Amjad50/OS: Added support for ExitStatusExt

This allows us to create `ExitStatus` struct

Author: Amjad50

library/std/src/os/amjad_os/mod.rs

@@ -2,6 +2,7 @@
 
 pub mod ffi;
 pub mod io;
+pub mod process;
 
 /// A prelude for conveniently writing platform-specific code.
 ///

library/std/src/os/amjad_os/process.rs

@@ -0,0 +1,74 @@
+//! amjad_os-specific extensions to primitives in the [`std::process`] module.
+//!
+//! [`std::process`]: crate::process
+
+#![stable(feature = "rust1", since = "1.0.0")]
+
+use crate::{
+    process,
+    sealed::Sealed,
+    sys_common::{AsInner, FromInner},
+};
+
+/// amjad_os extension to [`process::ExitStatus`] that is based on unix as below
+/// ...
+///
+/// Unix-specific extensions to [`process::ExitStatus`] and
+/// [`ExitStatusError`](process::ExitStatusError).
+///
+/// On Unix, `ExitStatus` **does not necessarily represent an exit status**, as
+/// passed to the `_exit` system call or returned by
+/// [`ExitStatus::code()`](crate::process::ExitStatus::code).  It represents **any wait status**
+/// as returned by one of the `wait` family of system
+/// calls.
+///
+/// A Unix wait status (a Rust `ExitStatus`) can represent a Unix exit status, but can also
+/// represent other kinds of process event.
+///
+/// This trait is sealed: it cannot be implemented outside the standard library.
+/// This is so that future additional methods are not breaking changes.
+#[stable(feature = "rust1", since = "1.0.0")]
+pub trait ExitStatusExt: Sealed {
+    /// Creates a new `ExitStatus` or `ExitStatusError` from the raw underlying integer status
+    /// value from `wait`
+    ///
+    /// The value should be a **wait status, not an exit status**.
+    ///
+    /// # Panics
+    ///
+    /// Panics on an attempt to make an `ExitStatusError` from a wait status of `0`.
+    ///
+    /// Making an `ExitStatus` always succeeds and never panics.
+    #[stable(feature = "exit_status_from", since = "1.12.0")]
+    fn from_raw(raw: i32) -> Self;
+
+    /// Returns the underlying raw `wait` status.
+    ///
+    /// The returned integer is a **wait status, not an exit status**.
+    #[stable(feature = "unix_process_wait_more", since = "1.58.0")]
+    fn into_raw(self) -> i32;
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ExitStatusExt for process::ExitStatus {
+    fn from_raw(raw: i32) -> Self {
+        process::ExitStatus::from_inner(From::from(raw))
+    }
+
+    fn into_raw(self) -> i32 {
+        self.as_inner().into_raw().into()
+    }
+}
+
+#[unstable(feature = "exit_status_error", issue = "84908")]
+impl ExitStatusExt for process::ExitStatusError {
+    fn from_raw(raw: i32) -> Self {
+        process::ExitStatus::from_raw(raw)
+            .exit_ok()
+            .expect_err("<ExitStatusError as ExitStatusExt>::from_raw(0) but zero is not an error")
+    }
+
+    fn into_raw(self) -> i32 {
+        self.into_status().into_raw()
+    }
+}

library/std/src/sys/amjad_os/process.rs

@@ -297,6 +297,17 @@ impl ExitStatus {
     pub fn code(&self) -> Option<i32> {
         Some(self.0)
     }
+
+    pub fn into_raw(&self) -> i32 {
+        self.0
+    }
+}
+
+/// Converts a raw `i32` to a type-safe `ExitStatus` by wrapping it without copying.
+impl From<i32> for ExitStatus {
+    fn from(a: i32) -> ExitStatus {
+        ExitStatus(a)
+    }
 }
 
 impl fmt::Display for ExitStatus {