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| author | Vivian Lim <[email protected]> | 2021-02-06 22:11:59 -0800 |
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| committer | Vivian Lim <[email protected]> | 2021-02-06 22:11:59 -0800 |
| commit | 64423f0e34cc4a7d78c15b345b3b8f58243d8286 (patch) | |
| tree | cc20e2e7f0fc35abf470e20e61d3d48f0d954f3b /ctr-std/src/sys/redox/process.rs | |
| parent | Support libctru 2.0 (diff) | |
| download | ctru-rs-64423f0e34cc4a7d78c15b345b3b8f58243d8286.tar.xz ctru-rs-64423f0e34cc4a7d78c15b345b3b8f58243d8286.zip | |
Delete ctr-std to use my fork of the rust repo instead
Diffstat (limited to 'ctr-std/src/sys/redox/process.rs')
| -rw-r--r-- | ctr-std/src/sys/redox/process.rs | 544 |
1 files changed, 0 insertions, 544 deletions
diff --git a/ctr-std/src/sys/redox/process.rs b/ctr-std/src/sys/redox/process.rs deleted file mode 100644 index 2037616..0000000 --- a/ctr-std/src/sys/redox/process.rs +++ /dev/null @@ -1,544 +0,0 @@ -// Copyright 2016 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -use env::{split_paths}; -use ffi::OsStr; -use os::unix::ffi::OsStrExt; -use fmt; -use io::{self, Error, ErrorKind}; -use iter; -use libc::{EXIT_SUCCESS, EXIT_FAILURE}; -use path::{Path, PathBuf}; -use sys::fd::FileDesc; -use sys::fs::{File, OpenOptions}; -use sys::pipe::{self, AnonPipe}; -use sys::{cvt, syscall}; -use sys_common::process::{CommandEnv, DefaultEnvKey}; - -//////////////////////////////////////////////////////////////////////////////// -// Command -//////////////////////////////////////////////////////////////////////////////// - -pub struct Command { - // Currently we try hard to ensure that the call to `.exec()` doesn't - // actually allocate any memory. While many platforms try to ensure that - // memory allocation works after a fork in a multithreaded process, it's - // been observed to be buggy and somewhat unreliable, so we do our best to - // just not do it at all! - // - // Along those lines, the `argv` and `envp` raw pointers here are exactly - // what's gonna get passed to `execvp`. The `argv` array starts with the - // `program` and ends with a NULL, and the `envp` pointer, if present, is - // also null-terminated. - // - // Right now we don't support removing arguments, so there's no much fancy - // support there, but we support adding and removing environment variables, - // so a side table is used to track where in the `envp` array each key is - // located. Whenever we add a key we update it in place if it's already - // present, and whenever we remove a key we update the locations of all - // other keys. - program: String, - args: Vec<String>, - env: CommandEnv<DefaultEnvKey>, - - cwd: Option<String>, - uid: Option<u32>, - gid: Option<u32>, - saw_nul: bool, - closures: Vec<Box<dyn FnMut() -> io::Result<()> + Send + Sync>>, - stdin: Option<Stdio>, - stdout: Option<Stdio>, - stderr: Option<Stdio>, -} - -// passed back to std::process with the pipes connected to the child, if any -// were requested -pub struct StdioPipes { - pub stdin: Option<AnonPipe>, - pub stdout: Option<AnonPipe>, - pub stderr: Option<AnonPipe>, -} - -// passed to do_exec() with configuration of what the child stdio should look -// like -struct ChildPipes { - stdin: ChildStdio, - stdout: ChildStdio, - stderr: ChildStdio, -} - -enum ChildStdio { - Inherit, - Explicit(usize), - Owned(FileDesc), -} - -pub enum Stdio { - Inherit, - Null, - MakePipe, - Fd(FileDesc), -} - -impl Command { - pub fn new(program: &OsStr) -> Command { - Command { - program: program.to_str().unwrap().to_owned(), - args: Vec::new(), - env: Default::default(), - cwd: None, - uid: None, - gid: None, - saw_nul: false, - closures: Vec::new(), - stdin: None, - stdout: None, - stderr: None, - } - } - - pub fn arg(&mut self, arg: &OsStr) { - self.args.push(arg.to_str().unwrap().to_owned()); - } - - pub fn env_mut(&mut self) -> &mut CommandEnv<DefaultEnvKey> { - &mut