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Diffstat (limited to 'library/std/src/process.rs')
| -rw-r--r-- | library/std/src/process.rs | 2112 |
1 files changed, 2112 insertions, 0 deletions
diff --git a/library/std/src/process.rs b/library/std/src/process.rs new file mode 100644 index 00000000000..4ba1940fd0e --- /dev/null +++ b/library/std/src/process.rs @@ -0,0 +1,2112 @@ +//! A module for working with processes. +//! +//! This module is mostly concerned with spawning and interacting with child +//! processes, but it also provides [`abort`] and [`exit`] for terminating the +//! current process. +//! +//! # Spawning a process +//! +//! The [`Command`] struct is used to configure and spawn processes: +//! +//! ```no_run +//! use std::process::Command; +//! +//! let output = Command::new("echo") +//! .arg("Hello world") +//! .output() +//! .expect("Failed to execute command"); +//! +//! assert_eq!(b"Hello world\n", output.stdout.as_slice()); +//! ``` +//! +//! Several methods on [`Command`], such as [`spawn`] or [`output`], can be used +//! to spawn a process. In particular, [`output`] spawns the child process and +//! waits until the process terminates, while [`spawn`] will return a [`Child`] +//! that represents the spawned child process. +//! +//! # Handling I/O +//! +//! The [`stdout`], [`stdin`], and [`stderr`] of a child process can be +//! configured by passing an [`Stdio`] to the corresponding method on +//! [`Command`]. Once spawned, they can be accessed from the [`Child`]. For +//! example, piping output from one command into another command can be done +//! like so: +//! +//! ```no_run +//! use std::process::{Command, Stdio}; +//! +//! // stdout must be configured with `Stdio::piped` in order to use +//! // `echo_child.stdout` +//! let echo_child = Command::new("echo") +//! .arg("Oh no, a tpyo!") +//! .stdout(Stdio::piped()) +//! .spawn() +//! .expect("Failed to start echo process"); +//! +//! // Note that `echo_child` is moved here, but we won't be needing +//! // `echo_child` anymore +//! let echo_out = echo_child.stdout.expect("Failed to open echo stdout"); +//! +//! let mut sed_child = Command::new("sed") +//! .arg("s/tpyo/typo/") +//! .stdin(Stdio::from(echo_out)) +//! .stdout(Stdio::piped()) +//! .spawn() +//! .expect("Failed to start sed process"); +//! +//! let output = sed_child.wait_with_output().expect("Failed to wait on sed"); +//! assert_eq!(b"Oh no, a typo!\n", output.stdout.as_slice()); +//! ``` +//! +//! Note that [`ChildStderr`] and [`ChildStdout`] implement [`Read`] and +//! [`ChildStdin`] implements [`Write`]: +//! +//! ```no_run +//! use std::process::{Command, Stdio}; +//! use std::io::Write; +//! +//! let mut child = Command::new("/bin/cat") +//! .stdin(Stdio::piped()) +//! .stdout(Stdio::piped()) +//! .spawn() +//! .expect("failed to execute child"); +//! +//! { +//! // limited borrow of stdin +//! let stdin = child.stdin.as_mut().expect("failed to get stdin"); +//! stdin.write_all(b"test").expect("failed to write to stdin"); +//! } +//! +//! let output = child +//! .wait_with_output() +//! .expect("failed to wait on child"); +//! +//! assert_eq!(b"test", output.stdout.as_slice()); +//! ``` +//! +//! [`abort`]: fn.abort.html +//! [`exit`]: fn.exit.html +//! +//! [`Command`]: struct.Command.html +//! [`spawn`]: struct.Command.html#method.spawn +//! [`output`]: struct.Command.html#method.output +//! +//! [`Child`]: struct.Child.html +//! [`ChildStdin`]: struct.ChildStdin.html +//! [`ChildStdout`]: struct.ChildStdout.html +//! [`ChildStderr`]: struct.ChildStderr.html +//! [`Stdio`]: struct.Stdio.html +//! +//! [`stdout`]: struct.Command.html#method.stdout +//! [`stdin`]: struct.Command.html#method.stdin +//! [`stderr`]: struct.Command.html#method.stderr +//! +//! [`Write`]: ../io/trait.Write.html +//! [`Read`]: ../io/trait.Read.html + +#![stable(feature = "process", since = "1.0.0")] + +use crate::io::prelude::*; + +use crate::ffi::OsStr; +use crate::fmt; +use crate::fs; +use crate::io::{self, Initializer, IoSlice, IoSliceMut}; +use crate::path::Path; +use crate::str; +use crate::sys::pipe::{read2, AnonPipe}; +use crate::sys::process as imp; +use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner}; + +/// Representation of a running or exited child process. +/// +/// This structure is used to represent and manage child processes. A child +/// process is created via the [`Command`] struct, which configures the +/// spawning process and can itself be constructed using a builder-style +/// interface. +/// +/// There is no implementation of [`Drop`] for child processes, +/// so if you do not ensure the `Child` has exited then it will continue to +/// run, even after the `Child` handle to the child process has gone out of +/// scope. +/// +/// Calling [`wait`](#method.wait) (or other functions that wrap around it) will make +/// the parent process wait until the child has actually exited before +/// continuing. +/// +/// # Warning +/// +/// On some system, calling [`wait`] or similar is necessary for the OS to +/// release resources. A process that terminated but has not been waited on is +/// still around as a "zombie". Leaving too many zombies around may exhaust +/// global resources (for example process IDs). +/// +/// The standard library does *not* automatically wait on child processes (not +/// even if the `Child` is dropped), it is up to the application developer to do +/// so. As a consequence, dropping `Child` handles without waiting on them first +/// is not recommended in long-running applications. +/// +/// # Examples +/// +/// ```should_panic +/// use std::process::Command; +/// +/// let mut child = Command::new("/bin/cat") +/// .arg("file.txt") +/// .spawn() +/// .expect("failed to execute child"); +/// +/// let ecode = child.wait() +/// .expect("failed to wait on child"); +/// +/// assert!(ecode.success()); +/// ``` +/// +/// [`Command`]: struct.Command.html +/// [`Drop`]: ../../core/ops/trait.Drop.html +/// [`wait`]: #method.wait +#[stable(feature = "process", since = "1.0.0")] +pub struct Child { + handle: imp::Process, + + /// The handle for writing to the child's standard input (stdin), if it has + /// been captured. + #[stable(feature = "process", since = "1.0.0")] + pub stdin: Option<ChildStdin>, + + /// The handle for reading from the child's standard output (stdout), if it + /// has been captured. + #[stable(feature = "process", since = "1.0.0")] + pub stdout: Option<ChildStdout>, + + /// The handle for reading from the child's standard error (stderr), if it + /// has been captured. + #[stable(feature = "process", since = "1.0.0")] + pub stderr: Option<ChildStderr>, +} + +impl AsInner<imp::Process> for Child { + fn as_inner(&self) -> &imp::Process { + &self.handle + } +} + +impl FromInner<(imp::Process, imp::StdioPipes)> for Child { + fn from_inner((handle, io): (imp::Process, imp::StdioPipes)) -> Child { + Child { + handle, + stdin: io.stdin.map(ChildStdin::from_inner), + stdout: io.stdout.map(ChildStdout::from_inner), + stderr: io.stderr.map(ChildStderr::from_inner), + } + } +} + +impl IntoInner<imp::Process> for Child { + fn into_inner(self) -> imp::Process { + self.handle + } +} + +#[stable(feature = "std_debug", since = "1.16.0")] +impl fmt::Debug for Child { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("Child") + .field("stdin", &self.stdin) + .field("stdout", &self.stdout) + .field("stderr", &self.stderr) + .finish() + } +} + +/// A handle to a child process's standard input (stdin). +/// +/// This struct is used in the [`stdin`] field on [`Child`]. +/// +/// When an instance of `ChildStdin` is [dropped], the `ChildStdin`'s underlying +/// file handle will be closed. If the child process was blocked on input prior +/// to being dropped, it will become unblocked after dropping. +/// +/// [`Child`]: struct.Child.html +/// [`stdin`]: struct.Child.html#structfield.stdin +/// [dropped]: ../ops/trait.Drop.html +#[stable(feature = "process", since = "1.0.0")] +pub struct ChildStdin { + inner: AnonPipe, +} + +#[stable(feature = "process", since = "1.0.0")] +impl Write for ChildStdin { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + self.inner.write(buf) + } + + fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> { + self.inner.write_vectored(bufs) + } + + fn is_write_vectored(&self) -> bool { + self.inner.is_write_vectored() + } + + fn flush(&mut self) -> io::Result<()> { + Ok(()) + } +} + +impl AsInner<AnonPipe> for ChildStdin { + fn as_inner(&self) -> &AnonPipe { + &self.inner + } +} + +impl IntoInner<AnonPipe> for ChildStdin { + fn into_inner(self) -> AnonPipe { + self.inner + } +} + +impl FromInner<AnonPipe> for ChildStdin { + fn from_inner(pipe: AnonPipe) -> ChildStdin { + ChildStdin { inner: pipe } + } +} + +#[stable(feature = "std_debug", since = "1.16.0")] +impl fmt::Debug for ChildStdin { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.pad("ChildStdin { .. }") + } +} + +/// A handle to a child process's standard output (stdout). +/// +/// This struct is used in the [`stdout`] field on [`Child`]. +/// +/// When an instance of `ChildStdout` is [dropped], the `ChildStdout`'s +/// underlying file handle will be closed. +/// +/// [`Child`]: struct.Child.html +/// [`stdout`]: struct.Child.html#structfield.stdout +/// [dropped]: ../ops/trait.Drop.html +#[stable(feature = "process", since = "1.0.0")] +pub struct ChildStdout { + inner: AnonPipe, +} + +#[stable(feature = "process", since = "1.0.0")] +impl Read for ChildStdout { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.inner.read(buf) + } + + fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> { + self.inner.read_vectored(bufs) + } + + #[inline] + fn is_read_vectored(&self) -> bool { + self.inner.is_read_vectored() + } + + #[inline] + unsafe fn initializer(&self) -> Initializer { + Initializer::nop() + } +} + +impl AsInner<AnonPipe> for ChildStdout { + fn as_inner(&self) -> &AnonPipe { + &self.inner + } +} + +impl IntoInner<AnonPipe> for ChildStdout { + fn into_inner(self) -> AnonPipe { + self.inner + } +} + +impl FromInner<AnonPipe> for ChildStdout { + fn from_inner(pipe: AnonPipe) -> ChildStdout { + ChildStdout { inner: pipe } + } +} + +#[stable(feature = "std_debug", since = "1.16.0")] +impl fmt::Debug for ChildStdout { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.pad("ChildStdout { .. }") + } +} + +/// A handle to a child process's stderr. +/// +/// This struct is used in the [`stderr`] field on [`Child`]. +/// +/// When an instance of `ChildStderr` is [dropped], the `ChildStderr`'s +/// underlying file handle will be closed. +/// +/// [`Child`]: struct.Child.html +/// [`stderr`]: struct.Child.html#structfield.stderr +/// [dropped]: ../ops/trait.Drop.html +#[stable(feature = "process", since = "1.0.0")] +pub struct ChildStderr { + inner: AnonPipe, +} + +#[stable(feature = "process", since = "1.0.0")] +impl Read for ChildStderr { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.inner.read(buf) + } + + fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> { + self.inner.read_vectored(bufs) + } + + #[inline] + fn is_read_vectored(&self) -> bool { + self.inner.is_read_vectored() + } + + #[inline] + unsafe fn initializer(&self) -> Initializer { + Initializer::nop() + } +} + +impl AsInner<AnonPipe> for ChildStderr { + fn as_inner(&self) -> &AnonPipe { + &self.inner + } +} + +impl IntoInner<AnonPipe> for ChildStderr { + fn into_inner(self) -> AnonPipe { + self.inner + } +} + +impl FromInner<AnonPipe> for ChildStderr { + fn from_inner(pipe: AnonPipe) -> ChildStderr { + ChildStderr { inner: pipe } + } +} + +#[stable(feature = "std_debug", since = "1.16.0")] +impl fmt::Debug for ChildStderr { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.pad("ChildStderr { .. }") + } +} + +/// A process builder, providing fine-grained control +/// over how a new process should be spawned. +/// +/// A default configuration can be +/// generated using `Command::new(program)`, where `program` gives a path to the +/// program to be executed. Additional builder methods allow the configuration +/// to be changed (for example, by adding arguments) prior to spawning: +/// +/// ``` +/// use std::process::Command; +/// +/// let output = if cfg!(target_os = "windows") { +/// Command::new("cmd") +/// .args(&["/C", "echo hello"]) +/// .output() +/// .expect("failed to execute process") +/// } else { +/// Command::new("sh") +/// .arg("-c") +/// .arg("echo hello") +/// .output() +/// .expect("failed to execute process") +/// }; +/// +/// let hello = output.stdout; +/// ``` +/// +/// `Command` can be reused to spawn multiple processes. The builder methods +/// change the command without needing to immediately spawn the process. +/// +/// ```no_run +/// use std::process::Command; +/// +/// let mut echo_hello = Command::new("sh"); +/// echo_hello.arg("-c") +/// .arg("echo hello"); +/// let hello_1 = echo_hello.output().expect("failed to execute process"); +/// let hello_2 = echo_hello.output().expect("failed to execute process"); +/// ``` +/// +/// Similarly, you can call builder methods after spawning a process and then +/// spawn a new process with the modified settings. +/// +/// ```no_run +/// use std::process::Command; +/// +/// let mut list_dir = Command::new("ls"); +/// +/// // Execute `ls` in the current directory of the program. +/// list_dir.status().expect("process failed to execute"); +/// +/// println!(); +/// +/// // Change `ls` to execute in the root directory. +/// list_dir.current_dir("/"); +/// +/// // And then execute `ls` again but in the root directory. +/// list_dir.status().expect("process failed to execute"); +/// ``` +#[stable(feature = "process", since = "1.0.0")] +pub struct Command { + inner: imp::Command, +} + +impl Command { + /// Constructs a new `Command` for launching the program at + /// path `program`, with the following default configuration: + /// + /// * No arguments to the program + /// * Inherit the current process's environment + /// * Inherit the current process's working directory + /// * Inherit stdin/stdout/stderr for `spawn` or `status`, but create pipes for `output` + /// + /// Builder methods are provided to change these defaults and + /// otherwise configure the process. + /// + /// If `program` is not an absolute path, the `PATH` will be searched in + /// an OS-defined way. + /// + /// The search path to be used may be controlled by setting the + /// `PATH` environment variable on the Command, + /// but this has some implementation limitations on Windows + /// (see issue #37519). + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("sh") + /// .spawn() + /// .expect("sh