[PATCH] imap: improve IDLE handling at graceful shutdown

[PATCH] imap: improve IDLE handling at graceful shutdown

[Eric Wong]

Since IMAP IDLE users aren't expected to issue any commands, we
can terminate their connections immediately on graceful
shutdown.

Furthermore, we need to drop the inotify FD from the epoll set
to avoid warnings during global destruction.  Embarassingly,
this required fixing wacky test ordering from 2a717d13f10fcdc6
("nntpd+imapd: detect replaced over.sqlite3")
---
 lib/PublicInbox/IMAP.pm      |  4 ++++
 lib/PublicInbox/InboxIdle.pm |  4 ++++
 t/nntpd.t                    | 34 ++++++++++++++++------------------
 3 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/lib/PublicInbox/IMAP.pm b/lib/PublicInbox/IMAP.pm
index 9ae7c60e..d4ef6efe 100644
--- a/lib/PublicInbox/IMAP.pm
+++ b/lib/PublicInbox/IMAP.pm
@@ -1462,6 +1462,10 @@ sub cmd_starttls ($$) {
 # for graceful shutdown in PublicInbox::Daemon:
 sub busy {
 	my ($self, $now) = @_;
+	if (defined($self->{-idle_tag})) {
+		$self->write(\"* BYE server shutting down\r\n");
+		return; # not busy anymore
+	}
 	($self->{rbuf} || $self->{wbuf} || $self->not_idle_long($now));
 }
 
diff --git a/lib/PublicInbox/InboxIdle.pm b/lib/PublicInbox/InboxIdle.pm
index d60d4f23..d0bb43c5 100644
--- a/lib/PublicInbox/InboxIdle.pm
+++ b/lib/PublicInbox/InboxIdle.pm
@@ -79,4 +79,8 @@ sub event_step {
 	warn "$self->{inot}->poll err: $@\n" if $@;
 }
 
+# for graceful shutdown in PublicInbox::Daemon,
+# just ensure the FD gets closed ASAP and subscribers
+sub busy { 0 }
+
 1;
diff --git a/t/nntpd.t b/t/nntpd.t
index d6042d18..b24720eb 100644
--- a/t/nntpd.t
+++ b/t/nntpd.t
@@ -316,23 +316,6 @@ Date: Fri, 02 Oct 1993 00:00:00 +0000
 		my @xap = grep m!Search/Xapian!, @of;
 		is_deeply(\@xap, [], 'Xapian not loaded in nntpd');
 	}
-	{
-		setsockopt($s, IPPROTO_TCP, TCP_NODELAY, 1);
-		syswrite($s, 'HDR List-id 1-');
-		select(undef, undef, undef, 0.15);
-		ok($td->kill, 'killed nntpd');
-		select(undef, undef, undef, 0.15);
-		syswrite($s, "\r\n");
-		$buf = '';
-		do {
-			sysread($s, $buf, 4096, length($buf));
-		} until ($buf =~ /\r\n\z/);
-		my @r = split("\r\n", $buf);
-		like($r[0], qr/^5\d\d /,
-			'got 5xx response for unoptimized HDR');
-		is(scalar @r, 1, 'only one response line');
-	}
-
 	# -compact requires Xapian
 	SKIP: {
 		require_mods('Search::Xapian', 2);
@@ -356,7 +339,22 @@ Date: Fri, 02 Oct 1993 00:00:00 +0000
 		my @of = xqx([$lsof, '-p', $td->{pid}], undef, $noerr);
 		is(scalar(grep(/\(deleted\)/, @of)), 0, 'no deleted files');
 	};
-
+	{
+		setsockopt($s, IPPROTO_TCP, TCP_NODELAY, 1);
+		syswrite($s, 'HDR List-id 1-');
+		select(undef, undef, undef, 0.15);
+		ok($td->kill, 'killed nntpd');
+		select(undef, undef, undef, 0.15);
+		syswrite($s, "\r\n");
+		$buf = '';
+		do {
+			sysread($s, $buf, 4096, length($buf));
+		} until ($buf =~ /\r\n\z/);
+		my @r = split("\r\n", $buf);
+		like($r[0], qr/^5\d\d /,
+			'got 5xx response for unoptimized HDR');
+		is(scalar @r, 1, 'only one response line');
+	}
 	$n = $s = undef;
 	$td->join;
 	is($?, 0, 'no error in exited process');