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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962
use crate::future::poll_fn;
use crate::io::{AsyncRead, AsyncWrite, Interest, PollEvented, ReadBuf, Ready};
use crate::net::unix::split::{split, ReadHalf, WriteHalf};
use crate::net::unix::split_owned::{split_owned, OwnedReadHalf, OwnedWriteHalf};
use crate::net::unix::ucred::{self, UCred};
use crate::net::unix::SocketAddr;
use std::convert::TryFrom;
use std::fmt;
use std::io::{self, Read, Write};
use std::net::Shutdown;
use std::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
use std::os::unix::net;
use std::path::Path;
use std::pin::Pin;
use std::task::{Context, Poll};
cfg_io_util! {
use bytes::BufMut;
}
cfg_net_unix! {
/// A structure representing a connected Unix socket.
///
/// This socket can be connected directly with `UnixStream::connect` or accepted
/// from a listener with `UnixListener::incoming`. Additionally, a pair of
/// anonymous Unix sockets can be created with `UnixStream::pair`.
///
/// To shut down the stream in the write direction, you can call the
/// [`shutdown()`] method. This will cause the other peer to receive a read of
/// length 0, indicating that no more data will be sent. This only closes
/// the stream in one direction.
///
/// [`shutdown()`]: fn@crate::io::AsyncWriteExt::shutdown
pub struct UnixStream {
io: PollEvented<mio::net::UnixStream>,
}
}
impl UnixStream {
/// Connects to the socket named by `path`.
///
/// This function will create a new Unix socket and connect to the path
/// specified, associating the returned stream with the default event loop's
/// handle.
pub async fn connect<P>(path: P) -> io::Result<UnixStream>
where
P: AsRef<Path>,
{
let stream = mio::net::UnixStream::connect(path)?;
let stream = UnixStream::new(stream)?;
poll_fn(|cx| stream.io.registration().poll_write_ready(cx)).await?;
if let Some(e) = stream.io.take_error()? {
return Err(e);
}
Ok(stream)
}
/// Waits for any of the requested ready states.
///
/// This function is usually paired with `try_read()` or `try_write()`. It
/// can be used to concurrently read / write to the same socket on a single
/// task without splitting the socket.
///
/// # Cancel safety
///
/// This method is cancel safe. Once a readiness event occurs, the method
/// will continue to return immediately until the readiness event is
/// consumed by an attempt to read or write that fails with `WouldBlock` or
/// `Poll::Pending`.
///
/// # Examples
///
/// Concurrently read and write to the stream on the same task without
/// splitting.
///
/// ```no_run
/// use tokio::io::Interest;
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// loop {
/// let ready = stream.ready(Interest::READABLE | Interest::WRITABLE).await?;
///
/// if ready.is_readable() {
/// let mut data = vec![0; 1024];
/// // Try to read data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_read(&mut data) {
/// Ok(n) => {
/// println!("read {} bytes", n);
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
///
/// }
///
/// if ready.is_writable() {
/// // Try to write data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_write(b"hello world") {
/// Ok(n) => {
/// println!("write {} bytes", n);
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
/// }
/// }
/// ```
pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
let event = self.io.registration().readiness(interest).await?;
Ok(event.ready)
}
/// Waits for the socket to become readable.
///
/// This function is equivalent to `ready(Interest::READABLE)` and is usually
/// paired with `try_read()`.
///
/// # Cancel safety
///
/// This method is cancel safe. Once a readiness event occurs, the method
/// will continue to return immediately until the readiness event is
/// consumed by an attempt to read that fails with `WouldBlock` or
/// `Poll::Pending`.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// let mut msg = vec![0; 1024];
///
/// loop {
/// // Wait for the socket to be readable
/// stream.readable().await?;
///
/// // Try to read data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_read(&mut msg) {
/// Ok(n) => {
/// msg.truncate(n);
/// break;
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// println!("GOT = {:?}", msg);
/// Ok(())
/// }
/// ```
pub async fn readable(&self) -> io::Result<()> {
self.ready(Interest::READABLE).await?;
Ok(())
}
/// Polls for read readiness.