command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn new<S: AsRef<OsStr>>(program: S) -> Command { + Command { inner: imp::Command::new(program.as_ref()) } + } + + /// Adds an argument to pass to the program. + /// + /// Only one argument can be passed per use. So instead of: + /// + /// ```no_run + /// # std::process::Command::new("sh") + /// .arg("-C /path/to/repo") + /// # ; + /// ``` + /// + /// usage would be: + /// + /// ```no_run + /// # std::process::Command::new("sh") + /// .arg("-C") + /// .arg("/path/to/repo") + /// # ; + /// ``` + /// + /// To pass multiple arguments see [`args`]. + /// + /// [`args`]: #method.args + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .arg("-l") + /// .arg("-a") + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn arg<S: AsRef<OsStr>>(&mut self, arg: S) -> &mut Command { + self.inner.arg(arg.as_ref()); + self + } + + /// Adds multiple arguments to pass to the program. + /// + /// To pass a single argument see [`arg`]. + /// + /// [`arg`]: #method.arg + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .args(&["-l", "-a"]) + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn args<I, S>(&mut self, args: I) -> &mut Command + where + I: IntoIterator<Item = S>, + S: AsRef<OsStr>, + { + for arg in args { + self.arg(arg.as_ref()); + } + self + } + + /// Inserts or updates an environment variable mapping. + /// + /// Note that environment variable names are case-insensitive (but case-preserving) on Windows, + /// and case-sensitive on all other platforms. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .env("PATH", "/bin") + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn env<K, V>(&mut self, key: K, val: V) -> &mut Command + where + K: AsRef<OsStr>, + V: AsRef<OsStr>, + { + self.inner.env_mut().set(key.as_ref(), val.as_ref()); + self + } + + /// Adds or updates multiple environment variable mappings. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// use std::env; + /// use std::collections::HashMap; + /// + /// let filtered_env : HashMap<String, String> = + /// env::vars().filter(|&(ref k, _)| + /// k == "TERM" || k == "TZ" || k == "LANG" || k == "PATH" + /// ).collect(); + /// + /// Command::new("printenv") + /// .stdin(Stdio::null()) + /// .stdout(Stdio::inherit()) + /// .env_clear() + /// .envs(&filtered_env) + /// .spawn() + /// .expect("printenv failed to start"); + /// ``` + #[stable(feature = "command_envs", since = "1.19.0")] + pub fn envs<I, K, V>(&mut self, vars: I) -> &mut Command + where + I: IntoIterator<Item = (K, V)>, + K: AsRef<OsStr>, + V: AsRef<OsStr>, + { + for (ref key, ref val) in vars { + self.inner.env_mut().set(key.as_ref(), val.as_ref()); + } + self + } + + /// Removes an environment variable mapping. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .env_remove("PATH") + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn env_remove<K: AsRef<OsStr>>(&mut self, key: K) -> &mut Command { + self.inner.env_mut().remove(key.as_ref()); + self + } + + /// Clears the entire environment map for the child process. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .env_clear() + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn env_clear(&mut self) -> &mut Command { + self.inner.env_mut().clear(); + self + } + + /// Sets the working directory for the child process. + /// + /// # Platform-specific behavior + /// + /// If the program path is relative (e.g., `"./script.sh"`), it's ambiguous + /// whether it should be interpreted relative to the parent's working + /// directory or relative to `current_dir`. The behavior in this case is + /// platform specific and unstable, and it's recommended to use + /// [`canonicalize`] to get an absolute program path instead. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .current_dir("/bin") + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + /// + /// [`canonicalize`]: ../fs/fn.canonicalize.html + #[stable(feature = "process", since = "1.0.0")] + pub fn current_dir<P: AsRef<Path>>(&mut self, dir: P) -> &mut Command { + self.inner.cwd(dir.as_ref().as_ref()); + self + } + + /// Configuration for the child process's standard input (stdin) handle. + /// + /// Defaults to [`inherit`] when used with `spawn` or `status`, and + /// defaults to [`piped`] when used with `output`. + /// + /// [`inherit`]: struct.Stdio.html#method.inherit + /// [`piped`]: struct.Stdio.html#method.piped + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// Command::new("ls") + /// .stdin(Stdio::null()) + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn stdin<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Command { + self.inner.stdin(cfg.into().0); + self + } + + /// Configuration for the child process's standard output (stdout) handle. + /// + /// Defaults to [`inherit`] when used with `spawn` or `status`, and + /// defaults to [`piped`] when used with `output`. + /// + /// [`inherit`]: struct.Stdio.html#method.inherit + /// [`piped`]: struct.Stdio.html#method.piped + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// Command::new("ls") + /// .stdout(Stdio::null()) + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn stdout<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Command { + self.inner.stdout(cfg.into().0); + self + } + + /// Configuration for the child process's standard error (stderr) handle. + /// + /// Defaults to [`inherit`] when used with `spawn` or `status`, and + /// defaults to [`piped`] when used with `output`. + /// + /// [`inherit`]: struct.Stdio.html#method.inherit + /// [`piped`]: struct.Stdio.html#method.piped + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// Command::new("ls") + /// .stderr(Stdio::null()) + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn stderr<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Command { + self.inner.stderr(cfg.into().0); + self + } + + /// Executes the command as a child process, returning a handle to it. + /// + /// By default, stdin, stdout and stderr are inherited from the parent. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// Command::new("ls") + /// .spawn() + /// .expect("ls command failed to start"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn spawn(&mut self) -> io::Result<Child> { + self.inner.spawn(imp::Stdio::Inherit, true).map(Child::from_inner) + } + + /// Executes the command as a child process, waiting for it to finish and + /// collecting all of its output. + /// + /// By default, stdout and stderr are captured (and used to provide the + /// resulting output). Stdin is not inherited from the parent and any + /// attempt by the child process to read from the stdin stream will result + /// in the stream immediately closing. + /// + /// # Examples + /// + /// ```should_panic + /// use std::process::Command; + /// use std::io::{self, Write}; + /// let output = Command::new("/bin/cat") + /// .arg("file.txt") + /// .output() + /// .expect("failed to execute process"); + /// + /// println!("status: {}", output.status); + /// io::stdout().write_all(&output.stdout).unwrap(); + /// io::stderr().write_all(&output.stderr).unwrap(); + /// + /// assert!