use crate::{
buffer::Buffer,
channels::Channels,
connection_status::ConnectionState,
frames::Frames,
heartbeat::Heartbeat,
internal_rpc::InternalRPC,
reactor::{ReactorBuilder, ReactorHandle},
socket_state::SocketState,
tcp::{HandshakeResult, MidHandshakeTlsStream, TcpStream},
thread::ThreadHandle,
Configuration, ConnectionStatus, Error, PromiseResolver, Result,
};
use amq_protocol::frame::{gen_frame, parse_frame, AMQPFrame, GenError};
use log::{error, trace};
use std::{
collections::VecDeque,
io::{self, Write},
sync::Arc,
thread::Builder as ThreadBuilder,
time::Duration,
};
const FRAMES_STORAGE: usize = 32;
#[derive(Debug, PartialEq)]
enum Status {
Initial,
Setup,
Stop,
}
pub struct IoLoop {
connection_status: ConnectionStatus,
configuration: Configuration,
channels: Channels,
internal_rpc: InternalRPC,
frames: Frames,
heartbeat: Heartbeat,
socket_state: SocketState,
reactor: Box<dyn ReactorHandle + Send>,
reactor_thread_handle: ThreadHandle,
connection_io_loop_handle: ThreadHandle,
handshake: Option<MidHandshakeTlsStream>,
stream: Option<TcpStream>,
status: Status,
frame_size: usize,
receive_buffer: Buffer,
send_buffer: Buffer,
serialized_frames: VecDeque<(u64, Option<PromiseResolver<()>>)>,
}
impl IoLoop {
#[allow(clippy::too_many_arguments)]
pub(crate) fn new(
connection_status: ConnectionStatus,
configuration: Configuration,
channels: Channels,
internal_rpc: InternalRPC,
frames: Frames,
socket_state: SocketState,
connection_io_loop_handle: ThreadHandle,
stream: HandshakeResult,
reactor_builder: &dyn ReactorBuilder,
) -> Result<Self> {
let heartbeat = Heartbeat::new(channels.clone());
let mut reactor = reactor_builder.build(heartbeat.clone())?;
let reactor_handle = reactor.handle();
let frame_size = std::cmp::max(8192, configuration.frame_max() as usize);
let (mut stream, mut handshake) = match stream {
Ok(stream) => (Some(stream), None),
Err(error) => (None, Some(error.into_mid_handshake_tls_stream()?)),
};
let source = stream
.as_deref_mut()
.unwrap_or_else(|| handshake.as_mut().unwrap().get_mut());
reactor.register(source, socket_state.handle())?;
let reactor_thread_handle = reactor.start()?;
Ok(Self {
connection_status,
configuration,
channels,
internal_rpc,
frames,
heartbeat,
socket_state,
reactor: reactor_handle,
reactor_thread_handle,
connection_io_loop_handle,
stream,
handshake,
status: Status::Initial,
frame_size,
receive_buffer: Buffer::with_capacity(FRAMES_STORAGE * frame_size),
send_buffer: Buffer::with_capacity(FRAMES_STORAGE * frame_size),
serialized_frames: VecDeque::default(),
})
}
fn ensure_setup(&mut self) {
if self.status != Status::Setup && self.connection_status.connected() {
let frame_max = self.configuration.frame_max() as usize;
self.frame_size = std::cmp::max(self.frame_size, frame_max);
self.receive_buffer.grow(FRAMES_STORAGE * self.frame_size);
self.send_buffer.grow(FRAMES_STORAGE * self.frame_size);
let heartbeat = self.configuration.heartbeat();
if heartbeat != 0 {
let heartbeat = Duration::from_millis(u64::from(heartbeat) * 500); self.heartbeat.set_timeout(heartbeat);
}
self.status = Status::Setup;
}
}
fn has_data(&self) -> bool {
self.frames.has_pending()
|| self.send_buffer.available_data() > 0
|| !self.serialized_frames.is_empty()
}
fn can_write(&mut self) -> bool {
self.socket_state.writable() && self.has_data() && !self.connection_status.blocked()
}
fn can_read(&mut self) -> bool {
self.socket_state.readable()
}
fn can_parse(&self) -> bool {
self.receive_buffer.available_data() > 0
}
fn should_continue(&self) -> bool {
(self.status == Status::Initial
|| self.connection_status.connected()
|| self.connection_status.closing())
&& self.status != Status::Stop
&& !self.connection_status.errored()
}
pub fn start(mut self) -> Result<()> {
let waker = self.socket_state.handle();
self.connection_io_loop_handle.clone().register(
ThreadBuilder::new()
.name("io_loop".to_owned())
.spawn(move || {
while self.should_continue() {
if let Err(err) = self.run() {
self.critical_error(err)?;
}
}
self.reactor.shutdown();
self.reactor_thread_handle.wait("reactor")
})?,
);
waker.wake();
Ok(())
}
fn poll_internal_rpc(&self) -> Result<()> {
self.internal_rpc.poll(&self.channels)
}
fn poll_socket_events(&mut self) -> Result<()> {
self.socket_state.poll_events();
if self.socket_state.error() {
self.critical_error(io::Error::from(io::ErrorKind::ConnectionAborted).into())?;
}
if self.socket_state.closed() {
self.critical_error(io::Error::from(io::ErrorKind::ConnectionReset).into())?;
}
self.poll_internal_rpc()
}
fn run(&mut self) -> Result<()> {
trace!("io_loop run");
self.ensure_setup();
self.poll_socket_events()?;
trace!(
"io_loop do_run; can_read={}, can_write={}, has_data={}",
