563 lines
17 KiB
Rust
563 lines
17 KiB
Rust
mod clone3;
|
|
mod io;
|
|
|
|
use {
|
|
crate::{
|
|
async_engine::{AsyncEngine, AsyncFd, SpawnedFuture},
|
|
compositor::{DISPLAY, WAYLAND_DISPLAY},
|
|
event_loop::EventLoop,
|
|
forker::{
|
|
clone3::{fork_with_pidfd, Forked},
|
|
io::{IoIn, IoOut},
|
|
},
|
|
state::State,
|
|
utils::{
|
|
buffd::BufFdError, copyhashmap::CopyHashMap, errorfmt::ErrorFmt, numcell::NumCell,
|
|
queue::AsyncQueue,
|
|
},
|
|
wheel::Wheel,
|
|
xwayland,
|
|
},
|
|
bincode::{
|
|
error::{DecodeError, EncodeError},
|
|
Decode, Encode,
|
|
},
|
|
jay_config::_private::bincode_ops,
|
|
log::Level,
|
|
std::{
|
|
cell::{Cell, RefCell},
|
|
env,
|
|
ffi::OsStr,
|
|
io::{Read, Write},
|
|
os::unix::ffi::OsStrExt,
|
|
rc::{Rc, Weak},
|
|
task::{Poll, Waker},
|
|
},
|
|
thiserror::Error,
|
|
uapi::{c, pipe2, Errno, Fd, IntoUstr, OwnedFd, UstrPtr},
|
|
};
|
|
|
|
pub struct ForkerProxy {
|
|
pidfd: Rc<OwnedFd>,
|
|
pid: c::pid_t,
|
|
socket: Rc<OwnedFd>,
|
|
task_in: Cell<Option<SpawnedFuture<()>>>,
|
|
task_out: Cell<Option<SpawnedFuture<()>>>,
|
|
task_proc: Cell<Option<SpawnedFuture<()>>>,
|
|
outgoing: AsyncQueue<ServerMessage>,
|
|
next_id: NumCell<u32>,
|
|
pending_pidfds: CopyHashMap<u32, Weak<PidfdHandoff>>,
|
|
fds: RefCell<Vec<Rc<OwnedFd>>>,
|
|
}
|
|
|
|
struct PidfdHandoff {
|
|
pidfd: Cell<Option<Result<(OwnedFd, c::pid_t), ForkerError>>>,
|
|
waiter: Cell<Option<Waker>>,
|
|
}
|
|
|
|
#[derive(Debug, Error)]
|
|
pub enum ForkerError {
|
|
#[error("Could not create a socketpair")]
|
|
Socketpair(#[source] crate::utils::oserror::OsError),
|
|
#[error("Could not fork")]
|
|
Fork(#[source] crate::utils::oserror::OsError),
|
|
#[error("Could not read the next message")]
|
|
ReadFailed(#[source] BufFdError),
|
|
#[error("Could not write the next message")]
|
|
WriteFailed(#[source] BufFdError),
|
|
#[error("Could not decode the next message")]
|
|
DecodeFailed(#[source] DecodeError),
|
|
#[error("Could not encode the next message")]
|
|
EncodeFailed(#[source] EncodeError),
|
|
#[error("Could not fork")]
|
|
PidfdForkFailed,
|
|
}
|
|
|
|
impl ForkerProxy {
|
|
pub fn clear(&self) {
|
|
self.task_in.take();
|
|
self.task_out.take();
|
|
self.task_proc.take();
|
|
}
|
|
|
|
pub fn create() -> Result<Self, ForkerError> {
|
|
let (parent, child) = match uapi::socketpair(
|
|
c::AF_UNIX,
|
|
c::SOCK_STREAM | c::SOCK_CLOEXEC | c::SOCK_NONBLOCK,
|
|
0,
|
|
) {
|
|
Ok(o) => o,
|
|
Err(e) => return Err(ForkerError::Socketpair(e.into())),
|
|
};
|
|
let pid = uapi::getpid();
|
|
match fork_with_pidfd(false)? {
|
|
Forked::Parent { pid, pidfd } => Ok(ForkerProxy {
|
|
pidfd: Rc::new(pidfd),
|
|
pid,
|
|
socket: Rc::new(parent),
|
|
task_in: Cell::new(None),
|
|
task_out: Cell::new(None),
|
|
task_proc: Cell::new(None),
|
|
outgoing: Default::default(),
|
|
next_id: Default::default(),
|
|
pending_pidfds: Default::default(),
|
|
fds: Default::default(),
|
|
}),
|
|
