Create TCP listener

Cargo.lock

@@ -1275,6 +1275,7 @@ dependencies = [
  "librqbit-dht",
  "librqbit-peer-protocol",
  "librqbit-sha1-wrapper",
+ "librqbit-upnp",
  "openssl",
  "parking_lot",
  "rand",

crates/librqbit/Cargo.toml

@@ -29,6 +29,7 @@ clone_to_owned = {path = "../clone_to_owned", package="librqbit-clone-to-owned",
 peer_binary_protocol = {path = "../peer_binary_protocol", package="librqbit-peer-protocol", version = "3.2.1"}
 sha1w = {path = "../sha1w", default-features=false, package="librqbit-sha1-wrapper", version="2.2.1"}
 dht = {path = "../dht", package="librqbit-dht", version="4.0.0"}
+librqbit-upnp = {path = "../upnp", version = "0.1.0"}
 
 tokio = {version = "1", features = ["macros", "rt-multi-thread"]}
 axum = {version = "0.7"}

crates/librqbit/src/session.rs

@@ -23,6 +23,7 @@ use parking_lot::RwLock;
 use reqwest::Url;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use serde_with::serde_as;
+use tokio::net::TcpListener;
 use tracing::{debug, error, error_span, info, warn};
 
 use crate::{
@@ -147,6 +148,9 @@ pub struct Session {
     spawner: BlockingSpawner,
     db: RwLock<SessionDatabase>,
     output_folder: PathBuf,
+
+    cancel_tx: tokio::sync::watch::Sender<()>,
+    cancel_rx: tokio::sync::watch::Receiver<()>,
 }
 
 async fn torrent_from_url(url: &str) -> anyhow::Result<TorrentMetaV1Owned> {
@@ -322,6 +326,23 @@ pub struct SessionOptions {
     pub peer_id: Option<Id20>,
     /// Configure default peer connection options. Can be overriden per torrent.
     pub peer_opts: Option<PeerConnectionOptions>,
+
+    pub listen_port_range: Option<std::ops::Range<u16>>,
+    pub enable_upnp_port_forwarding: bool,
+}
+
+async fn create_tcp_listener(
+    port_range: std::ops::Range<u16>,
+) -> anyhow::Result<(TcpListener, u16)> {
+    for port in port_range.clone() {
+        match TcpListener::bind(("0.0.0.0", port)).await {
+            Ok(l) => return Ok((l, port)),
+            Err(e) => {
+                debug!("error listening on port {port}: {e:#}")
+            }
+        }
+    }
+    bail!("no free TCP ports in range {port_range:?}");
 }
 
 impl Session {
@@ -336,6 +357,16 @@ impl Session {
         opts: SessionOptions,
     ) -> anyhow::Result<Arc<Self>> {
         let peer_id = opts.peer_id.unwrap_or_else(generate_peer_id);
+
+        let (tcp_listener, port) = if let Some(port_range) = opts.listen_port_range {
+            let (l, p) = create_tcp_listener(port_range)
+                .await
+                .context("error listening on TCP")?;
+            (Some(l), Some(p))
+        } else {
+            (None, None)
+        };
+
         let dht = if opts.disable_dht {
             None
         } else {
@@ -355,6 +386,9 @@ impl Session {
                 .join("session.json"),
         };
         let spawner = BlockingSpawner::default();
+
+        let (cancel_tx, cancel_rx) = tokio::sync::watch::channel(());
+
         let session = Arc::new(Self {
             persistence_filename,
             peer_id,
@@ -363,8 +397,28 @@ impl Session {
             spawner,
             output_folder,
             db: RwLock::new(Default::default()),
+            cancel_rx,
+            cancel_tx,
         });
 
+        if let Some(tcp_listener) = tcp_listener {
+            session.spawn(
+                "tcp listener",
+                error_span!("tcp_listen", port = port),
+                session.clone().task_tcp_listener(tcp_listener),
+            );
+        }
+
+        if let Some(listen_port) = port {
+            if opts.enable_upnp_port_forwarding {
+                session.spawn(
+                    "upnp_forward",
+                    error_span!("upnp_forward", port = listen_port),
+                    session.clone().task_upnp_port_forwarder(listen_port),
+                );
+            }
+        }
+
         if opts.persistence {
             info!(
                 "will use {:?} for session persistence",
@@ -375,36 +429,50 @@ impl Session {
                     format!("couldn't create directory {:?} for session storage", parent)
                 })?;
             }
-            let session = session.clone();
-            spawn(
+            let persistence_task = session.clone().task_persistence();
+            session.spawn(
                 "session persistene",
                 error_span!("session_persistence"),
-                async move {
-                    // Populate initial from the state filename
-                    if let Err(e) = session.populate_from_stored().await {
-                        error!("could not populate session from stored file: {:?}", e);
-                    }
-
-                    let session = Arc::downgrade(&session);
-
-                    loop {
-                        tokio::time::sleep(Duration::from_secs(10)).await;
-                        let session = match session.upgrade() {
-                            Some(s) => s,
-                            None => break,
-                        };
-                        if let Err(e) = session.dump_to_disk() {
-                            error!("error dumping session to disk: {:?}", e);
-                        }
-                    }
-
-                    Ok(())
-                },
+                persistence_task,
             );
         }
 
         Ok(session)
     }
+
+    async fn task_persistence(self: Arc<Self>) -> anyhow::Result<()> {
+        // Populate initial from the state filename
+        if let Err(e) = self.populate_from_stored().await {
+            error!("could not populate session from stored file: {:?}", e);
+        }
+
+        let session = Arc::downgrade(&self);
+        drop(self);
+
+        loop {
+            tokio::time::sleep(Duration::from_secs(10)).await;
+            let session = match session.upgrade() {
+                Some(s) => s,
+                None => break,
+            };
+            if let Err(e) = session.dump_to_disk() {
+                error!("error dumping session to disk: {:?}", e);
+            }
+        }
+
+        Ok(())
+    }
+
+    async fn task_tcp_listener(self: Arc<Self>, l: TcpListener) -> anyhow::Result<()> {
+        // TODO
+        Ok(())
+    }
+
+    async fn task_upnp_port_forwarder(self: Arc<Self>, port: u16) -> anyhow::Result<()> {
+        let pf = librqbit_upnp::UpnpPortForwarder::new(vec![port], None)?;
+        pf.run_forever().await
+    }
+
     pub fn get_dht(&self) -> Option<&Dht> {
         self.dht.as_ref()
     }
@@ -425,6 +493,24 @@ impl Session {
         }
     }
 
+    fn spawn(
+        &self,
+        name: &str,
+        span: tracing::Span,
+        fut: impl std::future::Future<Output = anyhow::Result<()>> + Send + 'static,
+    ) {
+        let mut cancel_rx = self.cancel_rx.clone();
+        spawn(name, span, async move {
+            tokio::select! {
+                r = fut => r,
+                _ = cancel_rx.changed() => {
+                    debug!("task canceled");
+                    Ok(())
+                }
+            }
+        });
+    }
+
     async fn populate_from_stored(self: &Arc<Self>) -> anyhow::Result<()> {
         let mut rdr = match std::fs::File::open(&self.persistence_filename) {
             Ok(f) => BufReader::new(f),