wip: impl the std side

src/lib.rs

@@ -5,8 +5,8 @@
 
 pub(crate) mod generic_wrap;
 
-// #[cfg(feature = "std")]
-// pub mod std;
+#[cfg(feature = "std")]
+pub mod std;
 
 #[cfg(feature = "tokio1")]
 pub mod tokio;
@@ -23,5 +23,5 @@ mod windows;
 #[derive(Debug)]
 pub(crate) enum ChildExitStatus {
 	Running,
-	Exited(std::process::ExitStatus),
+	Exited(::std::process::ExitStatus),
 }

src/std.rs

@@ -0,0 +1,29 @@
+#[doc(inline)]
+pub use core::{StdChildWrapper, StdCommandWrap, StdCommandWrapper};
+#[cfg(all(windows, feature = "creation-flags"))]
+#[doc(inline)]
+pub use creation_flags::CreationFlags;
+#[cfg(all(windows, feature = "job-object"))]
+#[doc(inline)]
+pub use job_object::JobObject;
+#[cfg(feature = "kill-on-drop")]
+#[doc(inline)]
+pub use kill_on_drop::KillOnDrop;
+#[cfg(all(unix, feature = "process-group"))]
+#[doc(inline)]
+pub use process_group::{ProcessGroup, ProcessGroupChild};
+#[cfg(all(unix, feature = "process-session"))]
+#[doc(inline)]
+pub use process_session::ProcessSession;
+
+mod core;
+#[cfg(all(windows, feature = "creation-flags"))]
+mod creation_flags;
+#[cfg(all(windows, feature = "job-object"))]
+mod job_object;
+#[cfg(feature = "kill-on-drop")]
+mod kill_on_drop;
+#[cfg(all(unix, feature = "process-group"))]
+mod process_group;
+#[cfg(all(unix, feature = "process-session"))]
+mod process_session;

src/std/core.rs

@@ -0,0 +1,104 @@
+use std::{
+	io::Result,
+	process::{Child, ChildStderr, ChildStdin, ChildStdout, Command, ExitStatus, Output},
+};
+
+#[cfg(unix)]
+use nix::{
+	sys::signal::{kill, Signal},
+	unistd::Pid,
+};
+
+crate::generic_wrap::Wrap!(StdCommandWrap, Command, StdCommandWrapper, StdChildWrapper);
+
+pub trait StdCommandWrapper: std::fmt::Debug {
+	// process-wrap guarantees that `other` will be of the same type as `self`
+	// note that other crates that may use this trait should guarantee this, but
+	// that cannot be enforced by the type system, so you should still panic if
+	// downcasting fails, instead of potentially causing UB
+	fn extend(&mut self, _other: Box<dyn StdCommandWrapper>) {}
+
+	fn pre_spawn(&mut self, _command: &mut Command, _core: &StdCommandWrap) -> Result<()> {
+		Ok(())
+	}
+
+	fn post_spawn(&mut self, _child: &mut Child, _core: &StdCommandWrap) -> Result<()> {
+		Ok(())
+	}
+
+	fn wrap_child(
+		&mut self,
+		child: Box<dyn StdChildWrapper>,
+		_core: &StdCommandWrap,
+	) -> Result<Box<dyn StdChildWrapper>> {
+		Ok(child)
+	}
+}
+
+pub trait StdChildWrapper: std::fmt::Debug + Send + Sync {
+	fn inner(&self) -> &Child;
+	fn inner_mut(&mut self) -> &mut Child;
+	fn into_inner(self: Box<Self>) -> Child;
+
+	fn stdin(&mut self) -> &mut Option<ChildStdin> {
+		&mut self.inner_mut().stdin
+	}
+
+	fn stdout(&mut self) -> &mut Option<ChildStdout> {
+		&mut self.inner_mut().stdout
+	}
+
+	fn stderr(&mut self) -> &mut Option<ChildStderr> {
+		&mut self.inner_mut().stderr
+	}
+
+	fn id(&self) -> u32 {
+		self.inner().id()
+	}
+
+	fn kill(&mut self) -> Result<()> {
+		self.start_kill()?;
+		self.wait()?;
+		Ok(())
+	}
+
+	fn start_kill(&mut self) -> Result<()> {
+		self.inner_mut().start_kill()
+	}
+
+	fn try_wait(&mut self) -> Result<Option<ExitStatus>> {
+		self.inner_mut().try_wait()
+	}
+
+	fn wait(&mut self) -> Result<ExitStatus> {
+		self.inner_mut().wait()
+	}
+
+	fn wait_with_output(self: Box<Self>) -> Result<Output>
+	where
+		Self: 'static,
+	{
+		todo!()
+	}
+
+	#[cfg(unix)]
+	fn signal(&self, sig: Signal) -> Result<()> {
+		kill(
+			Pid::from_raw(i32::try_from(self.id()).map_err(std::io::Error::other)?),
+			sig,
+		)
+		.map_err(std::io::Error::from)
+	}
+}
+
+impl StdChildWrapper for Child {
+	fn inner(&self) -> &Child {
+		self
+	}
+	fn inner_mut(&mut self) -> &mut Child {
+		self
+	}
+	fn into_inner(self: Box<Self>) -> Child {
+		*self
+	}
+}

src/std/creation_flags.rs

@@ -0,0 +1,15 @@
+use std::{io::Result, os::windows::process::CommandExt, process::Command};
+
+use windows::Win32::System::Threading::PROCESS_CREATION_FLAGS;
+
+use super::{StdCommandWrap, StdCommandWrapper};
+
+#[derive(Debug, Clone)]
+pub struct CreationFlags(pub PROCESS_CREATION_FLAGS);
+
+impl StdCommandWrapper for CreationFlags {
+	fn pre_spawn(&mut self, command: &mut Command, _core: &StdCommandWrap) -> Result<()> {
+		command.creation_flags((self.0).0);
+		Ok(())
+	}
+}

