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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/rustix/src/io/fd
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/rustix/src/io/fd')
-rw-r--r--vendor/rustix/src/io/fd/mod.rs17
-rw-r--r--vendor/rustix/src/io/fd/owned.rs252
-rw-r--r--vendor/rustix/src/io/fd/raw.rs159
3 files changed, 428 insertions, 0 deletions
diff --git a/vendor/rustix/src/io/fd/mod.rs b/vendor/rustix/src/io/fd/mod.rs
new file mode 100644
index 000000000..0978b5421
--- /dev/null
+++ b/vendor/rustix/src/io/fd/mod.rs
@@ -0,0 +1,17 @@
+//! The following is derived from Rust's
+//! library/std/src/os/fd/mod.rs at revision
+//! fa68e73e9947be8ffc5b3b46d899e4953a44e7e9.
+//!
+//! Owned and borrowed Unix-like file descriptors.
+
+#![cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+#![deny(unsafe_op_in_unsafe_fn)]
+
+// `RawFd`, `AsRawFd`, etc.
+mod raw;
+
+// `OwnedFd`, `AsFd`, etc.
+mod owned;
+
+pub use owned::*;
+pub use raw::*;
diff --git a/vendor/rustix/src/io/fd/owned.rs b/vendor/rustix/src/io/fd/owned.rs
new file mode 100644
index 000000000..d99b6a0f9
--- /dev/null
+++ b/vendor/rustix/src/io/fd/owned.rs
@@ -0,0 +1,252 @@
+//! The following is derived from Rust's
+//! library/std/src/os/fd/owned.rs at revision
+//! fa68e73e9947be8ffc5b3b46d899e4953a44e7e9.
+//!
+//! Owned and borrowed Unix-like file descriptors.
+
+#![cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+#![deny(unsafe_op_in_unsafe_fn)]
+#![allow(unsafe_code)]
+
+use super::raw::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
+use crate::io::close;
+use core::fmt;
+use core::marker::PhantomData;
+use core::mem::forget;
+
+/// A borrowed file descriptor.
+///
+/// This has a lifetime parameter to tie it to the lifetime of something that
+/// owns the file descriptor.
+///
+/// This uses `repr(transparent)` and has the representation of a host file
+/// descriptor, so it can be used in FFI in places where a file descriptor is
+/// passed as an argument, it is not captured or consumed, and it never has the
+/// value `-1`.
+///
+/// This type's `.to_owned()` implementation returns another `BorrowedFd`
+/// rather than an `OwnedFd`. It just makes a trivial copy of the raw file
+/// descriptor, which is then borrowed under the same lifetime.
+#[derive(Copy, Clone)]
+#[repr(transparent)]
+#[cfg_attr(rustc_attrs, rustc_layout_scalar_valid_range_start(0))]
+// libstd/os/raw/mod.rs assures me that every libstd-supported platform has a
+// 32-bit c_int. Below is -2, in two's complement, but that only works out
+// because c_int is 32 bits.
+#[cfg_attr(rustc_attrs, rustc_layout_scalar_valid_range_end(0xFF_FF_FF_FE))]
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+#[cfg_attr(rustc_attrs, rustc_nonnull_optimization_guaranteed)]
+pub struct BorrowedFd<'fd> {
+ fd: RawFd,
+ _phantom: PhantomData<&'fd OwnedFd>,
+}
+
+/// An owned file descriptor.
+///
+/// This closes the file descriptor on drop.
+///
+/// This uses `repr(transparent)` and has the representation of a host file
+/// descriptor, so it can be used in FFI in places where a file descriptor is
+/// passed as a consumed argument or returned as an owned value, and it never
+/// has the value `-1`.
+#[repr(transparent)]
+#[cfg_attr(rustc_attrs, rustc_layout_scalar_valid_range_start(0))]
+// libstd/os/raw/mod.rs assures me that every libstd-supported platform has a
+// 32-bit c_int. Below is -2, in two's complement, but that only works out
+// because c_int is 32 bits.
+#[cfg_attr(rustc_attrs, rustc_layout_scalar_valid_range_end(0xFF_FF_FF_FE))]
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+#[cfg_attr(rustc_attrs, rustc_nonnull_optimization_guaranteed)]
+pub struct OwnedFd {
+ fd: RawFd,
+}
+
+impl BorrowedFd<'_> {
+ /// Return a `BorrowedFd` holding the given raw file descriptor.
