feat: stop server and exit after generating

1 files changed, 26 insertions, 0 deletions

diff --git a/app/backends/servers.py b/app/backends/servers.py
index 62eadb5..965d7df 100644
--- a/app/backends/servers.py
+++ b/app/backends/servers.py
@@ -135,6 +135,28 @@ def _pid_alive(pid: int) -> bool:
     return True
 
 
+def _reap_exited(pid: int) -> bool:
+    """Reap PID when it is our exited child; True when confirmed dead.
+
+    An exited child stays visible to signal-0 probes until its parent waits
+    for it, and the hub never reaps between ``start`` and ``stop`` — so a
+    server that honored SIGTERM would still count as alive and every stop
+    would burn the whole grace period before escalating to SIGKILL. Returns
+    False when the process may still be running or was not our child (the
+    caller then falls back to its own liveness probes).
+    """
+    if not hasattr(os, "waitpid") or not hasattr(os, "WNOHANG"):
+        return False
+    try:
+        waited, _status = os.waitpid(pid, os.WNOHANG)
+    except ChildProcessError:
+        # Not our child (or someone reaped it already): not ours to judge.
+        return False
+    except OSError:
+        return False
+    return waited == pid
+
+
 def _kill_pid(pid: int) -> bool:
     """Terminate PID (and its process group on POSIX). Returns True when dead."""
     if sys.platform == "win32":
@@ -163,6 +185,10 @@ def _kill_pid(pid: int) -> bool:
     except PermissionError:
         return False
     for _ in range(int(STOP_GRACE_SECONDS * 10)):
+        # Reap first so an exited (zombie) child ends the wait immediately
+        # instead of keeping the killpg(0) probe "alive" until SIGKILL.
+        if _reap_exited(pid):
+            return True
         try:
             os.killpg(pgid, 0)
         except ProcessLookupError: