Run application and open command detached from server process

Fixes server being unkillable because of invoked application that is still running

rust/server/Cargo.toml

@@ -42,6 +42,9 @@ bytes = "1.6.0"
 scenario_runner = { path = "../scenario_runner", optional = true }
 itertools = "0.10.5"
 
+[target.'cfg(any(target_os = "linux", target_os = "macos"))'.dependencies]
+libc = "0.2.153"
+
 [target.'cfg(target_os = "linux")'.dependencies]
 freedesktop_entry_parser = "1.3"
 freedesktop-icons = "0.2"

rust/server/src/plugins/applications/mod.rs

@@ -1,9 +1,8 @@
+use image::ImageFormat;
+use image::imageops::FilterType;
 
 #[cfg(target_os = "linux")]
 mod linux;
-
-use image::ImageFormat;
-use image::imageops::FilterType;
 #[cfg(target_os = "linux")]
 pub use linux::get_apps;
 

rust/server/src/plugins/js/plugins/applications.rs

@@ -1,8 +1,5 @@
-use std::path::Path;
-
 use deno_core::op;
 use tokio::task::spawn_blocking;
-
 use crate::plugins::applications::{DesktopEntry, get_apps};
 
 #[op]
@@ -15,9 +12,50 @@ fn open_application(command: Vec<String>) -> anyhow::Result<()> {
     let path = &command[0];
     let args = &command[1..];
 
-    std::process::Command::new(Path::new(path))
-        .args(args)
-        .spawn()?;
+    #[cfg(not(windows))]
+    spawn_detached(path, args)?;
 
     Ok(())
 }
+
+#[cfg(not(windows))]
+pub fn spawn_detached<I, S>(
+    path: &str,
+    args: I,
+) -> std::io::Result<()>
+where
+    I: IntoIterator<Item = S> + Copy,
+    S: AsRef<std::ffi::OsStr>,
+{
+    // from https://github.com/alacritty/alacritty/blob/5abb4b73937b17fe501b9ca20b602950f1218b96/alacritty/src/daemon.rs#L65
+    use std::os::unix::prelude::CommandExt;
+    use std::process::{Command, Stdio};
+
+    let mut command = Command::new(path);
+
+    command
+        .args(args)
+        .stdin(Stdio::null())
+        .stdout(Stdio::null())
+        .stderr(Stdio::null());
+
+    unsafe {
+        command
+            .pre_exec(|| {
+                match libc::fork() {
+                    -1 => return Err(std::io::Error::last_os_error()),
+                    0 => (),
+                    _ => libc::_exit(0),
+                }
+
+                if libc::setsid() == -1 {
+                    return Err(std::io::Error::last_os_error());
+                }
+
+                Ok(())
+            })
+            .spawn()?
+            .wait()
+            .map(|_| ())
+    }
+}

rust/server/src/plugins/mod.rs

@@ -416,7 +416,7 @@ impl ApplicationManager {
     }
 
     pub fn handle_open(&self, href: String) {
-        match open::that(&href) {
+        match open::that_detached(&href) {
             Ok(()) => tracing::info!("Opened '{}' successfully.", href),
             Err(err) => tracing::error!("An error occurred when opening '{}': {}", href, err),
         }