compiler_vm: add ulimits; fix print_last_statement()

applets/compiler_vm/guest/bin/guest-gdb

@@ -350,7 +350,7 @@ sub dispatch_user_command($context, $command) {
         'dump'   => \&cmd_print,
 
         # special PBot command
-        'print_last_statement' => \&cmd_print,
+        'print_last_statement' => \&cmd_print_last_statement,
     );
 
     $command = unescape($command);
@@ -423,6 +423,22 @@ sub cmd_print($context, $args) {
     }
 }
 
+sub cmd_print_last_statement($context, $args) {
+    # invoke the last statement
+    my $console = gdb_send_and_read_console($context, "print $args");
+
+    # don't print last statement if there was program output
+    return if -s OUTPUT_FILENAME;
+
+    foreach my $output (@$console) {
+        last if $output->{_type} eq RESULT;
+
+        if ($output->{_text} =~ /^\$\d+\s*=\s*(.*)/) {
+            print_gdb_output($context, "no output: $args = $1");
+        }
+    }
+}
+
 sub handle_program_exit($context, $data) {
     my $reason = $data->{reason};
 
@@ -625,7 +641,7 @@ sub run_program($context) {
 
 sub main {
     # first command-line argument can override file to debug
-    my $prog = $ARGV[0] // './prog';
+    my $prog = shift @ARGV // './prog';
 
     # start gdb and grab references to its input and output streams
     open2(my $out, my $in, "LIBC_FATAL_STDERR=1 MALLOC_CHECK_=1 gdb -i mi3 -q -nx $prog");

applets/compiler_vm/guest/bin/setup-guest

@@ -1,6 +1,6 @@
 cp guest/bin/* /usr/local/bin
 
-mkdir /usr/local/share/pbot-vm/ > /dev/null
+mkdir -p /usr/local/share/pbot-vm/
 cp -r guest/lib/Languages/ /usr/local/share/pbot-vm/
 
 cp guest/include/prelude.h /usr/include
@@ -9,8 +9,11 @@ cp guest/polkit/* /etc/polkit-1/rules.d/
 
 nmcli networking off
 
+if ! grep -qF "pbot-vm" /root/.bashrc; then
+  echo '# pbot-vm' >> /root/.bashrc
   echo unset DEBUGINFOD_URLS >> /root/.bashrc
   echo export ASAN_OPTIONS=detect_leaks=0 >> /root/.bashrc
+fi
 
 echo PBot Guest VM is now set up.
 echo

applets/compiler_vm/guest/bin/start-guest

@@ -143,6 +143,8 @@ sub run_server {
                 system("rm -rf /home/$USERNAME/prog*");
                 system("pkill -u $USERNAME");
 
+                system("date -s \@$compile_in->{date}");
+
                 $ENV{USER} = $USERNAME;
                 $ENV{LOGNAME} = $USERNAME;
                 $ENV{HOME} = $home;
@@ -205,11 +207,11 @@ sub interpret {
 
     $mod->preprocess;
 
-    print "after preprocess: ", Dumper $mod, "\n";
+    #    print "after preprocess: ", Dumper $mod, "\n";
 
     $mod->postprocess if not $mod->{error} and not $mod->{done};
 
-    print "after postprocess: ", Dumper $mod, "\n";
+    # print "after postprocess: ", Dumper $mod, "\n";
 
     if (exists $mod->{no_output} or not length $mod->{output}) {
         if ($h{factoid}) {

applets/compiler_vm/guest/lib/Languages/_c_base.pm

@@ -20,8 +20,6 @@ sub preprocess {
   print $fh "$input\n";
   close $fh;
 
-  $self->execute(10, undef, 'date', '-s', "\@$self->{date}");
-
   my @cmd = $self->split_line($self->{cmdline}, strip_quotes => 1, preserve_escapes => 0);
 
   if ($self->{code} =~ m/print_last_statement\(.*\);$/m) {
@@ -78,15 +76,26 @@ sub postprocess {
   }
 
   print "Executing gdb\n";
-  my @args = $self->split_line($self->{arguments}, strip_quotes => 1, preserve_escapes => 0);
   my ($exitval, $stdout, $stderr);
 
+  my $ulimits = "ulimit -f 2000; ulimit -t 8; ulimit -u 200";
+
+  my @args = $self->split_line($self->{arguments}, strip_quotes => 1, preserve_escapes => 0);
+
+  my $quoted_args = '';
+
+  foreach my $arg (@args) {
+      $arg =~ s/'/'"'"'/g;
+      $quoted_args .= "'$arg' ";
+  }
+
   if ($self->{cmdline} =~ /-fsanitize=(?:[^ ]+,)?address/) {
       # leak sanitizer doesn't work under ptrace/gdb
       # ASAN_OPTIONS=strict_string_checks=1:detect_stack_use_after_return=1:check_initialization_order=1:strict_init_order=1
-      ($exitval, $stdout, $stderr) = $self->execute(60, undef, './prog', @args);
+      ($exitval, $stdout, $stderr) = $self->execute(60, "$ulimits; ./prog $quoted_args\n", '/bin/sh');
   } else {
-      ($exitval, $stdout, $stderr) = $self->execute(60, undef, 'guest-gdb', @args);
+      my $input = "$ulimits; guest-gdb ./prog $quoted_args";
+      ($exitval, $stdout, $stderr) = $self->execute(60, $input, '/bin/sh');
   }
 
   my $result = $stderr;

applets/compiler_vm/guest/lib/Languages/_default.pm

@@ -8,9 +8,6 @@ package _default;
 use warnings;
 use strict;
 
-use feature "switch";
-no if $] >= 5.018, warnings => "experimental::smartmatch";
-
 use IPC::Run qw/run timeout/;
 use Data::Dumper;
 
@@ -45,13 +42,21 @@ sub preprocess {
   print $fh $self->{code} . "\n";
   close $fh;
 
-  $self->execute(10, undef, 'date', '-s', "\@$self->{date}");
-
   print "Executing [$self->{cmdline}] with args [$self->{arguments}]\n";
-  my @cmdline = $self->split_line($self->{cmdline}, strip_quotes => 1, preserve_escapes => 0);
-  push @cmdline, $self->split_line($self->{arguments}, strip_quotes => 1, preserve_escapes => 0);
 
-  my ($retval, $stdout, $stderr) = $self->execute(60, $self->{input}, @cmdline);
+  my @args = $self->split_line($self->{arguments}, strip_quotes => 1, preserve_escapes => 0);
+
+  my $quoted_args = '';
+
+  foreach my $arg (@args) {
+      $arg =~ s/'/'"'"'/g;
+      $quoted_args .= "'$arg' ";
+  }
+
+  $self->{input} = "ulimit -f 2000; ulimit -t 8; ulimit -u 200; $self->{cmdline} $quoted_args";
+
+  my ($retval, $stdout, $stderr) = $self->execute(60, $self->{input}, '/bin/sh');
+
   $self->{output} = $stderr;
   $self->{output} .= ' ' if length $self->{output};
   $self->{output} .= $stdout;