+++ /dev/null
-// Copyright 2012-2014 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 libc::{pid_t, c_void, c_int};
-use libc;
-use std::c_str::CString;
-use std::io;
-use std::mem;
-use std::os;
-use std::ptr;
-use std::rt::rtio::{ProcessConfig, IoResult, IoError};
-use std::rt::rtio;
-
-use super::file;
-use super::util;
-
-#[cfg(windows)] use std::io::fs::PathExtensions;
-#[cfg(windows)] use std::string::String;
-#[cfg(unix)] use super::c;
-#[cfg(unix)] use super::retry;
-#[cfg(unix)] use io::helper_thread::Helper;
-
-#[cfg(unix)]
-helper_init!(static HELPER: Helper<Req>)
-
-/**
- * A value representing a child process.
- *
- * The lifetime of this value is linked to the lifetime of the actual
- * process - the Process destructor calls self.finish() which waits
- * for the process to terminate.
- */
-pub struct Process {
- /// The unique id of the process (this should never be negative).
- pid: pid_t,
-
- /// A handle to the process - on unix this will always be NULL, but on
- /// windows it will be a HANDLE to the process, which will prevent the
- /// pid being re-used until the handle is closed.
- handle: *mut (),
-
- /// None until finish() is called.
- exit_code: Option<rtio::ProcessExit>,
-
- /// Manually delivered signal
- exit_signal: Option<int>,
-
- /// Deadline after which wait() will return
- deadline: u64,
-}
-
-#[cfg(unix)]
-enum Req {
- NewChild(libc::pid_t, Sender<rtio::ProcessExit>, u64),
-}
-
-impl Process {
- /// Creates a new process using native process-spawning abilities provided
- /// by the OS. Operations on this process will be blocking instead of using
- /// the runtime for sleeping just this current task.
- pub fn spawn(cfg: ProcessConfig)
- -> IoResult<(Process, Vec<Option<file::FileDesc>>)>
- {
- // right now we only handle stdin/stdout/stderr.
- if cfg.extra_io.len() > 0 {
- return Err(super::unimpl());
- }
-
- fn get_io(io: rtio::StdioContainer,
- ret: &mut Vec<Option<file::FileDesc>>)
- -> IoResult<Option<file::FileDesc>>
- {
- match io {
- rtio::Ignored => { ret.push(None); Ok(None) }
- rtio::InheritFd(fd) => {
- ret.push(None);
- Ok(Some(file::FileDesc::new(fd, false)))
- }
- rtio::CreatePipe(readable, _writable) => {
- let (reader, writer) = try!(pipe());
- let (theirs, ours) = if readable {
- (reader, writer)
- } else {
- (writer, reader)
- };
- ret.push(Some(ours));
- Ok(Some(theirs))
- }
- }
- }
-
- let mut ret_io = Vec::new();
- let res = spawn_process_os(cfg,
- try!(get_io(cfg.stdin, &mut ret_io)),
- try!(get_io(cfg.stdout, &mut ret_io)),
- try!(get_io(cfg.stderr, &mut ret_io)));
-
- match res {
- Ok(res) => {
- let p = Process {
- pid: res.pid,
- handle: res.handle,
- exit_code: None,
- exit_signal: None,
- deadline: 0,
- };
- Ok((p, ret_io))
- }
- Err(e) => Err(e)
- }
- }
-
- pub fn kill(pid: libc::pid_t, signum: int) -> IoResult<()> {
- unsafe { killpid(pid, signum) }
- }
-}
-
-impl rtio::RtioProcess for Process {
- fn id(&self) -> pid_t { self.pid }
-
- fn set_timeout(&mut self, timeout: Option<u64>) {
- self.deadline = timeout.map(|i| i + ::io::timer::now()).unwrap_or(0);
- }
-
- fn wait(&mut self) -> IoResult<rtio::ProcessExit> {
- match self.exit_code {
- Some(code) => Ok(code),
- None => {
- let code = try!(waitpid(self.pid, self.deadline));
- // On windows, waitpid will never return a signal. If a signal
- // was successfully delivered to the process, however, we can
- // consider it as having died via a signal.
- let code = match self.exit_signal {
- None => code,
- Some(signal) if cfg!(windows) => rtio::ExitSignal(signal),
- Some(..) => code,
- };
- self.exit_code = Some(code);
- Ok(code)
- }
- }
- }
-
- fn kill(&mut self, signum: int) -> IoResult<()> {
- #[cfg(unix)] use libc::EINVAL as ERROR;
- #[cfg(windows)] use libc::ERROR_NOTHING_TO_TERMINATE as ERROR;
-
- // On Linux (and possibly other unices), a process that has exited will
- // continue to accept signals because it is "defunct". The delivery of
- // signals will only fail once the child has been reaped. For this
- // reason, if the process hasn't exited yet, then we attempt to collect
- // their status with WNOHANG.
