transport: Introduce common listener for tcp and websocket (#147)

This PR aims to remove duplicated code for socket listener between TCP
and WebSocket transports.

Changes done:
- Extended code logic to facilitate both TCP and WebSockets
- Moved the listener code to a dedicated `common` module
- Provided fairness for polling the listener stream by introducing a
rotating index
- Traits to convert between multiaddr <-> socket addr
- Removed unnecessary cloning of listen addresses 

Part of #70.

---------

Signed-off-by: Alexandru Vasile <[email protected]>

src/transport/common/mod.rs

@@ -0,0 +1,23 @@
+// Copyright 2024 litep2p developers
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+//! Shared transport protocol implementation
+
+pub mod listener;

src/transport/mod.rs

@@ -27,6 +27,7 @@ use multiaddr::Multiaddr;
 
 use std::{fmt::Debug, time::Duration};
 
+pub(crate) mod common;
 pub mod quic;
 pub mod tcp;
 pub mod webrtc;

src/transport/tcp/config.rs

@@ -65,13 +65,13 @@ pub struct Config {
     /// By default the value is set to `2` which means that the `NoiseSocket` will allocate
     /// `130 KB` for each outgoing connection.
     ///
-    /// The write buffer size is separate from  the read-ahead frame count so by default
+    /// The write buffer size is separate from the read-ahead frame count so by default
     /// the Noise code will allocate `2 * 65 KB + 5 * 65 KB = 455 KB` per connection.
     pub noise_write_buffer_size: usize,
 
     /// Connection open timeout.
     ///
-    /// How long should litep2p wait for a connection to be opend before the host
+    /// How long should litep2p wait for a connection to be opened before the host
     /// is deemed unreachable.
     pub connection_open_timeout: std::time::Duration,
 

src/transport/tcp/connection.rs

@@ -28,10 +28,7 @@ use crate::{
     multistream_select::{dialer_select_proto, listener_select_proto, Negotiated, Version},
     protocol::{Direction, Permit, ProtocolCommand, ProtocolSet},
     substream,
-    transport::{
-        tcp::{listener::AddressType, substream::Substream},
-        Endpoint,
-    },
+    transport::{common::listener::AddressType, tcp::substream::Substream, Endpoint},
     types::{protocol::ProtocolName, ConnectionId, SubstreamId},
     BandwidthSink, PeerId,
 };