std/os/windows/process.rs
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//! 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, c_void};
use crate::mem::MaybeUninit;
use crate::os::windows::io::{
AsHandle, AsRawHandle, BorrowedHandle, FromRawHandle, IntoRawHandle, OwnedHandle, RawHandle,
};
use crate::sealed::Sealed;
use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
use crate::{io, marker, process, ptr, sys};
#[stable(feature = "process_extensions", since = "1.2.0")]
impl FromRawHandle for process::Stdio {
unsafe fn from_raw_handle(handle: RawHandle) -> process::Stdio {
let handle = unsafe { 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 {
/// Takes ownership of a handle and returns a [`Stdio`](process::Stdio)
/// that can attach a stream to it.
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 {
/// Takes ownership of a [`Child`](process::Child)'s process handle.
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 _
}
}
/// Creates 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 = "1.74.0")]
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)
}
}
/// Creates 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 = "1.74.0")]
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)
}
}
/// Creates 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 = "1.74.0")]
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;
/// Sets the field `wShowWindow` of [STARTUPINFO][1] that is passed to `CreateProcess`.
/// Allowed values are the ones listed in
/// <https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-showwindow>
///
/// [1]: <https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/ns-processthreadsapi-startupinfow>
#[unstable(feature = "windows_process_extensions_show_window", issue = "127544")]
fn show_window(&mut self, cmd_show: u16) -> &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 applications that don't follow
/// the standard C run-time escaping rules, such as `cmd.exe /c`.
///
/// # Batch files
///
/// Note the `cmd /c` command line has slightly different escaping rules than batch files
/// themselves. If possible, it may be better to write complex arguments to a temporary
/// `.bat` file, with appropriate escaping, and simply run that using:
///
/// ```no_run
/// # use std::process::Command;
/// # let temp_bat_file = "";
/// # #[allow(unused)]
/// let output = Command::new("cmd").args(["/c", &format!("\"{temp_bat_file}\"")]).output();
/// ```
///
/// # Example
///
/// Run a batch script using both trusted and untrusted arguments.
///
/// ```no_run
/// #[cfg(windows)]
/// // `my_script_path` is a path to known bat file.
/// // `user_name` is an untrusted name given by the user.
/// fn run_script(
/// my_script_path: &str,
/// user_name: &str,
/// ) -> Result<std::process::Output, std::io::Error> {
/// use std::io::{Error, ErrorKind};
/// use std::os::windows::process::CommandExt;
/// use std::process::Command;
///
/// // Create the command line, making sure to quote the script path.
/// // This assumes the fixed arguments have been tested to work with the script we're using.
/// let mut cmd_args = format!(r#""{my_script_path}" "--features=[a,b,c]""#);
///
/// // Make sure the user name is safe. In particular we need to be
/// // cautious of ascii symbols that cmd may interpret specially.
/// // Here we only allow alphanumeric characters.
/// if !user_name.chars().all(|c| c.is_alphanumeric()) {
/// return Err(Error::new(ErrorKind::InvalidInput, "invalid user name"));
/// }
///
/// // now we have validated the user name, let's add that too.
/// cmd_args.push_str(" --user ");
/// cmd_args.push_str(user_name);
///
/// // call cmd.exe and return the output
/// Command::new("cmd.exe")
/// .arg("/c")
/// // surround the entire command in an extra pair of quotes, as required by cmd.exe.
/// .raw_arg(&format!("\"{cmd_args}\""))
/// .output()
/// }
/// ````
#[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;
/// Executes the command as a child process with the given
/// [`ProcThreadAttributeList`], returning a handle to it.
///
/// This method enables the customization of attributes for the spawned
/// child process on Windows systems.
/// Attributes offer extended configurability for process creation,
/// but their usage can be intricate and potentially unsafe.
///
/// # Note
///
/// By default, stdin, stdout, and stderr are inherited from the parent
/// process.
