Add nix crate, use it for signaling

Cargo.lock

@@ -912,6 +912,7 @@ dependencies = [
  "md-5",
  "minecraft-protocol",
  "named-binary-tag",
+ "nix",
  "notify",
  "pretty_env_logger",
  "proxy-protocol",
@@ -981,6 +982,15 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
 
+[[package]]
+name = "memoffset"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5de893c32cde5f383baa4c04c5d6dbdd735cfd4a794b0debdb2bb1b421da5ff4"
+dependencies = [
+ "autocfg 1.1.0",
+]
+
 [[package]]
 name = "minecraft-protocol"
 version = "0.1.0"
@@ -1090,6 +1100,20 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "nix"
+version = "0.26.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46a58d1d356c6597d08cde02c2f09d785b09e28711837b1ed667dc652c08a694"
+dependencies = [
+ "bitflags",
+ "cfg-if 1.0.0",
+ "libc",
+ "memoffset",
+ "pin-utils",
+ "static_assertions",
+]
+
 [[package]]
 name = "notify"
 version = "4.0.17"
@@ -1574,6 +1598,12 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "static_assertions"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
+
 [[package]]
 name = "strsim"
 version = "0.10.0"

Cargo.toml

@@ -80,6 +80,7 @@ async-std = { version = "1.9.0", default-features = false, optional = true }
 # Feature: lobby
 md-5 = { version = "0.10", optional = true }
 uuid = { version = "0.7", optional = true, features = ["v3"] }
+nix = "0.26"
 
 [target.'cfg(unix)'.dependencies]
 libc = "0.2"

src/os/mod.rs

@@ -1,17 +1,15 @@
-#[cfg(unix)]
-pub mod unix;
 #[cfg(windows)]
 pub mod windows;
 
+use nix::{sys::signal, unistd::Pid};
+
 /// Force kill process.
 ///
 /// Results in undefined behavior if PID is invalid.
 #[allow(unreachable_code)]
 pub fn force_kill(pid: u32) -> bool {
     #[cfg(unix)]
-    unsafe {
+    return signal::kill(Pid::from_raw(pid as i32), signal::SIGKILL) == Ok(());
-        return unix::force_kill(pid);
-    }
 
     #[cfg(windows)]
     unsafe {
@@ -22,18 +20,14 @@ pub fn force_kill(pid: u32) -> bool {
 }
 
 /// Gracefully kill process.
-///
 /// Results in undefined behavior if PID is invalid.
 ///
 /// # Panics
-///
 /// Panics on platforms other than Unix.
 #[allow(unreachable_code, dead_code, unused_variables)]
 pub fn kill_gracefully(pid: u32) -> bool {
     #[cfg(unix)]
-    unsafe {
+    return signal::kill(Pid::from_raw(pid as i32), signal::SIGTERM) == Ok(());
-        return unix::kill_gracefully(pid);
-    }
 
     unimplemented!(
         "gracefully killing Minecraft server process not implemented on non-Unix platforms"
@@ -48,9 +42,7 @@ pub fn kill_gracefully(pid: u32) -> bool {
 #[allow(unreachable_code)]
 pub fn freeze(pid: u32) -> bool {
     #[cfg(unix)]
-    unsafe {
+    return signal::kill(Pid::from_raw(pid as i32), signal::SIGSTOP) == Ok(());
-        return unix::freeze(pid);
-    }
 
     unimplemented!(
         "Freezing the Minecraft server process is not implemented on non-Unix platforms."
@@ -65,9 +57,7 @@ pub fn freeze(pid: u32) -> bool {
 #[allow(unreachable_code)]
 pub fn unfreeze(pid: u32) -> bool {
     #[cfg(unix)]
-    unsafe {
+    return signal::kill(Pid::from_raw(pid as i32), signal::SIGCONT) == Ok(());
-        return unix::unfreeze(pid);
-    }
 
     unimplemented!(
         "Unfreezing the Minecraft server process is not implemented on non-Unix platforms."

src/os/unix.rs

@@ -1,55 +0,0 @@
-/// Force kill process on Unix by sending `SIGKILL`.
-///
-/// This is unsafe because the PID isn't checked.
-pub unsafe fn force_kill(pid: u32) -> bool {
-    debug!(target: "lazymc", "Sending SIGKILL signal to {pid} to kill server");
-    let result = libc::kill(pid as i32, libc::SIGKILL);
-
-    if result != 0 {
-        trace!(target: "lazymc", "SIGKILL failed: {result}");
-    }
-
-    result == 0
-}
-
-/// Gracefully kill process on Unix by sending `SIGTERM`.
-///
-/// This is unsafe because the PID isn't checked.
-pub unsafe fn kill_gracefully(pid: u32) -> bool {
-    debug!(target: "lazymc", "Sending SIGTERM signal to {pid} to kill server");
-    let result = libc::kill(pid as i32, libc::SIGTERM);
-
-    if result != 0 {
-        warn!(target: "lazymc", "Sending SIGTERM signal to server failed: {result}");
-    }
-
-    result == 0
-}
-
-/// Freeze process on Unix by sending `SIGSTOP`.
-///
-/// This is unsaft because the PIS isn't checked.
-pub unsafe fn freeze(pid: u32) -> bool {
-    debug!(target: "lazymc", "Sending SIGSTOP signal to {pid} to kill server");
-    let result = libc::kill(pid as i32, libc::SIGSTOP);
-
-    if result != 0 {
-        warn!(target: "lazymc", "Sending SIGSTOP signal to server failed: {result}");
-    }
-
-    result == 0
-}
-
-/// Unfreeze process on Unix by sending `SIGCONT`.
-///
-/// This is unsaft because the PIS isn't checked.
-pub unsafe fn unfreeze(pid: u32) -> bool {
-    debug!(target: "lazymc", "Sending SIGCONT signal to {pid} to unfreeze server");
-    let result = libc::kill(pid as i32, libc::SIGCONT);
-
-    if result != 0 {
-        warn!(target: "lazymc", "Sending SIGCONT signal to server failed: {result}");
-    }
-
-    result == 0
-}