self.socket_state.readable(),
self.socket_state.writable(),
self.has_data()
);
if !self.can_read() && !self.can_write() {
self.socket_state.wait();
}
self.poll_socket_events()?;
if let Some(handshake) = self.handshake.take() {
match handshake.handshake() {
Ok(stream) => self.stream = Some(stream),
Err(error) => self.handshake = Some(error.into_mid_handshake_tls_stream()?),
}
if self.handshake.is_some() {
return Ok(());
}
}
self.write()?;
if self.connection_status.closed() {
self.status = Status::Stop;
}
if self.should_continue() {
self.read()?;
}
self.handle_frames()?;
trace!(
"io_loop do_run done; can_read={}, can_write={}, has_data={}, status={:?}",
self.socket_state.readable(),
self.socket_state.writable(),
self.has_data(),
self.status
);
self.poll_internal_rpc()
}
fn critical_error(&mut self, error: Error) -> Result<()> {
if let Some(resolver) = self.connection_status.connection_resolver() {
resolver.swear(Err(error.clone()));
}
self.status = Status::Stop;
self.reactor.shutdown();
self.channels.set_connection_error(error.clone())?;
for (_, resolver) in std::mem::take(&mut self.serialized_frames) {
if let Some(resolver) = resolver {
resolver.swear(Err(error.clone()));
}
}
Err(error)
}
fn handle_write_result(&mut self, result: Result<()>) -> Result<()> {
if let Err(e) = self.socket_state.handle_write_result(result) {
error!("error writing: {:?}", e);
self.critical_error(e)?;
}
self.poll_internal_rpc()
}
fn flush(&mut self) -> Result<()> {
self.stream.as_mut().unwrap().flush()?;
self.poll_internal_rpc()
}
fn write(&mut self) -> Result<()> {
if self.socket_state.writable() {
let res = self.flush();
self.handle_write_result(res)?;
}
while self.can_write() {
let res = self.write_to_stream();
self.handle_write_result(res)?;
}
self.poll_internal_rpc()
}
fn read(&mut self) -> Result<()> {
while self.can_read() {
let res = self.read_from_stream();
if let Err(e) = self.socket_state.handle_read_result(res) {
error!("error reading: {:?}", e);
self.critical_error(e)?;
}
}
self.poll_internal_rpc()
}
fn write_to_stream(&mut self) -> Result<()> {
self.flush()?;
self.serialize()?;
let sz = self.send_buffer.write_to(self.stream.as_mut().unwrap())?;
if sz > 0 {
self.heartbeat.update_last_write();
trace!("wrote {} bytes", sz);
self.send_buffer.consume(sz);
let mut written = sz as u64;
while written > 0 {
if let Some((to_write, resolver)) = self.serialized_frames.pop_front() {
if written < to_write {
self.serialized_frames
.push_front((to_write - written, resolver));
trace!("{} to write to complete this frame", to_write - written);
written = 0;
} else {
if let Some(resolver) = resolver {
resolver.swear(Ok(()));
}
written -= to_write;
}
} else {
error!(
"We've written {} but didn't expect to write anything",
written
);
break;
}
}
if self.send_buffer.available_data() > 0 {
trace!("Still {} to write", self.send_buffer.available_data());
}
self.flush()?;
} else {
error!("Socket was writable but we wrote 0, marking as wouldblock");
self.socket_state
.handle_write_result(Err(io::Error::from(io::ErrorKind::WouldBlock).into()))?;
}
self.poll_internal_rpc()
}
fn read_from_stream(&mut self) -> Result<()> {
match self.connection_status.state() {
ConnectionState::Closed => Ok(()),
ConnectionState::Error => Err(Error::InvalidConnectionState(ConnectionState::Error)),
_ => {
self.receive_buffer
.read_from(self.stream.as_mut().unwrap())
.map(|sz| {
trace!("read {} bytes", sz);
self.receive_buffer.fill(sz);
})?;
self.poll_internal_rpc()
}
}
}
fn serialize(&mut self) -> Result<()> {
while let Some((next_msg, resolver)) = self.frames.pop(self.channels.flow()) {
trace!("will write to buffer: {}", next_msg);
let checkpoint = self.send_buffer.checkpoint();
let res = gen_frame(&next_msg)((&mut self.send_buffer).into());
match res.map(|w| w.into_inner().1) {
Ok(sz) => self.serialized_frames.push_back((sz, resolver)),
Err(e) => {
self.send_buffer.rollback(checkpoint);
match e {
GenError::BufferTooSmall(_) => {
self.frames.retry((next_msg, resolver));
break;
}
e => {
error!("error generating frame: {:?}", e);
self.critical_error(Error::SerialisationError(Arc::new(e)))?;
}
}
}
}
}
self.poll_internal_rpc()
}
fn handle_frames(&mut self) -> Result<()> {
while self.can_parse() {
if let Some(frame) = self.parse()? {
self.channels.handle_frame(frame)?;
} else {
break;
}
}
self.poll_internal_rpc()
}
fn parse(&mut self) -> Result<Option<AMQPFrame>> {
match parse_frame(self.receive_buffer.parsing_context()) {
Ok((i, f)) => {
let consumed = self.receive_buffer.offset(i);
self.receive_buffer.consume(consumed);
Ok(Some(f))
}
Err(e) => {
if !e.is_incomplete() {
error!("parse error: {:?}", e);
self.critical_error(Error::ParsingError(e))?;
}
Ok(None)
}
}
}
}