///
/// If the unix stream is not currently ready for reading, this method will
/// store a clone of the `Waker` from the provided `Context`. When the unix
/// stream becomes ready for reading, `Waker::wake` will be called on the
/// waker.
///
/// Note that on multiple calls to `poll_read_ready` or `poll_read`, only
/// the `Waker` from the `Context` passed to the most recent call is
/// scheduled to receive a wakeup. (However, `poll_write_ready` retains a
/// second, independent waker.)
///
/// This function is intended for cases where creating and pinning a future
/// via [`readable`] is not feasible. Where possible, using [`readable`] is
/// preferred, as this supports polling from multiple tasks at once.
///
/// # Return value
///
/// The function returns:
///
/// * `Poll::Pending` if the unix stream is not ready for reading.
/// * `Poll::Ready(Ok(()))` if the unix stream is ready for reading.
/// * `Poll::Ready(Err(e))` if an error is encountered.
///
/// # Errors
///
/// This function may encounter any standard I/O error except `WouldBlock`.
///
/// [`readable`]: method@Self::readable
pub fn poll_read_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
self.io.registration().poll_read_ready(cx).map_ok(|_| ())
}
/// Try to read data from the stream into the provided buffer, returning how
/// many bytes were read.
///
/// Receives any pending data from the socket but does not wait for new data
/// to arrive. On success, returns the number of bytes read. Because
/// `try_read()` is non-blocking, the buffer does not have to be stored by
/// the async task and can exist entirely on the stack.
///
/// Usually, [`readable()`] or [`ready()`] is used with this function.
///
/// [`readable()`]: UnixStream::readable()
/// [`ready()`]: UnixStream::ready()
///
/// # Return
///
/// If data is successfully read, `Ok(n)` is returned, where `n` is the
/// number of bytes read. `Ok(0)` indicates the stream's read half is closed
/// and will no longer yield data. If the stream is not ready to read data
/// `Err(io::ErrorKind::WouldBlock)` is returned.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// loop {
/// // Wait for the socket to be readable
/// stream.readable().await?;
///
/// // Creating the buffer **after** the `await` prevents it from
/// // being stored in the async task.
/// let mut buf = [0; 4096];
///
/// // Try to read data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_read(&mut buf) {
/// Ok(0) => break,
/// Ok(n) => {
/// println!("read {} bytes", n);
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// ```
pub fn try_read(&self, buf: &mut [u8]) -> io::Result<usize> {
self.io
.registration()
.try_io(Interest::READABLE, || (&*self.io).read(buf))
}
/// Tries to read data from the stream into the provided buffers, returning
/// how many bytes were read.
///
/// Data is copied to fill each buffer in order, with the final buffer
/// written to possibly being only partially filled. This method behaves
/// equivalently to a single call to [`try_read()`] with concatenated
/// buffers.
///
/// Receives any pending data from the socket but does not wait for new data
/// to arrive. On success, returns the number of bytes read. Because
/// `try_read_vectored()` is non-blocking, the buffer does not have to be
/// stored by the async task and can exist entirely on the stack.
///
/// Usually, [`readable()`] or [`ready()`] is used with this function.
///
/// [`try_read()`]: UnixStream::try_read()
/// [`readable()`]: UnixStream::readable()
/// [`ready()`]: UnixStream::ready()
///
/// # Return
///
/// If data is successfully read, `Ok(n)` is returned, where `n` is the
/// number of bytes read. `Ok(0)` indicates the stream's read half is closed
/// and will no longer yield data. If the stream is not ready to read data
/// `Err(io::ErrorKind::WouldBlock)` is returned.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io::{self, IoSliceMut};
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// loop {
/// // Wait for the socket to be readable
/// stream.readable().await?;
///
/// // Creating the buffer **after** the `await` prevents it from
/// // being stored in the async task.