self.env - } - - pub fn cwd(&mut self, dir: &OsStr) { - self.cwd = Some(dir.to_str().unwrap().to_owned()); - } - pub fn uid(&mut self, id: u32) { - self.uid = Some(id); - } - pub fn gid(&mut self, id: u32) { - self.gid = Some(id); - } - - pub fn before_exec(&mut self, - f: Box<dyn FnMut() -> io::Result<()> + Send + Sync>) { - self.closures.push(f); - } - - pub fn stdin(&mut self, stdin: Stdio) { - self.stdin = Some(stdin); - } - pub fn stdout(&mut self, stdout: Stdio) { - self.stdout = Some(stdout); - } - pub fn stderr(&mut self, stderr: Stdio) { - self.stderr = Some(stderr); - } - - pub fn spawn(&mut self, default: Stdio, needs_stdin: bool) - -> io::Result<(Process, StdioPipes)> { - const CLOEXEC_MSG_FOOTER: &'static [u8] = b"NOEX"; - - if self.saw_nul { - return Err(io::Error::new(ErrorKind::InvalidInput, - "nul byte found in provided data")); - } - - let (ours, theirs) = self.setup_io(default, needs_stdin)?; - let (input, output) = pipe::anon_pipe()?; - - let pid = unsafe { - match cvt(syscall::clone(0))? { - 0 => { - drop(input); - let err = self.do_exec(theirs); - let errno = err.raw_os_error().unwrap_or(syscall::EINVAL) as u32; - let bytes = [ - (errno >> 24) as u8, - (errno >> 16) as u8, - (errno >> 8) as u8, - (errno >> 0) as u8, - CLOEXEC_MSG_FOOTER[0], CLOEXEC_MSG_FOOTER[1], - CLOEXEC_MSG_FOOTER[2], CLOEXEC_MSG_FOOTER[3] - ]; - // pipe I/O up to PIPE_BUF bytes should be atomic, and then - // we want to be sure we *don't* run at_exit destructors as - // we're being torn down regardless - assert!(output.write(&bytes).is_ok()); - let _ = syscall::exit(1); - panic!("failed to exit"); - } - n => n, - } - }; - - let mut p = Process { pid: pid, status: None }; - drop(output); - let mut bytes = [0; 8]; - - // loop to handle EINTR - loop { - match input.read(&mut bytes) { - Ok(0) => return Ok((p, ours)), - Ok(8) => { - assert!(combine(CLOEXEC_MSG_FOOTER) == combine(&bytes[4.. 8]), - "Validation on the CLOEXEC pipe failed: {:?}", bytes); - let errno = combine(&bytes[0.. 4]); - assert!(p.wait().is_ok(), - "wait() should either return Ok or panic"); - return Err(Error::from_raw_os_error(errno)) - } - Err(ref e) if e.kind() == ErrorKind::Interrupted => {} - Err(e) => { - assert!(p.wait().is_ok(), - "wait() should either return Ok or panic"); - panic!("the CLOEXEC pipe failed: {:?}", e) - }, - Ok(..) => { // pipe I/O up to PIPE_BUF bytes should be atomic - assert!(p.wait().is_ok(), - "wait() should either return Ok or panic"); - panic!("short read on the CLOEXEC pipe") - } - } - } - - fn combine(arr: &[u8]) -> i32 { - let a = arr[0] as u32; - let b = arr[1] as u32; - let c = arr[2] as u32; - let d = arr[3] as u32; - - ((a << 24) | (b << 16) | (c << 8) | (d << 0)) as i32 - } - } - - pub fn exec(&mut self, default: Stdio) -> io::Error { - if self.saw_nul { - return io::Error::new(ErrorKind::InvalidInput, - "nul byte found in provided data") - } - - match self.setup_io(default, true) { - Ok((_, theirs)) => unsafe { self.do_exec(theirs) }, - Err(e) => e, - } - } - - // And at this point we've reached a special time in the life of the - // child. The child must now be considered hamstrung and unable to - // do anything other than syscalls really. Consider the following - // scenario: - // - // 1. Thread A of process 1 grabs the malloc() mutex - // 2. Thread B of process 1 forks(), creating thread C - // 3. Thread C of process 2 then attempts to malloc() - // 4. The memory of process 2 is the same as the memory of - // process 1, so the mutex is locked. - // - // This situation looks a lot like deadlock, right? It turns out - // that this is what pthread_atfork() takes care of, which is - // presumably implemented across platforms. The first thing that - // threads to *before* forking is to do things like grab the malloc - // mutex, and then after the fork they unlock it. - // - // Despite this information, libnative's spawn has been witnessed to - // deadlock on both macOS and FreeBSD. I'm not entirely sure why, but - // all collected backtraces point at malloc/free traffic in the - // child spawned process. - // - // For this reason, the block of code below should contain 0 - // invocations of either malloc of free (or their related friends). - // - // As an example of not having malloc/free traffic, we don't close - // this file descriptor by dropping the FileDesc (which contains an - // allocation). Instead we just close it manually. This will never - // have the drop glue anyway because this code never returns (the - // child will either exec() or invoke syscall::exit) - unsafe fn do_exec(&mut self, stdio: ChildPipes) -> io::Error { - macro_rules! t { - ($e:expr) => (match $e { - Ok(e) => e, - Err(e) => return e, - }) - } - - if let Some(fd) = stdio.stderr.fd() { - t!(cvt(syscall::dup2(fd, 2, &[]))); - let mut flags = t!(cvt(syscall::fcntl(2, syscall::F_GETFD, 0))); - flags &= ! syscall::O_CLOEXEC; - t!(cvt(syscall::fcntl(2, syscall::F_SETFD, flags))); - } - if let Some(fd) = stdio.stdout.fd() { - t!(cvt(syscall::dup2(fd, 1, &[]))); - let mut flags = t!(cvt(syscall::fcntl(1, syscall::F_GETFD, 0))); - flags &= ! syscall::O_CLOEXEC; - t!(cvt(syscall::fcntl(1, syscall::F_SETFD, flags))); - } - if let Some(fd) = stdio.stdin.fd() { - t!(cvt(syscall::dup2(fd, 0, &[]))); - let mut flags = t!(cvt(syscall::fcntl(0, syscall::F_GETFD, 0))); - flags &= ! syscall::O_CLOEXEC; - t!(cvt(syscall::fcntl(0, syscall::F_SETFD, flags))); - } - - if let Some(g) = self.gid { - t!(cvt(syscall::setregid(g as usize, g as usize))); - } - if let Some(u) = self.uid { - t!(cvt(syscall::setreuid(u as usize, u as usize))); - } - if let Some(ref cwd) = self.cwd { - t!(cvt(syscall::chdir(cwd))); - } - - for callback in self.closures.iter_mut() { - t!(callback()); - } - - let args: Vec<[usize; 2]> = iter::once( - [self.program.as_ptr() as usize, self.program.len()] - ).chain( - self.args.iter().map(|arg| [arg.as_ptr() as usize, arg.len()]) - ).collect(); - - self.env.apply(); - - let program = if self.program.contains(':') || self.program.contains('/') { - Some(PathBuf::from(&self.program)) - } else if let Ok(path_env) = ::env::var("PATH") { - let mut program = None; - for mut path in split_paths(&path_env) { - path.push(&self.program); - if path.exists() { - program = Some(path); - break; - } - } - program - } else { - None - }; - - if let Some(program) = program { - if let Err(err) = syscall::execve(program.as_os_str().as_bytes(), &args) { - io::Error::from_raw_os_error(err.errno as i32) - } else { - panic!("return from exec without err"); - } - } else { - io::Error::from_raw_os_error(syscall::ENOENT) - } - } - - - fn setup_io(&self, default: Stdio, needs_stdin: bool) - -> io::Result<(StdioPipes, ChildPipes)> { - let null = Stdio::Null; - let default_stdin = if needs_stdin {&default} else {&null}; - let stdin = self.stdin.as_ref().unwrap_or(default_stdin); - let stdout = self.stdout.as_ref().unwrap_or(&default); - let stderr = self.stderr.as_ref().unwrap_or(&default); - let (their_stdin, our_stdin) = stdin.to_child_stdio(true)?; - let (their_stdout, our_stdout) = stdout.to_child_stdio(false)?; - let (their_stderr, our_stderr) = stderr.to_child_stdio(false)?; - let ours = StdioPipes { - stdin: our_stdin, - stdout: our_stdout, - stderr: our_stderr, - }; - let theirs = ChildPipes { - stdin: their_stdin, - stdout: their_stdout, - stderr: their_stderr, - }; - Ok((ours, theirs)) - } -} - -impl Stdio { - fn to_child_stdio(&self, readable: bool) - -> io::Result<(ChildStdio, Option<AnonPipe>)> { - match *self { - Stdio::Inherit => Ok((ChildStdio::Inherit, None)), - - // Make sure that the source descriptors are not an stdio - // descriptor, otherwise the order which we set the child's - // descriptors may blow away a descriptor which we are hoping to - // save. For example, suppose we want the child's stderr to be the - // parent's