+ ///
+ /// # Safety
+ ///
+ /// The resource pointed to by `fd` must remain open for the duration of
+ /// the returned `BorrowedFd`, and it must not have the value `-1`.
+ #[inline]
+ #[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+ pub const unsafe fn borrow_raw(fd: RawFd) -> Self {
+ assert!(fd != u32::MAX as RawFd);
+ // SAFETY: we just asserted that the value is in the valid range and isn't `-1` (the only value bigger than `0xFF_FF_FF_FE` unsigned)
+ #[allow(unused_unsafe)]
+ unsafe {
+ Self {
+ fd,
+ _phantom: PhantomData,
+ }
+ }
+ }
+}
+
+impl OwnedFd {
+ /// Creates a new `OwnedFd` instance that shares the same underlying file handle
+ /// as the existing `OwnedFd` instance.
+ #[cfg(not(target_arch = "wasm32"))]
+ pub fn try_clone(&self) -> crate::io::Result<Self> {
+ // We want to atomically duplicate this file descriptor and set the
+ // CLOEXEC flag, and currently that's done via F_DUPFD_CLOEXEC. This
+ // is a POSIX flag that was added to Linux in 2.6.24.
+ #[cfg(not(target_os = "espidf"))]
+ let fd = crate::fs::fcntl_dupfd_cloexec(self, 0)?;
+
+ // For ESP-IDF, F_DUPFD is used instead, because the CLOEXEC semantics
+ // will never be supported, as this is a bare metal framework with
+ // no capabilities for multi-process execution. While F_DUPFD is also
+ // not supported yet, it might be (currently it returns ENOSYS).
+ #[cfg(target_os = "espidf")]
+ let fd = crate::fs::fcntl_dupfd(self)?;
+
+ Ok(fd.into())
+ }
+
+ #[cfg(target_arch = "wasm32")]
+ pub fn try_clone(&self) -> crate::io::Result<Self> {
+ Err(crate::io::const_io_error!(
+ crate::io::ErrorKind::Unsupported,
+ "operation not supported on WASI yet",
+ ))
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl AsRawFd for BorrowedFd<'_> {
+ #[inline]
+ fn as_raw_fd(&self) -> RawFd {
+ self.fd
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl AsRawFd for OwnedFd {
+ #[inline]
+ fn as_raw_fd(&self) -> RawFd {
+ self.fd
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl IntoRawFd for OwnedFd {
+ #[inline]
+ fn into_raw_fd(self) -> RawFd {
+ let fd = self.fd;
+ forget(self);
+ fd
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl FromRawFd for OwnedFd {
+ /// Constructs a new instance of `Self` from the given raw file descriptor.
+ ///
+ /// # Safety
+ ///
+ /// The resource pointed to by `fd` must be open and suitable for assuming
+ /// ownership. The resource must not require any cleanup other than `close`.
+ #[inline]
+ unsafe fn from_raw_fd(fd: RawFd) -> Self {
+ assert_ne!(fd, u32::MAX as RawFd);
+ // SAFETY: we just asserted that the value is in the valid range and isn't `-1` (the only value bigger than `0xFF_FF_FF_FE` unsigned)
+ #[allow(unused_unsafe)]
+ unsafe {
+ Self { fd }
+ }
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl Drop for OwnedFd {
+ #[inline]
+ fn drop(&mut self) {
+ unsafe {
+ // Errors are ignored when closing a file descriptor. The reason
+ // for this is that if an error occurs we don't actually know if
+ // the file descriptor was closed or not, and if we retried (for
+ // something like EINTR), we might close another valid file
+ // descriptor opened after we closed ours.
+ let _ = close(self.fd as _);
+ }
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl fmt::Debug for BorrowedFd<'_> {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_struct("BorrowedFd").field("fd", &self.fd).finish()
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl fmt::Debug for OwnedFd {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_struct("OwnedFd").field("fd", &self.fd).finish()
+ }
+}
+
+/// A trait to borrow the file descriptor from an underlying object.
+///
+/// This is only available on unix platforms and must be imported in order to
+/// call the method. Windows platforms have a corresponding `AsHandle` and
+/// `AsSocket` set of traits.
