[PATCH 3/2 (squash)] t/httpd-unix: fix race in SIGUSR2 test

[Eric Wong <e@yhbt.net>]

We need to stop workers in the old process, check the socket and
ensure $new_pid is ready to receive signals before killing it.
---
 t/httpd-unix.t | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/t/httpd-unix.t b/t/httpd-unix.t
index 939431f4..a0fe1e31 100644
--- a/t/httpd-unix.t
+++ b/t/httpd-unix.t
@@ -127,6 +127,10 @@ SKIP: {
 	is($?, 0, "daemonized process again");
 	check_sock($unix);
 	my $pid = $read_pid->($pid_file);
+
+	# stop worker to ensure check_sock below hits $new_pid
+	kill('TTOU', $pid) or die "TTOU failed: $!";
+
 	kill('USR2', $pid) or die "USR2 failed: $!";
 	delay_until(sub {
 		$pid != (eval { $read_pid->($pid_file) } // $pid)
@@ -136,6 +140,8 @@ SKIP: {
 	my $old_pid = $read_pid->("$pid_file.oldbin");
 	is($old_pid, $pid, '.oldbin pid file written');
 
+	check_sock($unix); # ensures $new_pid is ready to receive signals
+
 	# first, back out of the upgrade
 	kill('QUIT', $new_pid) or die "kill new PID failed: $!";
 	delay_until(sub {