lei/store: use SOCK_SEQPACKET rather than pipe

This has several advantages:

* no need to use ipc.lock to protect a pipe for non-atomic writes

* ability to pass FDs.  In another commit, this will let us
  simplify lei->sto_done_request and pass newly-created
  sockets to lei/store directly.

disadvantages:

- an extra pipe is required for rare messages over several
  hundred KB, this is probably a non-issue, though

The performance delta is unknown, but I expect shards
(which remain pipes) to be the primary bottleneck IPC-wise
for lei/store.

1 files changed, 12 insertions, 10 deletions

diff --git a/lib/PublicInbox/LeiToMail.pm b/lib/PublicInbox/LeiToMail.pm
index 9f7171fb..a419b83f 100644
--- a/lib/PublicInbox/LeiToMail.pm
+++ b/lib/PublicInbox/LeiToMail.pm
@@ -215,14 +215,14 @@ sub update_kw_maybe ($$$$) {
         my $c = $lse->kw_changed($eml, $kw, my $docids = []);
         my $vmd = { kw => $kw };
         if (scalar @$docids) { # already in lei/store
-                $lei->{sto}->ipc_do('set_eml_vmd', undef, $vmd, $docids) if $c;
+                $lei->{sto}->wq_do('set_eml_vmd', undef, $vmd, $docids) if $c;
         } elsif (my $xoids = $lei->{ale}->xoids_for($eml)) {
                 # it's in an external, only set kw, here
-                $lei->{sto}->ipc_do('set_xvmd', $xoids, $eml, $vmd);
+                $lei->{sto}->wq_do('set_xvmd', $xoids, $eml, $vmd);
         } else { # never-before-seen, import the whole thing
                 # XXX this is critical in protecting against accidental
                 # data loss without --augment
-                $lei->{sto}->ipc_do('set_eml', $eml, $vmd);
+                $lei->{sto}->wq_do('set_eml', $eml, $vmd);
         }
 }
 
@@ -296,7 +296,7 @@ sub _maildir_write_cb ($$) {
                 $lse->xsmsg_vmd($smsg) if $lse;
                 my $n = _buf2maildir($dst, $bref // \($eml->as_string),
                                         $smsg, $dir);
-                $sto->ipc_do('set_sync_info', $smsg->{blob}, $out, $n) if $sto;
+                $sto->wq_do('set_sync_info', $smsg->{blob}, $out, $n) if $sto;
                 ++$lei->{-nr_write};
         }
 }
@@ -326,7 +326,7 @@ sub _imap_write_cb ($$) {
                 }
                 # imap_append returns UID if IMAP server has UIDPLUS extension
                 ($sto && $uid =~ /\A[0-9]+\z/) and
-                        $sto->ipc_do('set_sync_info',
+                        $sto->wq_do('set_sync_info',
                                         $smsg->{blob}, $$uri, $uid + 0);
                 ++$lei->{-nr_write};
         }
@@ -360,7 +360,7 @@ sub _v2_write_cb ($$) {
                 my ($bref, $smsg, $eml) = @_;
                 $eml //= PublicInbox::Eml->new($bref);
                 return if $dedupe && $dedupe->is_dup($eml, $smsg);
-                $lei->{v2w}->ipc_do('add', $eml); # V2Writable->add
+                $lei->{v2w}->wq_do('add', $eml); # V2Writable->add
                 ++$lei->{-nr_write};
         }
 }
@@ -658,9 +658,10 @@ sub _pre_augment_v2 {
         }
         PublicInbox::InboxWritable->new($ibx, @creat);
         $ibx->init_inbox if @creat;
-        my $v2w = $lei->{v2w} = $ibx->importer;
-        $v2w->ipc_lock_init("$dir/ipc.lock");
-        $v2w->ipc_worker_spawn("lei/v2w $dir", $lei->oldset, { lei => $lei });
+        my $v2w = $ibx->importer;
+        $v2w->{-wq_no_bcast} = 1;
+        $v2w->wq_workers_start("lei/v2w $dir", 1, $lei->oldset, {lei => $lei});
+        $lei->{v2w} = $v2w;
         return if !$lei->{opt}->{shared};
         my $d = "$lei->{ale}->{git}->{git_dir}/objects";
         my $al = "$dir/git/0.git/objects/info/alternates";
@@ -689,7 +690,7 @@ sub do_augment { # slow, runs in wq worker
 sub post_augment {
         my ($self, $lei, @args) = @_;
         my $wait = $lei->{opt}->{'import-before'} ?
-                        $lei->{sto}->ipc_do('checkpoint', 1) : 0;
+                        $lei->{sto}->wq_do('checkpoint', 1) : 0;
         # _post_augment_mbox
         my $m = $self->can("_post_augment_$self->{base_type}") or return;
         $m->($self, $lei, @args);
@@ -774,6 +775,7 @@ sub write_mail { # via ->wq_io_do
 
 sub wq_atexit_child {
         my ($self) = @_;
+        local $PublicInbox::DS::in_loop = 0; # waitpid synchronously
         my $lei = $self->{lei};
         delete $self->{wcb};
         $lei->{ale}->git->async_wait_all;