From a1e7565f21e4696029a1b7b72d9a3d7143adcd85 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20LIARD?= <cliard@a00.fr>
Date: Sun, 26 Jul 2026 11:48:59 +0200
Subject: [PATCH] fix(cli): make grob stop recognise its daemon on macOS
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`command_invokes_grob` split the process command line only on NUL. That fits
Linux `/proc/<pid>/cmdline` (`grob\0start\0`) but not macOS `ps -o command=`,
which is space-separated (`/opt/homebrew/bin/grob start`). The whole string
then reached `Path::file_name`, yielding `"grob start"` (≠ `"grob"`), so
`is_process_running` returned false for a live daemon and `grob stop` / the
restart path in `grob start` both refused to act — the daemon could not be
stopped or cleanly restarted on macOS.

Pick the separator by which one is present: NUL when the string contains it
(Linux), whitespace otherwise (macOS). Existing negative cases still hold
(`grob-upgrade`, `python …/grob.py`, `agrob-helper`).

Verified end to end: a daemon started with the fixed binary is now stopped by
`grob stop` ("Service stopped successfully") instead of "refusing to stop".

Note: the pid file is a single global `~/.grob/grob.pid` (one-daemon model), so
with identity now working, `grob start` on any port stops whatever that file
points at. Running a second daemon on another port therefore replaces the first
— expected for the single-daemon design, but worth knowing.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 src/shared/pid.rs | 32 ++++++++++++++++++++++++++------
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/src/shared/pid.rs b/src/shared/pid.rs
index 3fe920a..69eef5a 100644
--- a/src/shared/pid.rs
+++ b/src/shared/pid.rs
@@ -135,12 +135,19 @@ pub fn is_process_running(pid: u32) -> bool {
 
 #[cfg(feature = "unix-signals")]
 fn command_invokes_grob(command: &str) -> bool {
-    let first_arg = command
-        .split('\0')
-        .find(|part| !part.trim().is_empty())
-        .or_else(|| command.split_whitespace().next())
-        .unwrap_or_default()
-        .trim();
+    // The command string arrives in two shapes: Linux `/proc/<pid>/cmdline` is
+    // NUL-separated (`grob\0start\0`), while macOS `ps -o command=` is
+    // space-separated (`/opt/homebrew/bin/grob start`). Splitting only on `\0`
+    // left the macOS form intact, so `Path::file_name` on
+    // `"…/grob start"` returned `"grob start"` (≠ `"grob"`) and `grob stop`
+    // refused to stop its own daemon. Pick the separator by which one is present.
+    let first_arg = if command.contains('\0') {
+        command.split('\0').next()
+    } else {
+        command.split_whitespace().next()
+    }
+    .unwrap_or_default()
+    .trim();
     let executable = std::path::Path::new(first_arg)
         .file_name()
         .and_then(|name| name.to_str())
@@ -191,4 +198,17 @@ mod tests {
         assert!(!command_invokes_grob("/usr/bin/python /tmp/grob.py"));
         assert!(!command_invokes_grob("/usr/bin/agrob-helper"));
     }
+
+    /// macOS `ps -o command=` is space-separated; the executable and its args
+    /// must not be read as one path component. This is the exact string that
+    /// made `grob stop` refuse to stop a live daemon.
+    #[cfg(feature = "unix-signals")]
+    #[test]
+    fn command_identity_accepts_space_separated_macos_form() {
+        assert!(command_invokes_grob("/opt/homebrew/bin/grob start"));
+        assert!(command_invokes_grob("/opt/homebrew/bin/grob start\n"));
+        assert!(command_invokes_grob("grob start -d"));
+        // A non-grob program with a grob-ish argument still must not match.
+        assert!(!command_invokes_grob("/usr/bin/python grob start"));
+    }
 }