gruntmaster-exec

   1 #!/usr/bin/perl
   2 use v5.14;
   3 use strict;
   4 use warnings;
   5
   6 use constant +{
   7         # Accepted
   8         AC => 0,
   9
  10         # Internal server error
  11         ERR => -1,
  12
  13         # All other errors
  14         WA => 1,
  15         NZX => 2,
  16         TLE => 3,
  17         OLE => 4,
  18         DIED => 5,
  19         REJ => 10,
  20 };
  21
  22 use BSD::Resource qw/setrlimit RLIMIT_AS RLIMIT_FSIZE/;
  23 use IPC::Signal qw/sig_name sig_num/;
  24 use sigtrap qw/XFSZ/;
  25
  26 use Getopt::Long;
  27 use POSIX qw//;
  28 use Time::HiRes qw/alarm/;
  29
  30 my (@fds, $timeout, $mlimit, $olimit);
  31 my $close = 1;
  32
  33 GetOptions(
  34         "fd=s"      => \@fds,
  35         "timeout=f" => \$timeout,
  36         "mlimit=i"  => \$mlimit,
  37         "olimit=i"  => \$olimit,
  38         "close!"    => \$close,
  39 );
  40
  41 my $ret = fork // die 'Cannot fork';
  42 if ($ret) {
  43         my $tle;
  44         local $SIG{ALRM} = sub { kill KILL => $ret; $tle = 1};
  45         alarm ($timeout || 5);
  46         waitpid $ret, 0;
  47         alarm 0;
  48         my $sig = $? & 127;
  49         my $signame = sig_name $sig;
  50         exit !say TLE,  "\nTime Limit Exceeded"   if $tle;
  51         exit !say OLE,  "\nOutput Limit Exceeded" if $sig && $signame eq 'XFSZ';
  52         exit !say DIED, "\nCrash (SIG$signame)"   if $sig && $signame ne 'PIPE';
  53         exit !say NZX,  "\nNon-zero exit status: " . ($? >> 8) if $? >> 8;
  54         exit !say AC,   "\nAll OK";
  55 } else {
  56         $^F = 50;
  57         if ($close) {
  58                 POSIX::close $_ for 0 .. $^F;
  59         }
  60         for my $fdstring (@fds) {
  61                 my ($fd, $file) = split ' ', $fdstring, 2;
  62                 open my $fh, $file or die $!;
  63                 my $oldfd = fileno $fh;
  64                 if ($oldfd != $fd) {
  65                         POSIX::dup2 $oldfd, $fd or die $!;
  66                         POSIX::close $oldfd or die $!;
  67                 }
  68         }
  69         %ENV = (ONLINE_JUDGE => 1, PATH => $ENV{PATH}, HOME => $ENV{HOME});
  70         setrlimit RLIMIT_AS, $mlimit, $mlimit or die $! if $mlimit;
  71         setrlimit RLIMIT_FSIZE, $olimit, $olimit or die $! if $olimit;
  72         POSIX::setgid 65534; # Set group id to nogroup
  73         POSIX::setuid 65534; # Set user id to nobody
  74         exec @ARGV;
  75 }
  76
  77 1;
  78 __END__
  79
  80 =encoding utf-8
  81
  82 =head1 NAME
  83
  84 gruntmaster-exec - Gruntmaster 6000 executor
  85
  86 =head1 SYNOPSIS
  87
  88   gruntmaster-exec 20000000 111 echo 'Hello, world!'
  89
  90 =head1 DESCRIPTION
  91
  92 gruntmaster-exec is the script used by gruntmasterd to run programs.
  93
  94 The first argument is the address space limit (in bytes), the second argument is the output limit (also in bytes). The rest of the arguments are the command that should be run and its arguments.
  95
  96 gruntmaster-exec sets the resource limits, cleans the environment (except for PATH and HOME), adds the ONLINE_JUDGE environment variable with value 1, and finally C<exec>s the given command.
  97
  98 =head1 AUTHOR
  99
 100 Marius Gavrilescu E<lt>marius@ieval.roE<gt>
 101
 102 =head1 COPYRIGHT AND LICENSE
 103
 104 Copyright (C) 2014 by Marius Gavrilescu
 105
 106 This program is free software: you can redistribute it and/or modify
 107 it under the terms of the GNU Affero General Public License as published by
 108 the Free Software Foundation, either version 3 of the License, or
 109 (at your option) any later version.