src/libstd/sys/wasi/stdio.rs

   1 use crate::io::{self, IoSlice, IoSliceMut};
   2 use crate::mem::ManuallyDrop;
   3 use crate::sys::fd::WasiFd;
   4
   5 pub struct Stdin;
   6 pub struct Stdout;
   7 pub struct Stderr;
   8
   9 impl Stdin {
  10     pub fn new() -> io::Result<Stdin> {
  11         Ok(Stdin)
  12     }
  13
  14     #[inline]
  15     pub fn as_raw_fd(&self) -> u32 {
  16         0
  17     }
  18 }
  19
  20 impl io::Read for Stdin {
  21     fn read(&mut self, data: &mut [u8]) -> io::Result<usize> {
  22         self.read_vectored(&mut [IoSliceMut::new(data)])
  23     }
  24
  25     fn read_vectored(&mut self, data: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
  26         ManuallyDrop::new(unsafe { WasiFd::from_raw(self.as_raw_fd()) }).read(data)
  27     }
  28
  29     #[inline]
  30     fn is_read_vectored(&self) -> bool {
  31         true
  32     }
  33 }
  34
  35 impl Stdout {
  36     pub fn new() -> io::Result<Stdout> {
  37         Ok(Stdout)
  38     }
  39
  40     #[inline]
  41     pub fn as_raw_fd(&self) -> u32 {
  42         1
  43     }
  44 }
  45
  46 impl io::Write for Stdout {
  47     fn write(&mut self, data: &[u8]) -> io::Result<usize> {
  48         self.write_vectored(&[IoSlice::new(data)])
  49     }
  50
  51     fn write_vectored(&mut self, data: &[IoSlice<'_>]) -> io::Result<usize> {
  52         ManuallyDrop::new(unsafe { WasiFd::from_raw(self.as_raw_fd()) }).write(data)
  53     }
  54
  55     #[inline]
  56     fn is_write_vectored(&self) -> bool {
  57         true
  58     }
  59     fn flush(&mut self) -> io::Result<()> {
  60         Ok(())
  61     }
  62 }
  63
  64 impl Stderr {
  65     pub fn new() -> io::Result<Stderr> {
  66         Ok(Stderr)
  67     }
  68
  69     #[inline]
  70     pub fn as_raw_fd(&self) -> u32 {
  71         2
  72     }
  73 }
  74
  75 impl io::Write for Stderr {
  76     fn write(&mut self, data: &[u8]) -> io::Result<usize> {
  77         self.write_vectored(&[IoSlice::new(data)])
  78     }
  79
  80     fn write_vectored(&mut self, data: &[IoSlice<'_>]) -> io::Result<usize> {
  81         ManuallyDrop::new(unsafe { WasiFd::from_raw(self.as_raw_fd()) }).write(data)
  82     }
  83
  84     #[inline]
  85     fn is_write_vectored(&self) -> bool {
  86         true
  87     }
  88
  89     fn flush(&mut self) -> io::Result<()> {
  90         Ok(())
  91     }
  92 }
  93
  94 pub const STDIN_BUF_SIZE: usize = crate::sys_common::io::DEFAULT_BUF_SIZE;
  95
  96 pub fn is_ebadf(err: &io::Error) -> bool {
  97     err.raw_os_error() == Some(wasi::ERRNO_BADF.into())
  98 }
  99
 100 pub fn panic_output() -> Option<impl io::Write> {
 101     Stderr::new().ok()
 102 }