- if self.exit_code.is_none() {
- match waitpid_nowait(self.pid) {
- Some(code) => { self.exit_code = Some(code); }
- None => {}
- }
- }
-
- // if the process has finished, and therefore had waitpid called,
- // and we kill it, then on unix we might ending up killing a
- // newer process that happens to have the same (re-used) id
- match self.exit_code {
- Some(..) => return Err(IoError {
- code: ERROR as uint,
- extra: 0,
- detail: Some("can't kill an exited process".to_string()),
- }),
- None => {}
- }
-
- // A successfully delivered signal that isn't 0 (just a poll for being
- // alive) is recorded for windows (see wait())
- match unsafe { killpid(self.pid, signum) } {
- Ok(()) if signum == 0 => Ok(()),
- Ok(()) => { self.exit_signal = Some(signum); Ok(()) }
- Err(e) => Err(e),
- }
- }
-}
-
-impl Drop for Process {
- fn drop(&mut self) {
- free_handle(self.handle);
- }
-}
-
-pub fn pipe() -> IoResult<(file::FileDesc, file::FileDesc)> {
- #[cfg(unix)] use libc::EMFILE as ERROR;
- #[cfg(windows)] use libc::WSAEMFILE as ERROR;
- struct Closer { fd: libc::c_int }
-
- let os::Pipe { reader, writer } = match unsafe { os::pipe() } {
- Ok(p) => p,
- Err(io::IoError { detail, .. }) => return Err(IoError {
- code: ERROR as uint,
- extra: 0,
- detail: detail,
- })
- };
- let mut reader = Closer { fd: reader };
- let mut writer = Closer { fd: writer };
-
- let native_reader = file::FileDesc::new(reader.fd, true);
- reader.fd = -1;
- let native_writer = file::FileDesc::new(writer.fd, true);
- writer.fd = -1;
- return Ok((native_reader, native_writer));
-
- impl Drop for Closer {
- fn drop(&mut self) {
- if self.fd != -1 {
- let _ = unsafe { libc::close(self.fd) };
- }
- }
- }
-}
-
-#[cfg(windows)]
-unsafe fn killpid(pid: pid_t, signal: int) -> IoResult<()> {
- let handle = libc::OpenProcess(libc::PROCESS_TERMINATE |
- libc::PROCESS_QUERY_INFORMATION,
- libc::FALSE, pid as libc::DWORD);
- if handle.is_null() {
- return Err(super::last_error())
- }
- let ret = match signal {
- // test for existence on signal 0
- 0 => {
- let mut status = 0;
- let ret = libc::GetExitCodeProcess(handle, &mut status);
- if ret == 0 {
- Err(super::last_error())
- } else if status != libc::STILL_ACTIVE {
- Err(IoError {
- code: libc::ERROR_NOTHING_TO_TERMINATE as uint,
- extra: 0,
- detail: None,
- })
- } else {
- Ok(())
- }
- }
- 15 | 9 => { // sigterm or sigkill
- let ret = libc::TerminateProcess(handle, 1);
- super::mkerr_winbool(ret)
- }
- _ => Err(IoError {
- code: libc::ERROR_CALL_NOT_IMPLEMENTED as uint,
- extra: 0,
- detail: Some("unsupported signal on windows".to_string()),
- })
- };
- let _ = libc::CloseHandle(handle);
- return ret;
-}
-
-#[cfg(not(windows))]
-unsafe fn killpid(pid: pid_t, signal: int) -> IoResult<()> {
- let r = libc::funcs::posix88::signal::kill(pid, signal as c_int);
- super::mkerr_libc(r)
-}
-
-struct SpawnProcessResult {
- pid: pid_t,
- handle: *mut (),
-}
-
-#[cfg(windows)]
-fn spawn_process_os(cfg: ProcessConfig,
- in_fd: Option<file::FileDesc>,
- out_fd: Option<file::FileDesc>,
- err_fd: Option<file::FileDesc>)
- -> IoResult<SpawnProcessResult> {
- use libc::types::os::arch::extra::{DWORD, HANDLE, STARTUPINFO};
- use libc::consts::os::extra::{
- TRUE, FALSE,
- STARTF_USESTDHANDLES,
- INVALID_HANDLE_VALUE,
- DUPLICATE_SAME_ACCESS
- };
- use libc::funcs::extra::kernel32::{
- GetCurrentProcess,
- DuplicateHandle,
- CloseHandle,
- CreateProcessW
- };
- use libc::funcs::extra::msvcrt::get_osfhandle;
-
- use std::mem;
- use std::iter::Iterator;
- use std::str::StrPrelude;
-
- if cfg.gid.is_some() || cfg.uid.is_some() {
- return Err(IoError {
- code: libc::ERROR_CALL_NOT_IMPLEMENTED as uint,
- extra: 0,
- detail: Some("unsupported gid/uid requested on windows".to_string()),
- })
- }
-
- // To have the spawning semantics of unix/windows stay the same, we need to
- // read the *child's* PATH if one is provided. See #15149 for more details.
- let program = cfg.env.and_then(|env| {
- for &(ref key, ref v) in env.iter() {
- if b"PATH" != key.as_bytes_no_nul() { continue }
-
- // Split the value and test each path to see if the program exists.