(output.status.success()); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn output(&mut self) -> io::Result<Output> { + self.inner + .spawn(imp::Stdio::MakePipe, false) + .map(Child::from_inner) + .and_then(|p| p.wait_with_output()) + } + + /// Executes a command as a child process, waiting for it to finish and + /// collecting its exit status. + /// + /// By default, stdin, stdout and stderr are inherited from the parent. + /// + /// # Examples + /// + /// ```should_panic + /// use std::process::Command; + /// + /// let status = Command::new("/bin/cat") + /// .arg("file.txt") + /// .status() + /// .expect("failed to execute process"); + /// + /// println!("process exited with: {}", status); + /// + /// assert!(status.success()); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn status(&mut self) -> io::Result<ExitStatus> { + self.inner + .spawn(imp::Stdio::Inherit, true) + .map(Child::from_inner) + .and_then(|mut p| p.wait()) + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl fmt::Debug for Command { + /// Format the program and arguments of a Command for display. Any + /// non-utf8 data is lossily converted using the utf8 replacement + /// character. + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.inner.fmt(f) + } +} + +impl AsInner<imp::Command> for Command { + fn as_inner(&self) -> &imp::Command { + &self.inner + } +} + +impl AsInnerMut<imp::Command> for Command { + fn as_inner_mut(&mut self) -> &mut imp::Command { + &mut self.inner + } +} + +/// The output of a finished process. +/// +/// This is returned in a Result by either the [`output`] method of a +/// [`Command`], or the [`wait_with_output`] method of a [`Child`] +/// process. +/// +/// [`Command`]: struct.Command.html +/// [`Child`]: struct.Child.html +/// [`output`]: struct.Command.html#method.output +/// [`wait_with_output`]: struct.Child.html#method.wait_with_output +#[derive(PartialEq, Eq, Clone)] +#[stable(feature = "process", since = "1.0.0")] +pub struct Output { + /// The status (exit code) of the process. + #[stable(feature = "process", since = "1.0.0")] + pub status: ExitStatus, + /// The data that the process wrote to stdout. + #[stable(feature = "process", since = "1.0.0")] + pub stdout: Vec<u8>, + /// The data that the process wrote to stderr. + #[stable(feature = "process", since = "1.0.0")] + pub stderr: Vec<u8>, +} + +// If either stderr or stdout are valid utf8 strings it prints the valid +// strings, otherwise it prints the byte sequence instead +#[stable(feature = "process_output_debug", since = "1.7.0")] +impl fmt::Debug for Output { + fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { + let stdout_utf8 = str::from_utf8(&self.stdout); + let stdout_debug: &dyn fmt::Debug = match stdout_utf8 { + Ok(ref str) => str, + Err(_) => &self.stdout, + }; + + let stderr_utf8 = str::from_utf8(&self.stderr); + let stderr_debug: &dyn fmt::Debug = match stderr_utf8 { + Ok(ref str) => str, + Err(_) => &self.stderr, + }; + + fmt.debug_struct("Output") + .field("status", &self.status) + .field("stdout", stdout_debug) + .field("stderr", stderr_debug) + .finish() + } +} + +/// Describes what to do with a standard I/O stream for a child process when +/// passed to the [`stdin`], [`stdout`], and [`stderr`] methods of [`Command`]. +/// +/// [`stdin`]: struct.Command.html#method.stdin +/// [`stdout`]: struct.Command.html#method.stdout +/// [`stderr`]: struct.Command.html#method.stderr +/// [`Command`]: struct.Command.html +#[stable(feature = "process", since = "1.0.0")] +pub struct Stdio(imp::Stdio); + +impl Stdio { + /// A new pipe should be arranged to connect the parent and child processes. + /// + /// # Examples + /// + /// With stdout: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// let output = Command::new("echo") + /// .arg("Hello, world!") + /// .stdout(Stdio::piped()) + /// .output() + /// .expect("Failed to execute command"); + /// + /// assert_eq!(String::from_utf8_lossy(&output.stdout), "Hello, world!\n"); + /// // Nothing echoed to console + /// ``` + /// + /// With stdin: + /// + /// ```no_run + /// use std::io::Write; + /// use std::process::{Command, Stdio}; + /// + /// let mut child = Command::new("rev") + /// .stdin(Stdio::piped()) + /// .stdout(Stdio::piped()) + /// .spawn() + /// .expect("Failed to spawn child process"); + /// + /// { + /// let stdin = child.stdin.as_mut().expect("Failed to open stdin"); + /// stdin.write_all("Hello, world!".as_bytes()).expect("Failed to write to stdin"); + /// } + /// + /// let output = child.wait_with_output().expect("Failed to read stdout"); + /// assert_eq!(String::from_utf8_lossy(&output.stdout), "!dlrow ,olleH"); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn piped() -> Stdio { + Stdio(imp::Stdio::MakePipe) + } + + /// The child inherits from the corresponding parent descriptor. + /// + /// # Examples + /// + /// With stdout: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// let output = Command::new("echo") + /// .arg("Hello, world!") + /// .stdout(Stdio::inherit()) + /// .output() + /// .expect("Failed to execute command"); + /// + /// assert_eq!(String::from_utf8_lossy(&output.stdout), ""); + /// // "Hello, world!" echoed to console + /// ``` + /// + /// With stdin: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// use std::io::{self, Write}; + /// + /// let output = Command::new("rev") + /// .stdin(Stdio::inherit()) + /// .stdout(Stdio::piped()) + /// .output() + /// .expect("Failed to execute command"); + /// + /// print!("You piped in the reverse of: "); + /// io::stdout().write_all(&output.stdout).unwrap(); + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn inherit() -> Stdio { + Stdio(imp::Stdio::Inherit) + } + + /// This stream will be ignored. This is the equivalent of attaching the + /// stream to `/dev/null` + /// + /// # Examples + /// + /// With stdout: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// let output = Command::new("echo") + /// .arg("Hello, world!") + /// .stdout(Stdio::null()) + /// .output() + /// .expect("Failed to execute command"); + /// + /// assert_eq!(String::from_utf8_lossy(&output.stdout), ""); + /// // Nothing echoed to console + /// ``` + /// + /// With stdin: + /// + /// ```no_run + /// use std::process::{Command, Stdio}; + /// + /// let output = Command::new("rev") + /// .stdin(Stdio::null()) + /// .stdout(Stdio::piped()) + /// .output() + /// .expect("Failed to execute command"); + /// + /// assert_eq!(String::from_utf8_lossy(&output.stdout), ""); + /// // Ignores any piped-in input + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn null() -> Stdio { + Stdio(imp::Stdio::Null) + } +} + +impl FromInner<imp::Stdio> for Stdio { + fn from_inner(inner: imp::Stdio) -> Stdio { + Stdio(inner) + } +} + +#[stable(feature = "std_debug", since = "1.16.0")] +impl fmt::Debug for Stdio { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.pad("Stdio { .. }") + } +} + +#[stable(feature = "stdio_from", since = "1.20.0")] +impl From<ChildStdin> for Stdio { + /// Converts a `ChildStdin` into a `Stdio` + /// + /// # Examples + /// + /// `ChildStdin` will be converted to `Stdio` using `Stdio::from` under the hood. + /// + /// ```rust,no_run + /// use std::process::{Command, Stdio}; + /// + /// let reverse = Command::new("rev") + /// .stdin(Stdio::piped()) + /// .spawn() + /// .expect("failed reverse command"); + /// + /// let _echo = Command::new("echo") + /// .arg("Hello, world!") + /// .stdout(reverse.stdin.unwrap()) // Converted into a Stdio here + /// .output() + /// .expect("failed echo command"); + /// + /// // "!dlrow ,olleH" echoed to console + /// ``` + fn from(child: ChildStdin) -> Stdio { + Stdio::from_inner(child.into_inner().into()) + } +} + +#[stable(feature = "stdio_from", since = "1.20.0")] +impl From<ChildStdout> for Stdio { + /// Converts a `ChildStdout` into a `Stdio` + /// + /// # Examples + /// + /// `ChildStdout` will be converted to `Stdio` using `Stdio::from` under the hood. + /// + /// ```rust,no_run + /// use std::process::{Command, Stdio}; + /// + /// let hello = Command::new("echo") + /// .arg("Hello, world!") + /// .stdout(Stdio::piped()) + /// .spawn() + /// .expect("failed echo command"); + /// + /// let reverse = Command::new("rev") + /// .stdin(hello.stdout.unwrap()) // Converted into a Stdio here + /// .output() + /// .expect("failed reverse command"); + /// + /// assert_eq!