src/std/job_object.rs

@@ -0,0 +1,142 @@
+use std::{
+	io::Result,
+	os::windows::{io::AsRawHandle, process::CommandExt},
+	process::{Child, Command, ExitStatus},
+	time::Duration,
+};
+
+use tracing::{debug, instrument};
+use windows::Win32::{
+	Foundation::{CloseHandle, HANDLE},
+	System::Threading::CREATE_SUSPENDED,
+};
+
+use crate::{
+	windows::{make_job_object, resume_threads, terminate_job, wait_on_job, JobPort},
+	ChildExitStatus,
+};
+
+#[cfg(feature = "creation-flags")]
+use super::CreationFlags;
+#[cfg(feature = "kill-on-drop")]
+use super::KillOnDrop;
+use super::{StdChildWrapper, StdCommandWrap, StdCommandWrapper};
+
+#[derive(Debug)]
+pub struct JobObject;
+
+impl StdCommandWrapper for JobObject {
+	#[instrument(level = "debug", skip(self))]
+	fn pre_spawn(&mut self, command: &mut Command, core: &StdCommandWrap) -> Result<()> {
+		let mut flags = CREATE_SUSPENDED;
+		#[cfg(feature = "creation-flags")]
+		if let Some(CreationFlags(user_flags)) = core.get_wrap::<CreationFlags>() {
+			flags |= *user_flags;
+		}
+
+		command.creation_flags(flags.0);
+		Ok(())
+	}
+
+	#[instrument(level = "debug", skip(self))]
+	fn wrap_child(
+		&mut self,
+		inner: Box<dyn StdChildWrapper>,
+		core: &StdCommandWrap,
+	) -> Result<Box<dyn StdChildWrapper>> {
+		#[cfg(feature = "kill-on-drop")]
+		let kill_on_drop = core.has_wrap::<KillOnDrop>();
+		#[cfg(not(feature = "kill-on-drop"))]
+		let kill_on_drop = false;
+
+		#[cfg(feature = "creation-flags")]
+		let create_suspended = core
+			.get_wrap::<CreationFlags>()
+			.map_or(false, |flags| flags.0.contains(CREATE_SUSPENDED));
+		#[cfg(not(feature = "creation-flags"))]
+		let create_suspended = false;
+
+		debug!(
+			?kill_on_drop,
+			?create_suspended,
+			"options from other wrappers"
+		);
+
+		let handle = HANDLE(inner.inner().as_raw_handle() as _);
+
+		let job_port = make_job_object(handle, kill_on_drop)?;
+
+		// only resume if the user didn't specify CREATE_SUSPENDED
+		if !create_suspended {
+			resume_threads(handle)?;
+		}
+
+		Ok(Box::new(JobObjectChild::new(inner, job_port)))
+	}
+}
+
+#[derive(Debug)]
+pub struct JobObjectChild {
+	inner: Box<dyn StdChildWrapper>,
+	exit_status: ChildExitStatus,
+	job_port: JobPort,
+}
+
+impl JobObjectChild {
+	#[instrument(level = "debug", skip(job_port))]
+	pub(crate) fn new(inner: Box<dyn StdChildWrapper>, job_port: JobPort) -> Self {
+		Self {
+			inner,
+			exit_status: ChildExitStatus::Running,
+			job_port,
+		}
+	}
+}
+
+impl StdChildWrapper for JobObjectChild {
+	fn inner(&self) -> &Child {
+		self.inner.inner()
+	}
+	fn inner_mut(&mut self) -> &mut Child {
+		self.inner.inner_mut()
+	}
+	fn into_inner(self: Box<Self>) -> Child {
+		// manually drop the completion port
+		let its = std::mem::ManuallyDrop::new(self.job_port);
+		unsafe { CloseHandle(its.completion_port) }.ok();
+		// we leave the job handle unclosed, otherwise the Child is useless
+		// (as closing it will terminate the job)
+
+		self.inner.into_inner()
+	}
+
+	#[instrument(level = "debug", skip(self))]
+	fn start_kill(&mut self) -> Result<()> {
+		terminate_job(self.job_port.job, 1)
+	}
+
+	#[instrument(level = "debug", skip(self))]
+	fn wait(&mut self) -> Result<ExitStatus> {
+		if let ChildExitStatus::Exited(status) = &self.exit_status {
+			return Ok(*status);
+		}
+
+		// always wait for parent to exit first, as by the time it does,
+		// it's likely that all its children have already exited.
+		let status = self.inner.wait()?;
+		self.exit_status = ChildExitStatus::Exited(status);
+
+		// nevertheless, now wait and make sure we reap all children.
+		let JobPort {
+			completion_port, ..
+		} = self.job_port;
+		wait_on_job(completion_port, None)?;
+		Ok(status)
+	}
+
+	#[instrument(level = "debug", skip(self))]
+	fn try_wait(&mut self) -> Result<Option<ExitStatus>> {
+		wait_on_job(self.job_port.completion_port, Some(Duration::ZERO))?;
+		self.inner.try_wait()
+	}
+}

src/std/kill_on_drop.rs

@@ -0,0 +1,13 @@
+use std::{io::Result, process::Command};
+
+use super::{StdCommandWrap, StdCommandWrapper};
+
+#[derive(Debug)]
+pub struct KillOnDrop;
+
+impl StdCommandWrapper for KillOnDrop {
+	fn pre_spawn(&mut self, command: &mut Command, _core: &StdCommandWrap) -> Result<()> {
+		command.kill_on_drop(true);
+		Ok(())
+	}
+}