- for path in os::split_paths(v.as_bytes_no_nul()).into_iter() {
- let path = path.join(cfg.program.as_bytes_no_nul())
- .with_extension(os::consts::EXE_EXTENSION);
- if path.exists() {
- return Some(path.to_c_str())
- }
- }
- break
- }
- None
- });
-
- unsafe {
- let mut si = zeroed_startupinfo();
- si.cb = mem::size_of::<STARTUPINFO>() as DWORD;
- si.dwFlags = STARTF_USESTDHANDLES;
-
- let cur_proc = GetCurrentProcess();
-
- // Similarly to unix, we don't actually leave holes for the stdio file
- // descriptors, but rather open up /dev/null equivalents. These
- // equivalents are drawn from libuv's windows process spawning.
- let set_fd = |fd: &Option<file::FileDesc>, slot: &mut HANDLE,
- is_stdin: bool| {
- match *fd {
- None => {
- let access = if is_stdin {
- libc::FILE_GENERIC_READ
- } else {
- libc::FILE_GENERIC_WRITE | libc::FILE_READ_ATTRIBUTES
- };
- let size = mem::size_of::<libc::SECURITY_ATTRIBUTES>();
- let mut sa = libc::SECURITY_ATTRIBUTES {
- nLength: size as libc::DWORD,
- lpSecurityDescriptor: ptr::null_mut(),
- bInheritHandle: 1,
- };
- let mut filename: Vec<u16> = "NUL".utf16_units().collect();
- filename.push(0);
- *slot = libc::CreateFileW(filename.as_ptr(),
- access,
- libc::FILE_SHARE_READ |
- libc::FILE_SHARE_WRITE,
- &mut sa,
- libc::OPEN_EXISTING,
- 0,
- ptr::null_mut());
- if *slot == INVALID_HANDLE_VALUE {
- return Err(super::last_error())
- }
- }
- Some(ref fd) => {
- let orig = get_osfhandle(fd.fd()) as HANDLE;
- if orig == INVALID_HANDLE_VALUE {
- return Err(super::last_error())
- }
- if DuplicateHandle(cur_proc, orig, cur_proc, slot,
- 0, TRUE, DUPLICATE_SAME_ACCESS) == FALSE {
- return Err(super::last_error())
- }
- }
- }
- Ok(())
- };
-
- try!(set_fd(&in_fd, &mut si.hStdInput, true));
- try!(set_fd(&out_fd, &mut si.hStdOutput, false));
- try!(set_fd(&err_fd, &mut si.hStdError, false));
-
- let cmd_str = make_command_line(program.as_ref().unwrap_or(cfg.program),
- cfg.args);
- let mut pi = zeroed_process_information();
- let mut create_err = None;
-
- // stolen from the libuv code.
- let mut flags = libc::CREATE_UNICODE_ENVIRONMENT;
- if cfg.detach {
- flags |= libc::DETACHED_PROCESS | libc::CREATE_NEW_PROCESS_GROUP;
- }
-
- with_envp(cfg.env, |envp| {
- with_dirp(cfg.cwd, |dirp| {
- let mut cmd_str: Vec<u16> = cmd_str.as_slice().utf16_units().collect();
- cmd_str.push(0);
- let created = CreateProcessW(ptr::null(),
- cmd_str.as_mut_ptr(),
- ptr::null_mut(),
- ptr::null_mut(),
- TRUE,
- flags, envp, dirp,
- &mut si, &mut pi);
- if created == FALSE {
- create_err = Some(super::last_error());
- }
- })
- });
-
- assert!(CloseHandle(si.hStdInput) != 0);
- assert!(CloseHandle(si.hStdOutput) != 0);
- assert!(CloseHandle(si.hStdError) != 0);
-
- match create_err {
- Some(err) => return Err(err),
- None => {}
- }
-
- // We close the thread handle because we don't care about keeping the
- // thread id valid, and we aren't keeping the thread handle around to be
- // able to close it later. We don't close the process handle however
- // because std::we want the process id to stay valid at least until the
- // calling code closes the process handle.
- assert!(CloseHandle(pi.hThread) != 0);
-
- Ok(SpawnProcessResult {
- pid: pi.dwProcessId as pid_t,
- handle: pi.hProcess as *mut ()
- })
- }
-}
-
-#[cfg(windows)]
-fn zeroed_startupinfo() -> libc::types::os::arch::extra::STARTUPINFO {
- libc::types::os::arch::extra::STARTUPINFO {
- cb: 0,
- lpReserved: ptr::null_mut(),
- lpDesktop: ptr::null_mut(),
- lpTitle: ptr::null_mut(),
- dwX: 0,
- dwY: 0,
- dwXSize: 0,
- dwYSize: 0,
- dwXCountChars: 0,
- dwYCountCharts: 0,
- dwFillAttribute: 0,
- dwFlags: 0,
- wShowWindow: 0,
- cbReserved2: 0,
- lpReserved2: ptr::null_mut(),
- hStdInput: libc::INVALID_HANDLE_VALUE,
- hStdOutput: libc::INVALID_HANDLE_VALUE,
- hStdError: libc::INVALID_HANDLE_VALUE,
- }
-}
-
-#[cfg(windows)]
-fn zeroed_process_information() -> libc::types::os::arch::extra::PROCESS_INFORMATION {
- libc::types::os::arch::extra::PROCESS_INFORMATION {
- hProcess: ptr::null_mut(),
- hThread: ptr::null_mut(),
- dwProcessId: 0,
- dwThreadId: 0
- }
-}
-
-#[cfg(windows)]
-fn make_command_line(prog: &CString, args: &[CString]) -> String {
- let mut cmd = String::new();
- append_arg(&mut cmd, prog.as_str()
- .expect("expected program name to be utf-8 encoded"));
- for arg in args.iter() {
- cmd.push(' ');
- append_arg(&mut cmd, arg.as_str()
- .expect("expected argument to be utf-8 encoded"));
- }
- return cmd;
-
- fn append_arg(cmd: &mut String, arg: &str) {
- // If an argument has 0 characters then we need to quote it to ensure
- // that it actually gets passed through on the command line or otherwise
- // it will be dropped entirely when parsed on the other end.
