gdbstub/conn/impls/
unixstream.rs

1use crate::conn::Connection;
2use crate::conn::ConnectionExt;
3use std::io;
4use std::os::unix::net::UnixStream;
5
6// TODO: Remove PeekExt once rust-lang/rust#73761 is stabilized
7trait PeekExt {
8    fn peek(&self, buf: &mut [u8]) -> io::Result<usize>;
9}
10
11impl PeekExt for UnixStream {
12    #[cfg(feature = "paranoid_unsafe")]
13    #[allow(clippy::panic)]
14    fn peek(&self, _buf: &mut [u8]) -> io::Result<usize> {
15        panic!("cannot use `UnixStream::peek` with `paranoid_unsafe` until rust-lang/rust#73761 is stabilized");
16    }
17
18    #[cfg(not(feature = "paranoid_unsafe"))]
19    #[allow(non_camel_case_types)]
20    fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
21        use core::ffi::c_void;
22        use std::os::unix::io::AsRawFd;
23
24        // Define some libc types inline (to avoid bringing in entire libc dep)
25
26        // every platform supported by the libc crate uses c_int = i32
27        type c_int = i32;
28        type size_t = usize;
29        type ssize_t = isize;
30        const MSG_PEEK: c_int = 2;
31        extern "C" {
32            fn recv(socket: c_int, buf: *mut c_void, len: size_t, flags: c_int) -> ssize_t;
33        }
34
35        // from std/sys/unix/mod.rs
36        pub fn cvt(t: isize) -> io::Result<isize> {
37            if t == -1 {
38                Err(io::Error::last_os_error())
39            } else {
40                Ok(t)
41            }
42        }
43
44        // from std/sys/unix/net.rs
45        let ret = cvt(unsafe {
46            recv(
47                self.as_raw_fd(),
48                buf.as_mut_ptr() as *mut c_void,
49                buf.len(),
50                MSG_PEEK,
51            )
52        })?;
53        Ok(ret as usize)
54    }
55}
56
57impl Connection for UnixStream {
58    type Error = std::io::Error;
59
60    fn write(&mut self, byte: u8) -> Result<(), Self::Error> {
61        use std::io::Write;
62
63        Write::write_all(self, &[byte])
64    }
65
66    fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::Error> {
67        use std::io::Write;
68
69        Write::write_all(self, buf)
70    }
71
72    fn flush(&mut self) -> Result<(), Self::Error> {
73        use std::io::Write;
74
75        Write::flush(self)
76    }
77}
78
79impl ConnectionExt for UnixStream {
80    fn read(&mut self) -> Result<u8, Self::Error> {
81        use std::io::Read;
82
83        self.set_nonblocking(false)?;
84
85        let mut buf = [0u8];
86        match Read::read_exact(self, &mut buf) {
87            Ok(_) => Ok(buf[0]),
88            Err(e) => Err(e),
89        }
90    }
91
92    fn peek(&mut self) -> Result<Option<u8>, Self::Error> {
93        self.set_nonblocking(true)?;
94
95        let mut buf = [0u8];
96        match PeekExt::peek(self, &mut buf) {
97            Ok(_) => Ok(Some(buf[0])),
98            Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => Ok(None),
99            Err(e) => Err(e),
100        }
101    }
102}
gdbstub/conn/impls/unixstream.rs

gdbstub/conn/impls/
unixstream.rs
