std/sys/stdio/
unsupported.rs

1use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut};
2
3pub struct Stdin;
4pub struct Stdout;
5pub type Stderr = Stdout;
6
7impl Stdin {
8    pub const fn new() -> Stdin {
9        Stdin
10    }
11}
12
13impl io::Read for Stdin {
14    #[inline]
15    fn read(&mut self, _buf: &mut [u8]) -> io::Result<usize> {
16        Ok(0)
17    }
18
19    #[inline]
20    fn read_buf(&mut self, _cursor: BorrowedCursor<'_>) -> io::Result<()> {
21        Ok(())
22    }
23
24    #[inline]
25    fn read_vectored(&mut self, _bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
26        Ok(0)
27    }
28
29    #[inline]
30    fn is_read_vectored(&self) -> bool {
31        // Do not force `Chain<Empty, T>` or `Chain<T, Empty>` to use vectored
32        // reads, unless the other reader is vectored.
33        false
34    }
35
36    #[inline]
37    fn read_exact(&mut self, buf: &mut [u8]) -> io::Result<()> {
38        if !buf.is_empty() { Err(io::Error::READ_EXACT_EOF) } else { Ok(()) }
39    }
40
41    #[inline]
42    fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> io::Result<()> {
43        if cursor.capacity() != 0 { Err(io::Error::READ_EXACT_EOF) } else { Ok(()) }
44    }
45
46    #[inline]
47    fn read_to_end(&mut self, _buf: &mut Vec<u8>) -> io::Result<usize> {
48        Ok(0)
49    }
50
51    #[inline]
52    fn read_to_string(&mut self, _buf: &mut String) -> io::Result<usize> {
53        Ok(0)
54    }
55}
56
57impl Stdout {
58    pub const fn new() -> Stdout {
59        Stdout
60    }
61}
62
63impl io::Write for Stdout {
64    #[inline]
65    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
66        Ok(buf.len())
67    }
68
69    #[inline]
70    fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
71        let total_len = bufs.iter().map(|b| b.len()).sum();
72        Ok(total_len)
73    }
74
75    #[inline]
76    fn is_write_vectored(&self) -> bool {
77        true
78    }
79
80    #[inline]
81    fn write_all(&mut self, _buf: &[u8]) -> io::Result<()> {
82        Ok(())
83    }
84
85    #[inline]
86    fn write_all_vectored(&mut self, _bufs: &mut [IoSlice<'_>]) -> io::Result<()> {
87        Ok(())
88    }
89
90    // Keep the default write_fmt so the `fmt::Arguments` are still evaluated.
91
92    #[inline]
93    fn flush(&mut self) -> io::Result<()> {
94        Ok(())
95    }
96}
97
98pub const STDIN_BUF_SIZE: usize = 0;
99
100pub fn is_ebadf(_err: &io::Error) -> bool {
101    true
102}
103
104pub fn panic_output() -> Option<Vec<u8>> {
105    None
106}
std/sys/stdio/unsupported.rs

std/sys/stdio/
unsupported.rs