/// let mut buf_a = [0; 512];
/// let mut buf_b = [0; 1024];
/// let mut bufs = [
/// IoSliceMut::new(&mut buf_a),
/// IoSliceMut::new(&mut buf_b),
/// ];
///
/// // Try to read data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_read_vectored(&mut bufs) {
/// Ok(0) => break,
/// Ok(n) => {
/// println!("read {} bytes", n);
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// ```
pub fn try_read_vectored(&self, bufs: &mut [io::IoSliceMut<'_>]) -> io::Result<usize> {
self.io
.registration()
.try_io(Interest::READABLE, || (&*self.io).read_vectored(bufs))
}
cfg_io_util! {
/// Tries to read data from the stream into the provided buffer, advancing the
/// buffer's internal cursor, returning how many bytes were read.
///
/// Receives any pending data from the socket but does not wait for new data
/// to arrive. On success, returns the number of bytes read. Because
/// `try_read_buf()` is non-blocking, the buffer does not have to be stored by
/// the async task and can exist entirely on the stack.
///
/// Usually, [`readable()`] or [`ready()`] is used with this function.
///
/// [`readable()`]: UnixStream::readable()
/// [`ready()`]: UnixStream::ready()
///
/// # Return
///
/// If data is successfully read, `Ok(n)` is returned, where `n` is the
/// number of bytes read. `Ok(0)` indicates the stream's read half is closed
/// and will no longer yield data. If the stream is not ready to read data
/// `Err(io::ErrorKind::WouldBlock)` is returned.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// loop {
/// // Wait for the socket to be readable
/// stream.readable().await?;
///
/// let mut buf = Vec::with_capacity(4096);
///
/// // Try to read data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_read_buf(&mut buf) {
/// Ok(0) => break,
/// Ok(n) => {
/// println!("read {} bytes", n);
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// ```
pub fn try_read_buf<B: BufMut>(&self, buf: &mut B) -> io::Result<usize> {
self.io.registration().try_io(Interest::READABLE, || {
use std::io::Read;
let dst = buf.chunk_mut();
let dst =
unsafe { &mut *(dst as *mut _ as *mut [std::mem::MaybeUninit<u8>] as *mut [u8]) };
// Safety: We trust `UnixStream::read` to have filled up `n` bytes in the
// buffer.
let n = (&*self.io).read(dst)?;
unsafe {
buf.advance_mut(n);
}
Ok(n)
})
}
}
/// Waits for the socket to become writable.
///
/// This function is equivalent to `ready(Interest::WRITABLE)` and is usually
/// paired with `try_write()`.
///
/// # Cancel safety
///
/// This method is cancel safe. Once a readiness event occurs, the method
/// will continue to return immediately until the readiness event is
/// consumed by an attempt to write that fails with `WouldBlock` or
/// `Poll::Pending`.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// loop {
/// // Wait for the socket to be writable
/// stream.writable().await?;
///
/// // Try to write data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_write(b"hello world") {
/// Ok(n) => {
/// break;
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// ```
pub async fn writable(&self) -> io::Result<()> {
self.ready(Interest::WRITABLE).await?;
Ok(())
}
/// Polls for write readiness.
///
/// If the unix stream is not currently ready for writing, this method will
/// store a clone of the `Waker` from the provided `Context`. When the unix
/// stream becomes ready for writing, `Waker::wake` will be called on the
/// waker.
///
/// Note that on multiple calls to `poll_write_ready` or `poll_write`, only
/// the `Waker` from the `Context` passed to the most recent call is
/// scheduled to receive a wakeup. (However, `poll_read_ready` retains a
/// second, independent waker.)
///
/// This function is intended for cases where creating and pinning a future
/// via [`writable`] is not feasible. Where possible, using [`writable`] is
/// preferred, as this supports polling from multiple tasks at once.
///
/// # Return value
///
/// The function returns:
///
/// * `Poll::Pending` if the unix stream is not ready for writing.
/// * `Poll::Ready(Ok(()))` if the unix stream is ready for writing.
/// * `Poll::Ready(Err(e))` if an error is encountered.
