1use std::{
2 ops::Deref,
3 os::unix::io::{
4 AsFd,
5 AsRawFd,
6 BorrowedFd,
7 FromRawFd,
8 IntoRawFd,
9 RawFd,
10 },
11 sync::atomic::{
12 AtomicBool,
13 Ordering,
14 },
15};
16
17use inotify_sys as ffi;
18
19
20/// A RAII guard around a `RawFd` that closes it automatically on drop.
21#[derive(Debug)]
22pub struct FdGuard {
23 pub(crate) fd : RawFd,
24 pub(crate) close_on_drop: AtomicBool,
25}
26
27impl FdGuard {
28
29 /// Indicate that the wrapped file descriptor should _not_ be closed
30 /// when the guard is dropped.
31 ///
32 /// This should be called in cases where ownership of the wrapped file
33 /// descriptor has been "moved" out of the guard.
34 ///
35 /// This is factored out into a separate function to ensure that it's
36 /// always used consistently.
37 #[inline]
38 pub fn should_not_close(&self) {
39 self.close_on_drop.store(val:false, order:Ordering::Release);
40 }
41}
42
43impl Deref for FdGuard {
44 type Target = RawFd;
45
46 #[inline]
47 fn deref(&self) -> &Self::Target {
48 &self.fd
49 }
50}
51
52impl Drop for FdGuard {
53 fn drop(&mut self) {
54 if self.close_on_drop.load(order:Ordering::Acquire) {
55 unsafe { ffi::close(self.fd); }
56 }
57 }
58}
59
60impl FromRawFd for FdGuard {
61 unsafe fn from_raw_fd(fd: RawFd) -> Self {
62 FdGuard {
63 fd,
64 close_on_drop: AtomicBool::new(true),
65 }
66 }
67}
68
69impl IntoRawFd for FdGuard {
70 fn into_raw_fd(self) -> RawFd {
71 self.should_not_close();
72 self.fd
73 }
74}
75
76impl AsRawFd for FdGuard {
77 fn as_raw_fd(&self) -> RawFd {
78 self.fd
79 }
80}
81
82impl AsFd for FdGuard {
83 #[inline]
84 fn as_fd(&self) -> BorrowedFd<'_> {
85 unsafe { BorrowedFd::borrow_raw(self.fd) }
86 }
87}
88
89impl PartialEq for FdGuard {
90 fn eq(&self, other: &FdGuard) -> bool {
91 self.fd == other.fd
92 }
93}
94