imap: mailboxes list across listeners

Since IMAP mailbox lists are tied to the PublicInbox::Config
object, we can share them the same way the config object is
shared when an -imapd or -netd instance has multiple listeners.

This ought to reduce memory use and startup time when binding
multiple sockets which share a common config file.

diff --git a/lib/PublicInbox/IMAPD.pm b/lib/PublicInbox/IMAPD.pm
index dd0d2c53905a94012328b2bd3094f0026b9a159a..ba6ad05d5b2a74a4bb7480c20809441a769afc63 100644 (file)
--- a/lib/PublicInbox/IMAPD.pm
+++ b/lib/PublicInbox/IMAPD.pm
@@ -23,7 +23,7 @@ sub new {
        }, $class;
 }
 
-sub imapd_refresh_ibx { # pi_cfg->each_inbox cb
+sub _refresh_ibx { # pi_cfg->each_inbox cb
        my ($ibx, $imapd, $cache, $dummies) = @_;
        my $ngname = $ibx->{newsgroup} // return;
 
@@ -56,27 +56,32 @@ sub imapd_refresh_ibx { # pi_cfg->each_inbox cb
 sub refresh_groups {
        my ($self, $sig) = @_;
        my $pi_cfg = PublicInbox::Config->new;
-       my $mailboxes = $self->{mailboxes} = {};
-       my $cache = eval { $pi_cfg->ALL->misc->nntpd_cache_load } // {};
-       my $dummies = {};
-       $pi_cfg->each_inbox(\&imapd_refresh_ibx, $self, $cache, $dummies);
-       %$dummies = (%$dummies, %$mailboxes);
-       $mailboxes = $self->{mailboxes} = $dummies;
-       @{$self->{mailboxlist}} = map { $_->[2] }
-               sort { $a->[0] cmp $b->[0] || $a->[1] <=> $b->[1] }
-               map {
-                       my $u = $_; # capitalize "INBOX" for user-familiarity
-                       $u =~ s/\Ainbox(\.|\z)/INBOX$1/i;
-                       if ($mailboxes->{$_} == $dummy) {
-                               [ $u, -1,
-                                 qq[* LIST (\\HasChildren) "." $u\r\n]]
-                       } else {
-                               $u =~ /\A(.+)\.([0-9]+)\z/ or
-                                       die "BUG: `$u' has no slice digit(s)";
-                               [ $1, $2 + 0,
-                                 qq[* LIST (\\HasNoChildren) "." $u\r\n] ]
-                       }
-               } keys %$mailboxes;
+       $self->{mailboxes} = $pi_cfg->{-imap_mailboxes} // do {
+               my $mailboxes = $self->{mailboxes} = {};
+               my $cache = eval { $pi_cfg->ALL->misc->nntpd_cache_load } // {};
+               my $dummies = {};
+               $pi_cfg->each_inbox(\&_refresh_ibx, $self, $cache, $dummies);
+               %$mailboxes = (%$dummies, %$mailboxes);
+               @{$pi_cfg->{-imap_mailboxlist}} = map { $_->[2] }
+                       sort { $a->[0] cmp $b->[0] || $a->[1] <=> $b->[1] }
+                       map {
+                               # capitalize "INBOX" for user-familiarity
+                               my $u = $_;
+                               $u =~ s/\Ainbox(\.|\z)/INBOX$1/i;
+                               if ($mailboxes->{$_} == $dummy) {
+                                       [ $u, -1,
+                                         qq[* LIST (\\HasChildren) "." $u\r\n]]
+                               } else {
+                                       $u =~ /\A(.+)\.([0-9]+)\z/ or die
+"BUG: `$u' has no slice digit(s)";
+                                       [ $1, $2 + 0, '* LIST '.
+                                         qq[(\\HasNoChildren) "." $u\r\n] ]
+                               }
+                       } keys %$mailboxes;
+               $pi_cfg->{-imap_mailboxes} = $mailboxes;
+       };
+       $self->{mailboxlist} = $pi_cfg->{-imap_mailboxlist} //
+                       die 'BUG: no mailboxlist';
        $self->{pi_cfg} = $pi_cfg;
        if (my $idler = $self->{idler}) {
                $idler->refresh($pi_cfg);