1 | use crate::io::blocking::Blocking; |
2 | use crate::io::stdio_common::SplitByUtf8BoundaryIfWindows; |
3 | use crate::io::AsyncWrite; |
4 | use std::io; |
5 | use std::pin::Pin; |
6 | use std::task::Context; |
7 | use std::task::Poll; |
8 | |
9 | cfg_io_std! { |
10 | /// A handle to the standard output stream of a process. |
11 | /// |
12 | /// Concurrent writes to stdout must be executed with care: Only individual |
13 | /// writes to this [`AsyncWrite`] are guaranteed to be intact. In particular |
14 | /// you should be aware that writes using [`write_all`] are not guaranteed |
15 | /// to occur as a single write, so multiple threads writing data with |
16 | /// [`write_all`] may result in interleaved output. |
17 | /// |
18 | /// Created by the [`stdout`] function. |
19 | /// |
20 | /// [`stdout`]: stdout() |
21 | /// [`AsyncWrite`]: AsyncWrite |
22 | /// [`write_all`]: crate::io::AsyncWriteExt::write_all() |
23 | /// |
24 | /// # Examples |
25 | /// |
26 | /// ``` |
27 | /// use tokio::io::{self, AsyncWriteExt}; |
28 | /// |
29 | /// #[tokio::main] |
30 | /// async fn main() -> io::Result<()> { |
31 | /// let mut stdout = io::stdout(); |
32 | /// stdout.write_all(b"Hello world!").await?; |
33 | /// Ok(()) |
34 | /// } |
35 | /// ``` |
36 | #[derive(Debug)] |
37 | pub struct Stdout { |
38 | std: SplitByUtf8BoundaryIfWindows<Blocking<std::io::Stdout>>, |
39 | } |
40 | |
41 | /// Constructs a new handle to the standard output of the current process. |
42 | /// |
43 | /// The returned handle allows writing to standard out from the within the |
44 | /// Tokio runtime. |
45 | /// |
46 | /// Concurrent writes to stdout must be executed with care: Only individual |
47 | /// writes to this [`AsyncWrite`] are guaranteed to be intact. In particular |
48 | /// you should be aware that writes using [`write_all`] are not guaranteed |
49 | /// to occur as a single write, so multiple threads writing data with |
50 | /// [`write_all`] may result in interleaved output. |
51 | /// |
52 | /// [`AsyncWrite`]: AsyncWrite |
53 | /// [`write_all`]: crate::io::AsyncWriteExt::write_all() |
54 | /// |
55 | /// # Examples |
56 | /// |
57 | /// ``` |
58 | /// use tokio::io::{self, AsyncWriteExt}; |
59 | /// |
60 | /// #[tokio::main] |
61 | /// async fn main() -> io::Result<()> { |
62 | /// let mut stdout = io::stdout(); |
63 | /// stdout.write_all(b"Hello world!").await?; |
64 | /// Ok(()) |
65 | /// } |
66 | /// ``` |
67 | pub fn stdout() -> Stdout { |
68 | let std = io::stdout(); |
69 | Stdout { |
70 | std: SplitByUtf8BoundaryIfWindows::new(Blocking::new(std)), |
71 | } |
72 | } |
73 | } |
74 | |
75 | #[cfg (unix)] |
76 | mod sys { |
77 | use std::os::unix::io::{AsFd, AsRawFd, BorrowedFd, RawFd}; |
78 | |
79 | use super::Stdout; |
80 | |
81 | impl AsRawFd for Stdout { |
82 | fn as_raw_fd(&self) -> RawFd { |
83 | std::io::stdout().as_raw_fd() |
84 | } |
85 | } |
86 | |
87 | impl AsFd for Stdout { |
88 | fn as_fd(&self) -> BorrowedFd<'_> { |
89 | unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) } |
90 | } |
91 | } |
92 | } |
93 | |
94 | cfg_windows! { |
95 | use crate::os::windows::io::{AsHandle, BorrowedHandle, AsRawHandle, RawHandle}; |
96 | |
97 | impl AsRawHandle for Stdout { |
98 | fn as_raw_handle(&self) -> RawHandle { |
99 | std::io::stdout().as_raw_handle() |
100 | } |
101 | } |
102 | |
103 | impl AsHandle for Stdout { |
104 | fn as_handle(&self) -> BorrowedHandle<'_> { |
105 | unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) } |
106 | } |
107 | } |
108 | } |
109 | |
110 | impl AsyncWrite for Stdout { |
111 | fn poll_write( |
112 | mut self: Pin<&mut Self>, |
113 | cx: &mut Context<'_>, |
114 | buf: &[u8], |
115 | ) -> Poll<io::Result<usize>> { |
116 | Pin::new(&mut self.std).poll_write(cx, buf) |
117 | } |
118 | |
119 | fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), io::Error>> { |
120 | Pin::new(&mut self.std).poll_flush(cx) |
121 | } |
122 | |
123 | fn poll_shutdown( |
124 | mut self: Pin<&mut Self>, |
125 | cx: &mut Context<'_>, |
126 | ) -> Poll<Result<(), io::Error>> { |
127 | Pin::new(&mut self.std).poll_shutdown(cx) |
128 | } |
129 | } |
130 | |