devd_rs/
lib.rs

1pub mod data;
2pub mod parser;
3pub mod result;
4
5use io::{BufRead, BufReader};
6use libc::{c_int, connect, nfds_t, poll, pollfd, sockaddr_un, socket, AF_UNIX, POLLIN, SOCK_SEQPACKET};
7use std::cmp::Ordering;
8use std::os::unix::io::{FromRawFd, RawFd};
9use std::os::unix::net::UnixStream;
10use std::{io, mem, ptr};
11
12pub use data::*;
13pub use result::*;
14
15const SOCKET_PATH: &str = "/var/run/devd.seqpacket.pipe";
16
17pub fn parse_devd_event(event: &str) -> Result<Event> {
18    match parser::event(event) {
19        Ok((_, x)) => Ok(x),
20        _ => Err(Error::Parse),
21    }
22}
23
24#[derive(Debug)]
25pub struct Context {
26    sock: BufReader<UnixStream>,
27    sockfd: RawFd,
28    buffer: String,
29}
30
31impl Context {
32    pub fn new() -> Result<Context> {
33        unsafe {
34            let sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
35            if sockfd < 0 {
36                return Err(io::Error::last_os_error().into());
37            }
38            let mut sockaddr = sockaddr_un { sun_family: AF_UNIX as _, ..mem::zeroed() };
39            ptr::copy_nonoverlapping(SOCKET_PATH.as_ptr(), sockaddr.sun_path.as_mut_ptr() as *mut u8, SOCKET_PATH.len());
40            if connect(
41                sockfd,
42                &sockaddr as *const sockaddr_un as *const _,
43                (mem::size_of_val(&AF_UNIX) + SOCKET_PATH.len()) as _,
44            ) < 0
45            {
46                return Err(io::Error::last_os_error().into());
47            }
48            Ok(Context {
49                sock: BufReader::new(UnixStream::from_raw_fd(sockfd)),
50                sockfd,
51                buffer: String::new(),
52            })
53        }
54    }
55
56    pub fn wait_for_event_raw_internal(&mut self, timeout_ms: usize) -> Result<&str> {
57        let mut fds = [pollfd { fd: self.sockfd, events: POLLIN, revents: 0 }];
58        let x = unsafe { poll((&mut fds).as_mut_ptr(), fds.len() as nfds_t, timeout_ms as c_int) };
59
60        match x.cmp(&0) {
61            Ordering::Less => Err(io::Error::last_os_error().into()),
62            Ordering::Equal => Err(Error::Timeout),
63            Ordering::Greater => {
64                self.buffer.clear();
65                self.sock.read_line(&mut self.buffer)?;
66                Ok(&self.buffer)
67            }
68        }
69    }
70
71    /// Waits for an event using poll(), reads it but does not parse
72    pub fn wait_for_event_raw(&mut self, timeout_ms: usize) -> Result<String> {
73        self.wait_for_event_raw_internal(timeout_ms).map(ToOwned::to_owned)
74    }
75
76    /// Waits for an event using poll(), reads and parses it
77    pub fn wait_for_event(&mut self, timeout_ms: usize) -> Result<Event> {
78        self.wait_for_event_raw_internal(timeout_ms).and_then(parse_devd_event)
79    }
80
81    /// Returns the devd socket file descriptor in case you want to select/poll on it together with
82    /// other file descriptors
83    pub fn fd(&self) -> RawFd {
84        self.sockfd
85    }
86
87    /// Reads an event and parses it. Use when polling on the raw fd by yourself
88    pub fn read_event(&mut self) -> Result<Event> {
89        self.buffer.clear();
90        self.sock.read_line(&mut self.buffer)?;
91        parse_devd_event(&self.buffer)
92    }
93}
devd_rs/lib.rs

devd_rs/
lib.rs
