From 9451df683afe804bec0addc8cdae885d12187667 Mon Sep 17 00:00:00 2001
From: espie <espie@openbsd.org>
Date: Sat, 30 Jan 2021 11:19:01 +0000
Subject: [PATCH] do not print to STDOUT if we're in background, as requested
 by Theo who pointed at ssh code for process group handling. Thanks

---
 usr.sbin/pkg_add/OpenBSD/ProgressMeter.pm     |  8 +++++-
 .../pkg_add/OpenBSD/ProgressMeter/Term.pm     | 19 ++++++++------
 usr.sbin/pkg_add/OpenBSD/State.pm             | 25 +++++++++++++------
 3 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/usr.sbin/pkg_add/OpenBSD/ProgressMeter.pm b/usr.sbin/pkg_add/OpenBSD/ProgressMeter.pm
index 01b755fe9a7..7c09d19972f 100644
--- a/usr.sbin/pkg_add/OpenBSD/ProgressMeter.pm
+++ b/usr.sbin/pkg_add/OpenBSD/ProgressMeter.pm
@@ -1,5 +1,5 @@
 # ex:ts=8 sw=4:
-# $OpenBSD: ProgressMeter.pm,v 1.50 2021/01/30 10:43:43 espie Exp $
+# $OpenBSD: ProgressMeter.pm,v 1.51 2021/01/30 11:19:01 espie Exp $
 #
 # Copyright (c) 2010 Marc Espie <espie@openbsd.org>
 #
@@ -90,6 +90,12 @@ sub handle_continue
 	$self->{continued} = 1;
 }
 
+sub can_output
+{
+	my $self = shift;
+	return $self->{state}->can_output;
+}
+
 # stub class when no actual progressmeter that still prints out.
 package OpenBSD::ProgressMeter::Stub;
 our @ISA = qw(OpenBSD::ProgressMeter);
diff --git a/usr.sbin/pkg_add/OpenBSD/ProgressMeter/Term.pm b/usr.sbin/pkg_add/OpenBSD/ProgressMeter/Term.pm
index eb5150f6bfc..e3ec480bf1e 100644
--- a/usr.sbin/pkg_add/OpenBSD/ProgressMeter/Term.pm
+++ b/usr.sbin/pkg_add/OpenBSD/ProgressMeter/Term.pm
@@ -1,5 +1,5 @@
 # ex:ts=8 sw=4:
-# $OpenBSD: Term.pm,v 1.41 2021/01/30 10:43:43 espie Exp $
+# $OpenBSD: Term.pm,v 1.42 2021/01/30 11:19:01 espie Exp $
 #
 # Copyright (c) 2004-2007 Marc Espie <espie@openbsd.org>
 #
@@ -202,6 +202,7 @@ sub _show
 sub message
 {
 	my ($self, $message) = @_;
+	return unless $self->can_output;
 	if ($self->{cleareol}) {
 		$message .= $self->{cleareol};
 	} elsif ($self->{playfield} > length($message)) {
@@ -218,6 +219,8 @@ sub show
 {
 	my ($self, $current, $total) = @_;
 
+	return unless $self->can_output;
+
 	if ($self->{playfield}) {
 		my $stars = int (($current * $self->{playfield}) / $total + 0.5);
 		my $percent = int (($current * 100)/$total + 0.5);
@@ -244,10 +247,12 @@ sub clear
 {
 	my $self = shift;
 	return unless length($self->{lastdisplay}) > 0;
-	if ($self->{cleareol}) {
-		print "\r", $self->{cleareol};
-	} else {
-		print "\r", ' 'x length($self->{lastdisplay}), "\r";
+	if ($self->can_output) {
+		if ($self->{cleareol}) {
+			print "\r", $self->{cleareol};
+		} else {
+			print "\r", ' 'x length($self->{lastdisplay}), "\r";
+		}
 	}
 	$self->{lastdisplay} = '';
 	delete $self->{stars};
@@ -256,7 +261,7 @@ sub clear
 sub disable
 {
 	my $self = shift;
-	print "\n" if length($self->{lastdisplay}) > 0;
+	print "\n" if length($self->{lastdisplay}) > 0 and $self->can_output;
 
 	bless $self, "OpenBSD::ProgressMeter::Stub";
 }
@@ -267,7 +272,7 @@ sub next
 	$self->clear;
 
 	$todo //= 'ok';
-	print "\r$self->{header}: $todo\n";
+	print "\r$self->{header}: $todo\n" if $self->can_output;
 }
 
 package ProgressSizer;
diff --git a/usr.sbin/pkg_add/OpenBSD/State.pm b/usr.sbin/pkg_add/OpenBSD/State.pm
index 38d3c6f82b9..8750341bfd7 100644
--- a/usr.sbin/pkg_add/OpenBSD/State.pm
+++ b/usr.sbin/pkg_add/OpenBSD/State.pm
@@ -1,5 +1,5 @@
 # ex:ts=8 sw=4:
-# $OpenBSD: State.pm,v 1.66 2021/01/30 10:37:22 espie Exp $
+# $OpenBSD: State.pm,v 1.67 2021/01/30 11:19:01 espie Exp $
 #
 # Copyright (c) 2007-2014 Marc Espie <espie@openbsd.org>
 #
@@ -120,6 +120,9 @@ sub init
 	$self->{subst} = OpenBSD::Subst->new;
 	$self->{repo} = OpenBSD::PackageRepositoryFactory->new($self);
 	$self->{export_level} = 1;
+	$SIG{'CONT'} = sub {
+		$self->handle_continue;
+	}
 }
 
 sub repo
@@ -131,9 +134,18 @@ sub repo
 sub handle_continue
 {
 	my $self = shift;
-	$self->find_window_size(1);
+	$self->find_window_size(1);	# 1 is legacy interface for dpb
+	# invalidate cache so this runs again after continue
+	delete $self->{can_output};
 }
 
+OpenBSD::Auto::cache(can_output,
+	sub {
+		require POSIX;
+		# XXX uses POSIX semantics so fd, we can hardcode stdout ;)
+		return getpgrp() == POSIX::tcgetpgrp(1); 
+	});
+
 sub sync_display
 {
 }
@@ -241,7 +253,7 @@ sub _fhprint
 sub _print
 {
 	my $self = shift;
-	$self->_fhprint(\*STDOUT, @_);
+	$self->_fhprint(\*STDOUT, @_) if $self->can_output;
 }
 
 sub _errprint
@@ -271,13 +283,13 @@ sub fhsay
 sub print
 {
 	my $self = shift;
-	$self->fhprint(\*STDOUT, @_);
+	$self->fhprint(\*STDOUT, @_) if $self->can_output;
 }
 
 sub say
 {
 	my $self = shift;
-	$self->fhsay(\*STDOUT, @_);
+	$self->fhsay(\*STDOUT, @_) if $self->can_output;
 }
 
 sub errprint
@@ -380,9 +392,6 @@ sub find_window_size
 			$self->find_window_size;
 		};
 	}
-	$SIG{'CONT'} = sub {
-		$self->handle_continue;
-	}
 }
 
 OpenBSD::Auto::cache(signer_list,
-- 
2.20.1