split out spamcheck/spamc to its own module.

This should hopefully make it easier to try other anti-spam
systems (or none at all) in the future.

1 files changed, 94 insertions, 0 deletions

diff --git a/lib/PublicInbox/Spamcheck/Spamc.pm b/lib/PublicInbox/Spamcheck/Spamc.pm
new file mode 100644
index 00000000..312e52df
--- /dev/null
+++ b/lib/PublicInbox/Spamcheck/Spamc.pm
@@ -0,0 +1,94 @@
+# Copyright (C) 2016 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+package PublicInbox::Spamcheck::Spamc;
+use strict;
+use warnings;
+use PublicInbox::Spawn qw(popen_rd spawn);
+use IO::File;
+use Fcntl qw(:DEFAULT SEEK_SET);
+
+sub new {
+        my ($class) = @_;
+        bless {
+                checkcmd => [qw(spamc -E --headers)],
+                hamcmd => [qw(spamc -L ham)],
+                spamcmd => [qw(spamc -L spam)],
+        }, $class;
+}
+
+sub spamcheck {
+        my ($self, $msg, $out) = @_;
+
+        my $tmp;
+        my $fd = _msg_to_fd($self, $msg, \$tmp);
+        my $rdr = { 0 => $fd };
+        my ($fh, $pid) = popen_rd($self->{checkcmd}, undef, $rdr);
+        defined $pid or die "failed to popen_rd spamc: $!\n";
+        my $r;
+        unless (ref $out) {
+                my $buf = '';
+                $out = \$buf;
+        }
+        do {
+                $r = sysread($fh, $$out, 65536, length($$out));
+        } while (defined($r) && $r != 0);
+        defined $r or die "read failed: $!";
+        close $fh or die "close failed: $!";
+        waitpid($pid, 0);
+        ($? || $$out eq '') ? 0 : 1;
+}
+
+sub hamlearn {
+        my ($self, $msg, $rdr) = @_;
+        _learn($self, $msg, $rdr, 'hamcmd');
+}
+
+sub spamlearn {
+        my ($self, $msg, $rdr) = @_;
+        _learn($self, $msg, $rdr, 'spamcmd');
+}
+
+sub _learn {
+        my ($self, $msg, $rdr, $field) = @_;
+        $rdr ||= {};
+        $rdr->{1} ||= $self->_devnull;
+        $rdr->{2} ||= $self->_devnull;
+        my $tmp;
+        $rdr->{0} = _msg_to_fd($self, $msg, \$tmp);
+        my $pid = spawn($self->{$field}, undef, $rdr);
+        waitpid($pid, 0);
+        !$?;
+}
+
+sub _devnull {
+        my ($self) = @_;
+        my $fd = $self->{-devnullfd};
+        return $fd if defined $fd;
+        open my $fh, '+>', '/dev/null' or
+                                die "failed to open /dev/null: $!";
+        $self->{-devnull} = $fh;
+        $self->{-devnullfd} = fileno($fh);
+}
+
+sub _msg_to_fd {
+        my ($self, $msg, $tmpref) = @_;
+        my $tmpfh;
+        my $fd;
+        if (my $ref = ref($msg)) {
+
+                return $msg->fileno if $ref ne 'SCALAR' && $msg->can('fileno');
+
+                $tmpfh = IO::File->new_tmpfile;
+                $tmpfh->autoflush(1);
+                $msg = \($msg->as_string) if $ref ne 'SCALAR';
+                print $tmpfh $$msg or die "failed to print: $!";
+                sysseek($tmpfh, 0, SEEK_SET) or
+                        die "sysseek(fh) failed: $!";
+                $$tmpref = $tmpfh;
+
+                return fileno($tmpfh);
+        }
+        $msg;
+}
+
+1;