///
/// # Example
///
/// ```
/// #![feature(windows_process_extensions_raw_attribute)]
/// use std::os::windows::io::AsRawHandle;
/// use std::os::windows::process::{CommandExt, ProcThreadAttributeList};
/// 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 parent_process_handle = parent.as_raw_handle();
/// # let parent = ProcessDropGuard(parent);
///
/// const PROC_THREAD_ATTRIBUTE_PARENT_PROCESS: usize = 0x00020000;
/// let mut attribute_list = ProcThreadAttributeList::build()
/// .attribute(PROC_THREAD_ATTRIBUTE_PARENT_PROCESS, &parent_process_handle)
/// .finish()
/// .unwrap();
///
/// let mut child = Command::new("cmd").spawn_with_attributes(&attribute_list)?;
/// #
/// # child.kill()?;
/// # Ok::<(), std::io::Error>(())
/// ```
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
fn spawn_with_attributes(
&mut self,
attribute_list: &ProcThreadAttributeList<'_>,
) -> io::Result<process::Child>;
}
#[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 show_window(&mut self, cmd_show: u16) -> &mut process::Command {
self.as_inner_mut().show_window(Some(cmd_show));
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
}
fn spawn_with_attributes(
&mut self,
attribute_list: &ProcThreadAttributeList<'_>,
) -> io::Result<process::Child> {
self.as_inner_mut()
.spawn_with_attributes(sys::process::Stdio::Inherit, true, Some(attribute_list))
.map(process::Child::from_inner)
}
}
#[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 = "111688")]
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 = "111688")]
fn from_raw(raw: u32) -> Self;
}
#[unstable(feature = "windows_process_exit_code_from", issue = "111688")]
impl ExitCodeExt for process::ExitCode {
fn from_raw(raw: u32) -> Self {
process::ExitCode::from_inner(From::from(raw))
}
}
/// A wrapper around windows [`ProcThreadAttributeList`][1].
///
/// [1]: <https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-initializeprocthreadattributelist>
#[derive(Debug)]
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
pub struct ProcThreadAttributeList<'a> {
attribute_list: Box<[MaybeUninit<u8>]>,
_lifetime_marker: marker::PhantomData<&'a ()>,
}
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
impl<'a> ProcThreadAttributeList<'a> {
/// Creates a new builder for constructing a [`ProcThreadAttributeList`].
pub fn build() -> ProcThreadAttributeListBuilder<'a> {
ProcThreadAttributeListBuilder::new()
}
/// Returns a pointer to the underling attribute list.
#[doc(hidden)]
pub fn as_ptr(&self) -> *const MaybeUninit<u8> {
self.attribute_list.as_ptr()
}
}
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
impl<'a> Drop for ProcThreadAttributeList<'a> {
/// Deletes the attribute list.
///
/// This method calls [`DeleteProcThreadAttributeList`][1] to delete the
/// underlying attribute list.
///
/// [1]: <https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-deleteprocthreadattributelist>
fn drop(&mut self) {
let lp_attribute_list = self.attribute_list.as_mut_ptr().cast::<c_void>();
unsafe { sys::c::DeleteProcThreadAttributeList(lp_attribute_list) }
}
}
/// Builder for constructing a [`ProcThreadAttributeList`].
#[derive(Clone, Debug)]
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
pub struct ProcThreadAttributeListBuilder<'a> {
attributes: alloc::collections::BTreeMap<usize, ProcThreadAttributeValue>,
_lifetime_marker: marker::PhantomData<&'a ()>,
}
#[unstable(feature = "windows_process_extensions_raw_attribute", issue = "114854")]
impl<'a> ProcThreadAttributeListBuilder<'a> {
fn new() -> Self {
ProcThreadAttributeListBuilder {
attributes: alloc::collections::BTreeMap::new(),
_lifetime_marker: marker::PhantomData,
}
}
/// Sets an attribute on the attribute list.
///
/// 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 documentation][1] for a list of valid attributes.
///
/// # Note
///
/// The maximum number of attributes is the value of [`u32::MAX`]. If this
/// limit is exceeded, the call to [`Self::finish`] will return an `Error`
/// indicating that the maximum number of attributes has been exceeded.
///
/// # Safety Note
///
/// Remember that improper use of attributes can lead to undefined behavior
/// or security vulnerabilities. Always consult the documentation and ensure
/// proper attribute values are used.
///
/// [1]: <https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-updateprocthreadattribute#parameters>
pub fn attribute<T>(self, attribute: usize, value: &'a T) -> Self {
unsafe {
self.raw_attribute(
attribute,
ptr::addr_of!(*value).cast::<c_void>(),
crate::mem::size_of::<T>(),
)
}
}
/// Sets a raw attribute on the attribute list.
///
/// This function is useful for setting attributes with pointers or sizes
/// that cannot be derived directly from their values.
///
/// # Safety
///
/// This function is marked as `unsafe` because it deals with raw pointers
/// and sizes. It is the responsibility of the caller to ensure the value
/// lives longer than the resulting [`ProcThreadAttributeList`] as well as
/// the validity of the size parameter.
