[PATCH 11/22] ipc: DESTROY and wq_workers methods

[Eric Wong <e@80x24.org>]

We'll enable automatic cleanup when IPC classes go out-of-scope
to avoid leaving zombies around.

->wq_workers will be a useful convenience method to change
worker counts.
---
 lib/PublicInbox/IPC.pm | 23 +++++++++++++++++++++--
 t/ipc.t                | 10 +++++++---
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/lib/PublicInbox/IPC.pm b/lib/PublicInbox/IPC.pm
index 4d29532c..8a3120c9 100644
--- a/lib/PublicInbox/IPC.pm
+++ b/lib/PublicInbox/IPC.pm
@@ -276,7 +276,7 @@ sub _wq_worker_start ($$) {
 	if ($pid == 0) {
 		eval { PublicInbox::DS->Reset };
 		close(delete $self->{-wq_s1});
-		delete $self->{qw(-wq_workers -wq_quit)};
+		delete $self->{qw(-wq_workers -wq_quit -wq_ppid)};
 		my $quit = sub { $self->{-wq_quit} = 1 };
 		$SIG{$_} = $quit for (qw(TERM INT QUIT));
 		$SIG{$_} = 'IGNORE' for (qw(TTOU TTIN));
@@ -347,10 +347,24 @@ sub wq_worker_decr_wait {
 	dwaitpid($pid, \&ipc_worker_reap, $self);
 }
 
+# set or retrieve number of workers
+sub wq_workers {
+	my ($self, $nr) = @_;
+	my $cur = $self->{-wq_workers} or return;
+	if (defined $nr) {
+		while (scalar(keys(%$cur)) > $nr) {
+			$self->wq_worker_decr;
+			$self->wq_worker_decr_wait;
+		}
+		$self->wq_worker_incr while scalar(keys(%$cur)) < $nr;
+	}
+	scalar(keys(%$cur));
+}
+
 sub wq_close {
 	my ($self) = @_;
 	delete @$self{qw(-wq_s1 -wq_s2)} or return;
-	my $ppid = delete $self->{-wq_ppid} // die 'BUG: no wq_ppid';
+	my $ppid = delete $self->{-wq_ppid} or return;
 	my $workers = delete $self->{-wq_workers} // die 'BUG: no wq_workers';
 	return if $ppid != $$; # can't reap siblings or parents
 	for my $pid (keys %$workers) {
@@ -358,4 +372,9 @@ sub wq_close {
 	}
 }
 
+sub DESTROY {
+	wq_close($_[0]);
+	ipc_worker_stop($_[0]);
+}
+
 1;
diff --git a/t/ipc.t b/t/ipc.t
index 51e347c6..903294c5 100644
--- a/t/ipc.t
+++ b/t/ipc.t
@@ -170,11 +170,15 @@ is($warn[2], $warn[1], 'worker did not die');
 
 $SIG{__WARN__} = 'DEFAULT';
 is($ipc->wq_workers_start('wq', 1), $$, 'workers started again');
-is(scalar(keys %{$ipc->{-wq_workers}}), 1, '1 worker started');
+is($ipc->wq_workers, 1, '1 worker started');
 $ipc->wq_worker_incr;
-is(scalar(keys %{$ipc->{-wq_workers}}), 2, 'worker count bumped');
+is($ipc->wq_workers, 2, 'worker count bumped');
 $ipc->wq_worker_decr;
 $ipc->wq_worker_decr_wait(10);
-is(scalar(keys %{$ipc->{-wq_workers}}), 1, 'worker count lowered');
+is($ipc->wq_workers, 1, 'worker count lowered');
+is($ipc->wq_workers(2), 2, 'worker count set');
+is($ipc->wq_workers, 2, 'worker count stayed set');
+$ipc->wq_close;
+is($ipc->wq_workers, undef, 'workers undef after close');
 
 done_testing;