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Diffstat (limited to 'vendor/rustix/src/pid.rs')
| -rw-r--r-- | vendor/rustix/src/pid.rs | 135 |
1 files changed, 0 insertions, 135 deletions
diff --git a/vendor/rustix/src/pid.rs b/vendor/rustix/src/pid.rs deleted file mode 100644 index aa61892f..00000000 --- a/vendor/rustix/src/pid.rs +++ /dev/null @@ -1,135 +0,0 @@ -//! The `Pid` type. - -#![allow(unsafe_code)] - -use core::num::NonZeroI32; - -/// A process identifier as a raw integer. -pub type RawPid = i32; - -/// `pid_t`—A non-zero Unix process ID. -/// -/// This is a pid, and not a pidfd. It is not a file descriptor, and the -/// process it refers to could disappear at any time and be replaced by -/// another, unrelated, process. -/// -/// On Linux, `Pid` values are also used to identify threads. -#[repr(transparent)] -#[derive(Copy, Clone, Eq, PartialEq, Debug, Hash)] -pub struct Pid(NonZeroI32); - -impl Pid { - /// A `Pid` corresponding to the init process (pid 1). - pub const INIT: Self = Self(match NonZeroI32::new(1) { - Some(n) => n, - None => panic!("unreachable"), - }); - - /// Converts a `RawPid` into a `Pid`. - /// - /// Returns `Some` for positive values, and `None` for zero values. - /// - /// This is safe because a `Pid` is a number without any guarantees for the - /// kernel. Non-child `Pid`s are always racy for any syscalls, but can only - /// cause logic errors. If you want race-free access to or control of - /// non-child processes, please consider other mechanisms like [pidfd] on - /// Linux. - /// - /// Passing a negative number doesn't invoke undefined behavior, but it - /// may cause unexpected behavior. - /// - /// [pidfd]: https://man7.org/linux/man-pages/man2/pidfd_open.2.html - #[inline] - pub const fn from_raw(raw: RawPid) -> Option<Self> { - debug_assert!(raw >= 0); - match NonZeroI32::new(raw) { - Some(non_zero) => Some(Self(non_zero)), - None => None, - } - } - - /// Converts a known positive `RawPid` into a `Pid`. - /// - /// Passing a negative number doesn't invoke undefined behavior, but it - /// may cause unexpected behavior. - /// - /// # Safety - /// - /// The caller must guarantee `raw` is non-zero. - #[inline] - pub const unsafe fn from_raw_unchecked(raw: RawPid) -> Self { - debug_assert!(raw > 0); - Self(NonZeroI32::new_unchecked(raw)) - } - - /// Creates a `Pid` holding the ID of the given child process. - #[cfg(feature = "std")] - #[inline] - pub fn from_child(child: &std::process::Child) -> Self { - let id = child.id(); - // SAFETY: We know the returned ID is valid because it came directly - // from an OS API. - unsafe { Self::from_raw_unchecked(id as i32) } - } - - /// Converts a `Pid` into a `NonZeroI32`. - #[inline] - pub const fn as_raw_nonzero(self) -> NonZeroI32 { - self.0 - } - - /// Converts an `Option<Pid>` into a `RawPid`. - #[inline] - pub const fn as_raw(pid: Option<Self>) -> RawPid { - match pid { - Some(pid) => pid.0.get(), - None => 0, - } - } - - /// Test whether this pid represents the init process ([`Pid::INIT`]). - #[inline] - pub const fn is_init(self) -> bool { - self.0.get() == Self::INIT.0.get() - } -} - -#[cfg(test)] -mod tests { - use super::*; - - #[test] - fn test_sizes() { - use core::mem::transmute; - - assert_eq_size!(RawPid, NonZeroI32); - assert_eq_size!(RawPid, Pid); - assert_eq_size!(RawPid, Option<Pid>); - - // Rustix doesn't depend on `Option<Pid>` matching the ABI of a raw integer - // for correctness, but it should work nonetheless. - const_assert_eq!(0 as RawPid, unsafe { - transmute::<Option<Pid>, RawPid>(None) - }); - const_assert_eq!(4567 as RawPid, unsafe { - transmute::<Option<Pid>, RawPid>(Some(Pid::from_raw_unchecked(4567))) - }); - } - - #[test] - fn test_ctors() { - use std::num::NonZeroI32; - assert!(Pid::from_raw(0).is_none()); - assert_eq!( - Pid::from_raw(77).unwrap().as_raw_nonzero(), - NonZeroI32::new(77).unwrap() - ); - assert_eq!(Pid::as_raw(Pid::from_raw(77)), 77); - } - - #[test] - fn test_specials() { - assert!(Pid::from_raw(1).unwrap().is_init()); - assert_eq!(Pid::from_raw(1).unwrap(), Pid::INIT); - } -} |
