diff --git a/src/libstd/build.rs b/src/libstd/build.rs index 72cd6e4830bca..1087d1f24471b 100644 --- a/src/libstd/build.rs +++ b/src/libstd/build.rs @@ -60,6 +60,8 @@ fn main() { println!("cargo:rustc-link-lib=shell32"); } else if target.contains("fuchsia") { println!("cargo:rustc-link-lib=magenta"); + println!("cargo:rustc-link-lib=mxio"); + println!("cargo:rustc-link-lib=launchpad"); // for std::process } } diff --git a/src/libstd/sys/unix/fd.rs b/src/libstd/sys/unix/fd.rs index 41bb96fed16cb..61eb60da486c9 100644 --- a/src/libstd/sys/unix/fd.rs +++ b/src/libstd/sys/unix/fd.rs @@ -110,6 +110,7 @@ impl FileDesc { #[cfg(not(any(target_env = "newlib", target_os = "solaris", target_os = "emscripten", + target_os = "fuchsia", target_os = "haiku")))] pub fn set_cloexec(&self) -> io::Result<()> { unsafe { @@ -120,6 +121,7 @@ impl FileDesc { #[cfg(any(target_env = "newlib", target_os = "solaris", target_os = "emscripten", + target_os = "fuchsia", target_os = "haiku"))] pub fn set_cloexec(&self) -> io::Result<()> { unsafe { diff --git a/src/libstd/sys/unix/pipe.rs b/src/libstd/sys/unix/pipe.rs index ffe8032e46055..a8ed415b7f47f 100644 --- a/src/libstd/sys/unix/pipe.rs +++ b/src/libstd/sys/unix/pipe.rs @@ -77,6 +77,7 @@ pub fn read2(p1: AnonPipe, v1: &mut Vec, p2: AnonPipe, v2: &mut Vec) -> io::Result<()> { + // Set both pipes into nonblocking mode as we're gonna be reading from both // in the `select` loop below, and we wouldn't want one to block the other! let p1 = p1.into_fd(); diff --git a/src/libstd/sys/unix/process/magenta.rs b/src/libstd/sys/unix/process/magenta.rs new file mode 100644 index 0000000000000..319fbce35cd7b --- /dev/null +++ b/src/libstd/sys/unix/process/magenta.rs @@ -0,0 +1,191 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![allow(non_camel_case_types)] + +use convert::TryInto; +use io; +use os::raw::c_char; +use u64; + +use libc::{c_int, c_void}; + +pub type mx_handle_t = i32; +pub type mx_vaddr_t = usize; +pub type mx_rights_t = u32; +pub type mx_status_t = i32; + +pub type mx_size_t = usize; +pub type mx_ssize_t = isize; + +pub const MX_HANDLE_INVALID: mx_handle_t = 0; + +pub type mx_time_t = u64; +pub const MX_TIME_INFINITE : mx_time_t = u64::MAX; + +pub type mx_signals_t = u32; + +pub const MX_OBJECT_SIGNAL_3 : mx_signals_t = 1 << 3; + +pub const MX_TASK_TERMINATED : mx_signals_t = MX_OBJECT_SIGNAL_3; + +pub const MX_RIGHT_SAME_RIGHTS : mx_rights_t = 1 << 31; + +pub type mx_object_info_topic_t = u32; + +pub const MX_INFO_PROCESS : mx_object_info_topic_t = 3; + +pub const MX_HND_TYPE_JOB: u32 = 6; + +pub fn mx_cvt(t: T) -> io::Result where T: TryInto+Copy { + if let Ok(status) = TryInto::try_into(t) { + if status < 0 { + Err(io::Error::from_raw_os_error(status)) + } else { + Ok(t) + } + } else { + Err(io::Error::last_os_error()) + } +} + +// Safe wrapper around mx_handle_t +pub struct Handle { + raw: mx_handle_t, +} + +impl Handle { + pub fn new(raw: mx_handle_t) -> Handle { + Handle { + raw: raw, + } + } + + pub fn raw(&self) -> mx_handle_t { + self.raw + } +} + +impl Drop for Handle { + fn drop(&mut self) { + unsafe { mx_cvt(mx_handle_close(self.raw)).expect("Failed to close mx_handle_t"); } + } +} + +// Common MX_INFO header +#[derive(Default)] +#[repr(C)] +pub struct mx_info_header_t { + pub topic: u32, // identifies the info struct + pub avail_topic_size: u16, // “native” size of the struct + pub topic_size: u16, // size of the returned struct (<=topic_size) + pub avail_count: u32, // number of records the kernel has + pub count: u32, // number of records returned (limited by buffer size) +} + +#[derive(Default)] +#[repr(C)] +pub struct mx_record_process_t { + pub return_code: c_int, +} + +// Returned for topic MX_INFO_PROCESS +#[derive(Default)] +#[repr(C)] +pub struct mx_info_process_t { + pub