1 files changed, 93 insertions, 0 deletions
diff --git a/third_party/rust/devd-rs/src/lib.rs b/third_party/rust/devd-rs/src/lib.rs
new file mode 100644
index 0000000000..8c863e856e
--- /dev/null
+++ b/third_party/rust/devd-rs/src/lib.rs
@@ -0,0 +1,93 @@
+pub mod data;
+pub mod parser;
+pub mod result;
+
+use io::{BufRead, BufReader};
+use libc::{c_int, connect, nfds_t, poll, pollfd, sockaddr_un, socket, AF_UNIX, POLLIN, SOCK_SEQPACKET};
+use std::cmp::Ordering;
+use std::os::unix::io::{FromRawFd, RawFd};
+use std::os::unix::net::UnixStream;
+use std::{io, mem, ptr};
+
+pub use data::*;
+pub use result::*;
+
+const SOCKET_PATH: &str = "/var/run/devd.seqpacket.pipe";
+
+pub fn parse_devd_event(event: &str) -> Result<Event> {
+    match parser::event(event) {
+        Ok((_, x)) => Ok(x),
+        _ => Err(Error::Parse),
+    }
+}
+
+#[derive(Debug)]
+pub struct Context {
+    sock: BufReader<UnixStream>,
+    sockfd: RawFd,
+    buffer: String,
+}
+
+impl Context {
+    pub fn new() -> Result<Context> {
+        unsafe {
+            let sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
+            if sockfd < 0 {
+                return Err(io::Error::last_os_error().into());
+            }
+            let mut sockaddr = sockaddr_un { sun_family: AF_UNIX as _, ..mem::zeroed() };
+            ptr::copy_nonoverlapping(SOCKET_PATH.as_ptr(), sockaddr.sun_path.as_mut_ptr() as *mut u8, SOCKET_PATH.len());
+            if connect(
+                sockfd,
+                &sockaddr as *const sockaddr_un as *const _,
+                (mem::size_of_val(&AF_UNIX) + SOCKET_PATH.len()) as _,
+            ) < 0
+            {
+                return Err(io::Error::last_os_error().into());
+            }
+            Ok(Context {
+                sock: BufReader::new(UnixStream::from_raw_fd(sockfd)),
+                sockfd,
+                buffer: String::new(),
+            })
+        }
+    }
+
+    pub fn wait_for_event_raw_internal(&mut self, timeout_ms: usize) -> Result<&str> {
+        let mut fds = [pollfd { fd: self.sockfd, events: POLLIN, revents: 0 }];
+        let x = unsafe { poll((&mut fds).as_mut_ptr(), fds.len() as nfds_t, timeout_ms as c_int) };
+
+        match x.cmp(&0) {
+            Ordering::Less => Err(io::Error::last_os_error().into()),
+            Ordering::Equal => Err(Error::Timeout),
+            Ordering::Greater => {
+                self.buffer.clear();
+                self.sock.read_line(&mut self.buffer)?;
+                Ok(&self.buffer)
+            }
+        }
+    }
+
+    /// Waits for an event using poll(), reads it but does not parse
+    pub fn wait_for_event_raw(&mut self, timeout_ms: usize) -> Result<String> {
+        self.wait_for_event_raw_internal(timeout_ms).map(ToOwned::to_owned)
+    }
+
+    /// Waits for an event using poll(), reads and parses it
+    pub fn wait_for_event(&mut self, timeout_ms: usize) -> Result<Event> {
+        self.wait_for_event_raw_internal(timeout_ms).and_then(parse_devd_event)
+    }
+
+    /// Returns the devd socket file descriptor in case you want to select/poll on it together with
+    /// other file descriptors
+    pub fn fd(&self) -> RawFd {
+        self.sockfd
+    }
+
+    /// Reads an event and parses it. Use when polling on the raw fd by yourself
+    pub fn read_event(&mut self) -> Result<Event> {
+        self.buffer.clear();
+        self.sock.read_line(&mut self.buffer)?;
+        parse_devd_event(&self.buffer)
+    }
+}