///
/// # Errors
///
/// This function may encounter any standard I/O error except `WouldBlock`.
///
/// [`writable`]: method@Self::writable
pub fn poll_write_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
self.io.registration().poll_write_ready(cx).map_ok(|_| ())
}
/// Tries to write a buffer to the stream, returning how many bytes were
/// written.
///
/// The function will attempt to write the entire contents of `buf`, but
/// only part of the buffer may be written.
///
/// This function is usually paired with `writable()`.
///
/// # Return
///
/// If data is successfully written, `Ok(n)` is returned, where `n` is the
/// number of bytes written. If the stream is not ready to write data,
/// `Err(io::ErrorKind::WouldBlock)` is returned.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// loop {
/// // Wait for the socket to be writable
/// stream.writable().await?;
///
/// // Try to write data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_write(b"hello world") {
/// Ok(n) => {
/// break;
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// ```
pub fn try_write(&self, buf: &[u8]) -> io::Result<usize> {
self.io
.registration()
.try_io(Interest::WRITABLE, || (&*self.io).write(buf))
}
/// Tries to write several buffers to the stream, returning how many bytes
/// were written.
///
/// Data is written from each buffer in order, with the final buffer read
/// from possible being only partially consumed. This method behaves
/// equivalently to a single call to [`try_write()`] with concatenated
/// buffers.
///
/// This function is usually paired with `writable()`.
///
/// [`try_write()`]: UnixStream::try_write()
///
/// # Return
///
/// If data is successfully written, `Ok(n)` is returned, where `n` is the
/// number of bytes written. If the stream is not ready to write data,
/// `Err(io::ErrorKind::WouldBlock)` is returned.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
/// use std::error::Error;
/// use std::io;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// // Connect to a peer
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// let bufs = [io::IoSlice::new(b"hello "), io::IoSlice::new(b"world")];
///
/// loop {
/// // Wait for the socket to be writable
/// stream.writable().await?;
///
/// // Try to write data, this may still fail with `WouldBlock`
/// // if the readiness event is a false positive.
/// match stream.try_write_vectored(&bufs) {
/// Ok(n) => {
/// break;
/// }
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// continue;
/// }
/// Err(e) => {
/// return Err(e.into());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// ```
pub fn try_write_vectored(&self, buf: &[io::IoSlice<'_>]) -> io::Result<usize> {
self.io
.registration()
.try_io(Interest::WRITABLE, || (&*self.io).write_vectored(buf))
}
/// Tries to read or write from the socket using a user-provided IO operation.
///
/// If the socket is ready, the provided closure is called. The closure
/// should attempt to perform IO operation from the socket by manually
/// calling the appropriate syscall. If the operation fails because the
/// socket is not actually ready, then the closure should return a
/// `WouldBlock` error and the readiness flag is cleared. The return value
/// of the closure is then returned by `try_io`.
///
/// If the socket is not ready, then the closure is not called
/// and a `WouldBlock` error is returned.
///
/// The closure should only return a `WouldBlock` error if it has performed
/// an IO operation on the socket that failed due to the socket not being
/// ready. Returning a `WouldBlock` error in any other situation will
/// incorrectly clear the readiness flag, which can cause the socket to
/// behave incorrectly.
///
/// The closure should not perform the IO operation using any of the methods
/// defined on the Tokio `UnixStream` type, as this will mess with the
/// readiness flag and can cause the socket to behave incorrectly.
///
/// Usually, [`readable()`], [`writable()`] or [`ready()`] is used with this function.
///
/// [`readable()`]: UnixStream::readable()
/// [`writable()`]: UnixStream::writable()
/// [`ready()`]: UnixStream::ready()
pub fn try_io<R>(
&self,
interest: Interest,
f: impl FnOnce() -> io::Result<R>,
) -> io::Result<R> {
self.io
.registration()
.try_io(interest, || self.io.try_io(f))
}
/// Creates new `UnixStream` from a `std::os::unix::net::UnixStream`.