hdr: mx_info_header_t, + pub rec: mx_record_process_t, +} + +extern { + pub fn mx_task_kill(handle: mx_handle_t) -> mx_status_t; + + pub fn mx_handle_close(handle: mx_handle_t) -> mx_status_t; + + pub fn mx_handle_duplicate(handle: mx_handle_t, rights: mx_rights_t, + out: *const mx_handle_t) -> mx_handle_t; + + pub fn mx_handle_wait_one(handle: mx_handle_t, signals: mx_signals_t, timeout: mx_time_t, + pending: *mut mx_signals_t) -> mx_status_t; + + pub fn mx_object_get_info(handle: mx_handle_t, topic: u32, buffer: *mut c_void, + buffer_size: mx_size_t, actual_size: *mut mx_size_t, + avail: *mut mx_size_t) -> mx_status_t; +} + +// Handle Info entries associate a type and optional +// argument with each handle included in the process +// arguments message. +pub fn mx_hnd_info(hnd_type: u32, arg: u32) -> u32 { + (hnd_type & 0xFFFF) | ((arg & 0xFFFF) << 16) +} + +extern { + pub fn mxio_get_startup_handle(id: u32) -> mx_handle_t; +} + +// From `enum special_handles` in system/ulib/launchpad/launchpad.c +#[allow(unused)] pub const HND_LOADER_SVC: usize = 0; +// HND_EXEC_VMO = 1 +#[allow(unused)] pub const HND_SPECIAL_COUNT: usize = 2; + +#[repr(C)] +pub struct launchpad_t { + argc: u32, + envc: u32, + args: *const c_char, + args_len: usize, + env: *const c_char, + env_len: usize, + + handles: *mut mx_handle_t, + handles_info: *mut u32, + handle_count: usize, + handle_alloc: usize, + + entry: mx_vaddr_t, + base: mx_vaddr_t, + vdso_base: mx_vaddr_t, + + stack_size: usize, + + special_handles: [mx_handle_t; HND_SPECIAL_COUNT], + loader_message: bool, +} + +extern { + pub fn launchpad_create(job: mx_handle_t, name: *const c_char, + lp: *mut *mut launchpad_t) -> mx_status_t; + + pub fn launchpad_start(lp: *mut launchpad_t) -> mx_status_t; + + pub fn launchpad_destroy(lp: *mut launchpad_t); + + pub fn launchpad_arguments(lp: *mut launchpad_t, argc: c_int, + argv: *const *const c_char) -> mx_status_t; + + pub fn launchpad_environ(lp: *mut launchpad_t, envp: *const *const c_char) -> mx_status_t; + + pub fn launchpad_clone_mxio_root(lp: *mut launchpad_t) -> mx_status_t; + + pub fn launchpad_clone_mxio_cwd(lp: *mut launchpad_t) -> mx_status_t; + + pub fn launchpad_clone_fd(lp: *mut launchpad_t, fd: c_int, target_fd: c_int) -> mx_status_t; + + pub fn launchpad_transfer_fd(lp: *mut launchpad_t, fd: c_int, target_fd: c_int) -> mx_status_t; + + pub fn launchpad_elf_load(lp: *mut launchpad_t, vmo: mx_handle_t) -> mx_status_t; + + pub fn launchpad_add_vdso_vmo(lp: *mut launchpad_t) -> mx_status_t; + + pub fn launchpad_load_vdso(lp: *mut launchpad_t, vmo: mx_handle_t) -> mx_status_t; + + pub fn launchpad_vmo_from_file(filename: *const c_char) -> mx_handle_t; +} diff --git a/src/libstd/sys/unix/process/mod.rs b/src/libstd/sys/unix/process/mod.rs new file mode 100644 index 0000000000000..b50384d8eee33 --- /dev/null +++ b/src/libstd/sys/unix/process/mod.rs @@ -0,0 +1,22 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +pub use self::process_common::{Command, ExitStatus, Stdio, StdioPipes}; +pub use self::process_inner::Process; + +mod process_common; +#[cfg(not(target_os = "fuchsia"))] +#[path = "process_unix.rs"] +mod process_inner; +#[cfg(target_os = "fuchsia")] +#[path = "process_fuchsia.rs"] +mod process_inner; +#[cfg(target_os = "fuchsia")] +mod magenta; diff --git a/src/libstd/sys/unix/process.rs b/src/libstd/sys/unix/process/process_common.rs similarity index 59% rename from src/libstd/sys/unix/process.rs rename to src/libstd/sys/unix/process/process_common.rs index dafc11d9cc8e9..3497b266340e4 100644 --- a/src/libstd/sys/unix/process.rs +++ b/src/libstd/sys/unix/process/process_common.rs @@ -1,4 +1,4 @@ -// Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT +// 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. // @@ -14,14 +14,12 @@ use collections::hash_map::{HashMap, Entry}; use env; use ffi::{OsString, OsStr, CString, CStr}; use fmt; -use io::{self, Error, ErrorKind}; -use libc::{self, pid_t, c_int, gid_t, uid_t, c_char}; -use mem; +use io; +use libc::{self, c_int, gid_t, uid_t, c_char}; use ptr; use sys::fd::FileDesc; use sys::fs::{File, OpenOptions}; use sys::pipe::{self, AnonPipe}; -use sys::{self, cvt, cvt_r}; //////////////////////////////////////////////////////////////////////////////// // Command @@ -71,13 +69,13 @@ pub struct StdioPipes { // passed to do_exec() with configuration of what the child stdio should look // like -struct ChildPipes { - stdin: ChildStdio, - stdout: ChildStdio, - stderr: ChildStdio, +pub struct ChildPipes { + pub stdin: ChildStdio, + pub stdout: ChildStdio, + pub stderr: ChildStdio, } -enum ChildStdio { +pub enum ChildStdio { Inherit, Explicit(c_int), Owned(FileDesc), @@ -195,6 +193,33 @@ impl Command { self.gid = Some(id); } + pub fn saw_nul(&self) -> bool { + self.saw_nul + } + pub fn get_envp(&self) -> &Option> { + &self.envp + } + pub fn get_argv(&self) -> &Vec<*const c_char> { + &self.argv + } + + #[allow(dead_code)] + pub fn get_cwd(&self) -> &Option { + &self.cwd + } + #[allow(dead_code)] + pub fn get_uid(&self) -> Option { + self.uid + } + #[allow(dead_code)] + pub fn get_gid(&self) -> Option { + self.gid + } + + pub fn get_closures(&mut self) -> &mut Vec io::Result<()> + Send + Sync>> { + &mut self.closures + } + pub fn before_exec(&mut self, f: Box io::Result<()> + Send + Sync>) { self.closures.push(f); @@ -203,200 +228,16 @@ impl Command { 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) = sys::pipe::anon_pipe()?; - - let pid = unsafe { - match cvt(libc::fork())? { - 0 => { - drop(input); - let err = self.do_exec(theirs); - let errno = err.raw_os_error().unwrap_or(libc::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()); - libc::_exit(1) - } - 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 OSX 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 libc::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.stdin.fd() { - t!(cvt_r(|| libc::dup2(fd, libc::STDIN_FILENO))); - } - if let Some(fd) = stdio.stdout.fd() { - t!(cvt_r(|| libc::dup2(fd, libc::STDOUT_FILENO))); - } - if let Some(fd) = stdio.stderr.fd() { - t!(cvt_r(|| libc::dup2(fd, libc::STDERR_FILENO))); - } - - if let Some(u) = self.gid { - t!(cvt(libc::setgid(u as gid_t))); - } - if let Some(u) = self.uid { - // When dropping privileges from root, the `setgroups` call - // will remove any extraneous groups. If we don't call this, - // then even though our uid has dropped, we may still have - // groups that enable us to do super-user things. This will - // fail if we aren't root, so don't bother checking the - // return value, this is just done as an optimistic - // privilege dropping function. - let _ = libc::setgroups(0, ptr::null()); - - t!(cvt(libc::setuid(u as uid_t))); - } - if let Some(ref cwd) = self.cwd { - t!(cvt(libc::chdir(cwd.as_ptr()))); - } - if let Some(ref envp) = self.envp { - *sys::os::environ() = envp.as_ptr(); - } - - // NaCl has no signal support. - if cfg!(not(any(target_os = "nacl", target_os = "emscripten"))) { - // Reset signal handling so the child process starts in a - // standardized state. libstd ignores SIGPIPE, and signal-handling - // libraries often set a mask. Child processes inherit ignored - // signals and the signal mask from their parent, but most - // UNIX programs do not reset these things on their own, so we - // need to clean things up now to avoid confusing the program - // we're about to run. - let mut set: libc::sigset_t = mem::uninitialized(); - t!(cvt(libc::sigemptyset(&mut set))); - t!