- let quote = arg.chars().any(|c| c == ' ' || c == '\t') || arg.len() == 0;
- if quote {
- cmd.push('"');
- }
- let argvec: Vec<char> = arg.chars().collect();
- for i in range(0u, argvec.len()) {
- append_char_at(cmd, argvec.as_slice(), i);
- }
- if quote {
- cmd.push('"');
- }
- }
-
- fn append_char_at(cmd: &mut String, arg: &[char], i: uint) {
- match arg[i] {
- '"' => {
- // Escape quotes.
- cmd.push_str("\\\"");
- }
- '\\' => {
- if backslash_run_ends_in_quote(arg, i) {
- // Double all backslashes that are in runs before quotes.
- cmd.push_str("\\\\");
- } else {
- // Pass other backslashes through unescaped.
- cmd.push('\\');
- }
- }
- c => {
- cmd.push(c);
- }
- }
- }
-
- fn backslash_run_ends_in_quote(s: &[char], mut i: uint) -> bool {
- while i < s.len() && s[i] == '\\' {
- i += 1;
- }
- return i < s.len() && s[i] == '"';
- }
-}
-
-#[cfg(unix)]
-fn spawn_process_os(cfg: ProcessConfig,
- in_fd: Option<file::FileDesc>,
- out_fd: Option<file::FileDesc>,
- err_fd: Option<file::FileDesc>)
- -> IoResult<SpawnProcessResult>
-{
- use libc::funcs::posix88::unistd::{fork, dup2, close, chdir, execvp};
- use libc::funcs::bsd44::getdtablesize;
- use io::c;
-
- mod rustrt {
- extern {
- pub fn rust_unset_sigprocmask();
- }
- }
-
- #[cfg(target_os = "macos")]
- unsafe fn set_environ(envp: *const c_void) {
- extern { fn _NSGetEnviron() -> *mut *const c_void; }
-
- *_NSGetEnviron() = envp;
- }
- #[cfg(not(target_os = "macos"))]
- unsafe fn set_environ(envp: *const c_void) {
- extern { static mut environ: *const c_void; }
- environ = envp;
- }
-
- unsafe fn set_cloexec(fd: c_int) {
- let ret = c::ioctl(fd, c::FIOCLEX);
- assert_eq!(ret, 0);
- }
-
- let dirp = cfg.cwd.map(|c| c.as_ptr()).unwrap_or(ptr::null());
-
- let cfg = unsafe {
- mem::transmute::<ProcessConfig,ProcessConfig<'static>>(cfg)
- };
-
- with_envp(cfg.env, proc(envp) {
- with_argv(cfg.program, cfg.args, proc(argv) unsafe {
- let (mut input, mut output) = try!(pipe());
-
- // We may use this in the child, so perform allocations before the
- // fork
- let devnull = "/dev/null".to_c_str();
-
- set_cloexec(output.fd());
-
- let pid = fork();
- if pid < 0 {
- return Err(super::last_error())
- } else if pid > 0 {
- drop(output);
- let mut bytes = [0, ..4];
- return match input.inner_read(bytes) {
- Ok(4) => {
- let errno = (bytes[0] as i32 << 24) |
- (bytes[1] as i32 << 16) |
- (bytes[2] as i32 << 8) |
- (bytes[3] as i32 << 0);
-
- Err(IoError {
- code: errno as uint,
- detail: None,
- extra: 0,
- })
- }
- Err(..) => {
- Ok(SpawnProcessResult {
- pid: pid,
- handle: ptr::null_mut()
- })
- }
- Ok(..) => panic!("short read on the cloexec pipe"),
- };
- }
- // 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)
- let _ = libc::close(input.fd());
-
- fn fail(output: &mut file::FileDesc) -> ! {
- let errno = os::errno();
- let bytes = [
- (errno >> 24) as u8,
- (errno >> 16) as u8,
- (errno >> 8) as u8,
- (errno >> 0) as u8,
- ];
- assert!(output.inner_write(bytes).is_ok());
- unsafe { libc::_exit(1) }
- }
-
- rustrt::rust_unset_sigprocmask();
-
- // If a stdio file descriptor is set to be ignored (via a -1 file
- // descriptor), then we don't actually close it, but rather open
- // up /dev/null into that file descriptor. Otherwise, the first file
- // descriptor opened up in the child would be numbered as one of the
- // stdio file descriptors, which is likely to wreak havoc.
- let setup = |src: Option<file::FileDesc>, dst: c_int| {
- let src = match src {
- None => {
- let flags = if dst == libc::STDIN_FILENO {
- libc::O_RDONLY
- } else {
- libc::O_RDWR
- };
- libc::open(devnull.as_ptr(), flags, 0)
- }
- Some(obj) => {
- let fd = obj.fd();
- // Leak the memory and the file descriptor. We're in the
- // child now an all our resources are going to be
- // cleaned up very soon
- mem::forget(obj);
- fd
- }
- };
- src != -1 && retry(|| dup2(src, dst)) != -1
- };
-
- if !setup(in_fd, libc::STDIN_FILENO) { fail(&mut output) }
- if !setup(out_fd, libc::STDOUT_FILENO) { fail(&mut output) }
- if !setup(err_fd, libc::STDERR_FILENO) { fail(&mut output) }
-
- // close all other fds
- for fd in range(3, getdtablesize()).rev() {
- if fd != output.fd() {
- let _ = close(fd as c_int);
- }
- }
-
- match cfg.gid {
- Some(u) => {
- if libc::setgid(u as libc::gid_t) != 0 {
- fail(&mut output);
- }
- }
- None => {}
- }
- match cfg.uid {
- Some(u) => {
- // 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.
- extern {
- fn setgroups(ngroups: libc::c_int,
- ptr: *const libc::c_void) -> libc::c_int;
- }
- let _ = setgroups(0, 0 as *const libc::c_void);
-
- if libc::setuid(u as libc::uid_t) != 0 {
- fail(&mut output);
- }
- }
- None => {}
- }
- if cfg.detach {
- // Don't check the error of setsid because it fails if we're the
- // process leader already. We just forked so it shouldn't return
- // error, but ignore it anyway.
- let _ = libc::setsid();
- }
- if !dirp.is_null() && chdir(dirp) == -1 {
- fail(&mut output);
- }
- if !envp.is_null() {
- set_environ(envp);
- }
- let _ = execvp(*argv, argv as *mut _);
- fail(&mut output);
- })
- })
-}
-
-#[cfg(unix)]
-fn with_argv<T>(prog: &CString, args: &[CString],
- cb: proc(*const *const libc::c_char) -> T) -> T {
- let mut ptrs: Vec<*const libc::c_char> = Vec::with_capacity(args.len()+1);
-
- // Convert the CStrings into an array of pointers. Note: the
- // lifetime of the various CStrings involved is guaranteed to be
- // larger than the lifetime of our invocation of cb, but this is
- // technically unsafe as the callback could leak these pointers
- // out of our scope.
- ptrs.push(prog.as_ptr());
- ptrs.extend(args.iter().map(|tmp| tmp.as_ptr()));
-
- // Add a terminating null pointer (required by libc).
- ptrs.push(ptr::null());
-
- cb(ptrs.as_ptr())
-}
-
-#[cfg(unix)]
-fn with_envp<T>(env: Option<&[(&CString, &CString)]>,
- cb: proc(*const c_void) -> T) -> T {
- // On posixy systems we can pass a char** for envp, which is a
- // null-terminated array of "k=v\0" strings. Since we must create
- // these strings locally, yet expose a raw pointer to them, we
- // create a temporary vector to own the CStrings that outlives the
- // call to cb.
- match env {
- Some(env) => {
- let mut tmps = Vec::with_capacity(env.len());
-
- for pair in env.iter() {
- let mut kv = Vec::new();
- kv.push_all(pair.ref0().as_bytes_no_nul());
- kv.push('=' as u8);
- kv.push_all(pair.ref1().as_bytes()); // includes terminal \0
- tmps.push(kv);
- }
-
- // As with `with_argv`, this is unsafe, since cb could leak the pointers.
- let mut ptrs: Vec<*const libc::c_char> =
- tmps.iter()
- .map(|tmp| tmp.as_ptr() as *const libc::c_char)
- .collect();
- ptrs.push(ptr::null());
-
- cb(ptrs.as_ptr() as *const c_void)
- }
- _ => cb(ptr::null())
- }
-}
-
-#[cfg(windows)]
-fn with_envp<T>(env: Option<&[(&CString, &CString)]>, cb: |*mut c_void| -> T) -> T {
- // On Windows we pass an "environment block" which is not a char**, but
- // rather a concatenation of null-terminated k=v\0 sequences, with a final
- // \0 to terminate.
