Add simple SIGINT handling

Cargo.lock

@@ -174,6 +174,7 @@ version = "0.1.0"
 dependencies = [
  "bytes",
  "futures",
+ "libc",
  "minecraft-protocol",
  "rand 0.8.4",
  "tokio",

Cargo.toml

@@ -21,6 +21,7 @@ edition = "2021"
 [dependencies]
 bytes = "1.1"
 futures = { version = "0.3", default-features = false }
+libc = "0.2"
 minecraft-protocol = { git = "https://github.com/timvisee/minecraft-protocol", rev = "c578492" }
 rand = "0.8"
-tokio = { version = "1", default-features = false, features = ["rt", "rt-multi-thread", "io-util", "net", "macros", "time", "process"] }
+tokio = { version = "1", default-features = false, features = ["rt", "rt-multi-thread", "io-util", "net", "macros", "time", "process", "signal"] }

src/config.rs

@@ -8,7 +8,7 @@ pub(crate) const ADDRESS_PUBLIC: &str = "127.0.0.1:9090";
 pub(crate) const ADDRESS_PROXY: &str = "127.0.0.1:9091";
 
 /// Server description shown when server is starting.
-pub(crate) const LABEL_SERVER_SLEEPING: &str = "☠ Server is sleeping...\n§2☻ Join to start it up";
+pub(crate) const LABEL_SERVER_SLEEPING: &str = "☠ Server is sleeping\n§2☻ Join to start it up";
 
 /// Server description shown when server is starting.
 pub(crate) const LABEL_SERVER_STARTING: &str = "§2☻ Server is starting...\n§7⌛ Please wait...";

src/main.rs

@@ -1,7 +1,8 @@
-pub mod config;
-pub mod monitor;
-pub mod protocol;
-pub mod types;
+pub(crate) mod config;
+pub(crate) mod monitor;
+pub(crate) mod protocol;
+pub(crate) mod server;
+pub(crate) mod types;
 
 use std::sync::Arc;
 
@@ -19,11 +20,10 @@ use tokio::io::AsyncReadExt;
 use tokio::io::AsyncWriteExt;
 use tokio::net::tcp::ReadHalf;
 use tokio::net::{TcpListener, TcpStream};
-use tokio::process::Command;
 
 use config::*;
-use monitor::ServerState;
 use protocol::{Client, ClientState, RawPacket};
+use server::ServerState;
 
 #[tokio::main]
 async fn main() -> Result<(), ()> {
@@ -32,7 +32,7 @@ async fn main() -> Result<(), ()> {
         ADDRESS_PUBLIC, ADDRESS_PROXY,
     );
 
-    let server_state = monitor::ServerState::default().shared();
+    let server_state = Arc::new(ServerState::default());
 
     // Listen for new connections
     // TODO: do not drop error here
@@ -42,6 +42,17 @@ async fn main() -> Result<(), ()> {
     let addr = ADDRESS_PROXY.parse().expect("invalid server IP");
     tokio::spawn(monitor::monitor_server(addr, server_state.clone()));
 
+    let sub = server_state.clone();
+    tokio::spawn(async move {
+        loop {
+            tokio::signal::ctrl_c().await.unwrap();
+            if !sub.kill_server() {
+                // TODO: gracefully kill itself instead
+                std::process::exit(1)
+            }
+        }
+    });
+
     // Proxy all incomming connections
     while let Ok((inbound, _)) = listener.accept().await {
         let client = Client::default();
@@ -164,7 +175,7 @@ async fn status_server(
             // Start server if not starting yet
             if !server.starting() {
                 server.set_starting(true);
-                tokio::spawn(start_server(server).map(|_| ()));
+                tokio::spawn(server::start(server).map(|_| ()));
             }
 
             break;
@@ -223,10 +234,10 @@ async fn status_server(
             continue;
         }
 
-        // Show unhandled packet warning
-        eprintln!("Received unhandled packet:");
-        eprintln!("- State: {:?}", client.state());
-        eprintln!("- Packet ID: {}", packet.id);
+        // // Show unhandled packet warning
+        // eprintln!("Received unhandled packet:");
+        // eprintln!("- State: {:?}", client.state());
+        // eprintln!("- Packet ID: {}", packet.id);
     }
 
     // Gracefully close connection
@@ -259,18 +270,3 @@ async fn proxy(mut inbound: TcpStream, addr_target: String) -> Result<(), ()> {
 
     Ok(())
 }
-
-/// Start Minecraft server.
-async fn start_server(state: Arc<ServerState>) -> Result<(), Box<dyn std::error::Error>> {
-    let mut cmd = Command::new(SERVER_CMD);
-
-    let status = cmd.status().await?;
-
-    println!("Server exited, status: {}", status);
-
-    // Reset online and starting state
-    state.set_online(false);
-    state.set_starting(false);
-
-    Ok(())
-}

src/monitor.rs

@@ -1,7 +1,6 @@
 // TODO: remove all unwraps/expects here!
 
 use std::net::SocketAddr;
-use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Arc;
 use std::time::Duration;
 
