compiler_vm: added functionality to be executed without qemu, via cc script; added gdb debugging to watchdog

modules/compiler_vm/README

@@ -1,22 +1,49 @@
 Installation:
 
+If you want to run the compiler inside a virtual machine for more security,
+these scripts are designed to work with qemu 0.11.1.  This is required in
+order to use PBot's trigger.  
+
+In addition, you can use the provided 'cc' script to use your local compiler tools
+without installing qemu.  No PBot installation or configuration is required in this case.
+
+To use the local non-vm 'cc' script, you will need to have gcc, gdb and astyle installed locally.
+
+Be aware that you need to single-quote or escape the code if you use the local 'cc' within a shell,
+e.g.:  ./cc 'char s[] = "hello, world"; puts(s);  if(s[0] == \'h\') puts("true");' 
+
+WARNING: Using the local 'cc' script outside of the virtual machine will not use qemu at all; 
+         it will affect local system -- compile "safe" code!
+
+Virtual machine installation:
+
 You will need to download qemu and set up a virtual machine containing a system
 with a compiler and, optionally, sensible ulimits/fork-preventation/other security.
 
-Then you will need to edit some of the following files and replace IP addresses
+1) copy compiler_vm_server.pl and compiler_watchdog.pl to the virtual machine.
-and paths where appropriate (some locations may not yet be documented).
+2) then start up the compiler_vm_server.pl script inside the virtual machine
+3) then connect to qemu's monitor and issue the 'savevm 1' command to save the virtual state
+   (After compiles, this state will be loaded via 'loadvm 1' to reset everything within the machine 
+    for a clean and working environment for subsequent compiles.)
 
-Once the files have been configured and copied to the appropriate locations,
+Now the virtual machine state 1 is saved in a state where it is listening for incoming code.  You can 
-you will need to first start up the compiler_vm_server.pl script, and then 
+go ahead and quit qemu without shutting down the guest operating sytem.
-connect to qemu's monitor and issue the 'savevm 1' command to save the virtual 
+
-machine in this state.  Between compiles, this state will be loaded via 
+Starting the virtual machine for PBot:
-'loadvm 1' in order to reset everything within the machine for a clean and working
+
-environment for subsequent compiles.
+Now that the virtual machine is configured and saved, you may launch the local server to listen for
+code from PBot to send to the virtual machine's server.  To do so, run the compiler_server.pl script.
 
 Files:
 
 (Read within each file for configuration instructions.)
 
+- cc: Allows you to use the compiler locally with or without qemu installed.
+      Can be used within virtual machine for testing.
+      Must have gcc, gdb and astyle installed locally if not used within virtual machine.
+      WARNING: If not used within virtual machine will not use qemu at all and will 
+               affect local system -- compile "safe" code!
+
 - compiler_client.pl:  Main entry point for compiling snippets.  Sends over TCP to
                        compiler_server.pl.  This file can be run be run from the
                        client machine or anywhere.

modules/compiler_vm/compiler_vm_client.pl

@@ -9,6 +9,7 @@ use Text::Balanced qw(extract_codeblock extract_delimited);
 use IO::Socket;
 use LWP::UserAgent;
 
+my $USE_LOCAL        = defined $ENV{'CC_LOCAL'}; 
 my $MAX_UNDO_HISTORY = 100;
 
 my $output = "";
@@ -28,19 +29,6 @@ my %preludes = (
                  'C++'   => "#include <iostream>\n#include <cstdio>\n\nusing namespace std;\n\n",
                );
 
-sub reset_vm {
-  my $sock = IO::Socket::INET->new(PeerAddr => '127.0.0.1', PeerPort => '4445', Proto => 'tcp', Type => 'SOCK_STREAM');
-  die "Could not create socket: $!" unless $sock;
-
-  $sock->autoflush();
-  print $sock "loadvm 2\r\n";
-  while(my $line = <$sock>) {
-    last if $line =~ /loadvm 2/;
-  }
-  sleep 2;
-  $sock->shutdown(1);
-}
-
 sub pretty {
   my $code = join '', @_;
   my $result;
@@ -76,20 +64,28 @@ sub paste_codepad {
 }
 
 sub compile {
-  my ($lang, $code, $args, $input) = @_;
+  my ($lang, $code, $args, $input, $local) = @_;
 
