Add json2pcap to write pcap files from JSON input.

Required the ability to open output files and write to them in
different ways.  For example, using Net::Pcap's functions for those
purposes.

bin/json2pcap

@@ -0,0 +1,7 @@
+#!/usr/bin/perl
+use App::PipeFilter::JsonToPcap;
+exit App::PipeFilter::JsonToPcap->new_with_options()->run();
+
+__END__
+
+# vim: ts=2 sw=2 expandtab

lib/App/PipeFilter/Generic.pm

@@ -29,7 +29,7 @@ sub filter_file {
   while ($self->read_input($ifh, \$buffer)) {
     next unless my (@input) = $self->decode_input(\$buffer);
     next unless my (@output) = $self->transform(@input);
-    print $ofh $_ foreach $self->encode_output(@output);
+    $self->write_output($ofh, $self->encode_output(@output));
   }
 }
 

lib/App/PipeFilter/Generic/Json.pm

@@ -6,6 +6,7 @@ extends 'App::PipeFilter::Generic';
 
 with qw(
   App::PipeFilter::Role::Reader::Sysread
+  App::PipeFilter::Role::Writer::Print
   App::PipeFilter::Role::Input::Json
   App::PipeFilter::Role::Output::Json
 );

lib/App/PipeFilter/JsonToPcap.pm

@@ -0,0 +1,19 @@
+package App::PipeFilter::JsonToPcap;
+
+use Moose;
+extends 'App::PipeFilter::Generic';
+
+with (
+  "App::PipeFilter::Role::Reader::Sysread",
+  "App::PipeFilter::Role::Input::Json",
+  "App::PipeFilter::Role::Transform::None",
+	"App::PipeFilter::Role::Opener::PcapOutput",
+  "App::PipeFilter::Role::Output::Pcap",
+  "App::PipeFilter::Role::Writer::Pcap",
+);
+
+1;
+
+__END__
+
+# vim: ts=2 sw=2 expandtab

lib/App/PipeFilter/PcapToJson.pm

@@ -6,6 +6,7 @@ extends 'App::PipeFilter::Generic';
 with (
   "App::PipeFilter::Role::Opener::PcapInput",
   "App::PipeFilter::Role::Reader::Pcap",
+  "App::PipeFilter::Role::Writer::Print",
   "App::PipeFilter::Role::Input::ArrayBuffer",
   "App::PipeFilter::Role::Transform::None",
   "App::PipeFilter::Role::Output::Json",

lib/App/PipeFilter/Role/Opener/PcapOutput.pm

@@ -0,0 +1,27 @@
+package App::PipeFilter::Role::Opener::PcapOutput;
+
+use Moose::Role;
+
+use Net::Pcap qw(DLT_EN10MB pcap_open_dead pcap_dump_open);
+
+sub open_output {
+  my ($self, $filename) = @_;
+
+	my $pcap;
+	unless ($pcap = pcap_open_dead(DLT_EN10MB, 65536)) {
+		die "couldn't pcap_open_dead: $!";
+	}
+
+	my $dumper;
+	unless ($dumper = pcap_dump_open($pcap, $filename)) {
+		die "couldn't open $filename for writing: " . pcap_geterr($pcap);
+	}
+
+	return $dumper;
+}
+
+1;
+
+__END__
+
+# vim: ts=2 sw=2 expandtab

lib/App/PipeFilter/Role/Output/Pcap.pm

@@ -0,0 +1,31 @@
+package App::PipeFilter::Role::Output::Pcap;
+
+use Moose::Role;
+
+use Net::Pcap qw(pcap_dump);
+
+sub encode_output {
+  # Skips $self in $_[0].
+
+  return(
+    map {
+      my $pcap_rec = $_;
+      my $packet   = pack "H*", delete $pcap_rec->{pcap_data};
+
+      +[
+        {
+          map { /^pcap_(\S+)/ ? ($1 => $pcap_rec->{$_}) : () }
+          keys %$pcap_rec
+        },
+        $packet
+      ];
+    }
+    @_[2..$#_]
+  );
+}
+
+1;
+
+__END__
+
+# vim: ts=2 sw=2 expandtab

lib/App/PipeFilter/Role/Writer/Pcap.pm

@@ -0,0 +1,18 @@
+package App::PipeFilter::Role::Writer::Pcap;
+
+use Moose::Role;
+use Net::Pcap qw(pcap_dump pcap_dump_flush);
+
+sub write_output {
+	my $pcap_dumper = $_[1];
+
+  pcap_dump($pcap_dumper, @$_) foreach @_[2..$#_];
+  pcap_dump_flush($pcap_dumper);
+}
+
+no Moose::Role;
+1;
+
+__END__
+
+# vim: ts=2 sw=2 expandtab

lib/App/PipeFilter/Role/Writer/Print.pm

@@ -0,0 +1,13 @@
+package App::PipeFilter::Role::Writer::Print;
+
+use Moose::Role;
+
+sub write_output {
+  print { $_[1] } @_[2..$#_];
+}
+
+1;
+
+__END__
+
+# vim: ts=2 sw=2 expandtab