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#[cfg(test)]
mod data_channel_test;
pub mod data_channel_init;
pub mod data_channel_message;
pub mod data_channel_parameters;
pub mod data_channel_state;
use data_channel_message::*;
use data_channel_parameters::*;
use arc_swap::ArcSwapOption;
use bytes::Bytes;
use std::{
future::Future,
pin::Pin,
sync::{
atomic::{AtomicBool, AtomicU16, AtomicU8, AtomicUsize, Ordering},
Arc, Weak,
},
time::SystemTime,
};
use data::message::message_channel_open::ChannelType;
use sctp::stream::OnBufferedAmountLowFn;
use tokio::sync::{Mutex, Notify};
use util::sync::Mutex as SyncMutex;
use data_channel_state::RTCDataChannelState;
use crate::api::setting_engine::SettingEngine;
use crate::error::{Error, OnErrorHdlrFn, Result};
use crate::sctp_transport::RTCSctpTransport;
use crate::stats::stats_collector::StatsCollector;
use crate::stats::{DataChannelStats, StatsReportType};
const DATA_CHANNEL_BUFFER_SIZE: u16 = u16::MAX;
pub type OnMessageHdlrFn = Box<
dyn (FnMut(DataChannelMessage) -> Pin<Box<dyn Future<Output = ()> + Send + 'static>>)
+ Send
+ Sync,
>;
pub type OnOpenHdlrFn =
Box<dyn (FnOnce() -> Pin<Box<dyn Future<Output = ()> + Send + 'static>>) + Send + Sync>;
pub type OnCloseHdlrFn =
Box<dyn (FnMut() -> Pin<Box<dyn Future<Output = ()> + Send + 'static>>) + Send + Sync>;
#[derive(Default)]
pub struct RTCDataChannel {
pub(crate) stats_id: String,
pub(crate) label: String,
pub(crate) ordered: bool,
pub(crate) max_packet_lifetime: u16,
pub(crate) max_retransmits: u16,
pub(crate) protocol: String,
pub(crate) negotiated: bool,
pub(crate) id: AtomicU16,
pub(crate) ready_state: Arc<AtomicU8>, pub(crate) buffered_amount_low_threshold: AtomicUsize,
pub(crate) detach_called: Arc<AtomicBool>,
pub(crate) on_message_handler: Arc<ArcSwapOption<Mutex<OnMessageHdlrFn>>>,
pub(crate) on_open_handler: SyncMutex<Option<OnOpenHdlrFn>>,
pub(crate) on_close_handler: Arc<ArcSwapOption<Mutex<OnCloseHdlrFn>>>,
pub(crate) on_error_handler: Arc<ArcSwapOption<Mutex<OnErrorHdlrFn>>>,
pub(crate) on_buffered_amount_low: Mutex<Option<OnBufferedAmountLowFn>>,
pub(crate) sctp_transport: Mutex<Option<Weak<RTCSctpTransport>>>,
pub(crate) data_channel: Mutex<Option<Arc<data::data_channel::DataChannel>>>,
pub(crate) notify_tx: Arc<Notify>,
pub(crate) setting_engine: Arc<SettingEngine>,
}
impl RTCDataChannel {
pub(crate) fn new(params: DataChannelParameters, setting_engine: Arc<SettingEngine>) -> Self {
let id = params.negotiated.unwrap_or(0);
RTCDataChannel {
stats_id: format!(
"DataChannel-{}",
SystemTime::now()
.duration_since(SystemTime::UNIX_EPOCH)
.map_or(0, |d| d.as_nanos())
),
label: params.label,
protocol: params.protocol,
negotiated: params.negotiated.is_some(),
id: AtomicU16::new(id),
ordered: params.ordered,
max_packet_lifetime: params.max_packet_life_time,
max_retransmits: params.max_retransmits,
ready_state: Arc::new(AtomicU8::new(RTCDataChannelState::Connecting as u8)),
detach_called: Arc::new(AtomicBool::new(false)),
notify_tx: Arc::new(Notify::new()),
setting_engine,
..Default::default()
}
}
pub(crate) async fn open(&self, sctp_transport: Arc<RTCSctpTransport>) -> Result<()> {
if let Some(association) = sctp_transport.association().await {
{
let mut st = self.sctp_transport.lock().await;
if st.is_none() {
*st = Some(Arc::downgrade(&sctp_transport));
} else {
return Ok(());
}
}
let channel_type;
let reliability_parameter;
if self.max_packet_lifetime == 0 && self.max_retransmits == 0 {
reliability_parameter = 0u32;
if self.ordered {
channel_type = ChannelType::Reliable;
} else {
channel_type = ChannelType::ReliableUnordered;
}
} else if self.max_retransmits != 0 {
reliability_parameter = self.max_retransmits as u32;
if self.ordered {
channel_type = ChannelType::PartialReliableRexmit;
} else {