Forked::Child { .. } => Forker::handle(pid, child),
|
|
}
|
|
}
|
|
|
|
pub fn install(self: &Rc<Self>, state: &Rc<State>) {
|
|
state.forker.set(Some(self.clone()));
|
|
let socket = state.eng.fd(&self.socket).unwrap();
|
|
self.task_proc.set(Some(
|
|
state.eng.spawn(self.clone().check_process(state.clone())),
|
|
));
|
|
self.task_in
|
|
.set(Some(state.eng.spawn(self.clone().incoming(socket.clone()))));
|
|
self.task_out.set(Some(
|
|
state
|
|
.eng
|
|
.spawn(self.clone().outgoing(state.clone(), socket.clone())),
|
|
));
|
|
}
|
|
|
|
pub fn setenv(&self, key: &[u8], val: &[u8]) {
|
|
self.outgoing.push(ServerMessage::SetEnv {
|
|
var: key.to_vec(),
|
|
val: Some(val.to_vec()),
|
|
})
|
|
}
|
|
|
|
pub fn unsetenv(&self, key: &[u8]) {
|
|
self.outgoing.push(ServerMessage::SetEnv {
|
|
var: key.to_vec(),
|
|
val: None,
|
|
})
|
|
}
|
|
|
|
async fn pidfd(&self, id: u32) -> Result<(OwnedFd, c::pid_t), ForkerError> {
|
|
let handoff = Rc::new(PidfdHandoff {
|
|
pidfd: Cell::new(None),
|
|
waiter: Cell::new(None),
|
|
});
|
|
self.pending_pidfds.set(id, Rc::downgrade(&handoff));
|
|
futures_util::future::poll_fn(|ctx| {
|
|
if let Some(pidfd) = handoff.pidfd.take() {
|
|
Poll::Ready(pidfd)
|
|
} else {
|
|
handoff.waiter.set(Some(ctx.waker().clone()));
|
|
Poll::Pending
|
|
}
|
|
})
|
|
.await
|
|
}
|
|
|
|
pub async fn xwayland(
|
|
&self,
|
|
stderr: Rc<OwnedFd>,
|
|
dfd: Rc<OwnedFd>,
|
|
listenfd: Rc<OwnedFd>,
|
|
wmfd: Rc<OwnedFd>,
|
|
waylandfd: Rc<OwnedFd>,
|
|
) -> Result<(OwnedFd, c::pid_t), ForkerError> {
|
|
self.fds
|
|
.borrow_mut()
|
|
.extend([stderr, dfd, listenfd, wmfd, waylandfd]);
|
|
let id = self.next_id.fetch_add(1);
|
|
self.outgoing.push(ServerMessage::Xwayland { id });
|
|
self.pidfd(id).await
|
|
}
|
|
|
|
pub fn spawn(
|
|
&self,
|
|
prog: String,
|
|
args: Vec<String>,
|
|
env: Vec<(String, String)>,
|
|
stderr: Option<Rc<OwnedFd>>,
|
|
) {
|
|
let have_stderr = stderr.is_some();
|
|
if let Some(stderr) = stderr {
|
|
self.fds.borrow_mut().push(stderr);
|
|
}
|
|
self.outgoing.push(ServerMessage::Spawn {
|
|
prog,
|
|
args,
|
|
env,
|
|
stderr: have_stderr,
|
|
})
|
|
}
|
|
|
|
async fn incoming(self: Rc<Self>, socket: AsyncFd) {
|
|
let mut io = IoIn::new(socket);
|
|
loop {
|
|
let msg = match io.read_msg().await {
|
|
Ok(msg) => msg,
|
|
Err(e) => {
|
|
log::error!("Could not read from the ol' forker: {}", ErrorFmt(e));
|
|
self.task_in.take();
|
|
return;
|
|
}
|
|
};
|
|
self.handle_msg(msg, &mut io);
|
|
}
|
|
}
|
|
|
|
fn handle_msg(&self, msg: ForkerMessage, io: &mut IoIn) {
|
|
match msg {
|
|
ForkerMessage::Log { level, msg } => self.handle_log(level, &msg),
|
|
ForkerMessage::PidFd { id, success, pid } => self.handle_pidfd(id, success, io, pid),
|
|
}
|
|
}
|
|
|
|
fn handle_pidfd(&self, id: u32, success: bool, io: &mut IoIn, pid: c::pid_t) {
|
|
let res = match success {
|
|
true => Ok((io.pop_fd().unwrap(), pid)),
|
|