(cvt(libc::pthread_sigmask(libc::SIG_SETMASK, &set, - ptr::null_mut()))); - let ret = super::signal(libc::SIGPIPE, libc::SIG_DFL); - if ret == libc::SIG_ERR { - return io::Error::last_os_error() - } - } - - for callback in self.closures.iter_mut() { - t!(callback()); - } - - libc::execvp(self.argv[0], self.argv.as_ptr()); - io::Error::last_os_error() - } - - - fn setup_io(&self, default: Stdio, needs_stdin: bool) + pub 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}; @@ -428,10 +269,12 @@ fn os2c(s: &OsStr, saw_nul: &mut bool) -> CString { } impl Stdio { - fn to_child_stdio(&self, readable: bool) + pub fn to_child_stdio(&self, readable: bool) -> io::Result<(ChildStdio, Option)> { match *self { - Stdio::Inherit => Ok((ChildStdio::Inherit, None)), + 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 @@ -473,7 +316,7 @@ impl Stdio { } impl ChildStdio { - fn fd(&self) -> Option { + pub fn fd(&self) -> Option { match *self { ChildStdio::Inherit => None, ChildStdio::Explicit(fd) => Some(fd), @@ -504,15 +347,15 @@ impl fmt::Debug for Command { } } -//////////////////////////////////////////////////////////////////////////////// -// Processes -//////////////////////////////////////////////////////////////////////////////// - /// Unix exit statuses #[derive(PartialEq, Eq, Clone, Copy, Debug)] pub struct ExitStatus(c_int); impl ExitStatus { + pub fn new(status: c_int) -> ExitStatus { + ExitStatus(status) + } + fn exited(&self) -> bool { unsafe { libc::WIFEXITED(self.0) } } @@ -555,40 +398,6 @@ impl fmt::Display for ExitStatus { } } -/// The unique id of the process (this should never be negative). -pub struct Process { - pid: pid_t, - status: Option, -} - -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(unsafe { libc::kill(self.pid, libc::SIGKILL) }).map(|_| ()) - } - } - - pub fn wait(&mut self) -> io::Result { - if let Some(status) = self.status { - return Ok(status) - } - let mut status = 0 as c_int; - cvt_r(|| unsafe { libc::waitpid(self.pid, &mut status, 0) })?; - self.status = Some(ExitStatus(status)); - Ok(ExitStatus(status)) - } -} - #[cfg(all(test, not(target_os = "emscripten")))] mod tests { use super::*; diff --git a/src/libstd/sys/unix/process/process_fuchsia.rs b/src/libstd/sys/unix/process/process_fuchsia.rs new file mode 100644 index 0000000000000..f0a42b127998c --- /dev/null +++ b/src/libstd/sys/unix/process/process_fuchsia.rs @@ -0,0 +1,174 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use io; +use libc; +use mem; +use ptr; + +use sys::process::magenta::{Handle, launchpad_t, mx_handle_t}; +use sys::process::process_common::*; + +//////////////////////////////////////////////////////////////////////////////// +// Command +//////////////////////////////////////////////////////////////////////////////// + +impl Command { + pub fn spawn(&mut self, default: Stdio, needs_stdin: bool) + -> io::Result<(Process, StdioPipes)> { + if self.saw_nul() { + return Err(io::Error::new(io::ErrorKind::InvalidInput, + "nul byte found in provided data")); + } + + let (ours, theirs) = self.setup_io(default, needs_stdin)?; + + let (launchpad, process_handle) = unsafe { self.do_exec(theirs)? }; + + Ok((Process { launchpad: launchpad, handle: Handle::new(process_handle) }, ours)) + } + + pub fn exec(&mut self, default: Stdio) -> io::Error { + if self.saw_nul() { + return io::Error::new(io::ErrorKind::InvalidInput, + "nul byte found in provided data") + } + + match self.setup_io(default, true) { + Ok((_, _)) => { + // FIXME: This is tough because we don't support the exec syscalls + unimplemented!