channel_type = ChannelType::PartialReliableRexmitUnordered;
}
} else {
reliability_parameter = self.max_packet_lifetime as u32;
if self.ordered {
channel_type = ChannelType::PartialReliableTimed;
} else {
channel_type = ChannelType::PartialReliableTimedUnordered;
}
}
let cfg = data::data_channel::Config {
channel_type,
priority: data::message::message_channel_open::CHANNEL_PRIORITY_NORMAL,
reliability_parameter,
label: self.label.clone(),
protocol: self.protocol.clone(),
negotiated: self.negotiated,
};
if !self.negotiated {
self.id.store(
sctp_transport
.generate_and_set_data_channel_id(
sctp_transport.dtls_transport.role().await,
)
.await?,
Ordering::SeqCst,
);
}
let dc = data::data_channel::DataChannel::dial(&association, self.id(), cfg).await?;
dc.set_buffered_amount_low_threshold(
self.buffered_amount_low_threshold.load(Ordering::SeqCst),
);
{
let mut on_buffered_amount_low = self.on_buffered_amount_low.lock().await;
if let Some(f) = on_buffered_amount_low.take() {
dc.on_buffered_amount_low(f);
}
}
self.handle_open(Arc::new(dc)).await;
Ok(())
} else {
Err(Error::ErrSCTPNotEstablished)
}
}
pub async fn transport(&self) -> Option<Weak<RTCSctpTransport>> {
let sctp_transport = self.sctp_transport.lock().await;
sctp_transport.clone()
}
pub fn on_open(&self, f: OnOpenHdlrFn) {
let _ = self.on_open_handler.lock().replace(f);
if self.ready_state() == RTCDataChannelState::Open {
self.do_open();
}
}
fn do_open(&self) {
let on_open_handler = self.on_open_handler.lock().take();
if on_open_handler.is_none() {
return;
}
let detach_data_channels = self.setting_engine.detach.data_channels;
let detach_called = Arc::clone(&self.detach_called);
tokio::spawn(async move {
if let Some(f) = on_open_handler {
f().await;
if detach_data_channels && !detach_called.load(Ordering::SeqCst) {
log::warn!(
"webrtc.DetachDataChannels() enabled but didn't Detach, call Detach from OnOpen"
);
}
}
});
}
pub fn on_close(&self, f: OnCloseHdlrFn) {
self.on_close_handler.store(Some(Arc::new(Mutex::new(f))));
}
pub fn on_message(&self, f: OnMessageHdlrFn) {
self.on_message_handler.store(Some(Arc::new(Mutex::new(f))));
}
async fn do_message(&self, msg: DataChannelMessage) {
if let Some(handler) = &*self.on_message_handler.load() {
let mut f = handler.lock().await;
f(msg).await;
}
}
pub(crate) async fn handle_open(&self, dc: Arc<data::data_channel::DataChannel>) {
{
let mut data_channel = self.data_channel.lock().await;
*data_channel = Some(Arc::clone(&dc));
}
self.set_ready_state(RTCDataChannelState::Open);
self.do_open();
if !self.setting_engine.detach.data_channels {
let ready_state = Arc::clone(&self.ready_state);
let on_message_handler = Arc::clone(&self.on_message_handler);
let on_close_handler = Arc::clone(&self.on_close_handler);
let on_error_handler = Arc::clone(&self.on_error_handler);
let notify_rx = self.notify_tx.clone();
tokio::spawn(async move {
RTCDataChannel::read_loop(
notify_rx,
dc,
ready_state,
on_message_handler,
on_close_handler,
on_error_handler,
)
.await;
});
}
}
pub fn on_error(&self, f: OnErrorHdlrFn) {
self.on_error_handler.store(Some(Arc::new(Mutex::new(f))));
}
async fn read_loop(
notify_rx: Arc<Notify>,
data_channel: Arc<data::data_channel::DataChannel>,
ready_state: Arc<AtomicU8>,
on_message_handler: Arc<ArcSwapOption<Mutex<OnMessageHdlrFn>>>,
on_close_handler: Arc<ArcSwapOption<Mutex<OnCloseHdlrFn>>>,
on_error_handler: Arc<ArcSwapOption<Mutex<OnErrorHdlrFn>>>,
) {
let mut buffer = vec![0u8; DATA_CHANNEL_BUFFER_SIZE as usize];
loop {
let (n, is_string) = tokio::select! {
_ = notify_rx.notified() => break,
result = data_channel.read_data_channel(&mut buffer) => {
match result{
Ok((0, _)) =>
{
ready_state.store(RTCDataChannelState::Closed as u8, Ordering::SeqCst);
let on_close_handler2 = Arc::clone(&on_close_handler);
tokio::spawn(async move {
