std/sys/pal/unix/linux/
pidfd.rs

1use crate::io;
2use crate::os::fd::{AsRawFd, FromRawFd, RawFd};
3use crate::sys::cvt;
4use crate::sys::fd::FileDesc;
5use crate::sys::process::ExitStatus;
6use crate::sys_common::{AsInner, FromInner, IntoInner};
7
8#[cfg(test)]
9mod tests;
10
11#[derive(Debug)]
12pub(crate) struct PidFd(FileDesc);
13
14impl PidFd {
15    pub fn kill(&self) -> io::Result<()> {
16        self.send_signal(libc::SIGKILL)
17    }
18
19    pub(crate) fn send_signal(&self, signal: i32) -> io::Result<()> {
20        cvt(unsafe {
21            libc::syscall(
22                libc::SYS_pidfd_send_signal,
23                self.0.as_raw_fd(),
24                signal,
25                crate::ptr::null::<()>(),
26                0,
27            )
28        })
29        .map(drop)
30    }
31
32    pub fn wait(&self) -> io::Result<ExitStatus> {
33        let mut siginfo: libc::siginfo_t = unsafe { crate::mem::zeroed() };
34        cvt(unsafe {
35            libc::waitid(libc::P_PIDFD, self.0.as_raw_fd() as u32, &mut siginfo, libc::WEXITED)
36        })?;
37        Ok(ExitStatus::from_waitid_siginfo(siginfo))
38    }
39
40    pub fn try_wait(&self) -> io::Result<Option<ExitStatus>> {
41        let mut siginfo: libc::siginfo_t = unsafe { crate::mem::zeroed() };
42
43        cvt(unsafe {
44            libc::waitid(
45                libc::P_PIDFD,
46                self.0.as_raw_fd() as u32,
47                &mut siginfo,
48                libc::WEXITED | libc::WNOHANG,
49            )
50        })?;
51        if unsafe { siginfo.si_pid() } == 0 {
52            Ok(None)
53        } else {
54            Ok(Some(ExitStatus::from_waitid_siginfo(siginfo)))
55        }
56    }
57}
58
59impl AsInner<FileDesc> for PidFd {
60    fn as_inner(&self) -> &FileDesc {
61        &self.0
62    }
63}
64
65impl IntoInner<FileDesc> for PidFd {
66    fn into_inner(self) -> FileDesc {
67        self.0
68    }
69}
70
71impl FromInner<FileDesc> for PidFd {
72    fn from_inner(inner: FileDesc) -> Self {
73        Self(inner)
74    }
75}
76
77impl FromRawFd for PidFd {
78    unsafe fn from_raw_fd(fd: RawFd) -> Self {
79        Self(FileDesc::from_raw_fd(fd))
80    }
81}