_ => Err(ForkerError::PidfdForkFailed),
|
|
};
|
|
if let Some(handoff) = self.pending_pidfds.remove(&id) {
|
|
if let Some(handoff) = handoff.upgrade() {
|
|
handoff.pidfd.set(Some(res));
|
|
if let Some(w) = handoff.waiter.take() {
|
|
w.wake();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn handle_log(&self, level: usize, msg: &str) {
|
|
let level = match level {
|
|
1 => Level::Error,
|
|
2 => Level::Warn,
|
|
3 => Level::Info,
|
|
4 => Level::Debug,
|
|
5 => Level::Trace,
|
|
_ => Level::Error,
|
|
};
|
|
log::log!(level, "{}", msg);
|
|
}
|
|
|
|
async fn outgoing(self: Rc<Self>, state: Rc<State>, socket: AsyncFd) {
|
|
let mut io = IoOut::new(socket);
|
|
loop {
|
|
let msg = self.outgoing.pop().await;
|
|
for fd in self.fds.borrow_mut().drain(..) {
|
|
io.push_fd(fd);
|
|
}
|
|
if let Err(e) = io.write_msg(msg).await {
|
|
log::error!("Could not write to the ol' forker: {}", ErrorFmt(e));
|
|
self.clear();
|
|
state.forker.set(None);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
async fn check_process(self: Rc<Self>, state: Rc<State>) {
|
|
let pidfd = state.eng.fd(&self.pidfd).unwrap();
|
|
if let Err(e) = pidfd.readable().await {
|
|
log::error!(
|
|
"Cannot wait for the forker pidfd to become readable: {}",
|
|
ErrorFmt(e)
|
|
);
|
|
} else {
|
|
let _ = uapi::waitpid(self.pid, 0);
|
|
}
|
|
log::error!("The ol' forker died. Cannot spawn further processes.");
|
|
self.clear();
|
|
state.forker.set(None);
|
|
}
|
|
}
|
|
|
|
#[derive(Encode, Decode)]
|
|
enum ServerMessage {
|
|
SetEnv {
|
|
var: Vec<u8>,
|
|
val: Option<Vec<u8>>,
|
|
},
|
|
Spawn {
|
|
prog: String,
|
|
args: Vec<String>,
|
|
env: Vec<(String, String)>,
|
|
stderr: bool,
|
|
},
|
|
Xwayland {
|
|
id: u32,
|
|
},
|
|
}
|
|
|
|
#[derive(Encode, Decode)]
|
|
enum ForkerMessage {
|
|
Log {
|
|
level: usize,
|
|
msg: String,
|
|
},
|
|
PidFd {
|
|
id: u32,
|
|
success: bool,
|
|
pid: c::pid_t,
|
|
},
|
|
}
|
|
|
|
struct Forker {
|
|
socket: AsyncFd,
|
|
ae: Rc<AsyncEngine>,
|
|
fds: RefCell<Vec<Rc<OwnedFd>>>,
|
|
outgoing: AsyncQueue<ForkerMessage>,
|
|
pending_spawns: CopyHashMap<c::pid_t, SpawnedFuture<()>>,
|
|
}
|
|
|
|
impl Forker {
|
|
fn handle(ppid: c::pid_t, socket: OwnedFd) -> ! {
|
|
env::set_var("XDG_SESSION_TYPE", "wayland");
|
|
env::remove_var(DISPLAY);
|
|
env::remove_var(WAYLAND_DISPLAY);
|
|
setup_name("the ol' forker");
|
|
setup_deathsig(ppid);
|
|
reset_signals();
|
|
let socket = Rc::new(setup_fds(socket));
|
|
std::panic::set_hook({
|
|
let socket = socket.raw();
|
|
Box::new(move |pi| {
|
|
let msg = ForkerMessage::Log {
|
|
level: log::Level::Error as _,
|
|
msg: format!("The ol' forker panicked: {}", pi),
|
|
};
|
|
let msg = bincode::encode_to_vec(&msg, bincode_ops()).unwrap();
|
|
let _ = Fd::new(socket).write_all(&msg);
|
|
})
|
|
});
|
|
let el = EventLoop::new().unwrap();
|
|
let wheel = Wheel::install(&el).unwrap();
|
|
let ae = AsyncEngine::install(&el, &wheel).unwrap();
|
|
