1 files changed, 142 insertions, 0 deletions
diff --git a/src/backend/libc/event/poll_fd.rs b/src/backend/libc/event/poll_fd.rs
new file mode 100644
index 0000000..32fd83d
--- /dev/null
+++ b/src/backend/libc/event/poll_fd.rs
@@ -0,0 +1,142 @@
+use crate::backend::c;
+use crate::backend::conv::borrowed_fd;
+use crate::backend::fd::{AsFd, AsRawFd, BorrowedFd, LibcFd};
+use bitflags::bitflags;
+use core::marker::PhantomData;
+#[cfg(windows)]
+use {
+    crate::backend::fd::{AsSocket, RawFd},
+    core::fmt,
+};
+
+bitflags! {
+    /// `POLL*` flags for use with [`poll`].
+    ///
+    /// [`poll`]: crate::event::poll
+    #[repr(transparent)]
+    #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+    pub struct PollFlags: c::c_short {
+        /// `POLLIN`
+        const IN = c::POLLIN;
+        /// `POLLPRI`
+        #[cfg(not(target_os = "wasi"))]
+        const PRI = c::POLLPRI;
+        /// `POLLOUT`
+        const OUT = c::POLLOUT;
+        /// `POLLRDNORM`
+        const RDNORM = c::POLLRDNORM;
+        /// `POLLWRNORM`
+        #[cfg(not(target_os = "l4re"))]
+        const WRNORM = c::POLLWRNORM;
+        /// `POLLRDBAND`
+        #[cfg(not(any(target_os = "l4re", target_os = "wasi")))]
+        const RDBAND = c::POLLRDBAND;
+        /// `POLLWRBAND`
+        #[cfg(not(any(target_os = "l4re", target_os = "wasi")))]
+        const WRBAND = c::POLLWRBAND;
+        /// `POLLERR`
+        const ERR = c::POLLERR;
+        /// `POLLHUP`
+        const HUP = c::POLLHUP;
+        /// `POLLNVAL`
+        #[cfg(not(target_os = "espidf"))]
+        const NVAL = c::POLLNVAL;
+        /// `POLLRDHUP`
+        #[cfg(all(
+            linux_kernel,
+            not(any(target_arch = "sparc", target_arch = "sparc64"))),
+        )]
+        const RDHUP = c::POLLRDHUP;
+
+        /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
+        const _ = !0;
+    }
+}
+
+/// `struct pollfd`—File descriptor and flags for use with [`poll`].
+///
+/// [`poll`]: crate::event::poll
+#[doc(alias = "pollfd")]
+#[derive(Clone)]
+#[cfg_attr(not(windows), derive(Debug))]
+#[repr(transparent)]
+pub struct PollFd<'fd> {
+    pollfd: c::pollfd,
+    _phantom: PhantomData<BorrowedFd<'fd>>,
+}
+
+#[cfg(windows)]
+impl<'fd> fmt::Debug for PollFd<'fd> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_struct("pollfd")
+            .field("fd", &self.pollfd.fd)
+            .field("events", &self.pollfd.events)
+            .field("revents", &self.pollfd.revents)
+            .finish()
+    }
+}
+
+impl<'fd> PollFd<'fd> {
+    /// Constructs a new `PollFd` holding `fd` and `events`.
+    #[inline]
+    pub fn new<Fd: AsFd>(fd: &'fd Fd, events: PollFlags) -> Self {
+        Self::from_borrowed_fd(fd.as_fd(), events)
+    }
+
+    /// Sets the contained file descriptor to `fd`.
+    #[inline]
+    pub fn set_fd<Fd: AsFd>(&mut self, fd: &'fd Fd) {
+        self.pollfd.fd = fd.as_fd().as_raw_fd() as LibcFd;
+    }
+
+    /// Clears the ready events.
+    #[inline]
+    pub fn clear_revents(&mut self) {
+        self.pollfd.revents = 0;
+    }
+
+    /// Constructs a new `PollFd` holding `fd` and `events`.
+    ///
+    /// This is the same as `new`, but can be used to avoid borrowing the
+    /// `BorrowedFd`, which can be tricky in situations where the `BorrowedFd`
+    /// is a temporary.
+    #[inline]
+    pub fn from_borrowed_fd(fd: BorrowedFd<'fd>, events: PollFlags) -> Self {
+        Self {
+            pollfd: c::pollfd {
+                fd: borrowed_fd(fd),
+                events: events.bits(),
+                revents: 0,
+            },
+            _phantom: PhantomData,
+        }
+    }
+
+    /// Returns the ready events.
+    #[inline]
+    pub fn revents(&self) -> PollFlags {
+        // Use `.unwrap()` here because in theory we know we know all the bits
+        // the OS might set here, but OS's have added extensions in the past.
+        PollFlags::from_bits(self.pollfd.revents).unwrap()
+    }
+}
+
+#[cfg(not(windows))]
+impl<'fd> AsFd for PollFd<'fd> {
+    #[inline]
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        // SAFETY: Our constructors and `set_fd` require `pollfd.fd` to be
+        // valid for the `'fd` lifetime.
+        unsafe { BorrowedFd::borrow_raw(self.pollfd.fd) }
+    }
+}
+
+#[cfg(windows)]
+impl<'fd> AsSocket for PollFd<'fd> {
+    #[inline]
+    fn as_socket(&self) -> BorrowedFd<'_> {
+        // SAFETY: Our constructors and `set_fd` require `pollfd.fd` to be
+        // valid for the `'fd` lifetime.
+        unsafe { BorrowedFd::borrow_raw(self.pollfd.fd as RawFd) }
+    }
+}