- match env {
- Some(env) => {
- let mut blk = Vec::new();
-
- for pair in env.iter() {
- let kv = format!("{}={}",
- pair.ref0().as_str().unwrap(),
- pair.ref1().as_str().unwrap());
- blk.extend(kv.as_slice().utf16_units());
- blk.push(0);
- }
-
- blk.push(0);
-
- cb(blk.as_mut_ptr() as *mut c_void)
- }
- _ => cb(ptr::null_mut())
- }
-}
-
-#[cfg(windows)]
-fn with_dirp<T>(d: Option<&CString>, cb: |*const u16| -> T) -> T {
- match d {
- Some(dir) => {
- let dir_str = dir.as_str()
- .expect("expected workingdirectory to be utf-8 encoded");
- let mut dir_str: Vec<u16> = dir_str.utf16_units().collect();
- dir_str.push(0);
- cb(dir_str.as_ptr())
- },
- None => cb(ptr::null())
- }
-}
-
-#[cfg(windows)]
-fn free_handle(handle: *mut ()) {
- assert!(unsafe {
- libc::CloseHandle(mem::transmute(handle)) != 0
- })
-}
-
-#[cfg(unix)]
-fn free_handle(_handle: *mut ()) {
- // unix has no process handle object, just a pid
-}
-
-#[cfg(unix)]
-fn translate_status(status: c_int) -> rtio::ProcessExit {
- #![allow(non_snake_case)]
- #[cfg(any(target_os = "linux", target_os = "android"))]
- mod imp {
- pub fn WIFEXITED(status: i32) -> bool { (status & 0xff) == 0 }
- pub fn WEXITSTATUS(status: i32) -> i32 { (status >> 8) & 0xff }
- pub fn WTERMSIG(status: i32) -> i32 { status & 0x7f }
- }
-
- #[cfg(any(target_os = "macos",
- target_os = "ios",
- target_os = "freebsd",
- target_os = "dragonfly"))]
- mod imp {
- pub fn WIFEXITED(status: i32) -> bool { (status & 0x7f) == 0 }
- pub fn WEXITSTATUS(status: i32) -> i32 { status >> 8 }
- pub fn WTERMSIG(status: i32) -> i32 { status & 0o177 }
- }
-
- if imp::WIFEXITED(status) {
- rtio::ExitStatus(imp::WEXITSTATUS(status) as int)
- } else {
- rtio::ExitSignal(imp::WTERMSIG(status) as int)
- }
-}
-
-/**
- * Waits for a process to exit and returns the exit code, failing
- * if there is no process with the specified id.
- *
- * Note that this is private to avoid race conditions on unix where if
- * a user calls waitpid(some_process.get_id()) then some_process.finish()
- * and some_process.destroy() and some_process.finalize() will then either
- * operate on a none-existent process or, even worse, on a newer process
- * with the same id.
- */
-#[cfg(windows)]
-fn waitpid(pid: pid_t, deadline: u64) -> IoResult<rtio::ProcessExit> {
- use libc::types::os::arch::extra::DWORD;
- use libc::consts::os::extra::{
- SYNCHRONIZE,
- PROCESS_QUERY_INFORMATION,
- FALSE,
- STILL_ACTIVE,
- INFINITE,
- WAIT_TIMEOUT,
- WAIT_OBJECT_0,
- };
- use libc::funcs::extra::kernel32::{
- OpenProcess,
- GetExitCodeProcess,
- CloseHandle,
- WaitForSingleObject,
- };
-
- unsafe {
- let process = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION,
- FALSE,
- pid as DWORD);
- if process.is_null() {
- return Err(super::last_error())
- }
-
- loop {
- let mut status = 0;
- if GetExitCodeProcess(process, &mut status) == FALSE {
- let err = Err(super::last_error());
- assert!(CloseHandle(process) != 0);
- return err;
- }
- if status != STILL_ACTIVE {
- assert!(CloseHandle(process) != 0);
- return Ok(rtio::ExitStatus(status as int));
- }
- let interval = if deadline == 0 {
- INFINITE
- } else {
- let now = ::io::timer::now();
- if deadline < now {0} else {(deadline - now) as u32}
- };
- match WaitForSingleObject(process, interval) {
- WAIT_OBJECT_0 => {}
- WAIT_TIMEOUT => {
- assert!(CloseHandle(process) != 0);
- return Err(util::timeout("process wait timed out"))
- }
- _ => {
- let err = Err(super::last_error());
- assert!(CloseHandle(process) != 0);
- return err
- }
- }
- }
- }
-}
-
-#[cfg(unix)]
-fn waitpid(pid: pid_t, deadline: u64) -> IoResult<rtio::ProcessExit> {
- use std::cmp;
- use std::comm;
-
- static mut WRITE_FD: libc::c_int = 0;
-
- let mut status = 0 as c_int;
- if deadline == 0 {
- return match retry(|| unsafe { c::waitpid(pid, &mut status, 0) }) {
- -1 => panic!("unknown waitpid error: {}", super::last_error().code),
- _ => Ok(translate_status(status)),
- }
- }
-
- // On unix, wait() and its friends have no timeout parameters, so there is
- // no way to time out a thread in wait(). From some googling and some
- // thinking, it appears that there are a few ways to handle timeouts in
- // wait(), but the only real reasonable one for a multi-threaded program is
- // to listen for SIGCHLD.
- //
- // With this in mind, the waiting mechanism with a timeout barely uses
- // waitpid() at all. There are a few times that waitpid() is invoked with
- // WNOHANG, but otherwise all the necessary blocking is done by waiting for
- // a SIGCHLD to arrive (and that blocking has a timeout). Note, however,
- // that waitpid() is still used to actually reap the child.
