lei: less error-prone FD mapping

Keeping track of non-standard FDs gets tricky, so make it easier
by relying on st_dev/st_ino mapping in the transmitted objects.

We'll keep using numbers for the standard FDs since we need to
be able to easily redirect them in the producer (main daemon)
process for (gzip|bzip2|xz) if writing to a compressed mbox.

1 files changed, 4 insertions, 5 deletions

diff --git a/lib/PublicInbox/LeiOverview.pm b/lib/PublicInbox/LeiOverview.pm
index f9a28138..c67e2747 100644
--- a/lib/PublicInbox/LeiOverview.pm
+++ b/lib/PublicInbox/LeiOverview.pm
@@ -220,14 +220,13 @@ sub ovv_each_smsg_cb { # runs in wq worker usually
                 };
         } elsif ($l2m && $l2m->{-wq_s1}) {
                 my ($lei_ipc, @io) = $lei->atfork_parent_wq($l2m);
-                # n.b. $io[0] = qry_status_wr, $io[1] = mbox|stdout,
-                # $io[4] becomes a notification pipe that triggers EOF
+                # $io[-1] becomes a notification pipe that triggers EOF
                 # in this wq worker when all outstanding ->write_mail
                 # calls are complete
-                die "BUG: \$io[4] $io[4] unexpected" if $io[4];
-                pipe($l2m->{each_smsg_done}, $io[4]) or die "pipe: $!";
-                fcntl($io[4], 1031, 4096) if $^O eq 'linux';
+                pipe($l2m->{each_smsg_done}, $io[$#io + 1]) or die "pipe: $!";
+                fcntl($io[-1], 1031, 4096) if $^O eq 'linux'; # F_SETPIPE_SZ
                 delete @$lei_ipc{qw(l2m opt mset_opt cmd)};
+                $lei_ipc->{each_smsg_not_done} = $#io;
                 my $git = $ibxish->git; # (LeiXSearch|Inbox|ExtSearch)->git
                 $self->{git} = $git;
                 my $git_dir = $git->{git_dir};