update copyrights for 2021

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

diff --git a/lib/PublicInbox/InboxIdle.pm b/lib/PublicInbox/InboxIdle.pm
index f1cbc012f2bc6bb3bfb6420082282e2ea919d97f..4d74b3545902f7882d570da28176d6d9b83e3272 100644 (file)
--- a/lib/PublicInbox/InboxIdle.pm
+++ b/lib/PublicInbox/InboxIdle.pm
@@ -1,4 +1,4 @@
-# Copyright (C) 2020 all contributors <meta@public-inbox.org>
+# Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 
 # fields:
@@ -24,21 +24,35 @@ sub in2_arm ($$) { # PublicInbox::Config::each_inbox callback
        my $dir = $ibx->{inboxdir};
        my $inot = $self->{inot};
        my $cur = $self->{pathmap}->{$dir} //= [];
+       my $lock = "$dir/".($ibx->version >= 2 ? 'inbox.lock' : 'ssoma.lock');
 
        # transfer old subscriptions to the current inbox, cancel the old watch
-       if (my $old_ibx = $cur->[0]) {
+       my $old_ibx = $cur->[0];
+       $cur->[0] = $ibx;
+       if ($old_ibx) {
                $ibx->{unlock_subs} and
                        die "BUG: $dir->{unlock_subs} should not exist";
                $ibx->{unlock_subs} = $old_ibx->{unlock_subs};
+
+               # Linux::Inotify2::Watch::name matches if watches are the
+               # same, no point in replacing a watch of the same name
+               if ($cur->[1]->name eq $lock) {
+                       $self->{on_unlock}->{$lock} = $ibx;
+                       return;
+               }
+               # rare, name changed (v1 inbox converted to v2)
                $cur->[1]->cancel; # Linux::Inotify2::Watch::cancel
        }
-       $cur->[0] = $ibx;
 
-       my $lock = "$dir/".($ibx->version >= 2 ? 'inbox.lock' : 'ssoma.lock');
        if (my $w = $cur->[1] = $inot->watch($lock, $IN_MODIFY)) {
                $self->{on_unlock}->{$w->name} = $ibx;
        } else {
                warn "E: ".ref($inot)."->watch($lock, IN_MODIFY) failed: $!\n";
+               if ($!{ENOSPC} && $^O eq 'linux') {
+                       warn <<"";
+I: consider increasing /proc/sys/fs/inotify/max_user_watches
+
+               }
        }
 
        # TODO: detect deleted packs (and possibly other files)
@@ -49,6 +63,9 @@ sub refresh {
        $pi_cfg->each_inbox(\&in2_arm, $self);
 }
 
+# internal API for ease-of-use
+sub watch_inbox { in2_arm($_[1], $_[0]) };
+
 sub new {
        my ($class, $pi_cfg) = @_;
        my $self = bless {}, $class;
@@ -64,7 +81,7 @@ sub new {
        $self->{inot} = $inot;
        $self->{pathmap} = {}; # inboxdir => [ ibx, watch1, watch2, watch3...]
        $self->{on_unlock} = {}; # lock path => ibx
-       refresh($self, $pi_cfg);
+       refresh($self, $pi_cfg) if $pi_cfg;
        PublicInbox::FakeInotify::poll_once($self) if !$ino_cls;
        $self;
 }
@@ -75,7 +92,8 @@ sub event_step {
                my @events = $self->{inot}->read; # Linux::Inotify2::read
                my $on_unlock = $self->{on_unlock};
                for my $ev (@events) {
-                       if (my $ibx = $on_unlock->{$ev->fullname}) {
+                       my $fn = $ev->fullname // next; # cancelled
+                       if (my $ibx = $on_unlock->{$fn}) {
                                $ibx->on_unlock;
                        }
                }