From 7a26b7c0116d00441e1cca38861ad1469b714e56 Mon Sep 17 00:00:00 2001
From: dece <shgck@pistache.land>
Date: Fri, 17 Dec 2021 19:54:54 +0100
Subject: [PATCH] listen on multiple addresses concurrently

---
 README.md   | 10 +++++++---
 src/main.rs | 49 ++++++++++++++++++++++++++++++++-----------------
 2 files changed, 39 insertions(+), 20 deletions(-)

diff --git a/README.md b/README.md
index 13001c7..2e501e8 100644
--- a/README.md
+++ b/README.md
@@ -27,13 +27,18 @@ Usage
 Use `opal -h` to get a list of options. There is no config file, every setting
 can be configured from the command line.
 
-- `-a, --address <address>`: specify the address to listen to.
+- `-a, --address <address>`: specify the address(es) to listen to.
 - `-c, --cert <cert>`: server certificate path.
 - `-k, --key <key>`: server private key path.
 - `-r, --root-path <root_path>`: path to CGI scripts root.
 - `-e, --env <key=value>`: additional environment variables for CGI scripts;
     this option can be used multiple times.
 
+You can specify multiple addresses to listen to by using several `-a` options.
+Note that if you just want to listen to both IPv4 and IPv6 on any interface,
+listening only on `[::]:1965` should suffice for systems with dual-stack
+enabled (default on many Linux systems, maybe not BSD).
+
 
 
 CGI support
@@ -103,9 +108,8 @@ Roadmap
 
 Things to consider:
 
-- Multiple listening addresses, at least so we can easily listen on both IPv4
-    and IPv6.
 - Support SCGI; a bit more complex but should save resources on smol hardware.
+- Chroot; quite cheap and can bring a bit of peace of mind.
 
 Things that probably won't be considered:
 
diff --git a/src/main.rs b/src/main.rs
index b119f98..6d9e78b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -41,7 +41,8 @@ fn run() -> Result<(), i32> {
                 .short("a")
                 .long("address")
                 .help("Address to listen to")
-                .takes_value(true),
+                .takes_value(true)
+                .multiple(true),
         )
         .arg(
             clap::Arg::with_name("cert")
@@ -110,24 +111,38 @@ fn run() -> Result<(), i32> {
     )
     .map_err(|err| run_failure("Can't create TLS acceptor", &err))?;
 
-    let address = matches.value_of("address").unwrap();
-    let listener = net::TcpListener::bind(address)
-        .map_err(|err| run_failure("Can't create TCP listener", &err))?;
-
-    for stream in listener.incoming() {
-        match stream {
-            Ok(stream) => {
-                let acceptor = acceptor.clone();
-                let cgi_config = cgi_config.clone();
-                thread::spawn(move || match acceptor.accept(stream) {
-                    Ok(mut tls_stream) => handle_client(&mut tls_stream, &cgi_config),
-                    Err(err) => error!("Can't initiate TLS stream: {}", err),
-                });
-            }
+    let mut threads = vec![];
+    for address in matches.values_of("address").unwrap() {
+        let listener = match net::TcpListener::bind(address) {
+            Ok(l) => l,
             Err(err) => {
-                error!("Can't accept connection: {}", err);
+                error!("Can't create TCP listener: {}", &err);
+                continue
             }
-        }
+        };
+        info!("Listening on {}", address);
+        let acceptor = acceptor.clone();
+        let cgi_config = cgi_config.clone();
+        threads.push(thread::spawn(move || {
+            for stream in listener.incoming() {
+                match stream {
+                    Ok(stream) => {
+                        let acceptor = acceptor.clone();
+                        let cgi_config = cgi_config.clone();
+                        thread::spawn(move || match acceptor.accept(stream) {
+                            Ok(mut tls_stream) => handle_client(&mut tls_stream, &cgi_config),
+                            Err(err) => error!("Can't initiate TLS stream: {}", err),
+                        });
+                    }
+                    Err(err) => {
+                        error!("Can't accept connection: {}", err);
+                    }
+                }
+            }
+        }));
+    }
+    for t in threads.into_iter() {
+        t.join().unwrap();
     }
     Ok(())
 }