Files
NotesAgentic/frontend/src-tauri/src/extension_io.rs
T

410 lines
15 KiB
Rust

//! Bounded IO for Host-created anonymous pipes. Never run shutdown on the UI
//! thread: cancellation waits for the native pipe operations to acknowledge it.
use crate::{
extension_job::Job,
extension_stdio::{write_frame, Frames, HostIo, MAX_FRAME_BYTES},
workspace::{HostError, Result},
};
use std::{
io::{BufReader, Read},
os::windows::io::AsRawHandle,
sync::{
atomic::{AtomicBool, Ordering},
mpsc::{self, Receiver, RecvTimeoutError, SyncSender},
Arc, Mutex,
},
thread::JoinHandle,
time::{Duration, Instant},
};
use windows_sys::Win32::System::IO::CancelSynchronousIo;
const QUEUED_FRAMES: usize = 4;
const STDERR_BYTES: usize = 1024 * 1024;
const OUTPUT_BYTES_PER_SECOND: usize = 8 * 1024 * 1024;
const OUTPUT_FRAMES_PER_SECOND: usize = 128;
#[derive(Debug)]
pub enum Event {
Frame(Vec<u8>),
Closed,
}
struct State {
stopped: AtomicBool,
#[cfg(test)]
writing: AtomicBool,
error: Mutex<Option<String>>,
job: Job,
}
impl State {
fn fail(&self, error: &str) {
let mut saved = self.error.lock().unwrap_or_else(|e| e.into_inner());
if saved.is_none() {
*saved = Some(error.to_owned());
}
self.stopped.store(true, Ordering::Release);
let _ = self.job.terminate();
}
fn check(&self) -> Result<()> {
if let Some(error) = &*self.error.lock().unwrap_or_else(|e| e.into_inner()) {
return Err(HostError::new(error));
}
if self.stopped.load(Ordering::Acquire) {
return Err(HostError::new("EXTENSION_IO_CLOSED"));
}
Ok(())
}
}
struct Worker {
state: Arc<State>,
thread: Option<JoinHandle<()>>,
}
impl Worker {
fn spawn(
state: &Arc<State>,
name: &str,
task: impl FnOnce(&State) -> Result<()> + Send + 'static,
) -> Result<Self> {
let local = Arc::clone(state);
let thread = std::thread::Builder::new()
.name(name.into())
.spawn(move || {
match std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| task(&local))) {
Ok(Err(error)) if !local.stopped.load(Ordering::Acquire) => {
local.fail(&error.code)
}
Err(_) => local.fail("EXTENSION_IO_WORKER_FAILED"),
_ => {}
}
})
.map_err(|_| HostError::new("EXTENSION_IO_UNAVAILABLE"))?;
Ok(Self {
state: Arc::clone(state),
thread: Some(thread),
})
}
}
impl Drop for Worker {
fn drop(&mut self) {
self.state.stopped.store(true, Ordering::Release);
if let Some(thread) = self.thread.take() {
// Cancellation is not sticky: retry to cover the interval between
// the worker checking stopped and actually entering Read/WriteFile.
// These workers only issue anonymous-pipe IO, never arbitrary device IO.