(reverse.stdout, b"!dlrow ,olleH\n"); + /// ``` + fn from(child: ChildStdout) -> Stdio { + Stdio::from_inner(child.into_inner().into()) + } +} + +#[stable(feature = "stdio_from", since = "1.20.0")] +impl From<ChildStderr> for Stdio { + /// Converts a `ChildStderr` into a `Stdio` + /// + /// # Examples + /// + /// ```rust,no_run + /// use std::process::{Command, Stdio}; + /// + /// let reverse = Command::new("rev") + /// .arg("non_existing_file.txt") + /// .stderr(Stdio::piped()) + /// .spawn() + /// .expect("failed reverse command"); + /// + /// let cat = Command::new("cat") + /// .arg("-") + /// .stdin(reverse.stderr.unwrap()) // Converted into a Stdio here + /// .output() + /// .expect("failed echo command"); + /// + /// assert_eq!( + /// String::from_utf8_lossy(&cat.stdout), + /// "rev: cannot open non_existing_file.txt: No such file or directory\n" + /// ); + /// ``` + fn from(child: ChildStderr) -> Stdio { + Stdio::from_inner(child.into_inner().into()) + } +} + +#[stable(feature = "stdio_from", since = "1.20.0")] +impl From<fs::File> for Stdio { + /// Converts a `File` into a `Stdio` + /// + /// # Examples + /// + /// `File` will be converted to `Stdio` using `Stdio::from` under the hood. + /// + /// ```rust,no_run + /// use std::fs::File; + /// use std::process::Command; + /// + /// // With the `foo.txt` file containing `Hello, world!" + /// let file = File::open("foo.txt").unwrap(); + /// + /// let reverse = Command::new("rev") + /// .stdin(file) // Implicit File conversion into a Stdio + /// .output() + /// .expect("failed reverse command"); + /// + /// assert_eq!(reverse.stdout, b"!dlrow ,olleH"); + /// ``` + fn from(file: fs::File) -> Stdio { + Stdio::from_inner(file.into_inner().into()) + } +} + +/// Describes the result of a process after it has terminated. +/// +/// This `struct` is used to represent the exit status of a child process. +/// Child processes are created via the [`Command`] struct and their exit +/// status is exposed through the [`status`] method, or the [`wait`] method +/// of a [`Child`] process. +/// +/// [`Command`]: struct.Command.html +/// [`Child`]: struct.Child.html +/// [`status`]: struct.Command.html#method.status +/// [`wait`]: struct.Child.html#method.wait +#[derive(PartialEq, Eq, Clone, Copy, Debug)] +#[stable(feature = "process", since = "1.0.0")] +pub struct ExitStatus(imp::ExitStatus); + +impl ExitStatus { + /// Was termination successful? Signal termination is not considered a + /// success, and success is defined as a zero exit status. + /// + /// # Examples + /// + /// ```rust,no_run + /// use std::process::Command; + /// + /// let status = Command::new("mkdir") + /// .arg("projects") + /// .status() + /// .expect("failed to execute mkdir"); + /// + /// if status.success() { + /// println!("'projects/' directory created"); + /// } else { + /// println!("failed to create 'projects/' directory"); + /// } + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn success(&self) -> bool { + self.0.success() + } + + /// Returns the exit code of the process, if any. + /// + /// On Unix, this will return `None` if the process was terminated + /// by a signal; `std::os::unix` provides an extension trait for + /// extracting the signal and other details from the `ExitStatus`. + /// + /// # Examples + /// + /// ```no_run + /// use std::process::Command; + /// + /// let status = Command::new("mkdir") + /// .arg("projects") + /// .status() + /// .expect("failed to execute mkdir"); + /// + /// match status.code() { + /// Some(code) => println!("Exited with status code: {}", code), + /// None => println!("Process terminated by signal") + /// } + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn code(&self) -> Option<i32> { + self.0.code() + } +} + +impl AsInner<imp::ExitStatus> for ExitStatus { + fn as_inner(&self) -> &imp::ExitStatus { + &self.0 + } +} + +impl FromInner<imp::ExitStatus> for ExitStatus { + fn from_inner(s: imp::ExitStatus) -> ExitStatus { + ExitStatus(s) + } +} + +#[stable(feature = "process", since = "1.0.0")] +impl fmt::Display for ExitStatus { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.0.fmt(f) + } +} + +/// This type represents the status code a process can return to its +/// parent under normal termination. +/// +/// Numeric values used in this type don't have portable meanings, and +/// different platforms may mask different amounts of them. +/// +/// For the platform's canonical successful and unsuccessful codes, see +/// the [`SUCCESS`] and [`FAILURE`] associated items. +/// +/// [`SUCCESS`]: #associatedconstant.SUCCESS +/// [`FAILURE`]: #associatedconstant.FAILURE +/// +/// **Warning**: While various forms of this were discussed in [RFC #1937], +/// it was ultimately cut from that RFC, and thus this type is more subject +/// to change even than the usual unstable item churn. +/// +/// [RFC #1937]: https://github.com/rust-lang/rfcs/pull/1937 +#[derive(Clone, Copy, Debug)] +#[unstable(feature = "process_exitcode_placeholder", issue = "48711")] +pub struct ExitCode(imp::ExitCode); + +#[unstable(feature = "process_exitcode_placeholder", issue = "48711")] +impl ExitCode { + /// The canonical ExitCode for successful termination on this platform. + /// + /// Note that a `()`-returning `main` implicitly results in a successful + /// termination, so there's no need to return this from `main` unless + /// you're also returning other possible codes. + #[unstable(feature = "process_exitcode_placeholder", issue = "48711")] + pub const SUCCESS: ExitCode = ExitCode(imp::ExitCode::SUCCESS); + + /// The canonical ExitCode for unsuccessful termination on this platform. + /// + /// If you're only returning this and `SUCCESS` from `main`, consider + /// instead returning `Err(_)` and `Ok(())` respectively, which will + /// return the same codes (but will also `eprintln!` the error). + #[unstable(feature = "process_exitcode_placeholder", issue = "48711")] + pub const FAILURE: ExitCode = ExitCode(imp::ExitCode::FAILURE); +} + +impl Child { + /// Forces the child process to exit. If the child has already exited, an [`InvalidInput`] + /// error is returned. + /// + /// The mapping to [`ErrorKind`]s is not part of the compatibility contract of the function, + /// especially the [`Other`] kind might change to more specific kinds in the future. + /// + /// This is equivalent to sending a SIGKILL on Unix platforms. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// let mut command = Command::new("yes"); + /// if let Ok(mut child) = command.spawn() { + /// child.kill().expect("command wasn't running"); + /// } else { + /// println!("yes command didn't start"); + /// } + /// ``` + /// + /// [`ErrorKind`]: ../io/enum.ErrorKind.html + /// [`InvalidInput`]: ../io/enum.ErrorKind.html#variant.InvalidInput + /// [`Other`]: ../io/enum.ErrorKind.html#variant.Other + #[stable(feature = "process", since = "1.0.0")] + pub fn kill(&mut self) -> io::Result<()> { + self.handle.kill() + } + + /// Returns the OS-assigned process identifier associated with this child. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// let mut command = Command::new("ls"); + /// if let Ok(child) = command.spawn() { + /// println!("Child's ID is {}", child.id()); + /// } else { + /// println!("ls command didn't start"); + /// } + /// ``` + #[stable(feature = "process_id", since = "1.3.0")] + pub fn id(&self) -> u32 { + self.handle.id() + } + + /// Waits for the child to exit completely, returning the status that it + /// exited with. This function will continue to have the same return value + /// after it has been called at least once. + /// + /// The stdin handle to the child process, if any, will be closed + /// before waiting. This helps avoid deadlock: it ensures that the + /// child does not block waiting for input from the parent, while + /// the parent waits for the child to exit. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// let mut command = Command::new("ls"); + /// if let Ok(mut child) = command.spawn() { + /// child.wait().expect("command wasn't running"); + /// println!("Child has finished its execution!"); + /// } else { + /// println!("ls command didn't start"); + /// } + /// ``` + #[stable(feature = "process", since = "1.0.0")] + pub fn wait(&mut self) -> io::Result<ExitStatus> { + drop(self.stdin.take()); + self.handle.wait().map(ExitStatus) + } + + /// Attempts to collect the exit status of the child if it has already + /// exited. + /// + /// This function will not block the calling thread and will only + /// check to see if the child process has exited or not. If the child has + /// exited then on Unix the process ID is reaped. This function is + /// guaranteed to repeatedly return a successful exit status so long as the + /// child has already exited. + /// + /// If the child has exited, then `Ok(Some(status))` is returned. If the + /// exit status is not available at this time then `Ok(None)` is returned. + /// If an error occurs, then that error is returned. + /// + /// Note that unlike `wait`, this function will not attempt to drop stdin. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ```no_run + /// use std::process::Command; + /// + /// let mut child = Command::new("ls").spawn().unwrap(); + /// + /// match child.try_wait() { + /// Ok(Some(status)) => println!("exited with: {}", status), + /// Ok(None) => { + /// println!("status not ready yet, let's really wait"); + /// let res = child.wait(); + /// println!("result: {:?}", res); + /// } + /// Err(e) => println!("error attempting to wait: {}", e), + /// } + /// ``` + #[stable(feature = "process_try_wait", since = "1.18.0")] + pub fn try_wait(&mut self) -> io::Result<Option<ExitStatus>> { + Ok(self.handle.try_wait()?.map(ExitStatus)) + } + + /// Simultaneously waits for the child to exit and collect all remaining + /// output on the stdout/stderr handles, returning an `Output` + /// instance. + /// + /// The stdin handle to the child process, if any, will be closed + /// before waiting. This helps avoid deadlock: it ensures that the + /// child does not block waiting for input from the parent, while + /// the parent waits for the child to exit. + /// + /// By default, stdin, stdout and stderr are inherited from the parent. + /// In order to capture the output into this `Result<Output>` it is + /// necessary to create new pipes between parent and child. Use + /// `stdout(Stdio::piped())` or `stderr(Stdio::piped())`, respectively. + /// + /// # Examples + /// + /// ```should_panic + /// use std::process::{Command, Stdio}; + /// + /// let child = Command::new("/bin/cat") + /// .arg("file.txt") + /// .stdout(Stdio::piped()) + /// .spawn() + /// .expect("failed to execute child"); + /// + /// let output = child + /// .wait_with_output() + /// .expect("failed to wait on child"); + /// + /// assert!(output.status.success()); + /// ``` + /// + #[stable(feature = "process", since = "1.0.0")] + pub fn wait_with_output(mut self) -> io::Result<Output> { + drop(self.stdin.take()); + + let (mut stdout, mut stderr) = (Vec::new(), Vec::new()); + match (self.stdout.take(), self.stderr.take()) { + (None, None) => {} + (Some(mut out), None) => { + let res = out.read_to_end(&mut stdout); + res.unwrap(); + } + (None, Some(mut err)) => { + let res = err.read_to_end(&mut stderr); + res.unwrap(); + } + (Some(out), Some(err)) => { + let res = read2(out.inner, &mut stdout, err.inner, &mut stderr); + res.unwrap(); + } + } + + let status = self.wait()?; + Ok(Output { status, stdout, stderr }) + } +} + +/// Terminates the current process with the specified exit code. +/// +/// This function will never return and will immediately terminate the current +/// process. The exit code is passed through to the underlying OS and will be +/// available for consumption by another process. +/// +/// Note that because this function never returns, and that it terminates the +/// process, no destructors on the current stack or any other thread's stack +/// will be run. If a clean shutdown is needed it is recommended to only call +/// this function at a known point where there are no more destructors left +/// to run. +/// +/// ## Platform-specific behavior +/// +/// **Unix**: On Unix-like platforms, it is unlikely that all 32 bits of `exit` +/// will be visible to a parent process inspecting the exit code. On most +/// Unix-like platforms, only the eight least-significant bits are considered. +/// +/// # Examples +/// +/// Due to this function’s behavior regarding destructors, a conventional way +/// to use the function is to extract the actual computation to another +/// function and compute the exit code from its return value: +/// +/// ``` +/// fn run_app() -> Result<(), ()> { +/// // Application logic here +/// Ok(()) +/// } +/// +/// fn main() { +/// std::process::exit(match run_app() { +/// Ok(_) => 0, +/// Err(err) => { +/// eprintln!("error: {:?}", err); +/// 1 +/// } +/// }); +/// } +/// ``` +/// +/// Due to [platform-specific behavior], the exit code for this example will be +/// `0` on Linux, but `256` on Windows: +/// +/// ```no_run +/// use std::process; +/// +/// process::exit(0x0100); +/// ``` +/// +/// [platform-specific behavior]: #platform-specific-behavior +#[stable(feature = "rust1", since = "1.0.0")] +pub fn exit(code: i32) -> ! { + crate::sys_common::cleanup(); + crate::sys::os::exit(code) +} + +/// Terminates the process in an abnormal fashion. +/// +/// The function will never return and will immediately terminate the current +/// process in a platform specific "abnormal" manner. +/// +/// Note that because this function never returns, and that it terminates the +/// process, no destructors on the current stack or any other thread's stack +/// will be run. +/// +/// This is in contrast to the default behaviour of [`panic!