let forker = Rc::new(Forker {
|
|
socket: ae.fd(&socket).unwrap(),
|
|
ae: ae.clone(),
|
|
fds: RefCell::new(vec![]),
|
|
outgoing: Default::default(),
|
|
pending_spawns: Default::default(),
|
|
});
|
|
let _f1 = ae.spawn(forker.clone().incoming());
|
|
let _f2 = ae.spawn(forker.clone().outgoing());
|
|
let _ = el.run();
|
|
unreachable!();
|
|
}
|
|
|
|
async fn outgoing(self: Rc<Self>) {
|
|
let mut io = IoOut::new(self.socket.clone());
|
|
loop {
|
|
let msg = self.outgoing.pop().await;
|
|
for fd in self.fds.borrow_mut().drain(..) {
|
|
io.push_fd(fd);
|
|
}
|
|
io.write_msg(msg).await.unwrap();
|
|
}
|
|
}
|
|
|
|
async fn incoming(self: Rc<Self>) {
|
|
let mut io = IoIn::new(self.socket.clone());
|
|
loop {
|
|
let msg = io.read_msg().await.unwrap();
|
|
self.handle_msg(msg, &mut io);
|
|
}
|
|
}
|
|
|
|
fn handle_msg(self: &Rc<Self>, msg: ServerMessage, io: &mut IoIn) {
|
|
match msg {
|
|
ServerMessage::SetEnv { var, val } => self.handle_set_env(&var, val),
|
|
ServerMessage::Spawn {
|
|
prog,
|
|
args,
|
|
env,
|
|
stderr,
|
|
} => self.handle_spawn(prog, args, env, stderr, io),
|
|
ServerMessage::Xwayland { id } => self.handle_xwayland(io, id),
|
|
}
|
|
}
|
|
|
|
fn handle_set_env(self: &Rc<Self>, var: &[u8], val: Option<Vec<u8>>) {
|
|
let var = OsStr::from_bytes(var);
|
|
match val {
|
|
Some(val) => env::set_var(var, OsStr::from_bytes(&val)),
|
|
_ => env::remove_var(var),
|
|
}
|
|
}
|
|
|
|
fn handle_xwayland(self: &Rc<Self>, io: &mut IoIn, id: u32) {
|
|
let stderr = io.pop_fd();
|
|
let fds = vec![
|
|
io.pop_fd().unwrap(),
|
|
io.pop_fd().unwrap(),
|
|
io.pop_fd().unwrap(),
|
|
io.pop_fd().unwrap(),
|
|
];
|
|
let (prog, args) = xwayland::build_args(&fds);
|
|
let env = vec![("WAYLAND_SOCKET".to_string(), fds[3].raw().to_string())];
|
|
self.spawn(prog, args, env, stderr, fds, Some(id));
|
|
}
|
|
|
|
fn handle_spawn(
|
|
self: &Rc<Self>,
|
|
prog: String,
|
|
args: Vec<String>,
|
|
env: Vec<(String, String)>,
|
|
stderr: bool,
|
|
io: &mut IoIn,
|
|
) {
|
|
let stderr = match stderr {
|
|
true => io.pop_fd(),
|
|
_ => None,
|
|
};
|
|
self.spawn(prog, args, env, stderr, vec![], None)
|
|
}
|
|
|
|
fn spawn(
|
|
self: &Rc<Self>,
|
|
prog: String,
|
|
args: Vec<String>,
|
|
env: Vec<(String, String)>,
|
|
stderr: Option<OwnedFd>,
|
|
fds: Vec<OwnedFd>,
|
|
pidfd_id: Option<u32>,
|
|
) {
|
|
let (read, mut write) = pipe2(c::O_CLOEXEC).unwrap();
|
|
let res = match fork_with_pidfd(false) {
|
|
Ok(o) => o,
|
|
Err(e) => {
|
|
if let Some(id) = pidfd_id {
|
|
self.outgoing.push(ForkerMessage::PidFd {
|
|
id,
|
|
success: false,
|
|
pid: 0,
|
|
});
|
|
}
|
|
self.outgoing.push(ForkerMessage::Log {
|
|
level: log::Level::Error as usize,
|
|
msg: ErrorFmt(e).to_string(),
|
|
});
|
|
return;
|
|
}
|
|
};
|
|
match res {
|
|
Forked::Parent { pid, pidfd } => {
|
|
if let Some(id) = pidfd_id {
|
|
self.fds.borrow_mut().push(Rc::new(pidfd));
|
|
self.outgoing.push(ForkerMessage::PidFd {