stdout, and the child's stdout to be the parent's - // stderr. No matter which we dup first, the second will get - // overwritten prematurely. - Stdio::Fd(ref fd) => { - if fd.raw() <= 2 { - Ok((ChildStdio::Owned(fd.duplicate()?), None)) - } else { - Ok((ChildStdio::Explicit(fd.raw()), None)) - } - } - - Stdio::MakePipe => { - let (reader, writer) = pipe::anon_pipe()?; - let (ours, theirs) = if readable { - (writer, reader) - } else { - (reader, writer) - }; - Ok((ChildStdio::Owned(theirs.into_fd()), Some(ours))) - } - - Stdio::Null => { - let mut opts = OpenOptions::new(); - opts.read(readable); - opts.write(!readable); - let fd = File::open(Path::new("null:"), &opts)?; - Ok((ChildStdio::Owned(fd.into_fd()), None)) - } - } - } -} - -impl From<AnonPipe> for Stdio { - fn from(pipe: AnonPipe) -> Stdio { - Stdio::Fd(pipe.into_fd()) - } -} - -impl From<File> for Stdio { - fn from(file: File) -> Stdio { - Stdio::Fd(file.into_fd()) - } -} - -impl ChildStdio { - fn fd(&self) -> Option<usize> { - match *self { - ChildStdio::Inherit => None, - ChildStdio::Explicit(fd) => Some(fd), - ChildStdio::Owned(ref fd) => Some(fd.raw()), - } - } -} - -impl fmt::Debug for Command { - fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - write!(f, "{:?}", self.program)?; - for arg in &self.args { - write!(f, " {:?}", arg)?; - } - Ok(()) - } -} - -//////////////////////////////////////////////////////////////////////////////// -// Processes -//////////////////////////////////////////////////////////////////////////////// - -/// Unix exit statuses -#[derive(PartialEq, Eq, Clone, Copy, Debug)] -pub struct ExitStatus(i32); - -impl ExitStatus { - fn exited(&self) -> bool { - self.0 & 0x7F == 0 - } - - pub fn success(&self) -> bool { - self.code() == Some(0) - } - - pub fn code(&self) -> Option<i32> { - if self.exited() { - Some((self.0 >> 8) & 0xFF) - } else { - None - } - } - - pub fn signal(&self) -> Option<i32> { - if !self.exited() { - Some(self.0 & 0x7F) - } else { - None - } - } -} - -impl From<i32> for ExitStatus { - fn from(a: i32) -> ExitStatus { - ExitStatus(a) - } -} - -impl fmt::Display for ExitStatus { - fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - if let Some(code) = self.code() { - write!(f, "exit code: {}", code) - } else { - let signal = self.signal().unwrap(); - write!(f, "signal: {}", signal) - } - } -} - -#[derive(PartialEq, Eq, Clone, Copy, Debug)] -pub struct ExitCode(u8); - -impl ExitCode { - pub const SUCCESS: ExitCode = ExitCode(EXIT_SUCCESS as _); - pub const FAILURE: ExitCode = ExitCode(EXIT_FAILURE as _); - - pub fn as_i32(&self) -> i32 { - self.0 as i32 - } -} - -/// The unique id of the process (this should never be negative). -pub struct Process { - pid: usize, - status: Option<ExitStatus>, -} - -impl Process { - pub fn id(&self) -> u32 { - self.pid as u32 - } - - pub fn kill(&mut self) -> io::Result<()> { - // If we've already waited on this process then the pid can be recycled - // and used for another process, and we probably shouldn't be killing - // random processes, so just return an error. - if self.status.is_some() { - Err(Error::new(ErrorKind::InvalidInput, - "invalid argument: can't kill an exited process")) - } else { - cvt(syscall::kill(self.pid, syscall::SIGKILL))?; - Ok(()) - } - } - - pub fn wait(&mut self) -> io::Result<ExitStatus> { - if let Some(status) = self.status { - return Ok(status) - } - let mut status = 0; - cvt(syscall::waitpid(self.pid, &mut status, 0))?; - self.status = Some(ExitStatus(status as i32)); - Ok(ExitStatus(status as i32)) - } - - pub fn try_wait(&mut self) -> io::Result<Option<ExitStatus>> { - if let Some(status) = self.status { - return Ok(Some(status)) - } - let mut status = 0; - let pid = cvt(syscall::waitpid(self.pid, &mut status, syscall::WNOHANG))?; - if pid == 0 { - Ok(None) - } else { - self.status = Some(ExitStatus(status as i32)); - Ok(Some(ExitStatus(status as i32))) - } - } -} |