`] which unwinds +/// the current thread's stack and calls all destructors. +/// When `panic="abort"` is set, either as an argument to `rustc` or in a +/// crate's Cargo.toml, [`panic!`] and `abort` are similar. However, +/// [`panic!`] will still call the [panic hook] while `abort` will not. +/// +/// If a clean shutdown is needed it is recommended to only call +/// this function at a known point where there are no more destructors left +/// to run. +/// +/// # Examples +/// +/// ```no_run +/// use std::process; +/// +/// fn main() { +/// println!("aborting"); +/// +/// process::abort(); +/// +/// // execution never gets here +/// } +/// ``` +/// +/// The `abort` function terminates the process, so the destructor will not +/// get run on the example below: +/// +/// ```no_run +/// use std::process; +/// +/// struct HasDrop; +/// +/// impl Drop for HasDrop { +/// fn drop(&mut self) { +/// println!("This will never be printed!"); +/// } +/// } +/// +/// fn main() { +/// let _x = HasDrop; +/// process::abort(); +/// // the destructor implemented for HasDrop will never get run +/// } +/// ``` +/// +/// [`panic!`]: ../../std/macro.panic.html +/// [panic hook]: ../../std/panic/fn.set_hook.html +#[stable(feature = "process_abort", since = "1.17.0")] +pub fn abort() -> ! { + crate::sys::abort_internal(); +} + +/// Returns the OS-assigned process identifier associated with this process. +/// +/// # Examples +/// +/// Basic usage: +/// +/// ```no_run +/// use std::process; +/// +/// println!("My pid is {}", process::id()); +/// ``` +/// +/// +#[stable(feature = "getpid", since = "1.26.0")] +pub fn id() -> u32 { + crate::sys::os::getpid() +} + +/// A trait for implementing arbitrary return types in the `main` function. +/// +/// The C-main function only supports to return integers as return type. +/// So, every type implementing the `Termination` trait has to be converted +/// to an integer. +/// +/// The default implementations are returning `libc::EXIT_SUCCESS` to indicate +/// a successful execution. In case of a failure, `libc::EXIT_FAILURE` is returned. +#[cfg_attr(not(test), lang = "termination")] +#[unstable(feature = "termination_trait_lib", issue = "43301")] +#[rustc_on_unimplemented( + message = "`main` has invalid return type `{Self}`", + label = "`main` can only return types that implement `{Termination}`" +)] +pub trait Termination { + /// Is called to get the representation of the value as status code. + /// This status code is returned to the operating system. + fn report(self) -> i32; +} + +#[unstable(feature = "termination_trait_lib", issue = "43301")] +impl Termination for () { + #[inline] + fn report(self) -> i32 { + ExitCode::SUCCESS.report() + } +} + +#[unstable(feature = "termination_trait_lib", issue = "43301")] +impl<E: fmt::Debug> Termination for Result<(), E> { + fn report(self) -> i32 { + match self { + Ok(()) => ().report(), + Err(err) => Err::<!, _>(err).report(), + } + } +} + +#[unstable(feature = "termination_trait_lib", issue = "43301")] +impl Termination for ! { + fn report(self) -> i32 { + self + } +} + +#[unstable(feature = "termination_trait_lib", issue = "43301")] +impl<E: fmt::Debug> Termination for Result<!, E> { + fn report(self) -> i32 { + let Err(err) = self; + eprintln!("Error: {:?}", err); + ExitCode::FAILURE.report() + } +} + +#[unstable(feature = "termination_trait_lib", issue = "43301")] +impl Termination for ExitCode { + #[inline] + fn report(self) -> i32 { + self.0.as_i32() + } +} + +#[cfg(all(test, not(any(target_os = "cloudabi", target_os = "emscripten", target_env = "sgx"))))] +mod tests { + use crate::io::prelude::*; + + use super::{Command, Output, Stdio}; + use crate::io::ErrorKind; + use crate::str; + + // FIXME(#10380) these tests should not all be ignored on android. + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn smoke() { + let p = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "exit 0"]).spawn() + } else { + Command::new("true").spawn() + }; + assert!(p.is_ok()); + let mut p = p.unwrap(); + assert!(p.wait().unwrap().success()); + } + + #[test] + #[cfg_attr(target_os = "android", ignore)] + fn smoke_failure() { + match Command::new("if-this-is-a-binary-then-the-world-has-ended").spawn() { + Ok(..) => panic!(), + Err(..) => {} + } + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn exit_reported_right() { + let p = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "exit 1"]).spawn() + } else { + Command::new("false").spawn() + }; + assert!(p.is_ok()); + let mut p = p.unwrap(); + assert!(p.wait().unwrap().code() == Some(1)); + drop(p.wait()); + } + + #[test] + #[cfg(unix)] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn signal_reported_right() { + use crate::os::unix::process::ExitStatusExt; + + let mut p = + Command::new("/bin/sh").arg("-c").arg("read a").stdin(Stdio::piped()).spawn().unwrap(); + p.kill().unwrap(); + match p.wait().unwrap().signal() { + Some(9) => {} + result => panic!("not terminated by signal 9 (instead, {:?})", result), + } + } + + pub fn run_output(mut cmd: Command) -> String { + let p = cmd.spawn(); + assert!(p.is_ok()); + let mut p = p.unwrap(); + assert!(p.stdout.is_some()); + let mut ret = String::new(); + p.stdout.as_mut().unwrap().read_to_string(&mut ret).unwrap(); + assert!(p.wait().unwrap().success()); + return ret; + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn stdout_works() { + if cfg!(target_os = "windows") { + let mut cmd = Command::new("cmd"); + cmd.args(&["/C", "echo foobar"]).stdout(Stdio::piped()); + assert_eq!(run_output(cmd), "foobar\r\n"); + } else { + let mut cmd = Command::new("echo"); + cmd.arg("foobar").stdout(Stdio::piped()); + assert_eq!(run_output(cmd), "foobar\n"); + } + } + + #[test] + #[cfg_attr(any(windows, target_os = "android", target_os = "vxworks"), ignore)] + fn set_current_dir_works() { + let mut cmd = Command::new("/bin/sh"); + cmd.arg("-c").arg("pwd").current_dir("/").stdout(Stdio::piped()); + assert_eq!(run_output(cmd), "/\n"); + } + + #[test] + #[cfg_attr(any(windows, target_os = "android", target_os = "vxworks"), ignore)] + fn stdin_works() { + let mut p = Command::new("/bin/sh") + .arg("-c") + .arg("read line; echo $line") + .stdin(Stdio::piped()) + .stdout(Stdio::piped()) + .spawn() + .unwrap(); + p.stdin.as_mut().unwrap().write("foobar".as_bytes()).unwrap(); + drop(p.stdin.take()); + let mut out = String::new(); + p.stdout.as_mut().unwrap().read_to_string(&mut out).unwrap(); + assert!(p.wait().unwrap().success()); + assert_eq!(out, "foobar\n"); + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn test_process_status() { + let mut status = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "exit 1"]).status().unwrap() + } else { + Command::new("false").status().unwrap() + }; + assert!(status.code() == Some(1)); + + status = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "exit 0"]).status().unwrap() + } else { + Command::new("true").status().unwrap() + }; + assert!(status.success()); + } + + #[test] + fn test_process_output_fail_to_start() { + match Command::new("/no-binary-by-this-name-should-exist").output() { + Err(e) => assert_eq!(e.kind(), ErrorKind::NotFound), + Ok(..) => panic!(), + } + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn test_process_output_output() { + let Output { status, stdout, stderr } = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "echo hello"]).output().unwrap() + } else { + Command::new("echo").arg("hello").output().unwrap() + }; + let output_str = str::from_utf8(&stdout).unwrap(); + + assert!(status.success()); + assert_eq!(output_str.trim().to_string(), "hello"); + assert_eq!(stderr, Vec::new()); + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn test_process_output_error() { + let Output { status, stdout, stderr } = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "mkdir ."]).output().unwrap() + } else { + Command::new("mkdir").arg("./").output().unwrap() + }; + + assert!(status.code() == Some(1)); + assert_eq!(stdout, Vec::new()); + assert!(!stderr.is_empty()); + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn test_finish_once() { + let mut prog = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "exit 1"]).spawn().unwrap() + } else { + Command::new("false").spawn().unwrap() + }; + assert!(prog.wait().unwrap().code() == Some(1)); + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn test_finish_twice() { + let mut prog = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "exit 1"]).spawn().unwrap() + } else { + Command::new("false").spawn().unwrap() + }; + assert!(prog.wait().unwrap().code() == Some(1)); + assert!(prog.wait().unwrap().code() == Some(1)); + } + + #[test] + #[cfg_attr(any(target_os = "vxworks", target_os = "android"), ignore)] + fn test_wait_with_output_once() { + let prog = if cfg!(target_os = "windows") { + Command::new("cmd").args(&["/C", "echo hello"]).stdout(Stdio::piped()).spawn().unwrap() + } else { + Command::new("echo").arg("hello").stdout(Stdio::piped()).spawn().unwrap() + }; + + let Output { status, stdout, stderr } = prog.wait_with_output().unwrap(); + let output_str = str::from_utf8(&stdout).unwrap(); + + assert!(status.success()); + assert_eq!(output_str.trim().to_string(), "hello"); + assert_eq!(stderr, Vec::new()); + } + + #[cfg(all(unix, not(target_os = "android")))] + pub fn env_cmd() -> Command { + Command::new("env") + } + #[cfg(target_os = "android")] + pub fn env_cmd() -> Command { + let mut cmd = Command::new("/system/bin/sh"); + cmd.arg("-c").arg("set"); + cmd + } + + #[cfg(windows)] + pub fn env_cmd() -> Command { + let mut cmd = Command::new("cmd"); + cmd.arg("/c").arg("set"); + cmd + } + + #[test] + #[cfg_attr(target_os = "vxworks", ignore)] + fn test_override_env() { + use crate::env; + + // In some build environments (such as chrooted Nix builds), `env` can + // only be found in the explicitly-provided PATH env variable, not in + // default places such as /bin or /usr/bin. So we need to pass through + // PATH to our sub-process. + let mut cmd = env_cmd(); + cmd.env_clear().env("RUN_TEST_NEW_ENV", "123"); + if let Some(p) = env::var_os("PATH") { + cmd.env("PATH", &p); + } + let result = cmd.output().unwrap(); + let output = String::from_utf8_lossy(&result.stdout).to_string(); + + assert!( + output.contains("RUN_TEST_NEW_ENV=123"), + "didn't find RUN_TEST_NEW_ENV inside of:\n\n{}", + output + ); + } + + #[test] + #[cfg_attr(target_os = "vxworks", ignore)] + fn test_add_to_env() { + let result = env_cmd().env("RUN_TEST_NEW_ENV", "123").output().unwrap(); + let output = String::from_utf8_lossy(&result.stdout).to_string(); + + assert!( + output.contains("RUN_TEST_NEW_ENV=123"), + "didn't find RUN_TEST_NEW_ENV inside of:\n\n{}", + output + ); + } + + #[test] + #[cfg_attr(target_os = "vxworks", ignore)] + fn test_capture_env_at_spawn() { + use crate::env; + + let mut cmd = env_cmd(); + cmd.env("RUN_TEST_NEW_ENV1", "123"); + + // This variable will not be present if the environment has already + // been captured above. + env::set_var("RUN_TEST_NEW_ENV2", "456"); + let result = cmd.output().unwrap(); + env::remove_var("RUN_TEST_NEW_ENV2"); + + let output = String::from_utf8_lossy(&result.stdout).to_string(); + + assert!( + output.contains("RUN_TEST_NEW_ENV1=123"), + "didn't find RUN_TEST_NEW_ENV1 inside of:\n\n{}", + output + ); + assert!( + output.contains("RUN_TEST_NEW_ENV2=456"), + "didn't find RUN_TEST_NEW_ENV2 inside of:\n\n{}", + output + ); + } + + // Regression tests for #30858. + #[test] + fn test_interior_nul_in_progname_is_error() { + match Command::new("has-some-\0\0s-inside").spawn() { + Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput), + Ok(_) => panic!(), + } + } + + #[test] + fn test_interior_nul_in_arg_is_error() { + match Command::new("echo").arg("has-some-\0\0s-inside").spawn() { + Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput), + Ok(_) => panic!(), + } + } + + #[test] + fn test_interior_nul_in_args_is_error() { + match Command::new("echo").args(&["has-some-\0\0s-inside"]).spawn() { + Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput), + Ok(_) => panic!(), + } + } + + #[test] + fn test_interior_nul_in_current_dir_is_error() { + match Command::new("echo").current_dir("has-some-\0\0s-inside").spawn() { + Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput), + Ok(_) => panic!(), + } + } + + // Regression tests for #30862. + #[test] + #[cfg_attr(target_os = "vxworks", ignore)] + fn test_interior_nul_in_env_key_is_error() { + match env_cmd().env("has-some-\0\0s-inside", "value").spawn() { + Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput), + Ok(_) => panic!(), + } + } + + #[test] + #[cfg_attr(target_os = "vxworks", ignore)] + fn test_interior_nul_in_env_value_is_error() { + match env_cmd().env("key", "has-some-\0\0s-inside").spawn() { + Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput), + Ok(_) => panic!(), + } + } + + /// Tests that process creation flags work by debugging a process. + /// Other creation flags make it hard or impossible to detect + /// behavioral changes in the process. + #[test] + #[cfg(windows)] + fn test_creation_flags() { + use crate::os::windows::process::CommandExt; + use crate::sys::c::{BOOL, DWORD, INFINITE}; + #[repr(C, packed)] + struct DEBUG_EVENT { + pub event_code: DWORD, + pub process_id: DWORD, + pub thread_id: DWORD, + // This is a union in the real struct, but we don't + // need this data for the purposes of this test. + pub _junk: [u8; 164], + } + + extern "system" { + fn WaitForDebugEvent(lpDebugEvent: *mut DEBUG_EVENT, dwMilliseconds: DWORD) -> BOOL; + fn ContinueDebugEvent( + dwProcessId: DWORD, + dwThreadId: DWORD, + dwContinueStatus: DWORD, + ) -> BOOL; + } + + const DEBUG_PROCESS: DWORD = 1; + const EXIT_PROCESS_DEBUG_EVENT: DWORD = 5; + const DBG_EXCEPTION_NOT_HANDLED: DWORD = 0x80010001; + + let mut child = Command::new("cmd") + .creation_flags(DEBUG_PROCESS) + .stdin(Stdio::piped()) + .spawn() + .unwrap(); + child.stdin.take().unwrap().write_all(b"exit\r\n").unwrap(); + let mut events = 0; + let mut event = DEBUG_EVENT { event_code: 0, process_id: 0, thread_id: 0, _junk: [0; 164] }; + loop { + if unsafe { WaitForDebugEvent(&mut event as *mut DEBUG_EVENT, INFINITE) } == 0 { + panic!("WaitForDebugEvent failed!"); + } + events += 1; + + if event.event_code == EXIT_PROCESS_DEBUG_EVENT { + break; + } + + if unsafe { + ContinueDebugEvent(event.process_id, event.thread_id, DBG_EXCEPTION_NOT_HANDLED) + } == 0 + { + panic!("ContinueDebugEvent failed!"); + } + } + assert!(events > 0); + } + + #[test] + fn test_command_implements_send_sync() { + fn take_send_sync_type<T: Send + Sync>(_: T) {} + take_send_sync_type(Command::new("")) + } +} |