if let Some(handler) = &*on_close_handler2.load() {
let mut f = handler.lock().await;
f().await;
}
});
break;
}
Ok((n, is_string)) => (n, is_string),
Err(err) => {
ready_state.store(RTCDataChannelState::Closed as u8, Ordering::SeqCst);
let on_error_handler2 = Arc::clone(&on_error_handler);
tokio::spawn(async move {
if let Some(handler) = &*on_error_handler2.load() {
let mut f = handler.lock().await;
f(err.into()).await;
}
});
let on_close_handler2 = Arc::clone(&on_close_handler);
tokio::spawn(async move {
if let Some(handler) = &*on_close_handler2.load() {
let mut f = handler.lock().await;
f().await;
}
});
break;
}
}
}
};
if let Some(handler) = &*on_message_handler.load() {
let mut f = handler.lock().await;
f(DataChannelMessage {
is_string,
data: Bytes::from(buffer[..n].to_vec()),
})
.await;
}
}
}
pub async fn send(&self, data: &Bytes) -> Result<usize> {
self.ensure_open()?;
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
Ok(dc.write_data_channel(data, false).await?)
} else {
Err(Error::ErrClosedPipe)
}
}
pub async fn send_text(&self, s: String) -> Result<usize> {
self.ensure_open()?;
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
Ok(dc.write_data_channel(&Bytes::from(s), true).await?)
} else {
Err(Error::ErrClosedPipe)
}
}
fn ensure_open(&self) -> Result<()> {
if self.ready_state() != RTCDataChannelState::Open {
Err(Error::ErrClosedPipe)
} else {
Ok(())
}
}
pub async fn detach(&self) -> Result<Arc<data::data_channel::DataChannel>> {
if !self.setting_engine.detach.data_channels {
return Err(Error::ErrDetachNotEnabled);
}
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
self.detach_called.store(true, Ordering::SeqCst);
Ok(Arc::clone(dc))
} else {
Err(Error::ErrDetachBeforeOpened)
}
}
pub async fn close(&self) -> Result<()> {
if self.ready_state() == RTCDataChannelState::Closed {
return Ok(());
}
self.set_ready_state(RTCDataChannelState::Closing);
self.notify_tx.notify_waiters();
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
Ok(dc.close().await?)
} else {
Ok(())
}
}
pub fn label(&self) -> &str {
self.label.as_str()
}
pub fn ordered(&self) -> bool {
self.ordered
}
pub fn max_packet_lifetime(&self) -> u16 {
self.max_packet_lifetime
}
pub fn max_retransmits(&self) -> u16 {
self.max_retransmits
}
pub fn protocol(&self) -> &str {
self.protocol.as_str()
}
pub fn negotiated(&self) -> bool {
self.negotiated
}
pub fn id(&self) -> u16 {
self.id.load(Ordering::SeqCst)
}
pub fn ready_state(&self) -> RTCDataChannelState {
self.ready_state.load(Ordering::SeqCst).into()
}
pub async fn buffered_amount(&self) -> usize {
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
dc.buffered_amount()
} else {
0
}
}
pub async fn buffered_amount_low_threshold(&self) -> usize {
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
dc.buffered_amount_low_threshold()
} else {
self.buffered_amount_low_threshold.load(Ordering::SeqCst)
}
}
pub async fn set_buffered_amount_low_threshold(&self, th: usize) {
self.buffered_amount_low_threshold
.store(th, Ordering::SeqCst);
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
dc.set_buffered_amount_low_threshold(th);
}
}
pub async fn on_buffered_amount_low(&self, f: OnBufferedAmountLowFn) {
let data_channel = self.data_channel.lock().await;
if let Some(dc) = &*data_channel {
dc.on_buffered_amount_low(f);
} else {
let mut on_buffered_amount_low = self.on_buffered_amount_low.lock().await;
*on_buffered_amount_low = Some(f);
}
}
pub(crate) fn get_stats_id(&self) -> &str {
self.stats_id.as_str()
}
pub(crate) async fn collect_stats(&self, collector: &StatsCollector) {
let stats = DataChannelStats::from(self).await;
collector.insert(self.stats_id.clone(), StatsReportType::DataChannel(stats));
}
pub(crate) fn set_ready_state(&self, r: RTCDataChannelState) {
self.ready_state.store(r as u8, Ordering::SeqCst);
}
}