|
|
id,
|
|
success: true,
|
|
pid,
|
|
});
|
|
}
|
|
drop(write);
|
|
let slf = self.clone();
|
|
let spawn = self.ae.spawn(async move {
|
|
let read = slf.ae.fd(&Rc::new(read)).unwrap();
|
|
if let Err(e) = read.readable().await {
|
|
log::error!(
|
|
"Cannot wait for the child fd to become readable: {}",
|
|
ErrorFmt(e)
|
|
);
|
|
} else {
|
|
let mut s = String::new();
|
|
let _ = Fd::new(read.raw()).read_to_string(&mut s);
|
|
if s.len() > 0 {
|
|
slf.outgoing.push(ForkerMessage::Log {
|
|
level: log::Level::Error as _,
|
|
msg: format!("Could not spawn `{}`: {}", prog, s),
|
|
});
|
|
}
|
|
}
|
|
slf.pending_spawns.remove(&pid);
|
|
});
|
|
self.pending_spawns.set(pid, spawn);
|
|
}
|
|
Forked::Child { .. } => {
|
|
let err = (|| {
|
|
if let Some(stderr) = stderr {
|
|
uapi::dup2(stderr.raw(), 2).unwrap();
|
|
}
|
|
for fd in fds {
|
|
let fd = fd.unwrap();
|
|
let res: Result<_, Errno> = (|| {
|
|
uapi::fcntl_setfd(fd, uapi::fcntl_getfd(fd)? & !c::FD_CLOEXEC)?;
|
|
Ok(())
|
|
})();
|
|
if let Err(e) = res {
|
|
return Err(SpawnError::Cloexec(e.into()));
|
|
}
|
|
}
|
|
unsafe {
|
|
c::signal(c::SIGCHLD, c::SIG_DFL);
|
|
}
|
|
for (key, val) in env {
|
|
env::set_var(&key, &val);
|
|
}
|
|
let prog = prog.into_ustr();
|
|
let mut argsnt = UstrPtr::new();
|
|
argsnt.push(&prog);
|
|
for arg in args {
|
|
argsnt.push(arg);
|
|
}
|
|
if let Err(e) = uapi::execvp(&prog, &argsnt) {
|
|
return Err(SpawnError::Exec(e.into()));
|
|
}
|
|
Ok(())
|
|
})();
|
|
if let Err(e) = err {
|
|
let _ = write.write_all(ErrorFmt(e).to_string().as_bytes());
|
|
}
|
|
std::process::exit(1);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, Error)]
|
|
enum SpawnError {
|
|
#[error("exec failed")]
|
|
Exec(#[source] crate::utils::oserror::OsError),
|
|
#[error("Could not unset cloexec flag")]
|
|
Cloexec(#[source] crate::utils::oserror::OsError),
|
|
}
|
|
|
|
fn setup_fds(mut socket: OwnedFd) -> OwnedFd {
|
|
if socket.raw() != 0 {
|
|
uapi::dup3(socket.unwrap(), 0, 0).unwrap();
|
|
socket = OwnedFd::new(0);
|
|
}
|
|
uapi::close_range(1, c::c_uint::MAX, 0).unwrap();
|
|
uapi::dup3(socket.raw(), 3, c::O_CLOEXEC).unwrap();
|
|
socket = OwnedFd::new(3);
|
|
let fd = uapi::open("/dev/null", c::O_RDWR, 0).unwrap().unwrap();
|
|
assert!(fd == 0);
|
|
uapi::dup2(0, 1).unwrap();
|
|
uapi::dup2(0, 2).unwrap();
|
|
socket
|
|
}
|
|
|
|
fn reset_signals() {
|
|
const NSIG: c::c_int = 64;
|
|
unsafe {
|
|
for sig in 1..=NSIG {
|
|
c::signal(sig, c::SIG_DFL);
|
|
}
|
|
c::signal(c::SIGCHLD, c::SIG_IGN);
|
|
}
|
|
}
|
|
|
|
fn setup_deathsig(ppid: c::pid_t) {
|
|
unsafe {
|
|
let res = c::prctl(c::PR_SET_PDEATHSIG, c::SIGKILL as c::c_ulong);
|
|
uapi::map_err!(res).unwrap();
|
|
if ppid != uapi::getppid() {
|
|
std::process::exit(0);
|
|
}
|
|
}
|
|
}
|
|
|
|
fn setup_name(name: &str) {
|
|
unsafe {
|
|
let name = name.into_ustr();
|
|
c::prctl(c::PR_SET_NAME, name.as_ptr());
|
|
}
|
|
}
|