From aaa34e0a644912e49d7c5619749b67f585da9c85 Mon Sep 17 00:00:00 2001
From: Max Romanov <max.romanov@nginx.com>
Date: Wed, 24 Nov 2021 13:11:50 +0300
Subject: [PATCH] Fixing zombie process appearance and hang up on shutdown.

After the c8790d2a89bb commit, the SIGCHLD handler may return before processing
all awaiting PIDs.  To avoid zombie processes and ensure successful main
process termination, waitpid() must be called until an error is returned.

This closes #600 issue on GitHub.
---
 src/nxt_main_process.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/nxt_main_process.c b/src/nxt_main_process.c
index a5a20d3d..61521854 100644
--- a/src/nxt_main_process.c
+++ b/src/nxt_main_process.c
@@ -950,9 +950,11 @@ nxt_main_process_sigchld_handler(nxt_task_t *task, void *obj, void *data)
 
                 if (rt->nprocesses <= 1) {
                     nxt_runtime_quit(task, 0);
+
+                    return;
                 }
 
-                return;
+                continue;
             }
 
             nxt_port_remove_notify_others(task, process);