while !thread.is_finished() {
unsafe {
CancelSynchronousIo(thread.as_raw_handle());
}
std::thread::sleep(Duration::from_millis(2));
}
let _ = thread.join();
}
}
}
pub struct Pump {
state: Arc<State>,
input: Option<SyncSender<Vec<u8>>>,
output: Receiver<Event>,
workers: Vec<Worker>,
}
impl Pump {
pub(crate) fn start(io: HostIo, job: Job) -> Result<Self> {
let state = Arc::new(State {
stopped: AtomicBool::new(false),
#[cfg(test)]
writing: AtomicBool::new(false),
error: Mutex::new(None),
job,
});
let (input, writes) = mpsc::sync_channel::<Vec<u8>>(1);
let (events, output) = mpsc::sync_channel(QUEUED_FRAMES);
let mut pump = Self {
state,
input: Some(input),
output,
workers: Vec::with_capacity(3),
};
let HostIo {
mut input,
output,
mut error,
} = io;
pump.workers.push(Worker::spawn(
&pump.state,
"extension-stdin",
move |state| {
while !state.stopped.load(Ordering::Acquire) {
match writes.recv_timeout(Duration::from_millis(20)) {
Ok(frame) => {
state.check()?;
#[cfg(test)]
state.writing.store(true, Ordering::Release);
write_frame(&mut input, &frame)?;
#[cfg(test)]
state.writing.store(false, Ordering::Release);
}
Err(RecvTimeoutError::Timeout) => {}
Err(RecvTimeoutError::Disconnected) => return Ok(()),
}
}
Ok(())
},
)?);
pump.workers.push(Worker::spawn(
&pump.state,
"extension-stdout",
move |state| {
let mut frames = Frames::new(BufReader::new(output));
let mut window = Instant::now();
let mut bytes = 0;
let mut count = 0;
while !state.stopped.load(Ordering::Acquire) {
let frame = frames.read()?;
state.check()?;
if window.elapsed() >= Duration::from_secs(1) {
window = Instant::now();
bytes = 0;
count = 0;
}
if let Some(frame) = frame {
bytes += frame.len();
count += 1;
if bytes > OUTPUT_BYTES_PER_SECOND || count > OUTPUT_FRAMES_PER_SECOND {
return Err(HostError::new("EXTENSION_IO_RATE_LIMITED"));
}
events
.try_send(Event::Frame(frame))
.map_err(|_| HostError::new("EXTENSION_IO_OUTPUT_BACKPRESSURE"))?;
} else {
events
.try_send(Event::Closed)
.map_err(|_| HostError::new("EXTENSION_IO_OUTPUT_BACKPRESSURE"))?;
return Ok(());
}
}
Ok(())
},
)?);
pump.workers.push(Worker::spawn(
&pump.state,
"extension-stderr",
move |state| {
// Drain without persisting possible secrets. Diagnostic retention
// needs an explicit redaction policy before it can be enabled.
let mut buffer = [0; 4096];
let mut total = 0;
while !state.stopped.load(Ordering::Acquire) {
let count = error
.read(&mut buffer)
.map_err(|_| HostError::new("EXTENSION_PIPE_READ_FAILED"))?;
if count == 0 {
return Ok(());
}
total += count;
if total > STDERR_BYTES {
return Err(HostError::new("EXTENSION_STDERR_LIMIT_EXCEEDED"));
}
}
Ok(())
},
)?);
Ok(pump)
}
/// Nonblocking admission; at most one pending write plus one in progress.
pub fn send(&self, frame: Vec<u8>) -> Result<()> {
self.send_wait(frame, Duration::ZERO)
}
/// Bounded admission for serial protocol notifications immediately followed
/// by a request; retries retain the same frame, without allocating copies.
pub(crate) fn send_wait(&self, mut frame: Vec<u8>, timeout: Duration) -> Result<()> {
self.state.check()?;
if timeout > Duration::from_secs(1) {
return Err(HostError::new("EXTENSION_IO_TIMEOUT_INVALID"));
}
if frame.is_empty()
|| frame.len() > MAX_FRAME_BYTES
|| frame.contains(&b'\n')
|| frame.contains(&b'\r')
{
return Err(HostError::new("EXTENSION_PIPE_INVALID_FRAME"));
}
let sender = self
.input
.as_ref()
.ok_or_else(|| HostError::new("EXTENSION_IO_INPUT_CLOSED"))?;
let started = Instant::now();
loop {
self.state.check()?;
match sender.try_send(frame) {
Ok(()) => return Ok(()),
Err(mpsc::TrySendError::Disconnected(_)) => {
return Err(HostError::new("EXTENSION_IO_INPUT_CLOSED"))
}
Err(mpsc::TrySendError::Full(value)) => frame = value,
}
if started.elapsed() >= timeout {
return Err(HostError::new("EXTENSION_IO_INPUT_BACKPRESSURE"));
}
std::thread::sleep(Duration::from_millis(1));
}
}
pub fn close_input(&mut self) {
self.input.take();
}
pub fn receive(&self, timeout: Duration) -> Result<Event> {
self.state.check()?;
if timeout > Duration::from_secs(60) {
return Err(HostError::new("EXTENSION_IO_TIMEOUT_INVALID"));
}
let started = Instant::now();
loop {
let remaining = timeout.saturating_sub(started.elapsed());
let result = self
.output
.recv_timeout(remaining.min(Duration::from_millis(20)));
self.state.check()?;
match result {
Ok(event) => return Ok(event),
Err(RecvTimeoutError::Disconnected) => {
return Err(HostError::new("EXTENSION_IO_CLOSED"))
}
Err(RecvTimeoutError::Timeout) if started.elapsed() >= timeout => {
return Err(HostError::new("EXTENSION_IO_TIMEOUT"))
}
Err(RecvTimeoutError::Timeout) => {}
}
}
}
pub fn check(&self) -> Result<()> {
self.state.check()
}
/// Stop the process group first, then cancel and join every pipe worker.
pub fn shutdown(mut self) -> Result<()> {
let result = self.state.job.terminate();
self.state.stopped.store(true, Ordering::Release);
self.input.take();
self.workers.clear();
result
}
}
impl Drop for Pump {
fn drop(&mut self) {
self.state.stopped.store(true, Ordering::Release);
let _ = self.state.job.terminate();
self.input.take();
self.workers.clear();
}
}
#[cfg(test)]
mod tests {
use super::*;
use std::{fs::File, io::Write, os::windows::io::FromRawHandle};
fn pipes() -> (HostIo, [File; 3]) {
fn pair() -> (File, File) {
let mut read = std::ptr::null_mut();
let mut write = std::ptr::null_mut();
assert_ne!(
unsafe {
windows_sys::Win32::System::Pipes::CreatePipe(
&mut read,
&mut write,
std::ptr::null(),
4096,
)
},
0
);
unsafe { (File::from_raw_handle(read), File::from_raw_handle(write)) }
}
let (child_input, input) = pair();
let (output, child_output) = pair();
let (error, child_error) = pair();
(
HostIo {
input,
output,
error,
},
[child_input, child_output, child_error],
)
}
#[test]
fn cancellation_joins_blocked_pipe_workers_even_when_peers_stay_open() {
for _ in 0..20 {
let (io, peers) = pipes();
let pump = Pump::start(io, Job::new().unwrap()).unwrap();
pump.send(vec![b'x'; MAX_FRAME_BYTES]).unwrap();
let started = Instant::now();
loop {
let pending = pump.workers.iter().all(|worker| {
let mut pending = 0;
assert_ne!(
unsafe {
windows_sys::Win32::System::Threading::GetThreadIOPendingFlag(
worker.thread.as_ref().unwrap().as_raw_handle(),
&mut pending,
)
},
0
);
pending != 0
});
if pending && pump.state.writing.load(Ordering::Acquire) {
break;
}
assert!(
started.elapsed() < Duration::from_secs(5),
"workers did not enter native IO"
);
std::thread::sleep(Duration::from_millis(2));
}
pump.send(b"{}".to_vec()).unwrap();
assert_eq!(
pump.send(b"{}".to_vec()).unwrap_err().code,
"EXTENSION_IO_INPUT_BACKPRESSURE"
);
let started = Instant::now();
pump.shutdown().unwrap();
assert!(started.elapsed() < Duration::from_secs(2));
// The peer handles remained open throughout shutdown. No process
// exit or peer EOF is available to mask broken IO cancellation.
drop(peers);
}
}
#[test]
fn output_overflow_and_stderr_flood_fail_without_waiting_for_receive_timeout() {
for stderr in [false, true] {
let (io, [input, mut output, mut error]) = pipes();
let pump = Pump::start(io, Job::new().unwrap()).unwrap();
let sender = std::thread::spawn(move || {
if stderr {
let _ = error.write_all(&vec![b'x'; STDERR_BYTES + 8192]);
} else {
output
.write_all(&b"{}\n".repeat(QUEUED_FRAMES + 2))
.unwrap();
}
(input, output, error)
});
let start = Instant::now();
while pump.check().is_ok() {
assert!(start.elapsed() < Duration::from_secs(5));
std::thread::sleep(Duration::from_millis(2));
}
let expected = if stderr {
"EXTENSION_STDERR_LIMIT_EXCEEDED"
} else {
"EXTENSION_IO_OUTPUT_BACKPRESSURE"
};
assert_eq!(pump.check().unwrap_err().code, expected);
let start = Instant::now();
assert_eq!(
pump.receive(Duration::from_secs(60)).unwrap_err().code,
expected
);
assert!(start.elapsed() < Duration::from_secs(1));
pump.shutdown().unwrap();
drop(sender.join().unwrap());
}
}
}