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+pub trait AsFd {
+ /// Borrows the file descriptor.
+ ///
+ /// # Example
+ ///
+ /// ```rust,no_run
+ /// # #![feature(io_safety)]
+ /// use std::fs::File;
+ /// # use std::io;
+ /// # #[cfg(target_os = "wasi")]
+ /// # use std::os::wasi::io::{AsFd, BorrowedFd};
+ /// # #[cfg(unix)]
+ /// # use std::os::unix::io::{AsFd, BorrowedFd};
+ ///
+ /// let mut f = File::open("foo.txt")?;
+ /// # #[cfg(any(unix, target_os = "wasi"))]
+ /// let borrowed_fd: BorrowedFd<'_> = f.as_fd();
+ /// # Ok::<(), io::Error>(())
+ /// ```
+ #[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+ fn as_fd(&self) -> BorrowedFd<'_>;
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl<T: AsFd> AsFd for &T {
+ #[inline]
+ fn as_fd(&self) -> BorrowedFd<'_> {
+ T::as_fd(self)
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl<T: AsFd> AsFd for &mut T {
+ #[inline]
+ fn as_fd(&self) -> BorrowedFd<'_> {
+ T::as_fd(self)
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl AsFd for BorrowedFd<'_> {
+ #[inline]
+ fn as_fd(&self) -> BorrowedFd<'_> {
+ *self
+ }
+}
+
+#[cfg_attr(staged_api, unstable(feature = "io_safety", issue = "87074"))]
+impl AsFd for OwnedFd {
+ #[inline]
+ fn as_fd(&self) -> BorrowedFd<'_> {
+ // Safety: `OwnedFd` and `BorrowedFd` have the same validity
+ // invariants, and the `BorrowedFd` is bounded by the lifetime
+ // of `&self`.
+ unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
+ }
+}
diff --git a/vendor/rustix/src/io/fd/raw.rs b/vendor/rustix/src/io/fd/raw.rs
new file mode 100644
index 000000000..44322d9fe
--- /dev/null
+++ b/vendor/rustix/src/io/fd/raw.rs
@@ -0,0 +1,159 @@
+//! The following is derived from Rust's
+//! library/std/src/os/fd/raw.rs at revision
+//! fa68e73e9947be8ffc5b3b46d899e4953a44e7e9.
+//!
+//! Raw Unix-like file descriptors.
+
+#![cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
+#![allow(unsafe_code)]
+
+use crate::imp::c;
+
+/// Raw file descriptors.
+#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
+pub type RawFd = c::c_int;
+
+/// A trait to extract the raw file descriptor from an underlying object.
+///
+/// This is only available on unix and WASI platforms and must be imported in
+/// order to call the method. Windows platforms have a corresponding
+/// `AsRawHandle` and `AsRawSocket` set of traits.
+#[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
+pub trait AsRawFd {
+ /// Extracts the raw file descriptor.
+ ///
+ /// This function is typically used to **borrow** an owned file descriptor.
+ /// When used in this way, this method does **not** pass ownership of the
+ /// raw file descriptor to the caller, and the file descriptor is only
+ /// guaranteed to be valid while the original object has not yet been
+ /// destroyed.
+ ///
+ /// However, borrowing is not strictly required. See [`AsFd::as_fd`]
+ /// for an API which strictly borrows a file descriptor.
+ ///
+ /// # Example
+ ///
+ /// ```no_run
+ /// use std::fs::File;
+ /// # use std::io;
+ /// #[cfg(unix)]
+ /// use std::os::unix::io::{AsRawFd, RawFd};
+ /// #[cfg(target_os = "wasi")]
+ /// use std::os::wasi::io::{AsRawFd, RawFd};
+ ///
+ /// let mut f = File::open("foo.txt")?;
+ /// // `raw_fd` is only valid as long as `f` exists.
+ /// #[cfg(any(unix, target_os = "wasi"))]
+ /// let raw_fd: RawFd = f.as_raw_fd();
+ /// # Ok::<(), io::Error>(())
+ /// ```
+ #[cfg_attr(staged_api, stable(feature = "rust1", since = "1.0.0"))]
+ fn as_raw_fd(&self) -> RawFd;
+}
+
+/// A trait to express the ability to construct an object from a raw file
+/// descriptor.