-  my $sock = IO::Socket::INET->new(PeerAddr => '127.0.0.1', PeerPort => '4444', Proto => 'tcp', Type => 'SOCK_STREAM');
+  my ($compiler, $compiler_output, $pid);
  
-  die "Could not create socket: $!" unless $sock;
+  if(defined $local and $local != 0) {
+    print "Using local compiler instead of virtual machine\n";
+    $pid = open2($compiler_output, $compiler, './compiler_vm_server.pl') || die "repl failed: $@\n";
+    print "Started compiler, pid: $pid\n";
+  } else {
+    $compiler  = IO::Socket::INET->new(PeerAddr => '127.0.0.1', PeerPort => '4444', Proto => 'tcp', Type => 'SOCK_STREAM');
+    die "Could not create socket: $!" unless $compiler;
+    $compiler_output = $compiler;
+  }
 
-  print $sock "compile:$lang:$args:$input\n";
+  print $compiler "compile:$lang:$args:$input\n";
-  print $sock "$code\n";
+  print $compiler "$code\n";
-  print $sock "compile:end\n";
+  print $compiler "compile:end\n";
 
   my $result = "";
   my $got_result = 0;
 
-  while(my $line = <$sock>) {
+  while(my $line = <$compiler_output>) {
     $line =~ s/[\r\n]+$//;
 
     last if $line =~ /^result:end/;
@@ -106,7 +102,9 @@ sub compile {
     }
   }
 
-  close $sock;
+  close $compiler;
+  close $output if defined $output;
+  waitpid($pid, 0) if defined $pid;
   return $result;
 }
 
@@ -640,7 +638,7 @@ if(defined $got_run and $got_run eq "paste") {
 
 print FILE "$nick: [lang:$lang][args:$args][input:$input]\n$code\n";
 
-$output = compile($lang, $code, $args, $input);
+$output = compile($lang, pretty($code), $args, $input, $USE_LOCAL);
 
 $output =~ s/cc1: warnings being treated as errors//;
 $output =~ s/ Line \d+ ://g;
@@ -653,12 +651,16 @@ $output =~ s/\/tmp\/.*\.o://g;
 $output =~ s/collect2: ld returned \d+ exit status//g;
 $output =~ s/\(\.text\+[^)]+\)://g;
 $output =~ s/\[ In/[In/;
+$output =~ s/warning: Can't read pathname for load map: Input.output error.//g;
 
 my $left_quote = chr(226) . chr(128) . chr(152);
 my $right_quote = chr(226) . chr(128) . chr(153);
 $output =~ s/$left_quote/'/g;
 $output =~ s/$right_quote/'/g;
 
+$output =~ s/[\r\n]+/ /g;
+$output =~ s/\s+/ /g;
+
 $output = $nooutput if $output =~ m/^\s+$/;
 
 unless($got_run) {
@@ -668,5 +670,3 @@ unless($got_run) {
 }
 
 print "$nick: $output\n";
-
-#reset_vm;

modules/compiler_vm/compiler_vm_server.pl

@@ -3,27 +3,36 @@
 use warnings;
 use strict;
 
+my $USE_LOCAL = defined $ENV{'CC_LOCAL'}; 
+
 my %languages = (
   'C' => {
-    'cmdline' => 'gcc $args $file -o prog',
+    'cmdline' => 'gcc $args $file -o prog -ggdb',
     'args' => '-Wextra -Wall -Wno-unused -std=gnu89',
     'file' => 'prog.c',
   },
   'C++' => {
-    'cmdline' => 'g++ $args $file -o prog',
+    'cmdline' => 'g++ $args $file -o prog -ggdb',
     'args' => '',
     'file' => 'prog.cpp',
   },
   'C99' => {
-    'cmdline' => 'gcc $args $file -o prog',
+    'cmdline' => 'gcc $args $file -o prog -ggdb',
-    'args' => '-Wextra -Wall -Wno-unused -pedantic -std=c99',
+    'args' => '-Wextra -Wall -Wno-unused -pedantic -std=c99 -lm',
     'file' => 'prog.c',
   },
 );
 
