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Diffstat (limited to 'vendor/rustix/src/process/pidfd_getfd.rs')
-rw-r--r-- | vendor/rustix/src/process/pidfd_getfd.rs | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/vendor/rustix/src/process/pidfd_getfd.rs b/vendor/rustix/src/process/pidfd_getfd.rs new file mode 100644 index 0000000..4c7696f --- /dev/null +++ b/vendor/rustix/src/process/pidfd_getfd.rs @@ -0,0 +1,56 @@ +//! The [`pidfd_getfd`] function and supporting types. + +#![allow(unsafe_code)] +use crate::fd::OwnedFd; +use crate::{backend, io}; +use backend::fd::{AsFd, RawFd}; + +/// Raw file descriptor in another process. +/// +/// A distinct type alias is used here to inform the user that normal file +/// descriptors from the calling process should not be used. The provided file +/// descriptor is used by the kernel as the index into the file descriptor +/// table of an entirely different process. +pub type ForeignRawFd = RawFd; + +bitflags::bitflags! { + /// All flags are reserved for future use. + #[repr(transparent)] + #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)] + pub struct PidfdGetfdFlags: backend::c::c_uint { + /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags> + const _ = !0; + } +} + +/// `syscall(SYS_pidfd_getfd, pidfd, flags)`—Obtain a duplicate of another +/// process' file descriptor. +/// +/// # References +/// - [Linux] +/// +/// # Warning +/// +/// This function is generally safe for the calling process, but it can impact +/// the target process in unexpected ways. If you want to ensure that Rust I/O +/// safety assumptions continue to hold in the target process, then the target +/// process must have communicated the file description number to the calling +/// process from a value of a type that implements `AsRawFd`, and the target +/// process must not drop that value until after the calling process has +/// returned from `pidfd_getfd`. +/// +/// When `pidfd_getfd` is used to debug the target, or the target is not a Rust +/// aplication, or `pidfd_getfd` is used in any other way, then extra care +/// should be taken to avoid unexpected behaviour or crashes. +/// +/// For further details, see the references above. +/// +/// [Linux]: https://man7.org/linux/man-pages/man2/pidfd_getfd.2.html +#[inline] +pub fn pidfd_getfd<Fd: AsFd>( + pidfd: Fd, + targetfd: ForeignRawFd, + flags: PidfdGetfdFlags, +) -> io::Result<OwnedFd> { + backend::process::syscalls::pidfd_getfd(pidfd.as_fd(), targetfd, flags) +} |