[PATCH 02/11] t/check-www-inbox: replace IPC::Run with PublicInbox::Spawn

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

Because WWW::Mechanize uses truckload of memory, fork
needs to prepare all that memory for CoW, which ends up
bailing with ENOMEM.
---
 t/check-www-inbox.perl | 39 ++++++++++++++++++++++++++++++++++-----
 1 file changed, 34 insertions(+), 5 deletions(-)

diff --git a/t/check-www-inbox.perl b/t/check-www-inbox.perl
index 1e88e95..933362a 100644
--- a/t/check-www-inbox.perl
+++ b/t/check-www-inbox.perl
@@ -14,6 +14,12 @@ use POSIX qw(:sys_wait_h);
 use Time::HiRes qw(gettimeofday tv_interval);
 use WWW::Mechanize;
 use Data::Dumper;
+
+# we want to use vfork+exec with spawn, WWW::Mechanize can use too much
+# memory and fork(2) fails
+use PublicInbox::Spawn qw(spawn which);
+$ENV{PERL_INLINE_DIRECTORY} or warn "PERL_INLINE_DIRECTORY unset, may OOM\n";
+
 our $tmp_owner = $$;
 my $nproc = 4;
 my $slow = 0.5;
@@ -24,13 +30,35 @@ my %opts = (
 GetOptions(%opts) or die "bad command-line args\n$usage";
 my $root_url = shift or die $usage;
 
-chomp(my $xmlstarlet = `which xmlstarlet 2>/dev/null`);
+chomp(my $xmlstarlet = which('xmlstarlet'));
 my $atom_check = eval {
-	require IPC::Run;
 	my $cmd = [ qw(xmlstarlet val -e -) ];
 	sub {
 		my ($in, $out, $err) = @_;
-		IPC::Run::run($cmd, $in, $out, $err);
+		use autodie;
+		open my $in_fh, '+>', undef;
+		open my $out_fh, '+>', undef;
+		open my $err_fh, '+>', undef;
+		print $in_fh $$in;
+		$in_fh->flush;
+		sysseek($in_fh, 0, 0);
+		my $rdr = {
+			0 => fileno($in_fh),
+			1 => fileno($out_fh),
+			2 => fileno($err_fh),
+		};
+		my $pid = spawn($cmd, undef, $rdr);
+		defined $pid or die "spawn failure: $!";
+		while (waitpid($pid, 0) != $pid) {
+			next if $!{EINTR};
+			warn "waitpid(xmlstarlet, $pid) $!";
+			return $!;
+		}
+		sysseek($out_fh, 0, 0);
+		sysread($out_fh, $$out, -s $out_fh);
+		sysseek($err_fh, 0, 0);
+		sysread($err_fh, $$err, -s $err_fh);
+		$?
 	}
 } if $xmlstarlet;
 
@@ -120,6 +148,7 @@ while (keys %workers) { # reacts to SIGCHLD
 
 sub worker_loop {
 	my ($todo_rd, $done_wr) = @_;
+	$SIG{CHLD} = 'DEFAULT';
 	my $m = WWW::Mechanize->new(autocheck => 0);
 	my $cc = LWP::ConnCache->new;
 	$m->conn_cache($cc);
@@ -164,8 +193,8 @@ sub worker_loop {
 		if ($atom_check && $ct =~ m!\bapplication/atom\+xml\b!) {
 			my $raw = $r->decoded_content;
 			my ($out, $err) = ('', '');
-			$atom_check->(\$raw, \$out, \$err) and
-				warn "Atom ($?) - $u - <1:$out> <2:$err>\n";
+			my $fail = $atom_check->(\$raw, \$out, \$err);
+			warn "Atom ($fail) - $u - <1:$out> <2:$err>\n" if $fail;
 		}
 
 		next if $ct !~ m!\btext/html\b!;
-- 
EW