@@ -15,6 +14,7 @@ use tokio::io::AsyncWriteExt;
 use tokio::net::TcpStream;
 
 use crate::protocol::{self, ClientState, RawPacket};
+use crate::server::ServerState;
 
 /// Minecraft protocol version used when polling server status.
 const PROTOCOL_VERSION: i32 = 754;
@@ -25,43 +25,6 @@ const MONITOR_PING_INTERVAL: u64 = 2;
 /// Ping timeout in seconds.
 const PING_TIMEOUT: u64 = 8;
 
-/// Shared server state.
-#[derive(Default, Debug)]
-pub struct ServerState {
-    /// Whether the server is online.
-    online: AtomicBool,
-
-    /// Whether the server is starting.
-    starting: AtomicBool,
-}
-
-impl ServerState {
-    /// Transform into shared instance.
-    pub fn shared(self) -> Arc<Self> {
-        Arc::new(self)
-    }
-
-    /// Whether the server is online.
-    pub fn online(&self) -> bool {
-        self.online.load(Ordering::Relaxed)
-    }
-
-    /// Set whether the server is online.
-    pub fn set_online(&self, online: bool) {
-        self.online.store(online, Ordering::Relaxed)
-    }
-
-    /// Whether the server is starting.
-    pub fn starting(&self) -> bool {
-        self.starting.load(Ordering::Relaxed)
-    }
-
-    /// Set whether the server is starting.
-    pub fn set_starting(&self, starting: bool) {
-        self.starting.store(starting, Ordering::Relaxed)
-    }
-}
-
 /// Poll server state.
 ///
 /// Returns `true` if a ping succeeded.

src/protocol.rs

@@ -46,10 +46,10 @@ impl ClientState {
     /// From state ID.
     pub fn from_id(id: i32) -> Option<Self> {
         match id {
-            // 0 => Self::Handshake,
+            0 => Some(Self::Handshake),
             1 => Some(Self::Status),
             2 => Some(Self::Login),
-            // 2 => Self::Play,
+            3 => Some(Self::Play),
             _ => None,
         }
     }
@@ -57,10 +57,10 @@ impl ClientState {
     /// Get state ID.
     pub fn to_id(self) -> i32 {
         match self {
-            Self::Handshake => unimplemented!(),
+            Self::Handshake => 0,
             Self::Status => 1,
             Self::Login => 2,
-            Self::Play => unimplemented!(),
+            Self::Play => 3,
         }
     }
 }

src/server.rs

@@ -0,0 +1,92 @@
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{Arc, Mutex};
+
+use tokio::process::Command;
+
+use crate::config::SERVER_CMD;
+
+/// Shared server state.
+#[derive(Default, Debug)]
+pub struct ServerState {
+    /// Whether the server is online.
+    online: AtomicBool,
+
+    /// Whether the server is starting.
+    starting: AtomicBool,
+
+    /// Server PID.
+    pid: Mutex<Option<u32>>,
+}
+
+impl ServerState {
+    /// Whether the server is online.
+    pub fn online(&self) -> bool {
+        self.online.load(Ordering::Relaxed)
+    }
+
+    /// Set whether the server is online.
+    pub fn set_online(&self, online: bool) {
+        self.online.store(online, Ordering::Relaxed)
+    }
+
+    /// Whether the server is starting.
+    pub fn starting(&self) -> bool {
+        self.starting.load(Ordering::Relaxed)
+    }
+
+    /// Set whether the server is starting.
+    pub fn set_starting(&self, starting: bool) {
+        self.starting.store(starting, Ordering::Relaxed)
+    }
+
+    /// Kill any running server.
+    pub fn kill_server(&self) -> bool {
+        if let Some(pid) = *self.pid.lock().unwrap() {
+            eprintln!("[lazymc] Sending kill signal to server");
+            kill_gracefully(pid);
+            return true;
+        }
+
+        false
+    }
+
+    /// Set server PID.
+    pub fn set_pid(&self, pid: Option<u32>) {
+        *self.pid.lock().unwrap() = pid;
+    }
+}
+
+/// Start Minecraft server.
+pub async fn start(state: Arc<ServerState>) -> Result<(), Box<dyn std::error::Error>> {
+    let mut cmd = Command::new(SERVER_CMD);
+
+    eprintln!("[lazymc] Starting server...");
+    let mut child = cmd.spawn()?;
+
+    state.set_pid(Some(child.id().expect("unknown server PID")));
+
+    let status = child.wait().await?;
+    eprintln!("[lazymc] Server stopped (status: {})\n", status);
+
+    // Reset online and starting state
+    // TODO: also set this when returning early due to error
+    state.set_pid(None);
+    state.set_online(false);
+    state.set_starting(false);
+
+    Ok(())
+}
+
+/// Gracefully kill process.
+fn kill_gracefully(pid: u32) {
+    #[cfg(unix)]
+    unsafe {
+        libc::kill(pid as i32, libc::SIGINT);
+    }
+
+    #[cfg(not(unix))]
+    {
+        // TODO: implement this for Windows
+        unimplemented!();
+    }
+}