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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
commit | 698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch) | |
tree | 173a775858bd501c378080a10dca74132f05bc50 /vendor/rustix/src/io/fd | |
parent | Initial commit. (diff) | |
download | rustc-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.rs | 17 | ||||
-rw-r--r-- | vendor/rustix/src/io/fd/owned.rs | 252 | ||||
-rw-r--r-- | vendor/rustix/src/io/fd/raw.rs | 159 |
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 + } +} |