inboxidle: new class to detect inbox changes

[public-inbox.git] / lib / PublicInbox / InboxIdle.pm

diff --git a/lib/PublicInbox/InboxIdle.pm b/lib/PublicInbox/InboxIdle.pm
new file mode 100644 (file)
index 0000000..095a801
--- /dev/null
+++ b/lib/PublicInbox/InboxIdle.pm
@@ -0,0 +1,55 @@
+# Copyright (C) 2020 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+
+package PublicInbox::InboxIdle;
+use strict;
+use base qw(PublicInbox::DS);
+use fields qw(pi_config inot);
+use Symbol qw(gensym);
+use PublicInbox::Syscall qw(EPOLLIN EPOLLET);
+my $IN_CLOSE = 0x08 | 0x10; # match Linux inotify
+my $ino_cls;
+if ($^O eq 'linux' && eval { require Linux::Inotify2; 1 }) {
+       $IN_CLOSE = Linux::Inotify2::IN_CLOSE();
+       $ino_cls = 'Linux::Inotify2';
+} elsif (eval { require PublicInbox::KQNotify }) {
+       $IN_CLOSE = PublicInbox::KQNotify::IN_CLOSE();
+       $ino_cls = 'PublicInbox::KQNotify';
+}
+require PublicInbox::In2Tie if $ino_cls;
+
+sub in2_arm ($$) { # PublicInbox::Config::each_inbox callback
+       my ($ibx, $inot) = @_;
+       my $path = "$ibx->{inboxdir}/";
+       $path .= $ibx->version >= 2 ? 'inbox.lock' : 'ssoma.lock';
+       $inot->watch($path, $IN_CLOSE, sub { $ibx->on_unlock });
+       # TODO: detect deleted packs (and possibly other files)
+}
+
+sub new {
+       my ($class, $pi_config) = @_;
+       my $self = fields::new($class);
+       my $inot;
+       if ($ino_cls) {
+               $inot = $ino_cls->new or die "E: $ino_cls->new: $!";
+               my $sock = gensym;
+               tie *$sock, 'PublicInbox::In2Tie', $inot;
+               $inot->blocking(0);
+               $inot->on_overflow(undef); # broadcasts everything on overflow
+               $self->SUPER::new($sock, EPOLLIN | EPOLLET);
+       } else {
+               require PublicInbox::FakeInotify;
+               $inot = PublicInbox::FakeInotify->new;
+       }
+       $self->{inot} = $inot;
+       $pi_config->each_inbox(\&in2_arm, $inot);
+       $self;
+}
+
+sub event_step {
+       my ($self) = @_;
+       eval { $self->{inot}->poll }; # Linux::Inotify2::poll
+       warn "$self->{inot}->poll err: $@\n" if $@;
+}
+
+1;