(); + }, + Err(e) => e, + } + } + + unsafe fn do_exec(&mut self, stdio: ChildPipes) + -> io::Result<(*mut launchpad_t, mx_handle_t)> { + use sys::process::magenta::*; + + let job_handle = mxio_get_startup_handle(mx_hnd_info(MX_HND_TYPE_JOB, 0)); + let envp = match *self.get_envp() { + Some(ref envp) => envp.as_ptr(), + None => ptr::null(), + }; + + // To make sure launchpad_destroy gets called on the launchpad if this function fails + struct LaunchpadDestructor(*mut launchpad_t); + impl Drop for LaunchpadDestructor { + fn drop(&mut self) { unsafe { launchpad_destroy(self.0); } } + } + + let mut launchpad: *mut launchpad_t = ptr::null_mut(); + let launchpad_destructor = LaunchpadDestructor(launchpad); + + // Duplicate the job handle + let mut job_copy: mx_handle_t = MX_HANDLE_INVALID; + mx_cvt(mx_handle_duplicate(job_handle, MX_RIGHT_SAME_RIGHTS, &mut job_copy))?; + // Create a launchpad + mx_cvt(launchpad_create(job_copy, self.get_argv()[0], &mut launchpad))?; + // Set the process argv + mx_cvt(launchpad_arguments(launchpad, self.get_argv().len() as i32 - 1, + self.get_argv().as_ptr()))?; + // Setup the environment vars + mx_cvt(launchpad_environ(launchpad, envp))?; + mx_cvt(launchpad_add_vdso_vmo(launchpad))?; + mx_cvt(launchpad_clone_mxio_root(launchpad))?; + // Load the executable + mx_cvt(launchpad_elf_load(launchpad, launchpad_vmo_from_file(self.get_argv()[0])))?; + mx_cvt(launchpad_load_vdso(launchpad, MX_HANDLE_INVALID))?; + mx_cvt(launchpad_clone_mxio_cwd(launchpad))?; + + // Clone stdin, stdout, and stderr + if let Some(fd) = stdio.stdin.fd() { + launchpad_transfer_fd(launchpad, fd, 0); + } else { + launchpad_clone_fd(launchpad, 0, 0); + } + if let Some(fd) = stdio.stdout.fd() { + launchpad_transfer_fd(launchpad, fd, 1); + } else { + launchpad_clone_fd(launchpad, 1, 1); + } + if let Some(fd) = stdio.stderr.fd() { + launchpad_transfer_fd(launchpad, fd, 2); + } else { + launchpad_clone_fd(launchpad, 2, 2); + } + + // We don't want FileDesc::drop to be called on any stdio. It would close their fds. The + // fds will be closed once the child process finishes. + mem::forget(stdio); + + for callback in self.get_closures().iter_mut() { + callback()?; + } + + let process_handle = mx_cvt(launchpad_start(launchpad))?; + + // Successfully started the launchpad + mem::forget(launchpad_destructor); + + Ok((launchpad, process_handle)) + } +} + +//////////////////////////////////////////////////////////////////////////////// +// Processes +//////////////////////////////////////////////////////////////////////////////// + +pub struct Process { + launchpad: *mut launchpad_t, + handle: Handle, +} + +impl Process { + pub fn id(&self) -> u32 { + self.handle.raw() as u32 + } + + pub fn kill(&mut self) -> io::Result<()> { + use sys::process::magenta::*; + + unsafe { mx_cvt(mx_task_kill(self.handle.raw()))?; } + + Ok(()) + } + + pub fn wait(&mut self) -> io::Result { + use default::Default; + use sys::process::magenta::*; + + let mut proc_info: mx_info_process_t = Default::default(); + let mut actual: mx_size_t = 0; + let mut avail: mx_size_t = 0; + + unsafe { + mx_cvt(mx_handle_wait_one(self.handle.raw(), MX_TASK_TERMINATED, + MX_TIME_INFINITE, ptr::null_mut()))?; + mx_cvt(mx_object_get_info(self.handle.raw(), MX_INFO_PROCESS, + &mut proc_info as *mut _ as *mut libc::c_void, + mem::size_of::(), &mut actual, + &mut avail))?; + } + if actual != 1 { + return Err(io::Error::new(io::ErrorKind::InvalidData, + "Failed to get exit status of process")); + } + Ok(ExitStatus::new(proc_info.rec.return_code)) + } +} + +impl Drop for Process { + fn drop(&mut self) { + use sys::process::magenta::launchpad_destroy; + unsafe { launchpad_destroy(self.launchpad); } + } +} diff --git a/src/libstd/sys/unix/process/process_unix.rs b/src/libstd/sys/unix/process/process_unix.rs new file mode 100644 index 0000000000000..aa42672202559 --- /dev/null +++ b/src/libstd/sys/unix/process/process_unix.rs @@ -0,0 +1,250 @@ +// Copyright 2014-2015 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use io::{self, Error, ErrorKind}; +use libc::{self, c_int, gid_t, pid_t, uid_t}; +use