///
/// This function is intended to be used to wrap a UnixStream from the
/// standard library in the Tokio equivalent. The conversion assumes
/// nothing about the underlying stream; it is left up to the user to set
/// it in non-blocking mode.
///
/// # Panics
///
/// This function panics if thread-local runtime is not set.
///
/// The runtime is usually set implicitly when this function is called
/// from a future driven by a tokio runtime, otherwise runtime can be set
/// explicitly with [`Runtime::enter`](crate::runtime::Runtime::enter) function.
pub fn from_std(stream: net::UnixStream) -> io::Result<UnixStream> {
let stream = mio::net::UnixStream::from_std(stream);
let io = PollEvented::new(stream)?;
Ok(UnixStream { io })
}
/// Turns a [`tokio::net::UnixStream`] into a [`std::os::unix::net::UnixStream`].
///
/// The returned [`std::os::unix::net::UnixStream`] will have nonblocking
/// mode set as `true`. Use [`set_nonblocking`] to change the blocking
/// mode if needed.
///
/// # Examples
///
/// ```
/// use std::error::Error;
/// use std::io::Read;
/// use tokio::net::UnixListener;
/// # use tokio::net::UnixStream;
/// # use tokio::io::AsyncWriteExt;
///
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
///
/// let mut data = [0u8; 12];
/// let listener = UnixListener::bind(&bind_path)?;
/// # let handle = tokio::spawn(async {
/// # let mut stream = UnixStream::connect(bind_path).await.unwrap();
/// # stream.write(b"Hello world!").await.unwrap();
/// # });
/// let (tokio_unix_stream, _) = listener.accept().await?;
/// let mut std_unix_stream = tokio_unix_stream.into_std()?;
/// # handle.await.expect("The task being joined has panicked");
/// std_unix_stream.set_nonblocking(false)?;
/// std_unix_stream.read_exact(&mut data)?;
/// # assert_eq!(b"Hello world!", &data);
/// Ok(())
/// }
/// ```
/// [`tokio::net::UnixStream`]: UnixStream
/// [`std::os::unix::net::UnixStream`]: std::os::unix::net::UnixStream
/// [`set_nonblocking`]: fn@std::os::unix::net::UnixStream::set_nonblocking
pub fn into_std(self) -> io::Result<std::os::unix::net::UnixStream> {
self.io
.into_inner()
.map(|io| io.into_raw_fd())
.map(|raw_fd| unsafe { std::os::unix::net::UnixStream::from_raw_fd(raw_fd) })
}
/// Creates an unnamed pair of connected sockets.
///
/// This function will create a pair of interconnected Unix sockets for
/// communicating back and forth between one another. Each socket will
/// be associated with the default event loop's handle.
pub fn pair() -> io::Result<(UnixStream, UnixStream)> {
let (a, b) = mio::net::UnixStream::pair()?;
let a = UnixStream::new(a)?;
let b = UnixStream::new(b)?;
Ok((a, b))
}
pub(crate) fn new(stream: mio::net::UnixStream) -> io::Result<UnixStream> {
let io = PollEvented::new(stream)?;
Ok(UnixStream { io })
}
/// Returns the socket address of the local half of this connection.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
///
/// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// println!("{:?}", stream.local_addr()?);
/// # Ok(())
/// # }
/// ```
pub fn local_addr(&self) -> io::Result<SocketAddr> {
self.io.local_addr().map(SocketAddr)
}
/// Returns the socket address of the remote half of this connection.
///
/// # Examples
///
/// ```no_run
/// use tokio::net::UnixStream;
///
/// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
/// let dir = tempfile::tempdir().unwrap();
/// let bind_path = dir.path().join("bind_path");
/// let stream = UnixStream::connect(bind_path).await?;
///
/// println!("{:?}", stream.peer_addr()?);
/// # Ok(())
/// # }
/// ```
pub fn peer_addr(&self) -> io::Result<SocketAddr> {
self.io.peer_addr().map(SocketAddr)
}
/// Returns effective credentials of the process which called `connect` or `pair`.
pub fn peer_cred(&self) -> io::Result<UCred> {
ucred::get_peer_cred(self)
}
/// Returns the value of the `SO_ERROR` option.
pub fn take_error(&self) -> io::Result<Option<io::Error>> {
self.io.take_error()
}
/// Shuts down the read, write, or both halves of this connection.
