-#!/usr/bin/perl -w
+#!/usr/bin/perl
use v5.14;
use strict;
+use warnings;
-use BSD::Resource qw/setrlimit RLIMIT_AS RLIMIT_FSIZE/;
-use sigtrap qw/XFSZ/;
-
-##################################################
+use constant +{
+ # Accepted
+ AC => 0,
-my ($mlimit, $olimit, @args) = @ARGV;
+ # Internal server error
+ ERR => -1,
-setrlimit RLIMIT_AS, $mlimit, $mlimit or die $! if $mlimit;
-setrlimit RLIMIT_FSIZE, $olimit, $olimit or die $! if $olimit;
+ # All other errors
+ WA => 1,
+ NZX => 2,
+ TLE => 3,
+ OLE => 4,
+ DIED => 5,
+ REJ => 10,
+};
-%ENV = (ONLINE_JUDGE => 1, PATH => $ENV{PATH}, HOME => $ENV{HOME});
-exec @args;
+use BSD::Resource qw/setrlimit RLIMIT_AS RLIMIT_FSIZE/;
+use IPC::Signal qw/sig_name sig_num/;
+use sigtrap qw/XFSZ/;
+use Getopt::Long;
+use POSIX qw//;
+use Time::HiRes qw/alarm/;
+
+my (@fds, $timeout, $mlimit, $olimit);
+GetOptions(
+ "fd=s" => \@fds,
+ "timeout=f" => \$timeout,
+ "mlimit=i" => \$mlimit,
+ "olimit=i" => \$olimit,
+);
+
+my $ret = fork // die 'Cannot fork';
+if ($ret) {
+ my $tle;
+ local $SIG{ALRM} = sub { kill KILL => $ret; $tle = 1};
+ alarm ($timeout || 5);
+ waitpid $ret, 0;
+ alarm 0;
+ my $sig = $? & 127;
+ my $signame = sig_name $sig;
+ exit !say TLE, "\nTime Limit Exceeded" if $tle;
+ exit !say OLE, "\nOutput Limit Exceeded" if $sig && $signame eq 'XFSZ';
+ exit !say DIED, "\nCrash (SIG$signame)" if $sig && $signame ne 'PIPE';
+ exit !say NZX, "\nNon-zero exit status: " . ($? >> 8) if $? >> 8;
+ exit !say AC, "\nAll OK";
+} else {
+ $^F = 50;
+ POSIX::close $_ for 0 .. $^F;
+ for my $fdstring (@fds) {
+ my ($fd, $file) = split ' ', $fdstring, 2;
+ open my $fh, $file or die $!;
+ my $oldfd = fileno $fh;
+ if ($oldfd != $fd) {
+ POSIX::dup2 $oldfd, $fd or die $!;
+ POSIX::close $oldfd or die $!;
+ }
+ }
+ %ENV = (ONLINE_JUDGE => 1, PATH => $ENV{PATH}, HOME => $ENV{HOME});
+ setrlimit RLIMIT_AS, $mlimit, $mlimit or die $! if $mlimit;
+ setrlimit RLIMIT_FSIZE, $olimit, $olimit or die $! if $olimit;
+ POSIX::setgid 65534; # Set group id to nogroup
+ POSIX::setuid 65534; # Set user id to nobody
+ exec @ARGV;
+}
+
+1;
__END__
=encoding utf-8