Files
rust/library/std/src/os/windows/process.rs
bors e2d6aa77ed Auto merge of #98704 - vthib:impl-from-raw-for-childstd-structs, r=dtolnay
Implement From<OwnedFd/Handle> for ChildStdin/out/err object

## Summary

Comments in `library/std/src/process.rs` ( ab08639e59 ) indicates that `ChildStdin`, `ChildStdout`, `ChildStderr` implements some traits that are not actually implemented: `FromRawFd`, `FromRawHandle`, and the `From<OwnedFd>/From<OwnedHandle>` from the io_safety feature.

In this PR I implement `FromRawHandle` and `FromRawFd` for those 3 objects.

## Usecase

I have a usecase where those implementations are basically needed. I want to customize
in the `Command::spawn` API how the pipes for the parent/child communications are created (mainly to strengthen the security attributes on them). I can properly setup the pipes,
and the "child" handles can be provided to `Child::spawn` easily using `Stdio::from_raw_handle`. However, there is no way to generate the `ChildStd*` objects from the raw handle of the created name pipe, which would be very useful to still expose the same API
than in other OS (basically a `spawn(...) -> (Child, ChildStdin, ChildStdout, ChildSterr)`, where on windows this is customized), and to for example use `tokio::ChildStdin::from_std` afterwards.

## Questions

* Are those impls OK to add? I have searched to see if those impls were missing on purpose, or if it was just never implemented because never needed. I haven't found any indication on why they couldn't be added, although the user clearly has to be very careful that the handle provided makes sense (i think, mainly that it is in overlapped mode for windows).
* If this change is ok, adding the impls for the io_safety feature would probably be best, or should it be done in another PR?
* I just copy-pasted the `#[stable(...)]` attributes, but the `since` value has to be updated, I'm not sure to which value.
2023-09-28 09:59:03 +00:00

