1 files changed, 68 insertions, 6 deletions

diff --git a/src/platform/linux.rs b/src/platform/linux.rs
index 001ef03e..10695e92 100644
--- a/src/platform/linux.rs
+++ b/src/platform/linux.rs
@@ -1,8 +1,51 @@
 use std::path::PathBuf;
 
-/// Get the foreground process name for a given child PID.
-/// Uses /proc/<pid>/stat to find the tpgid, then /proc/<tpgid>/comm.
-pub fn foreground_process_name(child_pid: u32) -> Option<String> {
+use super::{ForegroundJob, ForegroundProcess};
+
+/// Collect the foreground terminal job for a given child PID.
+pub fn foreground_job(child_pid: u32) -> Option<ForegroundJob> {
+    let tpgid = foreground_pgid(child_pid)? as u32;
+    let mut processes = Vec::new();
+
+    for entry in std::fs::read_dir("/proc").ok()? {
+        let entry = entry.ok()?;
+        let file_name = entry.file_name();
+        let pid_str = file_name.to_str()?;
+        if !pid_str.bytes().all(|b| b.is_ascii_digit()) {
+            continue;
+        }
+
+        let pid: u32 = match pid_str.parse() {
+            Ok(pid) => pid,
+            Err(_) => continue,
+        };
+
+        let Some((pgrp, name)) = process_pgrp_and_comm(pid) else {
+            continue;
+        };
+        if pgrp as u32 != tpgid {
+            continue;
+        }
+
+        processes.push(ForegroundProcess {
+            pid,
+            name,
+            argv0: None,
+            cmdline: process_cmdline(pid),
+        });
+    }
+
+    if processes.is_empty() {
+        return None;
+    }
+
+    Some(ForegroundJob {
+        process_group_id: tpgid,
+        processes,
+    })
+}
+
+fn foreground_pgid(child_pid: u32) -> Option<i32> {
     // /proc/<pid>/stat format: "pid (comm) state ppid pgrp session tty_nr tpgid ..."
     // The (comm) field can contain spaces and parens, so we find the last ')' first.
     let stat = std::fs::read_to_string(format!("/proc/{child_pid}/stat")).ok()?;
@@ -10,11 +53,30 @@ pub fn foreground_process_name(child_pid: u32) -> Option<String> {
     let fields: Vec<&str> = rest.split_whitespace().collect();
     // After (comm): state(0) ppid(1) pgrp(2) session(3) tty_nr(4) tpgid(5)
     let tpgid: i32 = fields.get(5)?.parse().ok()?;
-    if tpgid <= 0 {
+    (tpgid > 0).then_some(tpgid)
+}
+
+fn process_pgrp_and_comm(pid: u32) -> Option<(i32, String)> {
+    let stat = std::fs::read_to_string(format!("/proc/{pid}/stat")).ok()?;
+    let close = stat.rfind(')')?;
+    let comm = stat.get(1 + stat.find('(')?..close)?.to_string();
+    let rest = stat.get(close + 2..)?;
+    let fields: Vec<&str> = rest.split_whitespace().collect();
+    let pgrp: i32 = fields.get(2)?.parse().ok()?;
+    Some((pgrp, comm))
+}
+
+fn process_cmdline(pid: u32) -> Option<String> {
+    let bytes = std::fs::read(format!("/proc/{pid}/cmdline")).ok()?;
+    if bytes.is_empty() {
         return None;
     }
-    let comm = std::fs::read_to_string(format!("/proc/{tpgid}/comm")).ok()?;
-    Some(comm.trim().to_string())
+    let parts: Vec<String> = bytes
+        .split(|&b| b == 0)
+        .filter(|part| !part.is_empty())
+        .map(|part| String::from_utf8_lossy(part).into_owned())
+        .collect();
+    (!parts.is_empty()).then(|| parts.join(" "))
 }
 
 /// Get the current working directory of a process.