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Diffstat (limited to 'vendor/rustix/src/pid.rs')
-rw-r--r-- | vendor/rustix/src/pid.rs | 104 |
1 files changed, 0 insertions, 104 deletions
diff --git a/vendor/rustix/src/pid.rs b/vendor/rustix/src/pid.rs deleted file mode 100644 index 5f2b9ad..0000000 --- a/vendor/rustix/src/pid.rs +++ /dev/null @@ -1,104 +0,0 @@ -//! The `Pid` type. - -#![allow(unsafe_code)] - -use crate::backend::c; -use core::num::NonZeroI32; - -/// A process identifier as a raw integer. -pub type RawPid = c::pid_t; - -/// `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. -#[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 `RawPid`s. Otherwise, returns `None`. - /// - /// 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. - /// - /// [pidfd]: https://man7.org/linux/man-pages/man2/pidfd_open.2.html - #[inline] - pub const fn from_raw(raw: RawPid) -> Option<Self> { - if raw > 0 { - // SAFETY: We just checked that `raw > 0`. - unsafe { Some(Self::from_raw_unchecked(raw)) } - } else { - None - } - } - - /// Converts a known positive `RawPid` into a `Pid`. - /// - /// # Safety - /// - /// The caller must guarantee `raw` is positive. - #[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 fn as_raw(pid: Option<Self>) -> RawPid { - pid.map_or(0, |pid| pid.0.get()) - } - - /// Test whether this pid represents the init process (pid 1). - #[inline] - pub const fn is_init(self) -> bool { - self.0.get() == Self::INIT.0.get() - } -} - -#[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))) - }); -} |