368 lines
14 KiB
Rust

//! Windows-specific extensions to primitives in the [`std::process`] module.
//!
//! [`std::process`]: crate::process
#![stable(feature = "process_extensions", since = "1.2.0")]
use crate::ffi::OsStr;
use crate::os::windows::io::{
AsHandle, AsRawHandle, BorrowedHandle, FromRawHandle, IntoRawHandle, OwnedHandle, RawHandle,
};
use crate::process;
use crate::sealed::Sealed;
use crate::sys;
use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
#[stable(feature = "process_extensions", since = "1.2.0")]
impl FromRawHandle for process::Stdio {
unsafe fn from_raw_handle(handle: RawHandle) -> process::Stdio {
let handle = sys::handle::Handle::from_raw_handle(handle as *mut _);
let io = sys::process::Stdio::Handle(handle);
process::Stdio::from_inner(io)
}
}
#[stable(feature = "io_safety", since = "1.63.0")]
impl From<OwnedHandle> for process::Stdio {
fn from(handle: OwnedHandle) -> process::Stdio {
let handle = sys::handle::Handle::from_inner(handle);
let io = sys::process::Stdio::Handle(handle);
process::Stdio::from_inner(io)
}
}
#[stable(feature = "process_extensions", since = "1.2.0")]
impl AsRawHandle for process::Child {
#[inline]
fn as_raw_handle(&self) -> RawHandle {
self.as_inner().handle().as_raw_handle() as *mut _
}
}
#[stable(feature = "io_safety", since = "1.63.0")]
impl AsHandle for process::Child {
#[inline]
fn as_handle(&self) -> BorrowedHandle<'_> {
self.as_inner().handle().as_handle()
}
}
#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawHandle for process::Child {
fn into_raw_handle(self) -> RawHandle {
self.into_inner().into_handle().into_raw_handle() as *mut _
}
}
#[stable(feature = "io_safety", since = "1.63.0")]
impl From<process::Child> for OwnedHandle {
fn from(child: process::Child) -> OwnedHandle {
child.into_inner().into_handle().into_inner()
}
}
#[stable(feature = "process_extensions", since = "1.2.0")]
impl AsRawHandle for process::ChildStdin {
#[inline]
fn as_raw_handle(&self) -> RawHandle {
self.as_inner().handle().as_raw_handle() as *mut _
}
}
#[stable(feature = "process_extensions", since = "1.2.0")]
impl AsRawHandle for process::ChildStdout {
#[inline]
fn as_raw_handle(&self) -> RawHandle {
self.as_inner().handle().as_raw_handle() as *mut _
}
}
#[stable(feature = "process_extensions", since = "1.2.0")]
impl AsRawHandle for process::ChildStderr {
#[inline]
fn as_raw_handle(&self) -> RawHandle {
self.as_inner().handle().as_raw_handle() as *mut _
}
}
#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawHandle for process::ChildStdin {
fn into_raw_handle(self) -> RawHandle {
self.into_inner().into_handle().into_raw_handle() as *mut _
}
}
#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawHandle for process::ChildStdout {
fn into_raw_handle(self) -> RawHandle {
self.into_inner().into_handle().into_raw_handle() as *mut _
}
}
#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawHandle for process::ChildStderr {
fn into_raw_handle(self) -> RawHandle {
self.into_inner().into_handle().into_raw_handle() as *mut _
}
}
/// Create a `ChildStdin` from the provided `OwnedHandle`.
///
/// The provided handle must be asynchronous, as reading and
/// writing from and to it is implemented using asynchronous APIs.
#[stable(feature = "child_stream_from_fd", since = "CURRENT_RUSTC_VERSION")]
impl From<OwnedHandle> for process::ChildStdin {
fn from(handle: OwnedHandle) -> process::ChildStdin {
let handle = sys::handle::Handle::from_inner(handle);
let pipe = sys::pipe::AnonPipe::from_inner(handle);
process::ChildStdin::from_inner(pipe)
}
}
/// Create a `ChildStdout` from the provided `OwnedHandle`.
///
/// The provided handle must be asynchronous, as reading and
/// writing from and to it is implemented using asynchronous APIs.
#[stable(feature = "child_stream_from_fd", since = "CURRENT_RUSTC_VERSION")]
impl From<OwnedHandle> for process::ChildStdout {
fn from(handle: OwnedHandle) -> process::ChildStdout {
let handle = sys::handle::Handle::from_inner(handle);
let pipe = sys::pipe::AnonPipe::from_inner(handle);
process::ChildStdout::from_inner(pipe)
}
}
/// Create a `ChildStderr` from the provided `OwnedHandle`.
///
/// The provided handle must be asynchronous, as reading and
/// writing from and to it is implemented using asynchronous APIs.
#[stable(feature = "child_stream_from_fd", since = "CURRENT_RUSTC_VERSION")]