- //
- // Signal handling is super tricky in general, and this is no exception. Due
- // to the async nature of SIGCHLD, we use the self-pipe trick to transmit
- // data out of the signal handler to the rest of the application. The first
- // idea would be to have each thread waiting with a timeout to read this
- // output file descriptor, but a write() is akin to a signal(), not a
- // broadcast(), so it would only wake up one thread, and possibly the wrong
- // thread. Hence a helper thread is used.
- //
- // The helper thread here is responsible for farming requests for a
- // waitpid() with a timeout, and then processing all of the wait requests.
- // By guaranteeing that only this helper thread is reading half of the
- // self-pipe, we're sure that we'll never lose a SIGCHLD. This helper thread
- // is also responsible for select() to wait for incoming messages or
- // incoming SIGCHLD messages, along with passing an appropriate timeout to
- // select() to wake things up as necessary.
- //
- // The ordering of the following statements is also very purposeful. First,
- // we must be guaranteed that the helper thread is booted and available to
- // receive SIGCHLD signals, and then we must also ensure that we do a
- // nonblocking waitpid() at least once before we go ask the sigchld helper.
- // This prevents the race where the child exits, we boot the helper, and
- // then we ask for the child's exit status (never seeing a sigchld).
- //
- // The actual communication between the helper thread and this thread is
- // quite simple, just a channel moving data around.
-
- HELPER.boot(register_sigchld, waitpid_helper);
-
- match waitpid_nowait(pid) {
- Some(ret) => return Ok(ret),
- None => {}
- }
-
- let (tx, rx) = channel();
- HELPER.send(NewChild(pid, tx, deadline));
- return match rx.recv_opt() {
- Ok(e) => Ok(e),
- Err(()) => Err(util::timeout("wait timed out")),
- };
-
- // Register a new SIGCHLD handler, returning the reading half of the
- // self-pipe plus the old handler registered (return value of sigaction).
- //
- // Be sure to set up the self-pipe first because as soon as we register a
- // handler we're going to start receiving signals.
- fn register_sigchld() -> (libc::c_int, c::sigaction) {
- unsafe {
- let mut pipes = [0, ..2];
- assert_eq!(libc::pipe(pipes.as_mut_ptr()), 0);
- util::set_nonblocking(pipes[0], true).ok().unwrap();
- util::set_nonblocking(pipes[1], true).ok().unwrap();
- WRITE_FD = pipes[1];
-
- let mut old: c::sigaction = mem::zeroed();
- let mut new: c::sigaction = mem::zeroed();
- new.sa_handler = sigchld_handler;
- new.sa_flags = c::SA_NOCLDSTOP;
- assert_eq!(c::sigaction(c::SIGCHLD, &new, &mut old), 0);
- (pipes[0], old)
- }
- }
-
- // Helper thread for processing SIGCHLD messages
- fn waitpid_helper(input: libc::c_int,
- messages: Receiver<Req>,
- (read_fd, old): (libc::c_int, c::sigaction)) {
- util::set_nonblocking(input, true).ok().unwrap();
- let mut set: c::fd_set = unsafe { mem::zeroed() };
- let mut tv: libc::timeval;
- let mut active = Vec::<(libc::pid_t, Sender<rtio::ProcessExit>, u64)>::new();
- let max = cmp::max(input, read_fd) + 1;
-
- 'outer: loop {
- // Figure out the timeout of our syscall-to-happen. If we're waiting
- // for some processes, then they'll have a timeout, otherwise we
- // wait indefinitely for a message to arrive.
- //
- // FIXME: sure would be nice to not have to scan the entire array
- let min = active.iter().map(|a| *a.ref2()).enumerate().min_by(|p| {
- p.val1()
- });
- let (p, idx) = match min {
- Some((idx, deadline)) => {
- let now = ::io::timer::now();
- let ms = if now < deadline {deadline - now} else {0};
- tv = util::ms_to_timeval(ms);
- (&mut tv as *mut _, idx)
- }
- None => (ptr::null_mut(), -1),
- };
-
- // Wait for something to happen
- c::fd_set(&mut set, input);
- c::fd_set(&mut set, read_fd);
- match unsafe { c::select(max, &mut set, ptr::null_mut(),
- ptr::null_mut(), p) } {
- // interrupted, retry
- -1 if os::errno() == libc::EINTR as int => continue,
-
- // We read something, break out and process
- 1 | 2 => {}
-
- // Timeout, the pending request is removed
- 0 => {
- drop(active.remove(idx));
- continue
- }
-
- n => panic!("error in select {} ({})", os::errno(), n),
- }
-
- // Process any pending messages
- if drain(input) {
- loop {
- match messages.try_recv() {
- Ok(NewChild(pid, tx, deadline)) => {
- active.push((pid, tx, deadline));
- }
- Err(comm::Disconnected) => {
- assert!(active.len() == 0);
- break 'outer;
- }
- Err(comm::Empty) => break,
- }
- }
- }
-
- // If a child exited (somehow received SIGCHLD), then poll all
- // children to see if any of them exited.
- //
- // We also attempt to be responsible netizens when dealing with
- // SIGCHLD by invoking any previous SIGCHLD handler instead of just
- // ignoring any previous SIGCHLD handler. Note that we don't provide
- // a 1:1 mapping of our handler invocations to the previous handler
- // invocations because we drain the `read_fd` entirely. This is
- // probably OK because the kernel is already allowed to coalesce
- // simultaneous signals, we're just doing some extra coalescing.