///
/// # Example
///
/// ```
/// #![feature(windows_process_extensions_raw_attribute)]
/// use std::ffi::c_void;
/// use std::os::windows::process::{CommandExt, ProcThreadAttributeList};
/// use std::os::windows::raw::HANDLE;
/// use std::process::Command;
///
/// #[repr(C)]
/// pub struct COORD {
/// pub X: i16,
/// pub Y: i16,
/// }
///
/// extern "system" {
/// fn CreatePipe(
/// hreadpipe: *mut HANDLE,
/// hwritepipe: *mut HANDLE,
/// lppipeattributes: *const c_void,
/// nsize: u32,
/// ) -> i32;
/// fn CreatePseudoConsole(
/// size: COORD,
/// hinput: HANDLE,
/// houtput: HANDLE,
/// dwflags: u32,
/// phpc: *mut isize,
/// ) -> i32;
/// fn CloseHandle(hobject: HANDLE) -> i32;
/// }
///
/// let [mut input_read_side, mut output_write_side, mut output_read_side, mut input_write_side] =
/// [unsafe { std::mem::zeroed::<HANDLE>() }; 4];
///
/// unsafe {
/// CreatePipe(&mut input_read_side, &mut input_write_side, std::ptr::null(), 0);
/// CreatePipe(&mut output_read_side, &mut output_write_side, std::ptr::null(), 0);
/// }
///
/// let size = COORD { X: 60, Y: 40 };
/// let mut h_pc = unsafe { std::mem::zeroed() };
/// unsafe { CreatePseudoConsole(size, input_read_side, output_write_side, 0, &mut h_pc) };
///
/// unsafe { CloseHandle(input_read_side) };
/// unsafe { CloseHandle(output_write_side) };
///
/// const PROC_THREAD_ATTRIBUTE_PSEUDOCONSOLE: usize = 131094;
///
/// let attribute_list = unsafe {
/// ProcThreadAttributeList::build()
/// .raw_attribute(
/// PROC_THREAD_ATTRIBUTE_PSEUDOCONSOLE,
/// h_pc as *const c_void,
/// std::mem::size_of::<isize>(),
/// )
/// .finish()?
/// };
///
/// let mut child = Command::new("cmd").spawn_with_attributes(&attribute_list)?;
/// #
/// # child.kill()?;
/// # Ok::<(), std::io::Error>(())
/// ```
pub unsafe fn raw_attribute<T>(
mut self,
attribute: usize,
value_ptr: *const T,
value_size: usize,
) -> Self {
self.attributes.insert(
attribute,
ProcThreadAttributeValue { ptr: value_ptr.cast::<c_void>(), size: value_size },
);
self
}
/// Finalizes the construction of the `ProcThreadAttributeList`.
///
/// # Errors
///
/// Returns an error if the maximum number of attributes is exceeded
/// or if there is an I/O error during initialization.
pub fn finish(&self) -> io::Result<ProcThreadAttributeList<'a>> {
// To initialize our ProcThreadAttributeList, we need to determine
// how many bytes to allocate for it. The Windows API simplifies this
// process by allowing us to call `InitializeProcThreadAttributeList`
// with a null pointer to retrieve the required size.
let mut required_size = 0;
let Ok(attribute_count) = self.attributes.len().try_into() else {
return Err(io::const_error!(
io::ErrorKind::InvalidInput,
"maximum number of ProcThreadAttributes exceeded",
));
};
unsafe {
sys::c::InitializeProcThreadAttributeList(
ptr::null_mut(),
attribute_count,
0,
&mut required_size,
)
};
let mut attribute_list = vec![MaybeUninit::uninit(); required_size].into_boxed_slice();
// Once we've allocated the necessary memory, it's safe to invoke
// `InitializeProcThreadAttributeList` to properly initialize the list.
sys::cvt(unsafe {
sys::c::InitializeProcThreadAttributeList(
attribute_list.as_mut_ptr().cast::<c_void>(),
attribute_count,
0,
&mut required_size,
)
})?;
// # Add our attributes to the buffer.
// It's theoretically possible for the attribute count to exceed a u32
// value. Therefore, we ensure that we don't add more attributes than
// the buffer was initialized for.
for (&attribute, value) in self.attributes.iter().take(attribute_count as usize) {
sys::cvt(unsafe {
sys::c::UpdateProcThreadAttribute(
attribute_list.as_mut_ptr().cast::<c_void>(),
0,
attribute,
value.ptr,
value.size,
ptr::null_mut(),
ptr::null_mut(),
)
})?;
}
Ok(ProcThreadAttributeList { attribute_list, _lifetime_marker: marker::PhantomData })
}
}
/// Wrapper around the value data to be used as a Process Thread Attribute.
#[derive(Clone, Debug)]
struct ProcThreadAttributeValue {
ptr: *const c_void,
size: usize,
}