impl From<OwnedHandle> for process::ChildStderr {
fn from(handle: OwnedHandle) -> process::ChildStderr {
let handle = sys::handle::Handle::from_inner(handle);
let pipe = sys::pipe::AnonPipe::from_inner(handle);
process::ChildStderr::from_inner(pipe)
}
}
/// Windows-specific extensions to [`process::ExitStatus`].
///
/// 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 = "exit_status_from", since = "1.12.0")]
pub trait ExitStatusExt: Sealed {
/// Creates a new `ExitStatus` from the raw underlying `u32` return value of
/// a process.
#[stable(feature = "exit_status_from", since = "1.12.0")]
fn from_raw(raw: u32) -> Self;
}
#[stable(feature = "exit_status_from", since = "1.12.0")]
impl ExitStatusExt for process::ExitStatus {
fn from_raw(raw: u32) -> Self {
process::ExitStatus::from_inner(From::from(raw))
}
}
/// Windows-specific extensions to the [`process::Command`] builder.
///
/// 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 = "windows_process_extensions", since = "1.16.0")]
pub trait CommandExt: Sealed {
/// Sets the [process creation flags][1] to be passed to `CreateProcess`.
///
/// These will always be ORed with `CREATE_UNICODE_ENVIRONMENT`.
///
/// [1]: https://docs.microsoft.com/en-us/windows/win32/procthread/process-creation-flags
#[stable(feature = "windows_process_extensions", since = "1.16.0")]
fn creation_flags(&mut self, flags: u32) -> &mut process::Command;
/// Forces all arguments to be wrapped in quote (`"`) characters.
///
/// This is useful for passing arguments to [MSYS2/Cygwin][1] based
/// executables: these programs will expand unquoted arguments containing
/// wildcard characters (`?` and `*`) by searching for any file paths
/// matching the wildcard pattern.
///
/// Adding quotes has no effect when passing arguments to programs
/// that use [msvcrt][2]. This includes programs built with both
/// MinGW and MSVC.
///
/// [1]: <https://github.com/msys2/MSYS2-packages/issues/2176>
/// [2]: <https://msdn.microsoft.com/en-us/library/17w5ykft.aspx>
#[unstable(feature = "windows_process_extensions_force_quotes", issue = "82227")]
fn force_quotes(&mut self, enabled: bool) -> &mut process::Command;
/// Append literal text to the command line without any quoting or escaping.
///
/// This is useful for passing arguments to `cmd.exe /c`, which doesn't follow
/// `CommandLineToArgvW` escaping rules.
#[stable(feature = "windows_process_extensions_raw_arg", since = "1.62.0")]
fn raw_arg<S: AsRef<OsStr>>(&mut self, text_to_append_as_is: S) -> &mut process::Command;
/// When [`process::Command`] creates pipes, request that our side is always async.
///
/// By default [`process::Command`] may choose to use pipes where both ends
/// are opened for synchronous read or write operations. By using
/// `async_pipes(true)`, this behavior is overridden so that our side is
/// always async.
///
/// This is important because if doing async I/O a pipe or a file has to be
/// opened for async access.
///
/// The end of the pipe sent to the child process will always be synchronous
/// regardless of this option.
///
/// # Example
///
/// ```
/// #![feature(windows_process_extensions_async_pipes)]
/// use std::os::windows::process::CommandExt;
/// use std::process::{Command, Stdio};
///
/// # let program = "";
///
/// Command::new(program)
/// .async_pipes(true)
/// .stdin(Stdio::piped())
/// .stdout(Stdio::piped())
/// .stderr(Stdio::piped());
/// ```
#[unstable(feature = "windows_process_extensions_async_pipes", issue = "98289")]
fn async_pipes(&mut self, always_async: bool) -> &mut process::Command;
/// Sets a raw attribute on the command, providing extended configuration options for Windows processes.
///
/// This method allows you to specify custom attributes for a child process on Windows systems using raw attribute values.
/// Raw attributes provide extended configurability for process creation, but their usage can be complex and potentially unsafe.
///
/// The `attribute` parameter specifies the raw attribute to be set, while the `value` parameter holds the value associated with that attribute.
/// Please refer to the [`windows-rs`](https://microsoft.github.io/windows-docs-rs/doc/windows/) documentation or the [`Win32 API documentation`](https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-updateprocthreadattribute) for detailed information about available attributes and their meanings.
