[PATCH 12/19] lei: more consistent IPC exit and error handling

[Eric Wong <e@80x24.org>]

We're able to propagate $? from wq_workers in a consistent
manner, now.
---
 lib/PublicInbox/IPC.pm        | 22 +++++++++++-----------
 lib/PublicInbox/LEI.pm        |  6 +++---
 lib/PublicInbox/LeiImport.pm  | 14 ++++++++++----
 lib/PublicInbox/LeiXSearch.pm | 12 +++++++++---
 4 files changed, 33 insertions(+), 21 deletions(-)

diff --git a/lib/PublicInbox/IPC.pm b/lib/PublicInbox/IPC.pm
index 728f726c..c8673e26 100644
--- a/lib/PublicInbox/IPC.pm
+++ b/lib/PublicInbox/IPC.pm
@@ -140,10 +140,9 @@ sub ipc_worker_reap { # dwaitpid callback
 }
 
 sub wq_wait_old {
-	my ($self, @args) = @_;
-	my $cb = ref($args[0]) eq 'CODE' ? shift(@args) : \&ipc_worker_reap;
+	my ($self, $cb, @args) = @_;
 	my $pids = delete $self->{"-wq_old_pids.$$"} or return;
-	dwaitpid($_, $cb, [$self, @args]) for @$pids;
+	dwaitpid($_, $cb // \&ipc_worker_reap, [$self, @args]) for @$pids;
 }
 
 # for base class, override in sub classes
@@ -348,13 +347,12 @@ sub wq_exit { # wakes up wq_worker_decr_wait
 sub wq_worker_decr { # SIGTTOU handler, kills first idle worker
 	my ($self) = @_;
 	return unless wq_workers($self);
-	my $s2 = $self->{-wq_s2} // die 'BUG: no wq_s2';
-	$self->wq_io_do('wq_exit', [ $s2, $s2, $s2 ]);
+	$self->wq_io_do('wq_exit');
 	# caller must call wq_worker_decr_wait in main loop
 }
 
 sub wq_worker_decr_wait {
-	my ($self, $timeout) = @_;
+	my ($self, $timeout, $cb, @args) = @_;
 	return if $self->{-wq_ppid} != $$; # can't reap siblings or parents
 	my $s1 = $self->{-wq_s1} // croak 'BUG: no wq_s1';
 	vec(my $rin = '', fileno($s1), 1) = 1;
@@ -363,17 +361,17 @@ sub wq_worker_decr_wait {
 	recv($s1, my $pid, 64, 0) // croak "recv: $!";
 	my $workers = $self->{-wq_workers} // croak 'BUG: no wq_workers';
 	delete $workers->{$pid} // croak "BUG: PID:$pid invalid";
-	dwaitpid($pid, \&ipc_worker_reap, $self);
+	dwaitpid($pid, $cb // \&ipc_worker_reap, [ $self, @args ]);
 }
 
 # set or retrieve number of workers
 sub wq_workers {
-	my ($self, $nr) = @_;
+	my ($self, $nr, $cb, @args) = @_;
 	my $cur = $self->{-wq_workers} or return;
 	if (defined $nr) {
 		while (scalar(keys(%$cur)) > $nr) {
 			$self->wq_worker_decr;
-			$self->wq_worker_decr_wait;
+			$self->wq_worker_decr_wait(undef, $cb, @args);
 		}
 		$self->wq_worker_incr while scalar(keys(%$cur)) < $nr;
 	}
@@ -381,7 +379,7 @@ sub wq_workers {
 }
 
 sub wq_close {
-	my ($self, $nohang) = @_;
+	my ($self, $nohang, $cb, @args) = @_;
 	delete @$self{qw(-wq_s1 -wq_s2)} or return;
 	my $ppid = delete $self->{-wq_ppid} or return;
 	my $workers = delete $self->{-wq_workers} // die 'BUG: no wq_workers';
@@ -390,7 +388,9 @@ sub wq_close {
 	if ($nohang) {
 		push @{$self->{"-wq_old_pids.$$"}}, @pids;
 	} else {
-		dwaitpid($_, \&ipc_worker_reap, $self) for @pids;
+		$cb //= \&ipc_worker_reap;
+		unshift @args, $self;
+		dwaitpid($_, $cb, \@args) for @pids;
 	}
 }
 
diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index 515bc2a3..21862488 100644
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -360,7 +360,7 @@ sub fail_handler ($;$$) {
 	my ($lei, $code, $io) = @_;
 	for my $f (@WQ_KEYS) {
 		my $wq = delete $lei->{$f} or next;
-		$wq->wq_wait_old($lei) if $wq->wq_kill_old; # lei-daemon
+		$wq->wq_wait_old(undef, $lei) if $wq->wq_kill_old; # lei-daemon
 	}
 	close($io) if $io; # needed to avoid warnings on SIGPIPE
 	$lei->x_it($code // (1 >> 8));
@@ -827,9 +827,9 @@ sub dclose {
 	for my $f (@WQ_KEYS) {
 		my $wq = delete $self->{$f} or next;
 		if ($wq->wq_kill) {
-			$wq->wq_close
+			$wq->wq_close(0, undef, $self);
 		} elsif ($wq->wq_kill_old) {
-			$wq->wq_wait_old($self);
+			$wq->wq_wait_old(undef, $self);
 		}
 	}
 	close(delete $self->{1}) if $self->{1}; # may reap_compress
diff --git a/lib/PublicInbox/LeiImport.pm b/lib/PublicInbox/LeiImport.pm
index 3a99570e..2b2dc2f7 100644
--- a/lib/PublicInbox/LeiImport.pm
+++ b/lib/PublicInbox/LeiImport.pm
@@ -14,12 +14,18 @@ sub _import_eml { # MboxReader callback
 	$sto->ipc_do('set_eml', $eml, $set_kw ? $sto->mbox_keywords($eml) : ());
 }
 
+sub import_done_wait { # dwaitpid callback
+	my ($arg, $pid) = @_;
+	my ($imp, $lei) = @$arg;
+	$lei->child_error($?, 'non-fatal errors during import') if $?;
+	my $ign = $lei->{sto}->ipc_do('done'); # PublicInbox::LeiStore::done
+	$lei->dclose;
+}
+
 sub import_done { # EOF callback for main daemon
 	my ($lei) = @_;
-	my $imp = delete $lei->{imp};
-	$imp->wq_wait_old($lei) if $imp;
-	my $wait = $lei->{sto}->ipc_do('done');
-	$lei->dclose;
+	my $imp = delete $lei->{imp} or return;
+	$imp->wq_wait_old(\&import_done_wait, $lei);
 }
 
 sub call { # the main "lei import" method
diff --git a/lib/PublicInbox/LeiXSearch.pm b/lib/PublicInbox/LeiXSearch.pm
index 1ba767c1..1024b020 100644
--- a/lib/PublicInbox/LeiXSearch.pm
+++ b/lib/PublicInbox/LeiXSearch.pm
@@ -279,12 +279,18 @@ sub git_tmp ($) {
 	$git;
 }
 
+sub xsearch_done_wait { # dwaitpid callback
+	my ($arg, $pid) = @_;
+	my ($wq, $lei) = @$arg;
+	$lei->child_error($?, 'non-fatal error from '.ref($wq)) if $?;
+}
+
 sub query_done { # EOF callback for main daemon
 	my ($lei) = @_;
 	my $l2m = delete $lei->{l2m};
-	$l2m->wq_wait_old($lei) if $l2m;
+	$l2m->wq_wait_old(\&xsearch_done_wait, $lei) if $l2m;
 	if (my $lxs = delete $lei->{lxs}) {
-		$lxs->wq_wait_old($lei);
+		$lxs->wq_wait_old(\&xsearch_done_wait, $lei);
 	}
 	$lei->{ovv}->ovv_end($lei);
 	if ($l2m) { # close() calls LeiToMail reap_compress
@@ -309,7 +315,7 @@ sub do_post_augment {
 	if (my $err = $@) {
 		if (my $lxs = delete $lei->{lxs}) {
 			$lxs->wq_kill;
-			$lxs->wq_close;
+			$lxs->wq_close(0, undef, $lei);
 		}
 		$lei->fail("$err");
 	}