 }
484
485 #[test]
486 fn udp_clone_two_write() {
487 each_ip(&mut |addr1, addr2| {
488 let sock1 = t!(UdpSocket::bind(&addr1));
489 let sock2 = t!(UdpSocket::bind(&addr2));
490
491 let (tx, rx) = channel();
492 let (serv_tx, serv_rx) = channel();
493
494 let _t = thread::spawn(move|| {
495 let mut buf = [0, 1];
496 rx.recv().unwrap();
497 t!(sock2.recv_from(&mut buf));
498 serv_tx.send(()).unwrap();
499 });
500
501 let sock3 = t!(sock1.try_clone());
502
503 let (done, rx) = channel();
504 let tx2 = tx.clone();
505 let _t = thread::spawn(move|| {
506 match sock3.send_to(&[1], &addr2) {
507 Ok(..) => { let _ = tx2.send(()); }
508 Err(..) => {}
509 }
510 done.send(()).unwrap();
511 });
512 match sock1.send_to(&[2], &addr2) {
513 Ok(..) => { let _ = tx.send(()); }
514 Err(..) => {}
515 }
516 drop(tx);
517
518 rx.recv().unwrap();
519 serv_rx.recv().unwrap();
520 })
521 }
522
523 #[test]
524 fn debug() {
525 let name = if cfg!(windows) {"socket"} else {"fd"};
526 let socket_addr = next_test_ip4();
527
528 let udpsock = t!(UdpSocket::bind(&socket_addr));
529 let udpsock_inner = udpsock.0.socket().as_inner();
530 let compare = format!("UdpSocket {{ addr: {:?}, {}: {:?} }}",
531 socket_addr, name, udpsock_inner);
532 assert_eq!(format!("{:?}", udpsock), compare);
533 }
534
535 // FIXME: re-enabled bitrig/openbsd/netbsd tests once their socket timeout code
536 // no longer has rounding errors.
537 #[cfg_attr(any(target_os = "bitrig", target_os = "netbsd", target_os = "openbsd"), ignore)]
538 #[test]
539 fn timeouts() {
540 let addr = next_test_ip4();
541
542 let stream = t!(UdpSocket::bind(&addr));
543 let dur = Duration::new(15410, 0);
544
545 assert_eq!(None, t!(stream.read_timeout()));
546
547 t!(stream.set_read_timeout(Some(dur)));
548 assert_eq!(Some(dur), t!(stream.read_timeout()));
549
550 assert_eq!(None, t!(stream.write_timeout()));
551
552 t!(stream.set_write_timeout(Some(dur)));
553 assert_eq!(Some(dur), t!(stream.write_timeout()));
554
555 t!(stream.set_read_timeout(None));
556 assert_eq!(None, t!(stream.read_timeout()));
557
558 t!(stream.set_write_timeout(None));
559 assert_eq!(None, t!(stream.write_timeout()));
560 }
561
562 #[test]
563 fn test_read_timeout() {
564 let addr = next_test_ip4();
565
566 let stream = t!(UdpSocket::bind(&addr));
567 t!(stream.set_read_timeout(Some(Duration::from_millis(1000))));
568
569 let mut buf = [0; 10];
570
571 let start = Instant::now();
572 let kind = stream.recv_from(&mut buf).err().expect("expected error").kind();
573 assert!(kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut);
574 assert!(start.elapsed() > Duration::from_millis(400));
575 }
576
577 #[test]
578 fn test_read_with_timeout() {
579 let addr = next_test_ip4();
580
581 let stream = t!(UdpSocket::bind(&addr));
582 t!(stream.set_read_timeout(Some(Duration::from_millis(1000))));
583
584 t!(stream.send_to(b"hello world", &addr));
585
586 let mut buf = [0; 11];
587 t!(stream.recv_from(&mut buf));
588 assert_eq!(b"hello world", &buf[..]);
589
590 let start = Instant::now();
591 let kind = stream.recv_from(&mut buf).err().expect("expected error").kind();
592 assert!(kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut);
593 assert!(start.elapsed() > Duration::from_millis(400));
594 }
595
596 #[test]
597 fn connect_send_recv() {
598 let addr = next_test_ip4();
599
600 let socket = t!(UdpSocket::bind(&addr));
601 t!(socket.connect(addr));
602
603 t!(socket.send(b"hello world"));
604
605 let mut buf = [0; 11];
606 t!(socket.recv(&mut buf));
607 assert_eq!(b"hello world", &buf[..]);
608 }
609
610 #[test]
611 fn ttl() {
612 let ttl = 100;
613
614 let addr = next_test_ip4();
615
616 let stream = t!(UdpSocket::bind(&addr));
617
618 t!(stream.set_ttl(ttl));
619 assert_eq!(ttl, t!(stream.ttl()));
620 }
621
622 #[test]
623 fn set_nonblocking() {
624 let addr = next_test_ip4();
625
626 let stream = t!(UdpSocket::bind(&addr));
627
628 t!(stream.set_nonblocking(true));
629 t!(stream.set_nonblocking(false));
630 }
631 }