fix: respect ign for tstp, fix helix-editor#3321

helix-term/Cargo.toml

@@ -43,6 +43,7 @@ signal-hook = "0.3"
 tokio-stream = "0.1"
 futures-util = { version = "0.3", features = ["std", "async-await"], default-features = false }
 arc-swap = { version = "1.5.1" }
+libc = "0.2"
 
 # Logging
 fern = "0.6"

helix-term/src/application.rs

@@ -43,6 +43,8 @@ type Signals = futures_util::stream::Empty<()>;
 
 const LSP_DEADLINE: Duration = Duration::from_millis(16);
 
+pub static mut ENABLE_SIGTSTP: bool = true;
+
 pub struct Application {
     compositor: Compositor,
     pub editor: Editor,
@@ -205,9 +207,19 @@ impl Application {
 
         #[cfg(windows)]
         let signals = futures_util::stream::empty();
+
+        let mut app_signals = vec![signal::SIGTSTP, signal::SIGCONT];
+        unsafe {
+            // If SIGTSTP is SIG_IGN, then do not listen for it
+            let tstp = libc::signal(signal_hook::consts::SIGTSTP, /*SIG_IGN*/ 1);
+            if tstp != /*SIG_ERR*/ 0 {
+                log::debug!("Disabling SIGTSTP, C-z will not suspend Helix");
+                ENABLE_SIGTSTP = false;
+                app_signals.remove(0);
+            }
+        }
         #[cfg(not(windows))]
-        let signals =
-            Signals::new(&[signal::SIGTSTP, signal::SIGCONT]).context("build signal handler")?;
+        let signals = Signals::new(app_signals).context("build signal handler")?;
 
         let app = Self {
             compositor,

helix-term/src/commands.rs

@@ -4647,8 +4647,12 @@ fn shell_prompt(cx: &mut Context, prompt: Cow<'static, str>, behavior: ShellBeha
 }
 
 fn suspend(_cx: &mut Context) {
-    #[cfg(not(windows))]
-    signal_hook::low_level::raise(signal_hook::consts::signal::SIGTSTP).unwrap();
+    unsafe {
+        if crate::application::ENABLE_SIGTSTP {
+            #[cfg(not(windows))]
+            signal_hook::low_level::raise(signal_hook::consts::signal::SIGTSTP).unwrap();
+        }
+    }
 }
 
 fn add_newline_above(cx: &mut Context) {