+#[cfg_attr(staged_api, stable(feature = "from_raw_os", since = "1.1.0"))]
+pub trait FromRawFd {
+ /// Constructs a new instance of `Self` from the given raw file
+ /// descriptor.
+ ///
+ /// This function is typically used to **consume ownership** of the
+ /// specified file descriptor. When used in this way, the returned object
+ /// will take responsibility for closing it when the object goes out of
+ /// scope.
+ ///
+ /// However, consuming ownership is not strictly required. Use a
+ /// [`From<OwnedFd>::from`] implementation for an API which strictly
+ /// consumes ownership.
+ ///
+ /// # Safety
+ ///
+ /// The `fd` passed in must be a valid an open file descriptor.
+ ///
+ /// # Example
+ ///
+ /// ```no_run
+ /// use std::fs::File;
+ /// # use std::io;
+ /// #[cfg(unix)]
+ /// use std::os::unix::io::{FromRawFd, IntoRawFd, RawFd};
+ /// #[cfg(target_os = "wasi")]
+ /// use std::os::wasi::io::{FromRawFd, IntoRawFd, RawFd};
+ ///
+ /// let f = File::open("foo.txt")?;
+ /// # #[cfg(any(unix, target_os = "wasi"))]
+ /// let raw_fd: RawFd = f.into_raw_fd();
+ /// // SAFETY: no other functions should call `from_raw_fd`, so there
+ /// // is only one owner for the file descriptor.
+ /// # #[cfg(any(unix, target_os = "wasi"))]
+ /// let f = unsafe { File::from_raw_fd(raw_fd) };
+ /// # Ok::<(), io::Error>(())
+ /// ```
+ #[cfg_attr(staged_api, stable(feature = "from_raw_os", since = "1.1.0"))]
+ unsafe fn from_raw_fd(fd: RawFd) -> Self;
+}
+
+/// A trait to express the ability to consume an object and acquire ownership of
+/// its raw file descriptor.
+#[cfg_attr(staged_api, stable(feature = "into_raw_os", since = "1.4.0"))]
+pub trait IntoRawFd {
+ /// Consumes this object, returning the raw underlying file descriptor.
+ ///
+ /// This function is typically used to **transfer ownership** of the underlying
+ /// file descriptor to the caller. When used in this way, callers are then the unique
+ /// owners of the file descriptor and must close it once it's no longer needed.
+ ///
+ /// However, transferring ownership is not strictly required. Use a
+ /// [`Into<OwnedFd>::into`] implementation for an API which strictly
+ /// transfers ownership.
+ ///
+ /// # Example
+ ///
+ /// ```no_run
+ /// use std::fs::File;
+ /// # use std::io;
+ /// #[cfg(unix)]
+ /// use std::os::unix::io::{IntoRawFd, RawFd};
+ /// #[cfg(target_os = "wasi")]
+ /// use std::os::wasi::io::{IntoRawFd, RawFd};
+ ///
+ /// let f = File::open("foo.txt")?;
+ /// #[cfg(any(unix, target_os = "wasi"))]
+ /// let raw_fd: RawFd = f.into_raw_fd();
+ /// # Ok::<(), io::Error>(())
+ /// ```
+ #[cfg_attr(staged_api, stable(feature = "into_raw_os", since = "1.4.0"))]
+ fn into_raw_fd(self) -> RawFd;
+}
+
+#[cfg_attr(
+ staged_api,
+ stable(feature = "raw_fd_reflexive_traits", since = "1.48.0")
+)]
+impl AsRawFd for RawFd {
+ #[inline]
+ fn as_raw_fd(&self) -> RawFd {
+ *self
+ }
+}
+#[cfg_attr(
+ staged_api,
+ stable(feature = "raw_fd_reflexive_traits", since = "1.48.0")
+)]
+impl IntoRawFd for RawFd {
+ #[inline]
+ fn into_raw_fd(self) -> RawFd {
+ self
+ }
+}
+#[cfg_attr(
+ staged_api,
+ stable(feature = "raw_fd_reflexive_traits", since = "1.48.0")
+)]
+impl FromRawFd for RawFd {
+ #[inline]
+ unsafe fn from_raw_fd(fd: RawFd) -> RawFd {
+ fd
+ }
+}