mem; +use ptr; + +use sys::cvt; +use sys::process::process_common::*; + +//////////////////////////////////////////////////////////////////////////////// +// Command +//////////////////////////////////////////////////////////////////////////////// + +impl Command { + pub fn spawn(&mut self, default: Stdio, needs_stdin: bool) + -> io::Result<(Process, StdioPipes)> { + use sys; + + 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) = sys::pipe::anon_pipe()?; + + let pid = unsafe { + match cvt(libc::fork())? { + 0 => { + drop(input); + let err = self.do_exec(theirs); + let errno = err.raw_os_error().unwrap_or(libc::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()); + libc::_exit(1) + } + 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 OSX 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 libc::exit) + unsafe fn do_exec(&mut self, stdio: ChildPipes) -> io::Error { + use sys::{self, cvt_r}; + + macro_rules! t { + ($e:expr) => (match $e { + Ok(e) => e, + Err(e) => return e, + }) + } + + if let Some(fd) = stdio.stdin.fd() { + t!(cvt_r(|| libc::dup2(fd, libc::STDIN_FILENO))); + } + if let Some(fd) = stdio.stdout.fd() { + t!(cvt_r(|| libc::dup2(fd, libc::STDOUT_FILENO))); + } + if let Some(fd) = stdio.stderr.fd() { + t!(cvt_r(|| libc::dup2(fd, libc::STDERR_FILENO))); + } + + if let Some(u) = self.get_gid() { + t!(cvt(libc::setgid(u as gid_t))); + } + if let Some(u) = self.get_uid() { + // When dropping privileges from root, the `setgroups` call + // will remove any extraneous groups. If we don't call this, + // then even though our uid has dropped, we may still have + // groups that enable us to do super-user things. This will + // fail if we aren't root, so don't bother checking the + // return value, this is just done as an optimistic + // privilege dropping function. + let _ = libc::setgroups(0, ptr::null()); + + t!(cvt(libc::setuid(u as uid_t))); + } + if let Some(ref cwd) = *self.get_cwd() { + t!(cvt(libc::chdir(cwd.as_ptr()))); + } + if let Some(ref envp) = *self.get_envp() { + *sys::os::environ() = envp.as_ptr(); + } + + // NaCl has no signal support. + if cfg!(not(any(target_os = "nacl", target_os = "emscripten"))) { + // Reset signal handling so the child process starts in a + // standardized state. libstd ignores SIGPIPE, and signal-handling + // libraries often set a mask. Child processes inherit ignored + // signals and the signal mask from their parent, but most + // UNIX programs do not reset these things on their own, so we + // need to clean things up now to avoid confusing the program + // we're about to run. + let mut set: libc::sigset_t = mem::uninitialized(); + t!(cvt(libc::sigemptyset(&mut set))); + t!(cvt(libc::pthread_sigmask(libc::SIG_SETMASK, &set, + ptr::null_mut()))); + let ret = sys::signal(libc::SIGPIPE, libc::SIG_DFL); + if ret == libc::SIG_ERR { + return io::Error::last_os_error() + } + } + + for callback in self.get_closures().iter_mut() { + t!(callback()); + } + + libc::execvp(self.get_argv()[0], self.get_argv().as_ptr()); + io::Error::last_os_error() + } +} + +//////////////////////////////////////////////////////////////////////////////// +// Processes +//////////////////////////////////////////////////////////////////////////////// + +/// The unique id of the process (this should never be negative). +pub struct Process { + pid: pid_t, + status: Option, +} + +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(unsafe { libc::kill(self.pid, libc::SIGKILL) }).map(|_| ()) + } + } + pub fn wait(&mut self) -> io::Result { + use sys::cvt_r; + if let Some(status) = self.status { + return Ok(status) + } + let mut status = 0 as c_int; + cvt_r(|| unsafe { libc::waitpid(self.pid, &mut status, 0) })?; + self.status = Some(ExitStatus::new(status)); + Ok(ExitStatus::new(status)) + } +}