///
/// # Note
///
/// The maximum number of raw attributes is the value of [`u32::MAX`].
/// If this limit is exceeded, the call to [`process::Command::spawn`] will return an `Error` indicating that the maximum number of attributes has been exceeded.
/// # Safety
///
/// The usage of raw attributes is potentially unsafe and should be done with caution. Incorrect attribute values or improper configuration can lead to unexpected behavior or errors.
///
/// # Example
///
/// The following example demonstrates how to create a child process with a specific parent process ID using a raw attribute.
///
/// ```rust
/// #![feature(windows_process_extensions_raw_attribute)]
/// use std::os::windows::{process::CommandExt, io::AsRawHandle};
/// use std::process::Command;
///
/// # struct ProcessDropGuard(std::process::Child);
/// # impl Drop for ProcessDropGuard {
/// # fn drop(&mut self) {
/// # let _ = self.0.kill();
/// # }
/// # }
///
/// let parent = Command::new("cmd").spawn()?;
///
/// let mut child_cmd = Command::new("cmd");
///
/// const PROC_THREAD_ATTRIBUTE_PARENT_PROCESS: usize = 0x00020000;
///
/// unsafe {
/// child_cmd.raw_attribute(PROC_THREAD_ATTRIBUTE_PARENT_PROCESS, parent.as_raw_handle() as isize);
/// }
/// #
/// # let parent = ProcessDropGuard(parent);
///
/// let mut child = child_cmd.spawn()?;
///
/// # child.kill()?;
/// # Ok::<(), std::io::Error>(())
/// ```
///
/// # Safety Note
///
/// Remember that improper use of raw attributes can lead to undefined behavior or security vulnerabilities. Always consult the documentation and ensure proper attribute values are used.
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
unsafe fn raw_attribute<T: Copy + Send + Sync + 'static>(
&mut self,
attribute: usize,
value: T,
) -> &mut process::Command;
}
#[stable(feature = "windows_process_extensions", since = "1.16.0")]
impl CommandExt for process::Command {
fn creation_flags(&mut self, flags: u32) -> &mut process::Command {
self.as_inner_mut().creation_flags(flags);
self
}
fn force_quotes(&mut self, enabled: bool) -> &mut process::Command {
self.as_inner_mut().force_quotes(enabled);
self
}
fn raw_arg<S: AsRef<OsStr>>(&mut self, raw_text: S) -> &mut process::Command {
self.as_inner_mut().raw_arg(raw_text.as_ref());
self
}
fn async_pipes(&mut self, always_async: bool) -> &mut process::Command {
// FIXME: This currently has an intentional no-op implementation.
// For the time being our side of the pipes will always be async.
// Once the ecosystem has adjusted, we may then be able to start making
// use of synchronous pipes within the standard library.
let _ = always_async;
self
}
unsafe fn raw_attribute<T: Copy + Send + Sync + 'static>(
&mut self,
attribute: usize,
value: T,
) -> &mut process::Command {
self.as_inner_mut().raw_attribute(attribute, value);
self
}
}
#[unstable(feature = "windows_process_extensions_main_thread_handle", issue = "96723")]
pub trait ChildExt: Sealed {
/// Extracts the main thread raw handle, without taking ownership
#[unstable(feature = "windows_process_extensions_main_thread_handle", issue = "96723")]
fn main_thread_handle(&self) -> BorrowedHandle<'_>;
}
#[unstable(feature = "windows_process_extensions_main_thread_handle", issue = "96723")]
impl ChildExt for process::Child {
fn main_thread_handle(&self) -> BorrowedHandle<'_> {
self.handle.main_thread_handle()
}
}
/// Windows-specific extensions to [`process::ExitCode`].
///
/// This trait is sealed: it cannot be implemented outside the standard library.
/// This is so that future additional methods are not breaking changes.
#[unstable(feature = "windows_process_exit_code_from", issue = "none")]
pub trait ExitCodeExt: Sealed {
/// Creates a new `ExitCode` from the raw underlying `u32` return value of
/// a process.
///
/// The exit code should not be 259, as this conflicts with the `STILL_ACTIVE`
/// macro returned from the `GetExitCodeProcess` function to signal that the
/// process has yet to run to completion.
#[unstable(feature = "windows_process_exit_code_from", issue = "none")]
fn from_raw(raw: u32) -> Self;
}
#[unstable(feature = "windows_process_exit_code_from", issue = "none")]
impl ExitCodeExt for process::ExitCode {
fn from_raw(raw: u32) -> Self {
process::ExitCode::from_inner(From::from(raw))
}
}