1 files changed, 34 insertions, 22 deletions

diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index ceba16e4..b915bb0c 100644
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -12,7 +12,7 @@ use parent qw(PublicInbox::DS PublicInbox::LeiExternal
         PublicInbox::LeiQuery);
 use Getopt::Long ();
 use Socket qw(AF_UNIX SOCK_SEQPACKET MSG_EOR pack_sockaddr_un);
-use Errno qw(EAGAIN EINTR ECONNREFUSED ENOENT ECONNRESET);
+use Errno qw(EPIPE EAGAIN EINTR ECONNREFUSED ENOENT ECONNRESET);
 use Cwd qw(getcwd);
 use POSIX ();
 use IO::Handle ();
@@ -277,7 +277,11 @@ sub x_it ($$) {
         dump_and_clear_log();
         if (my $sock = $self->{sock}) {
                 send($sock, "x_it $code", MSG_EOR);
-        } elsif (!($code & 127)) { # oneshot, ignore signals
+        } elsif (my $signum = ($code & 127)) { # oneshot, usually SIGPIPE (13)
+                $SIG{PIPE} = 'DEFAULT'; # $SIG{$signum} doesn't work
+                kill $signum, $$;
+                sleep; # wait for signal
+        } else { # oneshot
                 # don't want to end up using $? from child processes
                 for my $f (qw(lxs l2m)) {
                         my $wq = delete $self->{$f} or next;
@@ -287,14 +291,15 @@ sub x_it ($$) {
         }
 }
 
-sub puts ($;@) { print { shift->{1} } map { "$_\n" } @_ }
-
-sub out ($;@) { print { shift->{1} } @_ }
-
 sub err ($;@) {
         my $self = shift;
-        my $err = $self->{2} // ($self->{pgr} // [])->[2] // *STDERR{IO};
-        print $err @_, (substr($_[-1], -1, 1) eq "\n" ? () : "\n");
+        my $err = $self->{2} // ($self->{pgr} // [])->[2] // *STDERR{GLOB};
+        my $eor = (substr($_[-1], -1, 1) eq "\n" ? () : "\n");
+        print $err @_, $eor and return;
+        my $old_err = delete $self->{2};
+        close($old_err) if $! == EPIPE && $old_err;;
+        $err = $self->{2} = ($self->{pgr} // [])->[2] // *STDERR{GLOB};
+        print $err @_, $eor or print STDERR @_, $eor;
 }
 
 sub qerr ($;@) { $_[0]->{opt}->{quiet} or err(shift, @_) }
@@ -306,6 +311,17 @@ sub fail ($$;$) {
         undef;
 }
 
+sub out ($;@) {
+        my $self = shift;
+        return if print { $self->{1} // return } @_; # likely
+        return note_sigpipe($self, 1) if $! == EPIPE;
+        my $err = "error writing to stdout: $!";
+        delete $self->{1};
+        fail($self, $err);
+}
+
+sub puts ($;@) { out(shift, map { "$_\n" } @_) }
+
 sub child_error { # passes non-fatal curl exit codes to user
         my ($self, $child_error) = @_; # child_error is $?
         if (my $sock = $self->{sock}) { # send to lei(1) client
@@ -350,27 +366,23 @@ sub io_restore ($$) {
         }
 }
 
-# usage: my %sig = $lei->atfork_child_wq($wq);
-#         local @SIG{keys %sig} = values %sig;
+# triggers sigpipe_handler
+sub note_sigpipe {
+        my ($self, $fd) = @_;
+        close(delete($self->{$fd})); # explicit close silences Perl warning
+        syswrite($self->{op_pipe}, '!') if $self->{op_pipe};
+        x_it($self, 13);
+}
+
 sub atfork_child_wq {
         my ($self, $wq) = @_;
         io_restore($self, $wq);
+        -p $self->{op_pipe} or die 'BUG: {op_pipe} expected';
         io_restore($self->{l2m}, $wq);
         %PATH2CFG = ();
         undef $errors_log;
         $quit = \&CORE::exit;
-        (PIPE => sub {
-                $self->x_it(13); # SIGPIPE = 13
-                # we need to close explicitly to avoid Perl warning on SIGPIPE
-                for my $i (1, 2) {
-                        next unless $self->{$i} && (-p $self->{$i} || -S _);
-                        close(delete $self->{$i});
-                }
-                # trigger the LeiXSearch $done OpPipe:
-                syswrite($self->{op_pipe}, '!') if $self->{op_pipe};
-                $SIG{PIPE} = 'DEFAULT';
-                die bless(\"$_[0]", 'PublicInbox::SIGPIPE'),
-        });
+        $current_lei = $self; # for SIG{__WARN__}
 }
 
 sub io_extract ($;@) {