- //
- // Another point of note is that this likely runs the signal handler
- // on a different thread than the one that received the signal. I
- // *think* this is ok at this time.
- //
- // The main reason for doing this is to allow stdtest to run native
- // tests as well. Both libgreen and libnative are running around
- // with process timeouts, but libgreen should get there first
- // (currently libuv doesn't handle old signal handlers).
- if drain(read_fd) {
- let i: uint = unsafe { mem::transmute(old.sa_handler) };
- if i != 0 {
- assert!(old.sa_flags & c::SA_SIGINFO == 0);
- (old.sa_handler)(c::SIGCHLD);
- }
-
- // FIXME: sure would be nice to not have to scan the entire
- // array...
- active.retain(|&(pid, ref tx, _)| {
- match waitpid_nowait(pid) {
- Some(msg) => { tx.send(msg); false }
- None => true,
- }
- });
- }
- }
-
- // Once this helper thread is done, we re-register the old sigchld
- // handler and close our intermediate file descriptors.
- unsafe {
- assert_eq!(c::sigaction(c::SIGCHLD, &old, ptr::null_mut()), 0);
- let _ = libc::close(read_fd);
- let _ = libc::close(WRITE_FD);
- WRITE_FD = -1;
- }
- }
-
- // Drain all pending data from the file descriptor, returning if any data
- // could be drained. This requires that the file descriptor is in
- // nonblocking mode.
- fn drain(fd: libc::c_int) -> bool {
- let mut ret = false;
- loop {
- let mut buf = [0u8, ..1];
- match unsafe {
- libc::read(fd, buf.as_mut_ptr() as *mut libc::c_void,
- buf.len() as libc::size_t)
- } {
- n if n > 0 => { ret = true; }
- 0 => return true,
- -1 if util::wouldblock() => return ret,
- n => panic!("bad read {} ({})", os::last_os_error(), n),
- }
- }
- }
-
- // Signal handler for SIGCHLD signals, must be async-signal-safe!
- //
- // This function will write to the writing half of the "self pipe" to wake
- // up the helper thread if it's waiting. Note that this write must be
- // nonblocking because if it blocks and the reader is the thread we
- // interrupted, then we'll deadlock.
- //
- // When writing, if the write returns EWOULDBLOCK then we choose to ignore
- // it. At that point we're guaranteed that there's something in the pipe
- // which will wake up the other end at some point, so we just allow this
- // signal to be coalesced with the pending signals on the pipe.
- extern fn sigchld_handler(_signum: libc::c_int) {
- let msg = 1i;
- match unsafe {
- libc::write(WRITE_FD, &msg as *const _ as *const libc::c_void, 1)
- } {
- 1 => {}
- -1 if util::wouldblock() => {} // see above comments
- n => panic!("bad error on write fd: {} {}", n, os::errno()),
- }
- }
-}
-
-fn waitpid_nowait(pid: pid_t) -> Option<rtio::ProcessExit> {
- return waitpid_os(pid);
-
- // This code path isn't necessary on windows
- #[cfg(windows)]
- fn waitpid_os(_pid: pid_t) -> Option<rtio::ProcessExit> { None }
-
- #[cfg(unix)]
- fn waitpid_os(pid: pid_t) -> Option<rtio::ProcessExit> {
- let mut status = 0 as c_int;
- match retry(|| unsafe {
- c::waitpid(pid, &mut status, c::WNOHANG)
- }) {
- n if n == pid => Some(translate_status(status)),
- 0 => None,
- n => panic!("unknown waitpid error `{}`: {}", n,
- super::last_error().code),
- }
- }
-}
-
-#[cfg(test)]
-mod tests {
-
- #[test] #[cfg(windows)]
- fn test_make_command_line() {
- use std::str;
- use std::c_str::CString;
- use super::make_command_line;
-
- fn test_wrapper(prog: &str, args: &[&str]) -> String {
- make_command_line(&prog.to_c_str(),
- args.iter()
- .map(|a| a.to_c_str())
- .collect::<Vec<CString>>()
- .as_slice())
- }
-
- assert_eq!(
- test_wrapper("prog", ["aaa", "bbb", "ccc"]),
- "prog aaa bbb ccc".to_string()
- );
-
- assert_eq!(
- test_wrapper("C:\\Program Files\\blah\\blah.exe", ["aaa"]),
- "\"C:\\Program Files\\blah\\blah.exe\" aaa".to_string()
- );
- assert_eq!(
- test_wrapper("C:\\Program Files\\test", ["aa\"bb"]),
- "\"C:\\Program Files\\test\" aa\\\"bb".to_string()
- );
- assert_eq!(
- test_wrapper("echo", ["a b c"]),
- "echo \"a b c\"".to_string()
- );
- assert_eq!(
- test_wrapper("\u03c0\u042f\u97f3\u00e6\u221e", []),
- "\u03c0\u042f\u97f3\u00e6\u221e".to_string()
- );
- }
-}
projects / rust.git / commitdiff