[PATCH 10/30] qspawn: psgi_return_start: hoist out from psgi_return

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

Instead of just passing the rpipe to the start_cb, pass the
entire qspawn ref to start_cb.  Update existing callers to
avoid circular refs.
---
 lib/PublicInbox/Qspawn.pm | 41 ++++++++++++++++++++-------------------
 t/qspawn.t                | 19 +++++++++---------
 2 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/lib/PublicInbox/Qspawn.pm b/lib/PublicInbox/Qspawn.pm
index 0967bcfa..33e20147 100644
--- a/lib/PublicInbox/Qspawn.pm
+++ b/lib/PublicInbox/Qspawn.pm
@@ -66,7 +66,7 @@ sub _do_spawn {
 	} else {
 		$self->{err} = $!;
 	}
-	$start_cb->($self->{rpipe});
+	$start_cb->($self);
 }
 
 sub child_err ($) {
@@ -140,7 +140,7 @@ sub finish ($) {
 	}
 }
 
-sub start {
+sub start ($$$) {
 	my ($self, $limiter, $start_cb) = @_;
 	if ($limiter->{running} < $limiter->{max}) {
 		_do_spawn($self, $start_cb, $limiter);
@@ -275,6 +275,17 @@ sub psgi_return_init_cb {
 	$wcb = undef;
 }
 
+sub psgi_return_start { # may run later, much later...
+	my ($self) = @_;
+	if (my $async = $self->{psgi_env}->{'pi-httpd.async'}) {
+		# PublicInbox::HTTPD::Async->new(rpipe, $cb, $cb_arg, $end_obj)
+		$self->{async} = $async->($self->{rpipe},
+					\&psgi_return_init_cb, $self, $self);
+	} else { # generic PSGI
+		psgi_return_init_cb($self) while $self->{parse_hdr};
+	}
+}
+
 # Used for streaming the stdout of one process as a PSGI response.
 #
 # $env is the PSGI env.
@@ -303,30 +314,20 @@ sub psgi_return {
 	$self->{hdr_buf} = \(my $hdr_buf = '');
 	$self->{parse_hdr} = $parse_hdr;
 	$limiter ||= $def_limiter ||= PublicInbox::Qspawn::Limiter->new(32);
-	my $start_cb = sub { # may run later, much later...
-		if (my $async = $env->{'pi-httpd.async'}) {
-			# PublicInbox::HTTPD::Async->new(rpipe, $cb, $cb_arg,
-			#				 $end_obj)
-			$self->{async} = $async->($self->{rpipe},
-						\&psgi_return_init_cb, $self,
-						$self);
-		} else { # generic PSGI
-			psgi_return_init_cb($self) while $self->{parse_hdr};
-		}
-	};
 
 	# the caller already captured the PSGI write callback from
 	# the PSGI server, so we can call ->start, here:
-	return $self->start($limiter, $start_cb) if $env->{'qspawn.wcb'};
+	$env->{'qspawn.wcb'} and
+		return start($self, $limiter, \&psgi_return_start);
 
 	# the caller will return this sub to the PSGI server, so
-	# it can set the response callback (that is, for PublicInbox::HTTP,
-	# the chunked_wcb or identity_wcb callback), but other HTTP servers
-	# are supported:
+	# it can set the response callback (that is, for
+	# PublicInbox::HTTP, the chunked_wcb or identity_wcb callback),
+	# but other HTTP servers are supported:
 	sub {
-		$self->{psgi_env}->{'qspawn.wcb'} = $_[0];
-		$self->start($limiter, $start_cb);
-	};
+		$env->{'qspawn.wcb'} = $_[0];
+		start($self, $limiter, \&psgi_return_start);
+	}
 }
 
 package PublicInbox::Qspawn::Limiter;
diff --git a/t/qspawn.t b/t/qspawn.t
index fc288a2d..8bc88e0e 100644
--- a/t/qspawn.t
+++ b/t/qspawn.t
@@ -23,9 +23,9 @@ my $limiter = PublicInbox::Qspawn::Limiter->new(1);
 	my $x = PublicInbox::Qspawn->new([qw(true)]);
 	my $run = 0;
 	$x->start($limiter, sub {
-		my ($rpipe) = @_;
-		is(0, sysread($rpipe, my $buf, 1), 'read zero bytes');
-		ok(!finish_err($x), 'no error on finish');
+		my ($self) = @_;
+		is(0, sysread($self->{rpipe}, my $buf, 1), 'read zero bytes');
+		ok(!finish_err($self), 'no error on finish');
 		$run = 1;
 	});
 	is($run, 1, 'callback ran alright');
@@ -35,9 +35,10 @@ my $limiter = PublicInbox::Qspawn::Limiter->new(1);
 	my $x = PublicInbox::Qspawn->new([qw(false)]);
 	my $run = 0;
 	$x->start($limiter, sub {
-		my ($rpipe) = @_;
-		is(0, sysread($rpipe, my $buf, 1), 'read zero bytes from false');
-		ok(finish_err($x), 'error on finish');
+		my ($self) = @_;
+		is(0, sysread($self->{rpipe}, my $buf, 1),
+				'read zero bytes from false');
+		ok(finish_err($self), 'error on finish');
 		$run = 1;
 	});
 	is($run, 1, 'callback ran alright');
@@ -47,16 +48,16 @@ foreach my $cmd ([qw(sleep 1)], [qw(sh -c), 'sleep 1; false']) {
 	my $s = PublicInbox::Qspawn->new($cmd);
 	my @run;
 	$s->start($limiter, sub {
-		my ($rpipe) = @_;
+		my ($self) = @_;
 		push @run, 'sleep';
-		is(0, sysread($rpipe, my $buf, 1), 'read zero bytes');
+		is(0, sysread($self->{rpipe}, my $buf, 1), 'read zero bytes');
 	});
 	my $n = 0;
 	my @t = map {
 		my $i = $n++;
 		my $x = PublicInbox::Qspawn->new([qw(true)]);
 		$x->start($limiter, sub {
-			my ($rpipe) = @_;
+			my ($self) = @_;
 			push @run, $i;
 		});
 		[$x, $i]