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Diffstat (limited to 'vendor/rustix-0.36.5/src/io/fd/owned.rs')
| -rw-r--r-- | vendor/rustix-0.36.5/src/io/fd/owned.rs | 252 |
1 files changed, 0 insertions, 252 deletions
diff --git a/vendor/rustix-0.36.5/src/io/fd/owned.rs b/vendor/rustix-0.36.5/src/io/fd/owned.rs deleted file mode 100644 index c2972b073..000000000 --- a/vendor/rustix-0.36.5/src/io/fd/owned.rs +++ /dev/null @@ -1,252 +0,0 @@ -//! 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::io::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::io::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()) } - } -} |