1 files changed, 72 insertions, 5 deletions

diff --git a/third_party/rust/nix/src/sys/eventfd.rs b/third_party/rust/nix/src/sys/eventfd.rs
index f1723519cf..50a4f091bd 100644
--- a/third_party/rust/nix/src/sys/eventfd.rs
+++ b/third_party/rust/nix/src/sys/eventfd.rs
@@ -1,17 +1,84 @@
 use crate::errno::Errno;
-use crate::Result;
-use std::os::unix::io::{FromRawFd, OwnedFd};
+use crate::{Result,unistd};
+use std::os::unix::io::{FromRawFd, OwnedFd, AsRawFd, AsFd, RawFd, BorrowedFd};
 
 libc_bitflags! {
     pub struct EfdFlags: libc::c_int {
-        EFD_CLOEXEC; // Since Linux 2.6.27
-        EFD_NONBLOCK; // Since Linux 2.6.27
-        EFD_SEMAPHORE; // Since Linux 2.6.30
+        EFD_CLOEXEC; // Since Linux 2.6.27/FreeBSD 13.0
+        EFD_NONBLOCK; // Since Linux 2.6.27/FreeBSD 13.0
+        EFD_SEMAPHORE; // Since Linux 2.6.30/FreeBSD 13.0
     }
 }
 
+#[deprecated(since = "0.28.0", note = "Use EventFd::from_value_and_flags() instead")]
 pub fn eventfd(initval: libc::c_uint, flags: EfdFlags) -> Result<OwnedFd> {
     let res = unsafe { libc::eventfd(initval, flags.bits()) };
 
     Errno::result(res).map(|r| unsafe { OwnedFd::from_raw_fd(r) })
 }
+
+#[derive(Debug)]
+#[repr(transparent)]
+pub struct EventFd(OwnedFd);
+impl EventFd {
+    /// [`EventFd::from_value_and_flags`] with `init_val = 0` and `flags = EfdFlags::empty()`.
+    pub fn new() -> Result<Self> {
+        Self::from_value_and_flags(0, EfdFlags::empty())
+    }
+    /// Constructs [`EventFd`] with the given `init_val` and `flags`.
+    /// 
+    /// Wrapper around [`libc::eventfd`].
+    pub fn from_value_and_flags(init_val: u32, flags: EfdFlags) -> Result<Self> {
+        let res = unsafe { libc::eventfd(init_val, flags.bits()) };
+        Errno::result(res).map(|r| Self(unsafe { OwnedFd::from_raw_fd(r) }))
+    }
+    /// [`EventFd::from_value_and_flags`] with `init_val = 0` and given `flags`.
+    pub fn from_flags(flags: EfdFlags) -> Result<Self> {
+        Self::from_value_and_flags(0, flags)
+    }
+    /// [`EventFd::from_value_and_flags`] with given `init_val` and `flags = EfdFlags::empty()`.
+    pub fn from_value(init_val: u32) -> Result<Self> {
+        Self::from_value_and_flags(init_val, EfdFlags::empty())
+    }
+    /// Arms `self`, a following call to `poll`, `select` or `epoll` will return immediately.
+    /// 
+    /// [`EventFd::write`] with `1`.
+    pub fn arm(&self) -> Result<usize> {
+        self.write(1)
+    }
+    /// Defuses `self`, a following call to `poll`, `select` or `epoll` will block.
+    /// 
+    /// [`EventFd::write`] with `0`.
+    pub fn defuse(&self) -> Result<usize> {
+        self.write(0)
+    }
+    /// Enqueues `value` triggers.
+    /// 
+    /// The next `value` calls to `poll`, `select` or `epoll` will return immediately.
+    /// 
+    /// [`EventFd::write`] with `value`.
+    pub fn write(&self, value: u64) -> Result<usize> { 
+        unistd::write(&self.0,&value.to_ne_bytes())
+    }
+    // Reads the value from the file descriptor.
+    pub fn read(&self) -> Result<u64> {
+        let mut arr = [0; std::mem::size_of::<u64>()];
+        unistd::read(self.0.as_raw_fd(),&mut arr)?;
+        Ok(u64::from_ne_bytes(arr))
+    }
+}
+impl AsFd for EventFd {
+    fn as_fd(&self) -> BorrowedFd {
+        self.0.as_fd()
+    }
+}
+impl AsRawFd for EventFd {
+    fn as_raw_fd(&self) -> RawFd {
+        self.0.as_raw_fd()
+    }
+}
+impl From<EventFd> for OwnedFd {
+    fn from(x: EventFd) -> OwnedFd {
+        x.0
+    }
+}