///
/// This function will cause all pending and future I/O calls on the
/// specified portions to immediately return with an appropriate value
/// (see the documentation of `Shutdown`).
pub(super) fn shutdown_std(&self, how: Shutdown) -> io::Result<()> {
self.io.shutdown(how)
}
// These lifetime markers also appear in the generated documentation, and make
// it more clear that this is a *borrowed* split.
#[allow(clippy::needless_lifetimes)]
/// Splits a `UnixStream` into a read half and a write half, which can be used
/// to read and write the stream concurrently.
///
/// This method is more efficient than [`into_split`], but the halves cannot be
/// moved into independently spawned tasks.
///
/// [`into_split`]: Self::into_split()
pub fn split<'a>(&'a mut self) -> (ReadHalf<'a>, WriteHalf<'a>) {
split(self)
}
/// Splits a `UnixStream` into a read half and a write half, which can be used
/// to read and write the stream concurrently.
///
/// Unlike [`split`], the owned halves can be moved to separate tasks, however
/// this comes at the cost of a heap allocation.
///
/// **Note:** Dropping the write half will shut down the write half of the
/// stream. This is equivalent to calling [`shutdown()`] on the `UnixStream`.
///
/// [`split`]: Self::split()
/// [`shutdown()`]: fn@crate::io::AsyncWriteExt::shutdown
pub fn into_split(self) -> (OwnedReadHalf, OwnedWriteHalf) {
split_owned(self)
}
}
impl TryFrom<net::UnixStream> for UnixStream {
type Error = io::Error;
/// Consumes stream, returning the tokio I/O object.
///
/// This is equivalent to
/// [`UnixStream::from_std(stream)`](UnixStream::from_std).
fn try_from(stream: net::UnixStream) -> io::Result<Self> {
Self::from_std(stream)
}
}
impl AsyncRead for UnixStream {
fn poll_read(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &mut ReadBuf<'_>,
) -> Poll<io::Result<()>> {
self.poll_read_priv(cx, buf)
}
}
impl AsyncWrite for UnixStream {
fn poll_write(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<io::Result<usize>> {
self.poll_write_priv(cx, buf)
}
fn poll_write_vectored(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
bufs: &[io::IoSlice<'_>],
) -> Poll<io::Result<usize>> {
self.poll_write_vectored_priv(cx, bufs)
}
fn is_write_vectored(&self) -> bool {
true
}
fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
Poll::Ready(Ok(()))
}
fn poll_shutdown(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
self.shutdown_std(std::net::Shutdown::Write)?;
Poll::Ready(Ok(()))
}
}
impl UnixStream {
// == Poll IO functions that takes `&self` ==
//
// To read or write without mutable access to the `UnixStream`, combine the
// `poll_read_ready` or `poll_write_ready` methods with the `try_read` or
// `try_write` methods.
pub(crate) fn poll_read_priv(
&self,
cx: &mut Context<'_>,
buf: &mut ReadBuf<'_>,
) -> Poll<io::Result<()>> {
// Safety: `UnixStream::read` correctly handles reads into uninitialized memory
unsafe { self.io.poll_read(cx, buf) }
}
pub(crate) fn poll_write_priv(
&self,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<io::Result<usize>> {
self.io.poll_write(cx, buf)
}
pub(super) fn poll_write_vectored_priv(
&self,
cx: &mut Context<'_>,
bufs: &[io::IoSlice<'_>],
) -> Poll<io::Result<usize>> {
self.io.poll_write_vectored(cx, bufs)
}
}
impl fmt::Debug for UnixStream {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.io.fmt(f)
}
}
impl AsRawFd for UnixStream {
fn as_raw_fd(&self) -> RawFd {
self.io.as_raw_fd()
}
}