 sub runserver {
-  open(my $input, '<', "/dev/ttyS0") or die $!;
+  my ($input, $output);
-  open(my $output, '>', "/dev/ttyS0") or die $!;
+
+  if(not defined $USE_LOCAL or $USE_LOCAL == 0) {
+    open($input, '<', "/dev/ttyS0") or die $!;
+    open($output, '>', "/dev/ttyS0") or die $!;
+  } else {
+    open($input, '<', "/dev/stdin") or die $!;
+    open($output, '>', "/dev/stdout") or die $!;
+  }
 
   my $lang;
   my $code;
@@ -49,8 +58,12 @@ sub runserver {
       print $output "result:$result\n";
       print $output "result:end\n";
 
+      if(not defined $USE_LOCAL or $USE_LOCAL == 0) {
         print "input: ";
         next;
+      } else {
+        exit;
+      }
     }
 
     if($line =~ m/^compile:\s*(.*)/) {
@@ -107,14 +120,18 @@ sub interpret {
 
   print "Executing [$cmdline]\n";
   my ($ret, $result) = execute(60, $cmdline);
-  print "Got result: ($ret) [$result]\n";
+  # print "Got result: ($ret) [$result]\n";
 
+  # if exit code was not 0, then there was a problem compiling, such as an error diagnostic
+  # so return the compiler output
   if($ret != 0) {
     return $result;
   }
 
   my $output = "";
 
+  # no errors compiling, but if $result contains something, it must be a warning message
+  # so prepend it to the output
   if(length $result) {
     $result =~ s/^\s+//;
     $result =~ s/\s+$//;
@@ -123,11 +140,11 @@ sub interpret {
 
   ($ret, $result) = execute(5, "./compiler_watchdog.pl");
 
-  print "Executed prog; got result: ($ret) [$result]\n";
-
   $result =~ s/^\s+//;
   $result =~ s/\s+$//;
 
+  # print "Executed prog; got result: ($ret) [$result]\n";
+
   if(not length $result) {
     $result = "Success (no output).\n" if $ret == 0;
     $result = "Success (exit code $ret).\n" if $ret != 0;

modules/compiler_vm/compiler_watchdog.pl

@@ -4,6 +4,7 @@ use warnings;
 use strict;
 
 use POSIX ":sys_wait_h";
+use IPC::Open2;
 
 my @signame;
 $signame[0] = 'SIGZERO';
@@ -76,6 +77,39 @@ $signame[66] = 'SIGCLD';
 $signame[67] = 'SIGPOLL';
 $signame[68] = 'SIGUNUSED';
 
+sub debug_program {
+  my ($input, $output);
+
+  my $pid = open2($output, $input, 'gdb -silent -batch -x debugcommands ./prog ./core 2>/dev/null');
+
+  if(not $pid) {
+    print "Error debugging program.\n";
+    exit;
+  }
+
+  my $result = "";
+
+  while(my $line = <$output>) {
+	  if($line =~ s/^#\d+//) {
+		  $line =~ s/\s*0x[0-9a-fA-F]+\s*//;
+		  $result .= "$line ";
+	  }
+	  elsif($line =~ s/^\d+//) {
+		  $result .= "statement: $line";
+		  last;
+	  }
+  }
+
+  close $output;
+  close $input;
+  waitpid($pid, 0);
+
+  $result =~ s/^\s+//;
+  $result =~ s/\s+$//;
+  print "$result\n";
+  exit;
+}
+
 sub reaper {
   my $child;
   while (($child=waitpid(-1,WNOHANG))>0) {
@@ -92,6 +126,7 @@ sub reaper {
 
     if($wifsignaled == 1) {
       print "\nProgram received signal $wtermsig ($signame[$wtermsig])\n";
+      debug_program if $wtermsig != 0;
       exit;
     }